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Process For Homo--or Copolymerization Of Conjugated Olefins - Patent 8153545
This invention relates to metal complex compositions, their preparation and their use as catalyststo produce polymers through (homo)polymerization of ethylenically unsaturated addition polymerizable monomers or through copolymerization of ethylenically unsaturated addition polymerizable monomers with at least one different type of ethylenicallyunsaturated addition polymerizable monomer. More particularly, this invention relates to metal complex compositions, their preparation and their use as catalysts to produce polymers of conjugated dienes through polymerization of conjugated ethylenically unsaturated addition polymerizablemonomers or through copolymerization of conjugated ethylenically unsaturated addition polymerizable monomers with at least one different type of ethylenically unsaturated addition polymerizable monomer. The used metal complex compositions are group 3 metal compounds including lanthanides and actinides, preferably lanthanide compounds, more preferably neodymium compounds in combination with activator compound(s) and optionally a catalystsupport. More particularly, the invention relates to metal complexes containing at least one metal-nitrogen or metal-phosphorus bond and in addition to it at least one metal halide bond, more particularly at least one metal-nitrogen bond and at least onemetal halide bond and to the preparation of the catalyst and the use of the prepared catalyst to produce homo- or copolymers of conjugated dienes, preferably through, but not limited to, through homopolymerization of 1,3-butadiene or copolymerization of1,3-butadiene with styrene or isoprene. More preferably the polydiene or the polydiene sequences of the copolymer consist predominantly of cis units. Polymers from conjugated ethylenically unsaturated addition polymerizable monomers and metal complex catalysts for producing the same are known. Knowledge of the molecular weight and molecular weight distribution of the polymer as well as the microstructure of the po
Optical Isomer Separating Filler - Patent 8153551
TECHNICALFIELD The present invention relates to an optical isomer separating filler having an excellent solvent resistance and separating ability, and more specifically, to an optical isomer separating filler in which a polysaccharide derivative is chemicallybonded to a support, the optical isomer separating filler having the following characteristic: a halogen content in the filler is 3.0% to 5.0%.BACKGROUND ART In recent years, the importance of optically active compounds has been significantly growing in the fields of, for example, medicine, agricultural chemicals, food, flavors, and liquid crystals. In particular, in the field of medicine, thefollowing facts have been known: only one optical isomer may show a pharmacological effect, there may be a difference in extent between the pharmacological effects of the optical isomers, or the pharmacological effects themselves may be different fromeach other. In view of such circumstances, it has been a serious problem to secure a needed optically active compound as inexpensively and stably as possible. Under the above-mentioned need, a technique for separating optical isomers by high performance liquid chromatography (HPLC) is expected to be one method of securing only a needed optically active compound inexpensively and stably. It has beenheretofore known that polysaccharide derivatives each have an excellent ability to separate optical isomers (for example, Patent Documents 1 and 2). Optical isomer separating fillers comprising the polysaccharide derivative have the following characteristics: each kind of the fillers can separate a large number of optical isomers and is excellent in general-purpose property. However, notall the optical isomers that exist in the world can be separated with one kind of an optical isomer separating filler, so the filler and optical isomer separating filler as described below have been developed: a filler having a separating ability bywhich optical isomers that cannot be separated wit
Gas Sorbing Composite Systems And Methods For Their Manufacturing - Patent 8153553
CROSS-REFERENCE TO RELATEDAPPLICATIONS This application is a Section 371 of International Application No. PCT/IT2006/000873, filed Dec. 22, 2006, which was published in the English language on Jul. 5, 2007, under International Publication No. WO 2007/074494 A1 and the disclosure ofwhich is incorporated herein by reference.BACKGROUND OF THE INVENTION The present invention relates to gas sorbing composite systems, as well as to methods for their manufacture. Gas sorbing systems and materials are widely used in industry in all applications where it is necessary to maintain a vacuum or to control the composition of the gaseous atmosphere by the removal of traces of undesired gases, particularly indisplays being used as screens for television, computers, or in many other electronic applications, such as hand held computers, mobile phones and the like. A particularly important case of displays is the OLEDs (Organic Light