Abstract: The invention involves a process for production of macrostructures of a microporous material. The process is characterized by the fact that seeds formed in or introduced by ion exchange or adsorption to a porous organic ion exchanger with the desired size, shape and porosity are made to grow and form a continuous structure by further deposition of inorganic material from a synthesis solution under hydrothermal conditions. The organic ion exchanger can be eliminated by chemical destruction or dissolution and, in so doing, leaves behind an inorganic microporous structure with the size and shape of the employed organic ion exchanger.

Abstract: A method of preparing beta-spodumene bodies from a plastic batch comprised entirely of minerals, absent a glass component. The resulting structure has a stoichiometry of 1:1:4 (Li2O:Al2O3:SiO2) to 1:1:11 (Li2O:Al2O3:SiO2), and exhibits a low coefficient of thermal expansion, high porosity and high strength, and is suitable for automotive catalytic converter substrates requiring a fast light-off time. There is also provided a ceramic article having a solid-solution of beta-spodumene ranging in molar ratio from 1:1:4 Li2O—Al2O3—SiO2 to 1:1:11 LiO2—Al2O3—SiO2 wherein a component selected from the group consisting of magnesium oxide (MgO), manganese oxide (MnO), and cobalt oxide (CoO) is substituted for lithium oxide (LiO2) at 10 to 65 mole %, and optionally a minor phase of mullite (3Al2O3-2SiO2) in an amount of up to 50% by weight.

Abstract: A ceramic article is disclosed which contains aluminum, silicon, and titanium in a total amount of at least 99% by weight as reduced to the oxides (Al2O3+SiO2+TiO2) and assumes an acidic color in methyl red, an indicator of at least pKa+4.8. It can be used as a carried for a catalyst. This ceramic article is obtained by mixing an aluminum compound, a silicon compound, and a titanium compound and calcining the resultant mixture at a temperature in the range of 1,000°-2,000° C. A catalyst for preparing ethylene oxide is obtained by depositing silver and a reaction promoter on the ceramic carrier and ethylene oxide is obtained by oxidizing ethylene with a molecular oxygen-containing gas in the presence of the catalyst in vapor phase.

Abstract: The present invention relates to a zirconia based sintered body excellent in durability, characterized in that in Y2O3-toughened zirconia based sintered body, (a) ZrO2 contained therein is mainly composed of tetragonal ZrO2, and the sintered body contains Y2O3 as a secondary component and further SiO2 and Al2O3 as a third component; (b) the sintered body has a molar ratio of Y2O3/ZrO2 in the range of 1.5/98.5 to 4/96; (c) the sintered body has a SiO2 content of 0.05 to 2.5 wt %; (d) the sintered body has a Al2O3 content of 0.05 to 3.0 wt %; (e) the sintered body has an average crystal grain diameter of 0.7 ?m or less; (f) SiO2 (wt %)×average crystal grain diameter (?m) takes a value ranging from 0.03 to 0.5; (g) the sintered body contains at least one oxide of Na2O, K2O, CaO and Fe2O3 as an impurity and a weight ratio of SiO2/(total amount of the impurity) is 5 or more; and (h) the sintered body has a bulk density of 5.

Abstract: The present invention provides a low temperature fired porcelain comprising crystalline phases including sanbornite, celsian and ?-cristobalite phases when measured by a high power X-ray diffractometer. The ratio of the peak intensity of (101) plane of ?-cristobalite phase to the peak intensity of (101) plane of sanbornite phase is not higher than 5%. The porcelain is of a low temperature fired porcelain of silica-alumina-barium oxide system with cristobalite phase precipitated, in which the incidence of cracks in the porcelain may be reduced.

Abstract: Provided is a catalyst formulation which exhibits extended catalyst life. The formulation comprises a mixture of a ceramic foam material uniformly interspersed between the solid catalyst particles, with the volume percent of ceramic material in the mixture preferably ranging from 20 to 60 volume %. The catalyst formulation is particularly applicable to solid catalyst particles comprised of a phosphoric acid impregnated substrate, and is particularly useful for processes such as catalytic hydrocarbon condensation processes.

Abstract: The present invention provides a filler which has high water resistance and high acid resistance, and high releasing abilities of ions such as fluorine ions, and can maintain high aesthetic appreciation for a long period of time, and a dental composite material comprising the filler, excellent in water resistance, acid resistance, ion releasability and aesthetic appreciation.

