mie.uc.edu

MARC VII ABSTRACTS 1 102 A DETAILED STUDY OF THE GAMMA RADIOLYSIS OF HEDTA IN A SIMULATED, MIXED WASTE. A. P. Toste and T. Pilot. Department of Chemistry, Missouri State University, Springfield, MO 65804, USA.. This report addresses a detailed study of the gamma radiolysis of the parent compound N-(2-hydroxyethyl)ethylenediaminetriacetic Acid (HEDTA) in a simulant of a Hanford mixed waste, which was irradiated in a 60Co-source at gammadoses of 0 - 7.5 x 106 ± 10% R. HEDTA degradation was both rapid and extensive; only 5.6% remained by the end of the study. HEDTA radiolysis yielded four degradation products: glyoxylic acid, N-(Nitroso)iminodiacetic Acid (NIDA) and 2 dicarboxylic acids, ethandioic (oxalic) and propandioic (malonic) acids. The degradation products formed at different rates. Glyoxylic acid genesis dominates, followed by NIDA, and eventually the dicarboylic acids. Formation of the nitrosated species, NIDA, presumably via nitrosation of iminodiacetic acid (IDA), increases with time. Comparison with previous degradation studies on simulated mixed wastes containing other parent chelating and complexing agents, added singly and as mixtures, suggests that HEDTA is exceptionally labile. 103 ADVANCES IN RAPID RADIOCHEMISTRY METHODS IN RESPONSE TO EMERGENCY RESPONSE NEEDS - AN UPDATE ON ASTM METHODS DEVELOPMENT Doug Van Cleef (ORTEC), ASTM D19.04 Rapid Methods Task Group. Events of recent years have made the emergency response community significantly more aware of the need for rapid assessment of the presence and type of chemical, biological, or nuclear materials. Since 2003, numerous volunteer members of ASTM Committee D19.04, representing numerous national laboratories, government agencies, and the private sector have collaborated on the development and testing of such methods for radiochemical analysis in response to inquiries by various emergency response organizations. This presentation provides an update on works in progress within the Rapid Methods Task Group of this ASTM Committee. Measurement of Ultra-trace level Molybdenum in Silicon Wafers Utilizing Neutron Activation Analysis Craig Swanson and Albert Filo, Eastman Kodak Co, 1999 Lake Ave, Rochester, NY 14420, USA. For many years, Eastman Kodak‘s Image Sensor Solutions Division and Neutron Activation Analysis Laboratory have participated in a collaborative analytical project to identify and quantify ultra-trace level metallic impurities in silicon wafers. NAA detection limits (atoms cm-3) for these analyses range from 1E7 for Au to 3E12 for Fe. The detection limit (atoms cm-3) for Mo is 5E10. This experiment involved the analyses of a series of Si wafers that were implanted with varying amounts of Mo-98. The objectives were to verify the accuracy and precision of our analytical procedure and experimentally resolve some discrepancies about 104 2 the relative intensities of the two primary gamma-rays (140.5 and 739.4 KeV) of Mo-99 that appear in some gamma-ray databases. This poster will present a general overview of our analytical method as well as the data obtained from the analyses of the Mo-implanted wafers. 105 JOINT ASSESSMENT OF RESPONSES OF BIOMONITORS TO AIRBORNE NICKEL AND VANADIUM THROUGH NUCLEAR AND NON-NUCLEAR TECHNIQUES A.M.G. Pacheco1, M.C. Freitas2, S. Sarmento2, M.S. Baptista3, M.T. Vasconcelos3,4, J.P. Cabral3,5 -- 1CVRM-IST (Technical University of Lisbon), Av. Rovisco Pais 1, 1049-001 Lisboa, Portugal; 2Reactor-ITN (Technological and Nuclear Institute), E.N. 10, 2686-953 Sacavém, Portugal; 3CIIMAR (University of Porto), Rua dos Bragas 289, 4050-123 Porto, Portugal; 4Chemistry Department – Faculty of Sciences (University of Porto), Rua do Campo Alegre 687, 4169-071 Porto, Portugal; 5Botany Department – Faculty of Sciences (University of Porto), Rua do Campo Alegre 1191, 4150-181 Porto, Portugal. In an utilitarian sense, biomonitoring refers to any intentional use of an existing species -- animal or plant, lower or higher -- for an intensive assessment of a certain attribute -usually, an environmental one -- with a significant reduction in total sampling costs, when comparing to an operation with physical-chemical devices. Tracking distinctive, measurable changes in organisms may result in relevant information at virtually any space-time scale, from characteristics of the biosphere at large to specific aspects at the habitat level. This is the comprehensive scope though: when it comes to botanical specimens in terrestrial environments, one invariably thinks of biomonitoring airborne contaminants at ground level. The present study deals with the influence of atmospheric conditions (precipitation regimes) on biological uptake, by looking into the concentrations of nickel and vanadium in lichen thalli and tree bark after continuous and discontinuous field trials at littoral locations impacted by anthropogenic emissions. Biological monitors were assessed by k0-INAA and AAS, and total-deposition samples by ICP-MS. The results indicate that the V/Ni ratio has gone through significant changes, even if the starting material (prior to exposure) could be found to average in a typical 0.5 proportion, and that such changes appear related to rainfall-drought cycles. Vanadium uptake by both lichens and bark seems easier than nickel's, with an effective rate of accumulation that likely benefits also from an alternation of wet-dry periods. RADIOCHEMISTRY AS A TOOL IN RIB STUDIES W. Loveland, Oregon State University. Studies of nuclear reactions induced by radioactive ion beams (RIBs) are frequently characterized by low event rates due to the low beam intensities used. Radiochemistry and radioanalytical techniques can be of advantage in these studies. We discuss three applications from our current research: (a) in-beam alpha spectroscopy of short-lived reaction products in the Pb/Bi region (b) radiochemical 107 3 separation and identification of 230U produced in the ―inverse fission‖ of U, i.e., the 100Mo + 132Sn reaction and (c) the isolation and characterization of Ge and As evaporation residues from fission studies with 9,11Li (at beam intensities as low as 600 pps). 108 CHARACTERIZATION OF A PLUTONIUM BERYLLIUM SOURCE FOR USE IN NEUTRON DAMAGE STUDIES M. A. Griffin*1, S.Landsberger1, M. E. Cournoyer2. 1Mechanical Engineering Department, The University of Texas at Austin, Austin, TX, 2Los Alamos National Laboratory, Los Alamos, NM. Standard lead loaded Hypalon gloves deteriorate at an accelerated pace in the glovebox environments of Los Alamos National Laboratory. In an effort to minimize glovebox breaches, a project was undertaken to characterize polymer damage due to various environments. For one such study, experimental techniques were used to facilitate the use of a neutron source in damage studies involving glovebox gloves. In order to identify the radiation field experienced by the polymer samples, a characterization of the neutron source in the experimental setup was needed. The Plutonium-Beryllium source used was chosen to mimic an average neutron flux in a typical LANL glovebox. However, it was surmised that a more exact experimental flux should be found rather then using merely numerical analysis. In order to fully characterize the field, an experiment was specifically designed to determine the neutron flux in a fixed geometry by use of both bare gold foils and cadmium lined foils. Two competing glovebox glove materials, namely Hypalon/Pb/Hypalon and Polyurethane/Pb/Hypalon, were studied. Polyurethane shows superior properties when compared against the standard Hypalon/Pb/Hypalon glove; however Polyurethane is shown to degrade faster following neutron irradiation. BULK AND TRACE ELEMENT CONTENTS IN SPICES FROM SRI LANKA DETERMINED BY ICPMS, NUCLEAR AND NUCLEARRELATED TECHNIQUES 1Chery, 1Van Lierde, 1Vanhaecke, 2Jayasekera, 3Freitas 1 Laboratory of Analytical Chemistry, Ghent University, Institute for Nuclear Sciences, Preoftuinstraat 86, B-9000 Ghent, Belgium, Frank.Vanhaecke@UGent.be, 2 Department of Botany, University of Kelaniya, Sri Lanka, ranjith@kln.ac.lk, 3 ITN (Technological and Nuclear Institute), Reactor, E.N. 10, 2686-953 Sacavém, Portugal, cfreitas@itn.pt. Elemental composition spices may be influenced by inherent plants characteristics, environmental conditions, agronomic practices and handling & processing methods of plants/plant parts during and after harvest. A preliminary study showed that some spices used in Sri Lanka were enriched in certain trace elements, probably due to contamination from various sources. A systematic study to monitor levels of bulk and trace elements in spices, curry, chilli and turmeric powders consumed in Sri Lanka was accomplished. Determination of concentration was simplified by using reliable, simultaneous multi-element techniques. 109 4 Results on ICP/MS, INAA, EDXRF were validated by analysing NIST1572 and NIST1573. Quantitative results were obtained for Bi, Co, Cu, Mo, Ni, Pd, REEs, Sb, Se, Sn, Sr, Te, Th, Tl using sector field ICP/MS, operated at low and medium mass resolution. Comparison of INAA and EDXRF resulted in the following: (1) in the curry powder, Mg value obtained by INAA was somewhat overestimated; fairly good agreement was found in turmeric powder (2) for Mn systematically higher values were obtained by EDXRF for all samples analysed; an opposite trend occurred for Sr (3) in turmeric powder Zn determined by INAA slightly exceeded the EDXRF value, while in the curry powder an opposite trend was observed. 110 TRACE-ELEMENT CONTENTS IN RAW FOOD ITEMS CONSUMED IN MAINLAND PORTUGAL, DETERMINED BY k0INAA Freitas 1, Ventura 1, Bacchi 2, Dionísio 1, Pacheco 3. 1 ITN (Technological and Nuclear Institute), Reactor, E.N. 10, 2686-953 Sacavém, Portugal, cfreitas@itn.pt, 2 S. Paulo University, Nuclear Energy Center for Agriculture, University of São Paulo, CENA/USP, Avenida Centenário 303, 13416-000 Piracicaba SP, Brasil, mabacchi@cena.usp.br, 3 CVRM-IST, Technical University of Lisbon, Av. Rovisco Pais 1, 1049-001 Lisboa, Portugal, apacheco@ist.utl.pt. In March 2003, food items of Portuguese origin were purchased from a large commercial area in Coimbra. The selected items were: chicken, pork and cow meat, eggs, two sorts of rice, and two sorts of bean. They were frozen raw and freeze-dried raw (using a HetoDW8); average weight loss was around 70% for meat and eggs, and between 5% and 9% for rice and bean grains. Samples were then milled (Teflon™ balls and capsules), and stored at -20ºC until put through k0-standardised instrumental neutron activation analysis (INAA) for determination of minor and trace elements. Quality control was assessed through analysis of NIST Bovine liver, NIST Rice flour and IAEA Animal muscle. Compton suppressed for medium and long-lived nuclides and normal gamma-ray spectra for short, medium and long-lived were acquired at Nuclear Energy Center for Agiculture and ITN, respectively. At ITN, epithermal NAA was also applied. Advantages of 1) Compton suppression application to INAA and 2) use of epithermal neutron irradiations are demonstrated. Concentrations of the determined chemical elements are discussed in terms of the available European-Union legislation, and with chemical element contents in the studied food items reported in the literature. COHN ANALYSIS: BODY COMPOSITION MEASUREMENTS BASED ON THE ASSOCIATED PARTICLE IMAGING AND PROMPT-GAMMA NEUTRON ACTIVATION ANALYSIS TECHNIQUES Kenneth J. Ellis, Roman J. Shypailo, USDA/ARS Children's Nutrition Research Center, Dept. Pediatrics, Baylor College of Medicine, 1100 Bates St., Houston, TX 77030. The measurement of carbon (C), oxygen (O), 111 5 hydrogen (H), and nitrogen (N) in the human body can be used to calculate the relative contents of body fat, protein, and water. A system based on prompt-gamma neutron activation analysis (PGNAA), coupled with the associated particle imaging (API) technique, is being developed for this purpose. A compact D,T neutron generator (>1 x 107 n/sec output) with an internal alpha particle detector is used. The counting system consists of 6 shielded bismuth germanate (BGO) detectors (10 cm x 10 cm x 10 cm) operated with fast-timing electronics to detect only gamma-rays within a 150 nanosec time window following a trigger pulse generated by the alpha detector. The body is scanned from the shoulder to the knee in about 20 minutes, with the whole-body dose equivalent less than 0.4 mSv. The cumulative gamma-ray spectra in the 2 MeV to 11.5 MeV region is collected and analyzed for multiple peaks attributed to body C,O,H, and N. Precision for each element, based on tissue-equivalent phantoms, are in the 2-4% range, which are sufficient for population studies in adults. Further improvements are needed to extend the measurements to pediatric clinical research studies. 112 COMPTON SUPPRESSION SPECTROMETRY FOR ANALYSIS OF SHORT-LIVED NEUTRON ACTIVATION PRODUCTS IN FOODS David L. Anderson and William C. Cunningham, Elemental Research Branch (HFS-338), U. S. Food and Drug Administration, 5100 Paint Branch Parkway, College Park, MD (USA) 20740-3835. Compton suppression (anticoincidence) spectrometry was used to analyze foods for 16 elements with short-lived neutron activation products (half-lives of about 2 minutes to 1.5 days). Irradiation and gamma-ray counting conditions were optimized for iodine detection to provide quality assurance analyses for FDA's Total Diet Study (TDS). Iodine mass fractions (0.075 to 2.03 mg/kg) were measured in 19 of 42 foods analyzed. 3σ limits of detection (LODs) ranged from 0.03 to 1.4 mg iodine/kg for foods containing 70 mg/kg to 3.6% sodium chloride, representing improvements (compared to singles spectrometry) of about 30 to 35%. For Al, As, Ba, Br, Ca, Cl, Cu, K, Mg, Mn, Na, Sr, Ti, V, and Zn, LODs were lowered (up to a factor of 2) to 0.6, 0.3, 0.7, 0.06, 1, 0.6, 0.2, 10, 2, 0.004, 0.7, 1, 0.8, 0.009, and 20 mg/kg, respectively. Background suppression factors of about 2 to 8 were achieved over the energy range 400 to 3200 keV. Anticoincidence spectrometry reduced photopeak areas for lines at 847 keV (from Mn-56) and 620 and 554 keV (from Br-82), which generally improve peak-fitting capabilities for Mg (844 keV). Br-80 (616 keV), and As (559 keV) lines. PROMPT-GAMMA NEUTRON ACTIVATION ANALYSIS SYSTEM DESIGN: EFFECTS OF D-T VERSUS D-D NEUTRON GENERATOR SOURCE SELECTION. Roman J. Shypailo and Kenneth J. Ellis USDA/ARS Children's Nutrition Research Center Dept. of Pediatrics, Baylor College of Medicine, Houston, TX 77030 USA. 113 6 Prompt-gamma neutron activation analysis (PGNAA) is used for the noninvasive measurement of human body composition. Advancements in portable, compact neutron generator design have made those devices attractive as neutron sources. Two distinct neutron generators are available: D-D with 2.5 MeV neutrons and D-T with 14.2 MeV neutrons. To compare the performance of these two generators in our present PGNAA system, we performed Monte Carlo simulations (MCNP-4B2; Los Alamos National Laboratory) evaluating the nitrogen reactions produced in tissue-equivalent phantoms and the effects of background interference on the gamma detectors. Experimental measurements using phantoms were obtained as verification of the Monte Carlo predictions for counting precision and measurement sensitivity. Monte Carlo response curves showed increased gamma production per unit dose when using the lower energy D-D generator, suggesting that it is the more suitable choice for smaller sized subjects. However, non-uniform signal production within the irradiated body region may necessitate shielding and/or collimator design changes. The increased penetration by higher energy neutrons produced by the D-T generator supports its utility when examining larger, especially obese, subjects. A clinical PGNAA design incorporating both neutron generator options may be the best choice for a system required to measure a wide range of subject phenotypes. 114 OPTICALLY STIMULATED LUMINESCENCE RESPONSE OF COMMERCIAL SiO2 OPTICAL FIBER Espinosa, G.a and Bogard, J.S.b a) Instituto de Física, UNAM. Apartado Postal 20-364, 01000, México, D.F. b) Oak Ridge National Laboratory, PO Box 2008, Oak Ridge, TN 37831-6480, USA. espinosa@fisica.unam.mx. The use of Optically Stimulated Luminescence (OSL) for radiation dosimetry has become increasingly popular in recent years. The OSL method is based on luminescence emitted from semiconductor materials stimulated with specific wavelengths of light, after being exposed to ionizing radiation. The OSL intensity is a function of the radiation dose absorbed by the material. This work complements previous studies by the authors of the thermoluminescence (TL) response by SiO2 commercial optical fiber exposed to ionizing radiation and provides preliminary results describing some of the material‘s OSL properties. Linear OSL response to beta radiation dose, along with a consistent shape of the photon emission curve with time, were observed using a green/blue OSL excitation laser. The reproducibility of OSL response after repeated irradiations and the change in intensity with time were also examined. The search and characterization of materials that exhibit this OSL response, in parallel with the continued development of OSL methodology and instrumentation, is an important scientific and commercial issue. Acknowledgements. The authors wish to thank to J.I. Golzarri for his technical help. Also thanks to Metronet, S.A. de C.V., for providing the optical fiber material. This work was partially supported by Oak Ridge National Laboratory, managed by UT-Battelle 7 Corp. for the U.S. Department of Energy under contract number DE-AC0500-OR2-2725. One of the authors (GE) wishes to thank DGAPA-UNAM for economic support. 115 RADON AND PROGENY ALPHA-PARTICLE ENERGY ANALYSIS USING NUCLEAR TRACK METHODOLOGY Espinosa, G.a, Golzarri, J.I.a and Bogard, J.S.b a) Instituto de Física, UNAM. Apartado Postal 20-364, 01000, México, D.F. b) Oak Ridge National Laboratory, PO Box 2008, Oak Ridge, TN 37831-6480, USA. espinosa@fisica.unam.mx. A procedure for alpha energy analysis of radon and progeny using Nuclear Track Methodology (NTM) is described in this paper. The method is based on the relationship between alpha-particle energies deposited in polycarbonate material (CR-39) and the track size developed after a well-established chemical etching process. Track geometry, defined by parameters such as major or minor diameters, track area and overall track length, is shown to correlate with alpha-particle energy over the range 5.49 MeV (222Rn) to 7.69 MeV (214Po). Track features are measured and the data analyzed automatically using a digital imaging system and commercial PC software. Examination of particle track diameters in CR39 exposed to environmental radon reveals a multi-modal distribution. Locations of the maxima in this distribution are highly correlated with alpha particle energies of radon daughters, and the distributions are sufficiently resolved to identify the radioisotopes. This method can be useful for estimating the radiation dose from indoor exposure to radon and its progeny. This work was partially supported by Oak Ridge National Laboratory, managed by UT-Battelle Corp. for the U.S. Department of Energy under contract number DE-AC05-00-OR2-2725. One of the authors (GE) wishes to thank DGAPA-UNAM for economic support. PURIFICATION AND SEPARATION OF 239/240Pu AND 241Am IN BIOLOGICAL SAMPLES BY ANION EXCHANGE AND EXTRACTION CHROMATOGRAPHY FOR HIGH RESOLUTION ALPHA SPECTROMETRY ANALYSES S. Ridone, D. Arginelli,G. Berton, S. Bortoluzzi, G. Canuto, M. Montalto, M. Nocente, M. Vegro Italian National Agency for New Technologies, Energy and Environment-ENEA, Research Centre of Saluggia, Institute of Radiation Protection ION-IRP. The radiation protection physical surveillance program of some workers, involved in the decommissioning activities of a reprocessing nuclear plant, in the Research Centre of Saluggia of the Italian National Agency for New Technologies, Energy and Environment-ENEA, provides for radiotoxicological analyses on biological samples (urines and faeces), to detect possible internal contamination levels of transuranic elements (239/240Pu 241Am). All the samples of urines and faeces, collected in the monitoring period, were mineralised and plutonium was separated and purified through anion exchange chromatographic technique by means of AG 1-X2 resin chloride, and then electroplated. Its 117 8 activity was measured by high resolution alpha spectrometry.Although chemical yield and peak resolution were good, we wanted to improve our results and to find a method suitable for the simultaneous purification and separation of 241Am and 239/240Pu. In this work natural uranium could be a serious problem, especially for plutonium analyses, because if not separated natural uranium could reduce the peak resolution. The contemporary analysis of americium and plutonium is clearly complicated, time consuming and susceptible of human errors, but in our work we tried to find a way to standardize the method, making it easier and suitable for routine analyses, and reducing possible errors, too. 119 RADIOCHEMICAL ANALYSES OF RADIOLOGICALLYCONTAMINATED SOIL SAMPLES IN SUPPORT OF TRANSPORT MODELLING David J. Sims, William S. Andrews*, Xiaomei Wang and Katherine A.M. Creber, Department of Chemistry and Chemical Engineering, Royal Military College of Canada, Kingston, Ontario, K7K 7B4, CANADA *corresponding author E-mail: andrews-w@rmc.ca . In 1951, an experiment was conducted on the Alberta prairie to examine the weathering of fission products (simulated fallout from nuclear weapons releases). During the field trials, some 6.7 L of fission product and actinide solution leaked into the soil from a buried storage tank. In 2001, a project was initiated to determine the extent of the current soil contamination. This paper reports on analytical techniques used to analyze soil samples extracted from the contaminated site and the results of the analyses. Four analytical techniques have been used: gamma spectroscopy (GS), neutron activation analysis (NAA), liquid scintillation counting (LSC) and inductively coupled plasma- mass spectroscopy (ICP-MS). The main surviving radionuclides of interest were 137Cs, 90Sr, 238U, and 239Pu. GS and NAA proved quite useful in detecting and quantifying the gamma ray emitting radionuclides with little sample preparation. The beta-emitting 90Sr, however, had to be removed from the soil matrix by dissolving it in acid, followed by using resin extraction columns prior to introduction into the LSC. ICP-MS analysis was used to provide a comparison to the nuclear methods. ICP-MS provided better precision than NAA. 120 DIFFUSION COEFFICIENTS FOR ACTINIDES AND FISSION PRODUCTS IN UNSATURATED PRAIRIE SOIL David J. Sims, William S. Andrews* and Katherine A.M. Creber, Department of Chemistry and Chemical Engineering, Royal Military College of Canada, Kingston, Ontario, K7K 7B4, CANADA *corresponding author E-mail: andrews-w@rmc.ca . In 1951, a release of 6.7 L of an aqueous solution of irradiated uranium (360 GBq) occurred from an underground storage tank. A replication of the 9 dispersion of the actinides and fission products was conducted in the laboratory using neutron-irradiated and non-irradiated natural uranium and metal standards dissolved in acidic aqueous solutions that were added to columns containing uncontaminated prairie soil and then were allowed 12 to 14 months for contaminant transport. Soil samples were analyzed using gamma-ray spectroscopy, neutron activation analysis and liquid scintillation counting to determine the elemental concentrations of U, Cs and Sr. Diffusion coefficients from the 50 year soil samples and the lab soil samples were determined. The measured diffusion coefficients from the field samples were 3.0E-04 cm2 s-1 (Cs-137), 1.8E-09 cm2 s-1 (U-238) and 2.6E09 cm2 s-1 (Sr-90) and the values determined from lab simulation were 5E06 cm2 s-1 (Cs-137), 3E-05 cm2 s-1 (U-238) and 1.9E-05 cm2 s-1 (Sr-90). The differences between field and laboratory values may be due, in part, to differing soil densities (porosities) and environmental effects such as temperature and moisture, as well as uncertainties in the field measurements. Based on finite element modeling, 250 years after the 1951 contamination release, the soil concentration of the three noted contaminants will be less than their respective soil clearance level values and therefore will not pose a long term environmental hazard. 121 AUTOMATIC NAA - SATURATION ACTIVITIES G. P. Westphal and F. Grass Atominstitut der Oesterreichischen Universitaeten, Stadionallee 2, A-1020 Vienna, Austria. Reported on at the last Kona Conference, a system for Rapid Automatic NAA is based on a list of specific saturation activities determined for one irradiation position and one detector geometry. Combined with line energies and half-lives, this list serves for nuclide identification as well as for the calculation of elemental concentrations. Originally compiled from measurements of numerous standard reference materials, the list is being extended also by the calculation of saturation activities from k0 and Q0 factors, taking into account f and values of our irradiation position, and two -small and large - sample geometries. A systematic improvement of the SRM approach is currently being performed by pseudo-cyclic activation analysis, in an attempt to reduce counting errors. From these measurements, the list of saturation activities will be recalculated in an automatic procedure which could become part of our system's quality assurance. Last but not least a synthetic standard is being designed with special emphasis on short-lived isomeric transitions. To demonstrate the results of these endeavours a number of SRM's, mainly from the IAEA, are re-measured and discussed critically. Washington State University Nuclear Radiation Center E. Corwin, K. Fox. Nuclear Radiation Center, Washington State University. Completed in 1961, the Washington Sate University Nuclear Radiation Center (WSUNRC) is the home of a 1 Megawatt General Atomics TRIGA nuclear reactor, a 1000 Curie Cobalt-60 Irradiation Facility, and a Borated Neutron Capture Treatment Facility (BNCT). The Nuclear Radiation Center 122 10 is a facility unique to Washington State University, and is the only research reactor in Washington State. 123 USING SYNTHETIC MULTI-ELEMENT STANDARDS (SMELS) FOR THE CALIBRATION AND THE QUALITY CONTROL OF IRRADIATION FACILITIES IN THE BR1 REACTOR P. Vermaercke1, P. Robouch², L. Sneyers1, F. De Corte3. 1 SCK-CEN, Belgian Nuclear Research Centre, Boeretang 200, B-2400 Mol, Belgium ² IRMM, Institute for Reference Materials and Measurements, European Commission, Retieseweg, B-2440 Geel, Belgium. 3 Laboratory of Analytical Chemistry, Institute for Nuclear Sciences, Ghent University, Proeftuinstraat 86, B-9000 Gent, Belgium. The thermal to epithermal neutron flux ratio (f) and the deviation of the epithermal neutron spectrum from the 1/E shape (α) are essential parameters for the correct application of k0-standardised neutron activation analyses. Several methods are applied for the determination of f and α. They are based on Cd-ratio or Cd-covered multi-monitor methods or on bare-irradiations methods. The recently developed and characterized synthetic multi-element standard (SMELS) was designed as a validation tool of the proper implementation of the k0-NAA method in a laboratory. In particular, SMELS Type III contains Au and Zr, thus also allowing the direct determination of f and α. It could also be used as a quality control material to monitor the irradiation facility and the detector, thus replacing the traditional flux monitors. This paper presents the accuracy of the f and α determination in channels Y4 and S84 of the BR1 reactor. The effective use of the SMELS material is further discussed and demonstrated. DETERMINATION OF LOW LEVEL SULFUR IN STEELS BY RADIOCHEMICAL NEUTRON ACTIVATION ANALYSIS WITH LIQUID SCINTILLATION COUNTING Rick L. Paul, National Institute of Standards and Technology, Gaithersburg, MD 20899. A method has been developed for determination of low level sulfur in steels by radiochemical neutron activation analysis. The method makes use of 35S produced from 34S upon neutron irradiation. The sample is irradiated, mixed with sulfate carrier and dissolved in nitric and hydrochloric acids. The solution is evaporated to dryness, and nitrates destroyed by HCl evaporations. Sulfur is reduced to H2S by reaction with a mixture of HCl/HI/H3PO2, and the H2S collected in a dilute solution of NaOH. 3 mL of this solution are mixed with scintillation cocktail for measurement of 35S by liquid scintillation counting. The remainder of the solution is used for determination of carrier yield via iodometric titration. A detection limit of ~ 0.1 mg/kg has been determined. Measurement of sulfur in SRM 365 (Electrolytic Iron, certified sulfur mass fraction = 55 ± 2 mg/kg) gave a mass fraction of 58 ± 2 mg/kg (uncertainty = 2s based on measurement replication). A sulfur mass fraction of 8.4 ± 0.3 mg/kg (uncertainty = 2s based on measurement replication) has also been measured 124 11 in samples of ultra-high-purity iron. 126 INVESTIGATION OF THE DESTRUCTION OF CHEMICAL WARFARE AGENTS USING IONIZING RADIATION William S, Andrews, Edward A. Ough, Dragic Vukomanovic and Katherine A.M. Creber, Chemistry and Chemical Engineering, Royal Military College of Canada, Kingston ON CANADA K7K 7B4. For most of the twentieth century, research has been conducted into the use and dispersal of chemical warfare agents (CWA), such as bis-(2-chloroethyl)sulfide (also known as distilled mustard, mustard gas and HD). Recently, efforts have been undertaken to dispose of bulk agent and to remediate areas contaminated by research activities. Incineration is a standard industry approach to the disposal of hazardous waste, but public concerns about emissions often preclude its use. An alternative method for the destruction of CWA may be the application of ionizing radiation. There is little information in open literature about the effects of radiation on CWA; therefore, we have initiated a study to investigate the stability of mustard agent to various types of radiation. Samples of neat mustard and mustard mixed into soil analogues were inserted into core sites within the 20 kW reactor at the Royal Military College of Canada‘s Slowpoke-2 Facility and suspended against the reactor pool wall for periods from 30 min to 18 h at a thermal flux of 5×1010 neutrons/cm2s in-reactor and 1 to 3 weeks in the reactor pool. The results from GC-MS analysis are being used to qualify and quantify the decomposition products. INVESTIGATION OF A LOW-LEVEL RADIOACTIVE WASTE BURIAL SITE William S, Andrews, Elizabeth Inrig and Katherine A.M. Creber, Chemistry and Chemical Engineering, Royal Military College of Canada, Kingston ON CANADA K7K 7B4. From 1967 to 1971, low-level radioactive waste was collected from locations across Canada and shipped to a remote prairie location for burial. Although the general location of the burial sites was known, their precise locations had been lost over time. A further complication was that much more trench space had been prepared than had been used, so the actual locations of the radiological waste were also not known. The waste trench locations were determined from historical records, aerial photographs, and geophysical surveys. A site investigation was carried out in March, 2005 to confirm the trench locations and to sample the waste deposited therein. A number of test pits were systematically excavated and samples of waste and soil were collected. The site was found to contain both solid and liquid waste from agricultural, laboratory and military sources. Radioisotopes were present in items such as military compasses and dials, as well as waste from ground radar installations, such as electron tubes, klystrons, and waveguides. Samples were analyzed using a variety of techniques, including gamma-ray spectroscopy, gas chromatography/mass spectrometry, and liquid scintillation counting. This paper presents a 127 12 summary of the site investigation and the analyses performed. 128 Ultrasensitive AMS and its relation to radionuclides in the environment Gunther Korschinek, Fachbereich Physik E15, Technische Universität München. AMS is an ultrasensitive method for detection and measurement of very long-lived radionnuclides. During the last years we have optimized our AMS system in Munich further. Depending on the isotopes of interest isotopic ratios down to 10*-16 can be determined now. In the course of our studies 26Al and 53Mn measurements in environmental samples have been performed. The results will be shown and discussed. A new approach for the measurements of nuclides heavier than 100amu have been undertaken. Until now this mass range was only accessibly by selected isotopes like 129I or actinides. The achievements are promissing and exhibit the wide potentialities for AMS. The method will be shown and outlined in details. COMPARISON OF PORTABLE DETECTORS FOR URANIUM ENRICHMENT AND HOLDUP MEASURMENTS Duc T. Vo, Los Alamos National Laboratory, Group N-1, MS E-540, Los Alamos, NM 87545, USA. Uranium enrichment and holdup measurements require a detector capable of accurately obtaining the 186-keV peak area. The NaI detectors have been widely used for these tasks. However, for recycle uranium, the interference of the 239-keV gamma rays from the 232U decay chain would challenge the capabilities of the NaI detectors to accurately extract the area of the 186-keV peak. Using the CZT detectors, which have much better resolution than the NaI detectors, temporarily solved this interference problem. However, the CZT detectors have a set back that they are generally small and have low efficiencies, which would then require long acquisition time for reasonable statistics. Recently, two new types of scintillator detectors have been available commercially, LaCl3(Ce) and LaBr3(Ce). The cerium-doped lanthanum halide detectors, with comparable resolution but better efficiency than the CZT detectors, appear to permanently solve the inference problem for recycle uranium measurements. In this report, we are comparing the uranium enrichment and holdup measurement performances of a portable NaI detector, a large coplanar-grid CZT detector, and a LaBr3 detector. ACCURATE DETERMINATION OF RADIONUCLIDIC PURITY OF REACTOR PRODUCED 177gLu FOR METABOLIC RADIOTHERAPY L. Canella1, F. Groppi1, M.L. Bonardi1, S. Morzenti1, C. Zona1, Z.B. Alfassi2, M. Chinol3, S. Papi3, G. Tosi3, E. Menapace4 1LASA, Università degli Studi di Milano and INFN-Milano, via F.lli Cervi 201, I-20090 Segrate, Italy; 2Ben Gurion University, Beer-Sheva, Israel; 3European Institute of Oncology, IEO, Milano, Italy. 4ENEA, Division for Advanced Physics Technologies, Bologna, Italy. Thanks to its favorable decay 129 130 13 characteristics, 177gLu (t1/2 = 6.734 d, 100%, E max = 489.3 keV and main E = 208.4 keV, 11%) is starting to find several applications in nuclear medicine, especially for metabolic radiotherapy of cancer and radioimunotherapy. The production of 177gLu is carried out mainly in thermal nuclear reactor. The principal methods of production is either by direct neutron capture reaction 176Lu(n, )177Lu on enriched 176Lu target, or by neutron capture reaction on enriched 176Yb target, followed by negatron decay. While the first method does produce a low specific activity carrier-added (CA) radionuclide, the second method produces a high specific activity no-carrier-added (NCA) one, since 177Yb decays to the ground state 177gLu. Conversely, in this first case the 177gLu is contaminated by the long-lived radionuclidic impurity 177mLu. In this study the accurate determination of radionuclidic purity and half-life of the beta emitter 177gLu used for metabolic radioimmunotherapy is presented. A simple method was developed to distinguish between the different methods available for production of 177gLu. High resolution gamma spectrometry by HPGe and deconvolution of beta decay curve, measured by liquid scintillation counting, has been adopted for quality control of different samples available on the market supplied by nuclear medicine departments. 131 AEROSOL MEASUREMENT USING NEUTRON ACTIVATION ANALYSIS (NAA) Cheryl Olson, Los Alamos National Lab/University of Texas Jon Braisted, University of Texas, Sheldon Landsberger, University of Texas. Open front hoods are routinely used to mitigate a worker's inhalation hazard. However, it has been shown that these hoods leak contaminates, especially when a worker is performing work in the hood. Measurement of the amount of leakage has been primarily qualitative as it is difficult to conventionally measure the small quantity of material (on the order of ?g) leaking from the hood. Quantitative measurement performed in the past does not reflect actually working conditions, but instead tends to conservatively bias the measurement by placing the sampler inside the hood or forcing the airstream out of the hood toward the sampler. In order to accurately measure the amount of material routinely leaking from an open front hood, an air sampler was positioned in front of the hood opening and samples were taken while a routine sample digestion process was done. The digestion process involved the heating of a surrogate mixture to dryness. Samples were taken with and without a worker present during the digestion process. The samples were then analyzed at the University of Texas using neutron activation analysis. The detection level using this method was low enough to measure the amount of aerosol escaping the hood. NUCLEAR DATA AND THE EFFECTS OF ITS INCONSISTENCY ON INSTRUMENTAL NEUTRON ACTIVATION ANALYSIS Y.A. Ahmed; I.O.B. Ewa; I.M. Umar Centre for Energy Research and Training, Ahmadu Bello University, Zaria, Nigeria.. The paper examines the 132 14 role of nuclear data in Instrumental Neutron Activation Analysis (INAA) particularly as it affects reactor irradiation channel characterization and application of comparator methods. The work investigated the available sources of nuclear data, the variations that exist from one source to the other and the effects of such on INAA. Measurement of reactor neutron flux ratio (f) in irradiation channels of a miniature neutron source reactor was carried out using two independent nuclear data sources to demonstrate the dependences of the accuracy of analytical result on careful selection of nuclear data. Values obtained reveal correlation of analytical result of INAA with nuclear data source. It was also observed that modification of the earlier compiled basic nuclear data could lead to inconsistencies in the secondary data that applies them. The end result shows loss of traceability in nuclear data regime. 134 REJUVENATION OF ELECTRON MUTLIPLIERS FOR HIGH SENSITIVITY MASS SPECTROMETRY Hain Oona and Joseph Banar, Los Alamos National Laboratory. The NBS 12-90 mass spectrometer has been utilized extensively in ultra high sensitivity mass spectrometery at the Los Alamos National Laboratory. It has proven invaluable in the analysis of Trans-Uranics and long lived radioisotopes and other isotopic tracers. The heart of the detection system has been the Balzars 317, a 17 stage electron multiplier tube. With time and use the characteristics of the multiplier degrade until it becomes useless. Unfortunately this or equivalent detectors are no longer available.We propose a mechanism for this degradation and suggest a process to rejuvenate these multipliers based on work done by L.A. Dietz. Data are presented that supports the re-establishment of proper operating characteristics of this detector. The same process may be used on other electron multipliers using the beryllium dynode geometry. WET-CHEMISTRY METHOD FOR THE SEPARATION OF NOCARRIER-ADDED 211At/211gPo FROM ALPHA CYCLOTRON IRRADIATED 209Bi TARGET C. Zona,a M.L. Bonardi,a F. Groppi,a S. Morzenti,a E. Menapace,b L. Canella,a Z.B. Alfassi,c K. Abbas,d U. Holzwarth,d N. Gibson,d A. Alfarano,d aUniversità degli Studi di Milano and INFN-Milano, LASA, Radiochemistry Laboratory, via F.lli Cervi 201, I-20090 Segrate, Milano, Italy, bENEA, Division for Advanced Physical Technologies, Bologna, Italy, cDepartment Nuclear Engineering,Ben Gurion University, Beer Sheva, Israel, dIHCP, Institute for Health and Consumer Protection, JRC-Ispra, Varese, Italy. In this study we present a fast and effective wet-chemistry method for obtaining the pure alpha emitter 211At/211gPo (t1/2 = 7.214 h/516 ms) in no-carrier-added form (NCA), produced in K=38 cyclotron by 209Bi( ,2n) reaction. This radionuclide is suitable for high-LET metabolic radiotherapy and immunotherapy (LET = 130 eVonm-1). The method is a selective radiochemical separation of At radionuclides from Bi target and 135 15 210Po impurities, based on dissolution of irradiated target with HNO3, dilution with HCl, extraction with DIPE with a radiochemical yield larger than 98% and back-extraction with NaOH at various concentrations, ranging from 0.09 M to 2.256 M. We obtained a back-extraction yield greater than 90-97% in a range from 0.75 M to 2.00 M. The wet-chemistry method is effective for production of very high specific activity 211At/211gPo, characterized by a radionuclidic purity close to 100 %. In agreement with the energy of the beam, during the separation some picograms or femtograms of At (i.e., some MBq or kBq, due to a AS(CF) of 76 MBq·ng-1) have been separated from 0.20-0.25 g of Bi target with an overall radiochemical yield varying from 10% to 97% vs. NaOH concentration. 136 RESONANCE IONISATION MASS SPECTROSCOPY FOR ELEMENT- AND ISOTOPE-SELECTIVE TRACE ANALYSIS OF ACTINIDES IN ENVIRONMENTAL SAMPLES AND MICROPARTICLES N. Erdmann1, J.V. Kratz1, G. Passler2, N. Trautmann1, K. Wendt2, 1Institute of Nuclear Chemistry and 2Institute of Physics, JohannesGutenberg University Mainz, D-55128 Mainz, Germany. Resonance ionisation mass spectroscopy (RIMS) is based on step-wise resonant excitation and ionisation of atoms with laser light and subsequent mass analysis of the created ions. As the atomic energy level structure is unique for each element, the laser excitation-ionisation scheme is highly specific for each investigated element. Coupled with an efficient mass spectrometric detection of the ions, RIMS combines high element selectivity with low detection limits and the possibility for isotopic composition measurements. This technique has been successfully applied for ultra-trace analysis of actinides and long-lived fission products (such as 99Tc, 90Sr, etc) from environmental and biological samples, as will be illustrated by a few examples. In recent years the analysis of ―hot‖ particles containing actinides has become of great interest for risk assessments of contaminated areas, nuclear forensic analyses and IAEA and Euratom safeguards programs. The state-of-the-art standard technique for their analysis, secondary ion mass spectrometry (SIMS), suffers from isobaric interferences (e.g. 238U/238Pu, 241Am/241Pu). Resonant post-ionisation of sputtered neutrals promises to be an elegant tool to overcome this problem. A new system for resonant laser ionisation of sputtered neutrals from micron-sized particles is currently being set up. First results of the system performance will be presented. STABLE FISSION ISOTOPES FOR INVESTIGATION OF NUCLEAR ACTIVITIES O. T. Farmer III (PNNL), M.L. Thomas (PNNL), G.C. Eiden (PNNL), P. E. Dresel (PNNL) and C. F. Brown (PNNL),. Previous investigations of fission-yield isotopes in the environment have often focused on isotopes with half-lives in the range of hours to years. These are typically of greatest concern from a risk standpoint because they generally exhibit low 139 16 environmental background and are often amenable to analysis by radiometric counting. Investigating a series of stable isotopes produced during nuclear fission provides unique insight into understanding nuclear activities. Our current focus is on analysis by inductively coupled plasma mass spectrometry (ICP/MS) of a series of stable fission isotopes that exhibit high environmental mobility and whose production is sensitive to reactor conditions. For example, ruthenium isotopic abundance distributions from thermal-neutron fission of uranium-235 or plutonium-239 and other materials are distinct from each other and from natural ruthenium isotopic abundance. Thus, isotopic analysis of fission yield ruthenium, molybdenum, palladium and other poly-isotopic elements are hypothesized to provide sensitive indicators of the reactor conditions that lead to the formation of radioactive environmental contamination. By using both open pre-column and on-line ion chromatography (IC-ICP/MS) separations, sample related atomic and poly-atomic interferences in the ICP/MS mass spectra are eliminated and accurate isotopic data can be obtained. 140 ANALYSIS OF IAEA ENVIRONMENTAL SAMPLES BY ICP/MS IN SUPPORT OF INTERNATIONAL SAFEGUARDS O. T. Farmer III (PNNL), M.L. Thomas (PNNL), S.J. Garofoli (PNNL), and K.B. Olsen (PNNL),. The United States Department of Energy and Department of State provides supplemental funding to the US Network of Analytical Laboratories (NWAL) in support of International Atomic Energy Agency‘s (IAEA) Safeguards program. Under this program site specific environmental samples are collected during facility inspection by IAEA inspectors at declared nuclear facilities thorough out the world. The US NWAL system includes Oak Ridge Nnational Llaboratory, Pacific Northwest National Laboratory, Lawrence Livermore National Laboratory, and Los Alamos National Laboratory. The analytical request is a specific listing of gamma emitting radionuclides which includes activation and fission products, and total and isotopic uranium and plutonium. The IAEA reviews the data and based on the results determines if the facility is in compliance with its declaration. In support of this mission a rapid and sensitive method for the isolation and determination of total and isotopic uranium and plutonium by ICP/MS was developed. This method involving a series of redox chemistries and separations using open columns packed with TRU® resin (Eichrom) will be presented. ULTRA TRACE DETECTION OF TH AND U IN COPPER METAL Craig Aalseth (PNNL), Ron Brodzinski (PNNL), Orville Thomas Farmer III (PNNL), Eric Hoppe (PNNL), Todd Hossbach (PNNL), Harry Miley (PNNL) and May-Lin Thomas (PNNL). In order to advance the state of the art in ultra-low-background radiological assay, it is required to develop construction materials with very low concentrations of thorium and uranium (e.g. for thorium <1 microBq/kg or <0.25 pg/g). Reaching this level would allow a germanium gamma spectrometer to operate with greater than 4000 141 17 meters-water-equivalent cosmic shielding and not be limited by materials backgrounds. An on-line hyphenated procedure, SE-ICP/MS (Solvent Extraction-Inductively Coupled Plasma / Mass Spectrometry) has been developed to allow ultra-trace detection (<0.25 pg/g) of thorium and uranium in copper metal. Samples are dissolved using ultra-pure nitric acid, then pumped through an in-line column to extract thorium and uranium while allowing the matrix element components to be diverted to waste. The analytes of interest are then stripped and detected in-line by the ICP/MS as a transient signal. Quantitative results are obtained by using analytical tracers, Th-230 for total thorium and U-233 for total uranium. 142 Low level activity measurement of 131Xem, 133Xem, 135Xe and 133Xe in atmospheric air samples using high resolution dual X-g spectrometry L Gilbert. The detection and measurement of radionuclides released in the frame of nuclear activities is a major task addressing various issues like monitoring of the environment for regulatory requirements or the verification of the compliance with the Comprehensive nuclear Test Ban Treaty (CTBT). In the late‘s 1990s, the French Atomic Energy Commission (CEA) developed a high sensitive technology, capable of performing radioactive noble gas measurements. This device is called SPALAX for Système de Prélèvement d‘air Automatique en Ligne avec l‘Analyse des radioXenons. SPALAX station is equipped with high-resolution dual X and g spectrometry which has been optimised to improve the sensitivity in analysing the radioxenons from environmental samples especially for the metastable ones (131Xem and 133Xem). The full-energy peak (FEP) efficiency curve in the 20-700 keV range has been established with a global uncertainty better than +/- 3% using a Monte Carlo simulation. The Minimum Detectable activity Concentrations (MDC) achievable at the laboratory for 131Xem, 133Xem, 133Xe and 135Xe are presented and the contribution of 133Xe activity on the metastable radioxenon MDC‘s is evaluated. With the very low detection limit afforded by the SPALAX station (less than 1 mBq/m3 in 133Xe) and owing to the nuclear European environment, we present a daily detectable amount of 133Xe in Bruyères le Châtel while the other relevant radioisotopes 135Xe, 131Xem and 133Xem are detected only from time to time. Between August 2003 and August 2005, about eighty peaks with 133Xe atmospheric volumetric activities ranging from ten to a few hundreds of mBq/m3 stand out against a background activity level of some mBq/m3. 143 DEVELOPMENT OF A TRANSPORTABLE SYSTEM FOR RADIONUCLIDE ANALYSIS William C. Cunningham, David L. Anderson, William H. Lamont, Paul K. South (U. S. Food and Drug Administration), Melissa A. Rury, Gregory M. Beachley, John M. Ondov (University of Maryland). In addition to routine regulatory activities and research, the US Food and Drug Administration's 18 Center for Food Safety and Applied Nutrition (CFSAN) is responsible for monitoring and protecting the food supply during emergency situations. Transportable radioanalytical systems were assembled and tested for quantitative determination of gamma-ray emitting radionuclides and screening (qualitative determination) of alpha and beta particle emitting radionuclides, either in house or in alternate or temporary laboratories. Standard operating procedures (SOPs), including instructions for packing, unpacking, assembly, disassembly, calibration, operation, sample collection and analysis, data reporting, and all other procedures needed, were developed. Qualitative beta analyses (planchet, swipe, and tape) were performed on International Atomic Energy Agency Certified Reference Materials (IAEA CRMs) and a variety of foods by using a Tennelec Series 5E Alpha/Beta Analyzer. Five IAEA CRMs and several foods were analyzed for gamma-ray emitting radionuclides by using a Canberra dual hyperpure Ge detector/DSA-100 analyzer/ISOCS software-based system. The SOP for gamma-ray emitting radionuclides was successfully tested at 3 locations by CFSAN personnel with and without experience with nuclear detection techniques and by experienced personnel at the University of Maryland. 144 Availability of Essential Trace elements in Medicinal Herbs used for Diabetes Mellitus and their possible correlations. R. Paul Choudhury1, R. Acharya2, A.G.C. Nair2, A.V. R. Reddy2 and A.N. Garg1*. Herbal medicines have long been in use in various world civilizations for the treatment of chronic diseases including diabetes and heart ailments. Despite tremendous advances in medical sciences during past few decades, there is no cure for chronic diseases such as diabetes mellitus affecting more than 5% of the total urban population. Literature reports suggest that Cr, Zn, Se, Mn, V, Rb and Cs are particularly correlated with diabetes mellitus. To examine the possible role of these elements on curative properties as a first step, we have analyzed 15 plant parts (4 roots, 3 leaves, one flower and 7 fruits & seeds) including 3 commercial brands. Six minor (Na, K, Ca, Cl, Mg and P) and 20 trace (As, Ba, Br, Ce, Co, Cr, Cs, Cu, Eu, Fe, Hf, Hg, La, Mn, Rb, Sc, Se, Sm, Th and Zn) elements were determined by short (1 min) and long (1 d) term thermal neutron irradiations at 1013 n cm -2 s-1 followed by high resolution gamma ray spectrometry. SRMs were used as comparators and for data validation. It is observed that most elements in different herbs vary by a factor of 2 to 5 e.g. Cr (0.59-2.00 mg/g), Zn (28.3-58.9 mg/g), Mn (13.7-73.8 mg/g), Rb (11.0-51.5 mg/g), Cs (57.0-279 ng/g) and Se (73-1044 ng/g). In some herbs, V was also observed in 1-2 mg/g amounts. The fruits and seeds of B. monospeerma, H. isora, T. foenum, S. cuminii, M. charantia and C. cyminum contain higher amounts of Cr (1.60±0.33 mg/g) and Zn (42.8±11.0 mg/g) compared to other plant parts. Strong linear correlations were observed between P and K (r=0.93), Rb and Cs (r=0.92) and Fe and Zn (r=0.89) in all 15 medicinal herbs. One of the most potent herbs C. cyminum, contains elevated amounts of Rb (51.5±1.2 mg/g) and Cs (279±18 ng/g), which have been reported to help breakdown of 19 insulin. Medical reports suggest that diabetes mellitus and hypertension coexist frequently. It is observed that the commercial brands of M. charantia, A. sativun and A. indica contain much higher amounts of Na (838±531 mg/g) and K (28.3±23.5 mg/g). It has been proposed that the elements responsible for diabetes mellitus may remain complexed with the organic macromolecules acting as ligands thus making them bioavailable to our body system. 