Emitting Diodes), beingdescribed for instance in U.S. Pat. Nos. 5,804,917 and 5,882,761, and in particular those belonging to the latest generation, known as "Top Emission OLED" (TOLED). In the latter, it is foreseen that the light leaves the device passing through thesurface which is opposed to the one where the system responsible for forming the image is located, that is from the surface most suitable for housing the getter system. In this case, the getter system obviously must be transparent. Because of theirimportance, particular reference will be made in the following to these latter type of displays, but the teachings of the invention have a more general applicability, for instance in the case of plasma screens. Gas sorbing materials used in industry are normally inorganic compounds in a finely dispersed form, in order to increase the specific surface (surface area per weight unit) and thus the capability and speed of interaction with the surroundinggaseous environment. Examples of these materials are alkaline-earth metal oxides, such as C
Method For Preparing Composites Of Zeolite-fiber Substrate - Patent 8153543
CROSS-REFERENCES TO RELATED APPLICATIONS This is a US National Stage of International Application PCT/KR2005/003594, filed Oct. 27, 2005, and published May 4, 2006, as International Publication WO 2006/046837 A1, the entire contents of which are incorporated herein by reference; andthe benefit of priority is claimed to Republic of Korea Patent Application No. 10-2004-0086048, filed Oct. 27, 2004, and published May 3, 2006, as Korean Unexamined Publication 10-2006-0036971 B1, the entire contents of which are also incorporatedherein by reference.BACKGROUND 1. Field The present invention relates to a method for preparing a composite of zeolite-tethering fiber substrate, particularly, to a method for forming a zeolite layer on s fiber substrate by use of sonication process. 2. Related Art Zeolite is a generic name of crystalline aluminosilicate, which constitutes the pore skeleton of zeolite molecules and bears an anionic charge for each aluminum atom. Cations for offsetting such anion charges are present within the pore spaceand the remaining pore space is filled with water. Where zeolite is heated for a given period of time at 200-300.degree. C., anions or water molecules are released, rendering it to accept other molecules into its pores. Such acceptance ability allowszeolite to have size selectivity or shape selectivity to certain molecules and thus zeolite is referred to as a molecular sieve. Zeotype molecular sieves generated by replacing a portion or all of silicon (Si) and/or aluminum (Al) atoms of a zeolite molecule are also widely used in the industrial field. For example, zeotype molecular sieves in which anions are replacedwith metal atoms serve as a catalyst for cracking petroleum. Besides, zeolites and zeotype molecular sieves have been reported to be useful as adsorbent, water-absorbing agent, gas-purifying agent, additives for detergent, ion exchanger, soil improvingagent and carrier for sensor. Zeolites and zeotype molecular sieves generally e
Method For Treating Flue Gas Catalysts - Patent 8153542
The instant application should be granted the priority date of Dec. 16, 2005 the filing date of the corresponding Europeanpatent application 05 027 634.4.BACKGROUND OF THE INVENTION The invention relates to a method for treating a flue gas catalyst base (substrate/carrier), including reactivating a catalyst base. In order to catalytically accelerate chemical reactions in fluid streams, one uses catalysts that are applied on or contained in catalyst bases. Usually, such bases comprise at least one contact area of a porous material. The surface that ismade of and enlarged by the porous material includes active centers favoring a reaction of the reactants carried by the fluid stream. The contact area is understood as a macroscopic boundary of the base material adjacent to the fluid stream. Thatcontact area is to be distinguished from the pore wall areas that have smaller, sometimes microscopic dimensions and are formed by areas defining the boundaries of the pore spaces/volumes. The pore wall areas of such pores leading into an opening in thecontact area form one surface with the contact area and enlarge the surface that is accessible by the fluid stream. The streaming fluid and the reactants (within the fluid) enter (diffuse) into the pore system that is formed by the pores; they come into contact with the active centers located at the pore wall areas and there they are adsorbed. In thisprocess, the reactants react and the reaction products are released by desorption and diffuse out of the pore system back into the fluid stream. Such catalyst bases are in particular used in processes, if exhaust gases are to be cleaned from undesiredsubstances carried within the gases, e.g. when cleaning the flue gas of combustion power plants. Burning fossil fuels (or waste and/or biomass) produces air pollutants. It is desirable to remove the air pollutants because of their negative effect on the environment. Apart from the dusts that can be removed from flue gas streams