Abstract: A dielectric ceramic article precursor and a process for preparing a dielectric ceramic article are presented. The ceramic article precursor comprises a crystalline aluminosilicate zeolite or an amorphous aluminosilicate, a zinc oxide additive and a glass phase. The ceramic article precursor can optionally contain at least one forming aid selected from binders, plasticizers and surfactants. The process for preparing a dielectric ceramic article involves forming a mixture from the above components into a shaped article such as a tape and then calcining the shaped article at a temperature of about 700° C. to about 1000° C. for a time of about 0.5 to about 24 hours.

Abstract: A brick additive and methods for using the brick additive are disclosed. The additive may include an internal porosity. The internal porosity may display an intra-granular internal porosity in which at least some of the pores are interconnected via an open network of pore spaces. In some embodiments, the additive is capable of maintaining its internal porosity after undergoing thermal modification via calcination, for example. In addition, brick additives of the present invention may display a large surface area.

Abstract: A cordierite ceramic body having (i) a pore size distribution and a porosity which satisfy the relationship 10.2474/[(d50)2(pore fraction)]+0.0366183(d90)?0.00040119(d90)2+0.468815(1/pore fraction)2+0.0297715(d50)+1.61639(d50?d10)/d50?3.65, and (ii) a CTE (25°-800° C.) of ?15×10?7/° C., wherein the cordierite ceramic body is produced from a moldable mixture comprising cordierite-forming raw materials including (a) a fine talc having a median particle diameter, as measured by laser diffraction, of less than 10 micrometers, and a B.E.T. specific surface area of greater than 5 m2/g, and (b) a pore former. The cordierite ceramic body is suitable in the fabrication of cellular, wall-flow diesel particulate filters having a low pressure drop, high filtration efficiency and improved strength.

Abstract: A preparation method of silica, especially superfine silica, with water glass and carbon dioxide as major raw materials in a carbonization reaction conducted under a high gravity field, typically in a Higee reactor.

Abstract: A ceramic material, includes SiO2 and Na2O and/or K2O. The material is characterized by a porosity of over 60% and by pores, more than 70% of which have a pore size ranging between 0.1 and 15 &mgr;m. The ceramic material can be used as filtering material, for water storage and as adsorbent material.

Abstract: A honeycomb structure constituted by cell partition walls (ribs) which form combined cells being composed of a plurality of cells adjacent to each other, and a honeycomb outer wall surrounding and holding outermost cells located at the circumference of combined cells, characterized in that cell partition walls and the honeycomb outer wall are formed by a bonded texture containing silicon carbide (SiC) as an aggregate and cordierite as a binder, and that the proportion (volume %) of silidon carbide (SiC) forming the bonded texture to the total of cordierite and silicon carbide (SiC) is 40 to 90%. This honeycomb structure can exceed required levels, in all of thermal conductivity, chemical durability, low thermal expansion and mechanical strength, producible at a low cost, and suitably used in a filter for purification of automobile exhaust gas, a catalyst carrier, etc.

Abstract: A material usable for the electrodes and the dielectric layer plasma display panels and capable of reducing the occurrence of yellowing and a high-image-quality plasma display panel using the material are provided. Using glass powder containing 25 to 50 wt % of Bi2O3, 5 to 35 wt % of B2O3, 10 to 20 wt % of ZnO, 5 to 20 wt % of BaO, 0 to 15 wt % of SiO2 and 0 to 10 wt % of Al2O3, the electrodes and the dielectric layer of a plasma display panel are formed.

Abstract: A thermal insulation molding having a density of 150-500 kg/m3, includes a thermal insulation material, containing 5%-75% by weight of pyrogenic silica (HDK), 5%-50% by weight of electric-arc silica, 5%-50% by weight of opacifier, wherein the electric-arc silica has a bulk density of <200 kg/m3, a carbon content of <0.1% by weight, an alkali metal oxide content of <0.2% by weight, an alkaline-earth metal oxide content of <0.3% by weight, an SO3 content of <0.05% by weight and a specific surface area of >30 m2/g.