145 ISOTOPE-AIDED TECHNIQUE IN A FIELD STUDY ON PLANT ROOT BIOACTIVITY Daniele Mascanzoni, DAPIT, Università della Basilicata. An instrumentation and a tracer technique for investigating the root bioactivity in plants injected with Se-75 has been employed in a study carried out under field conditions. The investigation was based on a previously developed instrumentation and on findings that Se-75 is preferably transferred within the root system to the active tissues of the injected plants. The root bioactivity was investigated in corn and sunflower as subjected to different fertilization and irrigation treatments. The pattern of root bioactivity varied with crop, time and treatment applied. The technique showed to be reliable and easy-to-use and the detection equipment scanned the radioactivity along the soil profile with good accuracy. The described method has proved to be a useful tool to study the root response to variations in nutrient and moisture status along the soil profile under field conditions. ADSORPTION BEHAVIOR OF ALKALINE EARTH ELEMENTS ON TERTIARY PYRIDINE RESIN Tatsuya Suzuki, Mayumi Sato, Yasuhiko Fujii. The radioisotope of strontium is one of important indicators for environmental radioactivity. The isotope ratio of stable strontium is used for geochemistry, since strontium-87 is radiogenic isotope from rubidium-87. Thus, strontium is very important element for radioanalytical chemistry. The separation of strontium from other alkaline earth elements is necessary for the precision measurement in both cases. The separation method of strontium using crown ether is well known. However, crown ether is expensive. We proposed new separation method using the tertiary pyridine resin. The adsorption behavior of alkaline earth elements on tertiary pyridine resin was investigated using various type of solvent. We found that strontium can be completely separated from other alkaline earth elements using the tertiary pyridine resin with the methanol nitric acid solution. NEUTRON FLUX VARIATION IN K0-INAA, EXPERIENCES AND SOLUTION IN KAYZERO FOR WINDOWS R. van Sluijs, k0-ware, Heerlen, The Netherlands; D. Bossus, J. Swagten, DSM, Geleen, The Netherlands; A. De Wispelaere and F. De Corte, RUG, Gent, Belgium. The neutron fluence rate can change during the irradiation of a sample for a neutron activation analysis. The cause can be either an 146 147 20 unexpected and unwanted perturbation, a typical variation well known for the irradiation facility or an extraordinary irradiation over several reactors stops in order to achieve the maximum possible neutron fluence in the sample (fluence rate * irradiation time). The k0-method is well suited for handling cases like these in a correct way on the condition that variations of the neutron fluence rate are known over the irradiation period, even in the situation that the thermal to epi-thermal neutron flux ratio is not constant over the irradiation period. Practical, wanted and unwanted situations, consequences and solutions will be discussed. The practical solution as implemented in Kayzero for Windows will be presented. 148 CONCENTRATION OF TECHNETIUM-99 IN INTERNATIONAL STANDARD MATERIALS Yoshihito Ohtsuka, Jyoji Kimura, Yuichi Takaku, Tsutomu Sekine, Shun‘ichi Hisamatsu, Jiro Inaba (IES, Tohoku Nuclear, Tohoku Univ.). Technetium-99 (t1/2=2.1 x 105 y) is one of artificial radionuclides with a long half-life, and has been released into environments from atmospheric nuclear explosions and fuel reprocessing facilities. Recently, 99Tc in an environmental sample has been measured by an inductively coupled plasma mass spectrometer because of its high selectivity and sensitivity for determination of a long-lived radionuclide in comparison with a radiological analysis. However, careful purification of 99Tc is essential for its accurate determination since some elements, such as Mo and Ru, interfere the measurement. We developed an analytical method for trace-level 99Tc in environmental samples. 95mTc free of 99Tc, as a recovery monitor, was produced by irradiation of Nb by alpha-particles from a cyclotron. A known amount of the 95mTc was spiked to the sample, then Tc in the sample was pre-concentrated by using a TEVA disc (Eichrom Industries, US). After Mo and Ru were removed with an anion exchange resin column, 99Tc in the sample was measured by an ICP-MS. We adopted the procedure for the analyses of international standard materials, IAEA-Soil-6, IAEA-375 (soil) and IAEA-381 (seawater), and obtained good results. SEPARATION AND MEASUREMENT OF 126SN IN HANFORD SITE ENVIRONMENTAL SOIL SAMPLES GL Troyer and SA Catlow. Remediation of the legacy nuclear materials at the Hanford site includes characterization of historical tank inventories and environmental soils. Of interest are certain long lived fission product isotopes such as 126Sn. An ion exchange and gamma energy assay method developed for measuring 126Sn in highly radioactive nuclear reprocessing waste has been applied to environmental soils with suspected exposure to process condensate waste streams. The environmental source, sample preparation, elemental separation, measurement results, and detection limit estimate are described. Comparison of MCNP and Experimental Measurements for an HPGe- 149 150 21 based Spectroscopy Portal Monitor Ronald M. Keyser1, Walter Hensley2, Timothy R. Twomey1, and Daniel L.Upp1, 1 ORTEC, 2 PNNL. The necessity to monitor international commercial transportation for illicit nuclear materials resulted in the installation of many nuclear radiation detection systems in Portal Monitors. These were mainly gross counters which alarmed at any indication of high radioactivity in the shipment or the driver. The innocent alarm rate, due to legal shipments of sources and NORM, or medical isotopes in patients, caused interruptions and delays in commerce while the legality of the shipment was verified. To overcome this difficulty, DHS supported the writing of the ANSI N42.38 standard (Performance Criteria for Spectroscopy-Based Portal Monitors used for Homeland Security) to define the performance of a Portal Monitor with nuclide identification capabilities, called a Spectroscopy Portal Monitor. This standard defines detection levels and response characteristics for the system for energies from 59 keV to 1.3 MeV. To accomplish the necessary performance, several different HPGe detector configurations were modeled using MCNP for the horizontal field of view (FOV) and vertical linearity of response over the detection zone of 5 meters by 4.5 meters for 661 keV as representative of the expected nuclides of interest. The configuration with the best result was built and tested. The results for the FOV as a function of energy and the linearity show good agreement with the model and performance exceeding the requirements of N42.38. 151 Improved Performance in Germanium Detector Gamma Spectrometers based on Digital Signal Processing Keyser, Ronald M., Bingham, Russell D., and Twomey, Timothy R; ORTEC; 801 South Illinois Avenue; Oak Ridge, TN 37831. In an HPGe spectroscopy system, Digital Signal Processing (DSP) replaces the shaping amplifier, correction circuits, and ADC with a single digital system that processes the sampled waveform from the preamplifier with a variety of mathematical algorithms. DSP techniques have been used in the field of HPGe detector gamma-ray spectrometry for some time for improved stability and performance over their analog counterparts. Recent developments in HPGe detector construction and new liquid nitrogen-free cooling methods have resulted in HPGe detectors which are better adapted to the needs of the application. Some of these improvements in utility have degraded the spectroscopy performance. With DSP, it is possible to reduce the changes, in real time, in several aspects of detector performance on a pulse-by-pulse basis, which is not possible in the old analog environment. In the past, in designing for the analog regime, flexibility was limited by issues of component size, number and cost. In the digital domain, the problem translates to the need for a DSP with enough speed and an efficient algorithm to achieve the desired transformation or correction to the digitally determined pulse shape or height, event-by-event. The use of DSP allows the peak processing to be tuned to the preamplifier peak shape from the detector 22 rather than being set to an average value determined from several detectors of the type in question. The selection of the filter can be automatic or manual. The following corrections are now possible: ballistic deficit correction, peak resolution improvement by reducing the impact of microphonic noise, increase throughput by reducing pulse processing time, and loss-free (zero dead time) counting. 152 Performance of a Portable, Electromechanically-Cooled HPGe Detector for Site Characterization Ronald M. Keyser and Richard C. Hagenauer; ORTEC; 801 South Illinois Avenue; Oak Ridge, TN 37831. Characterization is a first step to site cleanup or decommissioning of a disused nuclear facility. By definition this initial process must be carried out in-situ. Good knowledge of the inventory of nuclides present, both type and location, is important in the design of an effective plan of remediation. Several systems based on HPGe detectors have been developed, both commercially and at laboratories, and are already in use for this purpose. Such systems are used to perform in-situ measurements in both structures and in the open air. Their use is somewhat complicated by the need for cryogenic cooling of the HPGe detector. Handling of liquid nitrogen in field situations is always difficult. Recent developments in lowpower electromechanical cooling for HPGe detectors have made possible the construction of low weight, portable HPGe spectrometers with sufficient efficiency to perform the needed measurements in reasonable count times, without the need for LN2. A mobile system was modified to use a batterypowered, Sterling-engine cooler on a nominal 40% relative efficiency detector. This system was characterized for efficiency and uniformity of response. The spectrum qualities of efficiency and peak resolution are acceptable for this application. The baseline spectra were analyzed using the DOE EML 1-meter methods to obtain representative MDA values for several nuclides of interest and typical counting times. DETERMINATION OF FISSION PRODUCTS USING GAMMAGAMMA COINCIDENCE AND ANTI-COINCIDENCE COMPTON SUPPRESSION TECHNIQUES Gordon Nicholson, University of Texas at Austin, Nuclear Engineering Teaching Laboratory. Obtaining a detailed description of the various fission products and their relative abundances is important in understanding the fission process. To accomplish this, various techniques must be implemented. One such method is direct measurement of the fission products energy spectra. We measured the fission products decay spectra using gamma-gamma coincidence and anti-coincidence Compton suppression techniques. The Nuclear Engineering Teaching Laboratory at the University of Texas has recently built a new Compton suppression system upon which the detection was carried out. The primary detector of our system is a HPGe crystal which is surrounded by a secondary detector, a NaI scintillator. The two detectors can be operated in coincidence or anti- 153 23 coincidence mode to detect different gammas of interest. Using these methods, a thorough understanding was obtained about the different fission products and the ratios between them. 154 Model-Driven Nuclear Search A.V. Klimenko, K. N. Borozdin, N. W. Hengartner, A. V. Klimenko, W. C. Priedhorsky, B. Tanner. A milligram speck of highly enriched uranium, recovered from the floor of an abandoned facility in the middle of nowhere, might one day provide the evidence to disrupt a deadly nuclear threat. To find that source, which emits just a few dozen alpha-particles and gammarays per second, we are developing a new strategy for efficient nuclear search, moving sensors close to the ground with miniature robots. Because the required size for a nuclear sensor is proportional to the 4th power of source distance our sensors can be small, and therefore cheap, simple and reliable. Wireless multi-agent robotic control will assure precise and controllable movement. From our sensor measurements, we will build and update a radiological map in real time. We propose search by design: starting with a required detection probability and false alarm rate, how do we search neither too little, nor too much? We will update our search strategy as the search progresses. Each detected nuclear particle is a reason to look longer, while each particle not seen is a reason to look elsewhere. Technological advances in robotics allow to minimize the system cost, and replace personnel in risky places with inexpensive expendable mini-robots. As a result, our novel strategy of search combined with miniature robotic technology, driven by a real-time model of the radiation environment, promises to revolutionize radiological survey techniques, making them faster, safer and more sensitive. Fusing Signatures of Different Physical Processes in Muon Tomography A.V. Klimenko, C.L. Morris, W.C. Priedhorsky, K.N. Borozdin, L.J. Schultz. Muons, as well as other types of radiation, loose their energy while propagating through matter. Resulting attenuation of cosmic muon flux was successfully used to radiograph large-scale objects. During their passage through matter charge particles also undergo multiple scattering. It was demonstrated that based on the measured scattering angle, the information about the material (that the muon passed through) can be extracted and the presence of small-scale high-Z objects can be identified. Additional hints on the structure of radiographed object can be gained from electro-magnetic showers produced by natural background radiation. The showers are more likely to originate from high-Z objects. Muons that are stopped in the material form muonic atoms in their excited state, and undergo de-excitation through Auger and radiative transitions. The energy of muonic X-rays produced in such radiative transitions are characteristic of material the muonic atom was formed in. Combining data from all of the processes discussed above may provide more information on the structure of the object and allow for reduced exposure times and more efficient tomography. We 155 24 report on our effort to fuse the signatures of different physical processes and the information they provide about the radiographed objects. 156 NEW METHOD FOR THE EVALUATION OF ATOMIC BOMB NEUTRTONS OF HIROSHIMA AND NAGASAKI USING AG-108M Kazuhisa Komura, Low Level Radioactivity Laboratory, K-INET, Kanazawa University. Highly sensitive method using 108mAg (half-life: 418 y) alternative to using 152Eu was discovered for the evaluation of Atomic-Bomb neutrons of Hiroshima and Nagasaki. 108mAg have never been considered in the evaluation of Atomic-Bomb neutrons, because cross section of the 107Ag(n,gamma)108mAg reaction is 1 barn, which is only about 1/6000 of the 151Eu(n, gamma)152Eu reaction. Nobody including the author has not noticed that number of target atom (107Ag) is million times higher than 151Eu atoms in granite rocks containing only about 1 ppm Eu. If we consider abundance of gamma rays from 108mAg (434, 615, 723 keV), decay of 152Eu during 60 years after the bombing, we can calculated the merit of 108mAg measurement 3 orders of magnitude higher than 152Eu measurement.We succeeded to detect intense gamma rays from 108mAg in silver decoration exposed at 450m from the hypocenter of Hiroshima. Furthermore, 108mAg could be detected by ultra lowbackground gamma ray measurement at Ogoya Underground Laboratory in the brass ring of AtomicBomb victimﾕ s finger, spoon, sword guards, pocket watch etc, all of which contain trace amount silver as metal contaminant indicating extremely high sensitivity of the 108mAg method. If silver items such as finger ring or rosary are available, neutron dose of the victim can directly be evaluated up to about 1.6 and 1.4 km from the hypocenter of Hiroshima and Nagasaki, respectively. 108mAg method can be applied more than 1000 years, which is to be compared with only 60 years of 152Eu method. 157 MODELING OF GAMMA-RAY SPECTRA TO DIRECT EFFICIENT CHEMICAL SEPARATIONS Matthew Douglas, Judah I. Friese, Glen A. Warren, Paula P. Bachelor, O. Tom Farmer III, Andrea D. Choiniere, Shannon M. Schulte, Craig E. Aalseth. In an age of increasing terrorist nuclear threats, rapid and robust analytical methods for the quantification of radionuclides in mixed fission product samples are needed to provide forensic information and sample characterization. Measurement of characteristic gamma emissions by highpurity germanium spectrometers offers one means of analysis. Due to the complex nature of samples, chemical separations are necessary to reduce background continuum levels and instances of spectral interference. A project has been initiated at Pacific Northwest National Laboratory (PNNL) to model singles and coincident gamma spectra that would result from various chemical separation strategies. The goal is to use these complementary counting techniques to tailor a series of efficient chemical 25 separations, allowing the rapid quantification of signature isotopes in samples. This project is part of a larger effort to refine the laborious and time-consuming series of radiochemical separations traditionally used to isolate individual elements prior to analysis. Improvements in detector technology have led to additional pathways of analysis which can reduce the time required for sample processing. Modeling allows us to define the temporal window of detection for radionuclides following a given chemical separation. These data will aid in decision making for the processing of real samples. A description of results to date will be presented, demonstrating the utility of this approach for improved processing and analysis of mixed fission product samples. 158 USING ADVANCED ALGORITHMS AND FASTER PROCESSING TO OBTAIN BETTER AUTOMATIC ISOTOPE IDENTIFICATION RESULTS Benjamin Sapp, Robert Estep, Mohini Rawool-Sullivan, Clair Sullivan, Los Alamos National Laboratory;. Two prototype handheld gamma spectrometers are being developed for secondary screening of cargo and personnel. These instruments will have significantly more processing power than previous instruments allowing them to become a test bed for many advanced algorithms that have been run only on the PC before because of handheld system constraints. Both of these instruments will use a similar physical package and electronics. One instrument will use NaI(Tl) as the detector material, while the other will use a LaBr3(Ce) scintillator. We plan on using fuzzy logic algorithms perfected in the Los Alamos GN series of instruments as well as use the multiple isotope material basis set method (MIMBS) algorithm which has never been implemented on a handheld identifier before because of system constraints. The planned hardware and software algorithms will be discussed. REDOX SEPARATION OF IODIDE FROM HALIDES IN PREPARATION FOR THERMAL IONIZATION MASS SPECTROMETRIC (TIMS) ANALYSES OF RADIOIODINE MD Engelmann, LA Metz, and NE Ballou; Pacific Northwest National Laboratory. Radioiodine analysis by TIMS suffers from preferential ionization of higher electron-affinity halogens. Because of this, successful TIMS analysis of iodine requires halogen separation. Recovery experiments on a mixed halide solution using 125I tracer indicate that redox-based separations are capable of isolating iodine from chlorine and bromine by preferential oxidation of the iodide/iodine redox pair. This vastly facilitates subsequent separation efforts in that the iodide is oxidized to the elemental chemical state while the remaining halides are left in the reduced form. Subsequently, the unique volatility of the iodine may be exploited for additional separation and isolation from remaining matrix components through the use of a purge and trap system, which has the additional benefit of maintaining the unique micro-sample handling techniques required for 160 26 TIMS filament loading chemistry. Both chemical and electrochemical oxidation methods were utilized and parameters were optimized for maximizing both the iodine recovery and the halide separation factors. 160 ELECTRODEPOSITION OF TECHNETIUM ON PLATINUM FOR THERMAL IONIZATION MASS SPECTROMETRY (TIMS) MD Engelmann, NE Ballou, LA Metz, and MH Engelhard, Pacific Northwest National Laboratory; and JE Delmore, Idaho National Laboratory. A Novel device has been fabricated for the electrodeposition of technetium metal onto platinum filaments for Thermal Ionization Mass Spectrometric (TIMS) measurements. The ability of the device to focus the deposition to diameters of hundreds of micrometers on pre-mounted TIMS filaments coupled with the ease of use and simplicity of design permit for an extremely sensitive yet economical TIMS filament loading technique. Electrodeposition parameters were varied in order to maximize deposition efficiency. X-ray Photoelectron Spectroscopy (XPS) and Secondary Ion Mass Spectrometry (SIMS) were used to confirm and characterize the technetium deposit. The technetium is deposited in the metallic state, although surface oxides in the 4+ and 7+ state form readily. Initial TIMS measurements of the electrodeposited technetium in the presence of a barium sulfate ionization enhancer suggest the potential for excellent sensitivity. Efforts to spatially align the barium sulfate deposit for maximum overlap with the technetium deposit are underway. Characterization of Aging and the Ethanol Effects in relation to the Minerals Concentration in Bone samples by EDXRF. InayáLima1, Marcelino Anjos2, Monica Rocha3, Ricardo Lopes1.1- Nuclear Instrumentation Laboratory, COPPE, UFRJ, Brazil;2- Physics Institute, UERJ, Brazil;3 – Pharmacology Institute, CCS, UFRJ, Brazil.. One of the most types of X-ray fluorescence instrumentation available is the Energy dispersive X-ray fluorescence (EDXRF). This technique is based on the real time generation, detection and measurement of X-rays emitted by the elements in a sample. The analytical process is non-destructive, requires little sample preparation, can be performed in minutes and permits the simultaneous collection of the whole spectrum. The mineral in bone plays important roles in the dynamic equilibrium between the intake elements and their availability locally and systematically. Minerals have been shown to have a profound influence on the chemistry and solubility of bone mineral as the skeleton is the target organ for many heavy metals. The objective of this study is determined the elementals concentrations in bone, in several regions of femur samples. It was used six samples, measured in triplicate, in different ages, with and without ethanol treatment. The samples were placed in the experimental setup, irradiated by 1500s and the spectra were recorded by a Si(Li) detector. A total of ten elements were detected, including essential like Ca, S, Cl and K and trace like Fe, Zn, Sr, Rb, Mn, Cu and Ni. The results tells that the EDXRF is a non-invasive powerful technique able to 161 27 characterization bone samples and the subject becomes important to hope the investigation once more about the elemental contribution in the bones. 162 PROBALISTIC UNCERTAINTY ESTIMATOR FOR GAMMA SPECTROSCOPY MEASUREMENTS Frazier Bronson Canberra. Gamma spectroscopy is a very powerful tool to determine the radioactivity of various items, such as samples in the laboratory, or waste assay containers, or large items in-situ. However, in order to properly interpret the quality of the result, an uncertainty estimate must be made. This uncertainty estimate should include the uncertainty in the efficiency calibration of the instrument, as well as many other parameters. For many kinds of measurements, especially those on items that have not been carefully prepared for laboratory gamma spectroscopy, it is the efficiency uncertainty that is the dominant component to the total propagated measurement uncertainty. Efficiency calibrations have traditionally been made using traceable radioactive sources, but recently mathematical calibrations have been shown to be accurate to within 5%, very fast, and more convenient. But whether mathematical or source-based calibrations are used, any deviations between the as-calibrated geometry and the as-measured geometry contribute to the total uncertainty. This paper will show the use of automated mathematical calibrations to evaluate and propagate the reasonably expected variations between calibration and measurement. This includes variations in container wall thickness and diameter, sample height and density, sample non-uniformity, sample-detector geometry, and many other variables. A probabilistic technique combining all the variables is used. 163 DISTRIBUTION AND TRANSPORT OF LONG-LIVED SOLUBLE FISSION PRODUCTS Pihong Zhao, Qinhong Hu, Timothy P. Rose, Gregory J. Nimz* Chemical Biology and Nuclear Science Division, Lawrence Livermore National Laboratory, 7000 East Avenue, L-231, Livermore, CA 94550, * AEES, Energy & Environment Directory, Lawrence Livermore National Laboratory, 7000 East Avenue, L-396, Livermore, CA 94550. A total of 828 underground nuclear tests were conducted at the Nevada Test Site (NTS) between 1951 and 1992, depositing >1018 Bq of radioactivity in the subsurface environment. Approximately one-third of these tests were conducted below the water table, posing a potential long-term risk to the water resources in this area. The fission products technetium-99 and iodine129 are of particular concern to risk assessment models due to their long half-lives and high mobility as aqueous anionic species. To better understand how the 99Tc and 129I radiological source terms transform into hydrological source terms, we have analyzed groundwater and nuclear test debris samples from underground nuclear test cavities at the NTS. Isotope dilution ICP-MS and liquid scintillation counting were used for 99Tc analyses, and ICP-MS 28 and accelerator mass spectrometry methods were used to measure 129I. In this presentation, we will discuss the distribution of these radionuclides in the nuclear test cavity environment, comparing the observed activities in test debris samples (glass and rubble) with those found in near-field groundwaters. This work was funded by the Underground Test Area Project, National Nuclear Security Administration, Nevada Site Office. Work was performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under contract W-7405-Eng-48. 164 TRACE ELEMENTS DISTRIBUTION IN BENIGN BREAST DISEASES FIBROADENOMA MEASURED BY INSTRUMENTAL NEUTRON ACTIVATION ANALYSIS ABUGASSA, I. O., ABUGASSA, S. O., DOUBALY, K. , BASHIT, T.A. (RENEWABLE ENERGY AND WATER DESALINATION CENTER). This paper focuses on the determination of the elemental distributions in specimens of benign breast disease (fibroadenoma tumors). The concentrations of more than 20 elements in breast sample tissue taken from 18 pre-menopauses age patients (15-45 years) were determined. The analytical method employed was Instrumental Neutron Activation Analysis based on k0-method. All the samples were irradiated in Tajura Research Reactor under thermal flux ~ 1013 n/cm2 s for 8 hours. The levels and distribution of the elements in the samples investigated are analysed and discussed. The reliability of the analysis was checked with several biological reference standard materials. Our results was also compared with literature value. Transport of Plutonium at the Nevada Test Site, NV A.B. Kersting, M. Zavarin, P. Zhao, E. Ramon, L. Shuller, S. Roberts, M. Johnson and R. Williams. Glenn T. Seaborg Institute, Chemistry & Materials Science, Lawrence Livermore National Laboratory, PO Box 808, Livermore, CA 94550. email: Kersting@llnl.gov. Colloidal- or colloidalbound transport of plutonium (Pu) and other low-solubility radionuclides has been observed in groundwater and surface water. At the Nevada Test Site groundwater contaminated with radionuclides associated with underground nuclear tests was collected from several different well locations. In each case, the low-levels of plutonium detected in the groundwater were overwhelmingly associated with the colloidal and not the dissolved fraction of the groundwater. The colloidal fractions consisted of secondary minerals such as clays and zeolites. The majority of the actinides deposited in the ground after an underground nuclear test reside in melt glass sequestered at the bottom of the test cavity. To better understand the mechanisms controlling the release and transport of actinides from melt glass, glass dissolution experiments on nuclear melt glass were conducted. The glass alteration material was characterized using radiography, scanning electron microscopy and transmission electron microscopy. The minerals formed from the glass dissolution are consistent with the colloid mineralogy 165 29 observed down-gradient and suggest that Pu is released from the melt glass as the secondary colloids minerals form. This work was performed under the auspices of the U.S. Department of Energy by University of California, Lawrence Livermore National Laboratory under Contract W-7405-Eng-48. 167 Environmental Applications of Stable and Radioxenon Monitoring P. Evan Dresel, Khris B. Olsen, James C. Hayes, Justin I. McIntyre, and Scott R. Waichler from Pacific Northwest National Laboratory and B. Mack Kennedy of Lawrence Berkeley National Laboratory. Improved detection capabilities are needed at several Department of Energy sites to make remedial decisions about facilities and landfill cleanup. For facility monitoring air samples can be collected from within a facility and analyzed for short lived radioxenons to estimate inventories of residual plutonium holdup within the facility. For landfill cleanup activities soil gas sampling for xenon isotopes can be used to define the locations of spent fuel and transuranic wastes. Short-lived radioxenon isotopes are continuously produced by spontaneous fission of plutonium-240 in transuranic wastes. Large volume soil-gas samples provide extremely sensitive measurement of radioxenon in the subsurface; a characteristic of transuranic waste. The analysis employs a modified Automated Radioxenon Sampling and Analysis (ARSA) system. Proof of principle measurements at a Hanford Site liquid waste disposal site showed xenon-133 at levels in soil gas are approximately 16,000 times the detection limit and lower levels of xenon-135 from the spontaneous fission of plutonium-240 were also measured. Stable xenon isotopes are also produced by spontaneous fission but are subject to background concentrations in ambient air samples (facilities) but less so in soil gas where free exchange with ambient air is restricted. Rare gas mass spectrometry is used for highly precise stable xenon isotopic measurements. Stable xenon isotopic ratios from fission are distinct from natural xenon background ratios. Neutron capture on xenon-135 produces an excess of xenon-136 above fission ratios and thus provides a means of distinguishing reactor sources (e.g. spent fuel) from separated transuranic materials (plutonium). MEASUREMENTS OF CO2 LEAKAGE FROM UNDERGROUND SEQUESTRATION FIELDS USING RADIOACTIVE TRACERS Bachelor, P. P., McIntyre, J. I., Amonette, J. E. Foster-Mills, N. S., Hayes, J. C., Milbrath, B. D., Saripalli, P., Pachific Northwest National Laboratory. Reduction of anthropogenic carbon dioxide (CO2) release to the environment is a pressing challenge that must be addressed to avert the potential devastating effects of global warming. Within the United States, the most abundant sources of CO2 emissions are those generate from coal- or gas-fired power plants; one method to control CO2 emissions is to sequester it in deep underground geological formations. From integrated assessment models the overall leakage rates from these storage locations must be less than 0.1% of stored volume per year for long-term control (1). The ability to 168 30 detect and characterize nascent leaks, in conjunction with subsequent remediation efforts, will significantly decrease the amount of CO2 released back into the environment. Because potential leakage pathways are not necessarily know a priori, onsite monitoring must be performed; the monitoring region in the vicinity of a CO2 injection well (2) may be as large as 100 km2, which represents the estimated size of a supercritical CO2 bubble that would form under typical injection scenarios. By spiking the injected CO2 with a radiological tracer, it will be possible to detect ground leaks from the sequestered CO2 using fewer sampling stations, with greater accuracy than would be possible using simple CO2 sensors. The relative merits of various radiotracers, detection methods and potential interferences will be discussed. (1) Dooley, J. J. 2002. "Why Injecting CO2 Into Various Geologic Formations is not the Same as Climate Change Mitigation: The Issue of Leakage." Sixth International Conference on Greenhouse Gas Control Technologies, Research Institute of Innovative Technology for the Earth, To be Published. (2) Saripalli, P. and P. McGrail. 2001. "SemiAnalytical Approaches to Modeling Deep Well Injection of CO2 for Geological Sequestration." Energy Convers. Manag. 43(2):185-198. The Information Release (IR) request for document PNNL-SA-47249 has been approved by all the reviewers. 169 Investigation of a new wide dispersion multiple collector isotope ration mass spectrometer design Anthony. D. Appelhans*, James. E. Delmore, John. E. Olson. A full scale prototype of a new design for a wide dispersion thermal ionization multicollector isotope ratio mass spectrometer has been constructed and tested. The results of tests with both the full scale prototype and a small-scale prototype instrument are presented. The measured performance of the smallscale prototype sized for 6Li and 7Li and the performance of the full scale prototype with 85Rb and 87Rb is compared with the predictions of a SIMION ion optical model. The ion optical model is shown to accurately predict the measured mass dispersion, mass resolution, and general ion beam profile. The new design includes a single magnetic sector and an electrostatic dispersion lens to magnify the mass dispersion so that full sized discrete dynode electron multipliers or Daly detectors can be used to simultaneously monitor each isotope. A concept is presented for a thermal ionization instrument capable of simultaneous measurement of seven isotopes in the 240 dalton mass range. PLUTONIUM ISOTOPIC MEASUREMENTS AND URANIUM ENRICHMENT MEASUREMENTS USING LaCl3(Ce) AND LaBr3(Ce) GAMMA-RAY DETECTORSA Mohini W. Rawool-Sullivan (N-2), John P. Sullivan (ISR-1) and Tracy R. Wenz (N-1), Los Alamos National Laboratory, Los Alamos, NM 87545, USA. Nondestructive analysis (NDA) techniques such as calorimetry, passive gamma-ray analysis, and neutron coincidence counting are widely 170 31 used for nuclear safeguards and material control. Quantitative interpretation of some of these measurements (e.g. of radiation or heat) requires knowledge of the isotopic composition (or isotopics) of the material. Gamma-ray spectroscopy with high-resolution detectors is a well-developed NDA technique for isotopics. The use of cryogenically cooled intrinsic germanium detectors for isotopics measurements of in situ material is at times very difficult because of severe access limitations. This is where portable instruments that will do isotopics are needed. 171 LARGE-SAMPLE ACTIVATION ANALYSIS –PROCESS MONITORING USING RADIOANALYTICAL METHODS C. Segebade, M. Hedrich, L. Giese, W. Goerner and C. Adam, Federal Institute for Materials Research and Testing, Berlin, Germany. Along with the globally increasing energy demand the application of renewable energy sources is urgently required. Using photovoltaic sources (PV), this can be achieved. However, to save material resources, and to minimise undesirable landfill recycling of spent PV modules is necessary. Therefore, the converting layer (CdTe in this study) was removed from the glass carrier using different methods, e.g. sandblasting, and separated subsequently from the blast material (e.g. corundum) and other components using stepwise different separation techniques. The separation and enrichment of CdTe was performed by water-based flotation. Several floating procedures were studied regarding their separation yields. The respective distribution of CdTe in the phases involved (flotate, water, residue) was measured using EDXRS with different spectrometry setups, among these a miniaturised mobile spectrometer equipped with a small, electrically cooled CdTe diode for low energy photon spectrometry.. The aforementioned material samples were also analysed by instrumental large-volume photon activation analysis (IPAA) as a reference procedure. The results of both analytical methods were in satisfactory agreement. In the future application on the industrial scale, IPAA or another high-precision method is intended to be used for iterative intermediate analytical quality control. NATURAL RADIOACTIVITY IN PHOSPHATE CONTAINING FERTILIZERS USED IN AUSTRIA Katzlberger Christian, Korner Martin Austrian Agency for Health and Food Safety. Natural radioactivity mainly due to 40K, 238U- and 232Th-chain nuclides in about 300 phosphate containing fertilizer samples (> 5% phosphate content) as well as in raw phosphates used and (partly) produced in Austria has been measured by high resolution gamma-spectrometry and ICP-MS in the last 3 years within a monitoring project. The results for the content of uranium (determined via 234mPa and ICP-MS), 226Ra (via 214Pb and direct measurement), 210Pb, 232Th (ICP-MS), 228Ra (via 228Ac), 212Pb, 227Th and 40K in the raw phosphates and fertilizers used in Austria are presented in detail and are compared to world wide mean values. The radiological impact of the use of fertilizer products on environment, 172 32 agricultural areas, crops and food chain is discussed with regard to the mean contents of natural radioactivity in Austrian soils. 174 AN EXPLORATORY DATA ANALYSIS FOR PLUTONIUM CONTAMINATION Hiromu Kurosaki, Robert Radford**, James Filliben*, and Kenneth G. W. Inn, NIST Physics Laboratory, NIST *Statistical Engineering Laboratory; **University of California, Santa Barbara. With over 70% of the earth surface covered in water, monitoring the quality of our ocean is one of the most important tasks in science today. Both shellfish and seaweed have been shown to be effective indicators of the ocean quality. One of the overall goals of our group is to develop environmental radioactivity standard reference materials such as soil, sediment, and vegetation. However, a problem arose when the blank for shellfish analysis, a sample containing nothing but tracer solution, began to show Pu activity indicating contamination. It is essential that the analytical blank be as low as possible because the massic activity of the plutonium in the shellfish is extremely low and a reliable certified value is needed for the Standard Reference Material. This project is utilizing a systematical engineering experimental design, which tries to narrow down and isolate the source of contamination from sixteen different variables that occurs throughout the experimental process. The potential sources of contamination range from the fume hood to the glassware, and reagents used. Ordinarily, well over 256 experiments would have been performed in order to isolate the point of contamination. Since this is not an efficient use of resource, an experimental design was made using Exploratory Date Analysis (EDA). EDA narrowed an unfeasible 256 experiments to a very manageable 32. The set is then further subdivided into 4 sets of 8, based on the use of reagents. The experimental design made it possible to identify the sources and interactions of cources of contamination in a timely and cost effective manner. ON-SITE COLLECTION, CONCENTRATION AND SEMIQUANITIFICATION OF NUCLIDE SPECIFIC ANALYTES IN URINE John S. Morton*, Robert D. Timm, James B. Westmoreland, General Engineering Labs, LLC, Charleston, South Carolina 29407. A procedure and device are described that allow the on-site concentration and separation of nuclide-specific analytes in a one-time voiding of urine. Present collection methods require that bulk (one to two Liter) urine samples be collected on-site and shipped to a remote laboratory before the analytical procedure is begun. The transit time between shipping and the initiation of analysis allow many complex and irreversible reactions to transpire. In order to destroy the resulting matrix, the sample is treated aggressively with harsh chemicals in a time-consuming procedure to force the separation of the target nuclide. The paper describes a method, including the reaction vessel, into which the sample is introduced followed by the addition of acid and 175 33 denaturing agents. Nuclide-specific resins added to the container separate and concentrate the analyte(s) of interest by mass action. The retention of various target nuclides is a function of acid, denaturing agent and resin(s). The resin(s) is (are) retained as the remaining sample is discarded. Sample volumes are reduced to approximately 20-30 mL. Application to the emergency management of an uncontrolled release of radioactivity is discussed. Extension of the method and device coupled with on-site instrumentation is considered with estimated detection limits for the protection of first responder personnel and the affected population. Variations of the sample-collection device design and analytical method are protected by the U.S. Patent Office. 175 INVESTIGATION OF RADIOACTIVITY IN SELECTED DRINKING WATER SAMPLES FROM MARYLAND Iisa Outola1, Svetlana Nour1, Hiromu Kurosaki1, Kenneth Inn1, Larry Lucas1, Peter Volkovitsky1, Jerome La Rosa1, Kevin Koepenick2, 1NIST, 100 Bureau Drive, Gaithersburg, MD 20899-8461, 2Baltimore County Department of Environmental Protection and Resource Management, Towson, MD, USA 21204. In 2004, levels of radioactivity exceeding federal drinking water standards were found in two separate areas of Maryland by state laboratories charged with the responsibility for overseeing water quality. In one case, the level determined from gross alpha and beta screening measurements was not accounted for by more specific analyses for uranium and radium concentrations in that water. In a second case, occurring in a different area of the state, elevated levels of radioactivity in the water supply system were likewise observed by gross activity screening. In both cases, it was desired to know which radionuclides were responsible for the activity. Additionally, in the second case, authorities there wanted to know what effect water softener systems installed in individual households had on mitigating the problem. NIST was contacted by the State of Maryland and provided additional radiochemical analyses that were instrumental in addressing both situations. Non-destructive gamma spectrometry and gross alpha-beta liquid scintillation measurements, as well as chemical separations followed by measurements of 222Rn, 226Ra and 228Ra, uranium and thorium isotopes, 210Po and 210Pb were carried out. The results of the studies indicated disequilibrium among the decay products in the Th and U decay chains had a major influence on the radionuclide content in the drinking water, and that mitigation using a water softener was not equally effective for all radioelements. DRAFT UNCERTAINTY ACCEPTANCE CRITERIA DERIVED FROM HISTORICAL PERFORMANCE TESTING RESULTS James Filliben, Kenneth G.W. Inn, NIST, Gaithersburg, MD; James Dahlgran, Mary Verwolf, David Sill, RESL, Idaho Falls, ID; Keith McCroan, USEPA/NAREL,Montgomery, AL. The NELAP Performance Testing subcommittee on Radiochemistry has been considering the 177 34 application of ANSI N42.22 test criteria as an indication of acceptable radioanalytical capabilities. The ANSI N42.22 test criteria asks that the difference between the laboratory result and the reference value (supported by measurement traceability links to NIST) be less than three times the combined standard uncertainty of that from the laboratory and the reference laboratory. This effort will provide the users of the PT exercises with a quantitative link between measurement results and the confidence in the results. One potential problem is that the laboratory could have an unusually high probability of passing the PTs when its reported uncertainty is larger than expected. The NELAP PT Radiochemistry subcommittee has been evaluating establishing upper bounds to the uncertainties reported by the laboratories based on recent historical results being collected by the PT Provider for a limited number of drinking water gamma-ray emitting radionuclides, radium isotopes, uranium, and 90Sr. For other radionuclides in additional matrices to water, the DOE/RESL Multi-Analyte Performance Evaluation Program (MAPEP) has historical data that was mined in this study to draft additional bounds of uncertainties. While individual studies indicated that the percent difference from the reference value was best characterized by symmetrical distributions, there was study to study fluctuations in distribution location. The weighted method was used on the residuals to characterize the 99 percent confidence level uncertainty function for each radionuclide in each matrix. The derived uncertainty limits are compared to historical results to verify appropriateness. 179 DEVELOPMENT OF THE NIST ROCKY FLATS SOIL STANDARD REFERENCE MATERIAL (SRM) Svetlana Nour, Kenneth G.W. Inn, NIST, 100 Bureau Drive, Gaithersburg, MD 20899-8462. The International Committee on Radionuclide Meteorology (ICRM) recognized the need for a supply of natural matrix standards in sufficient quantities and varieties for quality control purposes at the user level at the first meeting of the Low-Level Measurement Techniques Group in1976. A natural matrix standard was defined as a standard of radioactivity which is homogeneously contained in a matrix in the same chemical forms that are found in the environment. The SRM is intended for use in tests of measurements of environmental radioactivity contained in matrices similar to the sample. Since 1906, SRMs have been used by NIST as a vehicle for transferring measurement science and technology throughout the scientific community, industry, and commerce. SRMs are key tools for verifying important measurement results, developing new measurement methods, and providing users with tools to assist in establishing traceability of measurement results to NIST. The standard reference material (SRM) of the soil was chosen to be the soil from near the Rocky Flats Plant in northcentral Colorado because this soil fulfills the criteria of low organic – low carbonate content, the contamination concentrations of a number of transuranics are fairly well-known, and the logistics and costs of obtaining the samples and shipping were reasonable. In order to certify massic 35 activitie of radionuclides in the Rocky Flats Soil SRM, NIST sent to experienced laboratories five plastic bottles with 100 g of soil, and a set of NIST tracer solutions. Eight laboratories reported their data, and the analysis of this data is in progress. The content of the following radionuclides in the soil were reported: 238Pu, 239&240Pu, 241Pu, 241Am, 238U, 234U, 235U, 228Th, 230Th, 232Th, 234Th, 226Ra, 228Ac, 137Cs, 210Pb, 214Pb, 214Bi, 208Tl. 180 GETTING INTO THE BOMAB HEAD Matthew Mille, University of Maryland, College Park, MD 20742; Svetlana Nour, NIST, 100 Bureau Drive,Gaithersburg, MD 20899-8462. In the event of a radioactive disaster, one of the biggest tasks is to estimate the radiation dosage received by people to determine the actions of emergency response teams. As part of these radiation dosage calculations, accurate measurements of the contaminated people require an estimated geometrical efficiency based on the measuring equipment of the human body. This implies that there is a need for a large number of human body standards (phantoms) to meet the quality criteria of the measurement. The purpose of this project was to find a reliable way to estimate the efficiency of gamma systems using the Monte Carlo computation, and to validate that efficiency by making measurements of a standard geometry. The final scope of the project is to create a standard human body phantom, to validate its theoretical efficiency based on a comparison of the Monte Carlo computation with the experimentally measured efficiency, and to calibrate existing phantoms. A Bottle Manikin Absorption (BOMAB) phantom head spiked with Ga-67 was used for this project as a standard geometry. The radioactive BOMAB head is measured at a number of distances from HPGe detector, and the experimental efficiency for our gamma spectrometry system is determined. The same set of experiments is then modeled using the Monte Carlo N-Particle Transport Code (MCNP). The main task for the MCNP calculations is to create an accurate and realistic description of the measuring system (detector, source, and the environment). In this project, a method is proposed to define the object‘s geometry by using its CT scan data. A computer program called Scan2MCNP was used to convert CT scan data of the BOMAB head into a very accurate 3-dimensional computer model to be included into the MCNP input file. The project output will make it possible to measure similar geometries with unknown activity using the estimated efficiency by MCNP based on its CT images. The theoretical and experimental results are compared. The results of the project that is currently in progress will be reported: 1) results between computations and measurements are consistent to better than 4 percent, 2) the uncertainties for both computations and measurements are better than 4 percent (k=1), 3) the major uncertainty for the MCNP computations was the description of the geometry of head-detector system, and 4) the major uncertainty for the measurements was the emission probability of the gamma-rays. 36 181 DYNAMICS OF ELEMENTAL COMPOSITION DURING NEURONAL DEATH IN MUTANT-MICE BRAINS MONITORED WITH NEUTRON ACTIVATION ANALYSIS K. KRANDA, J. KUCERA (Nuclear Physics Institute and Research Centre, Ltd., Rez, Czech Republic), J. Baeurle (Charite - Universitaetsmedizin, Berlin, Germany). Neutron activation analysis was used to monitor elemental compositions of discrete murine brain structures with mass as low as 0.5 mg. Our investigation encompassed two murine mutant types, weaver and Lurcher. These mutations express channelopathy, a condition also observed in several human neurological disorders, including presumably Parkinsonism. Both mutants show two disparate spatio-temporal patterns of neuronal loss in the cerebellum that is never seen in the wild-type mice that served as controls. Elevated zinc and copper concentration, observed in the mutant cerebella, closely followed the time course of neurodegeneration. In the forebrain of weaver and Lurcher, with no documented pattern of neurodegeneration, zinc and copper concentration approximate those values observed for the wild-type. Other elements, (Na, K and Rb), show a celldeath related elevation in the cerebella but only in weaver. Their time course, seen in Lurcher, roughly follows the pattern observed in the wild-type mice. In conclusion, the time course of neurodegenerative processes closely matches those elevated zinc and copper composition of afflicted brain regions. The disparity of other elemental concentration, in particular that of Na, K and Rb observed in the cerebella of weaver and Lurcher points out the possible difference in cell death processes operating in these mutants. RADIOCHEMICAL MEASUREMENT OF 237NP ACTIVITY CONCENTRATION IN A MIXED RADIONUCLIDES SOLUTION I. Outola, J. La Rosa, E. Crawford; Ionizing Radiation Division, National Institute of Standards and Technology. A radiochemical procedure was developed for the measurement of 237Np activity concentration (1 – 10 Bq/g range) in a solution containing comparable activities of other actinides (230Th, 234U, 238U, 238Pu, 240Pu and 241Am) and significantly greater activities from 60Co, 90Sr and 137Cs. Photon emissions of 237Np and its daughter 233Pa were not directly visible from this mixture. Short-lived, gamma-emitting 239Np (t1/2 = 2.356 d) was used as the yield monitor after ―milking‖ it from ca. 22 kBq of 243Am. Weighed aliquots of the freshly separated and purified 239Np solution were added to the sample solutions. One aliquot was prepared as a comparator in 5g of 2M HNO3 solution in a sealed glass ampoule. After radiochemical exchange between 237Np and 239Np, co-precipitation and extraction chromatography techniques were used to chemically separate Np. Final sources used for both gamma and alpha spectrometry were prepared by co-precipitation of Np with 50 µg of Nd as NdF3. Calibrations of (1) the gamma spectrometry system for 239Np relative geometry between ampoule and NdF3 sources and (2) the alpha spectrometry system for the absolute geometry of 237Np-NdF3 sources were carried out. Results, advantages and disadvantages of the procedure are 182 37 presented 183 New Applications of Gamma Spectroscopy: Characterization Tools for D&D Process Development, Inventory Reduction Planning & Shipping, Safety Analysis & Facility Management During the Heavy Element Facility Risk Reduction Program Mark Mitchell*, Lennox Harris, Reginald Gaylord, Robert Vellinger, Michael West, Jennifer Larson, Brian Anderson, Leonard W. Gray, Greg Jones Lawrence Livermore National Laboratory. This presentation discusses the development of new applications for gamma ray spectroscopy for D&D process development, inventory reduction planning and shipping, safety analysis and facility management. These applications of gamma spectroscopy were developed and implemented during the Risk Reduction Program (RPP) to successfully downgrade the Heavy Element Facility (B251) from a Category II Nuclear Facility to a Radiological Facility. Gamma spectroscopy is concluded to be an important tool in project management, work planning, and work control (expect the unexpected and confirm the expected), minimizing worker dose, and resulting in significant safety improvements and operational efficiencies. Inventory reduction activities utilize applications of gamma spectroscopy to identify and confirm isotopics of legacy inventory, in growth of daughter products and the presence of process impurities; quantify inventory; prioritize work activities for project management; and supply documentation satisfying shipping/receiving requirements. D&D activities utilize applications of in situ gamma spectroscopy to identify and confirm isotopics of legacy contamination; quantify contamination levels and monitor the progress of decontamination; and determine the point of diminishing returns in decontaminating enclosures and glove boxes containing high specific activity isotopes such as 244Cm and 238Pu. In situ gamma spectroscopy provided quantitative comparisons of several decontamination techniques (e.g. Stripcoat TLC, Radiac wash, acid wash, scrubbing) and is used as a part of an iterative process to determine the appropriate level of decontamination and optimal cost to benefit ratio. Facility management utilizes applications of gamma spectroscopy, in conjunction with other characterization techniques, process knowledge, and historical records, to provide information for work planning, work prioritization, work control, and safety analyses (e.g. development of hold points, stop work points, and bounding hazard analysis); and resulted in B251 successfully achieving Radiological status. Gamma spectroscopy helps define operational approaches to achieve ALARA, e.g. hold points, appropriate engineering controls, PPE, workstations, and time/distance/shielding. Applications of gamma spectroscopy can improve similar activities at other facilities. PERFORMANCE EVALUATION OF SPECTRAL DECONVOLUTION ANALYSIS TOOL (SDAT) SOFTWARE USED FOR NUCLEAR EXPLOSION RADIONUCLIDE MEASUREMENTS 184 38 Dr. Kendra M. Foltz Biegalski (UT), Dr. Steven Biegalski (UT), and Mr. Derek Haas (UT). The Spectral Deconvolution Analysis Tool (SDAT) software was developed to improve counting statistics and detection limits for nuclear explosion radionuclide measurements. SDAT utilizes spectral deconvolution spectroscopy techniques and can analyze both b-g coincidence spectra for radioxenon isotopes and high-resolution HPGe spectra from aerosol monitors. Spectral deconvolution spectroscopy is an analysis method that utilizes the entire signal deposited in a gamma-ray detector rather than the small portion of the signal that is present in one gamma-ray peak. This method shows promise to improve detection limits over classical gamma-ray spectroscopy analytical techniques; however this hypothesis has not been tested. To address this issue, we performed multiple tests to compare the detection ability and variance of SDAT results to those of commercial-off-the-shelf (COTS) software which utilizes a standard peak search algorithm. In the first test, small 137Cs peaks were superimposed on the Compton continuum of a 60Co spectrum (~10,000 counts per channel in the Compton continuum around the 137Cs peak region) and we compared how well each software package detected the small peaks. For the second test, we determined the variance properties of several sparse 137Cs spectra (entire spectra have ~1000 counts each). 