Reversible Hydrogen Storage Materials - Patent 8153554
BACKGROUND Recently, considerable attention has been given to the use of hydrogen as a fuel or fuel supplement. While the world's oil reserves are being rapidly depleted, the supply of hydrogen remains virtually unlimited. Hydrogen is a relatively lowcost fuel and has the highest density of energy per unit weight of any chemical fuel. Furthermore, hydrogen is essentially non-polluting since the main by-product of burning hydrogen is water. However, while hydrogen has enormous potential as a fuel, amajor drawback in its utilization, particularly in automotive applications, has been the lack of an acceptable on-board hydrogen storage medium. Hydrogen storage in a solid matrix has become the focus of intense research because it is considered to be the only viable option for meeting performance targets set for such automotive applications. Although there are many technical targetsand design criteria surrounding a viable hydrogen storage system, four important targets appear to be system volume and weight, discharging and charging rates, thermal management associated with charging, and dormant system over-pressurization. It is common for many materials to release copious amounts of heat during charging. In this regard, it is extremely difficult, if not impossible, to fill an on-board storage system with hydrogen in a short period of time because of inadequatethermal management unless a complicated heat exchanger system is integrated into the on-board filling operation. Such a problem can be resolved with off-board refilling of an easily exchangeable canister. It is also common for many materials to releasehydrogen uncontrollably during minimal dormant heating. In this regard, it is very difficult, if not impossible, to prevent hydrogen from being vented to the environment to circumvent over-pressurization of the storage system during dormant heatingunless a complex on-board "hydrogen on demand" type system is integrated into the on-board storage system. However
Catalyst For Treating Exhaust Gas And Device For Treating Exhaust Gas Using The Same - Patent 8153549
This application is theU.S. National Phase application of PCT International Application No. PCT/JP2004/016230, filed Nov. 1, 2004, and claims priority of Japanese Patent Application No. 2004-301597, filed Oct. 15, 2004.FIELD OF ART The invention relates to an exhaust gas catalyst wherein a plurality of layers has been formed on a support.BACKGROUND ART The following may be listed as specific examples of exhaust gas catalysts for internal combustion engines and automotive engines in particular: oxidation catalysts for simultaneously treating hydrocarbon (HC) and carbon monoxide (CO) in exhaustgas; three-way catalysts for simultaneously treating the hydrocarbon, carbon monoxide and nitrogen oxides (NOx) in exhaust gas; NOx occlusion-reduction catalysts, wherein NOx is occluded from the exhaust gas at lean air-fuel ratio, the air-fuel ratio isswitched to the theoretical air-fuel ratio or a rich air-fuel ratio before the occluded NOx reaches saturation, and the NOx is thereby reduced; and NOx selective reduction catalysts that reduce the NOx in the exhaust gas by means of a reducing agent. Oxidation catalysts, three-way catalysts, NOx occlusion-reduction catalysts and NOx selective reduction catalysts are manufactured by making the catalyst components into a slurry, soaking onto a support such as a ceramic support of honeycombgeometry and calcining. In nearly all existing exhaust gas catalysts, however, the catalyst components are formed uniformly on the support; gas diffusion in the exhaust gas is therefore slow when the exhaust gas flows into the exhaust gas catalyst, and as a result theexhaust gas is often found to be incompletely treated. In view of this, Japan Patent Kokai No. 2002-191988 (Patent Reference 1) and Japan Patent Kokai No. 2002-253968 (Patent Reference 2) have proposed an NOx occlusion-reduction catalyst wherein the gas diffusibility of the exhaust gas is raised andthe NOx cleaning efficiency is enhanced by supporting a noble metal and NOx occludin
Isomerization Catalyst - Patent 8153548
1. Field of the Invention The present invention relates to catalysts for petroleum refining, and particularly to an isomerization catalyst for converting straight chain hydrocarbons, particularly C.sub.7 and higher paraffins, to branched hydrocarbons in order to improvethe octane rating of the feedstock. 