Abstract: A thermoset polymer has a repeating unit comprising at least one crosslinking group having at least one unsaturated carbon-carbon bond and at least two crosslinking bonds, at least one borate group, at least one silyl group and/or at least one siloxyl group. The thermoset polymer of the present invention may be prepared by reacting a first compound having at least one alkynyl group, and at least one group selected from silyl groups and siloxyl groups, with a second compound selected from boric acid, hydrocarbon boronic acid, hydrocarbon borate, and pyroboric acid under reaction conditions sufficient to crosslink a sufficient number of alkyne bonds to form the thermoset polymer. The thermoset polymer of the present invention possesses both the processability of an organic polymer and the thermal and oxidative stability of an inorganic polymer. The thermoset polymer of the present invention may be further processed into a ceramic material by pyrolysis.

Abstract: Hyperbranched organometallic polymers, including poly [1,1′-ferrocenylenesilynes], poly [1,1′-ferrocenylene-(alkyl)silynes], poly [1,1′-ferrocenylene(alkenyl)silynes] and poly [1,1′-ferrocenylene(aromatic)silynes], are useful as precursors to certain ceramic materials. Processes for the preparation of such polymers and the preparation of ceramic materials from such polymers are described, as are the resulting ceramic materials and their use as ferromagnetic materials and electrically conductive materials.

Abstract: A silica-based photocatalyst fiber having visible-light activity, which fiber comprises a composite oxide phase comprising an oxide phase (first phase) mainly made of a silica component and a titania phase (second phase), wherein the second phase contains a metal element other than titanium and the existent ratio of the second phase slopingly increases towards the surface of the fiber, and a process for the production thereof.

Abstract: Ceramics comprising filler crystal particles having an average particle diameter of not smaller than 2.5 &mgr;m and a matrix crystal phase present on the grain boundaries of the filler crystal particles, the filler crystal particles being Al2O3 and the matrix crystal phase being diopside-type oxide crystals precipitated from the crystallized glass. The ceramics has a dielectric loss tangent at 60 to 77 GHz of not higher than 50×10−4, and can be effectively used as an insulating substrate in a wiring board for transmitting high-frequency signals.

Abstract: Methods of producing doped and undoped yttrium aluminum garnet and yttrium aluminum perovskite containing powders and the powders produced thereby are provided. Additionally, methods of forming doped and undoped polycrystalline yttrium aluminum garnet having a mean grain size of between about 1 &mgr;m to about 3 &mgr;m and the yttrium aluminum garnet produced thereby are provided. The doped and undoped polycrystalline yttrium aluminum garnet may be formed by sintering a compact and subsequently hot isostatically pressing the compact.

Abstract: A honeycomb structure made of a silicon carbide-based porous body and having a number of through-holes extending in the axial direction, separated by partition walls. The strength and Young's modulus of the silicon carbide-based porous body satisfy the following relation: Strength (MPa)/Young's modulus (GPa)≧1.1. The honeycomb structure contains refractory particles such as silicon carbide particles and the like and yet can be produced at a relatively low firing temperature at a low cost, has a high strength and a high thermal shock resistance, and can be suitably used, for example, as a filter for purification of automobile exhaust gas by a treatment such as plugging of through-channel at its inlet or outlet, or as a catalyst carrier, even under a high SV condition.

Abstract: An integrated ceramic module is formed of a first ceramic dielectric layer containing a glass as a sintering agent and having a high dielectric constant and high Q value, formed with an electronic component, and a second ceramic dielectric layer containing a glass as a sintering agent and having a low dielectric constant and a high Q value, formed with a signal transmission line.

Abstract: Electrically active devices are formed using a special conducting material of the form Tm—Ox mixed with SiO2 where the materials are immiscible. The immiscible materials are forced together by using high energy process to form an amorphous phase of the two materials. The amorphous combination of the two materials is electrically conducting but forms an effective barrier.

Abstract: Dispersions of pyrogenic oxides, doped using an aerosol, are prepared by mixing the oxide with a suspending agent and milling. The dispersions can be used to prepare inkjet paper.

Abstract: Pyrogenically prepared silicon dioxide with the following physicochemical properties: 1. Average particle size (D50 value)D50≧150 nm (dynamic light scattering, 30 wt %) 2. Viscosity (5 rpm, 30 wt %) &eegr;≦100 m·Pas 3. Thixotropy of Ti (&eegr;(5 rpm))/(&eegr;(50 rpm))≦2 4. BET surface area 30-60 m2/g 5. Compacted bulk=100-160 g/L 6. Original pH≦4.5 can be used for the preparation of dispersions and glass bodies.