185 STATISTICALLY ROBUST INTERCOMPARISON REFERENCE VALUES FOR THE CERTIFICATION OF THE NIST SEAWEED RADIONUCLIDE STANDARD REFERENCE MATERIAL James J. Filliben1, Iisa Outola2, Kenneth G.W. Inn2; Statistical Engineering Division1 and Ionizing Radiation Division2; National Institute of Standards and Technology. Over the past twenty-five years, NIST has developed various low-level radionuclide Standard Reference Materials (SRM) such as bone ash, soil, sediment, human lung and liver. Certified massic activities of the radionuclides in the SRM's are determined by a carefully evaluated intercomparison of experienced laboratories. Twenty four laboratories from 15 countries participated in the certification of the seaweed SRM. Each participating laboratory received five 300 g bottles of seaweed and set of NIST tracer solutions. Laboratories were asked to provide at least one result from each bottle for each radionuclide they have considerable radioanalytical experience. Data were received for following radionuclides: 239+240Pu, 239Pu, 240Pu, 238Pu, 241Am, 237Np, 99Tc 210Po, 210Pb, 137Cs, 40K, 90Sr, 238U, 234U, 235U, 230Th, 232Th, 228Th, 226Ra, 228Ra, 228Ac, 234Th, 212Bi, 214Bi, 214Pb, 14C, 129I, 3H, and 208Tl. Several different statistical techniques were evaluated for calculating reference values from laboratories‘ values including mean, weighted mean, midmean, median, Type B On Bias (BOB), Graybill-Deal, Mandel-Paule, Vangel-Rukhin and Maximum likelihood. After reviewing the results from all these techniques, the median was chosen as the most robust way to calculate the reference values. The uncertainties for the certified values were estimated using bootstrap analysis. Thirteen radionuclides were certified, and information 39 value was provided for 15 radionuclides. 186 ATOM-AT-A-TIME STUDIES OF THE TRANSACTINIDE ELEMENTS Darleane C. Hoffman, Nuclear Science Division, Lawrence Berkeley National Laboratory, and Department of Chemistry, University of California, Berkeley, California 94720. Some of the techniques of radioanalytical chemistry that have been applied to atom-at-a-time investigations of both the nuclear and chemical properties of the transactinide elements (Z>103) will be discussed.. Although the currently known transactinides were all discovered using physical (nuclear) techniques, the first isotopes that were discovered for elements 107 through 112 had half-lives of only milliseconds. Consequently, studies of their chemical properties awaited discovery and availability of isotopes with half-lives long enough for chemical separations and decay properties suitable for verifying the atomic number of the detected events. Measurements of energies, half-lives, and time correlations of known alpha-alpha decay chains provide an ideal method for establishing atomic number. Some of the constraints on the chemical systems that are valid for exploring chemical properties when only a few atoms at a time are available and recent developments in instrumentation will be reviewed. The current status of studies of the chemical properties of the elements through hassium (108) will be reviewed and the prospects for exploring the chemical properties of still heavier elements and their predicted properties will be presented. TRACED FISSION PRODUCT ANALYSIS Friese, Judah I; Douglas, Matthew; Farmer III, Orville T; Bachelor, Paula P; Schulte, Shannon M; Thomas, May-Lin, Pacific Northwest National Laboratory. Rapid chemical separation techniques have been developed and evaluated for their use in the quantitative analysis of mixed fission product samples. An effort to streamline and optimize the separation and detection of fission products has been undertaken, and various alternative chemical separation techniques have been tested. These include self assembled molecular monolayers (SAMMs), extraction and cation-exchange chromatography, and solvent extraction. The use of tracers for quantification of chemical yield by neutron deficient radioisotopes and/or isotopically enriched stable elements has been evaluated. The integration of radiation detection and mass spectrometry for rapid analysis offers benefits to some chemical systems. Examples of this integration for selected systems will be presented. A description of the analytical methods for separations and tracing will be presented for fission product analysis. LOW-LEVEL GAMMA-RAY SPECTROMETRY FOR ENVIRONMENTAL SAMPLES Pavel P. Povinec, Comenius University, Faculty of Mathematics, Physics 187 188 40 and Informatics, Mlynska dolina F1, SK-842 48 Bratislava, Slovakia. Lowlevel gamma-ray spectrometry with large volume HPGe detectors has been widely used in environmental radioactivity measurements. The reasons are an excellent energy resolution and high efficiency that permits selective and non-destructive analyses of several radionuclides in composite samples. Although the most effective way of increasing the sensitivity of a gamma-ray spectrometer is to increase counting efficiency and the amount of sample, very often the only possible way is to decrease the detector‘s background. The typical background components of a low-level HPGe detector, not situated deep underground, are cosmic radiation (cosmic muons, neutrons and activation products), radioactivity of construction materials, radon and its progenies. Monte Carlo simulations have shown that the dominating background component is due to cosmic muons, therefore an effective anticosmic shielding is required when measuring present levels of radionuclides in the environment. Characteristics of single, coincidence, anti-cosmic and anti-Compton spectrometers designed for different applications will be compared and discussed. The present state of the art low-level gamma-ray spectrometers require at least partial shielding provided by underground installations. 190 THE USE OF COLLODION FILMS TO PROTECT SOLID STATE ALPHA DETECTORS FROM HEAVY ION RECOILS Barry D. Stewart, CEMRC/NMSU; Edward Hall, University of Rochester; Kenneth G. W. Inn, NIST. Alpha-recoil contamination of solid state alpha spectrometry detectors leads to inaccurate measurements due to increased backgrounds, larger measurement uncertainty, and decreased sensitivity (increased detection limit). In addition, since recoil contamination is permanent, and cannot be practically removed, detectors used for sensitive measurements may have to be replaced long before their useful life has been reached. This problem was addressed in 1970 by Claude Sill and Dale Olson, Analytical Chemistry 42, 1596-1607 (1970). Their approach used a Cartesian diver to control the pressure, and thus the amount of air present in the spectrometer chamber, in order to provide an absorber to stop the recoiling nuclei. In addition they applied a -6 volt bias to the source plate. However, the Cartesian diver approach is not very practical in large-scale applications. Several vendors have added adaptations of this approach to commercially available instrumentation, but there are many situations where older equipment is being utilized that does not have any type of recoil suppression system. As an alternative, we have developed and tested thin collodion (polymer) films as a mechanism to greatly reduce or eliminate recoil contamination. We present evidence to suggest that the mechanism by which these films stop recoil ions is impact energy loss. Atomic Force Microscopy (AFM) was used to plot surface topography and impact damage on the films. In addition, we present results obtained from the use of thin films to demonstrate that the use of thin films is highly successful in the prevention of recoil contamination. 41 191 USING MCNPX(TM) TO MODEL PHYSICALLY LARGE PROBLEMS W. K. Hensley, S. M. Robinson, Pacific Northwest National Laboratory. MCNPX(TM) has been used to model the effect of scattered gamma radiation produced by a VACIS® rail gamma-ray-imaging system when it is located near the type of Radiation Portal Monitor (RPM) installed at international borders. Several aspects of the physics and geometry of the problem make the modeling task challenging. Specifically, because only scattered radiation reaches the RPM, and the distances involved are on the order of 100 feet, only a very few of the primary photons emitted from the source will be scattered and transported to the gamma-ray sensors in the RPM. Although some variance reduction can be achieved by source biasing, source biasing alone does not overcome the effect of the large distances and resulting small solid angles involved in the problem. MCNPX(TM) (version 2.5.0) has implemented variance reduction for pulse height tallies (via importance splitting), which when combined with source biasing, allows large scale problems to be evaluated in a timely manner. The results of the calculations will be compared to experimental measurements. MULTIELEMENT ANALYSIS OF BONE FROM THE OSTEOGENESIS IMPERFECTA MODEL (OIM) MOUSE USING THERMAL AND FAST NEUTRON ACTIVATION ANALYSIS. C. E. Buff1, S. M. Carleton2, D. J. McBride5, C. T. Winkelmann3, C. L. Phillips4, and J. S. Morris1. 1University of Missouri Research Reactor Center, Columbia, MO 65211, USA; 2Genetics Area Program, Departments of 3Veterinary Pathobiology, and 4Biochemistry, University of MissouriColumbia, Columbia, MO; 5Division of Endocrinology, Diabetes and Nutrition, University of Maryland, Baltimore, MD.. Osteogenesis imperfecta (OI) is a heritable form of osteoporosis caused, in almost all patients, by mutations in one of the genes (COL1A1 or COL1A2) that encode the proα chains of type I procollagen. Type I procollagen mutations can change the structure and/or biosynthesis of type I procollagen, and ultimately alter the mineralization of bone. As in other monogenic disorders, it has been well recognized that the same OI mutation can exhibit significant differences in phenotype severity. The variation in disease severity suggests a role for genetic modifiers. Long term objectives of this study involve using the oim mouse model of OI to evaluate both the impact of the mutation and the role of the genetic background on bone mineralization. Tibias from mice with the oim mutation were evaluated using thermal and fast neutron activation analysis. Tibias from wildtype (WT), heterozygous (+/oim) and homozygous (oim/oim) animals were subjected to four INAA experiments using the MURR pneumatic-tube irradiation facility. Elements measured in order were F (exp 1), P (exp 2), Na, Mg, Cl, and Ca (exp 3) and K and Zn (exp 4). Details of the INAA experiments and impact of the type I collagen mutation on bone mineralization will be discussed. 193 42 194 DOCUMENTATION OF A MODEL ACTION PLAN TO DETER ILLICIT NUCLEAR TRAFFICKING David K. Smith, Michael J. Kristo, Sidney Niemeyer (Lawrence Livermore National Laboratory) and Gordon B. Dudder (Pacific Northwest National Laboratory). Theft, illegal possession, smuggling, or attempted unauthorized sale of nuclear and radiological materials remains a worldwide problem. The International Atomic Energy Agency's (IAEA) Illicit Trafficking Database reports that between 1995 and the end of 2004 more than 650 incidents have been confirmed by 82 participating member states. In response, international cooperation has increased in the area of nuclear forensics and attribution. In partnership with the IAEA, the Nuclear Smuggling International Technical Working Group (ITWG) promotes the science and techniques of nuclear forensics. In 2000 the ITWG adopted a Model Action Plan to encourage prosecution of these crimes through a systematic approach to nuclear forensics. National authorities subsequently successfully tested the concept in the Czech Republic, Hungary, Bulgaria, and the Ukraine. In order to disseminate information on a response to incidents of illicit trafficking, the Model Action Plan was fully documented at the request of the IAEA and provides recommendations concerning incident response, collection of evidence to appropriate legal standards, laboratory sampling and distribution of samples, radioactive materials analysis including categorization and characterization of samples, forensics analysis of conventional evidence, and case development including interpretation of forensic signatures. The availability of the Model Action Plan reference to requesting governments and the sharing of technical and information resources on nuclear forensics and attribution is an essential tool to deter illicit trafficking. 196 DETERMINATION OF PHOSPHOROUS IN ORGANIC MATERIALS BY INSTRUMENTAL PHOTON ACTIVATION ANALYSIS (INAA) W.Goerner, Chr. Segebade; M. Ostermann, O.Haase Federal Institute for Materials Research and Testing ,Berlin, Germany. Phosphorous is one of the prominent hetero-atoms in organic compounds. Therefore an instrumental determination is an alternative to chemical separation. 31P(γ, n)30P seems promising. Unfortunately, oxygen is present in many organic compounds. 16O (γ, n) 15O leads to a positron emitter with a half life of 122,2 s being rather close to that of 30P (T1/2=149,9s). This makes gamma-spectrometric decay curve analysis unreliable. The way out of this ―selectivity trap‖ is the direct beta measurement of the positrons. 30P offers a maximum beta energy of 3.24 MeV compared with 1.73 MeV by 15O. This is a really discriminating feature. Moreover, the carbon interference by 12C (γ, n) 11C can be avoided by irradiation with sub-threshold photon energy of 18MeV. By chance, this measure also decreases the production rate of 15O in comparison to that of 30P. Preliminary experiments resulted in 20.000 43 cts/mg P after 10 irradiations above a near-zero background, compared with only 3 cts/mgO. This ratio may encourage to use gamma-spectrometry for samples with a supposed O:P-ratio less than 100. It can be concluded, that direct positron measurement as well as the choice of the irradiation energy are selectivity features of IPAA in this case. 197 THE PERFECTION OF LOSS-FREE COUNTING G. P. Westphal and H. Lemmel. Atominstitut der Oesterreichischen Universitaeten, Stadionallee 2, A-1020 Vienna, Austria. Short-lived isomeric transitions and a fast rabbit system, high rate gamma spectrometry and Loss-Free Counting are the corner stones of Rapid Automatic Neutron Activation Analysis which has been reported on at the last Kona Conference. Programmed in assembler language on a fast PC, the system has sufficient speed reserves to allow among others for combined multi-spectra, multichannel and multi-scaling analysis including the calculation of individual loss-correcting weighting factors for all events up to input counting rates of up to 106 c/s. Counting loss correction is based on the method of Computed Pileup Correction where hardware-generated dead-time correction factors are totalized for the purpose of loss-corrected multi-scaling and, at the same time, produce weighting factors from a look-up table, to perform dead-time and pileup-corrected multi-channel analysis. Up to now, a common look-up table has been used for all events corresponding, in conventional Loss-Free Counting, to one common dead-time extension time. Usually, such systems are optimized for perfect loss-correction of a reference sample with a single energy. Higher energies exhibit under-correction, lower energies overcorrection to degrees depending in their extent on the pulse processing system and its baseline occupancy for different energies. To give a simple explanation: smaller energies have narrower pulses which in turn have better chances to avoid pulse pileup. Negligible for long shaping times, this effect may lead to correction errors of several percent in high-rate systems where charge collection times in the detector become a significant contribution to total pulse processing.In our present system, for the first time, individual energy-dependent pileup correction factors are calculated for all events by means of an original algorithm, making it what very probably may be called the first perfect implementation of Loss-Free Counting.Experimental evidence for the performance of the new system is given over the whole range of counting rates (up to 106 c/s) and counting losses (up to 99%). Temporal response is tested by means of short-lived isomeric transitions and a fast rabbit system with or without the use of the pulsed mode of our TRIGA reactor. A Remote Handled Radial Micro-Gamma Scanning Device Mark Huntley, Battelle Energy Alliance. A device has been designed, built and tested that allows for the measurement of Cs-137 across the diameter of a fuel segment. This device was designed and tested at the Idaho National Laboratory, Materials and Fuels Complex, operated by Battelle Energy 198 44 Alliance. Although the data is preliminary, it appears that the Cs-137 composition in the matrix can be quantified along the radial profile of a fuel segment. Using micro-columnation and shielding, a 3/8" diameter fuel segment is scanned in ten increments of 0.0375" each. This measurement and its propagated uncertainty are an improvement over the current state of the art techniques which plot relative activity or relative intensities. Most, however, simply measure the fission products around the circumference of a segment and then use software to extrapolate the composition to the center. (References will be provided on poster). The device dimensions and its application will be presented. The path of the gamma emissions through the columnation will be shown. The affect the shielding has on adjacent Cs-137 on the quantity measured will be presented as well as some correction factors that can be used. Efficiency data will be presented along with plans for future improvements. 199 Fast Neutron Induced Fission Neutron Spectra Below The Incident Energy Mitchell Woodring, James Egan, Gunter Kegel, Parrish Staples, David DeSimone. Fission neutron spectra from neutron induced fission in 235-U and 239-Pu for energies below that of the neutron inducing fission have been measured. The spectra were obtained for 1.5 MeV and 2.5 MeV incident neutrons. Previous accelerator-based fission neutron spectra measurements have been seriously complicated by time-correlated gamma rays and scattered neutrons from the fission sample. Three barium fluoride detectors were placed near the sample undergoing induced fission and used to identify fission gamma rays. A coincidence of fission gamma rays was used to gate a liquid scintillator detector to distinguish fission events from other events. The fission neutron spectral shape and average energy measured in this experiment compare well to both previous measurements and prior theory and also suggest a dependence on incident neutron energy and mass of the fissioning nucleus. An overview of the experiment, a discussion of the results, and the importance of this work to homeland security are given . LOW-LEVEL COINCIDENCE-ANTICOINCIDENCE GAMMA-RAY SPECTROMETRY P.P. Povinec, I. Sýkora, R. Janik, S. Tokár, K. Holý, M. Chudý, M. Ješkovský, Comenius University, Faculty of Mathematics, Physics and Informatics, Mlynska dolina F1, SK-842 48 Bratislava, Slovakia. Analyses of anthropogenic and natural gamma-ray emitters in the environment require high sensitive detector systems operating in coincidence-anticoincidence modes. Thanks to an excellent energy resolution and a high efficiency, large volume HPGe detectors have ben widely used in low-level gamma-ray spectrometry. In the present paper we discuss characteristics of various coincidence-anticoincidence (HPGe-NaI(Tl)) arrangements suitable for analysis of environmental samples containing cascade gamma-emitters (e.g. Co-60), positron emitters (e.g. Na-22) and single gamma-ray emitters (e.g. 200 45 Cs-137). The detectors were placed in the large volume shield consisting of (from outside to inside) 10 mm of iron, 100 mm of lead, 50 mm of copper, 80 mm of polyethylene with boric acid, 1 mm of cadmium, 1 mm of copper and 10 mm of plexiglass. The top of the shield is strengthened by additional 100 mm of iron. The inner dimensions of the shield are 800x900x1700 mm, and the total weigth is around 18 000 kg. Boric acid and cadmium has been used for absorption of neutrons. The efficiency of the HPGe detector (relative to a 76 mm diameter and 76 mm long NaI(Tl) detector) is 70 %, the energy resolution for 1.3 MeV gamma-rays of Co-60 is 2.1 keV. The reduction of background for the single gamma-ray spectrometer is between 60 and 250, depending on the gamma-ray energy. The contribution of radon daughters to the detector background has been eliminated by flushing the shield by old air and nitrogen gas from the Dewar. For coincidence measurements two NaI(Tl) detectors (100 mm and 200 mm in diameter, and 100 mm and 200 mm long, respectively) were tested. The larger crystal had a well of 80 mm in diameter and 80 mm deep. Better results were obtained using the well detector because of its higher counting efficiency (although its energy resolution was worse). An anti-cosmic shielding has been realised using a plastic scintillation detector placed above the HPGe detector. Characteristics of single, coincidence, anti-cosmic and anti-Compton spectrometers designed for different applications will be compared and discussed. 201 NAIL RESONSE TO SIMULTANEOUS INTAKE OF Se AND Hg IN A RAT MODEL J. D. Brockman,1,2 J. D. Robertson,1,2 J. S. Morris,2 C. Ralston,3 N. Ralston.3 1. Department of Chemistry, University of Missouri, Columbia, MO, 65211 2. University of Missouri Research Reactor, Research Park Drive, Columbia MO 65211 3. Energy and Environmental Research Center, Grand Forks, ND 58202-9018. The nail is routinely used as a biomonitor for the essential trace element selenium (Se). The purpose of this study was to examine the robustness of nail mercury (Hg) and Se as biomarkers of dietary intake. Dietary Se supplementation protects against MeHg toxicity that occurs when inorganic Hg released from methyl-Hg (MeHg) selectively binds Se, limiting its bioavailability and inhibiting its enzymatic functions. This mechanism appears likely to disrupt the deposition of Se in nails. Weanling male Long Evans rats were fed torula yeast based diets containing 8, 80 or 800 ppb Se prepared with either 0, 0.10 or 15 ppm Hg MeHg continually for 63 days. Rat nails were collected on day 63 and analyzed using INAA. The Se concentration in the nail is well correlated (r2 > 0.90) with dietary Se in every Hg supplementation group and good correlation (r2 > 0.80) is observed between dietary MeHg and nail Hg concentration in the three Se groups. The mean nail Se concentration in the 15 ppm Hg group was lower than the 0 and 0.10 ppm Hg groups in all three Se diets. The observed decrease was, however, only significant (p < 0.002) in the 80 ppb Se diet. 46 202 Elevated Uptake of Th and U by Netted Chain Fern (Woodwardia areloata) Anna Sophia Knox* and Daniel I. Kaplan, Savannah River National Laboratory, Aiken, SC, and Tom Hinton, Savannah River Ecology Lab., Aiken, SC. This paper focuses on Th and U uptake by netted chain fern (Woodwardia areloata) from contaminated soils. A field screen study and a greenhouse study were conducted to assess the ability of selected plant species to extract U and Th form contaminated soils. The study site was an ecologically sensitive wetland located on the U.S. Department of Energy's Savannah River Site near Aiken, South Carolina. The contaminated and uncontaminated soils from the study site were used in the greenhouse study. Thorium concentrations in both studied soils were high, 201 and 329 mg kg1, respectively in soil A and B. Uranium content in these soils varied considerably, ranging between 10.7 and 1016 mg kg-1, with a mean concentration 284 mg kg-1. The bioavailability of Th and U was estimated by the concentrations of these elements in DTPA extracts. Thorium and U DTPA-concentrations were low or very low, 7.9 and 0.27 mg kg-1, respectively. Evaluation of various phosphate sources for the remediation of uranium contaminated soils and sediments. Anna Sophia Knox*, Daniel I. Kaplan, and Robin Brigmon, Savannah River National Laboratory, Aiken, SC, USA. Uranium is a significant contaminant on the Savannah River Site (SRS) in Aiken, South Carolina and at several other Department of Energy sites. Radionuclides that contaminate water, soils, or sediments cannot be destroyed, but the toxicity of these inorganic contaminants can be diminished through alteration of their chemical speciation. Ideally, such chemical alterations (e.g., reduction or precipitation) will convert toxic and mobile species to nontoxic and immobile species. The use of sequestering agents for transformation of radionuclides in low concentrations in the contaminated soils offers considerable potential for long-term environmental cleanup. Gamma-ray and Neutron Signatures for State-of-health Analysis and Monitoring of Widely-arrayed Radiation Portal Monitor Systems Mitchell Woodring, James Ely, Melany Eslinger, Jill Pospical, Edward Ellis, Terre Mercier. Pacific Northwest National Laboratory has deployed a large array of radiation portal monitors for the Department of Homeland Security and US Customs and Border Protection. These portal monitors scan incoming vehicles crossing the US border and shipping containers leaving international ports for radioactive material via gamma-ray and neutron detection. Data produced and captured by these systems are recorded for every vehicle related to radiation signature, sensor/system status, and local background, as well as a host of other variables. Within the Radiation Portal Monitor Project at PNNL there is a need to develop state-of-health (SOH) 203 205 47 observation and analysis for the whole RPM system using these data to determine functionality and performance. Recent efforts to develop SOH algorithms, important data to use in SOH monitoring, the impact of SOH monitoring, and some preliminary results from implementing SOH checking are reported. 206 HISTORY OF THE PLUTONIUM BIOASSAY PROGRAM AT THE LOS ALAMOS NATIONAL LABORATORY, 1944-2006 D. W. Efurd1, R. E. Steiner1, S. P. LaMont1, D. Lewis2, 1. C-INC: Isotope and Nuclear Chemistry, 2 HRS-4: Health Physics Measurements, Los Alamos National Laboratory, Los Alamos, NM, 87545, USA. In 1944 Los Alamos National Laboratory (LANL) instituted a program for the collection and analyses of urine samples from individuals working with plutonium. This program has operated continuously for over 60 years. During that time the plutonium bioassay program incorporated advances in urine sample collection, radiochemical separation techniques, alpha spectroscopy and thermal ionization mass spectrometry measurement techniques as well as cleanroom technology. All of these advances have produced incremental improvements in plutonium detection limits. A chronological description is given of the methodologies used in the plutonium bioassay program at Los Alamos. Special emphasis is placed on the cleanroom chemistry operations and thermal ionization mass spectrometric measurement techniques developed from 1997-2006 that enabled LANL to simplify chemical processing while at the same time obtaining lower limits of detection for plutonium in urine. MULTI-POINT RADIATION MONITOR K. J. Hofstetter and D. M. Beals. A unique radiation monitor has been developed for performing wide-area field surveys for radiation sources. This device integrates the real-time output of multiple radiation detectors into a hand-held personal computer (e.g., a PDA) containing an intuitive graphical user interface. An independent hardware module supplies high voltage to the detectors and contains a rapid sampling system for transferring the detector count rates through an interface to the PDA. The imbedded firmware can be changed for various applications using a programmable memory card. As presently configured, the instrument contains a series of Geiger-Mueller (GM) tubes in a flexible detector string. An immediate alert is sounded and the detector identified when any of the radiation levels exceed preprogrammed limits. The instrument is powered by rechargeable batteries with a minimum of 8-hours of operation. The data acquisition and display unit weighs ~20 ounces and is housed in a shock-proof and water resistant case. The technology utilizes unique sensor node designs that minimize complexity, manufacturing and repair costs with maximum reliability. The present flexible linear array of multiple sensors has been demonstrated to US Coast Guard and Customs inspection personnel by measuring radiation 207 48 intensity in stacks of transport containers where physical access is impeded. This instrument would improve their mission of intercepting radiological weapons of mass destruction in commercial cargo vessels. This monitor could be deployed as a simple portal monitor for screening passengers and small packages for radioactive material. It could also be used to perform wide-area searches for lost radiation sources by sweeping the area with the detector string. 208 URANIUM DETECTION USING SMALL SCINTILLATORS IN A MARITIME ENVIRONMENT K. J. Hofstetter, D. M. Beals, D. M. Odell, D. L. Dunn, and M. E. Farrar. A systematic study of the performance of several commercially available radiation detection instruments containing NaI or CsI detectors has been performed at SRNL. Hand-held radiation detection equipment containing small scintillators are routinely used by field inspection personnel to detect and identify the transport of uranium as a deterrent to undeclared nuclear proliferation or nuclear terrorism. The detection of uranium in a variety of chemical forms and isotopic enrichments present some unique challenges and opportunities in the maritime environment. This study was conducted using a variety of shielded and unshielded uranium sources in a simulated maritime environment. The results include estimates of the detection sensitivity for various isotopic enrichments and configurations using the manufacturer's spectral analysis firmware. Additional off-line methods for analyzing the spectra are evaluated to determine the absolute detection limits. Suggested improvements to the existing spectral analysis algorithms are presented to enhance the field detection of illicit nuclear material. A combined method for the determination of the isotopic vector of Plutonium isotopes in environmental samples E. Hrnecek1, R. Jakopič2, A. Wallner3, P. Steier3 1ARC Seibersdorf research GmbH, 2444 Seibersdorf, Austria 2Jožef Stefan Institute, Ljubljana, Slovenia 3Institut für Isotopenforschung und Kernphysik der Universität Wien, VERA Laboratory, Währinger Str. 17, 1090 Vienna, Austria . A combination of Alpha Spectrometry, Liquid Scintillation Counting and Accelerator Mass Spectrometry (AMS) was used for the determination of the isotopic vector of Plutonium isotopes in environmental reference samples and samples contaminated from nuclear reprocessing. After chemical separation and adding Pu-236 tracer, samples for Alpha Spectrometry were prepared by microprecipitation with NdF3 using cellulose nitrate membrane filters. The Pu-236 tracer was used to determine the absolute specific activity. The activity ratio Pu-238/(Pu-239+Pu-240) was determined by Alpha Spectrometry. Pu-241 was determined from a part of the same filters by LSC. The remaining part of the filter was used for measurement of the isotope ratio Pu-240/Pu-239 by AMS at the Vienna Environmental Research Accelerator (VERA) facility. An overview on the isotopic vector of the 210 49 samples will be given and the capabilities and detection limits achievable will be discussed. 211 THE CONDITIONALITY OF SMELS REFERENCE MATERIALS FOR QC/QA OF K0-NAA IMPLEMENTATION F. De Corte(1), P. Vermaercke(2), P. Robouch(3). (1)Laboratory of Analytical Chemistry, Institute for Nuclear Sciences, Ghent University, Proeftuinstraat 86, B-9000 Gent, Belgium; (2)SCK-CEN, Mol, Belgium; (3)IRMM, Geel, Belgium. . Recently, synthetic multi-element standards (SMELS) were released, for QC/QA of the NAA k0-standardization method after its implementation in a laboratory [1]. Type I, II and III materials are available, yielding via (n,gamma) activation short-, medium- and long-lived radionuclides, respectively. All three types consist of a phenol-formaldehyde resin matrix, homogeneously doped with a selection of elements for which ―reference‖ concentrations and their uncertainties are provided. When looking at the first applications of the SMELS, it was observed that occasionally the analysts were at some important points not following the ―instructions for use‖. Therefore, in order to avoid any further misinterpretation of their properties and hence any further invalid conclusions from their employment, the present paper reviews the conditionality of the SMELS materials for QC/QA. Basically, it should be realized that SMELS were developed for investigating the ―correctness of implementation‖ of the k0-method. Here, the most crucial steps are the calibration of the Ge-detector and of the irradiation facility. Therefore, the choice of the doping elements, and of the radionuclides and gamma-rays where the reference concentrations are based upon, was such that: 1) the gamma-lines in the spectrum show no interference and have all but the same peak area – thus minimizing uncertainty contributions from gamma-spectrum analysis; 2) activation reactions with largely different epithermal-to-thermal contribution were incorporated; and 3) gamma-rays ranging from low to high energies were involved. Clearly, in these circumstances unambiguous information can be obtained as to the correctness of the calibration of the detector (detection efficiency versus gamma-ray energy) and of the reactor site (thermal-to-epithermal neutron flux ratio). Evidently, the above considerations only hold on condition that the SMELS are analyzed via the same radionuclides and gamma-lines, and using the same ―recommended‖ k0 and related nuclear data, as those that were involved in the characterization of the material. If not, traceability is lost and conclusions become invalid. These and other features and aspects of the conditionality of the SMELS, the information on which was rather fragmentary available in former publications, are comprehensively dealt with in the present paper. [1] P. Vermaercke, P. Robouch, M. Eguskiza, F. De Corte, G. Kennedy, B. Smodiš, C. Yonezawa, H. Matsue, X. Lin, M. Blaauw, J. Kučera (presented at 4th k0 Workshop, Madeira, 2005), Nucl. Instr. Methods A, submitted. 50 212 NEUTRON ACTIVATION ANALYSIS FOR IDENTIFICATION OF AFRICA MINERAL DUST TRANSPORT S.M. Almeida1, M.C. Freitas1, C.A. Pio2,1Instituto Tecnológico e Nuclear, Apartado 21, E.N.10, 2686-953 Sacavém, Portugal, 2Departamento de Ambiente e Ordenamento, Universidade de Aveiro, 3Laboratório de Análises Ambientais e Controlo de Qualidade, INETI, Portugal. A Gent stacked filter unit sampler was used to collect Air Particulate Matter (APM) in separate coarse (PM2.5-10) and fine (PM2.5) size fractions at a sub-urban site in Lisbon, Portugal. The samplings were done during the year 2001 and two daily samples were taken per week. The samples were analyzed for particulate mass and up to 24 elements by INAA and PIXE. The analysis of APM levels in the fine and coarse fraction and the study of the atmospheric dynamics by back-trajectories show that most of the PM2.5 and PM2.5-10 peaks events were associated with a transport of air masses from the Saharan desert. High mineral load in ambient particulate matter levels were registered during the Saharan dust outbreaks. The accuracy of INAA to measure Fe, Sc and Sm was evaluated with NIST filter standards, revealing results with an agreement of ± 10%. Therefore, this method was used as an important tool for the identification of these events. IN-FIELD DATA MANAGEMENT IN RADIOLOGICAL THREAT AND EMERGENCY P. Smolander, S. Kuukankorpi, M. Moring, H. Toivonen STUK - Radiation and Nuclear Safety Authority. In addition to in-field measurements and analyses, fast communication means and related data management are needed for a successful response to a radiological threat. For gamma spectrometric measurements, a database LINSSI has been developed by the Finnish Radiation and Nuclear Safety Authority (STUK) and its partners. LINSSI supports multiple measurements and analyses of the same sample, mobile applications, and above all, transfer of the observations from one database to another. For emergency response, STUK has developed a vehicle SONNI which has powerful tools to locate and identify radiation sources. In August 2005, SONNI was used in the Helsinki Athletics World Championship games for securing the safety of the athletes and the public. Using three NaI(Tl) detectors and one HPGe detector 108,000 gamma spectra were acquired in intervals of five seconds. All measurement and analysis data were stored in the LINSSI database. Presence of certain radionuclides, such as Co-60, Cs-137 and Ir-192, was analyzed in real time using H0-hyphothesis test for spectral data in the LINSSI database. If peak significance exceeded a preset threshold, a short data message was automatically generated and transferred to the Operations Centre via a secure mobile communication link (Tetra network). MODELING β-γ COINCIDENCE SPECTRA OF 131MXE, 133XE, 133MXE, AND 135XE SIGNALS D. A. Haas, S. R. Biegalski, K. M. Foltz Biegalski. To support the 213 214 51 development of β-γ coincidence spectroscopy for radioxenon monitoring, tools have been developed to calculate the spectra produced by these systems. Detailed MCNPX models have been developed to calculate the detector response for all the electrons and photons emitted from 131mXe, 133Xe, 133mXe, and 135Xe signals. A MatLab code was written to incorporate the MCNPX results in the calculation of coincidence spectra. The computed spectra are being utilized to aid in the development of the Spectral Deconvolution Analysis Tool (SDAT) and to calibrate β-γ coincidence systems. The models developed for this work include improvements over previous models in their ability to address Compton scattering for 135Xe, the beta distribution offset in the 30 keV region for 133Xe, and the correct spike at low energies in the 133Xe beta distributions. 215 AUTOMATED ANALYTICAL SEPARATIONS FOR THE THERMAL IONIZATION MASS SPECTROMETER (TIMS) James Sommers, Dan Cummings, Mike Michlik and Jeffrey Giglio. A novel, cost effective and efficient means of performing chemical separations for analysis of radiological samples via thermal ionization mass spectrometry (TIMS) has been developed. Employing an automated gas pressurized extraction chromatography (GPEC) system, an analytical chemistry method will be discussed and compared to traditional gravity fed separations for TIMS analysis. Factors for comparison will include cost of materials, time of separations, recoveries of separations, among other experimental considerations. In addition to the analytical figures of merit, the controlling software written in Labview will also be discussed. MEASUREMENT OF BURN-UP MONITORS BY INDUCTIVELY COUPLED PLASMA MASS SPECTROMETRY (ICP-MS) Daniel Cummings, James Sommers and Jeffrey Giglio. The development of modern analytical chemistry instrumentation has opened many new avenues of research and development in the nuclear industry. One of the most dramatic enhancements of measurement capabilities has been the ICP-MS. The fission product historically used to determine burn-up has been Nd-148. This wet chemistry method is time consuming and has very low through-put of samples, among other disadvantages. The use of ICP-MS allows for the determination of a wide variety of fission products accurately and precisely. For example, the determination of Tc, La, Pr, and Ce can all be determined in a singe analysis, in the same dilution (due to similar fission product yields). The determination of Nd-148 by ICP-MS requires a chemical separation to remove the isobaric interferences from other rare earth elements. This presentation will discuss the comparison of burn-up calculation based on the determination of the fission products Tc, La, Pr, and Ce by ICP-MS vs. the historical Nd-148 also determined by ICP-MS but with a chromatographic isolation of the Nd. The results will be compared and conclusions drawn on the applicability of using alternative fission product analytes vs. the historical Nd-148. 216 52 217 "AGE" DATING OF A COBALT SOURCE BY INDUCTIVELY COUPLED PLASMA MASS SPECTROMETRY Jeffrey Gigio, Daniel Cummings, James Sommers, Mary Adamic and Kevin Carney. The "age" dating of a sealed cobalt-60 source by inductively coupled plasma mass spectrometry (ICP-MS) will be discussed. The paper will demonstrate the successful dismantling, and dissolution of the Co-60 source in a hot cell environment. Additionally, a means of separating the parent/daughter analytes (Co-60/Ni-60) via a gas pressurized extraction chromatography system prior to analysis will be discussed. The results of an investigation into using a second parent/daughter relationship (Ni-63/Cu-63) and its difficulties will be presented. Lastly, details of the analysis of the separated Co and Ni fractions by ICP-MS will be discussed. The analytical figures of merit, along with the accuracy and precision of the analytical method will be presented. The experimental results will be compared to the "true" age of the Co source. ON BARIUM ANOMALIES IN CONTEXT WITH VOLCANIC ACTIVITIES IN THE AEGEAN Georg Steinhauser, Johannes H. Sterba, Max Bichler (Atominstitut of the Austrian Universities), Robert Seemann (Museum of Natural History Vienna). Recent studies raised the question of the correlation of barium concentration anomalies in sedimentary sequences to volcanic activity. We observed a certain coincidence of increased Ba values in such samples and volcanic events. Especially cave sediments from the Charkadio Cave on the island of Tilos (Dodekanes, Greece) offered some insight in this respect. This island is mostly composed of karstified limestone and therefore not of volcanic origin but neighbored to several volcanoes of the south-eastern Aegean Sea (Kos, Nisyros, and Giali). Sampling the fine grained, fossil rich (dwarf elephants) sediments of Charkadio Cave, it is possible to look back into the youngest geological history of this area. Some of these layers contain volcanic particles (ash grains, pumice lapilli). Interestingly, these layers have the highest content of Ba, analyzed using neutron activation analysis. Additionally to this discovery, hedgehog-like idiomorphic baryte crystals were found in some of these layers. Thus, Ba must exist on the surface of tephra particles in volatile and water-soluble compounds. Since cave sediments from another cave on Tilos, which was recently opened and definitely not exposed to volcanic products, contains significantly less Ba, we conclude that a mobile Ba compound is contributed to the sediments by volcanic fallout. TAKING A SIP FROM A VOLCANIC COCKTAIL Johannes H. Sterba, Georg Steinhauser, Max Bichler; Atominstitut of the Austrian Universities, Vienna University of Technology. The search for the telltale signs of volcanic eruptions in easily dateable (biological) material like tree rings or speleothems has been going on for a very long time. Even 218 219 53 though the reactions of tree rings to cataclysmic events are fairly well understood, there has not been a satisfactory method to distinguish volcanic from other climatically active events. Recent findings of differing Bacontents in soil and the unexpected mobility of Ba during volcanic eruptions strongly suggest that tephra changes the concentrations of trace elements in the topsoil. To better understand the mechanics of this enrichment, leaching experiments with volcanic ashes have been performed. NAA with its reasonably simple sample preparation and the possibility to distinguish volcanic ashes from contamination of solvents by using activated ashes offers a hands on approach to the problem above. Several samples of known composition of volcanic ashes have been activated and leached with different solvents and solutions, aiming to both recreate a realistic situation comparable to natural leaching due to rain fall and obtain quantifiable results. 220 Trends in Nuclear Education Lartigue J. , Martinez T. , Faculty of Chemistry, National University of Mexico.. Today‘s nuclear curricula have the purpose to fulfil the manpower requirements of the nuclear world market, both in the power and the applications branches, keeping up the high academic level required by the Nuclear Science research and the development and operation of the Nuclear Technology. This work analyses the nuclear market and the present situation of nuclear education in several countries, including Mexico and the US, as well as the collective efforts promoted by the IAEA and other organisations. Some conclusions are obtained about the present status and future trends in nuclear education, particularly in the Nuclear and Radiochemistry area. OCEANIC 137CS: IMPROVEMENT OF 137CS ANALYSIS IN SMALL VOLUMEB SEAWATER SAMPLES USING THE UNDERGROUND FACILITY (OGOYA) K. Hirose1, M. Aoyama1, Y. Igarashi1 and K. Komura2 1. Geochemical Research Department, Meteorological Research Institute, Nagamine 1-1, Ibaraki 305-0052, Japan 2. Low Level Radioactivity Laboratory, Kanazawa University, Wake, Tatsunokuchi, Ishikawa 923-1224, Japan. 137Cs in the environment, a major fission product with a long physical half-life of 30 years, has been mainly derived from global fallout. 137Cs in the ocean is one of chemical tracers of water mass motion at the time scale of several decades because most of the 137Cs in water columns is present as a dissolved form. In order to achieve the comprehensive oceanographic use of 137Cs as a tracer, more sensitive and convenient techniques of 137Cs measurements have been required. As a result of improvement of the 137Cs adsorption technique from seawater using ammonium phosphomolybdate (AMP) and use of extremely low background gamma-spectrometry in the underground laboratory (Ogoya), we have succeeded the 137Cs determination in seawater with a smaller sample volume of around 10 L for shallow waters (< 1000 m). However, sensitivity of 137Cs determination is not enough for deep waters 221 54 because of interference due to the presence of trace amount of 40K in AMP precipitation. In order to remove 40K in AMP precipitation, we added a purification process of 137Cs using hexachloroplatinic acid. The result revealed that interference of 40K disappears in gamma-spectrum. The most sensitive measurement of 137Cs is achieved using gamma-spectrometry. The improved method can be applied to determine 137Cs in small samples (less than 10 L) of deep waters of the South Pacific. 222 Prompt Gamma Activation Analysis of samples in thick containers Zsolt Révay, Tamás Belgya, László Szentmiklósi, Institue of Isotopes. Thanks to the deep penetration of both neutrons and gamma radiation, prompt gamma activation analysis (PGAA) provides the average composition over the irradiated volume of the sample. This makes possible the analysis of samples in relatively thick-walled containers. During the routine analysis, targets are packed in Teflon bags or vials. Quartz vials are also used for the irradiation of liquid samples. In these cases the elemental components of the transparent packing material can easily be accounted for, similarly to those of any inhomogeneous samples. Since both the neutron beam and the detected gamma radiation are collimated, a well-defined active volume of the bulk sample is analyzed. Using a proper geometry, the container can be made practically invisible. Using this ―invisible container method‖, many low cross-section materials can be measured with PGAA, even when they are stored in higher cross-section containers, e.g. noble gases in aluminum cans. However, in many practical cases, gammas from the packing material cannot be eliminated from the spectrum. In these cases packaged materials can still be detected if they have higher cross-section, higher energy lines, or different half-life radioactive products than the container components. A technique was developed at our department for the detection of fissile material hidden in radiation shielding containers. Calculations and model experiments were performed to demonstrate that high-energy prompt gamma lines can be used for analysis, even when they are emitted inside a thick shielding. Measurements were made using natural and highly-enriched uranium in different containers. Low-mass fissile materials proved to produce a strong and characteristic gamma-radiation, even when irradiated in massive lead and iron containers. The isotopic compositions and also the concentrations of higher cross-section elements (e.g. H in uranile acetate) were determined reproducibly inside the containers. Fissile materials are detectable in this way also in the presence of masking radioactive sources. Compendium of Gamma-ray Spectrum of Rare Radionuclides Lennox Harris, Reginald Gaylord, Norris Harward, David Wruck, Michael West, Mark Mitchell, Leonard Gray and Brian Anderson. Abstract:Recently, the Heavy Element Facility, formerly a Category II nuclear facility at Lawrence Livermore National Laboratory achieved Radiological Status per DOE-STD-1027-92. Historically the Heavy Element Facility supported 223 55 nuclear testing and performed actinide research that included the transplutonium elements. Among the isotopes used were a wide variety of high specific activity - Alpha emitters such as 241Am, 243Cm, 252Cf, 233U, 238,239Pu. Other research included studies with 247Bk, 252Es, 242mAm, 166Er, 166mHo, 242Pu, and 178Hf. Following the end of the cold war, the Heavy Element Facility lost its mission as nuclear testing ceased. For a short time the facility was in standby mode, storing various quantities of highly radioactive products. To reduce and ultimately eliminate the risk associated with a Category II nuclear facility, the Building 251 Risk Reduction Program was initiated by the Environmental Protection Department. One of the goals of the Risk Reduction Program was to accurately characterize the nuclear inventory for release and relocation to other Department Of Energy complex facilities or commercial facilities or package for disposition as waste. The characterization process included confirmatory measurements and identification of the nuclear materials inventory, review of databases, and historical process knowledge, physical inspection, x-ray radiography, alpha swipe sampling, and finally gamma ray analysis. To accomplish the latter task conventional gamma ray spectroscopy was employed using a High Purity Germanium detector counting system with commercial off-the-shelf software. Greater than 1600 gamma ray spectrum were analyzed to determine isotopics and quantity of activity needed for characterization for determining disposition as defined by G430.1-5 IGD requirements for Hazardous waste acceptance criteria. This paper highlights some of the gamma spectrum of rarely seen radionuclides and demonstrates gamma ray analysis and identification using parent daughter relationships of otherwise esoteric radionuclides. Terms: Rare Radionuclide – Unusual radionuclides with some peculiarities. Isotopes - Element whose nuclei have the same atomic number, (same number of protons), different atomic masses (different numbers of neutrons). 