2. Description of the Related Art Ever since the advent of the internal combustion engine, gasoline and diesel fuel have been valuable commodities. Gasoline is a blend of hydrocarbons having a boiling point between 30-200.degree. C. that is produced by distillation of crudeoil. However, straight-run gasoline is a poor fuel because of the phenomenon of engine knock, which occurs when a portion of the air-fuel mixture in the combustion chamber ignites prematurely. Premature detonation experienced during engine knock causesengine wear from vibration, and severe knock may damage the engine. It is known that engine knock is more severe with straight-chain hydrocarbons. Octane rating is improved with more branching in the hydrocarbons. One measure of the antiknock properties of gasoline is the octane number (diesel fuel uses asimilar rating called the cetane number). There are two octane numbers of interest: the research octane number (RON) determined by testing that simulates driving under mild, cruising conditions; and the motor octane number (MON) that is determined bytesting that simulates more severe conditions under load or at high speeds. In the U.S., the octane rating at the gas pump is the average of the RON and the MON. Heptane is assigned an octane rating of 0, while 2,2,4-trimethylpentane (isooctane) isassigned an octane number of 100. An engine performs best when the gasoline octane rating is matched to the compression ratio of the engine. Most gasoline refining uses some form of catalytic cracking of C.sub.11-C.sub.14 kerosene to light hydrocarbons in the C.sub.3-C.sub.5 range, followed by catalytic reformation of the light hydrocarbons to highl
Mixed Metal Oxide Ammoxidation Catalysts - Patent 8153546
REFERENCE TO RELATEDAPPLICATIONS This application is related to (i) U.S. patent application Ser. No. 12/661,716, entitled "Process for Preparing Improved Mixed Metal Oxide Ammoxidation Catalysts", filed Mar. 23, 2010, by Brazdil et al., and (ii) U.S. patent application Ser. No. 12/661,720, entitled "Attrition Resistance Mixed Metal Oxide Catalysts", filed Mar. 23, 2010, by Brazdil et al., both filed on the date even herewith, which are hereby incorporated by reference for all purposes.BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improved catalyst for use in the ammoxidation of an unsaturated hydrocarbon to the corresponding unsaturated nitrile. In particular, the present invention is directed to an improved catalytic composition forthe ammoxidation of propylene and/or isobutylene to acrylonitrile and/or methacrylonitrile, respectively. 2. Description of the Prior Art Catalysts containing oxides of iron, bismuth and molybdenum, promoted with suitable elements, have long been used for the conversion of propylene and/or isobutylene at elevated temperatures in the presence of ammonia and oxygen (usually in theform of air) to manufacture acrylonitrile and/or methacrylonitrile. In particular, Great Britain Patent 1436475; U.S. Pat. Nos. 4,766,232; 4,377,534; 4,040,978; 4,168,246; 5,223,469 and 4,863,891 are each directed to bismuth-molybdenum-iron catalystswhich may be promoted with the Group II elements to produce acrylonitrile. In addition, U.S. Pat. Nos. 5,093,299, 5,212,137, 5,658,842 and 5,834,394 are directed to bismuth-molybdenum promoted catalysts exhibiting high yields to acrylonitrile. In part, the instant invention relates to an improved bismuth-molybdenum-iron catalysts. Typically, such catalysts are produced in a batch process by simply combining and reacting, source compounds for the various metal components. However,more complex and multiple-step preparations have been used. For example, U.S.
Cement-based Composition For The Embedding Of A Boron-containing Aqueous Solution, Embedding Process And Cement Grout Composition - Patent 8153552
This application is a National Stageapplication of International Application No. PCT/EP2007/054779 filed May 16, 2007, the entire contents of which is hereby incorporated herein by reference. This application also claims the benefit under 35 U.S.C. .sctn.119 of French Patent Application No. 06 51823, filed May 18, 2006,the entire contents of which is hereby incorporated herein by reference.TECHNICAL FIELD The invention relates to a cement-based composition for the embedding (coating) of a boron-containing aqueous solution and to a process for the embedding by cementation of a boron-containing aqueous solution in which the said aqueous solution iskneaded, mixed with the said cement-based composition. The invention also relates to the cement-grout composition thus obtained. The boron-containing aqueous solution which can be embedded by cementation with the cement-based composition according to the invention, according to the grout formulation of the present invention, and by the process according to the invention,is in particular an aqueous solution with a high concentration of boron. This aqueous solution can in particular be composed of boron-comprising aqueous waste originating from industrial processes; for example, it may be aqueous wastes generated by thenuclear industry, such as an aqueous draining solution resulting from the draining, purging of the primary cooling circuit of pressurized water reactors. It should be specified that the term "grout" is a civil engineering term denoting a water/cement/sand mixture with a rheology favourable to flow. The term "embedded (coated) product" comes under the vocabulary used for the management of waste. It denotes a mixture of waste and optionally water (if the waste is not an aqueous solution)/cement/sand, without reference to the rheology after kneading, mixing. In the context of the invention, the terms "grout" and "embedded product" are generallyequivalent. The technical field of the invention may generally be
Process Of Manufacturing Oil Adsorption Foaming Sheet Using Peat Moss - Patent 8153550
