TL-And-PL-Study-Of-Beta-Irradiated-Calcite-Collected-From-Semaria-Mines-Of-C.G.-Basin

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					Jamonline / 2(4); 2012 / 292–300                                                 Vikas Dubey et al

Research Article

Journal of Atoms and Molecules
An International Online Journal
ISSN – 2277 – 1247


  TL and PL Study of beta irradiated calcite collected from Semaria
                       mines of C.G. Basin
            Vikas Dubey(1) * ; Jagjeet Kaur(1); Suryanarayana N.S(1); K.V.R.Murthy(2)

1. Department of Physics, Govt. Vishwanath Yadav Tamaskar Post Graduate Autonomous College,
                                   Durg (C.G.), India, 491001
2. Applied Physics Department, Faculty of Technology and Engineering M.S. University of Baroda,
                                     Baroda 390001, India
Received on: 09-07-2012             Revised on: 29-07-2012           Accepted on: 24-08-2012
Abstract:

The present paper reports the photoluminescence (PL) and thermoluminescence (TL) studies of
natural calcite collected from Semaria mines of C.G. Basin. The sample was irradiated with Sr-90
beta source given a dose of 10Gy and the heating rate used for TL measurements are 6.660C/sec was
described. The sample displayed a good TL peak at 1270C and the corresponding activation energy
(E) values are calculated. Photoluminescence excitation spectrum at ~254 nm, the corresponding
emission spectrum peak at 395 nm is reported.


Keywords: Thermoluminescence; Photoluminescence; Kinetic Parameter.



                                                    Introduction:
      * Corresponding author                        A number of most common rock minerals

      Vikas Dubey,                                  including    Calcite,     dolomite,     aragonite,
       Email: jsvikasdubey@gmail.com,               magnesite,    anhydrite     and       quartz   are
           jagjeet_62@yahoo.co.in                   thermoluminescent. Impurity ions and other
      Phone: +91- 9826937919
                                                    crystal defects in these minerals provide
                                                    trapping levels and luminescence centres
                                                    which result in variety of glow curves for
                                                    crystal which are formed under different
                                                    condition.   Calcites   normally       incorporate
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Jamonline / 2(4); 2012 / 292–300                                                        Vikas Dubey et al

various impurities during crystallization. In           Materials and Methods:
the present investigation, an attempt was               The natural Calcite samples were collected
made to study the Thermoluminescence glow               from Semaria mines of C.G. Basin. Micron
curve characteristics and photoluminescence             size sample was prepared by grinding in a
of   crystalline        sample    collected      from   Pastle and Mortar. Sample pre annealed for 1
Chhattisgarh       mines.    It   has     promising     h at 2000C, and immediately cooled to room
applications in geological and archeological            temperature. The TL glow curve was recorded
dating and in radiation dosimetry. The                  by TLD Reader Model No. I1009 supplied by
Thermoluminescence (TL) of calcite has been             Nucleonix Sys. PVT. LTD., Hyderabad.
the subject of numerous intensive studies               Detail of TLD reader is reported elsewhere
because of the geological and archeological             [10]. The sample was irradiated with Sr-90
importance of this material [1]. Early studies          beta source given a dose of 10Gy and the
[1, 2] on the TL of various minerals include            heating rate used for TL measurements are
the presence of TL (afterglow) in aragonite             6.660C/sec        was       described.       The
(orthorhombic        CaCO3)       and      dolomite     photoluminescence        (PL)     emission    and
(CaCO3MgCO3). Medlin [3] investigated the               excitation spectra were recorded at room
calcite minerals in detail and attributed its TL        temperature    using     Spctrofluorophotometer
emission to Mn2+ centres. Nambi and Mitra               RF-5301 PC of SHIMADZU make. The
[4] have studied the TL of calcites of three            excitation source is a xenon lamp. The
different geneses and concluded that TL                 chemical composition analysis was done by
sensitivity is highest in the samples of                ELAN DRC II at NGRI - Hyderabad. The
hydrothermal       origin,   even       though    the   sample (calcite) was characterized at Inter
manganese (Mn) concentration is lowest in               University Consortium (IUC) Indore for X-
that sample. Franklin et al. attempted to               ray diffraction. XRD data were collected over
correlate TL with the genesis of natural                the range 200-700 at room temperature. X-ray
calcite crystals [5].                                   diffraction patterns have been obtained by
                                                        Rigaku        Rotating       Anode        (H-3R)
                                                        diffractometer.




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Jamonline / 2(4); 2012 / 292–300                                             Vikas Dubey et al




                    Figure 1 Mineral Resources of Chhattisgarh Geology Map




                      Figure 2 Thermo luminescence Analyzer type TL1009

Figure 3 a schematic diagram of a TL              system, the detection system and the signal
measuring instrument is represented. Three        processing. The most common heating system
main parts can be envisioned: the heating         is composed of a resistive planchet that heats

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Jamonline / 2(4); 2012 / 292–300                                               Vikas Dubey et al

up as a result of the passage of current          normally used to detect the emitted TL. In
through it. A common method of measuring          fact the efficiency of high – gain, very
the temperature is through the use of a           sensitive PMTs allow the detection of very
thermocouple welded to the underside of the       low level signals with a convenient signal – to
planchet. A photomultiplier tube (PMT) is         – noise ratio.