224 ESTABLISHMENT OF A RADIOCHEMISTRY PROGRAM AT SOUTH CAROLINA STATE UNIVERSITY R. Craig Williamson, Director, South Carolina Universities Research and Education Foundation. The South Carolina State University through the sponsorship of the National Nuclear Security Administration has developed a radiochemistry program, which utilizes the combined resources and talents of an existing radiochemistry program at Clemson University, and the staff and program activities at the Savannah River National Laboratory. The overall goal of the program is to assist the U. S. Department of Energy (DOE) in increasing the pool of radiochemists that are U. S. citizens and to augment the nation's security by developing an educational and research program in radiochemistry for the education and training of radiochemists to analyze and study radiological samples. The specific objectives for accomplishing the goal are: (1) to recruit and train highly talented African Americans, Hispanic Americans, and Native Americans in the area of radiochemistry and related fields across the nation; (2) to assist the nation in 56 preparing first responders to nuclear emergencies such as radiological dispersion devices; (3) to provide internships for twelve students (six per year for two years) in radiochemistry, health physics, and nuclear engineering students; (4) to enhance the Applied Radiation Sciences Laboratory at SCSU to perform cutting edge instruction and research in radiochemistry; (5) to promote and encourage students to seek an education in radiochemistry. The SCSU in radiochemistry has drawn on the successes of the SCSU/UW/SRNL partnership in nuclear engineering. To accomplish this, SCSU is in the process of hiring a radiochemistry professor, develop a concentration in radiochemistry through its chemistry and nuclear engineering programs, and expand its new Applied Radiation Sciences Laboratory (ARSL) capability to include additional instrumentation necessary to radiochemistry instruction and research. SCSU has expanded its new Applied Radiation Sciences Laboratory (ARSL) facility capability to include additional instrumentation necessary to radiochemistry instruction and applications, e.g. a liquid scintillation counter and a high purity geranium detector. Three laboratory-based radiochemistry courses are being developed for the radiochemistry concentration. This laboratory work has been designed to meet the nation's need for security from terrorism as well as for general readiness. 225 RADIOCHEMISTRY EDUCATION AWARD PROGRAM John Gutteridge, U. S. Department of Energy. The Radiochemistry Education Award Program (REAP) was initiated by DOE-NE in 1999 to stimulate the education and training of scientists and engineers with expertise in radiochemistry. Workforce studies have shown that there is increasing demand for radiochemists due, in part, to the retirement of senior expertise developed in the early days of nuclear programs, which is occurring at the same time that radiochemistry graduation rates are declining rapidly. To address this concern, the DOE initiated REAP-I which, through a competitive process, funded three universities (Clemson University, University of Missouri-Columbia and Washington State University) for three years. Due to the success of REAP-I, a second program (REAP-II) was initiated in 2002. In the second program, Colorado State University, the University of Texas at Austin, Clemson University, and Washington State University received support with similar goals to the initial program. And, as of last year REAP III began with funds going to Clemson, Washington State, Texas and, a new program, at Penn State University. Overall, as a result of the REAP program, new faculty have been added, laboratories refurbished and upgraded with new instrumentation, the number of graduate students with a focus on radiochemistry has increased substantially, new linkages have been established with DOE facilities including internships for students and new research programs funded. The REAP program is having the desired affect of increasing the number of faculty and graduate students in radiochemistry with the end result of more graduates being generated to address the needs of DOE and the nuclear community. (Craig can we make 57 the point explicitly that the DOE REAP funds have led to major contributions to Radiochemistry on the part of the university, labs, private sector, etc. and that the major improvements and advances at these universities in their Radiochemistry program could never have been achieved with just the DOE/NE funding but this funding was critical in helping to reestablish or establish, whatever the case may be, new vivacity in the R/C curriculum and that much of the progress to date has come because of the additional or leveraged funds that the DOE funding made possible. 226 MINERAL CONTENT OF MEDICINAL PLANTS USED IN URINARY TRACT INFECTIONS Zohra Lamari, Commena Nuclear Research Center of Draria, Algiers, Algeria, Sheldon Landsberger, Nuclear Engineering Teaching Lab, University of Texas, Austin, Texas, Jon Braisted,Nuclear Engineering Teaching Lab, University of Texas, Austin. The kidney is the predominant organ of the urinary tract and it plays a significant role in the regulation of total body homeostasis. The frequency of the administration of some drugs, antibiotics as well as excess consumption of calcium, analgesics, and anesthetics, have been shown to produce damage of the kidney resulting in consequences like urinary tract infections. This disease can be treated with medicinal herbs which are widespread in Algeria. In this study work was undertaken to analyze elemental composition in nine medicinal plants: Androgena citratus, Punica Granatum, Glyryrrhiza Glabra, Lausaunia Alba, Ceratonia Siliquata, Fragaria Vesca, Arbutus Unedol, Hordeum Vulgare, and Papietaria Officinalis used to cure urinary tract infections. We used short, medium and long lived NAA in conjunction with epithermal irradiations and Compton suppression to determine many trace concentrations. This database may be of important significance in understanding the therapeutic aspects of medicinal plants. IMMOBILIZATION OF FISSION IODINE BY REACTION WITH INSOLUBLE NATURAL ORGANIC MATTER Gregory T. Schmett1, Spencer M. Steinberg1, Ginger M. Kimble1, David W. Emerson1, Vernon Hodge1, Mark Rudin2, Mary Turner2, 1Department of Chemistry, University of Nevada Las Vegas, Las Vegas, NV 89154, 2Department of Heath Physics, University of Nevada Las Vegas, Las Vegas, NV 89154. Iodine-129 (129I) is a fission by-product and is highly mobile in the environment. Iodine-129, along with other stable isotopes of iodine, is released during the reprocessing of nuclear fuel and must be trapped to prevent the release of radioactivity to the environment. Past studies have provided evidence that iodine can become associated with Natural Organic Matter (NOM). This research explores the use of NOM (sphagnum peat) to sequester iodine from the vapor and aqueous phases. NOM-associated iodine may be stable for geological storage. NOM-sequestered iodine can be recovered by pyrolysis to prepare target materials for transmutation. The nature of the NOM-iodine association has been explored and compared to 227 58 activated carbon. 228 ABIOTIC REACTION OF IODINE AND IODATE WITH SPHAGNUM PEAT Spencer M. Steinberg1, Ginger M. Kimble1, Gregory T. Schmett1, David W. Emerson1, Vernon Hodge1, Mark Rudin2, Mary Turner2, 1Department of Chemistry, University of Nevada Las Vegas, Las Vegas, NV 89154, 2Department of Heath Physics, University of Nevada Las Vegas, Las Vegas, NV 89154. Previous studies have shown that iodine (including 129I) can be strongly retained in organic-rich surface soils and sediment and that a large fraction of soluble iodine may be associated with dissolved humic material. Iodate reacts with Natural Organic Matter (NOM) and undergoes an abiotic pseudo first-order reaction leading to either reduction of IOH or I2. This intermediate is subsequently incorporated into the organic matter. Using model compounds, we have inferred that iodine reacts with peat by aromatic substitution of hydrogen on phenolic constituents of the peat. Alternatively, the intermediate, IOH or I2, may be reduced to iodide. The pH (and temperature) dependence of the iodate reaction (reduction) has been explored with sphagnum peat, humic acid, and several model compounds. The incorporation of iodine into NOM has been verified by pyrolysis gas chromatography/mass spectrometry (GC/MS). Model compound studies indicate that reduction of iodate to IOH may result from reaction with hydroquinone (or semiquinone) moieties of the peat. NEUTRON DEPTH PROFILING COLLABORATION BETWEEN THE UNIVERSITY OF TEXAS AT AUSTIN AND NIST S. M. Whitney (The University of Texas at Austin), S. R. Biegalski (The University of Texas at Austin), R. G. Downing (NIST). The University of Texas at Austin and the National Institute of Standards and Technology (NIST) have collaborated in the analyses of silicate materials doped with boron in order to determine the concentration versus depth profile of the dopant atoms. The University of Texas at Austin has recently assembled an operational neutron depth profiling (NDP) facility and has worked to improve the facility with the assistance of technology and experience shared from the NIST NDP facility. The NDP technique utilizes neutron absorption reactions with light-element dopants to non-destructively determine profiles of the dopant concentration related to its depth in the matrix material. The technique relies on the energy attenuation of alpha and lithium recoil particles and measurement of the residual energy as they exit the sample. Two specific samples were measured at NIST as well as at the University of Texas at Austin. The first sample consisted of multiple layers of phosphosilicate glass followed by borosilicate glass. The second sample was a very thin borosilicate glass deposited on a silicon wafer. The resulting profiles determined by each facility were compared to intercalibrate the instruments at the two facilities as well as evaluate the accuracy of each facility's analysis routine. 229 59 230 MEASUREMENTS OF PLUTONIUM ACTIVITY CONCENTRATIONS AND 240Pu/239Pu ATOM RATIOS IN BROWN ALGAE (FUCUS DISTICHUS) COLLECTED FROM THE LITTORAL ZONE OF AMCHITKA ISLAND USING ACCELERATOR MASS SPECTROMETRY (AMS). Terry Hamilton, Doug Dasher, Tom Brown, Alfredo Marchetti, Roger Martinelli, and Steven Kehl Lawrence Livermore National Laboratory . Plutonium-239 (239Pu) and plutonium-240 (240Pu) activity concentrations and 240Pu/239Pu atom ratios are reported for Brown Algae (Fucus distichus) collected from the littoral zone of Amchitka Island (Alaska) and at a control site on the Alaskan peninsula. Plutonium isotope measurements were performed in replicate using Accelerator Mass Spectrometry (AMS). The average 240Pu/239Pu atom ratio observed in dried Fucus d. collected from Amchitka Island was 0.227 ± 0.007 (n=5) and compares with the expected 240Pu/239Pu atom ratio in integrated worldwide fallout deposition in the Northern Hemisphere of 0.1805 ± 0.0057. In general, the characteristically high 240Pu/239Pu content of Fucus d. analyzed in this study appear to indicate the presence of a discernible basin-wide secondary source of plutonium entering the marine environment and is not necessarily linked to the underground nuclear test program on Amchitka Island (196571). Work performed under the auspices of the U.S. Department of Energy by the University of California, Lawrence Livermore National Laboratory under Contract No. W-7405-Eng-48. 231 PRECONCENTRATION OF CESIUM-137 (137CS) FROM LARGE VOLUME WATER SAMPLES USING ZIRCONIUM FERROCYANIDE EMBEDDED ON CARTRIDGE WATER FILTERS. Terry Hamilton, Roger Martinelli, Steven Kehl and Jim Brunk.. The determination of cesium-137 (137Cs) in surface waters usually requires some form of preconcentration prior to radiometric analysis. There are many types of inorganic sorbents suitable for this application including ammonium molybdophosphates (AMP), natural and synthetic zeolites, and ferrocyanides of transition metals. Ferrocyanides are relatively easy to prepare and generally provide high selectivity for separation of cesium in the presence of alkaline and alkali metals. This paper describes a method for preparing a zirconium ferrocyanide (ZrFeCN) based sorbent material that is conveniently embedded on a polyethylene wound water filter cartridge (0.5 mm MicroWynd®, Cuno Inc.). These ZrFeCN based sorbent cartridges have been used extensively at former nuclear test sites in the Marshall Islands for preconcentration of 137Cs in water samples collected on plate lysimeters. At 60 pump rates of < 2 liters per minute, the ZrFeCN cartridge collections exhibit a very high efficiency for cesium uptake (>95%) and good stability for longterm, automated field applications. The use of a synthetic support base (in this case, polyethylene) for the sorbent was preferred over more commonly used natural cotton materials because of its lower 137Cs background and ash content. 232 Non-Carbon Based Compact Shadow Shielding of 14 MeV Neutrons Lucian Wielopolski, Sudeep Mitra with Brookhaven National Laboratory; Oded Doron, University of Texas at Austin. A system based on inelastic neutron scattering is being constructed for non-destructive monitoring of carbon in soil. For that purpose, 14 MeV fast neutrons emanating isotropically from a d,t neutron generator (NG) interact with carbon nuclei in the soil inducing 4.4 MeV gamma rays. The induced gamma radiation is counted by an array of three NaI(Tl) detectors. To reduce the direct radiation from the NG from reaching the detection system, a shadow shielding is introduced between them. However, the common materials used for thermalizing and capturing fast neutrons are borated plastics that contain carbon, the element of interest. Thus in addition to weight constrains due to required mobility of the system, the shielding should be free of carbon. The current shielding consists of iron, borated water, boric acid, and cerrabend, a low melting point alloy (Bi 50%, Pb 26.70%, Sn 13.3%, and Cd 10%). The shielding has been found to be effective in eliminating neutrons below 0.5 eV. However, neutrons with higher energies penetrate the shielding and reach the detectors. Further optimization of the shielding assembly will be completed utilizing MCNP5 and field experiments and will be presented. Advantages of MESH tallying in MCNP5 for Soil Analysis Calculations Oded Doron, University of Texas at Austin; and Lucian Wielopolski, Brookhaven National Laboratory. The Monte Carlo code, MCNP5, includes a new mesh tally option useful for large matrix calculations. The mesh tally is a virtual grid structure superimposed on a geometry rather than being defined as part of the geometry. In the mesh tally, the track length estimate of the particle flux is calculated and the flux is distributed to the defined mesh cells utilizing an efficient algorithm. As a result, the mesh tally allows for the calculation of large matrices with greatly reduced computer runtimes. In the lattice flux tally in MCNP, the flux is calculated separately for every tallying cell, which for a large matrix can become computationally cumbersome. Recently, a fast lattice tally (FLT) has been developed for MCNPX. Although FLT offers competitive computational times, it is not applicable for all lattice cases. MCNP5 was utilized to model an inelastic neutron scattering in-situ soil analysis system. The tallies were used to calculate the reaction rates of fast neutron interactions with carbon via inelastic reactions. The calculations were carried out in a soil volume of 250cm by 200cm by 50cm deep containing 2.5 million 1 cm3 voxels. The results of these three tallies and their respective computational times are 233 61 compared, and the advantages are discussed. 234 The Time and Depth Dependent Fluxes Due To 14 MeV Neutrons Impinging Soil S. Biegalski (The University of Texas at Austin), L. Wielopolski (Brookhaven National Laboratory), O. Doron (The University of Texas at Austin). A spectroscopy system measuring inelastic neutron scattering and thermal neutron capture induced gamma rays is being developed for in-situ soil analysis. Since a pulsed fast D-T neutron source is utilized, fast neutron induced inelastic neutron scattering reactions are separated in time from thermal neutron capture events. Models utilizing the MCNP code have been developed to study the time and energy variations of the neutrons in the soil matrix. This information will be utilized for calculating the reaction rates and optimization of the gating of gamma-ray spectral acquisition times. This information is also required to determine the sampled volume in the soil and should assist in deconvolving the time-dependent gamma-ray signature measured by the NaI detectors. In our preliminary results we observed that after 106 shakes (0.01 s) virtually all the neutrons have either escaped the system, defined as a soil volume of 200 cm2 by 50 cm deep, or have been absorbed. Results will be presented indicating the time and energy dependent reaction rates and gamma yields at specific depths and lateral distances for Si, C, O, N, S, and P, demonstrating the effect of the variations in the neutron energies on the gamma yields. THE ASSESSMENT OF INDOOR AIR QUALITY WITH RESPECT TO 222Rn IN BUILDINGS CONSTRUCTED ON DISUSED TINMINING AREAS A. M. Yusof and W. M. Chow. 1Department of Chemistry, Faculty of Science, Universiti Teknologi Malaysia, 81310 UTM Skudai, Malaysia. The cassiterite minerals containing tin are rich in thorium and uranium found in the xenotime and monazite minerals commonly present in the Malaysian terrains. With the upheaval of these minerals from tin-mining activities, for secondary landuses development, the environment is basically exposed to the natural radioactive materials derived from the 232Th and 238U radionuclides. One of the daughter products is 222Rn and it is known to be one of the major, indoor air pollutants related to the sick-building syndrome. High concentrations of indoor 222Rn will be hazardous to human health which is often associated to lung cancer and other chronic diseases. The main purpose of this study is to determine the concentrations of indoor 222Rn in residential areas constructed on former tin-mining areas with particular reference to places with high human activities such as commercial areas. Air samples were collected using the RDX-013 scintillator cell and the quantity of 222Rn determined by the RDA-200 radon/thoron detector. Measurements were made at different times and intervals for the purpose of looking at variations in 222Rn levels present in the buildings. Results of this study showed that the concentration of indoor 222Rn is higher in the 235 62 morning (1.64±0.20 pCi.L-1) compared to the levels detected in the afternoon (1.30±0.08 pCi.L-1) for most residential areas. As expected the concentration of 222Rn outdoor is lower (1.08±0.08 pCi.L-1) compared to the concentration determined indoor (1.64±0.20 pCi.L-1). Recently constructed houses or buildings in commercial centers seemed to have 222Rn concentrations relatively higher than those occupied for longer periods of time. However the levels of 222Rn concentrations in the study area showed that all were below the maximum permissible level of 4.0 pCi.L-1 as stipulated by the United States Environmental Protection Agency (USEPA). This work also discussed the mitigation measures taken by the building management of commercial buildings to reduce the risk of 222Rn build-up in an effort to improve public health due to poor indoor air quality. 236 DISPERSION OF HYDRATED IRON(III) OXIDE ONTO ACID ACTIVATED CARBON FOR THE REMOVAL OF Cr(VI), As(III) AND As(V) IN DRINKING WATER A. M. Yusof and M. Adil. Department of Chemistry, Faculty of Science, Universiti Teknologi Malaysia, 81310 UTM Skudai, Malaysia. In this work, prepared acid activated carbons were modified through dispersion of hydrated iron(III) oxide (HFO) onto the porous surfaces of carbon. Acid activation makes the carbon suitable for metal uptake. Thus, Fe(III) was loaded onto the acid activated carbon. Then loaded Fe(III) was converted into HFO using alkali and thermal treatment. Due to higher pHZPC, HFO, unlike acid activated carbon, exposes positively charged sites suitable for removing some anions. Prepared acid activated and modified carbons were characterized for their porous structure and Fe content using N2 adsorptiondesorption and scanning electron microscopy, and EDX techniques respectively. Modification destroys the micro-pores tremendously in the parent carbon whereas the reduced level of meso-pores and macro-pores are comparable with that of a commercial one. The dispersion of HFO is speculated from the higher level of Fe(III) content and from the deposition of agglomerated HFO in the submicron scale inside pores. The suitability of the modified carbon for the removal of anions/non-ionic species were testified using Cr(VI), As(V), and As(III) as adsorbate. Cr(VI) was determined with UV-Vis spectroscopy while As(III) and As(V) with ICP-MS. Parent activated carbons were found far better than the modified ones in removing Cr(VI). The modified one was found to be better in removing As(V) and As(III) (1.0-1.5 mg.g-1). PREPARATION OF PURE SILICA OXIDE (SiO2) AND ZEOLITE Y FROM RICE HUSK AS AN ION EXCHANGER A. M. Yusof1 and M. M. Rahman2. 1Department of Chemistry, Faculty of Science, Universiti Teknologi Malaysia, 81310 UTM Skudai, Malaysia. 2Department of Chemistry, Faculty of Science and Technology, KUSTEM, Mengabang Telipot, 21030 Kuala Terengganu, Malaysia. In this work, prepared acid activated carbons were modified through dispersion of 237 63 hydrated iron(III) oxide (HFO) onto the porous surfaces of carbon. Acid activation makes the carbon suitable for metal uptake. Thus, Fe(III) was loaded onto the acid activated carbon. Then loaded Fe(III) was converted into HFO using alkali and thermal treatment. Due to higher pHZPC, HFO, unlike acid activated carbon, exposes positively charged sites suitable for removing some anions. Prepared acid activated and modified carbons were characterized for their porous structure and Fe content using N2 adsorptiondesorption and scanning electron microscopy, and EDX techniques respectively. Modification destroys the micro-pores tremendously in the parent carbon whereas the reduced level of meso-pores and macro-pores are comparable with that of a commercial one. The dispersion of HFO is speculated from the higher level of Fe(III) content and from the deposition of agglomerated HFO in the submicron scale inside pores. The suitability of the modified carbon for the removal of anions/non-ionic species were testified using Cr(VI), As(V), and As(III) as adsorbate. Cr(VI) was determined with UV-Vis spectroscopy while As(III) and As(V) with ICP-MS. Parent activated carbons were found far better than the modified ones in removing Cr(VI). The modified one was found to be better in removing As(V) and As(III) (1.0-1.5 mg.g-1). 238 A HIGH-SENSITIVITY LARGE VOLUME CRYOGENIC DETECTOR FOR RADON IN GAS M. Wojcik, Jagellonian University, Institute of Physics, Reymonta 4, PL-30059 Krakow, G. Zuzel, Max Planck Institute for Nuclear Physics, Saupfercheckweg 1, D-69117 Heidelberg. A new detector for 222Rn measurements in gases is described. It is based on the low-temperature collection of radon on a stainless steel plate and the following counting of emitted alpha particles using a standard semiconductor detector for alpha spectroscopy. A very low background of the system was achieved, in the order of 25 counts per day for the 222Rn energy window. Relatively high detection efficiency of 31 % in 2π geometry, and large volume of the detector allow radon concentration measurements at the level of 14 mBq/m3 with a 30 % accuracy. Behavior of short-lived radon daughters, 218Po and 214Po, is also analyzed. 239 U-234/U-235 ACTIVITY RATIOS AS A PROBE FOR THE U-238/U235 HALF-LIFE RATIO S. Pommé 1, E. García-Toraño 2, G. Sibbens 1. 1) EC-JRC-IRMM, Institute for Reference Materials and Measurements, Retieseweg 111, B-2440 Geel, Belgium, 2) Laboratorio de Metrología de Radiaciones Ionizantes, CIEMAT, Madrid, Spain.. The uranium isotopes U-235 and U-238, because of their long half-lives, have important applications, in particular for nuclear geochronology. The most accurate measurements, by Jaffey et al., have up to now not been confirmed by other measurements of comparable accuracy. Hence, the validity of dating via the uranium-lead system is predominantly 64 dependent on this single experiment. In this work, we supply some additional experimental information on the U235 and U-238 half-lives. High resolution alpha spectrometry was performed on three enriched U-235 materials, containing also impurity traces of U-234. Assuming the U-234 in the material to be in equilibrium with its parent, U-238, it can be used as a probe for the half-life of the latter. Relying on the isotopic composition of the uranium, as determined by mass spectrometry techniques, the ratio of halflives of U-238 and U-235 was determined via the activity ratio of U-234 and U-235. Preliminary results on one material confirm the half-life ratio within a few tenths of percent. Yet, a discrepancy was detected with another material, which raises questions about the attainable accuracy with mass spectrometry on ultra-low amounts of U-234. 240 INTERNATIONAL MEASUREMENT COMPARISON OF 137CS, 40K AND 90SR IN MILK POWDER Y. Spasova, U. Wätjen, T. Altzitzoglou; EC - JRC Institute for Reference Materials and Measurements. Recently, IRMM has assumed responsibility for organising regular measurement comparisons among those laboratories which provide radioactivity monitoring data from their country to authorities of the European Commission (EC) under various EC legislation articles, e.g. Article 35 and 36 of the EURATOM Treaty. The principal objective of such intercomparisons is to give the opportunity to individual laboratories for checking their procedures of measurement, demonstrating their capability to measure correct values of radioactivity in the environment and food stuff at levels corresponding to routine situations. The most recent exercise under this International Comparison Scheme for Radioactivity Environmental Monitoring (ICS-REM) is presented here. More than 130 units of milk powder were distributed to 62 laboratories in all Member States and Candidate Countries of the European Union. Participating laboratories were mainly national competent authorities and research institutes. The exercise was designed to evaluate the performance of the participating laboratories in measuring 137Cs, 40K and the pure beta-decaying 90Sr activity in this material. The whole cycle of the intercomparison is described, including the establishment of traceable reference values, demonstration of the homogeneity of the distributed samples, treatment and measurement of samples in the participating laboratories, and evaluation of the results. DETERMINATION OF TRACE ELEMENTS IN SCALP HAIR OF AN ELDERLY POPULATION BY NEUTRON ACTIVATION ANALYSIS M. Saiki (1); O. Jaluul (2); N. M. Sumita(2); W. Jacob-Filho(2) - (1)Instituto de Pesquisas Energéticas e Nucleares (2) Faculdade de Medicina, São Paulo University. During the past three decades the investigation of trace element concentrations in human scalp hair has become increasingly popular for biomonitoring environmental exposure, evaluating systematic intoxication, assessing nutritional status and diagnosing diseases. Although hair is the 241 65 most convenient tissue for trace element determinations there is also considerable controversy of using hair to evaluate nutritional status and clinical symptoms. In the present study instrumental neutron activation analysis was applied for element determinations in scalp hair samples from a healthy elderly population of São Paulo city, to further establish element concentration reference or normal ranges values for this group. The hair samples were collected from 43 individuals aged 50-80 years and living in the São Paulo Metropolitan region. The hair samples were washed four times with each of the following solutions: Triton X100, acetone and purified water. Concentrations of the elements As, Br, Ca, Cl, Cr, Cu, Fe, K, La, Mn, Na, Sb, Se and Zn were determined using short and long irradiations at the IEA-R1 research nuclear reactor. The induced gamma activities of the samples and standards were measured using a gamma-ray spectrometer.The result indicated a difficulty to define reference ranges due to wide concentration variations between the individuals due to natural hair composition probably as a result factors such as age, hair color, dietary habits, sex and, geographical origins. Comparisons made between the results indicated that most of the elements determined are within the previous data obtained from a control group aged 21-45 years. The method was tested by the analysis of reference materials and the results showed agreement with the reference values. Acknowledgments: To FAPESP and CNPq for the financial support. 242 INAA OF ENAMEL AND DENTINE SAMPLES SAMPLES OF A GROUP OF CHILDREN AND ADULTS: A COMPARTIVE STUDY Marco A. B. Soares, Eduardo M. Adachi, M. Saiki - Instituto de Pesquisas Energéticas e Nucleares- IPEN-CNEN/SP. Determinations of trace element in dental tissues have been carried out for several purposes such as in the investigations of dental caries, for monitoring exposure to toxic elements, anthropological studies and to detect nutritional deficiencies. Most analyses of teeth are made using entire tooth. In present study, however, tooth tissues were separately and enamel and dentine were analyzed individually. Tooth samples of a group of 10 children and 10 adults were acquired from Dentistry School. The enamel and dentine samples were separately from each other and then washed using acetone and purified water. These samples were dried at 40 0C during about 24 h and ground in an agate mortar for analyses. Instrumental neutron activation analysis (INAA) followed by gamma ray spectrometry was applied in these analyses and the elements Ca, Cl, Mg, Mn, Na, Sr and Zn were determined. Dentine and enamel result comparisons between both the adult and child group are being done. Element concentrations obtained for enamel and dentine tissues indicated significant difference for the elements Cl, Mn and Sr. Element present in deciduous teeth were the same magnitude of those obtained in permanent teeth. The certified reference materials NIST 1400 Bone Ash and NIST 1486 Bone Meal were also analyzed to control the quality results. Acknowledgments: To FAPESP and CNPq for financial support 66 243 NEUTRON ACTIVATION EXPERIMENTS FOR BREMSSTRAHLUNG CHARACTERIZATION STUDIES D.R. Reinert and S.R. Biegalski, The University of Texas at Austin. Activation experiments were conducted to assess the bremsstrahlung continuum produced when a beta emitter is shielded by metals such as aluminum, steel, tungsten, and lead. Emphasis has been placed on the neutron activation of the 7Li isotope and the subsequent short-lived 13 MeV beta decay of 8Li (T1/2=838 ms). The chemical and corrosive properties of 7Li liquid metal coolant generally mandate the use of refractory alloy container metals and piping. The combination of the 8Li beta decay and the high atomic numbered metals used in piping is a scenario in which bremsstrahlung production is a principal shielding concern. A series of fast pneumatic activation experiments have been performed to obtain the spectral distributions of bremsstrahlung gamma-rays transmitted through shield samples of varying thickness. Detectors were used in both pulse height and multichannel scaling analysis modes for energy spectra determination and half-life verification, respectively. Experimental results were utilized to validate the probabilistic condensed history method of electron transport and bremsstrahlung production used in the MCNP code. A simple and rapid method of Tc99 in environmental samples Sigeru Bamba, Keisuke Isogai, Yoshihiro Ikeuchi, Kaneaki Sato Japan Chemical Analysis Center. A simple and rapid method has been developed for the determination of 99Tc in environmental samples, such as drinking water, vegetable, milk and soil. In this method, Re is added to obtain the chemical yield. 99Tc is leached out from pretreated samples using nitric acid， and Tc was reduced to Tc(IV) using potassium disulfite and coprecipitate using iron(II) hydroxide to concentrate 99Tc from the leached solution. 99Tc is separated and purified with a solid extraction disk (3M Technetium RAD disk). 99Tc is determined using the inductively coupled plasma mass spectrometry (ICP-MS). The decontamination factor of Ru, which is interfered in 99Tc measurement using ICP-MS, is 6.0×105. Five samples spiked 99Tc were analyzed to confirm the validity of this method. The chemical yield was from 63 to 85%, and the 99Tc concentration in five samples was good agreement with the spiked value. Using this method, 99Tc is analyzed within 24 hours, and the detection limit is 0.01Bq/kg (dry soil) for 10g soil. This method does not need to use RI such as 95mTc and 99mTc, so this method is carried out in the common laboratory. LIMITS AND OPPORTUNITIES OF INAA DETERMINATIONS IN SERUM AND BRAIN TISSUE SAMPLES Rolf Zeisler, Elizabeth A. Mackey, Analytical Chemistry Division, NIST, and Lin-wen Hu, Nuclear Reactor Laboratory, MIT. Chromium and mercury traditionally have been determined at the lowest levels by radiochemical separations following neutron activation. These dedicated procedures require 246 247 67 a high level of experimental skill and are time-consuming. In addition, they result in higher radiation exposure of personnel and radioactive chemical waste. Therefore a strong incentive exists to explore the boundaries of instrumental neutron activation analysis (INAA) and to define procedures that are fit for the purpose of determining the elements at their naturally occurring levels. For this work, the limits of INAA were studied for the determination of mercury in unique small brain tissue samples and for characterization of the new SRM 1598a Animal Serum. The sensitivity of INAA is dependent on the assay of a sufficient signal above background, the latter being defined 1) by blank contributions to the signal, and 2) by the background in the gamma-ray spectrum. INAA blanks are minimized by sample encapsulation in synthetic quartz vials that do not contain either Cr or Hg at measurable levels. High efficiency gamma-ray spectrometers and anticoincidence counting were applied. The latter can significantly decrease gamma-ray background, in particular the direct interference of 75Se with 203Hg at 279.1 keV. Applying both measures facilitated the determination of 0.3 µg/L Cr and 0.3 µg/L Hg in SRM 1598a Animal Serum, and was used in the study on Hg in brain tissue samples. 248 ANALYSIS OF LOW-COUNT GAMMA-RAY SPECTRA USING SPECTRAL COMPARISON RATIOS Robert Runkle, PNNL. Spectral analysis algorithms that operate in the grey space between recognizing radioactivity and identifying isotopic composition have potential to improve present-day low-count, gamma-ray detection and analysis systems. Low-count environments dominate the landscape of monitoring special nuclear material transport and lost-or-stolen source search scenarios. In roadway monitoring, for example, the measurement time is not a free parameter but is tightly constrained by the specific environment. We report here the method of Spectral Comparison Ratios (SCR). SCR is a technique that detects target sources by comparing counts in pre-defined energy bins based on a matrix of target sources and a benign source population. The algorithm can be tuned to the specific systematic variability in the gamma-ray spectra of a field environment. The integral component of the SCR algorithm is the location of the energy bins, and we discuss the statistical methods used for choosing these locations along with the decision criteria that maximally separate target from benign sources. DISTRIBUTION OF ENVIRONMENTAL RADIONUCLIDES IN SEDIMENT CORE OF THE JINHEUNG CATCHMENT Yoon Yeol Yoon1, Chul Soo Kim2, Dong Yoon Yang1, Kil yong Lee1, Soo Young Cho1 1Korea Institute of Geoscience and Mineral Resources, 2Korea Institute of Nuclear Safety. Sediment core sample taken from Jinheung catchment located middle of Korean Peninsulra was used to compare environmental radiionuclide distribution. Core sample was taken 1 cm depth interval with titanium knife and dried at 60 ℃ for 24 hours in electric oven 249 68 and pulverlzed. The result of grain size analysis showed minimum value at 17 cm depth and this was occurred maybe minimum dry rainfall at 1969. The radionuclides Cs-137, Np-237, Pu-239, Pu-240, U-234, U-238, Th-228, Th-230, Th-232 were analyzed by sector type ICP-MS and gamma spectrometry. And these radionuclides were used to compare activity difference with depth. Cs and Pu distribution were similar with depth and had a maximum value between 14~22 cm depth. This value was due to high activity of nucleae bomb test at air from 1960's and showed different distribution pattern of soil surface. Radionuclide activities did not showed correlation with grain size. The average activity ratio of Pu-240/Pu-239 and Np-237/Pu-239 were 0.173 and 0.45. These values were similar north hemisphere global fallout ratio of Pu-240/Pu-239(0.18) and Np-237/Pu239(0.45). Np-237/Pu-239 ratio showed higher value than global fallout ratio above 14 cm depth. This phenomina was maybe occurred by high solubility and migration characters of Np(V) ion. The U, Th and their daughter radionuclides kept secular equilibrium in sediment core because analyzed average activity ratio of were nearly 1. 250 CLASSIFICATION AND PROVENANCE DETERMINATION OF ARCHAEOLOGICAL POTTERY FROM THE EAST AEGEAN BY NEUTRON ACTIVATION ANALYSIS (NAA) H. Mommsen and M. Kerschner¹ Helmholtz-Institut für Strahlen- und Kernphysik, University Bonn, Nussallee 14-16, 53115 Bonn, Germany, mommsen@hiskp.uni-bonn.de ¹Österreichisches Archäologisches Institut, Franz Klein-Gasse 1, 1190 Vienna, Austria. Instrumental NAA has been used now for about 40 years to determine the minor and trace elemental pattern in archaeological pottery. It is generally accepted today, that this pattern, if measured with high precision, characterizes the clay paste the ancient potters prepared to form and fire their vessels. Up to now, about 800 samples of archaeological ceramics from different production sites in Western Asia Minor and the neighbouring East Greek islands (e. g. Phokaia, Smyrna, Ephesos, Miletos, Sardis, Samos) have been analysed. The time span mainly covered starts at the Bronze Age and reaches until the Archaic and Classical periods. Using multivariate statistical procedures, many different characteristic patterns have been obtained, and most of them could be geographically assigned to a definitive production site or region. It will be shown how these results illuminate the importance of different workshops by determining the range of the ceramic classes produced for local needs as well as for regional and also for far-ranging trade. DETERMINATION OF CADMIUM HIGH-ARCTIC AIR FILTERS BY EPITHERMAL NEUTRON ACTIVATION ANALYSIS AND COMPTON SUPRESSION S. Landsberger, A.Massicotte, J. Braisted, University of Texas, Nuclear Engineering Teaching Lab, PRC, R-9000, Austin, Texas, USA 78712. Arctic pollution is a problem of great concern, because its characteristics 251 69 (transportation, assimilation into the environment, etc.,) are complex and not fully understood. Detection of elemental constituents has been undertaken through the use of Neutron Activation Analysis and Compton suppression (to lower the detection limits for radionuclides characteristic of mainly single gamma-ray emissions) to discover possible pollutant sources. The goal of this project was to perform a feasibility study to determine if neutron activation analysis (NAA) can be used to evaluate cadmium concentrations on air filters collected in the Arctic. 253 RADIOCHEMICAL SEPARATION OF CD-109 FROM A NATURAL AG TARGET K. Aardaneh * and C. Naidoo, iThemba LABS, P.O. Box 722, Somerset West 7129, South Africa. Abstract: A radiochemical separation method was developed for separation of 109Cd from a nat.Ag target (6.6 g, pressed into a 19 mm disc). The method included two stages. In the first stage, after dissolution of the target in nitric acid, silver was separated from Cd by precipitation into metallic form using 20 g turning Cu for reduction of Ag+ ions. In the second stage, 109Cd in the filtrate, that contained trace amount of silver and substantial amount of Cu (I), was purified by use of a Bio-Rad AG1-X10 anion exchange resin. The column was 1.6 cm i.d and 4 cm long with a flow rate of 2 ml/min throughout the separation. 109Cd was quantitatively recovered from the first stage and recovery yield from the ion exchange chromatography was greater than 96%. The concentration of stable isotopes of Ag and Cu in the final solution (10 ml) were measured by an ICP-OES method and found to be 2.2 and < 0.3 ppm, respectively. 2 M HCl containing H2O2 was used for adsorption of Cd and elution of Ag and Cu. 109Cd was then eluted with 100 ml 1 M HNO3. A MULTI-CURIE TM-171 TARGET FOR D.A.N.C.E. Jon M. Schwantes, Robert S. Rundberg, Wayne A. Taylor, and David J. Vieira, Ralf Sudowe*, Heino Nitsche*, and Darleane C. Hoffman*; Los Alamos National Laboratory, Los Alamos, New Mexico, USA; *University of California, Berkeley, California, USA. Preparation of a multi-curie 171Tm (t1/2=1.92a) target is underway for the purpose of measuring neutron capture cross sections using the Detector for Advanced Neutron Capture Experiments (DANCE) located at the Los Alamos Neutron Science Center (LANSCE). Target preparation consisted of three key steps: (1) material production; (2) separation and purification; and (3) electrodeposition onto a suitable backing material. Approximately 2 mg of the target material (at the time of separation) was produced by irradiating roughly 250 mg of its stable enriched 170Er lanthanide neighbor with neutrons at the ILL reactor in France. This production method resulted in a ―difficult-to-separate‖ 1:125 mixture of near-neighboring lanthanides, Tm and Er. To carry out this separation, a high-performance liquid chromatorgraphic (HPLC) method, previously developed for this purpose (Schwantes et al., In Press), was used. To date, the separation and purification step is nearly complete and expected 254 70 to yield a final product approaching 99% purity. The final step will be to electrodeposit the Tm on thin Be foil to a thickness of ~1 mg-cm-2. This paper discusses the major hurdles associated with the separation and purification step including scale-up issues related to the use of HPLC for material separation, the advantages and limitations of using alphahydroxyisobuturic acid (a-HIB) eluent for separating lanthanides, and postcolumn purification of the target material from a-HIB and 4-(2pyridylazo)resorcinol (PAR) colorant. Also presented here are aspects related to the electrodeposition step. These include choosing a suitable backing material and the development of a versatile molecular plating method capable of producing relatively thick, homogeneous, and stable deposits on a variety of backings including Ti, Be, and various metal-coated mylars. 255 APPLICATIONS OF SOLVENT EXTRACTION IN THE HIGHYIELD MULTI-PROCESS REDUCTION/SEPARATION OF Eu FROM EXCESS Sm Jon M. Schwantes, Ralf Sudowe*, Heino Nitsche*, and Darleane C. Hoffman*; Los Alamos National Laboratory, Los Alamos, New Mexico, USA; *University of California, Berkeley, California, USA. A novel multiprocess method for separating Eu from neighbouring lanthanides (Ln) has been developed that chemically reduces Eu(III) to Eu(II) prior to solvent extraction of Ln(III) with thenoyltrifluoroacetone in benzene. This method is capable of achieving higher purities (>99%) and separation yields than previously published multi-process methods that stabilize and separate the reduced Eu(II) as a sulphate solid and is ideal for enriching materials of high-value. Results from a variety of combinations of a chemical or electrochemical reduction process preceding a separation process using either ion exchange chromatography, reversed phase chromatography, or solvent extraction are discussed. NATURAL 32Si AS ENVIRONMENTAL TRACER U. Morgenstern, National Isotope Centre, GNS Sciences, Lower Hutt, New Zealand (U.Morgenstern@gns.cri.nz).. Cosmogenic 32Si, with a half-life of ca. 140 years, is ideally suited to provide time information in the range 301000 years. Detection of 32Si is, however, very difficult due to extremely low natural concentrations and isotopic ratios. At GNS we have developed improved methods for radiometric detection of natural 32Si and, in collaboration with Australian National University, have succeeded in measuring natural 32Si by accelerator mass spectrometry (AMS). Recent developments will be presented in: 32Si analysis of natural samples, temporal and spatial distribution of 32Si, measurement of the half-life of 32Si, 32Si in groundwater, 32Si dating of sediment cores and deep ocean glass sponges. A PROTOCOL FOR UNCERTAINTY ASSESSMENT OF HALF- 256 257 71 LIVES S. Pommé, R. Van Ammel, J. Paepen, EC-JRC-IRMM, Institute for Reference Materials and Measurements, Retieseweg 111, B-2440 Geel, Belgium.. Nuclear data evaluators are frequently confronted with the problem of deriving a recommended value and an associated uncertainty from a discrepant set of data. This issue is particularly apparent in the case of half-lives of radionuclides. A recent evaluation shows that, for the majority of the radionuclides, the spread of experimentally determined half-life values is larger than expected from the claimed accuracies. Lack of reliable data leads to recommended values based on a few discrepant data, requiring subjective judgement of the evaluator to identify possible outliers and to adjust unbalanced weighting among the accepted data. The situation is often aggravated by experimenters providing insufficient detail on how the halflife and its uncertainty were determined. The latter is clearly underestimated in many cases. Whereas in recent years more attention is being paid to traceability of results and comprehensiveness of the uncertainty budget, there is no common procedure on how to achieve realistic uncertainties, nor on a concise but complete reporting style. In this work, an attempt is made to provide an alternative data analysis method that leads to a complete and realistic uncertainty budget. A procedure is presented in which experimental uncertainties are subdivided into categories according to the rate at which they occur; i.e. at a low, medium or high frequency. Applying the above method, a limited literature review is done for radionuclides of which the experimental data show a high discrepancy. 258 NEW GAMMA-RAY INTENSITIES FOR THE 14N(N,g)15N HIGH ENERGY STANDARD AND ITS INFLUENCE ON PGAA AND ON NUCLEAR QUANTITIES T. Belgya, Institute of Isotopes of the Hungarian Academy of Sciences H1525, Budapest, POB 77. The 14N(n, g)15N reaction is a primary source of high energy gamma-rays for use in calibration of detectors. The gamma ray intensities of 15N and the detection efficiency function have been simultaneously determined from peak areas alone using a new kind of intensity balance calculation. It is based on the assumption that the 15N decay scheme is complete. From the internal consistency of the resulting intensities and the derived efficiency function, it is believed that they are more accurate than previously published values. Effect of the new nitrogen standard intensities on partial gamma ray production cross sections is obvious. Its effect on capture cross sections and PGAA will also be assessed. As a consequence cross section related model calculations, such as decayheat, absorbed dose etc. will also be affected. FIRST EXPERIMENTS ON A NEW IN-BEAM MÖSSBAUER SPECTROSCOPY STATION AT THE BUDAPEST RESEARCH REACTOR T. Belgya and K. Lázár, Institute of Isotopes of the Hungarian Academy of 259 72 Sciences H-1525, Budapest, POB 77. Mössbauer spectroscopy provides information about chemical bonds, oxidation states, geometrical location and magnetic state of the Mössbauer isotope as influenced by its surrounding atoms. Our new in-beam Mössbauer instrument has been constructed at the Budapest Research Reactor. During the on line operation a beam of guided cold neutrons produce the Mössbauer transitions continuously. The neutron flux is measured to be about 109 n×cm-2×s-1 at the target position. The Mössbauer cryostat can be operated in the 3 K to 360 K temperature range. For data acquisition a Na(Tl) or a HPGe, can be used in absorption geometry. The surface areas of the Mössbauer source and absorber are about 1 cm2. Prospective prompt-gamma nuclei for in-beam excitation are identified (40K, Gd, Er, Dy, Yb, 179Hf, 188Os, 201Hg). The short-lived continuously activated sources and the corresponding Mössbauer nuclei (153Er, 166Er, 175Lu, 186Os, 191,192Ir, 195Pt, 197Au) can also be used in beam. Longer half-life nuclei can be activated in the reactor and used during the reactor shutdown periods (141Pr, 127I, 129I, 181Ta, 182W). Fields of application includes biological systems (40K), catalysis (Au, Pt), HTC superconductors (Pr), granite and magnetic layers (Gd, Er, Dy, Yb) or the chemical behavior of the nuclear waste of 129I. 260 COMPUTER CODE FOR EXACT DETECTION LIMITS AND ERRORS OF THE SECOND KIND FOR LOWER LEVEL COUNTING WHEN THE BLANK COUNT TIME IS AN INTEGER IN [1, 20] TIMES GREATER THAN THE SAMPLE COUNT TIME W. Potter and Jodi Strzelczyk. In the past computer codes were developed to compute exact decision levels and errors of the first kind when the blank count time is an integer in [1, 20] times greater than the sample count time. The blank count and the contribution of the sample to the gross count are assumed to be Poisson distributed. The expected value of the blank count is assumed to be known. This paper extends the previous work for decision levels to detection limits for lower level counting. After transforming the net count to an integer, the probability density function for the transformed net count can be readily determined when the transformed net count is greater than zero. The right tail of the distribution is summed and the detection limit is determined to four decimal places using a simple search. The code under discussion works well when the product of the ratio of the blank count time to the sample count time with the expected blank count in the sample count time is not greater than 100.0. This restriction to lower level counting enables a double precision code to make the necessary computations; a long double precision code is necessary to extend the results to higher levels. The desired errors of both the first and second kinds are taken to be in the interval [0.01, 0.1]. The validity of the computation is verified by summing over all transformed net counts when there is no activity present and comparing with one and by computing the expected value of the net count when there is no activity present and comparing with zero. Furthermore the actual errors of both kinds are output for comparison with the desired errors 73 of both kinds. When the desired errors of both kinds are equal, the results of the generalized Currie-Brodsky formulation are applicable; these results are checked with the exact results. 261 A PCNAA METHOD FOR THE DETERMINATION OF 232TH IN A DRY-TUBE IRRADIATION ENVIRONMENT Gels, J.L.; Spitz, H.B.; Glover, S.E. Department of Mechanical, Industrial and Nuclear Engineering, University of Cincinnati. A revised method for determining 232Th in urine using a pre-concentration neutron activation analysis (PCNAA) procedure was developed to accommodate irradiation in a 500 kW light water, low enriched fuel, natural convection pool-type nuclear research reactor. Thorium-232 extracted by ion exchange from a sample is electrodeposited onto 5/8‖ diameter vanadium planchets, which are arranged in a stack and irradiated in the dry tube central irradiation facility (CIF) of the reactor. The higher neutron fluence of this facility improved sensitivity by approximately 37%, however the higher temperatures required modifications to the irradiation procedure. Because the heat in the CIF would melt the plastic spacers used in the original method, a tube of highpurity quartz was used to contain samples, and high purity quartz spacers were used to separate the vanadium planchets during the irradiation. Results of the experiments to evaluate and verify the method are described. Also, a thin film barrier was tested for its ability to reduce recoil contamination of the detector during alpha spectroscopy. The film was shown to reduce contamination to levels indistinguishable from normal background. RESULTS FROM A PILOT STUDY ON THE DENDROCHRONOLOGICAL ANALYIS OF URANIUM IN TREE RINGS NEAR A FORMER DEPARTMENT OF ENERGY FACILITY Sandwall, P.1; Mitchell, T.1; Elliston, J.T.2, Spitz, H.B.1; Glover, S.E.1 Department of Mechanical, Industrial and Nuclear Engineering, University of Cincinnati. In an attempt to create a historical portrait of uranium pollution from a former uranium processing facility, increment cores were collected from sugar maples (Acer saccharum) at locations with groundwater incident the Fernald Site. Samples were sectioned into four year increments, and shipped to Washington State University where they underwent neutron activation analysis. Consecutive counts were made of uranium decay products via gamma-ray spectrometry at Washington State University and the University of Cincinnati. Results forthcoming. NEUTRON ACTIVATION ANALYSIS DATA OF AIR-FILTERS COLLECTED IN SPOKANE WA. Daniel Dugan, WSU-NRC; Dr. Roy Filby, WSU Chemistry; Dr. James T. Elliston, WSU-NRC; Dr. Paul Buckley, Lewis and State College; Dr. Candis Claiborn, WSU Environmental Engineering. More than 2200 air particulate matter filters were collected from 1995 through 2002 in the Spokane, WA area for the Spokane Air-filters project. The samples were sent to the US 262 263 74 EPA in Research Triangle Park, NC for energy dispersive x-ray fluorescence (XRF) analysis and then delivered to the Washington State University Nuclear Radiation Center for neutron activation analysis (NAA). There were 28 elements of interest for the NAA portion of the project; however, due to detector efficiencies, background effects, and composition loading on each filter, only 15 of the 28 elements analyzed for produced valid results above the detection limit due to Compton background noise and blank subtraction. The 15 detectable elements with their six year average with associated 95% confidence interval concentrations in ng/m3 are: As (0.384 ± 0.88), K (50.0 ± 194), La (0.051 ± .0251), Na (61.9 ± 421), Sm (0.00928 ± .072), Au (0.00154 ± 0.149), Br (1.06 ± 1.5), Ce (0.164 ± 0.969), Co (0.0399 ± 0.122), Cr (0.479 ± 3.31), Fe (110 ± 227), Sb (0.474 ± 1.64, Sc (0.0197 ± .00548), Th (0.011 ± 0.0603), and Zn (12.4 ± 32.6). 