The present invention relates to a process of manufacturing an oil adsorption foaming sheet for preventing pollution of the ocean or soil by oil or hydrocarbon, or recovering the ocean or soil polluted by oil or hydrocarbon, and moreparticularly to a process of manufacturing an oil adsorption foaming sheet using peat moss for preventing pollution of the ocean or soil by oil or hydrocarbon, or recovering the ocean or soil polluted by oil or hydrocarbon, in which a foaming compositeconsisting of soft polyurethane prepolymer mixed with peat moss from which stone, gravel, wooden pieces, and grass are removed and refined into a moisture-containing state and lecithin, is foamed to thereby obtain a block-shaped polyurethane foamingbody, the block-shaped polyurethane foaming body is sliced into sheets, and the sliced sheets is dried into a moisture content of 2 wt % or below.BACKGROUND ART As crude oil demand increases rapidly by fast progress of industry at recent years, oil exploration is lively performed, and crude oil transportation increases rapidly. Accordingly, an accident at sea by an oil outward flow would frequentlyoccur. As a result, fishes may fall dead and birds are fatally damaged. In addition, habitat of birds may decrease. Further, the soil and ocean may be polluted by exploration and drilling. The soil and ocean are gradually severely polluted by amalicious outward flow of industrial waste as well as an accident of leakage and rupture of oil pipage or storage tanks. A number of oil adsorbents and oil adsorption methods have been developed for such problem solution. There are hundreds of oil adsorbents which are currently used. The oil adsorbents are classified into ones for preventing oil pollution of theocean or recovering the soil polluted by oil, according to use. According, to ingredients of oil adsorbents, the oil adsorbents are classified into an inorganic adsorbent of porous mine such as zeolite, illite, and perlite, and clayey bentonite hav
Method For Preparing Non-metallocene Catalysts - Patent 8153544
The invention relates to ways to prepare non-metallocene catalysts useful for polymerizing olefins. The catalysts incorporate a tridentate dianionic ligand.BACKGROUND OF THE INVENTION While Ziegler-Natta catalysts are a mainstay for polyolefin manufacture, single-site (metallocene and non-metallocene) catalysts represent the industry's future. These catalysts are often more reactive than Ziegler-Natta catalysts, and theyproduce polymers with improved physical properties. The improved properties include controlled molecular weight distribution, reduced low molecular weight extractables, enhanced incorporation of .alpha.-olefin comonomers, lower polymer density,controlled content and distribution of long-chain branching, and modified melt rheology and relaxation characteristics. Traditional metallocenes incorporate one or more cyclopentadienyl (Cp) or Cp-like anionic ligands such as indenyl, fluorenyl, or the like, that donate pi-electrons to the transition metal. Non-metallocene single-site catalysts, including onesthat capitalize on the chelate effect, have evolved more recently. Examples are the bidentate 8-quinolinoxy or 2-pyridinoxy complexes of Nagy et al. (see U.S. Pat. No. 5,637,660), the late transition metal bisimines of Brookhart et al. (see Chem. Rev. 100 (2000) 1169), and the diethylenetriamine-based tridentate complexes of McConville et al. or Shrock et al. (e.g., U.S. Pat. Nos. 5,889,128 and 6,271,323). In numerous recent examples, the bi- or tridentate complex incorporates a pyridyl ligand that bears a heteroatom .beta.- or .gamma.- to the 2-position of the pyridine ring. This heteroatom, typically nitrogen or oxygen, and the pyridyl nitrogenchelate the metal to form a five- or six-membered ring. For some examples, see U.S. Pat. Nos. 7,439,205; 7,423,101; 7,157,400; 6,653,417; and 6,103,657 and U.S. Pat. Appl. Publ. No. 2008/0177020. In some of these complexes, an aryl substituentat the 6-position of the pyridine ring is also avail
Photocatalyst Material, Process For Producing The Photocatalyst Material, And Method For Decomposing Contaminant Using The Material - Patent 8153547
The present invention relates to a photocatalyst material, in particular, a photocatalyst material responsive to visible light. Further, the present invention relates to a process for producing the photocatalyst material. More, the presentinvention relates to a method for decomposing a contaminant using the photocatalyst material.BACKGROUND ART A photocatalyst has a high capacity of oxidizing and decomposing, for example, organic matters or apart of inorganic substances such as NOx. And, the light which is available at low cost and has a small environmental load may be used as anenergy source. Therefore, in recent years, the application of the photocatalyst to environmental clean-up, deodorization, antifouling, and sterilization has been advanced, and various photocatalysts have been developed and studied. Among them, the photocatalyst material responsive to visible light is expected, and thus, the study and development thereof have been progressed. For example, Patent document 1 discloses a