Abstract: A ceramic carrier and ceramic catalyst body used as NOx purification catalysts for lean burn engines, which are inexpensive, exhibit high temperature durability and can maintain their catalytic function for extended periods. The ceramic carrier has a diffusion-inhibiting layer formed on the surface of a cordierite honeycomb structure, to inhibit diffusion of alkali metals, alkaline earth metals, etc. carried as NOx storage materials. The diffusion-inhibiting layer is composed of a ceramic material such as Y2O3, NiO or CeO2 which does not react with alkali metals or alkaline earth metals at temperatures of up to 1000° C. and has a melting point of higher than 1000° C., and the diffusion-inhibiting layer inhibits diffusion of catalyst components such as potassium into the interior to prevent their reaction with cordierite, so that the durability is greatly enhanced without reducing catalytic performance.

Abstract: A novel multipurpose mineral composition capable of emitting a large quantity of far infrared rays, negative ions and oxygen heat is manufactured by setting up an iron railing, an iron rod and an iron plate on a brazier, placing a tinfoil on the iron plate, and layering yellow soil, kaolin, sericite, and biomineral in sequence on the tinfoil, while inserting the tinfoil between the layers, loading a pulverized elvan in the furnace, pulverizing a mixed stone including 40 wt % of germanium, 15 wt % of true marine, 30 wt % of zeolite, and 15 wt % of franklin, to the particle size under about 44 &mgr;m, and loading the pulverized mixed stone in an internal furnace which is made by winding a copper plate with a tinfoil and placed on the plurality of layers of the furnace, heating the pulverized mixed stone at about 1,000° C. for about seven days into a lump, and repulverizing the lump.

Abstract: A glass for covering electrodes, which consists, as represented by mass percentage based on the following oxides, essentially of: Mass percentage PbO 44 to 68% Bi2O3 0 to 18%, B2O3 19 to 23%, SiO2 1.2 to 5%, Al2O3 2 to 6%, ZnO 4 to 9%, CuO 0.1 to 0.5%, In2O3 1.1 to 2%, SnO2 0 to 1%, and CeO2 0 to 1%.

Abstract: Disclosed is calcium metasilicate having an aspect ratio (average major axial diameter/average minor axial diameter) of from about 1:1 to about 2.5:1, and an oil absorption of from about 20 ml/100 g to about 220 ml/100.

Abstract: Disclosed is calcium metasilicate having an aspect ratio (average major axial diameter/average minor axial diameter) of from about 1:1 to about 2.5:1, and an oil absorption of from about 20 ml/100 g to about 220 ml/100.

Abstract: A photocatalyst article exhibits high photocatalytic activity even in environments illuminated by weak ultraviolet light or visible light, expresses excellent anti-fogging and anti-soiling properties, and retains good anti-fogging and anti-soiling performance over long periods and therefore has a high utilization value as an anti-fogging, anti-soiling article. The photocatalyst article contains an oxide semiconductor and a compound which contains at least one type of element selected from the group comprised of Mg, Sc, V, Cr, Mn, Y, Nb, Mo, Ru, W, and Re, at a content such that the ratio (A/B) of the number of metal atoms of the abovementioned element (A) to the number of atoms of metal that comprise the abovementioned oxide semiconductor (B) will be about 0.20 to 2.

Abstract: Compositions for use as thermal insulation or barriers in articles that are required to function under transient elevated temperature conditions, such as are experienced during a fire. Articles in which compositions according to the invention may be used include electrical and optical cables which have fire resistant properties, electrical fittings such as terminals and cable clips, and void-filling compounds which are required to act as fire barriers. The invention provides a composition that is ductile or flexible at the elevated temperatures experienced during a fire and retains integrity so as to stay in place throughout the fire enabling it to continue to function as a thermal barrier.

Abstract: The invention concerns a crack-free insulating refractory material made from a composition comprising 20-80% by weight of a ceramic matrix, 5-40% by weight of insulating microspheres, 0.5-15% by weight of one more binders, 5-20% by weight of a metal or a metal alloy able to melt during the preheating or the first minute of use and 0-25% by weight of water. The ceramic matrix is preferably comprised of vitreous and non-vitreous grains.

Abstract: A thermal insulation molding having a density of 150-500 kg/m3, includes a thermal insulation material, containing 5-75% by weight of pyrogenic silica (HDK), 5%-50% by weight of electric-arc silica, 5%-50% by weight of opacifier, wherein the electric-arc silica has a bulk density of <200 kg/m3, a carbon content of <0.1% by weight, an alkali metal oxide content of <0.2% by weight, an alkaline-earth metal oxide content of <0.3% by weight, an SO3 content of <0.05% by weight and a specific surface area of >30 m2/g.