264 THE ONE SOURCE COHORT - EVALUATING THE SUITABILITY OF THE HUMAN TOENAIL AS A MANGANESE BIOMONITOR Guthrie, James M.; Brockman, John D.; Morris, J.S; Robertson, J.D. University of Missouri Research Reactor.. Numerous studies have demonstrated that the human toenail is a reliable biomonitor for the tracenutrient Se and for the toxic trace elements As and Hg. The objective of this study was to evaluate the use of the toenail as a biomonitor for Mn. A cross-sectional study was performed by selecting 126 samples from archived toenail specimens from self-identified consumers of the One SourceTM multivitamin and matched controls. One Source was chosen due to this supplement's high content of Mn and Se. Se was first measured using established methods and an NAA procedure was developed that allowed for the simultaneous determination of Mg, Ca, V, Cu, Mn, and Zn. The Se results confirmed that the cohort was accurately classified in terms of multivitamin supplementation. The preliminary analysis of Mn results does not indicate a significant correlation between toenail levels and multivitamin intake. There is, however, a strong correlation between concentrations of Mn and potential contamination markers, suggesting that a multivariate analysis of the data is necessary in order to correct for exogenous influences. AN EXPEDITED, ROBUST METHOD FOR THE ELECTRODEPOSITION OF ACTINIDES A. Plionis (UT), D. Haas (UT), S. Landsberger (UT), G. Brooks (LANL). Several methods for the electrodeposition of actinides for alpha-spectrometry analysis have been developed over the past few decades, but none have been specifically designed to facilitate rapid analysis in a field situation. The goal of this project is to develop an electrodeposition procedure and automated devices to assist in execution. Mobile labs would be able to use these techniques to obtain preliminary results in the event of a radiological incident. A sodium bisulfate-sodium sulfate electrolyte was chosen as basis for the adaptive method. This electrolyte utilized was first described by Kressin and later investigated by Bajo, who described it as "robust." The 265 75 procedure was performed as described by Bajo except that the current density was increased from 0.457 A/cm2 to 0.606 A/cm2, allowing for a reduced deposition time while still achieving good results. Quantitative yields with associated uncertainties have been determined for the NaHSO4Na2S2O4 electrolyte. It has also been shown that short deposition times can provide quantitative results. In addition, a prototype for the automated electrodeposition device has been built and used to achieve the stated results. 266 COMPTON SUPPRESSION SYSTEM AT PENN STATE RADIATION SCIENCE AND ENGINEERING CENTER N. Ö. ÇETİNER, K. ÜNLÜ, J.S. BRENIZER. A Compton Suppression System (CSS) is used to reduce the contribution of scattered gamma rays that originate within the HPGe detector to the gamma ray spectrum. In CSS the HPGe detector is surrounded by an assembly of guard detectors, usually NaI(Tl). The HPGe and NaI(Tl) detectors are operated in anti-coincidence mode. The NaI(Tl) guard detector detects the photons that Compton scatter within, and subsequently escape from, the HPGe detector. Since these photons are correlated with the partial energy deposition within the detector, much of the resulting Compton continuum can be subtracted from the spectrum, reducing the unwanted background in gamma ray spectra. A commercially available Compton Suppression System was purchased and tested at the Radiation Science and Engineering Center at Penn State University. The PSU-CSS includes a reverse bias HPGe detector, four annulus NaI(Tl) detectors, a NaI(Tl) plug detector, detector shields, data acquisition electronics, and a data processing computer. The HPGe detector is n-type with 50% efficiency. The guard detectors are on an annulus with 9inch diameter and 9-inch height, plug detector that goes into/out of the annulus with the help of a special lift apparatus to raise/lower. The detector assembly is placed in a shielding cave. State-of-the-art electronics and software are used. Detailed information about the setup and operation of the CSS at Penn State University, along with preliminary testing results for the CSS system characteristics will be presented. Examples from ongoing research on Neutron Activation Analysis of Dendrochronologically dated tree ring samples and carbon nanotubes will be discussed. DEVELOPMENT AND APPLICATIONS OF TIME-OF-FLIGHT NEUTRON DEPTH PROFILING Sacit M. Çetiner, Kenan Ünlü (Penn State University, Department of Mechanical and Nuclear Engineering), R. Gregory Downing (NIST). Neutron depth profiling (NDP) is a three-decade old surface analysis technique, which is based on the illumination of samples with thermal or sub-thermal neutrons, and subsequent release of charged particles. Upon neutron absorption, certain isotopes undergo exoergic reactions that emit either a proton or alpha, and a recoil nucleus. Particle emission is monoenergetic and isotropic, which simplifies the analysis of reaction kinematics. Emitted particles rapidly lose kinetic energy through stochastic 267 76 interactions with the electrons of the material. The energy loss is directly related to the depth of the original emitter and can be found by using stopping power correlations. In the conventional NDP, particle residual energy is measured directly by using a silicon semiconductor detector, mostly either one of surface barrier detector (SBD), passivated implanted planar silicon (PIPS) detector, or silicon PIN photodiode. The detection mechanism in semiconductor detectors introduces additional uncertainties in the measured energy of charged particles, which results in energy spread hence loss of depth resolution. It is shown that, for a 200-nm borophosphosilicate glass (BPSG) sample, the uncertainty introduced by a silicon semiconductor detector accounts for almost 60% of the total uncertainty for alpha particles resulting from 10B(n, α)7Li reaction. In Timeof-flight NDP (TOF-NDP), particle flight time is measured instead of particle energies. Time measurement is more sensitive than the energy measurement. Silicon semiconductor detectors can be replaced by microchannel plates (MCP) since no energy proportional output is needed in time-of-flight configuration. It will be shown that the depth resolution of aforementioned test sample can be improved by a factor of 5 by TOF-NDP. More dramatic resolution improvement is possible for heavier and/or slower particles emitted by the neutron capture reaction. In this study, TOF-NDP concept will be briefly explained; Penn State TOF-NDP facility will be introduced. Preliminary measurements, both offline and online, will be presented. 268 DELAYED NEUTRON ACTIVATION ANALYSIS FOR SAFEGUARDS David Glasgow, Oak Ridge National Laboratory. Delayed neutron activation analysis (DNAA) presents a fast, accurate, and reliable method for quantification of fissile material. The method has relatively few sources of error and may be accomplished nondestructively. The Oak Ridge National Laboratory has employed DNAA for the analysis of hundreds of thousands of materials over the past thirty years. The need for a fast, accurate screening of materials stems from the necessity to protect cleanroom facilities from widely varying fissile quantities in samples and from desired gains in efficiency of mass spectrometric analysis by assisting in spike level selection and by removing from the sample set those materials that are not of interest. During the last several years, many different materials have been screened or analyzed in support of international safeguards, internal process control for actinide separations, and in uranium contamination assessments. Swipes from a variety of sources have been analyzed either before or after dissolution and comparison of the DNAA results to mass spectrometry results is generally favorable. A facility characterization of the High Flux Isotope Reactor was performed using filter paper swipes to demonstrate the utility of the DNAA technique. These data along with a complete uncertainty treatment are presented. 77 269 Detection Limit Improvements Forecasted at CTBTO IMS Radionuclide Stations Based on Size Separation of Aerosols by Aerodynamic Diameter S. Biegalski (The University of Texas at Austin), O.A. Ezekoye (The University of Texas at Austin), J. Rynes (General Dynamics), M. Pickering (General Dynamics), J. S. Maikell (The University of Texas at Austin), J. M. Jeña (The University of Texas at Austin). Studies show that aerosols with natural activity have an aerodynamic diameter in the range of 0.1 to 1 mm. In contrast, atmospheric nuclear explosions produce radioactive aerosols with aerodynamic diameters less than 0.1 mm. Surface nuclear explosions produce a bimodal distribution of radioactive aerosol particles. The first group of particles in a surface explosion is produced by spontaneous nucleation and is very similar in distribution to that of the atmospheric explosion. These particles do not combine with material from the ground entrained within the explosion and have aerodynamic diameters less than 0.1 mm. The second group of particles from a surface explosion contains admixed particles entrained in the explosion and has particles with aerodynamic diameters greater than 1 mm. These differences in aerosol sizes are quite fortuitous because they allow aerosol aerodynamic diameter to be utilized as a physical property to separate aerosols of natural origin from those produced in a nuclear explosion. Measurements of size separated aerosol samples collected in Austin, TX have been made to determine the detection limits for key fission products as a function of aerosol particle diameter. These data were then utilized to forecast detection limit improvements possible at CTBTO IMS radionuclide stations provided an aerosol size separation capability. Scanning Electron Microscopy and Energy Dispersive X-Ray Analysis of particles from the Metropolitan Zone of the Valley of Mexico T. Martinez1*, J. Lartigue1, P. Avila-Perez2, L. Carapio-Morales2 , G. Zarazua2, M. Navarrete1, S. Tejeda2 1National University of Mexico, Faculty of Chemistry, CU (O4510) Mexico, D.F. (Mexico). e-mail: tmc@servidor.unam.mx 2National Institute of Nuclear Research. Carr. México-Toluca Km 36.5, (52045) Salazar, Ocoyoacac, Mex. (Mexico). . Air survey was carried out in the Metropolitan Zone of the Valley of Mexico with high volume samplers (average flow rate of 1.5 m3 min-1) during 24 h in five monitoring stations of the national network system. 1 cm2 was cut from each filter and the analysis of 100 individual particles of each size (Total Suspended Particles, TSP, and Respirable Particles, PM10, so totalizing 1000 particles) was performed by Scanning Electron Microscopy (SEM) and Energy-Dispersive X-ray Microanalysis (EDXA) in a Scanning Electron Microscope Philips-XL-30 and an Energy-Dispersive X-ray Si(Li) Detector Saphire-SUTW, allowing a complete chemical elemental analysis (Z -ray data were corrected by a blank filter factor, then normalized to give the weight percentage of each detected element in the individual particles. Some criteria were applied to identify 270 78 groupings of compositionally-similar particles types. Hevy metals group and carbon, firstly in soot aglomerate form, were observed in all samples. It is discussed some correlation with possible sources and effects to human health. 271 STARTING A RADIOCHEMISTRY EDUCATION AND RESEARCH PROGRAM AT PENNSYLVANIA STATE UNIVERSITY K. Ünlü, G. L. Catchen, J. S. Brenizer. Nuclear Chemistry and Radiochemistry programs were in a sense the driving force of nuclear science education and research in the USA during the 1950-80‘s. The Pennsylvania State University (PSU) had been a perfect example of this history. Almost half of the existing laboratory space at the Radiation Science and Engineering Center during the 1960-80‘s was dedicated to radiochemistry teaching and research laboratories. However, the interest in radiochemistry declined nationwide in the early 1980‘s and the radiochemistry activities became limited to several small programs at PSU. We started to change this trend and revitalize our radiochemistry education and research program at PSU with a recent support from the Department of Energy, Radiochemistry Education Award Program. The PSU radiochemistry program primarily addresses radiochemistry education and secondarily nuclear and radiochemistry research. The education program consists of bolstering our existing radiochemistry and related courses; Nuclear and Radiochemistry, Radiation Detection and Measurement, Radiological Safety and developing new courses, e.g., Laboratory Experiments in Applied Nuclear and Radiochemistry, Nuclear Methods in Science. We also plan to revitalize the nuclear and radiochemistry research programs. We recently completed a state-of-the-art Neutron Activation Analysis Laboratory. A new gamma ray spectroscopy laboratory that has 10 stations including state-of-the-art nuclear spectroscopy hardware and software was recently completed. In addition, we embarked on an expansion plan that included building a new neutron beam hall and neutron beam ports with a cold neutron source. One of the reasons to have a cold neutron source is for the development of prompt gamma activation analysis facility. Also, we will refurbish some equipment used for Perturbed Angular Correlation Spectroscopy and Mössbauer-effect for the purpose of initiating new radiochemistry research. With this paper a detailed description of PSU radiochemistry education and research program will be given and the future plans will be discussed. The Role of Spectroscopy Versus Detection For Border Security and Safeguards Richard T. Kouzes, Pacific Northwest National Laboratory. Countries around the world are deploying radiation portal monitor (RPM) systems and other radiation detection instrumentation to interdict the illegal shipment of radioactive material crossing international borders. These efforts include deployments in the U.S. and in a number of other countries by governments 272 79 and international organizations. Because of their high efficiency for gammaray detection, most deployed RPM systems are based on plastic scintillators. Such systems, however, are largely non-spectroscopic in capability. Fully capable spectroscopic portal monitor (SPM) systems are undergoing engineering development for deployment in the future. The ability to identify the detected radionuclides may allow improved operational handling of radiation alarms, particularly those arising from the normal cargo stream of naturally occurring radioactive material (NORM), commercial radioactive sources, and individuals treated with medical radiopharmaceuticals. The goal for improved RPM systems is to increase the sensitivity to threats while reducing the impact that nuisance alarms have on operations. This presentation considers the roles for spectroscopic and non-spectroscopic systems for safeguards. 273 BAYESIAN ANALYSIS FOR VERY-LOW-BACKGROUND COUNTING OF SHORT-LIVED ISOTOPES Kirk Mathews, Air Force Institute of Technology. Conventional statistical analyses of counting measurements with a paired-count blank and sample yield unacceptably-large estimates of uncertainty that reduce measurement sensitivity when applied to very-low-background detection systems. Here, Bayesian analysis using longer background counts, either with an estimated parametric distribution of background or with empirical distribution estimates obtained by bootstrapping, is combined with a binomial distribution of actual decay counts that accounts for sample decay during the count interval is presented. Thus, the analysis treats decay and background counts differently, rather than relying on net counts. With short-lived samples, count duration can be adjusted to optimize sensitivity. These analyses are computationally intensive, requiring an exact-statistics approach, but are practical with today's microcomputer capablities. SIMULTANEOUS ANALYSIS OF PLUTONIUM AND URANIUM BY ISOTOPE DILUTION GAMMA-RAY SPECTROMETRY (IDGS) TECHNIQUE Tien Keh Li, LANL, N-1. We have studied the simultaneous determination of concentrations and isotopic compositions for plutonium and uranium in input spent-fuel dissolver solutions at a reprocessing plant and mixed oxide (MOX) product solutions at a fuel fabrication plant by isotope dilution gamma-ray spectrometry (IDGS) technique. The isotopic compositions are determined by high-resolution gamma-ray spectroscopy. To measure the plutonium concentration, the unknown solution is spiked with plutonium of accurately known plutonium mass and isotopic composition. For dissolver solutions, the unknown and spiked solutions are subsequently measured using high-resolution gamma-ray spectrometry following the fission product separations by extraction chromatography using U/TEVA•Spec resins. The U/TEVA•Spec method is used to separate fission products and recover both uranium and plutonium in the samples from dissolver solutions. The results 274 80 of plutonium concentrations and isotopic compositions and uranium/plutonium ratios of dissolver solutions and MOX product solutions measured by IDGS agree very well with those obtained by traditional isotope dilution mass spectrometry. The rapid and accurate IDGS technique could provide a timely, less expensive, and simpler on-site verification method and accountability measurement for domestic and international safeguards. 275 Reactor Safeguards using Compact Antineutrino Detectors Nathaniel Bowden, Matthew Allen, Jim Brennan, Jim Lund (Sandia National Laboratories, CA), Adam Bernstein, Chris Hagmann, Celeste Winant (Lawerence Livermore National Laboratory). Fission reactors emit large numbers of antineutrinos and this flux may be useful for the measurement of two quantities of interest for reactor safeguards: the reactor's power and plutonium inventory throughout its cycle. The high antineutrino flux and relatively low background rates means that simple cubic meter scale detectors at tens of meters standoff can record hundreds or thousands of antineutrino events per day. To access information about plutonium content, we exploit the fact that the ingrowth of 200-300 kilograms of plutonium in the core across a typical 1.5 year fuel cycle induces a predictable roughly linear fall-off in the antineutrino rate in that time. Such antineutrino detectors would add online, quasi-real-time bulk material accountancy to the set of reactor monitoring tools available to the IAEA and other safeguards agencies with minimal footprint and impact on reactor operations. Possible benefits from this approach include the ability to compare direct measurements of composition with declarations and other IAEA material accountancy metrics; a decrease in the time to detect unauthorized diversion of fissile material; less intrusiveness for operators, reduced inspection frequency for the safeguards agency, and cost savings from the standpoint of both the reactor operator and the safeguards agency. Our SNL/LLNL collaboration has deployed a prototype safeguards detector at a reactor in Southern California in order to test both the method and the practicality of its implementation in the field. Here I present results from this prototype detector and discuss further steps needed for practical implementation of this technique. Background concentration of 14C in aquatic samples from brackish Lake Obuchi, Japan, adjacent to nuclear fuel reprocessing facilities Shinji Ueda, Kunio Kondo, Jiro Inaba. Brackish Lake Obuchi in Rokkasho, Japan, locates adjacent to the Japanese first commercial nuclear fuel reprocessing plant now under performing U-testing. To study the effect of radiocarbon (14C) released from the plants in future to the 14C concentration in aquatic samples, background level of 14C was measured for water, biota and sediment samples from 2002 to 2004. Mean (±SD) of 14C concentrations in lake water samples was 98±5 PMC and slightly lower than that reported for the atmosphere (approximately 105 PMC). Depth profile of 14C in three core samples, which were cut at 5 cm intervals to 50 or 55 cm deep, showed maximum concentrations of 14C varied from 103 PMC to 106 276 81 PMC at 5-10 cm to 15-20 cm deep. The 14C concentrations in biota (plankton, benthos and fish) of the lake showed approximately 105 PMC, and the difference among biota was small. 277 ACTIVATION STUDY OF METAL TARGETS BY LIGHT CHARGED PARTICLE INDUCED NUCLEAR REACTIONS F. Tárkányi1, F. Ditrói1, S. Takács1, F. Szelecsényi1, B. Király1, J. Csikai1 A. Hermanne2, M. Sonck2, M. S. Uddin3, M. Hagiwara3, M. Baba3, T. Ido3, Yu. N. Shubin4, S. F. Kovalev4, A. Dityuk4 1Institute of Nuclear Research of the Hungarian Academy of Sciences (ATOMKI), Debrecen, Hungary, 2Cyclotron Laboratory, Vrije Universiteit Brussel, Brussels, Belgium, 3Cyclotron and Radioisotope Center, Tohoku University, Sendai, Japan, 4Institute of Physics and Power Engineering, Obninsk, Russian Federation. Integral excitation functions for the production of residual nuclides with light charged particles are basic data for applications in radioanalytical analysis for biomedical research and wear control by TLA, monitoring of processes around modern accelerators and medical radioisotope production. No systematical study has been performed earlier and in addition the published data (except for a few well measured monitor and medically important reactions) show large discrepancies. We hence performed a systematical experimental study of light charged particle induced activation cross sections for different targets during the last years. Here we summarize the results for the most widely used technological materials: i.e. for metals. The targets were irradiated with external beams of the cyclotrons of Debrecen, Brussels and Sendai up to 80 MeV. The investigation includes a few hundred reactions induced on the following 28 target elements: Al, Ti, Fe, Co, Ni, Cu, Zn, Y, Zr, Nb, Mo, Rh, Pd, Ag, Cd, Sn, Sb, Te, Er, Yb, Ta, W, Ir, Pt, Au, Tl, Pb, Bi. A significant part of the measured data is new. The measured excitation functions were compared with the theory .A systematic comparison for the different incident particles allows conclusions on the reliability of description of the reaction mechanisms used in the codes. INVESTIGATION OF EXCITATION FUNCTIONS OF DEUTERON INDUCED NUCLEAR REACTIONS ON LEAD Tárkányi F.1, Ditrói F.1, Takács S.1, Uddin M.S.2, Hagiwara M.2, Baba M.2, Ignatyuk A.3, Kovalev S. F.3, Hermanne A.4 1Institute of Nuclear Research of the Hungarian Academy of Sciences, Debrecen. Hungary, 2Cyclotron and Radioisotope Center, Tohoku University, Sendai, Japan, 3Institute of Physics and Power Engineering, Obninsk, Russian Federation, 4Cyclotron Laboratory, Vrije Universiteit Brussel, Brussels, Belgium. Activation data of lead are of great importance due to the widespread applications of this element in various technological fields and to the well known adverse effects to biological systems. Use of high sensitivity radioanalytical techniques allows study of uptake, distribution and speciation. Cross-sections of deuteron induced nuclear reactions on lead were measured 278 82 up to 40 MeV using the standard stacked foil irradiation technique and high resolution gamma-ray spectrometry. Experimental cross-sections and derived integral yields are reported for the natPb(d,xn)203,204,205,206,207Bi, natPb(d,x)203Pb202Tl reactions. Only one set of controversial experimental cross-section data was found in the literature. The experimental data are analyzed and compared with the results of the theoretical model code ALICE-IPPE and with the experimental integral yield reported in the literature. The application of the new cross-sections for analytical purposes, for production of tracers in thin layer activation wear studies and for calculation of activation and doses to operating personnel around accelerators and ADS systems is discussed. 279 RADIOCHEMICAL APPROACH TO THE ASSESSMENT OF THE ENVIRONMENTAL STATE OF KOTOR BAY (MONTENEGRO) S.Degetto1, C.Cantaluppi1, D.Desideri2, M.Schintu3, S.Stanković4, Z.Kljajić5. 1ICIS-CNR Adr C.so Stati Uniti 4 35127-Padova(Italy); 2Dip.Chimica Gen.Univ. di Urbino p.zza Rinascimento 6 61029Urbino(Italy); 3Dip.Igiene e Sanità Pubblica Univ.di Cagliari v.Porcell 4 09100-Cagliari(Italy); 4TMF, University of Belgrade, 11000 Belgrade, Karnegijeva 4, (SCG); 5Institute of Marine Biology, Kotor, Montenegro, 85330, Kotor, (SCG).. Sustainable development and responsible care are imperatives in countries where it is possible to conjugate properly development and environmental protection; this implies: -the introduction of advanced technologies to minimise and control emissions in the environmental compartments. -the recovery of the already compromised natural environments. The aquatic systems represent the ultimate sink of all wastes dispersed in fresh waters and in the soil and subsequently are the most potentially affected bodies of the ecosystem. Sediments are known to play a key role in the cycling of pollutants in the aquatic environments, since they may act both as a sink and a source of widely differentiated chemicals, most of which, potentially hazardous. Owing to this peculiarity, therefore, sediments reflect both past and present conditions of a given water body, providing a detailed and immediate picture of local pollution history. On the other side, water bodies support complex communities of living organisms, typically linked by food chain connections; species highly sensitive, and therefore critical in respect to bioaccumulation of toxic substances, are often included. The radiochemical characterisation of sediments in contaminated aquatic systems has gained increasing interest in as much as this activity is almost unique to obtain information critical for the environmental recovery: -the evolution tendency of the system in terms of erosion/sedimentation. -the determination of the inventory of the anthropic fraction of micropollutants present in the system. -the identification of the natural background (pre-industrial) concentration for each single micropollutant. In the present note we report the past and present environmental impact of anthropic activities (Persistent Organic Pollutants and Heavy Metals) on Kotor Bay and the possible future evolution of the 83 system. The reconstruction of the rate of sediments deposition during time will be obtained by determination of the profile with depth of the activity concentrations of some natural and artificial airborne radionuclides, in particular 210Pb and 137Cs in a series of five sediment cores collected at about 20-25 m depth in the Bay of Kotor. Cores about 1 m long were carefully collected with plastic liners using divers, to core by hand, in order to be precise on where the cores were taken from and the local level of disturbance. Preliminary data indicate a significant variability in the inventories of fall-out radionuclides. Data regarding the sampling campaign conducted during October 2005 form the basis of this communication. 280 Analysis of the kinetic stability of Yttrium complexes using Free-ion Selective Radiotracer Extraction D. Jurkin, B. Wierczinski; Institut für Radiochemie der TU München, Garching (D). Transition metal complexes have wide application in industry, research and medicine. In many cases their exact chemical form (chemical species) during the application is not known. For medical use e.g. in pharmaceuticals, it is, however, indispensable to determine their kinetic stability in order to ensure their effectivity. In this study, the so called Freeion selective radiotracer extraction (FISRE) technique was used in order to analyze the dissociation/association properties of a series of Yttrium(III)complexes including chelating ligands DOTA, EDTA, NTA, CDTA, DTPA, citric acid as well as humic acid. Furthermore, the kinetic stability of 90YDOTA-Tyr-Octreotide, used in radioimmunotherapy for neuroendocrine tumor treatment, was tested. The actual determination of the kinetic stability of the yttrium complexes via FISRE was carried out in two modes, namely by following dissociation as well as association reactions. The extractions were performed with minimised free ligand concentrations and a surplus of free yttrium ions in the mobile phase and the resin. The samples were equilibrated with a negligible amount of a high-specific activity 90Y radiotracer, in the following monitored by Cerenkov counting. Here, the results of the study are presented. These confirm FISRE to be a rapid and very valuable method for kinetic stability analysis. RADIOANALYTICAL DATA QUALITY OBJECTIVES (DQOs) AND MEASUREMENT QUALITY OBJECTIVES (MQOs) DURING A FEDERAL RADIOLOGICAL MONITORING AND ASSESSMENT CENTER (FRMAC) RESPONSE E.C. Nielsen, Bechtel Nevada, Remote Sensing Laboratory-Nellis. During the emergency and intermediate phases of a nuclear or radiological incident that activates the National Response Plan (NRP), the Federal Radiological Monitoring and Assessment Center (FRMAC) collects environmental samples that are analyzed by organizations with radioanalytical capability. During the earliest phase of an incident, analytical data will be urgently needed as a basis for protective actions. The resources dedicated to quality assurance (QA) activities must be sufficient to assure that appropriate 281 84 radioanalytical Measurement Quality Objectives (MQOs) and assessment Data Quality Objectives (DQOs) are met. As the emergency stabilizes, quality assurance (QA) activities will evolve commensurate with the need to reach appropriate DQOs. The MQOs represent a compromise between precise analytical determinations and the timeliness necessary for emergency response activities. Minimum Detectable Concentration (MDC), Lower Limit of Detection (LLD), and Critical Level (Lc) tests can all serve as measurements reflecting the MQO. Combined standard uncertainty must be reported with each analytical result to allow decision makers to estimate the probability of making a decision error. The relationship between Protective Action Guides (PAGs), Derived Response Levels (DRLs), laboratory detection limits, and measurement uncertainties is described. The rationale used to determine the appropriate minimum detectable concentration levels are described. 282 MEASUREMENT OF RADIUM ISOTOPES BY MULTI-ION COUNTING ICP-MS Lary Ball, John Andrews, Ken Sims. Quantification of 226Ra by isotope dilution with 228Ra has applications in geological systems such as ground water movement and uranium series disequilibrium in rocks. Traditional methods such as radiation counting and thermal ionization mass spectrometry have intractable limitations on their precision and accuracy. Use of single collector ICPMS showed great promise for improvement. We present our results using a new generation of multicollector ICPMS (Thermo Electron Neptune) equipped with a new design of channel electron multiplier ion counters coupled with high efficiency sample introduction system and compare with radiation counting methods. Mean Residence Times in Gastrointestinal Tracts of Chickens using Stable Rare Earth Markers and Neutron Activation Analysis W. D. James, Center for Chemical Characterization and Analysis, Texas A&M University, College Station, TX 77843, C.S. Dunkley, W-K Kim and S.C. Ricke, Poultry Science Department, Texas A&M University, College Station, TX 77843. A method has been developed and applied to the study of Mean Residence Times (MRT) of alfalfa molt rations through the gastrointestinal tracts of layer hens. The use of rare earth elements as activatable stable markers in animal digestion studies has been previously demonstrated. The method has proven helpful in measuring rumen fill and flow kenetics and particle breakdown rates for various forages in cattle and has also been applied to studies of horses, goats and sheep. The movement and cultural habits of ants and boll weevils using stable rare earth markers have also been studied. In this study hafnium and europium were used to mark corn and alfalfa rations as well as a combination ration made up of 90% alfalfa and 10% corn. The MRTs were then evaluated using two approaches, the external flow marker dilution rate by compartmental model and the indigestible food (IDF) pool dilution rate . Four groups of 10 hens 283 85 each were fed a particular marked meal with fecal droppings monitored for three days. Fecal dry matter was then activated and the elemental concentrations of hafnium and europium were measured. The presentation will include details of the analytical method and the applicability of the technique for nutrition studeis in chickens. 284 PROMPT DETERMINATION OF EVACUEE RADIATION DOSE FROM A NUCLEAR EVENT PP Bachelor, JI Friese, CE Aalseth, JI McIntyre, RW Perkins, HS Miley and GA Warren, Pachific Northwest National Laboratory. In anticipation of a nuclear terrorist attack, techniques to quickly assess the radiation exposure of evacuees have been developed. Based on past experience relating neutron radiation exposures to activation products, measurement of activation products can be performed in a few seconds. Personal items exposed to significant levels of radiation should allow neutron dose assessment via the activation products. This approach allows prompt collection of important data on human exposure following a terrorist attack. Data collected will facilitate triage decisions for timely emergency medical treatment to ameliorate the radiation effects on exposed individuals. Activation experiments with everyday items exposed to a neutron source will be outlined and presented. The Information Release (IR) request for document PNNL-SA-47796 has been approved by all the reviewers. IMPROVED INJECTION STUDY METHODOLOGY FOR RADIATION PORTAL MONITOR SIMULATION Sean Robinson, Edward Siciliano, John Schweppe (all authors from PNNL). The development and testing of improved alarm algorithms is an ongoing priority of the Radiation Portal Monitor Project (RPMP). Such improved detection methods have the potential to reduce the impediments that RPMs present to the flow of commerce, without affecting the detection sensitivity to sources of interest. Improving algorithm performance is a particularly challenging task, given that laboratory "testing" with actual vehicles, cargo and sources is time consuming and expensive, providing only a small number of example cases when tens of thousands of cases are needed for statistical confidence. A current method for testing algorithms adds (or "injects") modeled count rates of targeted sources to existing source-free vehicle profile data. Typically, these injection studies have the source counts allocated equally over all detectors and do not attempt to correlate the injected source distributions with actual cargo location. To make algorithm testing reflective of actual environments, an effort has been made to build realistic models of RPM systems focused on cargo-screening scenarios. Several different injection techniques are reviewed, and their results are compared with experimental data. In order to ensure a high confidence of results, source data must be injected in a pattern distributed over the detector system in terms of both temporal and spatial axes. An injection scheme is developed, consisting of the modeled background from a drivethrough 285 86 scenario, and a source spectrum scaled for the source position with respect to the detectors. This scheme produces a result similar to actual experimental data. This injection technique combined with the sophisticated models provides a way to quickly produce a large amount of validated drivethrough scenario data that will be instrumental for the improvement of source detection algorithms. 286 TRITIUM ENRICHMENT FROM AQUEOUS SOLUTIONS USING CRYOSUBLIMATION OF MONO- AND POLYSACCHARIDES Birgit Wierczinski, G. Müllen, S. Rosenhauer, A. Türler; Institute for Radiochemistry, Technical University Munich, Walther-Meissner Strasse 3, 85748 Garching, Germany. Aqueous solutions of tritium (HTO) are one of the major radioactive waste products of nuclear power plants. Nowadays, disposal of these liquid wastes is very difficult due to the high volatility of tritium. Therefore we are investigating different techniques to reduce the volume of the HTO waste solutions. One possibility is application of cryosublimation: sublimation of frozen HTO solutions below equilibrium vapour pressure eliminates the possibility of isotope effects.We have studied several compounds, such as alkaline metal salts, humic substances, zeolites etc. and measured their capability to accumulate tritium from aqueous solutions through their hydrogen bonds. The most promising results were found for commercially available gelatine, which turned out to be a mixture of certain sugars and agar. More detailed studies are supposed to reveal, which of the two substances is responsible for the enrichment of tritium and the results will be presented. These experimental results will then be compared to calculations of zero point energies of tritiated and non-tritiated sugars, which will support future predictions of compounds, which are suitable for enrichment of tritium from aqueous solutions. THE PREPARATION OF 235MU TARGETS FOR 235U(N,N')235MU CROSS-SECTION MEASUREMENTS Evelyn M. Bond, Samuel Glover, David J. Vieira, Robert S. Rundberg, Gilbert Belier, Vincent Meot, Dominique Hynek, Yves Jansen. The 235mU isomer has a 26-minute half-life and a very low excitation energy of 77eV. Little is known about this isomer, especially its neutron-induced fission cross-section, which is of high interest to the Stockpile Stewardship program. Therefore a collaboration between Los Alamos National Laboratory, Lawrence Livermore National Laboratroy, and CEA at Bruyères le Châtel and Valduc has developed to measure the 235U(n,n')235mU cross-section. The target preparation for the calibration of the BIII detector and for the optimization of the sample preparation is described here. Two methods were used to collect samples of 235mU, which is formed by the alpha decay of 239Pu, for the calibration of the BIII detector. First, the 235mU was chemically separated from 239Pu by anion exchange chromatography and deposited on platinum foils using NH4Cl electrodeposition. The second method used an alpha recoil method in which 287 87 a target of 239Pu and 241Pu was prepared and 235mU and 237U were collected on salt plates, dissolved, and deposited on thin titanium foils using NH4SO4 electrodeposition. LA-UR-05-9299 288 PAPER CHROMATOGRAPHY FOR [186gRe]Re-HEDP RADIOCHEMICAL PURITY’ S EVALUATION IN BIOLOGICAL SAMPLES AFTER ADMINISTRATION S. Ridone, M. Bonardi, F. Groppi, A. Martinotti. University of Studies and INFN of Milan, Department of Physics, Laboratory of Radiochemistry LASA. [186gRe]Re-HEDP is a radiopharmaceutical used for pain palliation in bone metastases from various primary tumours. 186gRe has time decay (t1/2=90,64 hours) and β- energy (Emax=1,07 MeV) suitable to irradiate cancer and inflammatory cells, but it needs to be bound to disphosphonate salt to achieve good targeting. Two paper chromatography techniques (acetone or saline buffer with Whatman paper) were used to evaluate the solution‘s radiochemical purity, discriminating labelled [186gRe]Re-HEDP from [186gRe]ReO4- and [186gRe]ReO2. We decided to apply these methods also to biological samples (serum and urine) from patients treated with the radiopharmaceutical, in order to follow its bone-targeting and excretion. Samples‘ activity was measured with LSC Beta and HPGe Gamma Spectrometry. While blood samples were collected at preconceived time and chromatography was done immediately, it was difficult to do the same with urine samples depending on spontaneous urination of patients. Chromatographic analyses‘ delay from collection can invalidate results because urine environment decomposes radiopharmaceutical. We demonstrated that paper chromatographic elution with acetone and saline buffer can be used also for [186gRe]Re-HEDP radiochemical purity‘s determination in biological samples, if done immediately after collection. Following temporal distribution of activity a compartment model may help to understand the radiopharmaceutical‘ s biokinetics to optimise its administration. ANALYTICAL DETERMINATION WITH β- AND γSPECTROMETRY FOR RADIONUCLIDIC AND RADIOCHEMICAL PURITY OF [153Sm]Sm-EDTMP, A RADIOPHARMACEUTICAL IN BONE METASTASES PAIN PALLIATION S. Ridone, M. Bonardi, F. Groppi, A. Martinotti. For skeletal metastases metabolic radiotherapy is an alternative palliative care where radionuclids, alone or conjugated to biomolecules, are administered intravenously and act selectively on cancer cells. An effecive radiopharmaceutical is [153Sm]SmEDTMP, where 153Sm is labelled to a bone-targeting tetrakisphosphonate salt. Radionuclidic purity of [153Sm]Sm-EDTMP was determined on samples of injected radiopharmaceutical‘ s residual measured with HPGe -spectrometry. For 289 88 radiochemical purity it was analysed by paper chromatography with water/methanol/ammonia (25%) 4/2/0,2. Activity of paper‘ s shares was -spectrometry. Some urine samples from injected spectrometry identified in the radiopharmaceutical solution long life radionuclidic impurities (152Eu, 154Eu, 155Eu, 156Eu, 153Gd). Radiochromatographic analyses with LSC showed that impurities are enclosed in tetrakisphosphonate salt. As also urine‘ s analyses suggest, impurities seem to have a metabolic path similar to radiopharmaceutical. Measures indicated a high level of radionuclidic purity of [153Sm]SmEDTMP at the injection‘ s time, but long life impurities may be a problem in radioactive refuse‘ s disposal. Enclosure in tetrakisphosphonate salt can be a radiation source in bone tissue and it should investigate if a such constant radiation may explain bone metastases‘ arrest in some patients. 290 Measurement of Erbium Isotopes in Irradiated TRIGA Fuel: a proposed internal standard for determining the "degree of thermalization" of TRIGA reactors. Michael Michlik, James Sommers, Mary Adamic, Kevin Carney and Jeffrey Giglio. The potential to use erbium as a measure of the relative ratio of total neutrons to epithermal neutrons (similar to a cadmium ratio) has been proposed. The intent of this work is to examine if erbium isotopic ratios can be used to refine data input into reactor models, particularly with respect to fine tuning the reactor spectrum. The ratio can be used to help model fast to thermal ratios. Erbium isotopes were quantified in an irradiated fuel element from a Texas A&M Training Research Isotope General Atomics (TRIGA) reactor using thermal ionization mass spectrometry. The ratio of Erbium 167 to 168 was used to calculate a ratio that is similar to the cadmium ratio, but using a high energy cut off due to the large erbium resonance absorption integral as compared to the low energy cutoff of cadmium due to the 1/e absorption. The affect of the measurement precision on the determination is discussed, particularly with respect to utilizing the Er-170 isotope to predict beginning of life concentrations for the erbium poison. The possibility of using this ratio or similar ratios to refine reactor modeling efforts - by adjusting the reactor spectrum - for research reactor fuels that use burnable poisons is proposed. LINSSI - DATABASE FOR GAMMA-RAY SPECTROMETRY Pertti Aarnio1, Jarmo Ala-Heikkilä1, Arto Isolankila2, Antero Kuusi2, Mikael Moring2, Mika Nikkinen2, Teemu Siiskonen2, Harri Toivonen2, Kurt Ungar3, Weihua Zhang3; 1Helsinki University of Technology, Laboratory of Advanced Energy Systems; 2Radiation and Nuclear Safety Authority, STUK; 3Health Canada, Radiation Protection Bureau. LINSSI is an SQL database for HPGe gamma-ray spectrometry. It covers the whole measurement-analysis chain from sample collection to final analysis results. 291 89 LINSSI has been designed to support laboratories beginning from sample production or measurement; or performing spectrum analysis only. Multiple sample types are supported, including mobile sampling and measurement. In addition each sample can be split or combined any number of times. A sample may be measured multiple times and each measurement multiply analyzed as well. Measurement setups with detectors, shields, attenuators and source geometries can be defined in LINSSI. Full control of calibrations, their histories and backtracking of each calibration point to its corresponding analysis and calibration measurement is supported. The current version 1.1 of LINSSI contains 32 tables and 529 fields. It is operated in Linux using MySQL; however, the scripts are ODBC compliant. The experience with LINSSI consists of analyses of some 400,000 spectra, mostly air filter or mobile in-situ spectra. Currently UniSAMPO, Shaman and Aatami software packages support LINSSI, storing their analysis results automatically to the database. LINSSI specifications and scripts are made available to establish the database and to import or export data. For LINSSI documentation and some example scripts, see http://linssi.hut.fi/radphys/linssi/. 292 EVALUATION OF UNISAMPO-SHAMAN IN THE FIRST SYSTEMWIDE PERFORMANCE TEST OF THE CTBTO Pertti Aarnio1, Jarmo Ala-Heikkilä1, Timo Hakulinen2; 1Helsinki University of Technology, Laboratory of Advanced Energy Systems; 2Baryon Oy, Ltd. A set of 100 gamma-ray spectra with artificially added peaks of anthropogenic nuclides was utilized in the First System-Wide Performance Test (SPT1) of the Comprehensive Nuclear-Test-Ban Treaty Organization (CTBTO) in June 2005. The aim of this spectrum set was to evaluate the performance of different gamma-ray spectrum analysis software packages used by the organization itself and by the National Data Centres of member countries. This paper presents some findings when applying the UniSampo-Shaman software package in the analysis, with emphasis on the results from automated pipeline analysis. In summary, the performance of the system was very satisfactory: UniSampo-Shaman pipeline identified 199 nuclides of a total of 430 that were artificially added to these spectra. By inspection of the sizes of the missed peaks, only 4 nuclides were left unidentified because a peak above decision limit was left undetected. Additionally, an incorrect identification was made for 19 detected anthropogenic peaks. The artificial spectra of the SPT1 exercise provide a useful test set for performance tuning, since the set is comprised of cases for which the system has been designed. Although the observed deficiencies were few, measures were taken to improve the UniSampo-Shaman performance even further. EVALUATION OF CONTROL CHART METHODS FOR ON-LINE RADIATION MONITORING Lara D. Hughes and Timothy A. DeVol, Clemson University, Department of Environmental Engineering and Science. Several control chart methods are 293 90 presented for the evaluation of on-line sorptive scintillator flow-cells used for low-level environmental monitoring of radioactivity in aqueous solutions. The conventional method of comparing a sample count with a background value is not suitable for on-line count data, where it is necessary to detect small increasing trends in the count rate time series data. The control chart methods investigated are the 3-sigma chart, cumulative sum chart (CUSUM), and the exponentially weighted moving average (EWMA) chart. Each method triggers an alarm when the count rate exceeds a limit, which is based on the detector background. These control charts methods were applied to on-line data obtained from monitoring 99TcO4- in aqueous solutions and alarm trigger at a lower sorbed activity than it would be the case for the conventional method. The minimum detectable activity is 0.096 Bq (± 0.04 Bq) for the 3-sigma chart, 0.089 Bq (± 0.01 Bq) for CUSUM and 0.092 Bq (± 0.03 Bq) for the EWMA chart. The EWMA chart is best suited to predict the concentration of the sample for data collected after the trigger point. Based on the slope of the EWMA response it is possible to predict the solution concentration within 20% of the true value for concentration ranges of 0.5 - 5 Bq/L. 294 COMPARISON OF LIST MODE DATA ACQUISITON AND SHIFT REGISTER MEASUREMENTS USING THE LARGE EPITHERMAL NEUTRON MULTIPLICITY COUNTER (LEMC) Robert D. McElroy, Jr. and Stephen Croft, Canberra Industries Inc.. Neutron multiplicity analysis has been a valuable technique for safeguards measurements of plutonium oxide and mixed oxides. Historically, most of these measurements have been performed using shift register based electronics. The shift register data acquisition lacks a certain flexibility as the basic coincidence parameters (e.g. pre-delay, gate width, and long delay) must be fixed prior to the start of the measurement and the values may potentially, therefore, be sub optimal. List mode or time stamped data acquisition records the arrival time of each pulse thereby preserving the history of the pulse stream and allowing analysis and reanalysis using software analogs to the shift register circuit with adjustable parameters. Until recently, the data rates encountered in the assay of modest amounts of plutonium using highly efficient multiplicity counters were beyond the capacity of readily available personnal computers. The calibration of the Large Epithermal Neutron Multiplicity Counter (LEMC) for assay of plutonium scrap materials is used as a vehicle to compare the performance of the multiplicity shift register and a commercially available list mode acquisition module. ALPHA-CYCLOTRON PRODUCTION OF 211At/211gPo BY 209Bi (a,2n) REACTION S. Morzenti(a), M.L. Bonardi(a), F. Groppi(a),C. Zona(a), E. Persico(a), E. Menapace(b), Z.B. Alfassi(c), K. Abbas(d), U. Holzwarth(d), N. Gibson(d) (a) Università degli Studi di Milano and INFN-Milano, LASA, 295 91 Radiochemistry Laboratory, via F.lli Cervi 201, I-20090 Segrate, Milano, Italy, (b) ENEA, Division for Advanced Physical Technologies, Bologna, Italy, (c) Department Nuclear Engineering,Ben Gurion University, Beer Sheva, Israel, (d) IHCP, Institute for Health and Consumer Protection, JRCIspra, Varese, Italy. The direct production of 211At/211gPo by 209Bi(a,2n) reaction seems the most satisfactory method because it can be done in a medium energy cyclotron, leading to a high yield and low contamination by the radioisotopic impurity 210At. To check the procedure and to measure thick-target yields, irradiations of 209Bi targets were carried out at several a energies. The target thickness chosen was large enough to ascertain absorption of all particles with energy above 20 MeV because the calculated threshold for the reaction 209Bi(a,2n) is 20.72 MeV. Bi targets were irradiated at JRC-Ispra Cyclotron of EC, using a particles with energy higher than 28.61 MeV in order to produce also small amounts of the g-emitter 210At, via the 209Bi(a,3n) reaction. The presence of a small amount of 210At does facilitate radiochemical processing of irradiated target, because 211At/211gPo is an almost pure a emitter. The activity measured has confirmed that the irradiation conditions can be set up in order to obtain high activity of 211At and a wished amount of the 210At spike. The excitation functions for (a,2n) and (a,3n) reactions on 209Bi target were calculated using the EMPIRE-II computing system in collaboration with ENEA(Bologna). The results were compared to existing experimental data. 296 CONTAMINATION OF ALPHA-EMITTING IMPURITIES TO HIGH PURITY SILICA FROM PULBERIZING ALUMINA BALL Kil Yong Lee, Yoon Yeol Yoon, Soo Young Cho, Yongje Kim, Groundwater and Geothermal Division, KIGAM. The aims of this study were to develop NAA procedure of ultratrace alpha-emitting impurities in high purity silica, and to investigate contamination of the impurities from pulverizing alumina ball to the silica. Because the soft error of high precision electronic devices could be induced by the alpha-emitting impurities in raw materials. A new NAA procedure has been established using the HTS(hydraulic transfer system) irradiation facility which has been used to produce radioisotopes for industry or medicines, instead of PTS(pneumatic transfer system) irradiation facility which has been used in general NAA. For the minimization of contamination during sample preparation procedure, quartz burner was used with high purity sealing gas. And also, nitrogen flow system was used to stabilize and to minimize the unstable background gamma-spectra induced from rodon and its progeny nuclides in measuring chamber. The alpha-emitting impurities in high purity silica and pulverizing alumina ball were analyzed by using the new NAA procedures. More than three order of the impurities in high purity silica can be find in the alumina balls. The contamination rate of the impurities from alumina ball to the silica can be evaluated by this study. The abrasion rate of pulverizing alumina ball was about 2% weight during pulverization of silica. The contamination range of the impurities into silica from the alumina ball was about few ng/g. 92 298 ZINC UPTAKE IN SWINE INTESTINAL BRUSH BORDER MEMBRANE VESICLES USING A ZN-65/ZN-69M DUEL ISOTOPE EXPERIMENT C. E. Buff1, T. L. Veum2, and J. S. Morris1. 