photocatalyst responsive to visible light in which a halogenated platinum compound (0.01 to 1% by weight, calculated based on platinum) is supported on the surface of catalyst particles such as titaniumoxide. Patent document 1: Japanese Patent Application Laid-Open No. 2004-73910.DISCLOSURE OF THE INVENTIONProblems to be solved by the Invention However, although the photocatalyst material disclosed in Patent document 1 has a very small amount of platinum (0.01 to 1% by weight, calculated in platinum equivalent), the use of platinum in itself causes the high cost of the material. Further, the fact of needs for the photocatalyst responsive to visible light still remains. An object of the present invention is to solve the above-described problems and meet the needs. Specifically, the object of the present invention is to provide a photocatalyst material without using platinum, which may be produced at low cost, in particular, a photocatalyst responsive to visible light. In add
Subnanometer And Nanometer Catalysts, Method For Preparing Size-selected Catalysts - Patent 8148293
1. Field of the Invention This invention relates to subnanometer catalysts and methods for fabricating subnanometer and nanometer size-selected catalyst clusters, and more specifically, this invention relates to catalyst clusters comprising 4 to 20 atoms of catalyticmetal and methods of producing the clusters on a support substrate. 2. Background of the Invention Alkanes are typical feedstocks for transformation to alkenes, aromatics and chemicals containing value added moieties. Dehydrogenation is a route to such transformations but dehydrogenation is an endothermic process requiring significant energyinput. Oxidative dehydrogenation (ODH) of propane to propylene is a multibillion dollar industrial process. Two classes of catalysts are used: VOx and Pt-based. The vanadia based ones are highly selective but their activity is relatively low. Pt-based catalysts are more active but their selectivity is low. U.S. Pat. No. 6,781,018 issued to Liu et al. on Aug. 24, 2004 discloses the use of molybdenum and/or vanadium oxides for converting dimethyl ether to formaldehyde. ODH of alkanes is exothermic, and thus an attractive alternative to dehydrogenation. However, current ODH catalysts have limited activity and/or poor selectivity resulting from inability to prevent complete oxidation. For example, FIG. 1depicts a preferable reaction pathway "A" for propane undergoing oxidative dehydrogenation versus just as likely non-preferable reaction pathways "B", "C", "D", and "E". Silberova et al. Appl. Catal. A: General 276 17-28 (2004) discusses oxidative dehydrogenation of ethane and propane at short contact times. U.S. Pat. No. 5,623,090 issued to Haruta et al on Apr. 22, 1997 discloses catalysts comprising gold particles deposited on titanium oxide carrier. These catalysts were used to produce alcohol, ketone, and epoxides via oxidation ofhydrocarbons. U.S. Pat. No. 6,252,095 issued to Hayashi et al on Jun. 26, 2001 also utilizes gold particles to partially
Reticular Cordierite Composition, Article And Manufacture Thereof - Patent 8148297
FIELD This disclosure relates to porous cordierite material and porous cordierite articles having reticular microstructure, and methods of manufacture of the articles, and in particular extruded shaped articles, such as honeycomb shaped articles, thatcan be used, for example, as a catalyst support substrate or filter.BACKGROUND Cordierite has been used for a variety of applications such as catalytic substrates and filters for diesel particulate emission. Cordierite has low thermal expansion and is therefore suited for applications where high thermal shock resistanceis required. Cordierite shows anisotropy in its thermal expansion with the different crystallographic directions exhibiting positive and negative expansion. Due to the anisotropy in thermal expansion, mismatch strains build up between grains withdifferent crystallographic orientation, and such strains can lead to microcracking. Polycrystalline cordierite ceramics undergo extensive microcracking during thermal cycling. Microcracks open during cooling and heal during heating. This creates ahysteresis response in the thermal cycling behavior with differences between the heating and cooling curve that can be attributed to the presence of microcracks. As a result of the microcracking, the overall thermal expansion of the ceramics is loweredcompared to the crystallographic average CTE. In one sense, lowering the coefficient of thermal expansion (CTE) through microcracking is beneficial, as the thermal shock resistance of the material, which is proportional to the material's strength and inversely proportional to its elasticmodulus and thermal expansion, is expected to improve with microcracking. However, the material strength is significantly lowered with growing microcrack density, so that balancing fracture toughness, porosity, thermal expansion and strength becomesdifficult.SUMMARY In one aspect, a porous ceramic material is disclosed herein comprised of a principal cordierite phase, the porous ceram
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