                      Figure 4 Diagram of a typical TL measuring system


Results and Discussion:                           measurements are 6.60C/sec. The sample
                                                  displays a good TL peak at 1270C and the
Fig 5 show the TL glow curve of Calcite
                                                  corresponding activation energy (E) values
collected from Semaria mines of C.G. Basin
                                                  are calculated using the formulas modified by
irradiated with beta (β) source given a dose of
                                                  Chen and others [6-9].
10 Gy. The heating rate used for TL




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Jamonline / 2(4); 2012 / 292–300                                                Vikas Dubey et al




                           Fig 5 TL glow curve of beta irradiated Calcite



  Beta
                                                       = activation Frequency
 irradia  T1      Tm       T2                          energy E        factor S in
   ted                                                     (eV)             (S-1)
 calcite 363     400      445 36        45    81     0.553       0.577           2X108
TABLE 1: shape factors (), Activation Energy E and Order of Kinetics b of beta irradiated natural
                     Calcite collected from Semaria mines of C.G. Basin



The peak shape factor for 1270C peak in
calcite sample was found to be 0.553 which
reflects that the order of kinetics is second.
The values of E and s derived from different
Chen’s peak shape methods tabulated in Table
1 & 2. The TL kinetics, the activation energy,
attempt to escape frequency of electrons in
the trap associated with 1270C were found to
be second order 0.557eV, 2x108 sec-1 and trap
depth   in      between   0.22   to   0.614   eV
respectively.

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Jamonline / 2(4); 2012 / 292–300                                                                    Vikas Dubey et al

                                             Methods                           References     Activation
                                                                                            energy in (eV)

                                        E (eV) = Tm(K)/500                         [6]      0.25

                                         ���� �������� = ��������������������                      [7]      0.25

                                         ���� �������� = ��������������������                      [8]      0.41

                                                   ����������������
                                                         ����                        [9]      0.614
                                         ���� �������� =
                                                      ����
                                              ������������
                                                  ����                               [9]      0.223
               �������� = ��������                             − ��������(2K�������� )
                                                ����

                                             ������������
                                                 ����                                [9]      0.407
               ���� = ����                               − ���� (2K�������� )
                                                

                                              ������������
                                                  ����                               [9]      0.381
               ���� = ����                               − ���� (2K�������� )
                                                


Table 2 The trap depth for the prominent glow peaks of the studied Calcite, evaluated from second
order kinetics
                Intensity (arb units)




                                                                  Wavelength (nm)
                                                             Fig 6 PL excitation spectra




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Jamonline / 2(4); 2012 / 292–300                                                Vikas Dubey et al




           Intensity (arb units)




                                         Wavelength (nm )

                                     Fig 7 PL emission spectra

   Fig 6 and Figure 7 are the PL excitation and emission spectrum of specimen. The excitation
 monitored at 400 nm wavelength shows peak at 254nm. The broad emission spectrum, peaking at
                           ~395nm is observed under both excitations.




                                   Figure 8 XRD pattern of calcite



The figure 8 (XRD pattern) confirms that the          were collected over the range 200-700 at
sample is calcite. The sample (calcite) was           room temperature. X-ray diffraction patterns
characterized at Inter University Consortium          have been obtained by Rigaku Rotating
(IUC) Indore for X-ray diffraction. XRD data          Anode (H-3R) diffractometer.

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Jamonline / 2(4); 2012 / 292–300                                            Vikas Dubey et al



                                           Conclusion:


                                           The value of activation energy E, frequency
                                           factor s for 1270C TL peak of β-irradiated
                                           calcite sample collected from Semaria mines
                                           of Durg district were higher when estimated
                                           using peak shape methods. The activation
                                           energy E, frequency factor s of the 1270C TL
                                           glow peak of calcite are 0.577 eV, 2x108sec-1
                                           and trap depth 0.22 to 0.614 eV respectively.
                                           The  value was found to be 0.553 which
                                           indicates second order kinetics for beta
                                           irradiated      calcite.         Photoluminescence
                                           excitation     spectrum     at    ~254   nm,   the
                                           corresponding emission spectrum peak at 395
                                           nm is found.


                                           Acknowledgement:


                                           We are grateful to UGC New Delhi for
                                           funding through a Major Research Project.
                                           Also very thankful to NGRI (National
                                           Geophysics Research Institute), Hyderabad
                                           for Chemical Analysis of our sample.




    Table 3 Chemical Analysis of Calcite




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Jamonline / 2(4); 2012 / 292–300                                             Vikas Dubey et al

References:                                     [5] Franklin A D, Hornyak W F, Pagonis V &
                                                Kristianpoller N, (1990) Nucl Tracks &
[1] Aitken M. J., (1985) thermoluminescence     Radiation Meas, 17 517.
Dating (Academic Press, New York), pp 204.      [6] Randall J.T. and Wilkins M.H.F., (1945) Proc.
[2] Visocekas R, Ceva T, Lapraz D, Iacconi P,   Roy. Soc. A 184 366.

& Lefaucheux F, (1973) Phys Status Solidi a     [7] Urbach F., (1930) Winer Ber. IIa 139 363.
                                                [8] Lushihik L.I., (1956) Soviet Phys. JEPT 3 390
, 15 61.
                                                [9] Chen R. (1969) J.Electrochem.Soc. 116: 1254.
[3] Medlin W L, (1968) in
                                                [10] Dubey Vikas, Suryanarayana N.S. and
Thermoluminescence of Geological Materials
                                                Kaur Jagjeet, (2010) Kinetics of TL Glow
(ED) D J Mc Dougall (Academic Press, New
                                                Peak of Limestone from Patharia of CG Basin
York), pp 193.
                                                (India). Journal of Minerals & Materials
[4] Nambi KSV & Mitra S,
                                                Characterization & Engineering, 9(12):1101-
(1978)Thermochim Acta, 27 61.
                                                1111.




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