1University of Missouri Research Reactor Center, Columbia, MO 65211, USA. 2Department of Animal Sciences, University of Missouri-Columbia, Columbia, MO 65211, USA. . Supplemental zinc, typically as ZnO at twenty times greater than the NRC requirement, is routinely fed in large, confined, swine operations to alleviate physiological stress and enhance performance in weanling pigs. The mechanism by which zinc at these pharmacological intakes accomplishes this function is unknown; however, one consequence is clear-the concentration of Zn in the agricultural environment at undesirable levels. Hypothetically, organic forms of zinc, such as amino-acid complexes or polypeptides, are more efficiently absorbed than inorganic forms and their use would reduce the environmental impact from the eventual distribution of the waste products. However, lack of convincing evidence for this hypothesis and the substantially higher costs have prevented the displacement of ZnO by organic zinc supplements. To study zinc uptake in situ we have developed a model based on a multi-stage digestion followed by exposure to intestinal brush border membrane vesicles (BBMV) harvested from weanling pigs. In this paper we report on the feasibility of using a duel label (Zn-65 and Zn-69m) to simultaneously quantify the competitive uptake of Zn from co-existing organic and inorganic zinc supplements using our BBMV model. QUALITY CONTROL IN THE NEUTRON ACTIVATION ANALYSIS OF BIOLOGICAL MARKERS FOR SELENIUM IN EPIDEMIOLOGICAL INVESTIGATIONS J. Steven Morris1, Ruth Ann Ngwenyama1, James M. Guthrie1,2, John D. Brockman2, Vickie L. Spate1, J. David Robertson1,2. 1University of Missouri Research Reactor Center, Columbia, MO, USA 65211, 2University of Missouri-Columbia, Department of Chemistry, Columbia, MO, USA 65211.. Instrumental neutron activation analysis is being routinely used at the MURR to quantify selenium in prospectively collected biologic markers including blood sera and plasma, toenails, and fingernails. These specimens are typically collected from well-defined cohort populations participating in investigations assessing selenium intake and incidence of chronic disease endpoints. These epidemiological investigations, whether observational (case-control) or clinical (intervention), typically generate thousands of samples for analysis. Most adults, living in the U.S., have a daily dietary intake of selenium that exceeds the so-called nutritional requirement. Nevertheless, there exists evidence in support of the hypothesis that some individuals can benefit from a supra-nutritional (or pharmacological) selenium intake, generally achieved through supplementation, for optimal 299 93 protection against some chronic diseases. In addition to the known selenium determinants such as diet, supplementation, cigarette smoking and sex, suboptimal selenium status in the U.S. may be influenced by enzymatic polymorphisms, epigenetic factors, and the status of other nutrients. Consequently, misclassifications in the data set, including those due to analytical errors, must be minimized to observe what are often only subtle differences among cases and controls or treatment groups. The purpose of this paper is to assess potential analytical misclassification through evaluation of quality control results. 300 A MULTIPLE TIME-GATED SYSTEM FOR PULSED DIGITAL GAMMA-RAY SPECTROSCOPY H. Tan, S. Mitra, L. Wielopolski, A. Fallu-Labruyere, W. Hennig, Y. X. Chu, W. K. Warburton (XIA LLC, 8450 Central Ave, Newark, CA 94560 USA; Department of Environmental Sciences, Earth Systems Science Division, Brookhaven National Laboratory, Upton, NY 11973 USA). In conventional neutron activation analysis (NAA) using a pulsed neutron source, spectrum gating has been employed to segregate nuclear processes by acquiring gamma-ray spectra separately when the source was on (HIGH gate) and off (LOW gate). Advances in digital gamma-ray spectrometers recently allowed the concurrent acquisition of data by binning events in two separate spectra based on gate status. It was quickly realized that, for accurate, quantitative data analysis, it was also necessary to acquire accurate timing (live, clock, and dead time) and count rate information because counting rates varied not only between the on and off states, but within them as well. It became clear, therefore, that further information could be obtained to separate gamma-rays produced by different nuclear reactions (inelastic scattering, thermal neutron capture, delayed activation, etc.) by a time-resolved analysis that further subdivided the neutron source cycle. In this paper we present a gating system for time-resolved NAA capable of concurrently collecting data into up to 16 spectra from up to 8 user-defined time intervals during each of the HIGH gate and LOW gate periods, each with all required timing and count rate information. The architecture and operation of the system will be presented. OXYANION MATERIALS ANALYSES BY PROMPT GAMMA ACTIVATION ANALYSIS (PGAA) D.L. Perry, G. A. English, R. B. Firestone, K.-N. Leung. Prompt gamma activation analysis (PGAA) has been used to analyze oxyanion-containing materials that have multiple uses in both basic and applied research. The significance for the need for accurate, highly sensitive analyses for the materials is discussed in the context of both the materials themselves and trace elements that are exhibited in the parent solid matrices. Elemental analyses for a wide array of elements in the Periodic Table such as the ones in this work are of extreme value for a wide range of purposes, including gaining a knowledge of materials failures when they occur, modeling the 302 94 entire electronic, magnetic, and chemical properties of the constituent elements of the material, and assessing the purity of the materials as it relates to issues such as quality control. Both the elements and their compounds are useful for an extremely wide variety of applications in chemistry and materials science, including applications that are dependent on the elements' magnetic, electronic, and physical properties as well as their ability to form compounds and complexes and enter into synthetic chemical reaction schemes. Support for this work by the U. S. Department of Energy under Contract Number DE-AC02-05CH11231 is acknowledged. 303 CHARACTERIZATION OF LEGACY MATERIALS BY PROMPT GAMMA ACTIVATION ANALYSIS (PGAA) AND SHORT-LIVED NEUTRON ACTIVATION ANALYSIS (NAA) Dale L. Perry, Gerald A. English, Richard B. Firestone, Jani P. Reijonen, Ka-Ngo Leung (Lawrence Berkeley National Laboratory, Berkeley, CA 94720 USA), Glenn F. Garabedian (Lawrence Livermore National Laboratory, Livermore, CA 94550 USA), Gabor L. Molnar and Zsolt Revay (Institute for Isotope and Surface Chemistry, POB 77, Budapest H1525, Hungary). Much of the existing legacy inventory at national laboratory facilities also incorporates radioactivity, and, although radiological composition may be determined by various nuclear-analytical methods, most importantly, gamma spectroscopy, current methods of chemical characterization still require direct sample manipulation. Prompt Gamma Activation Analysis (PGAA) provides a 'single-shot,' in-situ, nondestructive method that provides a complete assay of all major entrained elemental constituents. Additionally , neutron activation analysis (NAA), using short-lived activation products, complements PGAA and is especially applicable when the NAA activation surpasses the PGAA in elemental sensitivity. The Lawrence Berkeley National Laboratory (LBNL) has developed a new miniature deuterium-deuterium (D+D) neutron generator that outputs ~ 4x109 neutrons/second. It is self-replenishing and low power and maximizes the use of monatomic D+ that, in turn, maximizes neutron intensity. The LBNL PGAA system also uses a recently updated prompt gamma library database and Hypermet software to convert the raw PGAA spectral data to accurate and precise qualitative and quantitative elemental results. This paper discusses the use of PGAA and short-lived NAA to characterize legacy materials at the Lawrence Berkeley National Laboratory (LBNL). Support for this work by the U. S. Department of Energy under Contract Number DE-AC02-05CH11231 is gratefully acknowledged. THE HIGH THROUGHPUT SCREENING OF SELECTIVE RADIONUCLIDE SEQUESTERING AGENTS AND THEIR INTEGRATION INTO A DECONTAMINATION TECHNOLOGY Edel M. Minogue, George J. Havrilla, Tammy P. Taylor, Deborah S. Ehler, Anthony K. Burrell, Mark E. Smith, William L. Earl. An effective high throughput double combinatorial screening technique is described for the 304 95 rapid selection of chelating agents for radioactive metal sequestration. While the binding of any specific cation can be determined by a systematic study or even combinatorial methods, it is a challenge to selectively extract a particular cation from complex mixtures, for example the debris after a radioactive dispersal device. We were interested in the selective extraction of radioactive metal cations from complex mixtures at a variety of pH values. In particular, the removal of cobalt and cesium from systems with high concentrations of competing metals such as Ca2+, Na+, Al3+, and Fe3+ as well as a number of possible organic cations and surfactants. The chelating agents of choice for our application were peptides and peptoids (Nsubstituted glycines). Peptoids are closely related to their natural peptide counterparts, but differ chemically in that their sidechains are appended to nitrogen atoms along the molecule's backbone, rather than to the α-carbons. Micro X-ray Fluorescence (MXRF) is the chosen method of analysis. It is a non-destructive method of analysis, which can detect elemental composition of a sample by measuring its characteristic X-ray emission wavelengths or energies. It is a tag-free, sensitive technique which in conjunction with the wide range of chemistry inherent in peptide and peptoid libraries (e.g. varying charge, length, hydrophobicity, aromaticity etc.), provides a rapid and quantitative means for screening chelator–ion binding. The method involves the screening of a bead-based library of either peptides or peptoids. The library is exposed to a nonradioactive isotope of the cation of interest and immobilized onto a microarray. The array is then screened and analyzed by MXRF enabling rapid identification of chelating agents. Initial experiments successfully identified peptide sequences that are selective for Co under certain binding conditions. This involved the screening of 8,400 sequences for cobalt binding in adverse environmental conditions containing possible interferences (e.g. Ca, Fe, Al, Cs, Ir). Once identified, the peptides or peptoids or combinations thereof, are integrated into a polymeric strippable coating. The coating is applied to a range of 137Cs- and 60Cocontaminated surfaces and on curing, the contamination is removed by peeling. The system has been tested on a variety of substrates with high success rates. 305 USING BETA/GAMMA COINCIDENCE SIGNATURES OF ENTRAINED RADIOACTIVE CONTAMINATES TO CALIBRATE RADIATION DETECTORS. J.I. McIntyre, M. Cooper, A. Day, J.C. Hayes, T. Heimbigner, C.W. Hubbard B.D. Milbrath, B. Schrom, and R. Suarez.Pacific Northwest National Laboratory, Richland, WA, 99354, USA. Calibrating the efficiency of radiation detectors in a field environment is difficult under most circumstances. Along with the difficulty of geometry effects increasing regulatory constraints are making it difficult to carry calibration radiation sources into the field environment. Energy calibration can usually be achieved for lightly shielded detectors via the naturally occurring background isotopes of 40K, and 238U and 232Th and their respective 96 daughter products. However the changing environmental background means that these same naturally occurring isotopes can not be used for efficiency calibrations and they may not always be present (radon and radon daughter products are a good example). To counter these problems a novel application of an existing scintillation detector makes it possible to reduce or eliminate the regulatory shipping requirements for an effective infield calibration source. Furthermore it will provides a near 100% beta gated gamma source in a small compact package. Lanthanum-Tri-Chloride has been touted as the new standard in large volume, room temperature, high resolution gamma-ray scintillation detection. The first commercial crystals suffered from high alpha contamination that was determined to be Ac-227 contamination (Milbrath et al, 2005). Subsequent crystal manufacturing managed to decrease this contamination to acceptable levels, but still left the dominate radioactive isotope 138La (t1/2 = 1.06 x 1011 yrs). In this paper we explore the effectiveness of using the beta-gamma coincidences properties of a 1.5‖x1.5‖ right cylinder LaCl3 detector to calibrate the energy and efficiency of a number of radiation detectors, (plastic, NaI(Tl), BGO, and HPGe). 306 A METHOD FOR REMOVING SURFACE CONTAMINATION ON ULTRA-PURE COPPER SPECTROMETER COMPONENTS C.E. Aalseth, A.R. Day, O.T. Farmer, E.W. Hoppe, T.W. Hossbach, J.I. McIntyre, H.S. Miley, A. Seifert, J.E. Smart, Pacific Northwest National Laboratory, Richland, WA, 99354, USA. The preparation of spectrometers for the lowest-level radiometric measurements requires materials of extreme radiopurity. Measurements of rare nuclear decays, e.g. neutrinoless doublebeta decay, can require bulk radiopurity reaching one micro-Becquerel per kilogram or less. When such extreme material purity is achieved, surface contamination, particularly solid daughters in the natural radon decay chains, can become the limiting background from the spectrometer itself. Highpurity copper is an important material for ultra-low-background spectrometers and thus is the focus of this work. A method for removing surface contamination at very low levels without attacking the bulk material is described. An assay method using a low-background proportional counter made of the material under examination is employed, and the resulting analysis of achievable surface contamination levels is presented. PNNL-SA47798 THE DESIGN OF A FAST NEUTRON PGAA FACILITY AT THE UNIVERSITY OF TEXAS AT AUSTIN S. M. Whitney (University of Texas), E. Alvarez (University of Texas), D. Haas (University of Texas), K. Jackman (University of Texas), S. Wilson (University of Texas), S. Biegalski Ph.D, P.E. (University of Texas). As part of a graduate engineering course titled ―Design of Nuclear Systems‖, graduate students at the University of Texas at Austin have designed a fast neutron filter system for the radial beam port of its MARK II TRIGA reactor. The course is designed to offer a small group of graduate students the chance 307 97 to formally propose and complete an engineering project during the semester. The project for the course was to design a fast neutron beam for fast neutron prompt-gamma activation analysis. A cadmium filter system is used to filter the incident neutron beam in order to leave a fast neutron beam that is used for the operation of a fast neutron PGAA facility. The filter consists of three separate pieces that can be altered to vary the incident neutron and gamma fluxes that exit the beam port. The fast neutron PGAA facility that utilizes the filtered beam has been modeled with the MonteCarlo code MCNP. The MCNP PGAA spectra of SRM standard materials are used for comparison to experimental PGAA results from previous thermal neutron beam analysis. 308 COMPLEXATION OF URANIUM (VI) WITH ACETOHYDROXAMIC ACID Peter Tkac, Radiation Center, Oregon State University, Brent Matteson, Department of Chemistry, Oregon State University, Jason Bruso, Department of Nuclear Engineering and Radiation Health Physics, Oregon State University, Alena Paulenova, Radiation Center, Oregon State University. In the UREX separation process, acetohydroxamic acid (AHA) is used to reduce and complex plutonium in order to decrease the distribution of Pu to the TBP-organic phase. However, the effect of AHA on the complexation and extraction equilibrium of uranium is not fully characterized. In this study, the extraction of U was performed from various initial concentrations of HNO3, lithium or sodium nitrate, and AHA. The results showed that, due to uranyl-AHA complex formation, the extraction of uranium to TBP slightly decreases when AHA is present in the feed aqueous solution. For the determination of distribution ratios, a combination of LSC and ICP-OES methods were used. UV-VIS spectrophotometry confirmed no reduction of uranium(VI) during the extraction experiment. Formation of orange-red uranyl-AHA complex was observed immediately after AHA addition. Intensity of the color decreases with increased acidity of aqueous phase because of a higher rate of hydrolysis of AHA. EXTRACTION OF TETRAVALENT METALS BY TBP: EFFECT OF NITRATE AND ACETOHYDROXAMIC ACID Peter Tkac, Radiation Center, Oregon State University, Jason Bruso, Department of Nuclear Engineering and Radiation Health Physics, Oregon State University, Brent Matteson, Department of Chemistry, Oregon State University, Sergey Lobach, Department of Nuclear Engineering and Radiation Health Physics, Oregon State University, Alena Paulenova, Radiation Center, Oregon State University. Acetohydroxamic acid (AHA) is added into UREX process solutions with the aim to reduce and complex plutonium decreasing the distribution of Pu to the TBP-organic phase. In this study, the extraction of tetravalent thorium, zirconium and cerium from a nitric acid matrix to 30% TBP in n-dodecane was investigated to evaluate the chemistry of tetravalent metals with AHA. Distribution ratios of metals were 309 98 measured in the presence of different initial concentrations of metal, nitric acid, lithium nitrate and acetohydroxamic acid in aqueous phase. Metal concentrations were measured by ICP-OES and/or LSC methods. When acetohydroxamic acid was present, a smaller distribution ratio was measured as a result of complexation or reduction of metals by AHA. In particular, the kinetics of reduction of Ce(IV) and the subsequent complexation of Ce(III) with AHA is very fast, while for the other metals studied, the complexation of the tetravalent species with AHA is the dominating process. Acetohydroxamic acid is hydrolyzed in acidic solutions; however, increase of HNO3 concentration causes larger distribution ratios of metals, and confirms a significant role of nitrate in the TBP-extraction mechanism. 310 Measuremets of presolar grain in meteorite using neutron activation analysis with multiparameter coincidence method Y. Hatsukawa, Y.Miyamoto, T. Hayakawa, Y. Toh, A. Kimura, M. Oshima, Japan Atomic Energy Agency. Method of multiparameter coincidence spectrometry based on gamma-gamma coincidence is widely used in the field of nuclear structure studies, and has produced many successful achievements. We developed a new technique of trace element analysis based on neutron activation analysis with coincident gamma-ray detection. In order to improve the low efficiency of coincident gamma-ray detection, an array of 16 Ge detectors with BGO Compton suppressors was used for this method. High sensitive trace element analyses without chemical separation were carried out by the combination of neutron activation analysis and the method of multiparameter coincidence spectroscopy. In the case of neutron activation analysis, measurements of gamma-rays from trace elements are strongly interfered by the gamma-rays from major elements, e.g., 24Na, 56Mn. So usually chemical separation processes are required to eliminate the major elements for determination of the trace elements. But using this method, we can detect very weak gamma rays from trace elements without chemical separations. In this study, we try to measure trace elements in presolar grains. Presolar grains are synthesis in the Super nova or Red giant, and found in the primitive meteorite. We obtained presolar grains from the Allende meteorite, and try to measure trace elements in the grains using this method. A CHERENKOV COUNTER FOR IN SITU MONITORING OF 90Sr IN GROUNDWATER R. L. Brodzinski, W. K. Hensley, D. V. Jordan, M. A. Maynard, R. C. Runkle, W. A. Sliger, J. E. Smart, and L. C. Todd, Pacific Northwest National Laboratory. Strontium-90 ground water contamination is an important issue at the U.S. Department of Energy's Hanford Site. To prevent 90Sr from entering the Columbia River, various remediation technologies have been applied in the past, and additional technologies are planned for future deployment. An in situ monitor, designed for deployment inside a monitoring well, provides near-real-time determination of the 90Sr 311 99 concentration in ground water. The measurement is based on the direct detection of the Cherenkov light generated in the water by the 90Y daughter beta-decay. The monitor is sensitive to 90Sr at concentrations below drinking water standards. Monte Carlo modeling was used to optimize the basic design with respect to size, shape, and composition of the detector, taking into consideration cost and reliability factors. Unforeseen construction problems will be discussed. Calibration and testing results of the as-built system will also be presented and will be compared to the modeling predictions. 312 DEVELOPMENT OF A BIPOLAR ELECTROLYSIS SYSTEM FOR TRITIUM ACCUMULATION IN HTO Joerg Aign, Birgit Wierczinski, Andreas Türler; Institute for Radiochemistry / Technical University of Munich. Enrichment of tritium in HTO solutions is done by two consecutive electrolysis steps. The main purpose of the first step is volume reduction of the sample solution in preferably short time and by lowest possible energy consumption. This is done by using a multiple bipolar electrolysis system. Depending on the initial volume of the sample and thus the resulting volume reduction factor, enrichment factors of about 6 to 7 are normally reached. To minimize the gaseous tritium release during this process to a negligible amount the sample solution is constantly cooled to a temperature of 0 to 4°C. In the second step the remaining HTO solution is transferred to a bipolar batch electrolysis cell for further enrichment. The enrichment process in this cell is based on the electrochemical permeation of hydrogen and its isotopes through a membrane that splits the cell in two compartments. First batch electrolysis experiments are carried out and results will be presented. GROSS ALPHA ACTIVITY DETERMINATION IN SALT-RICH WATERS USING EXTRACTION CHROMATOGRAPHY AND LSC S. HAPPELa, P. LETESSIERa, A. BOMBARDa, A.H. THAKKARb, E.P. HORWITZb; a:EICHROM EUROPE - Parc de Lormandière Bat. C, Campus de Ker Lann - 35170 Bruz - France, b: EICHROM TECHNOLOGIES 8205 S. CASS AVE- Darien, Il 60561 - USA. The determination of the gross alpha activity of salt-rich aequous samples, like mineral or waste waters, by Gas proportional counting (GPC) after evaporation shows two drawbacks due to dissolved solids found in these samples. Self absorption causes counting efficiency to decline to less than 10% when high amounts of solids are deposited; inhomogenous distribution of the solids on the support leads to low precision of the obtained gross alpha activity results. A resin was developped, which follows an alternative approach. Alpha-emmitters dissolved in the salt-rich water samples are extracted onto an extraction chromatographic resin. The gross alpha activity is then determined by direct measurement of the dried resin using a/b discrimination liquid scintillation counting. The resin contains a combination of several extractants supported on an inert polymeric substrate. It shows strong affinity for Actinides in the 313 100 tri-, tetra- and hexavalent oxidation state, as well as for Radium, out of acidified aqueous solutions, even when large amounts of Calcium, sulphate and other potential interferents are present in high concentrations. The method was validated for different matrices by analysing reference materials and spiked real samples. Results of good precision and accuracy were be obtained in counting times notably shorter than routinely used for gas proportional counting. 314 A MULTI-USER SERVER-BASED FRAMEWORK FOR SHAMAN GAMMA-RAY SPECTRUM IDENTIFICATION SOFTWARE Pertti Aarnio1, Jarmo Ala-Heikkilä1, Timo Hakulinen2; 1Helsinki University of Technology, Laboratory of Advanced Energy Systems; 2Baryon Oy, Ltd. We present a framework for a multi-user server-based installation of the Shaman gamma-ray spectrum identification software. It allows users to access centrally managed Shaman and UniSampo software packages in a laboratory-wide multi-workstation environment. The serverbased framework allows coordinated management of the software packages themselves as well as analysis parameter sets and analysis results either in a file system-based data vault or in an SQL-database based on the Linssi gamma-ray spectrometry database definition. Hierarchical management of analysis parameter sets allows full control of the individual analysis runs yet maintaining flexibility when analyzing a variety of sample types. Development of Multiple prompt gamma ray analysis Yosuke Toh, Masumi Oshima, Mitsuo Koizumi, Atsushi Kimura, Yuichi Hatsukawa. Multiple gamma ray detection method is widely used in nuclear physics experiments and known as coincidence method. In this method, when two or more gamma rays are detected coincidently by two or more gamma ray detectors, the event composed of pair of two prompt gamma rays is collected and added to the two dimensional spectrum which sets two axes as the energy value for every events. We applied the multiple gamma ray detection method to PGA, called MPGA. New Ge detector system for MPGA was constructed at JRR-3M C2 beam port in Japan Atomic Energy Agency (JAEA). Clover Ge detectors is used as prompt gamma ray detector. Each clover detector consists of 4 germanium (Ge) crystals surrounded by a Compton shield of bismuth germanium oxide crystals (BGO). Neutron beam is surrounded by enriched 6LiF tiles at sample position. ADC-DSP DAQ system and software were developed. The cross-talk effect of Clover detectors is improved by data sorting. The background reduction effects of replacement of Nitrogen, LiF tiles etc. were examined. Standard samples (NIST,NIES) were measured by MPGA. This study is supported by Industrial Technology Research Grant Program in 03A52003c from New Energy and Industrial Technology Development Organization (NEDO) of Japan. INDOOR RADON MEASUREMENT UNCERTAINTY 315 316 101 G.M. Reimer, Colorado School of Mines, Golden, CO 80401 USA. The measurement of indoor radon is not so straightforward as commonly perceived. Although standard, calibrated systems for radioactive counting and presumptive Poisson distributions will describe a concentration and standard deviation, often overlooked are the natural temporal and spatial concentration variations and the uncertainties introduced by different sample collection techniques. Because background concentrations are not constant, lower concentrations are especially subject to uncertainty. Various techniques typically used for indoor radon measurements and can be categorized as short term (days) or long term (months). The best approach is to use multiple measurements rather than using counting statistics for determining a standard deviation. In tests of selected devices, the variation ranged typically around 20 percent with an occasional "flyer" (four percent of yearly measurements) that could be as much as 500 percent higher. Overall, other tests of measurement devices found that 47 percent could give false positives at the US action level of 150 Bq/m3. Given this variability, as a general principle, it would be better to make multiple measurements and to select a value range for guidance when suggesting recommendations for action rather than to select a fixed number that is derived without a comprehensive consideration of the measurement uncertainties. 317 BERYLLIUM-7 ANALYSES IN SEAWATER BY LOW BACKGROUND GAMMA SPECTROSCOPY John E. Andrews1, Corinne Hartin2 and Ken O. Buesseler1. 1Woods Hole Oceanographic Institution, Woods Hole, Ma. 2Queens College, Queens, N.Y.. Oceanographers use the cosmogenic radionuclide 7Be(t1/2 53 days) as a tracer for atmospheric input and a conservative tracer of mixing in the open ocean. This paper elucidates a method for improving the analysis of 7Be from seawater. The scavenging efficiency of Fe(OH)3 for each sample is measured by ICP-MS using stable 9B as a yield monitor. Samples are gamma counted in a large diameter(28mm) well detector. The high purity germanium well detector is coupled with an active anti-coincidence cosmic guard to reduce the spectra background. The improved overall accuracy of the method and lower detection limit of the detector results in a lower volume of seawater needed for analyses. Results will be shown from a study of 7Be in the Sargasso Sea. The importance of a proper dead time setting in isotope ratio mass spectrometry Henrik Ramebäck (Swedish Research Defence Agency), Ulrika Nygren (Swedish Research Defence Agency), Michael Berglund (EC-JRC-IRMM), Douglas Baxter (Analytica). Precise and accurate isotope amount ratio measurement of plutonium and uranium is important e.g. in nuclear safeguards and nuclear forensics. One parameter that will limit the precision of isotope ratio measurements is the dead time of the detection system. Dead time determinations on mass spectrometric system with ion counting 319 102 detection can either be done using ratio measurement or via electronic measurement on individual components. Depending on the dead time of each component in the signal chain, the electronic determined dead time may not represent the true dead time of the total system. However, an artifical dead time in the pulse counting system that is long enough might yield a system dead time that can be represented by this artificial one. It is shown in this paper that a proper choice of an artificially introduced dead time will give a system that has the possibility to be charachterised to a much lower uncertainty compared to ratio-based dead time determinations. Ultimately, the impact of dead time uncertainty on the combined uncertainty of an isotope ratio measurement may be neglible even at very high count rates, >1 Mcps, i.e. implementing the dead time in a combined uncertainty calculation would not be necessary. 320 AGE DETERMINATION OF PLUTONIUM USING ICP-SFMS Ulrika Nygren1,2, Henrik Ramebäck1 and Calle Nilsson1, 1Swedish Defence Research Agency (FOI), Division of NBC Analysis, SE-901 82 Umeå, Sweden, 2Division of Chemistry, Luleå University of Technology, SE-971 87 Luleå, Sweden. The time since the last chemical separation, e.g, the age, of plutonium materials can be determined by analysing the isotope amount ratio of the plutonium isotopes and their daughter nuclides. In this paper, a method for age determination based on analysis of 241Pu/241Am and 240Pu/236Pu using ICP-SFMS is described. Separation of Pu and Am was done using solid phase extraction procedure including UTEVA, TEVA, TRU and Ln-resin. The procedure provided separation factors adequate for this purpose. Age determinations were performed on two plutonium reference material solutions, IRMM081 (239Pu) and IRMM083 (240Pu), on sediment from the Marshall islands (reference material IAEA367) and on Trinitite. The observed ages based on the 241Am/241Pu ratio corresponded well with the actual ages of all the materials. The ages derived from the 236U/240Pu ratio were in agreement for the IRMM materials, but for IAEA367 the determination of 236U was interfered from abundance sensitivity from 238U and for the Trinitite the determined age was biased due to formation of 236U in the detonation of the "Gadget". DETERMINATION OF 89Sr AND 90Sr IN PREPAREDNESS; OPTIMISATION OF TOTAL ANALYSIS TIME FOR MULTIPLE SAMPLES Annika Tovedal, Ulrika Nygren and Henrik Ramebäck, Swedish Defence Research Agency (FOI), Division of NBC Analysis, SE-901 82 Umeå, Sweden. In a radiological emergency situation a rapid determination of radiostrontium will be necessary. The required quantification levels will be relatively high which offers smaller sample sizes and shorter ingrowth and counting times. In this paper a rapid method for determination of 89Sr and 90Sr in fresh milk in emergency preparedness is presented. The method is based on microwave digestion of the milk, chemical separation of Sr, 321 103 ingrowth and separation of 90Y and Cherenkov measurements in a liquid scintillation counter. The method of microwave digestion was optimised by using multivariate modelling. In order to minimise the total analysis time a mathematical model was developed. The model parameters are the number of samples, time of ingrowth, counting time and detection limit. For a given number of samples the model predicts and minimises the analysis time by optimising the ingrowth and counting time in order to reach a detection limit fit for purpose. 322 A HIGHLY FLEXIBLE, MINIMUM DEAD TIME, DATA INTENSIVE ACQUISITION SYSTEM FOR CHARACTERIZATING LOW LEVEL DECAY EVENTS CONSTRUCTED WITH COMMERCIAL OFF-THE-SHELF HARDWARE Alan H. Band1, George A. Klouda2, and Stephen H. Pheiffer3, 1Electron and Optical Physics Division, 2Surface and Microanalysis Science Division, 3Center for Neutron Research, National Institute of Standards and Technology, Gaithersburg, MD 20899-8371, USA.. Since the early 1970's, NIST has maintained a low level (decay), multi-channel counting facility for measuring environmental samples and for pulse distribution studies tied to the behavior of proportional and Geiger-Müller detectors. Until 2002, pulses were time stamped and sorted using a TTL based logic interface (BNL) to discriminate coincidence, anticoincidence, guard and pulser events; to digitize the pulse height and rise time; to monitor specific characteristics of intra-channel and inter-channel events; and to measure microsecond timing between any two events. Over the course of time a PC-based waveform analyzer was added to gather the data from the original electronics and to digitize each pulse originating from the sample detector providing enhanced event characterization. Concern for the long-term reliability and serviceability of the BNL electronics motivated the development of a nextgeneration system using commercial off- the-shelf electronics. The only custom electronics in the entire system was a simple trigger board. The key components of the system are an SIS3300 8-channel, 12-bit, 100M sample/second, dual memory bank digitizer board and a 16-channel, GT657 Time Interval Analyzer. Both of these boards have either dual bank memory or deep FIFO buffers to allow the computer to readout previous event data while new data is being acquired. These data storage features allow one to operate with near zero dead time. With the addition of these precision acquisition units many of the event parameters previously determined by inflexible digital logic are now calculated in software. SEASONAL AEROSOL CONCENTRATIONS AT SUMMIT GREENLAND: ORGANIC CARBON, ELEMENTAL CARBON AND 14C ABUNDANCE OF TOTAL CARBON George A. Klouda1, Dustin Earnhardt2, Ann P. McNichol3, and Jack E. Dibb4, 1Surface and Microanalysis Science Division, National Institute of Standards and Technology, Gaithersburg, MD 20899-8371, USA, 2Old 323 104 Dominion University, Norfolk, VA 23529, 3National Ocean Sciences Accelerator Mass Spectrometry Facility, Woods Hole Oceanographic Institution, Woods Hole, MA 02543, USA, 4Climate Change Research Center, Institute for the Study of Earth, Oceans and Space, University of New Hampshire, Durham, New Hampshire 03824, USA.. A year-round observatory was established at Summit, Greenland in 1997 to study airsnow exchange processes. From August 2000 to February 2002, a high volume dichotomous aerosol sampler was deployed to collect airborne particulate material less than or equal to 2.5 micrometer aerodynamic diameter onto 90 mm diameter quartz-fiber filters. Weekly samples were collected from a clean air sector upwind from the campsite. Organic and elemental carbon concentrations were measured using a thermal-optical carbon analyzer. Aliquots of each filter were treated to stepwise heating first in an inert helium atmosphere up to 870° C then in a helium/oxygen atmosphere up to 910° C while monitoring the transmission of light through the filter using a diode laser. Throughout the process, carbon evolved and (or) combusted to CO2 is reduced to CH4 and quantified using a flame ionization detector. Any charring of organics is corrected for based on changes in the filter transmission. Select filters representing different seasons were analyzed for their 14C abundance of total carbon. Samples were combusted to CO2 in a closed quartz break seal, reduced to graphitic carbon and measured by accelerator mass spectrometry. 324 Rapid Analyses of Sr-90 on Savannah River Site High Cs-137 Radioactive Waste D. P. DiPrete, C. C. DiPrete, T. Eddy, N.E. Bibler (Savannah River National Laboratory), E. Holbert (Clemson University). As a result of accelerated waste cleanup efforts underway at the Savannah River Site, a need has been created to rapidly measure Sr-90 in high activity salt waste matrices. These matrices are high in Cs-137 (nominally as high as 1E10 dpm/g) but low in Sr-90, some cases having 6 to 7 orders of magnitude more Cs-137 than Sr90. The traditional method our laboratory used for analyzing Sr-90 in similar matrices was a solid phase extraction method based on Eichrom Technologies Inc.‘s Sr Resin. After a significant waiting period allowing ingrowth of the Y-90 daughter, Sr-90 activities were measured by liquid scintillation analyses of the interference free high beta energy region of Sr90‘s daughter Y-90. Stable strontium carrier recoveries were established using the Savannah River National Laboratory‘s Neutron Activation Analysis facility. Methodologies used to decrease the Sr-90 analyses turnaround times of the current Eichrom Sr resin extraction method will be discussed. NAA Applications at the Savannah River Site Using an Isotopic Neutron Source D. P. DiPrete, C. C. DiPrete, R. A. Sigg (Savannah River National Lab). Neutron activation analysis using low-flux neutron sources is used to address 325 105 important areas of applied interest in managing the Savannah River Site. Sensitivity needs for many of the applications are not severe; analyses are accomplished using a 20 mg 252Cf neutron activation analysis facility. Many radiochemical analyses at the Savannah River National Laboratory are made on various waste forms for the purpose of characterizing the radionuclide distributions for the waste receiving facilities. The non-routine nature of these waste samples analyzed by our laboratory often dictates the use of separations that are traced on a sample by sample basis. Following radiochemical separation with stable carrier addition, radiochemical yields for a number of these separations are determined by neutron activation of the stable carrier. For some elements, no suitable stable carriers exist. In some of these cases, the source has been used to generate radioactive tracers to yield these separations. Modern analytical methods such as ICP-mass spectrometry provide sensitivities for many elements that can not be matched by NAA using isotopic sources. Because NAA allows analysis of bulk samples, it offers strong advantages for samples in difficult-to-digest matrices when its sensitivity is sufficient. Examples at SRS include assuring chloride concentrations in materials that may be used with stainless steels meet technical specifications. 326 TRANSURANIUM ELEMENTS AND FISSION PRODUCTS IN FUEL CHANNELS OF UNIT 2 OF CHERNOBYL NUCLEAR POWER PLANT Andrey Berlizov1, Igor Malyuk1, Anatoly Sajeniuok1, Volodymyr Tryshyn1, Volodymyr Petrov2, Andrey Savin2, Said Abousahl3, Gert Rasmussen3, Ilkham Sadikov4, Mukhmammad Salimov4, 1INR NASU, Institute for Nuclear Research, Kiev, Ukraine, 2SSE Chernobyl Nuclear Power Plant, Slavutych, Ukraine, 3EC-JRC-ITU, Institute for Transuranium Elements, Karlsruhe, Germany, 4INP AS RUz, Institute of Nuclear Physics, Tashkent, Uzbekistan. Theoretical estimations show that for NPPs with RBMK reactors by the end of operating period 85-90% of total activity of a reactor facility (excluding nuclear fuel) are incorporated in the fuel channel pipes (FCP). According to the calculation results, the main radionuclides, forming the activity of FCPs 10-20 years after reactor shutdown, are 3H, 14C, 36Cl, 39Ar, 41Ca, 55Fe, 60Co, 59Ni, 63Ni, 93Zr, 93mNb, 94Nb; all are due to the activation of either matrix (Zr - 2.5 wt.% Nb alloy) or impurities. Besides the indicated radionuclides, presence of Pu, Am and Cm isotopes as well as fission products, such as 137Cs and 90Sr, could be expected as a result of loss of containment of fuel elements during reactor operating and possible U and Th impurity in the FCP material. FCP samples were taken at different heights of 5 fuel channels within the reactor core of power unit 2 of the Chernobyl NPP, being under the initial stage of decommissioning. The samples were subject to gamma-spectrometry and radiochemical analysis for the content of 90Sr, 137Cs, 238Pu, 239+240Pu, 241Am and 244Cm. It was found that specific activity of 90Sr varies from 400 Bq/g to 5500 Bq/g, 137Cs - from 700 Bq/g to 13000 Bq/g, 238Pu - form 106 30 Bq/g to 5100 Bq/g, 239+240Pu - from 15 Bq/g to 140 Bq/g, 241Am from 30 Bq/g to 350 Bq/g, 244Cm - from 2 Bq/g to 2100 Bq/g. To elucidate the origin of the revealed contamination, samples of source FCP material were subject to RNAA and ICP-MS impurity analysis, as well as relevant transuranium element buildup calculations were performed with ORIGEN and NAAPRO codes. 327 BLACK POPLAR (Populus nigra L.) BARK AS AN ALTERNATIVE INDICATOR OF URBAN AIR POLLUTION BY HEAVY METALS Andrey Berlizov1, Oleg Blum2, Roy Filby3, Igor Malyuk1, Volodymyr Tryshyn1, Yulian Tyutyunnik4, 1INR NASU, Institute for Nuclear Research, Kiev, Ukraine, 2NBG NASU, National Botanical Garden, Kiev, Ukraine, 3WSU, Washington State University, Pullman, USA, 4National Taras Shevchenko University of Kiev, Kiev, Ukraine. Application of traditional biological indicators, such as lichens and mosses, for air pollution monitoring in urban and industrial areas frequently encounters difficulties connected with lack or scarcity of biological material of indicator species in sampling points. Because of this fact the search of alternative biological indicators is becoming especially important. Relevance of poplar tree bark for its application in the urban air pollution monitoring studies was examined. For this purpose a representative set of pairs of "bark - lichen" samples were simultaneously collected in the same points within the Kiev city agglomeration. Chosen based on the urban landscape non-regular network approach the locations of sampling points were characterized by different nature of the air pollution both in qualitative and quantitative respects. The performance of bark (2-3 mm upper layer) was tested against two species of lichens - Xanthoria parietina (L.) Th. Fr. and Physcia adscendens (Fr.) H. Oliver, which are typical for the region under investigation. A combination of conventional and epithermal INAA was applied to determine concentrations of 40 minor and trace elements in collected samples. The obtained analytical data were statistically processed with the use of nonparametric tests, such as sign test and Kendall coefficient. It was shown that for the majority of the elements determined there exists a good correlation between their contents in bark and lichens. Bark turned out to be not inferior to both lichens studied in heavy metal accumulation capability. Only with respect to chlorine bark revealed much less (7-8 times lower) accumulation capability. While uptake of such elements as Au, Ba, Ca, Co, Cu, I, Mn, Nd, Ni, Sb, Sr, V, Zn by bark was found to be reliably higher than that by lichens by a factor of 2 to the lowest. The report will discuss the results of statistical processing of the obtained analytical data as well as peculiarities of bark sample collection, pre-irradiation treatment and elemental analysis with the use of INAA method. 328 A DYNAMIC LINK LIBRARY FOR CALCULATING TRUECOINCIDENCE SUMMING CORRECTION FACTORS 107 Andrey Berlizov, INR NASU, Institute for Nuclear Research, Kiev, Ukraine. A DLL was created for calculating true-coincidence correction factors in gamma- and X-ray spectrometry applications. Calculations are done by Monte-Carlo approach on the basis of the Evaluated Nuclear Structure Data File ENSDF/2, supplemented by the yields of X-rays of K- and L-series. In calculations the emission of cascade gammas, as well as g-X, g-g511 and XX coincidences are appropriately taken into account. A set of measurement geometries implemented includes combinations of coaxial, planar, broad energy and well-type detectors with point, surface, cylinder and Marinelli beaker sources. Dimensions and materials of both detector and source are user-specifiable. Together with the true-coincidence correction factors the full-energy-peak efficiencies are calculated and reported for all gammas and X-rays emitted by a requested radionuclide. The DLL was tested by comparing its results with experimental data and results of the analogous calculations with help of MCNP code. 329 TALSPEAK SOLVENT EXTRACTION PROCESS FOR ACTINIDE/LANTHANIDE SEPARATION Delbert L. Bowers, Artem V. Gelis, Allen J. Bakel, Candido Pereira, Monica C. Regalbuto, George F. Vandergrift, and James J. Laidler, Chemical Engineering Division, Argonne National Laboratory, Argonne, IL. Separations of actinides from lanthanides are a subject of great importance in closing the fuel cycle. Currently the Advanced Fuel Cycle Initiative (AFCI) is developing technologies for this purpose. During the summer of 2005 a process demonstration of the TALSPEAK process was conducted using spent fuel. This process utilized as a lanthanides extractant HDEHP in Dodecane. The pH was controlled using DTPA/Lactate buffer. The demonstration was conducted using centrifugal contactors in a hot cell facility at Argonne National Laboratory. The analytical techniques used to analyze the results of this test will be presented. Research funded by U.S. Department of Energy, Office of Nuclear Energy, Science and Technology, under Contract W-31-109-Eng-38. DETERMINATION OF ACTINIDE AND FISSION-PRODUCT ISOTOPES IN VERY-HIGH-BURNUP SPENT NUCLEAR FUEL V.S. Sullivan, D.L. Bowers, M.A. Clark, D.G. Graczyk, Y. Tsai, W.E. Streets and M.H. Vander Pol (Chemical Engineering Division) and M.C. Billone (Energy Technology Division) Argonne National Laboratory, Argonne, IL 60439. Interest among nuclear power producers has grown over the past few decades in higher utilization of nuclear fuel, which translates to achieving higher burnup (a measure of the number of atoms that underwent fission). Computer codes that predict the time-dependent nuclide inventory in spent nuclear fuels, as needed for safety and licensing evaluations, have been validated for burnup levels up to about 40 GWd/MTU. Experimental isotope-assay data for higher-burnup fuels are relatively rare but are of considerable interest for benchmarking code performance beyond this range, 330 108 particularly in relation to the concept of "burnup credit," an allowance in safety analysis calculations for decreased reactivity in the fuel as a result of actinide depletion and a presence of neutron-absorbing irradiation products (poisons) that reduce the fuel's ability to achieve criticality. A wide array of actinide and fission-product isotopes in light-water-reactor fuel specimens having >70 GWd/MTU burnup were measured. Uranium, plutonium, and neodymium isotopes were measured with isotope-dilution methods to provide high accuracy for these key nuclides. Solutions of the raw fuel and separated fractions were also analyzed by thermal-ionization and inductively-coupled-plasma mass spectrometry, alpha counting, and gamma counting. With relatively few operations, data were made available for 75 isotopes. Some of the burnup-credit isotopes we measured (103Rh, 95Mo, 101Ru) have not been reported previously for high-burnup fuels. Work supported by the U.S. Department of Energy under Contract W-31-109-Eng38. 331 The Preparation of a Cm-245 Chemical Yield Tracer Jerome, S.M., Pearce, A.K. and McLoughlin, J., NPL. There is anecdotal evidence to suggest that the chemical yield of Americium and Curium may differ in radiochemical analysis. In this paper, we describe the preparation of a low-level standard of Cm-245 from an aged source of Cf-249. The separation was effected by cation exchange, using 2-hydroxy-2-methylpropanoic acid (a-hydroxy-isobutyric acid or a-HIBA) at controlled pH, Cf249 being eluted before the Cm-245 daughter. The purity of the Cm-245 was measured by alpha particle spectrometry and gamma spectrometry. The standardisation of the purified Cm-245 was achieved by liquid scintillation counting and the paper describes the theoretical basis for this measurement. The low-level standards thus produced are suitable for both work with aparticle spectrometry and mass spectrometry. Trend Analysis Techniques for Quality Control Measurements in Radionuclide Assay Jerome, S.M., NPL. The use of quality control chart techniques in many different fields of human activity is well established, and is the subject of a series of ISO standards. Furthermore, the use quality control techniques is a specific requirement of ISO 17025:2005. However, the common useage of such charts is to simply use ‗2s warning limits‘ and ‗3s action limits‘ to monitor the on-going control of measurements with little or no trend analysis. The use of trend analysis rules is described and illustrated with examples from measurements made at NPL with ionization chambers, liquid scintillation counters and g-spectrometers. The use of Cumulative Summation (CuSum) techniques will also be described, with recommendations of how these techniques can be used to enhance the quality of secondary standard measurements. On the integrated decay and ingrowth equations used in the 332 333 109 measurement of radioactive decay families: Uncertainties Jerome, S.M, NPL. In a previous paper(1), the general solution for time integrated decay and ingrowth equations(2) was derived. In this paper, a theoretical analysis of the uncertainties arising from the these equations is presented, and the specific case for simple parent-daughter systems is examined.This theoretical treatment will enable a better estimate of the uncertainties associated with the ingrowth of a daughter radionuclide formed from the decay of a radioactive parent. It also will allow a better estimate of the uncertainty on the time when only the parent radionuclide was present, based on activity ratio measurements. (1) Harms, A.V. and Jerome S.M., ‗On the integrated decay and ingrowth equations used in the measurement of radioactive decay families: the general solution‘, Appl. Radiat. Isot., 61, (2004), 367–372 (2) Bateman, H., ‗The solution of a system of differential equations, occurring in the theory of radioactive decay‘, Proc. Camb. Philos. Soc., 15, (1910), 423–427 334 Accreditation to ISO 17025:2005 for a National Metrology Institute Jerome, S.M., NPL. In the mid 1990s, the National Physical Laboratory (NPL) took the decisiion to seek external accreditation to the then UK national accreditation standard (M10, M10 supplement and M11) through the NPL's National Measurement Accreditation Service (NAMAS). This paper details the reasoning behind that initial decision and, in particular, how this impinged on the day-to-day activities of the NPL's Radioactivity Metrology Group (RMG). In the intervening decade, the accreditation standard has changed considerably; accreditation is now to the international standards ISO 9001:2000 (Quality management systems — Requirements) and ISO 17025:2005 (General requirements for the competence of testing and calibration laboratories); accreditation is now carried out by a wholly separate sucessor organisation to NAMAS, the United Kingdom Accreditation Service (UKAS). The RMG's scope of accreditation has also changed considerably over the years and this will be discussed with a forward look over the next decade. The performance of UK laboratories in proficiency tests for the measurement of Am-241 Jerome, S.M., Harms, A.V., Dean, J.C.J. and Gilligan, C.R.D., NPL. Since the late 1980s, the Radioactivity Metrology Group (RMG) of the UK National Physical Laboratory (NPL) has organised sesquiennial environmental proficiency tests for a range of radionuclides including fission products, activation products of reactor construction materials and fuel activation products. This has, over the years, grown to encompass a number of actinoid radionuclides and this has included Am-241. Americium-241 is of environmental concern from direct release to the environment via fallout and from fuel reprocessing activities; a second source term is the generation of Am-241 in the decay of Pu-241. Furthermore, this nuclide is interesting, since it can be measured by employing several very different measurement 335 110 strategies; a-particle specrometry, g-ray spectrometry, liquid scintillation counting and mass spectrometry. The data gathered by NPL to date allows the comparison of these different techniques and how laboratories employing them fared in the proficiency test exercises NPL has conducted. 336 Radionuclide Metrology developments at the UK's National Physical Laboratory since MARC-VI Jerome, S.M. and Judge, S.M., NPL. The Radioactivity Metrology Group (RMG) at the UK's National Physical Laboratory (NPL) has been involved in the standardisation of radioactivity since receipt of the first British National Radium standard in 1912. Much has changed since that time and NPL is now operated by SERCo Ltd on behalf of the Department of Trade and Industry. Since the last MARC meeting, there have been a number of significant developments at NPL, one of which was to finally consign the British National Radium standards to a waste repository. The science of the group has been advanced in several different areas; the development of an organically bound tritium standard; the standardisation of both F-18 and Tc99m and their subsequent submission to the BIPM reference ionsation chamber in Paris; development of new fission product separation techniques; generation of syringe calibration factors for medically important radionculides; the validation of Cerenkov counting techniques in support of radionuclide metrology. This poster will summarise these and other developments with a forward look for future work. DETERMINATION OF As(III) and As(V) IN DRINKING WATER BY SOLID PHASE EXTRACTION AND NEUTRON ACTIVATION Wilber Menendez Sanchez, Blaine Zwicker, A. Chatt, SLOWPOKE-2 Facility, Trace Analysis Research Centre, Department of Chemistry, Dalhousie University, Halifax, Nova Scotia, B3H 4J3, Canada. Arsenic speciation in drinking water has become an interesting field of research due to the chronic toxic effects associated with the presence of even low levels inorganic arsenic compounds in groundwater and other water reservoirs. Neutron activation analysis (NAA) has been combined with solid phase extraction (SPE) and coprecipitation methods to achieve speciation analysis of two important inorganic arsenic species, namely As(III), As(V). Arsenic(V), an anion in weak acidic and neutral media, is separated and concentrated onto an anion exchange cartridge while As(III) remains in the effluent in its neutral form. Bismuth sulfide coprecipitation of the effluent provides quantitative preconcentration of As(III). Arsenic (V) is quantitatively eluted with 1M nitric acid after a two-step column cleaning with distilled deionized water and 0.1M acetic acid solution. This simple and easy method has been applied to the analysis of water reference materials as well as natural water samples. The detection limits are 2.9 ng/mL for As(V), 2.0 ng/mL for As(III) and 43 ng/mL for total arsenic using a low-flux SLOWPOKE reactor. 337 111 338 COMPARISON OF TEVA RESIN WITH NEW SOLID EXTRACTANT CONTAINING ALIQUAT 336 FOR DETERMINATION OF RENIUM USING RADIOCHEMICAL NEUTRON ACTIVATION ANALYSIS Lučaníková Mária1,2, Kučera Jan2,3, Šebesta Ferdinand3 1Faculty of Nuclear Sciences and Physical Engineering CTU, Břehová 7, 115 19 Prague 1, Czech Republic 2Nuclear Physics Institute ASCR , 250 68 Řež near Prague, Czech Republic 3Centre for Radiochemistry and Radiation Chemistry CTU, Břehová 7, 115 19 Prague 1, Czech Republic. Extraction chromatography (EXC) belongs to techniques for separation and preconcentration of radionuclides for analytical purposes, including radiochemical neutron activation analysis (RNAA). The new solid extractant was prepared by incorporation of the active component liquid trialkylmethylammonium chloride (Aliquat 336) in an inert matrix made of modified polyacrylonitrile. The active component of this solid extractant and Eichrom´s TEVA Resin is identical and both materials have properties similar to those of typical strong base anion exchange resins and show high selectivity to ReO4- at a lower concentration of nitric and hydrochloric acid. The properties of both materials, such as selectivity (distribution coefficient, decontamination factors for 24Na, 42K and 82Br) and retention capacity as functions of pH, flow rate, etc. were tested and optimized in column experiments by using radiotracer of Re. Results of the RNAA procedure for determination of Re in some biological and environmental materials using the new material and TEVA Resin are presented and compared. 339 QUANTITATIVE GAMMA-RAY SPECTROSCOPY Henry C. Griffin, Dept. of Chemistry, Univ. of Michigan, Ann Arbor. Accurate assays of radioactive materials by gamma-ray spectroscopy depend on many factors, the most obvious being accurate gamma-ray intensities. We have used radiochemical methods to prepare pure samples of actinides. One portion of each of these samples was used to measure disintegration rates (generally by liquid scintillation counting), and the remainder was used to obtain count rates of specific gamma rays in a well-characterized HPGe spectrometer. Particular attention has been given to efficiencies for detecting low energy beta and photon radiations. These methods will be illustrated by results from studies of Np isotopes (237, 238, and 239) and relevant genetic relations. The Nuclear Workforce - Matching Training and Demand Alice C. Mignerey, University of Maryland. This paper will analyze current available data on nuclear education and correlate the results with projections of the nuclear workforce which will be required over the coming years. Many have predicted that there will be a crisis in the training of nuclear scientists (chemists and physicists) with the great reduction in representation of this discipline on Chemistry and Physics faculties in the United States. 340 112 The Nuclear Chemistry Summer School has been instrumental in providing some of the training and exposure, but there is still a need for graduate education in Nuclear Science. Specific emphasis will be placed on the situation in Nuclear Chemistry. Can the increasing gap between prrduction and demand be filled by the Nuclear Physics Community? What are the projections for the field of Nuclear Science as a whole over the coming decade and how are current research funding profiles impacting education? These are a few of the issues which will be addressed. 342 Actinide Targets for Neutron Cross Section Measurements J. D. Baker & C. A. McGrath, INL; T.S. Hill, LANL. The Advanced Fuel Cycle Initiative (AFCI) and the Generation IV Reactor Initiative have demonstrated a lack of detailed neutron cross-sections for certain "minor" actinides, those other than the most common (235U, 238U, and 239Pu). For some closed-fuel-cycle reactor designs more than 50% of reactivity will, at some point, be derived from ―minor‖ actinides that currently have poorly known (n,g) and (n,f) cross sections. A program of measurements under AFCI has begun to correct this. One of the initial hurdles has been to produce well-characterized, highly isotopically enriched, and chemically pure actinide targets on thin backings. Using a combination of resurrected techniques and new developments, we have made a series of targets including highly enriched 240Pu, and 242Pu. Thus far, we have electrodeposited these actinide targets. In the future, we plan to study reductive distillation to achieve homogeneous, adherent targets on thin metal foils and polymer backings. As we move forward, separated isotopes become scarcer, and safety concerns become greater. The chemical purification and electodeposition techniques will be described. ENHANCING ACADEMIC AND RESEARCH PROGRAMS OF NUCLEAR AND RADIOCHEMISTRY IN MIT NUCLEAR REACTOR LABORATORY Xudong Huang, Massachusetts General Hospital/Harvard Medical School, MIT Nuclear Reactor Laboratory; Lin-wen Hu, MIT Nuclear Reactor Laboratory. Nuclear and radiochemistry have become neglected disciplines, with a shrinking talent pool of nuclear and radiochemists globally. Many factors such as outmoded academic and research programs and narrow disciplinary definitions have contributed to this declining trend. To enhance the academic and research programs of nuclear and radiochemistry and enrich their disciplinary contents, the MIT Nuclear Reactor Laboratory has embarked on strengthening its nuclear and radiochemistry research. Specifically, we will pursue the following novel applications of nuclear and radiochemistry in drug development and biomedical research: (i) 14C- and 3H-labeling of drug leads: We are building a synthetic radiopharmaceutical chemistry facility. These radiolabeled lead compounds will be used to generate their preliminary ADMET (absorption, distribution, metabolism, excretion, and toxicity) profile in their preclinical microdosing studies using 343 113 ultra-sensitive accelerator mass spectrometry (AMS). This emerging drug development strategy is the so-called Phase Zero approach that means to be more cost-effective. (ii) Retrospective cell age determination using 14Cdating and AMS methods: Recent data strongly indicate that 14C concentrations in genomic DNA parallel atmospheric levels of 14C mainly from nuclear weapon testing in mid 1950s and early 1960s. Based on this, a retrospective cell birth dating strategy using 14C-dating and AMS methods has recently emerged. We will use it to measure cell turnover in human under normal and diseased conditions such as stem cell, Alzheimer's disease, etc. (iii) Tumor-targeted nanoparticles containing 10B for Boron Neutron Capture Therapy (BNCT): We will prepare novel nanoparticles containing poly 10B atoms and ligands (such as biotin) targeting cancer cells with highly expressed specific ligand receptors (such as biotin receptors) in their surface. These research programs can also be an educational platform to attract and train a new generation of nuclear and radiochemists with a repertoire of diverse research skill sets. We believe that our endeavor may provide some degree of remediation and image improvement for the dwindling disciplines- nuclear and radiochemistry that have contributed significantly to human civilization and welfare. 344 INITIAL STAGES OF THE DEVELOPMENT OF A UK PRIMARY STANDARD FOR POSITRON EMITTERS IN GAS Maria Marouli*,**, Julian Dean**, N. M. Spyrou*, *University of Surrey, School of Electronics and Physical Sciences, Physics Department, Guildford, Surrey GU2 7XH, UK, ** National Physical Laboratory, F6,Radioactivity Group, Quality of Life Division ,Hampton Road, Teddington, Middlesex, U.K. TW11 0LW. Positron Emission Tomography (PET) is a molecular imaging modality which has been used as a clinical tool for the last 15 years. Its use is expanding at a high rate with the development of combined PET/CT modalities offering several advantages. The positron-emitting radionuclides that are used in PET imaging are produced in cyclotrons. For positron emitters in the gaseous phase, the total activity released during the production of the positron emitter in a typical run ranges from tens to a few hundreds of MBq which in the case of a target failure can be of the order of a few GBq. Although there is specialized instrumentation manufactured by several companies and designed for monitoring releases of gaseous positron emitters, there is no calibration facility for such instruments at present. A UK primary standard and monitor calibration service are needed to ensure that such measurements are accurate and traceable. A system of gas flow proportional counters, already established at the National Physical Laboratory (NPL) for the standardization of -emitting gases, will be used as the basis of the primary standard; however, the short half-lives of the radionuclides used in PET and the differing physical properties of positrons and electrons will need to be taken into account and the gas standardisation procedure will have to be modified accordingly. Adjustment and possible modification of the current gas-handling system is being investigated and the 114 PENELOPE Monte Carlo code is to be used to model the response of the counters to positron emitters. The model will be verified in the longer term via comparison with other counting systems previously calibrated for positron emitters. Other means of calibrating monitors for positron emitters in gas are being considered. 345 IMPROVEMENT OF DETECTION LIMITS FOR GAMMA-RAY EMITTING RADIONUCLIDES IN NATURALLY OCCURRING RADIOACTIVE MATERIALS BY A COMPTON SUPPRESSION SPECTROMETRY SYSTEM Sonia E. Hevia, A. Chatt, SLOWPOKE-2 Facility, Trace Analysis Research Centre, Department of Chemistry, Dalhousie University, Halifax, Nova Scotia, B3H 4J3, Canada . The determination of very low activities from naturally occurring radioactive materials (NORM) by gamma-ray spectrometry requires the use of detection systems with minimum background activity. In our laboratory, we have combined a lead shield around an HPGe coaxial detector and a Compton suppression system to lower the background activity. This detector has a relative efficiency of 25% and a resolution of 2.0 keV at the 1332-keV photopeak of 60-Co. The HPGe is surrounded by a 10‖ x 10‖ NaI(Tl) annulus and an additional 3‖x 3‖ NaI(Tl) plug on top of the annulus. The peak-to-Compton plateau ratio of this system is 590 at the 1332-keV peak of 60-Co. The external background was evaluated by first counting the empty detector for 24 h without the lead shielding in conventional mode (A). Then the same procedure was repeated with the lead shield (B). A third counting was done using the Compton suppression system and the Pb shield (C). A background reduction factor of approximately 3 was obtained by comparing the spectra collected using the systems (A) and (B). When the conventional and the Compton suppression systems with Pb shielding (i.e. B and C) were compared, the background reduction factor was about 10. The detection system was calibrated using multiple gamma-ray sources (Amersham International) including different geometric shapes and volumes to simulate the sample containers. It was then possible to identify the following nuclides in drinking water, well water, spring water, oyster and mussel samples: (i) 234-Th, 230-Th, 214-Pb, and 214-Bi belonging to the 238-U decay series; (ii) 235-U, 231-Pa, and 227-Th of 235-U decay series; and (iii) 228-Ac, 228Th, 212-Pb, and 212-Bi of the 232-Th decay series. The sources of uncertainty related to these measurements were evaluated and the associated expanded uncertainty quantified. A comparison of pulser-stablised analog spectrometers and digital spectrometers C.A. McGrath, R. J. Gehrke, J. K. Hartewell, Idaho National Laboratory. We have conducted a comparison of several digital-signal-processor based spectrometers with the pulser-stabilized analog spectrometers currently in used in our radioanalytical laboratories. We have studied the stability, 346 115 spectral quality, rate-handling, and ease of use. Results will be shown for several different digital systems compared to an analog spectrometer. 347 DELAYED-NEUTRON ACTIVATION ANALYSIS FOR DETERMINING TRACE FISSIONABLES AT NIST Richard M. Lindstrom, DennisE. Brady, and R. Gregory Downing, National Institute of Standards and Technology, Gaithersburg, Maryland. Passive detection of clandestine fissionable materials is technically challenging, because U-235 and Pu-239 emit little radiation and that radiation is easily shielded. A great deal of effort and ingenuity are being put into active methods of detecting kilogram quantities of fissionables in situ, but the apparatus for neutron or photon probes and detectors is bulky, expensive, and requires radiation protection measures. A complementary forensic method involves the laboratory analysis of wipes to detect traces of fissionable material that have been deposited during handling. This approach has been used effectively, for instance by IAEA inspectors in Iraq. Delayedneutron activation analysis (DNAA) is a well-tested method, specific for those nuclides that fission with thermal neutrons. The method is rapid (3 minutes), sensitive (sub-nanogram detection limit), and nondestructive. A DNAA system has been installed at the 20-MW D2O reactor at the NIST Center for Neutron Research near Washington, DC. This system is able to analyze hundreds of samples per day, each as large as 40 mL and of arbitrary composition. Fast-neutron interference is negligible. To prevent irradiation of unexpectedly large quantities of actinides, a screening gamma-ray measurement is included in the procedure, with a detection limit of ~10 micrograms of U-235 or Pu-239 in a 10-minute count. THE STATUS OF URANIUM-SERIES MASS SPECTROMETRY FOR GEOCHRONOLOGY Steven J. Goldstein, Michael T. Murrell, and Andrew J. Nunn. Advances in geochemistry and geochronology are often closely linked to development of new technologies for improved measurement of elemental and isotopic abundance. At the beginning of the past decade, thermal ionization mass spectrometric (TIMS) methods were just beginning to be applied for longlived uranium-series nuclide measurement, with considerable advances in measurement speed, precision, and sensitivity over decay-counting methods. This opened up a number of applications in uranium-series geochronology and geochemistry of young sediments, volcanic rocks, and aqueous systems. Over the past decade there have continued to be advances in thermal ionization techniques, and the advent of alternative mass spectrometric methods, particularly multi-collector inductively coupled plasma mass spectrometry (MC-ICPMS), has continued to improve the quality of uranium-series studies. MC-ICPMS instruments have only recently been applied for uranium-series analyses, and so there is much potential for further development of measurement techniques using their unique capabilities. Second-generation instruments are now equipped with multi- 348 116 collecting ion counting capabilities, and such capabilities are also available for TIMS instruments. In particular, application of low-level multicollection to uranium, thorium, radium, and protactinium analysis may greatly improve analytical sensitivity for these measurements, thereby extending analysis to materials with lower uranium and thorium concentrations such as mineral separates for internal mineral isochron dating applications. Low-level multi-collection may also significantly improve many aspects of direct uranium and thorium analysis of minerals using laserablation techniques. Multi-collection ion counting may extend the range of analytes to uranium-series isotopes with shorter half-lives, such as lead-210 and actinium-227. These advances have improved evaluation of concordia among uranium-series chronometers and therefore the accuracy of uraniumseries dates. Examples from recent geochronology studies at our laboratory on corals, ice, and volcanic rocks will be provided to illustrate these improved analytical capabilities. 349 A SIMPLE DUAL ENERGY LUMP CORRECTION MODEL FOR USE IN THE QUANTITATIVE GAMMA ASSAY OF PLUTONIUM Stephen Croft, Robert D McElroy, Jr and Ram Venkataramen Canberra Industries Inc. and Debbie Curtis Canberra Harwell Ltd.. The application of quantitative high resolution gamma-ray spectrometry for the non-destructive assay of plutonium bearing items, such as waste drums, is complicated by self attenuation if the plutonum is present as lumps. By definition lumps are small compared to the bulk matrix and so are not accounted for in the gross matrix correction yet can excert a significant influence on the assay result. Compared to a calibration using dilute standards, self attenuation results in an under-reporting of the mass of plutonium present. The availability of representative standards is unrealistic for diverse waste streams and so a means to detect and compensate for the presence of lumps is needed. An experimental approach that can in principle generate an item specific correction factor is to exploit the differential attenuation between a set of gamma lines of known relative emission intensity. In the case of routine measurements of drummed Pu wastes the choice of lines is often limited, the most appropriate often being those at 129 kev and 414 kev from 239Pu. This paper discusses the problems and potential of exploiting this pairing in a simple dual energy approach to the long standing and challenging problem of self attenuation. Critical limits in radioactivity measurement : from Currie's definition to the international standard ISO-11929 publication Dominique CALMET (CEA/DAM France), Margarita HERRANZ (Dtr. dpto. Ing. Nuclear y Mec. de Fluidos, Escuela Superior de Ingenieros alda Urquijo s/n - 48013 Bilbao - Spain), F. LEGARDA and R. IDOETA. Following the publication in 1968 by Currie on a definition of the detection limits to be used for radiometric measurements, several authors have proposed alternative solutions to calculate the detection, decision and 350 117 quantification limits. The main purpose of these different approaches was to facilitate their use in laboratories dealing with routine radioactivity measurement. Those different approaches have generated discrepancies when calculating those limit values that could lead to misinterpretation. They affect the terminology used as well as the associated statistical formulae. Recently, documents published at a national level, such as MARLAP, and at international level, such as the standard 11979 edited by the International Standardization Organization (ISO), have attempted to clarify this issue. They follow two different approaches, the first one based on conventional statistics, the second using a Bayesian statistical perspective. However, when dealing with practical applications applied to specific situations observed in radioactivity measurement laboratories, both mathematical formulations produce identical results as those contained in Currie‘s work. This paper analyzes the different approaches and shows that the results obtained when computing these limits are similar for the activity determinations using gamma, alpha and beta spectrometry as well as for gross alpha and beta counting measurements. 351 THE MULTIPLE ISOTOPE MATERIAL BASIS SET (MIMBS) METHOD FOR ISOTOPE IDENTIFICATION WITH LOW- AND MEDIUM-RESOLUTION GAMMA RAY DETECTORS Robert Estep, Los Alamos National Laboratory; Benjamin Sapp, Los Alamos National Laboratory. The multiple isotope material basis set (MIMBS) method for isotope identification expands on our previous research on single- and dual-isotope algorithms. MIMBS couples the material basis set (MBS) method with ordinary response function fitting to allow the simultaneous identification of all library isotopes that are present in an unknown sample, with accurate correction for attenuation loss and spectrum distortion caused by the container or other intervening materials. The result is given as the fractional activity of each isotope identified (in the selected activity units) and the probability that the answer is correct. A drawback of MIMBS is that the algorithm cannot be accelerated by using precomputed matrix inverses, as has been done with our single- and dual-isotope solvers. Therefore, it requires much more computational power than our previous solvers and is not suitable for use on older model handheld identifiers. MIMBS can be run on a personal desktop or laptop computer to analyze spectra downloaded from older handheld instruments. In a parallel effort, our group is currently developing handheld identifiers with enough processing power to run the MIMBS algorithm in the field (see our related paper at this conference). ELEMENTAL ANALYSIS OF HAIR USING PIXE-TOMOGRAPHY AND INAA D Beasley, I Gomez-Morilla, N. Spyrou. Department of Physics, Centre for Nuclear and Radiation Physics, School of Electronics & Physical Sciences, 352 118 University of Surrey, Guildford, GU2 7XH, UK. 3D quantitative elemental maps of a section of a strand of hair were produced using a combination of PIXE-Tomography and simultaneous On/Off Axis STIM-Tomography at the University of Surrey Ion Beam Centre. The distributions of S, K, Cl, Ca, Fe and Zn were determined using the PIXE-T reconstruction package DISRA. The results were compared with conventional PIXE analysis of tomographic data as determined using Dan32. The overall concentrations determined by PIXE were compared with elemental data held in the University of Surrey Hair Database. All the entries currently in the database were produced using INAA. The merits of PIXE and INAA and the implications of tomographic PIXE analysis are discussed. The conclusions drawn from the PIXETomography analysis can be used to argue for more stringent procedures for hair analysis at the University of Surrey. 353 PM 2.5 Exposure from Vechicular Emissions C. M. Butler*, N.M. Spyrou*, I. Matthews**, C. Au-Yeung***. Epidemiological evidence on health effects from exposure to diesel ultra fines (0.1-0.3μm) is currently inconclusive in the U.K. Concentrations of metallic elements from diesel combustion, surface abrasion of catalytic converters and tyres are normally much more elevated near motorways/roadsides. Collected air particulates (PM10 and PM2.5) in the Cardiff region were analysed using INAA, ICIS, to explore the particulate exposure levels to residents within close proximity to roadsides. Bioaccumulated levels of sulphur and other elements in hair from residents at close proximity to motorways (8.01E+03 - 2.54E+05) and those in remoter areas (4.91E+04 – 1.21E+05) were in both cases, above the expected content (range) in human hair. However, S and Cu levels (μg/g) in airborne PM10 (from remote areas) had shown values, one magnitude higher in contrast to the main road-sites (and four times higher (in magnitude) to diesel levels). The average total mass loading (μg/m3) of particulates were also much higher in the remoter areas (6.94E+04 μg/m3), than the road-side areas (5.82E+00 μg/m3 average). Research in correlating particle number measurements (PM2.5) with toxicity (from vehicle emission) will be essential in revising the present metric (air quality) standards and emission inventories; influencing future use of alternative combustion fuels such as REE (Rapeseed-oil Ethyl Ester), LGE (liquefied petroleum gas) and CNG (compressed natural gas). ULTRA LOW LEVEL MEASUREMENTS OF ACTINIDES BY QUADRUPOLE-BASED ICP-MS F. Pointurier, A. Hubert, Ph. Hemet, Commissariat à l'Energie Atomique, DAM/DIF/DASE/SRCE. The purpose of the present work is to study the properties and application of a new commercial of-the-shelf quadrupolebased ICP-MS Thermo "X7" manufactured by VG Elemental (Winsford, Cheshire, UK) for precisely determining the concentrations and isotope ratios of U and Pu isotopes at the ultra-trace level. This instrument is 354 119 equipped with the S-option, which allows increasing the sensitivity. Comparing measurements (sensitivity, background, accuracy, precision, detection limit, abundance sensitivity, etc) were carried out with a single collector TIMS (VG 54-38), a double-focusing sector field ICP-MS (VG "Axiom SC") and with an older quadrupole-based ICP-MS (VG "PlasmaQuad2+"). The influences of mass bias and dead time corrections on isotopic ratios measurements were also investigated. We demonstrated that the Thermo "X7" ICP-MS exhibits excellent performance and is thus very suitable for the ultra-trace and isotopic analyses of long-lived actinide isotopes in environmental samples. Very low instrumental detection limits for 239Pu and 240Pu below the fg.ml-1 range are achievable. The accuracy and precision in the determination of the isotopic ratio remain worse than with TIMS, but is better than with older quadrupole-based or sector-field ICP-MS. 355 The IUPAC Project on: Terminology, Quantities, and Units Concerning Production and Applications of Radionuclides in Radiopharmaceutical and Radioanalytical Chemistry M.L. Bonardi, Università degli Studi di Milano and INFN-Milano, via F.lli Cervi 201, I-20090 Segrate, Italy. The current editions of the IUPAC Orange and Gold Books do not adequately cover the definition of terms used in nuclear and radiochemistry, and related nuclear sciences and technologies. A detailed analysis of relevant textbooks, journals, and IUPAC recommendations, published in the last decades, has been carried out by a Task Group of IUPAC Analytical Chemistry Division. It was found that several terms and definitions should be clarified or modified and then disseminated through the scientific and industrial communities. The new project will update and improve the terminology, quantities and units concerning production and application of radionuclides in radiopharmaceutical and radioanalytical chemistry. The task group will pay particular attention to the critical discussion of several concepts (e.g., carrier, specific activity, activity concentration, isotope exchange, speciation of carrier form) related to production of radionuclides and labelled chemical entities (i.e., radiopharmaceutical compounds). High specific activity radionuclides and labelled compounds are of increasing relevance and demand in the field of radiodiagnostics by gamma-scintigraphy, singlephoton emission tomography (SPECT) and positron emission tomography (PET, i.e., more properly the detection of annihilation radiation of positron emitters). While the molecular imaging techniques, based on emission of gamma photons of nuclear origin, do provide information on in-vivo biochemistry, pharmacokinetics, and metabolism of drugs and labelled chemical entities. ASSAY OF ELECTROFORMED ULTRA HIGH PURITY COPPER USING ISOTOPIC TRACERS DURING SAMPLE ELECTRODEPOSITION PRIOR TO INDUCTIVELY COUPLED 356 120 PLASMA MASS SPECTROMETRY (ICP/MS) ANALYSIS Eric Hoppe, Craig Aalseth, Orville Thomas Farmer III, Harry Miley , and Ron Brodzinski, Pacific Northwest National Laboratories (PNNL).. Current demands for ever increasing copper purity has exceeded our ability to measure the impurities present using existing analytical methodologies. Direct assay employing radiometric means require impractical amounts of material and exceedingly long sampling times. Other analytical tools such as Secondary Ion Mass Spectrometry (SIMS) or Inductively Coupled Plasma Mass Spectrometry (ICP/MS) lack adequate detection limits or dynamic range to perform direct assays. This presentation evaluates the use of electrochemical sample preparation in that it offers the advantage of removing the bulk copper while selectively concentrating the contaminant species. Isotopic tracers of the target contaminants are added prior to the electrodeposition. This approach offers the distinct advantage over conventional ion exchange sample processing in that it employs a single sample preparation for a broader spectrum of target analytes in the final residue prior to ICP/MS analysis. 357 EXPERIENCE GAINED FROM OPERATING AND MAINTAINING A GLOBAL NETWORK OF RASA STATIONS Joel C. Rynes, Bouvard Hosticka, Michael J. Pickering, George R. Shipman, and Erik Swanberg. Since the first Radionuclide Aerosol Sampler / Analyzer (RASA) station was certified as part of the International Monitoring System in November 2002, thirteen more have been certified. In addition, there are currently eight systems in various stages of manufacture, installation, and testing. General Dynamics has been involved with the installation or certification of all these systems as well as being directly responsible for the operation and maintenance of the eleven US stations and the British station on Diego Garcia. This presentation discusses the performance of the four US stations plus Diego Garcia for which there is more than one year each of operating experience. Longitudinal data is presented for stations with multi-year operating history. In addition, solutions to challenges unique to operating and maintaining stations installed in harsh and remote environments such as the arctic, Antarctic and isolated atolls will be discussed. DETERMINING THE VALUE OF RADIOLOGICAL AND NUCLEAR COUNTERMEASURES FOR HOMELAND SECURITY Randy Hansen, Tom Sanquist, Daniel Stephens, and Mark Tardiff, Pacific Northwest National Laboratory. The United States has committed itself and its resources to secure the homeland against radiological and nuclear attacks from terrorist foes. Nuclear spectrometry and instrumentation has become a cornerstone in this effort. As the United States invests in the research, development, and deployment of radiological and nuclear countermeasures, it is critical to accurately calculate their value. The value of a technology depends on two coupled components-the effectiveness of the instrument and 358 121 the total costs of utilizing the instrument. The total cost includes initial costs to procure and deploy, the costs to operate and maintain, and the economic impacts to those being screened. Assessing the overall value of a countermeasure is difficult because there is an inherent link between effectiveness of the instrumentation and the total costs. Furthermore, countermeasures are directed at preventing extremely rare events. This paper will outline the process for calculating the value of a countermeasure as a function of effectiveness, cost, and their dependence. 359 MORPHO - EMBEDDED MCA AND HV FOR SCINTILLATOR DETECTORS Michael Momayezi. Scintillator detectors use a crystal, a photo-multiplier (PMT), a high voltage power supply (HVPS) and a multichannel analyzer (MCA) for nuclear spectroscopy. Traditionally, the electronics is separated from the detector and the components are independent of each other. We have developed an integrated solution that mounts on the back of the photomultiplier and includes an embedded HVPS and a fully digital MCA. The MCA supports pulse capture and list mode data and can co-operate with others to synchronize time stamps and even perform coincidence measurements. Scintillator detectors exhibit substantial gain drifts over time and in response to temperature changes, which makes it a challenge to operate detector arrays. In the Morpho system the MCA controls the HVPS and employs a gain stabilization scheme that does not require embedded radioactive sources or light pulsers. A low-power version of the Morpho system may use as little as 0.3W and be powered through its USB-2.0 interface. A faster version requires 0.5W and will operate very well at count rates exceeding a million counts per second, given a fast enough scintillator. CHEMICAL ANALYSIS OF BRAZILIAN COMMERCIAL MILKS BY INSTRUMENTAL NEUTRON ACTIVATION ANALYSIS Luís Gustavo Cofani dos Santos, Elisabete A. De Nadai Fernandes, Fábio Sileno Tagliaferro and Márcio Arruda Bacchi - Laboratório de Radioisótopos - Centro de Energia Nuclear na Agricultura - Universidade de São Paulo. Milk is one of the most complete foods that are known, containing micronutrients, carbohydrates, aminoacids and lipids in appropriate proportions to the human nutrition. The Food and Agriculture Organization (FAO) describes the milk sector as strategic for the reduction of the hunger in the world. However, the composition of milk is not absolute, many factors may affect the quality of the final product. The objective of this work was the determination of toxic and essential elements in Brazilian commercial milks by instrumental neutron activation analysis (INAA). The potential of the INAA in the chemical analysis for the milk matrix was also evaluated. This study is part of a large project (FAPESP 04/15966-9) on the characterization and identification of Brazilian milks. Bovine fluid milk was acquired in the local market of Piracicaba, São Paulo, Brazil. The milk samples were freeze-dried and analyzed by k0-INAA. Certified reference 360 122 materials from National Institute of Standard and Technology (NIST) and International Atomic Energy Agency (IAEA) were used to assure the quality of the results obtained. The elements Br, Ca, Co, Cs, Fe, K, Na, Rb and Zn were quantified. The conditions employed for the INAA and the results will be discussed. 361 Innovations in Radiochemistry Education at Washington State University J. T. Elliston, Nuclear Radiation Center, Washington State University and S. B. Clark, Department of Chemistry, Washington State University. WSU will work together with Pacific Northwest National Laboratory (PNNL) to offer innovative programs of education and outreach. One aspect will be a Summer Education and Research Opportunity for faculty members from regional colleges and universities that do not have nuclear programs, but that do offer some form of research opportunities for undergraduate and/or graduate students. This summer opportunity will fund a summer stipend, all travel expenses, room, board, and course materials for up to five faculty members to come to WSU to learn about nuclear techniques and applications. Through their one-month summer experience, they will learn how to apply neutrons in their research and can complete analyses during that time. They will also receive educational materials to integrate into the courses they teach. They will be encouraged to continue to use the WSU reactor facilities after their one-month experience ends. In addition, a one week radiochemistry summer experience will be presented for up to five high school science teachers who will come to WSU to learn how to integrate various aspects of nuclear science into their high school science curricula. They will be provided with course materials and ideas to use in their classrooms. They will also arrange field trips to WNSA university research reactors (URR) so their students can use the facilities and learn about career opportunities. Travel, room, board, and course materials will be provided. To accomplish these summer activities, the radiochemist will be responsible for establishing the summer programs from initial planning to execution, for recruiting participants, arranging their appointments, and conducting the actual summer programs with assistance from WSU faculty and national laboratory staff. These activities will be integrated into the summer school program for undergraduate students that PNNL is planning to offer as part of its Advanced Nuclear Science and Technology Initiative. As appropriate, this program will be expanded to other western national laboratories. 362 MATRIX ASSISTED LASER DESORPTION TIME OF FLIGHT (MALDI TOF) MASS SPECTROMETRY – EXCELENT TOOL IN ANALYTICS J. Havel*ab, aDepartment of Analytical Chemistry, bLaboratory of Plasma Physics and Plasma Sources, Faculty of Science, Masaryk University, 123 Kotlarska 2, 611 37 Brno, CZECH REPUBLIC. MALDI TOF MS is one of the most important analytical tools e.g. in proteomics as it is able to ionize biomolecules without their massive destruction. It is the leading-edge tool for studying peptides, proteins, biotechnological and pharmaceuticals products, polymers, etc. up to masses even over 1 M Daltons. High resolution can be reached and structural analysis is also possible applying Post Source Decay (PSD). However, MALDI can also be used with advantage for environmental and radioanalytical analysis. In this paper principals of MALDI TOF MS will be elucidated and on selected examples from analysis of waters, soil, HT materials, food/feed, etc., its unique possibilities will be demonstrated. Laser Desorption Ionization (LDI) or Laser Ablation (LA) of insoluble materials like ceramics, metals, soils etc. enables without any pre-treatment to reach highest sensitivity and selectivity. MALDI TOF MS offers great advantages for simultaneous analysis of inorganic and organic compounds including isotopes in various matrices with minimal sample amount. Future trends and development are to be discussed. This work was supported by Grant Agency of the Czech Republic, Grant No. 203/04/2105 and Ministry of Education, Youth and Sports of the Czech Republic, project no. MSM 00 216 224 11. 363 Monte Carlo study of photoneutron production in the Varian Clinac 2100C linac Andy Ma, University of Surrey, UK; Joseph Awotwi-Pratt, Norfolk and Norwich University Hospital, UK and Nicholas M. Spyrou, University of Surrey, UK. Medical linear accelerators (linacs) are used extensively in modern radiotherapy for their flexibility and versatility. As the treatment regime moves from low-energy, e.g. 6 MV, photon beams to high-energy beams, 10 to 25 MV, neutrons are produced in the treatment head via photonuclear disintegration reactions of the photon with the materials of the components of the linac head. Recent works suggest the possibility of utilising the photoneutrons from the linac as an alternative to nuclear reactors in boron neutron capture therapy (BNCT). Understanding the photoneutron production in the treatment head becomes important. It is also important for radiation protection to the staff and general public, as well as for estimating the concommittant dose to the patient. This work used the general-purpose Monte Carlo code MCNPX to model the Varian Clinac 2100C linac with 18MV photon beams. Simulations are carried out for several field sizes from fully closed multileaf collimator and jaws to maximum opening. Photoneutron productions in various head components are estimated from the photon fluence and the photoneutron production cross sections. The results will be (are) presented and they serve as a basis for further studies on using linac as an alternative neutron source in BNCT and radiation protection issues arising from photoneutrons in the treatment room. RADIOANALYTICA L TECHNIQUES APPLIED TO FOOD SAMPLES TO MONITOR THE NUTRITIONAL STATUS OF 364 124 CHILDREN FROM TANZANIA Mohammed, NK., Spyrou, NM. Department of Physics, University of Surrey, Guildford, Surrey. GU2 7XH. UK.. Information on the nutritional status of individuals and populations is essential in order to initiate the solution for malnutrition. The information can verify the nature of the nutrition problem and the effectiveness of the specific solution or intervention. Hence, studies of essential elements in food and diets are fundamental to the improvement of human welfare and resistance to disease. Particularly in developing countries the intake of essential as well as toxic elements is entirely through diet. The toxic elements in the food might be associated with the environmental pollution from uncontrolled industries and domestic wastes and/or from the deposition of vehicle emissions. So far little information exists for developing countries that could provide a scientific basis for food programmes suited to the local needs and conditions. Therefore, in this work two staple foods consumed by children from a number of regions in Tanzania (rice and maize flour) have been analysed to determine essential and toxic element levels. The samples were analysed at the Imperial College Reactor Centre using INAA with short irradiation and at the University of Surrey Ion Beam Centre using PIXE analysis. The results will be a basis for further collection and detection of samples, which include the hair to monitor nutritional status of children in Tanzania. Because of the use of phosphate fertilizers low-level γ-ray spectrometry was also employed to measure radioactivity accumulations. 365 PROSPECTS OF HIGH ENERGY MEDICAL LINEAR ACCELRATORS IN BNCT, A MONTE CARLO SIMULATION USING VOXELISED PHANTOM A.Alfuraih,A.MA,A.A.Alghamdi and N.M Spyrou. Department of Physcis, University of Surrey, UK. Boron Neutron Capture Therapy (BNCT) is based on the nuclear reaction (n, α) that occurs when 10B is irradiated by thermal neutrons yielding high linear energy transfer α particles and recoiling 7Li nuclei. High energy photon beams from Medical Linear Accelerators (linacs) which are used in radiotherapy produce undesirable neutrons, beside the clinically useful electron and photon beams. Neutrons are produced from the photonuclear reactions (γ, n) of high energy photons with high Z-materials which compose the accelerator head.In this paper the possible use of these undesirable neutrons for BNCT is investigated, making use of high energy linacs already installed in hospitals, primarily for high energy electron and photon (bremsstrahlung) therapy and applying them in the context of BNCT. The photoneutron components emitted by the accelerator is the source for Monte Carlo simulations of the interactions that take place within voxelbased phantom of the head .The neutron flux across the head phantom, using different moderator arrangements and different techniques in order to increase the thermal neutron flux at the targeted site is determined. To make use of linacs for BNCT will be advantageous in the sense that the setting in a hospital department is much more acceptable by the public than a reactor 125 installation. This will mean less complications regarding patient positioning and movement with respect to the beams, additional patient transportation and management will be more cost effective. 368 POLYMER THIN FILMS FOR THE RAPID SEPARATION AND MEASUREMENT OF RADIONUCLIDES R. Shane Addleman, Matthew O‘Hara, Chris Brown, Jay Grate, Oleg B. Egorov. We have found that semipermiable polymer thin films loaded with lipophilic extractants can act as selective sorbent layers that are effective at capturing radionuclides. Several membrane chemistries that are selective for actinides have been explored and the governing factors have been identified. The extractant loaded thin films selectively concentrate actinide ions of interest into a thin layer on the surface, thus enabling direct and rapid assay of extracted isotopes with the energy resolution comparable to that of conventional alpha spectroscopy. SPECIATION ANALYSIS OF IODINE IN BOVINE MILK BY CHEMICAL SEPARATION AND NEUTRON ACTIVATION Keila Isaac-Olive, A. Chatt, SLOWPOKE-2 Facility, Trace Analysis Research Centre, Department of Chemistry, Dalhousie University, Halifax, Nova Scotia, B3H 4J3, Canada. Iodine is an essential trace element for human beings. Either the lack or the excess of iodine can cause health problems. The World Health Organization (WHO) has estimated that about 740 million people around the world suffer from iodine deficiency disorders (IDD). Cases of IDD are not that uncommon in many countries of Africa and Asia while in North American and European countries the average daily dietary intake of iodine can be up to 6 times the recommended value. The main source of iodine for general population groups is food items such as fish, egg and milk. Milk provides 16-30% of the dietary iodine intake, and in many countries in the Northern hemisphere high milk consumption could be the major contributor to bodily iodine intake. The bioavailability and toxicity of an element depends strongly on its chemical species, and iodine is no exception. However, not much work has been published on speciation of iodine in milk, perhaps due to the lack of sensitive methods. We first developed a pseudo-cyclic epithermal instrumental neutron activation analysis method in conjunction with Compton suppression spectrometry (PC-EINAA-CSS) for the determination of sub-ppb levels of iodine, and then designed a speciation scheme for iodine in milk. We used ion exchange chromatography to isolate inorganic iodine species from the organic ones followed by the separation and identification of various inorganic species; employed solvent extraction to isolate lipid-containing iodine species followed by further fractionation using a silica gel column; and applied ammonium sulfate precipitation to separate protein-bound iodine species followed by the separation of proteins to casein and whey. Details of the method will be presented along with results. 369 126 370 ACTIVATION ANALYSIS FOR Dy, Hf, Rb, Sc AND Se IN SOME GHANAIAN CEREALS AND VEGETABLES USING SHORT-LIVED NUCLIDES AND COMPTON SUPPRESSION SPECTROMETRY B.J.B. Nyarko1,2,3, E.H.K. Akaho2, J.J. Fletcher3, A. Chatt1, 1SLOWPOKE-2 Facility, Trace Analysis Research Centre, Department of Chemistry, Dalhousie University, Halifax, Nova Scotia, B3H 4J3, Canada. 2Ghana Atomic Energy Commission, P.O. Box LG 80, Legon-Accra, Ghana. 3Physics Department, University of Cape Coast, Cape Coast, Ghana. Instrumental neutron activation analysis (INAA) has been used to analyze various types of cereals and vegetables from Ghana using relatively shortlived nuclides (t1/2<65 s) and Compton suppression spectrometry. The samples were irradiated for 10 s in the inner pneumatic irradiation site (#2) at a neutron flux of 2.5x10e11 cm-2.s-1 at the Dalhousie University SLOWPOKE-2 reactor (DUSR) facility. The samples were then manually transferred to a Compton suppression gamma-ray spectrometry system within 20 s and counted for 40 s to quantify Dy, Hf, Rb, Sc and Se through their short-lived nuclides, namely 165m-Dy (t1/2=75.4 s, 108.2 keV gamma-ray), 179-Hf (18.68 s, 214.5 keV), 86m-Rb (61.0 s, 555.4 keV), 46m-Sc (18.7 s, 142.5 keV) and 77m-Se (17.4 s, 161.9 keV). The overall uncertainties associated with the analytical method have been evaluated. The details of the methods developed, results obtained, and accuracy of measurement will be presented. SIMULTANEOUS DETERMINATION OF Cd, Cr, Hg IN SEAWEED SAMPLES BY CLOUD POINT EXTRACTION AND NEUTRON ACTIVATION ANALYSIS Y. Serfor-Armah1,2,3, D. Carboo3, R. K. Akuamoah3, A. Chatt1. 1Trace Analysis Research Centre, Department of Chemistry, Dalhousie University, Halifax, Nova Scotia, B3H 4J3, Canada, 2Department of Chemistry, Ghana Atomic Energy Commission, P. O. Box LG 80, Legon-Accra, Ghana, 3Department of Chemistry, University of Ghana, P. O. Box 56, LegonAccra, Ghana. A simple one-step cloud point extraction preconcentrationneutron activation analysis (NAA) method has been developed for the simultaneous determination of Cd, Cr, and Hg. The method is based on separation of non-ionic surfactant polyoxyethylene nonylether (PONPE-20) in aqueous solution after the formation of a complex with a mixture of two chelating agents, namely, 1-(2-pyridylazo)-2-naphthol (PAN) and 1-(2thiazolylazo)-2-naphthol (TAN). The samples were irradiated for 3 h in the inner sites of the Dalhousie University SLOWPOKE-2 reactor (DUSR) facility at a thermal neutron flux of 2.5 x 1011 cm-2 s-1. The chemical variables affecting the separation phase were optimized. The recoveries of these elements under the optimum conditions (i.e. pH=8.5, [PAN/TAN]=1 x 10-4 M, [PONPE-20]=0.1% (wt), ionic strength=0.05 M KNO3, T=40oC) and preconcentration of 20-30 mL of sample solution were above 98%. The detection limits of Cd, Cr, and Hg were 6.0, 3.6 and 1.2 ppb, respectively. Relative standard deviations were less than ±4%. The details of method 371 127 developed, results obtained, precision and accuracy of the measurements will be presented. The method was successfully applied to the simultaneous determination of Cd, Cr, and Hg in various Ghanaian seaweed samples. 372 ANALYSIS OF ACTINIDES IN ENVIRONMENTAL MATRICES BY ICP-MS – A PROCEDURE BASED ON CHEMICAL SPECIATION Christina Greis and Bert Allard, Man-Technology-Environment Research Centre, Örebro University, SE-701 82 Örebro, Sweden. The chemical speciation of the actinides in environmental waters is largely defined by the redox conditions leading to different oxidation states (An(III), An(IV), An(V), An(VI)), hydrolysis related to pH (An(IV)>An(VI)>An(III)>An(V)) and complexation with carbonate (An(VI)>An(III)>An(V)>>An(IV)). A strategy for the separation of actinides (Th, U, Np, Pu and Am) based on their differences in redox states and complexing properties is outlined in this paper.Most schemes for separation of actinides from an aquatic solution are based on recovery of an individual element by e.g. ion exchange, liquidliquid extraction or solid phase extraction, when the differences in properties between the various oxidation states (charge, ligand affinity, adsorption properties etc) are utilized. A drawback with many procedures is the sometimes poor selectivity and the addition of interfering agents that have to be removed prior to analysis. For environmental waters some major steps are isolation/removal of U as a hexavalent anionic carbonate complex, and isolation/removal of Pu (and Np) as a tetravalent complex. The following approach has been tested: Non-complexing agents, O2, H2O2 and H2, to adjust Eh, Non-interfering agents, NaOH and HNO3, to adjust pH. Complexing agents, CO2/CO32- (and OH-). Selective adsorbents, complexing agents on a solid carrier. PLUTONIUM REMOBILISATION IN A HUMIC RICH LAKE Christina Greisa, Anders Dükera, Bert Allarda, Per Roosbc, Elis Holmb. aMan-Technology-Environment Research Centre, Örebro University, SE701 82 Örebro, Sweden. bDepartment of Radiation Physics, Lund University Hospital, SE-221 85 Lund, Sweden. cRisoe National Laboratory, DK-4000 Roskilde, Denmark.. Plutonium levels as high as 4x10were previously observed in Lake Svartsjön, Sweden. This is far above expected levels in natural fresh water systems contaminated by nuclear test fallout, which indicates that plutonium must be released from bottom sediments and solubilized in this lake. Some 200 l of water from the lake was collected and three fractions were prepared: (1) The fraction adsorbed on DEAE; (2) The fraction coprecipitated/flocculated with CaCl2 after removal of the DEAE-fraction, and (3) The fraction coprecipitated with FeCl3 after removal of both the DEAE- and Ca-fractions. The observed distribution of plutonium (analysis by ICP-MS) between the three fractions is discussed, as well as possible processes behind the distribution (including release from stationary bottom sediments into the water body). Pronounced accumulation in fractions (1) and (2) indicates that plutonium is predominantly associated 373 128 with high-molecular weight humic matter which is responsible for a release from bottom sediments and from adjacent bog areas. The distribution of plutonium (organic and inorganic species, in stationary solid phases as well as suspended colloidal phases) is further discussed, and conditions when a mobilization of fall-out plutonium due to formation of organic (humic) species can occur are defined. 374 Energy Information Usage in Plastic Scintillator Material James Ely, Richard Kouzes, and Denny Weier. Plastic scintillator material is often used for gamma-ray detection in many applications due to the relatively good sensitivity and cost-effectiveness compared to other detection materials. However, due to the dominant Compton scattering interaction mechanism, full energy peaks are not observed in plastic scintillator spectra and isotopic identification is impossible. Typically plastic scintillator detectors are solely gross count detectors. In some safeguards and security applications, such as radiation portal monitors for vehicle screening, naturally-occurring radioactive material (NORM) often triggers radiation alarms and results in innocent or nuisance alarms. The limited energy information from plastic scintillator material can be used to discriminate the NORM from targeted materials and reduce the nuisance alarm rate. An overview of the utilization of the energy information from plastic scintilllator material will be presented, with emphasis on the detection capabilities and potential limitations for safeguards and security applications. TESTING AND PROVISIONAL OPERATION OF THE IMS RADIONUCLIDE MONITORING NETWORK: THE CHALLENGE Franca Padoani, Luis Cella, Erin Mcwilliams, Xiankai Shen, Robert Werzi. Comprehensive Nuclear-Test-Ban Treaty Organization. A world-wide radionuclide network of 80 stations, 40 of which with noble-gas-detection capability, and part of the International Monitoring System (IMS) has been designed to monitor compliance to the Comprehensive Nuclear-Test-Ban Treaty (CTBT). While in the preparatory phase, pending entry into force of the Treaty, the certified stations are provisionally operated and so far an experience of over 100 station year has been accumulated for particulate stations. Noble gas stations are still under testing, though the operational experience is fast growing and is now more or less equivalent to ten station year. An operation and maintenance strategy is being developed on the basis of the collected experience and the analysis of equipment failures and critical problems. PROTEIN- AND POLYSACCHARIDE-BOUND TRACE ELEMENTS IN EDIBLE JAPANESE SEAWEEDS BY NEUTRON ACTIVATION M. Fukushima1, K. Isaac-Olive2, Y. Nakano3, A. Chatt2. 1Ishinomaki Senshu University, Ishinomaki, Miyagi, 986-8580, Japan; 2SLOWPOKE-2 Facility, Dalhousie University, Halifax, Nova Scotia, B3H 4J3, Canada; 3Research Reactor Institute, Kyoto University, Sennann, Osaka, 590-0494, 375 376 129 Japan. Edible seaweeds play an important role as a daily source of minerals for Japanese population groups. It is therefore of interest to estimate the average daily dietary intakes of minerals from seaweeds. In this study, bioavailable (BA) fraction of trace elements in edible seaweeds were estimated by in vitro enzymolysis. The BA levels were calculated from the total, water soluble dietary fiber (WSDF), and non-soluble dietary fiber (NSDF) element levels. Then, proteins and water soluble polysaccharides (WSPS) were extracted using a mixture of Tris buffer (pH 9.0) and 0.1% SDS, and centrifuged after saturating it with ammonium sulfate. Crude WSPS was precipitated by adding ethyl alcohol. All fractions were analyzed to determine Br, Ca, Co, Cr, Fe, I, Mg, Mn, Rb, Sb, Sc, and Zn by neutron activation using the Dalhousie University SLOWPOKE-2 reactor (DUSR) facility in Canada, and the Kyoto University reactor in Japan. Details of the method and the result will be presented. 377 FURTHER DEVELOPMENT OF A GRADUATE LEVEL COURSE IN NUCLEAR AND RADIOCHEMISTRY Alex Plionis and Sheldon Landsberger, University of Texas. Since several years we have implemented a web-based graduate level course in nuclear and radiochemistry. While the first modules were primarily focused on basic nuclear and radiochemistry concepts, we have now developed lectures based on radiochemistry processes. These include actinide chemistry, chemical reactions and stoichiometry, solubility, phase portioning and adsorption. A detailed account of the lectures and laboratories associated with them will be presented. Assessment of radioactivity of environmental and nuclear reactor decommissioning samples by gamma-ray spectrometry using Monte Carlo simulation combined with experimental calibration 1Horia Hulubei National Institute for Physics and Nuclear Engineering (NIPNE), PO Box MG-6, 077125 Bucharest, Romania;2University of Bucharest, Faculty of Physics, Atomic and Nuclear Physics Department, PO Box MG-11, 077125 Bucharest, Romania. The radioactivity of various types of samples from the environment (soil, sediment, water, vegetation) and waste samples provided by the decommissioning activity of the VVR-S reactor at NIPNE was measured using a high resolution, low background spectrometer based on a HPGe EG&G Ortec detector (GEM 30185 type). The detector efficiency calibration was performed using the GESPECOR software [1]. This program, based on Monte Carlo simulation, provided also the correction factors for gamma-ray coincidence summing and attenuation effects in volume samples of different geometries (e.g. Sarpagan and Marinelli types). Artificial and natural radionuclides in the samples, such as 137Cs, 60Co, 241Am, 152Eu, as well as 40K and 238U, 235U and 232Th series decay products were investigated. The activity results obtained were compared with those determined by a relative method using certified solid volume sources prepared by the Radionuclide Metrology Laboratory (RML) 378 130 of NIPNE. For the analytical quality assessment appropriate IAEA reference materials of natural origin (e.g. IAEA-375 soil, IAEA-135 sediment, IAEA373 grass, IAEA-156 clover) were employed. 379 Separation of plutonium from soil samples and determination of 240Pu/239Pu ratios by HR-ICP-MS Yasuyuki MURAMATSU (Gakushuin University), Satoshi YOSHIDA (NIRS) and Sinnosuke YAMAZAKI (Tokyo Nuclear Service). In order to understand the levels and distribution of Pu in the environment we have studied analytical procedures of this element by High resolution-type ICPMS. Special attention was paid to the extraction procedure of Pu from soil using different acids. We found a variation of 240Pu/239Pu ratios due to the difference of acid concentrations used for the extractions. A microwave oven was also applied for the sample digestion with a mixture of nitric, fluoric and perchloric acids in a Teflon-bomb. After the separation of Pu by ionexchange resin, it was determined by HR-ICP-MS with a micro-flow nebulizer. For the analysis of surface soil samples, we could reduce the sample size down to about 1 g or less. Concentrations of Pu and 240Pu/239Pu ratios were determined in soil samples collected from different locations in Japan, including Nishiyama area of Nagasaki-city. The 240Pu/239Pu ratios were in most cases 0.16 to 0.19, excluding samples from Nishiyama area (around 0.03). Vertical variation of the isotope ratios in soil was also studied and found that the ratios were changed according to the soil depth. This might be explained by the different behavior of Pu species in the soil environment. Determination of I-129 by AMS for environmental samples collected in Japan Yukari TAKADA, Yasuyuki MURAMATSU (Gakushuin University), Hiroyuki MATSUZAKI and Kazuhiro KATO (The University of Tokyo). Iodine-129 is one of the most important radionuclides in environmental sciences and geochemistry. In this study, we have developed an appropriate procedure for the separation of iodine from environmental samples such as soil and 129I /127I ratio was determined by AMS (accelerator mass spectrometry). The sample was heated in a quartz tube and the evaporated iodine was collected in a trap solution containing TMAH (tetramethyl ammonium hydroxide). After iodide carrier was added, it was purified by solvent extraction. Iodine was finally precipitated as AgI, which was determined by AMS using gas counter system at MALT (Micro Analysis Laboratory, Tandem accelerator), The University of Tokyo. A sufficient resolution was obtained to isolate 129I ion from molecular fragment. In case of soil samples, we used less than one gram of sample to detect background level of 129I, i.e. 129I /127I ratio of <1x10E-10. Concentrations of stable iodine were analyzed by ICP-MS. Using this method we have analyzed some reference materials to examine analytical feasibility. Several soil samples collected from different places in Japan (including the vicinity of nuclear 380 131 spent fuel reprocessing plant) were determined for I-129. 381 RAPID NAA DETERMINATION OF THE ISOTOPIC ENRICHMENT OF 18O IN WATER MIXTURES USED FOR CYCLOTRON 18F PRODUCTION. Duke1, M.J.M., Ambeault1, R.J. and Wilson2, J. 1 - SLOWPOKE Nuclear Reactor Facility, University of Alberta; 2 - Cross Cancer Institute Edmonton, Alberta, CANADA.. Over the past 10 to 15 years the field of nuclear medicine has seen significant growth in the use of positron emission tomography (PET) for imaging purposes. In large part this growth has been fuelled by the synthesis of 18F-labelled radiopharmaceuticals, particularly 18F-labelled fluorodeoxyglucose (18FDG), for use in oncology, cardiology and neurology. Cyclotron production of 18F-fluoride results from the proton bombardment of stable 18O, most commonly in the form of an isotopically enriched water (H218O) target. Measurement of the enrichment of 18O in prospective cyclotron target water is highly desirable when calculating the expected yield of 18F. This is particularly the case when the target water becomes diluted with H216O through repeated harvesting of 18F. Historically, INAA has been used to determine the 18O contents of 18Oenriched waters used in energy expenditure studies via the thermal neutron report the use of cyclic and pseudo-cyclic NAA with a SLOWPOKE nuclear reactor for the rapid determination of the 18O-enrichemnt of cyclotron target waters used for 18F production. SELECTED TRACE AND MINOR ELEMENTS IN SEDIMENTS FROM WATER BODIES AT THE WESTERN REGION OF PARAGUAY. J.F.Facetti-Masulli1. P. Kump2.- 1Hydroconsult SRL, de Gaulle 980Asunción-Paraguay. 2Josef Stefan Institute, 1000 Ljubljana, Jamova 39, Slovenia.. Bottom sediments from water bodies (creeks and small rivers) sited at the Western Region of Paraguay (Chaco) were investigated with XRF techniques. Selected trace elements analyzed in sediments were Zr, Nb, Ba, La, Ce, Nd using an Am -241 source, whereas Ti, Mn, Fe which are very often correlated with the above elements, using a Mo tube. The analysis of complex spectra was performed by the AXIL software, and the quantitative analysis, by the QAES software. Rare Earth Elements are considered as useful indicators of geochemical processes, and in this case, of provenance. Usually they maintain their primary relation and are transferred almost directly into sediments. The water bodies were: río Aguaray guazú, río Negro, río Montelindo and río Verde. Their values herefound, absolute and normalized, are well correlated with sediments of a wetland to them related. EVALUATION OF SEMICONDUCTOR DETECTORS TO IMAGE THREE PHOTON ANNIHILATION FOR POSITRON EMISSION TOMOGRAPHY 382 383 132 Elfatih Abuelhia ( Department of Physics, University of Surrey, Guildford, Surrey, GU2 7XH, UK), K. kacperski ( Institute of Nuclear Medicine, University College London, Middlesex Hospital, London W1T 3AA, UK), S. kafala ( Department of Physics, University of Surrey, Guildford, Surrey, GU2 7XH, UK ) N.M Spyrou (Department of Physics, University of Surrey, Guildford, Surrey, GU2 7XH, UK). Positron emission tomography (PET) is rapidly becoming the main nuclear imaging modality of the present century. In PET, radioisotopes of major elements found in the human body (11C, 13N, 15O, 18F) label metabolically active compounds and are used for imaging a large number of physiological and metabolic processes. The future of PET instrumentation relies on semiconductor detectors. Progress in research and development of semiconductor materials over the last few decades has created considerable interest particularly in medical imaging. The requirements are for broad gap, high density detector materials that can operate at room temperature with good energy resolution (<2% at 511 keV), high stopping power and efficiency. Moreover, they do not require bulky and cumbersome photomultiplier tubes, in contrast to scintillators. Three-photon positron annihilation has been recently investigated as a novel imaging modality, which demands these crucial semiconductor detector characteristics. In this work the evaluation of semiconductor detectors to construct a simple three-photon positron annihilation scanner has been explored with respect to detector and scanner size. The characteristics of energy resolution versus count rate and the point-spread function of the three-photon positron annihilation image profile from triple coincidence measurements are presented. An analytical model is applied to evaluate the experimental work 385 Atlantic Forest: a natural reservoir of chemical elements Elvis Joacir De França, Elisabete A. De Nadai Fernandes, Márcio Arruda Bacchi, Camila Elias. The accumulation of chemical elements in biological compartments is the strategy developed by tropical species to survive in growing unfavorable conditions (e.g. poor nutrient content soil). By means of advanced multielement techniques, chemical element concentrations in such compartments are easily assessed. When expressed in total quantity terms (kg/ha for example), the numbers become quite outstanding. However, there is no consensus about the maintenance of such concentrations in the biological compartments throughout time. Nowadays, the São Paulo State, Brazil, has only 6% of the original area of the Atlantic Forest, considered one of the hottest hotspots for the global biodiversity conservation. Despite the ecological and environmental importance, this study also focuses on the Atlantic Forest of the Parque Estadual Carlos Botelho (PECB) as an impressive reservoir of chemical elements. About 20 elements were determined by instrumental neutron activation analysis (INAA) in leaf, soil, litter and epiphyte compartments. The 20 most abundant species from the PECB long-term plot (about 20,000 trees belonging to 200 species) were sampled in different occasions (period of two years). Elements like Ba, Co, 133 Cs, Rb, K, Na, lanthanides, Sc, Sr and Zn showed high concentrations in leaves without apparent seasonality at the 95% confidence level. Considering the Atlantic Forest dynamics, the total quantities could be computed for the long-term plot based on the species occurrence. Moreover, quantities could be extrapolated for the remaining Atlantic Forest, showing the anthropogenic impact of deforestation on chemical elements cycling. 386 Centrifugal electrodissolution system for irradiated rhodium target material used for the cyclotron 103Pd production M. Sadeghi1,2, P. Van den Winkel3, H. Afarideh2 and M. Haji-Saeid2, L. De Vis3, R. Waegeneer3,A. De Schrijver3,1Faculty of Engineering, Research and Science Campus, Islamic Azad University, Tehran, Iran3. VUB-Cyclotron, Laarbeeklaan 103, B1090 Brussels, Belgium. A new centrifugal electrodissolution technology was developed. It allows timecontrolled electrodissolution of proton irradiated rhodium powder, fragments, cut wires and foils in a limited volume of hydrochloric acid. The mini-reactor setup includes a hollow, cylindrical electrographite workingelectrode (WE) receptacle fitted with an insulating PEEK bottom disk and with a PMMA cylindrical top-piece that increases the volume of the system. A cylindrical graphite counter electrode (CE) of appropriate diameter is mounted axially and extends up to 1mm of the bottom disk. The WE is mounted on the axis of a dc motor/tacho combination operating at 1000 rounds per minute. When filled with hydrochloric acid (40 ml, up to 12N) that contains the rhodium (up to 3 g) and when applying a high alternating current (up to 30 A) between working and counter electrode, centrifugal force and heat-generated fluid convection currents will result in the target material to be collected and to be rapidly dissolved at the lower section of the vertical wall of the WE where a current density up to 2 A.cm-2 is obtained and where the concentration of the electroactive chlorine species dissolving the target material is maximum. The system is fitted with three sensorfeedback systems that allow volume (40 ± 2 ml), temperature (85 ± 2 °C) and current (30 ± 0.5 A) to be kept between narrow limits. A RADIOANALYTICAL APPROACH TO DETERMINE 238PU, 239+240PU, 241PU AND 241AM IN SOILS COLLECTED FROM THE SUBSURFACE DISPOSAL AREA OF THE IDAHO NATIONAL LABORATORY R.F. Payne and S.B. Clark, Department of Chemistry, Washington State University. Until 1970, the Idaho National Laboratory (INL) operated a disposal facility for radioactive waste called the Subsurface Disposal Area (SDA). The SDA was used to bury containers of low-level transuranic waste received primarily from Rocky Flats Site in Colorado. One area in the SDA, called Pit 9, was used to dispose of 30 kg of transuranics as mixed waste (4100 m3 total volume of waste). Rocky Flats was a site for actinide separations to produce weapons components made of plutonium enriched in 239Pu. A flood in 1969 at Pit 9 caused the release of Am and Pu from the 387 134 waste drums resulting in contamination of INL soils, and redistribution of the soils within the SDA facility. Soils around the SDA were collected in the early 1970's, analyzed for 238Pu, 239+240Pu, and 241Am and then stored. We have reanalyzed some of those soils more than 25 years later using an alternative approach that is based on a combination of traditional and new radioanalytical techniques. In particular, we are interested in the ability to determine the activity of 241Am resulting from ingrowth from 241Pu decay. 241Am was determined prior to soil dissolution using the 59.5 keV gamma emission by HPGe gamma spectrometry. The soils were then completely dissolved using a lithium metaborate fusion method, which was followed by anion exchange to separate the Pu fraction from the matrix. The Pu fraction was used to prepare an electrodeposited sample from a sulfate matrix for determination of 238Pu and 239+240Pu by high resolution alpha spectrometry. Lastly, 241Pu was determined using liquid scintillation counting (LSC). The Pu was recovered from the electrodeposition planchets by boiling them in 8 M HNO3. After a short anion exchange column to remove traces of Fe and Ni, the Pu was dried down in the LSC vial, then brought back into solution with dilute HCl before mixing with a scintillation cocktail. The 241Pu activity was discriminated from any Pu activity using energy resolution. In this presentation, the methods used will be described, along with estimates of limits of detection and other statistical considerations. Results of 238Pu, 239+240Pu, 241Pu and 241Am activities from two different locations near Pit 9 and two different depths at those locations will be presented. This information will be used to demonstrate that the amount of activity of 241Am from the ingrowth from 241Pu is greater than would be expected solely from the production of nuclear components. This suggests that one source of 241Am may be from waste streams that resulted from reprocessing and purifying Pu pits. 388 INVESTIGATION OF CHARGED PARTICLE INDUCED ROUTES FOR PRODUCTION OF 103PD F. Tárkányi1, A. Hermanne2, S. Takács1, F. Ditrói1, J. Csikai1,3, Király B.1 M.. S. Uddin4, M. Hagiwara4, M. Baba4, T. Ido4, Yu. N. Shubin5, S. F. Kovalev5, 1Institute of Nuclear Research of the Hungarian Academy of Sciences, Debrecen. Hungary, 2Cyclotron Laboratory, Vrije Universiteit Brussel, Brussels, Belgium, 3Institute of Experimental Physics, Debrecen University, Debrecen, Hungary, 4Cyclotron and Radioisotope Center, Tohoku University, Sendai, Japan, 5Institute of Physics and Power Engineering, Obninsk, Russian Federation,. The use of the radionuclide 103Pd (decay essentially by EC) for permanent brachytherapy is rapidly increasing. This radioisotope can be produced in reactors via a 102Pd(n,g) reaction and in a carrier free form using charged particle induced reactions. The most widely used accelerator production method is presently based on the 103Rh(p,n) reaction, followed by difficult chemical separation from the expensive target material. For alternative production methods the available data on cross sections, thick target yields on and for production of possible 135 contaminants are or completely absent or scarce. In our new series of measurements we investigated systematically and with reliable precision a variety of accelerator based production routes. Proton, deuteron and alpha induced reactions were studied on Rh, Pd, Ag and Cd targets. Numerous excitation functions were measured up to 80 MeV. Also useful for other applications (TLA, elemental analysis, etc). The thick target yields for 103Pd of the different production routes were calculated from our fitted excitation curves. Marginal production yields on Ru targets were measured in Jülich and will also be discussed. Theoretical calculations for all reactions studied using the ALICE-IPPE code (Obninsk group) and comparison with our experimental results were performed. 389 Environmental Radiochemistry Education at Clemson University T.A. DeVol, R.A. Fjeld, J. D. Navratil, J.T. Coates and A.W. Elzerman; Department of Environmental Engineering and Science, Clemson University, Clemson, SC 29634-0919. Environmental radiochemistry at Clemson University is a graduate-level focus area within the Environmental Engineering and Science Department. The environmental radiochemistry focus area was initiated in the Fall of 2000 as a joint effort among the Westinghouse Savannah River Company, the Department of Energy, and Clemson University. The Department of Energy continues to provide funds for student and post-doctoral support through the Radiochemistry Education Award Program. The most important objective of the environmental radiochemistry focus area is to produce graduates who have the requisite capabilities and skills in radiochemistry to meet manpower needs in the United States. An undergraduate enrichment program was instituted to stimulate interest in radiochemistry among promising Clemson University undergraduates and minority students from South Carolina State University in order to prepare them for graduate study in radiochemistry. Current research areas are the development and application of techniques for measuring radioactivity in environmental media and waste streams, identification and quantification of the geochemical processes that play a role in the subsurface transport of radioactive contaminants, particularly plutonium; and development of technologies for removing radioactive contaminants from waste streams. DETERMINATION OF CARBON, NITROGEN, AND PHOSPHORUS IN CATTAIL BY USING THERMAL NUETRON PROMPT GAMMA ACTIVATION ANALYSIS L. Zhao*1, L. Robinson1, E. A. mackey2, R. L. Paul2, R. R. Greenberg2. 1Environmental Sciences Institute, Florida A&M University, Tallahassee, FL32307, USA. 2Analytical Chemistry Division, National Institute of Standards and Technology, Greenberg, MD 20899, USA. A method for the determination of carbon, nitrogen, and phosphorus in cattail using cold neutron prompt gamma activation analysis (CNPGAA) has been developed in the CNPGAA facility at the National Institute of Standards and 390 136 Technology (NIST), and evaluated through the analysis of Standard Reference Materials (SRMs) in previous studies. The results of numerous cattail samples using the CNPGNAA method show favorable comparison to results obtained by a CHNS/O analyzer for carbon and nitrogen. However, the results for phosphorus obtained by CNPGAA overestimated the results compared to those from a UV-VIS colorimetric method because of the effects of high chlorine content in cattails collected from an estuary. Therefore, a method for the determination of carbon, nitrogen, and phosphorus in cattails using thermal neutron prompt gamma activation analysis (TNPGAA) has been developed in the TNPGAA facility at NIST and evaluated through the analysis of SRMs, and compared to the results from CNPGAA. 391 DETERMINATION OF THE XENON BACKGROUND IN WESTERN EUROPE Guy BRACHET Commissariat à l‘Energie Atomique France. The radionuclide verification provisions of the Comprehensive Nuclear-Test-Ban Treaty include the measurement of xenon isotopes and this presentation relates to a study of the xenon background in Western Europe. Several SPALAX systems, the French equipment based on the separation of gases by membranes and charcoal followed by a gamma spectrometric measurement of the xenon isotopes, are implemented world-wide and in particular in Western Europe, where the density of nuclear activities is high. These xenon stations have daily measurements of some mBq of Xe-133 per cubic meter and from time to time peaks of several hundreds of mBq/m3 are registered. A methodology for estimating the xenon activity has been developed: wind field determination using NCEP data and the meso-scale model MM5, followed by the lagrangian dispersion model FLEXPART. The results are in a good agreement with the experimental measurements from the SPALAX and with the source terms of the releases from the nuclear civilian activities. The limitations of the source characterization by the isotopic ratio method, for discriminating between nuclear tests and civilian sources will be discussed as well as the extension of the SPALAX technology for measuring other noble gases besides xenon isotopes. 393 NUCLEAR, CHEMICAL, AND PHYSICAL CHARACTERIZATION OF NUCLEAR MATERIALS Lav Tandon, Elizabeth Hastings, Joseph Banar, James Barnes, David Beddingfield, Diana Decker, Doug Farr, John FitzPatrick, David Gallimore, Scott Garner, Russ Gritzo, Terry Hahn, Bill Johnson, Dan Knobloch, Stephen LaMont, Diana Langner, Cris Lewis, Rod McCabe, Patrick Martinez, Sandra Mecklenburg, Dave Mercer, Steve Meyers, Velma Montoya, Donivan Porterfield, Jane Poths, David Rademacher, Christy Ruggierio, Dan Schwartz, Khal Spencer, Robert Steiner, Heather Volz, Laurie Walker, and Amy Wong -- Los Alamos National Laboratory. The 137 goal of nuclear forensics is to establish an unambiguous link between illicitly trafficked nuclear material and its origin. Los Alamos National Laboratory has implemented a graded ―conduct of operations‖ type approach for determining the unique nuclear, chemical, and physical ―fingerprints‖ or signatures needed to identify the manufacturing process, intended use, and origin of interdicted nuclear material. In this study, an analysis flow path was developed for determining key signatures necessary for attributing an unknown material to a source. This process included both destructive (i.e., alpha spectrometry, ICPMS, ICPAES, TIMS, particle size distribution, particle fractionation) and non-destructive (i.e., gamma-ray spectrometry, autoradiography, optical microscopy, auger spectroscopy, electron probe, SEM, XRD, x-ray fluorescence) characterization techniques. Analytical results will be presented for a test ―unknown‖ sample characterized by this process along with an evaluation of the usefulness of this approach for nuclear material attribution. 394 CHARACTERIZATION OF DEPLETED URANIUM OXIDES FABRICATED USING DIFFERENT PROCESSING METHODS Elizabeth P. Hastings, Cris Lewis, John FitzPatrick, Dave Rademacher, and Lav Tandon -- Los Alamos National Laboratory. In nuclear forensics, the ability to identify key signatures in interdicted Special Nuclear Materials (SNM) is essential to rapidly identify a sample‘s characteristics, such as origin, intended use, and route attribution. To determine what key signatures exist in nuclear materials processed by different methods, a series of depleted uranium oxides fired at various temperatures have been analyzed. Differences that are evident range from physical appearance to the particle size distribution. For example, upon initial observation of the uranium oxide powders, a distinct difference in their coloring is observed. In this study, depleted UO2, UO3, and U3O8 fired at three temperatures ranging from 350-1100°C are compared based on non-destructive and destructive techniques that include the material density, particle size distribution, optical microscopy, and elemental composition (Inductively Coupled Plasma – Mass Spectrometry). Each analysis is performed at the bulk sample level followed by particle fractionation (cascade impactor) and analysis of each individual size fraction. ON THE DETECTION OF RARE, AND MODERATELY RARE, EVENTS: SOME ANCIENT HISTORY AND MODERN DILEMMAS Lloyd A. Currie, National Institute of Standards and Technology, Gaithersburg, MD 20899-8370. Some of the most interesting developments in science and commerce have resulted from attempts to detect rare events, such as related to the production of radiocarbon in the natural environment, the occurrence of dodder seeds in clover, and the early "counting" of solar neutrinos. These and far more recent examples share two issues in common: the need to meet an often predetermined detection capability, and the general applicability of Poisson counting statistics. Therein lies the dilemma. As 395 138 events become rarer, the commonly applied Poisson-normal approximation for "simple counting" becomes poorer. An underlying question in this respect is, "How far may we stretch the Poisson-normal approximation, before it breaks?" One finds that there are at least three different answers, and a special opportunity for excessive false positives, depending on the way the approximation is employed. The issue is made moot by reverting to the exact Poisson formulation, but now although the significance test (detection decision) is made without approximation, the detection limit cannot be rigorously specified without knowledge of the "true value" of the background (or environmental baseline). That leads to the core of the lowlevel detection problem: faulty assumptions about the stability and distribution of the background. Illustrations will be drawn from the historical literature as well as NIST work on low-level counting of 14C and noble gas radionuclides. 398 PREPARATION OF AMERICIUM TARGETS FOR NUCLEAR CHEMISTRY EXPERIMENTS AT DANCE Evelyn Bond (1), Alice Slemmons(2), John R. FitzPatrick(2) and Dave Vieira(1). (1) - Group C-INC, Los Alamos National Laboratory. (2) Group C-AAC, Los Alamos National Laboratory. Using 1 gram of 241Am from LANL stocks, we describe the purification steps required to obtain a purified solution of 241Am from the original material. Part of the purified solution was submitted for purity analysis by mass spectrometry and radiochemistry. The impurities were expected to be 239Pu and 237Np. A second fraction of the purified material was used for electroplating of three samples onto titanium disks that were suitable for insertion into an instrument package to be placed into the DANCE detector. We will discuss the purification methods used, the electroplating setup and the solutions to various problems that we encountered in making these targets. The results of the purification steps based upon the analytical results are discussed as well as the yields from the electrodeposition process. Comparison of these yields with those from similar experiments utilizing 235U and 243Am are discussed as well. NEUTRON ACTIVATION ANALYSIS AND X-RAY RAYLEIGH SCATTERING OF HAIR AND NAIL CLIPPINGS AS NONINVASIVE MONITORING TECHNIQUES REDUCING THE BURDEN OF ANIMAL TESTS Peter Bode(a), Maria Izabel Maretti Silveira Bueno(b), Gisele G. Bortoleto(b,) Gaby Hoffmann(c), Jan Rothuizen(c); (a) Delft University of Technology, Reactor Institute Delft, Delft, The Netherlands; (b) Instituto de Quimica, Universidade Estadual de Campinas, Campinas, SP, Brazil; (c) Department of Clinical Sciences of Companion Animals, Faculty of Veterinary Medicine, Utrecht University, The Netherlands. . The heritability of chronic hepatitis in, amongst others, the Labrador 399 139 retriever is studied at the Department of Clinical Sciences of Companion Animals at the Utrecht University in The Netherlands. This research is supported by the Cu determination in liver biopsies using INAA. As the project deals with companion animals and not with test animals, cooperation of the dog owners is crucial. Such cooperation can easier be obtained if the owner feels comfortable that the experiments will be of no harm to his dog. Therefore, a feasibility study was undertaken to assess the usefulness of nail clippings and hair (fur) as a non-invasive indicator for the Cu liver levels, aiming at a replacement for the transcuteaneous (i.e. through the skin) full needle biopsy. Liver biopsy samples, nail clippins and fur were collected from dogs with chronic hepatitis as well as from healthy animals. Nail clippings were taken from phalanx I (the thumb nail) since this nail is not in contact with the ground, thus minimizing contamination problems. Fur was sampled from the median abdominal wall, just cranial to the belly button. Cu and other elements were determined in all samples using INAA. The fur samples were also examined using X-ray Rayleigh scattering as it had been demonstrated before that the shape of the spectrum of Rayleigh scattered radiation has been shown [1] to reflect the organic components of the object analysed. Thus, the hypothesis could be tested if the melanin content of the hair is affected by the Cu metabolism. The Cu levels in biopsy, nail and fur have been compared, and principal component analyses have been carried out on the dataset of Cu biopsy levels and Rayleigh spectra. Results will be presented, with a discussion on the feasibility of using nail and fur in combination with the two techniques as reliable non-invasive, animalfriendly indicator for its trace element status. [1] Maria Izabel Maretti Silveira Bueno,T, Martha T.P.O. Castro, Aline Moreira de Souza, Erica Borges Santana de Oliveira, Alete Paixão Teixeira, ―X-ray scattering processes and chemometrics for differentiating complex samples using conventional EDXRF equipment‖, Chemometrics and Intelligent Laboratory Systems (2005) in press 400 TOP-DOWN VERSUS BOTTOM-UP ESTIMATES OF UNCERTAINTY IN INAA RESULTS. Peter Bode (a), Elisabete A.De Nadai Fernandes(b), Marcio A.Bacchi(b), (a) Delft University of Technology, Reactor Institute Delft, Delft, The Netherlands; (b) Centro de Energia Nuclear na Agricultura, Universidade de São Paulo, Piracicaba, Brazil. The initial publication of the ISO Guide to the Expression of Uncertainty in Measurement (GUM) and many related documents has resulted in a worldwide awareness of the importance of a realistic estimate of the value reported after the +/- sign. The evaluation of uncertainty in measurement, as introduced by the GUM, is derived from the principles applied in physical measurements. Many testing laboratories have already experienced large problems in applying these principles in e.g. (bio)chemical measurements, resulting in time-consuming evaluations and costly additional experiments. Other, more pragmatic and less costly approaches have been proposed to obtain a realistic estimate of the range in 140 which the true value of the measurement may be found with a certain degree of probability. One of these approaches, the ‗top-down method‘, is based on the use of the intra-laboratory reproducibility. This approach is much easier for tests for which it is either difficult to establish a full measurement equation, or if e.g. matrix-matching reference materials are absent. It has been demonstrated that the GUM ‗bottom-up‘ approach of evaluating uncertainty in measurement can easily be applied in instrumental neutron activation analysis (INAA) as all significant sources of uncertainty can be evaluated [1,2]. INAA is therefore a valuable technique to test the validity of the top-down approach. In this contribution, examples of the top-down evaluation of uncertainty in INAA derived from analyses of (certified) reference materials, participation in intercomparison rounds and BIPM pilot studies and key-comparisons will be presented. The results will be compared with the bottom-up evaluation of uncertainty. Ease of applicability, validity and usefullness of both approaches will be discussed. [1] P.Bode, E.A.De Nadai Fernandes, R.R.Greenberg, J.Radioanal.Nucl.Chem. 2000, 245, 109; [2] J. Kucera, P. Bode, V. Štepánek, J.Radioanal.Nucl.Chem. 2000 245, 115 401 RAPID SEPARATION OF LOW-YIELD ISOTOPES FROM FRESH FISSION MATERIAL Donald E. Dry. The amount of specific isotopes generated in the fission process is dependent, among other parameters, upon the type of fuel fissioned. The greatest differences in production are at the wings and valley of the fission yield curves. Yields of isotopes of Ag, Cd, Sm, Eu, and Tb, for example, can differ by orders of magnitude between fuels. In addition to low fission yield, analysis for these isotopes is further complicated by short halflives and/or low branching ratios, making quantification by gamma spectrometry difficult on fresh fission material. However, if the low-yield isotopes are separated from Ce isotopes, and the parent-daughter pairs of 140Ba/140La and 132Te/132I, quick detection is possible. LANL recently irradiated a highly enriched uranium foil and conducted experiments to validate a rapid analytical method for analysis of these low-yield isotopes. The information presented will be a continuation of work presented at MARC VI. LA-UR-05-9335. DETERMINATION OF ISOTOPE RATIO IN NATURAL ISOTOPES USING MALDI TOF MASS SPECTROMETRY Josef Havel a, b, Zbyněk Špalt a, b, Gracian Tejral a, and Shaban Elosta a. a Department of Analytical Chemistry, Faculty of Science, Masaryk University, Kotlářská 2, 611 37 Brno, Czech Republic; b Laboratory of Plasma Physics and Plasma Sources, Faculty of Science, Masaryk University, Brno, Kotlářská 2, 611 37 Brno, Czech Republic. Isotope ratio of various natural isotopes, (e.g. 235U/238U) is important for environmental radioactivity monitoring e.g. to follow the release of uranium from nuclear facilities and of naturally occurring radioactive materials by the coal, natural gas, minerals, ores, oil, fertilizer industries, etc. and also for studies on the 402 141 biogeochemical behavior of uranium in the environment, in archeology or astronomy for dating purposes, but also for the determination of samples origin, like food. Mostly, ICP MS is used but in this work the possibilities of soft ionization MALDI TOF mass spectrometry are examined. The isotope ratio can be determined from signals of pure atoms, clusters or from multielemental molecular peaks of various chemical compounds. Several examples concerning uranium, selenium, potassium, rubidium, and carbon (bulk δ 13C and δ 13C of individual compounds) materials are shown and discussed. The new software was developed to facilitate the quantification of isotopic ratio from various types of mass spectra. The applications concerning evaluation of mass spectra for uranium, sulfur, potassium, rubidium, carbon, elements or compounds in various matrices are presented and discussed. 404 MANAGING KNOWLEDGE – A KEY TO SUSTAINABILITY IN NUCLEAR DEVELOPMENT Y.Yanev, International Atomic Enegy Agency, Department of Nuclear Energy. Preserving and enhancing nuclear knowledge is vital to the continued, sustainable and safe utilization of all nuclear technologies for peaceful purposes. A recognized, current threat to nuclear knowledge is declining interest in the wide scale use of nuclear energy. This is exacerbated by a marked decline in the number of appropriately qualified young nuclear professionals to sustain and further develop the accumulated nuclear knowledge and expertise until such a time as this situation is redressed. While any nuclear resurgence is not a foregone conclusion, the loss of institutional memory of nuclear knowledge in governments, organizations and research institutes could become the precursor of problems in nuclear safety and in non-proliferation. Loss of nuclear expertise could also negatively affect future potential to apply nuclear techniques and methods in important areas such as medicine, agriculture, hydrology and food preservation, especially in developing countries. Therefore, the decline in the number of younger people studying nuclear sciences and a growing number of universities giving up their nuclear education programs have given rise to understandable concerns and requires attention. In a similar vein, education on nuclear disarmament and non-proliferation is already considered important in the context of strengthening disarmament and non-proliferation awareness in future generations. In the last three years the primary focus of the Agency‘s "knowledge management initiative" has been on working with the Member States to better understand their needs in managing nuclear related knowledge and information, both in terms of succession planning and knowledge preservation. The meeting of Senior Officials in June 2002, called by the DG, the Scientific Forum in 2003 and the Nuclear Knowledge Management International Conference in September 2004 in Saclay, France have marked important milestones in developing the Agency approach to knowledge management. The results and achievements of the Agency‘s ―nuclear knowledge management initiative‖ have been receiving wide 142 support and appreciation from the Member States, expressed in successive General Conference resolutions, statements in the BoG and in international meetings. The paper describes the strategic framework and actions for further developing nuclear knowledge management activities by the Agency. In doing this it deals with the main challenges and opportunities for nuclear knowledge management and the role of IAEA and in particular with (1) The Agency‘s Knowledge Management Model, (2) How the Agency knowledge management activities are expected to enhance the ability of the Member States to make full use of nuclear technologies for their economic and social development (3) How knowledge management will strengthen the position of the Agency as a widely recognized, independent, competent and authoritative source of information and knowledge for the peaceful, safe and sustainable use of nuclear technology. 405 Neutron energy spectrum determination and flux measurement using MAXED, GRAVEL, and MCNP for RACE experiments Authors: Taylor Green, Steven Biegalski, Sean O'Kelly. Organization: The University of Texas at Austin. Stainless steel flux wires were used to determine the neutron energy spectra and total flux during the ReactorAccelerator Coupling Experiments Project (RACE) at The University of Texas at Austin. A linac electron accelerator produced 20 MeV electrons at a power of 1.6 kW, which struck a tungsten-copper target to produce bremsstralung radiation and photoneutrons. The neutrons produced in the target were multiplied by the subcritical core of a TRIGA reactor. The purpose of the RACE experiments is to develop a subcritical accelerator driven system that would be capable of transmuting actinides from spent fuel. Flux measurements were made with 1.58 mm diameter stainless steel wires placed throughout the core between the fuel rods and cadmium covered and uncovered gold and indium foils above the target. The MAXED and GRAVEL computer codes were used to perform the spectrum unfolding. The composition of the stainless steel wires was determined using the comparative method prior to the flux measurement. The reactions measured in the stainless steel to determine the flux were 50Cr neutron absorption to 51Cr, 58Ni neutron proton to 58Co, 54Fe neutron proton to 54Mn, and 58Fe neutron absorption to 59Fe. Flux measurements agreed well with an MCNP simulation of the experiment. SUPERCONDUCTING ULTRA-HIGH ENERGY RESOLUTION GAMMA AND FAST-NEUTRON SPECTROMETERS S. Friedrich, S. Ali, S. F. Terracol, O. B. Drury, I. D. Hau, T. R. Niedermayr, Lawrence Livermore National Laboratory; U. Roy, A. Burger, Fisk University. Superconducting photon and particle detectors have been developed over the last decades because of the exquisitely high energy resolution that detector operation at temperatures below 1K enables. One 406 143 detector technology uses a superconductor operated at the transition between its superconducting and its normal state as a sensitive thermometer, and infers the photon or particle energy from the temperature rise upon absorption. These so-called transition-edge sensors (TESs) can be configured as Gamma- or as fast-neutron spectrometers with a choice of the appropriate absorber crystal. We are developing Gamma- and fast-neutron spectrometers based on Mo/Cu multilayer TESs, as well as the readout electronics and the adiabatic demagnetization refrigerators for user-friendly detector operation at ~0.1K. Our Gamma spectrometers use ~mm3 Sn foil absorbers, and have achieved an energy resolution between 50 and 90 eV for Gamma-rays below 122 keV. Our fast-neutron spectrometers use ~cm3 enriched 6LiF single crystal absorbers, and currently offer an energy resolution of ~50 keV for MeV neutrons This talk will give an overview about our cryogenic detector program, with special emphasis on the recent results for fast-neutron spectrometers. These spectrometers not only offer high energy resolution and several percent detection efficiencies for MeV neutrons; they also make discrimination of neutron and Gamma signals straightforward, since fastneutron energies are shifted in the spectrum by the Q-value of the (n,α) absorption reaction; and their simple response function makes spectral deconvolution comparably easy. We discuss spectrometer performance in the context of nuclear analysis, as well as the current development of large arrays for increased active area and total count rates. 407 URINE RADIOBIOASSAY INTERCOMPARISON RESULTS FROM THE INTERCOMPARISON STUDIES PROGRAM AT OAK RIDGE NATIONAL LABORATORY N. Bores, A. Denton, G. Payne, J. Rankin - Oak Ridge National Laboratory. The Intercomparison Studies Program (ISP) at the Oak Ridge National Laboratory (ORNL) provides natural urine QA/QC samples to the radiobioassay community. The samples are available as double blinds and are spiked at low levels (0-250 mBq/kg for alpha emitters) with common analytes of interest to the radiobioassay community. The goal of the program is to evaluate the entire analytical system of a participating laboratory by incorporating natural matrix samples into the routine workload. The resulting data reflects actual laboratory performance and is complimentary to more formal performance testing (PT) programs. Sample preparation and program results are presented and discussed. DETERMINATION OF PU-238, PU-239 AND PU-240 IN URINE AT THE MICROBECQUEREL LEVEL USING THERMAL IONIZATION MASS SPECTROMETRY: STUDY RESULTS N. Bores, A. Denton, G. Payne, J. Rankin - Oak Ridge National Laboratory. The Intercomparison Studies Program (ISP) at the Oak Ridge National Laboratory (ORNL) provided the Los Alamos National Laboratory (LANL) with a series of natural urine radiobioassay samples containing 238Pu, 239Pu and 240Pu isotopes at the µBq level. Sample preparation and analytical 408 144 results are presented and discussed. 409 Collision and reaction cells in atomic mass spectrometry: “chemical resolution” of isobaric and polyatomic ion interferences in radiochemical measurements Gregory C. Eiden, David W. Koppenaal, and Charles J. Barinaga, Pacific Northwest National Laboratory. Previous reviews of the development and utilization of collision and reaction cells in atomic mass spectrometry are updated with a focus on radionuclide detection and quantitation by mass spectrometry. Collision cells have been used for decades in fundamental studies of ion–molecule chemistry and have only recently been widely applied in analytical mass spectrometry. Such cells are used to promote reactive and non-reactive collisions, with resultant benefits in molecular ion interference reduction, isobar separation, and thermalization and focusing of ions. Novel ion–molecule chemistry schemes, using a variety of reaction gases selected on the basis of thermodynamic and kinetic principles and data, are now designed and empirically evaluated with relative ease. Surveys of the reactivity of atomic cations generated by an inductively coupled plasma ion source are being conducted to supplement earlier databases of reaction constants. A significant body of applications has now been reported in the literature. Collision/reaction cell techniques are found to be most useful for specialized or difficult detection needs, such as those encountered in ultratrace radiochemical measurements. We will review these topics and the state of this field with a focus on selected isotopes of interest in radiochemistry. CONTENT OF U, Pu, Am, AND Cm IN LIQUID RADIOACTIVE WASTE OF OBJECT “SHELTER” OF CHERNOBYL NPP O.O. Odintsov, Institute for Safety Problems of NPP, National Academy of Scienes of Ukraine, Chernobyl, 07270, Ukraine. Determination of specific activity of radionuclides 234-238U, 238Pu, 239+240Pu, 241Am, and 244Cm in liquid radioactive waste (LRW) of Chernobyl NPP Object ―Shelter‖ is the regulation task of radiation monitoring and control of Object ―Shelter‖. The methods of simultaneous determination of U, Pu, Am, and Cm from single sample of LRW of Object ―Shelter‖ are presented. Concentration of LRW samples is carried out by evaporation. Uranium, plutonium, americium, and curium are separated into anion-exchange resin Dowex 1x 8 in Cl— - form from 9 M HCl. Americium and curium are concentrated on cation exchanger Dowex 50 x 8 in H+ - form. Determination of activity of isotopes of uranium, plutonium, americium, and curium was carried out by high-resolution alpha-spectrometric measurements, after electrodiposition on stainless steel disks. 242Pu, 243Am and 232U are used as a tracers. DETERMINATION OF U, Pu, Am CONTENT IN GROUND WATER NEAR OBJECT “SHELTER” SITE 410 411 145 O.O. Odintsov, Institute for Safety Problems of NPP, National Academy of Scienes of Ukraine, Chernobyl, 07270, Ukraine. One of the most important tasks of ecological monitoring is the control for radionuclides content in water. Determination of specific activity of radionuclides 234,235,236,238U, 238Pu, 239+240Pu and 241Am in ground water is required to estimate the influence on environment of Chernobyl NPP Object ―Shelter‖. Concentration of ground water samples is carried out by evaporation. Determination of activity of isotopes of uranium, plutonium, americium, and curium was carried out by alpha-spectrometric measurements, after ion-exchange separation. 242Pu, 243Am and 232U are used as a tracers. The report contains the results of 234,235,236,238U, 238Pu, 239+240Pu, 241Am contents in ground water samples selected within local zone of Object ―Shelter‖. Volume activity of 238Pu, 239+240Pu , and 241Am in ground water are n • 10 –4 - n • 10 –1 Bq/dm 412 ALPHA SPECTROMETRIC DETERMINATION OF URANIUM IN LIQUID RADIOACTIVE WASTE OF OBJECT “SHELTER” O.O. Odintsov, Institute for Safety Problems of NPP, National Academy of Scienes of Ukraine, Chernobyl, 07270, Ukraine. A high volume of water with uranium and transuranium radionuclides is presented at Chernobyl NPP Object ―Shelter‖. This water is medium-active liquid radioactive waste (LRW). Determination of radionuclides 234,235,236,238U in LRW is required to estimate nuclear and radiation safety of Chernobyl NPP Object ―Shelter‖. Concentration of LRW samples is carried out by evaporation. Uranium was sorbing on anion-exchange resin Dowex 1 x 8 in Cl— form from 9 M HCl, and than eluting by 0.1 M HCL. Determination of activity of uranium isotopes was carried out by alpha-spectrometric measurements, after electrodiposition on stainles steel disks. 232U is used as a tracer. Results of determination of uranium in LRW from Object ―Shelter‖ are presented. Volume activity of 234U, 235U, 236U and 238U in LRW samples of Object ―Shelter‖ ranges from n • 101 to n • 103 Bq/dm3 USING THE RESULTS OF GAMMA-SPECTROMETRY MEASUREMENTS IN BOREHOLES TO DETERMINE THE MECHANISM OF RADIOACTIVE CONTAMINATION OF GROUNDS А.K. Каlynovsky, O.O. Odintsov, V.A. Krasnov. Institute for Safety Problems of NPP, National Academy of Scienes of Ukraine, Chernobyl, 07270, Ukraine. Under the results of gamma-logging data analysis performed in boreholes near Object ―Shelter‖, anomalous increase of gamma-radiation intensity was detected at the levels of anthropogenic preChernobyl and natural grounds, which are located lower than Chernobyl "active" layer. The ―active‖ layer is associated with interval of depths, at which dose rates exceed the level of natural background tens thousand times due to its contamination with highly radioactive fragments of the destroyed 413 146 reactor. A field gamma-spectrometry device with removable detectors on the basis of NaI(Tl) and BGO crystals was developed to study this phenomenon. Analysis of the carried out gamma-spectrometry measurements showed that the increase of gamma-radiation intensity in the investigated boreholes is caused by the surface (casing pipe) contamination with 137Cs. The ratio of 1274 keV 154Eu and 662 keV 137Cs full energy peak intensities was found to be close to the ratios typical for the vicinity of the ―active‖ layer and to the experimental ratios obtained for the Chernobyl reactor fuel with average burnup. Hence, the increase of gamma-radiation intensity can be associated with moving down of radioactive particles from the "active" layer during drilling and the natural migration of radionuclides from the ―active‖ layer to the ground water is not observed on the surveyed site. 414 SELECTIVE DISSOLUTION OF CHERNOBYL SEDIMENTS Heather M. Dion 1, Stephen P. LaMont 1, David Hayes 2, James Cadieux 2, Paul Bertsch 3; 1 Los Alamos National Laboratory; 2 Savannah River National Laboratory; 3 Savannah River Ecology Laboratory. A selective dissolution study of contaminated sediment collected near the Chernobyl nuclear reactor complex was completed to determine if it was possible to identify the presence of different chemical species of the same radionuclide. In contrast to total dissolution or strong acid leach methods in which elemental speciation is lost, selective dissolutions target radionuclides associated with specific soil constituents, for example ion-exchange sites or organic matter. A series of selective dissolution experiments were undertaken to understand the effects of aging on contaminant sequestration, and determine if these methods could be used to deconvolute multiple releases of radionuclides into the environment based on their associations with different soil constituents. Samples were taken from a recently drained cooling pond in the Chernobyl exclusion zone. For comparison, sediment from the Department of Energy‘s Savannah River Site was also examined. A standard selective dissolution scheme targeting the readily ionexchangeable fraction, iron and manganese oxide bound fraction, organic matter bound fraction, acid-leachable fraction, and residual fraction was conducted. Extracts were analyzed for specific fission products, uranium, and plutonium. Preliminary results indicate that 137Cs was differentially bound in the two samples, which is indicative of both a difference in initial contaminant input (particles vs liquid discharge) and aging time. 147