Abstract: Disclosed is a metal sulphide coating composition of the formula MXSiVRYSZFW where M is one or more metals selected from: Mo, Ti, W, Nb, Ta, Zr, and Hf; Si is silicon; R is one or more elements selected from: C, B, Al, V, Cr, Fe, Co, Ni, Sm, Au, Cu, Zn, Sn, Pb, N, H, and O; S is sulphur; F is fluorine; X is 0.2 to 1.5; V is 0.02 to 3; Y is 0 to 4; Z is 0.2 to 6; and W is 0.01 to 6, and in which X, Y, Z, V, and W are given in amounts by atomic ratio. The compositions show good non-stick properties, low hydrophilia, and high stability.

Abstract: A method of making a cristobalite-free, mullite grain capable of withstanding reaction with molten aluminum, comprising the steps of: producing a clay slurry comprised of water and kaolin clay of a specific particle size; mixing a water insoluble barium or strontium containing compound into the clay slurry in an amount wherein the barium or strontium containing compound content of the slurry is equal to about 8% by weight of the kaolin clay in the slurry; removing sufficient water from the slurry to form a material having an pelletizable consistency; forming the material into pellets; heating the pellets by continuously moving them through a furnace having a zone, wherein the material is exposed to temperatures of at least 2,650° F. (1,455° C.) for at least 30 minutes.

Abstract: The invention provides a slurry composition suitable for the manufacture of Si3N4 sintered bodies, wherein the dispersion properties and oxidation resistance of Si powder in water are improved, resulting in the homogenous dispersion of a sintering aid powder and a fine Si powder with less oxygen. Si powder, a sintering aid, water in an amount of 50 to 90 wt % relative to the total weight of the composition, and a surface coating agent in an amount of 0.05 to 10 wt % relative to the Si powder are added, the pH is adjusted to between 3 and 8, and the ingredients are milled and mixed. Trivalent metal ions such as Fe or Ga, or a polysiloxane with a BHL of no more than 10 is used as the surface coating agent. The resulting slurry composition can be used to prepare Si3N4 sintered bodies with better electrical, thermal, and mechanical properties.

Abstract: A process of making ceramic spheroids by firing clay spheroids comprising by weight percent: FeO (3.22-5.21), Fe3O4 (3.40-5.11), SiO2 (52.49-59.42), CaO (1.99-7.96), MgO (2.81-4.69), Al2O3 (12.05-17.65), TlO2 (0.58-0.71), MnO (0.07-0.19), Na2O (0.47-0.86), K2O (1.70-2.37), P2O3 (0.13-0.19), S (0.03-0.29), CO2 (0.90-8.23), Organic C (0.22-1.04), H2O+ (4.14-7.28), H2O− (2.12-5.48) in contact with a particulate parting agent selected from aluminum oxide, magnesium oxide, and their precursors at a sufficiently high temperature and for a sufficiently long time to form a shell. Preferably, the clay spheroids are obtained from a deposit located at Hallock in Kittson County Minn., U.S.A.

Abstract: To provide an optically transparent film containing 0.01 to 20% by weight glass forming oxide consisting of Nb2O5, V2O5, B2O3, SiO2, and P2O6; 0.01 to 20% by weight Al2O3 or Ga2O3; and 0.01 to 5% by weight hard oxide of ZrO2 and TiO2 as required; balance being ZnO, and a sputtering target for forming such a film. This sputtering target reduces occurrence of particles during sputtering, decreases the number of interruption or discontinuance of sputtering to improve production efficiency, and forms a protective film for optical disks with large transmittance and low reflectance.

Abstract: A piezoelectric ceramic composition and a piezoelectric element in which cracks and chips are not likely to occur during working even if the thicknesses are reduced, are provided. The piezoelectric ceramic composition contains as a primary component, a complex oxide having a perovskite structure, composed of at least Pb, Zr, Ti, Mn, Nb and O, and represented by general formula ABO3, in which the total molar quantity of elements constituting A is smaller than the total molar quantity of elements constituting B, and Si is present as a secondary component at the content of about 0.010 wt % to 0.090 wt %, in terms of SiO2, relative to the primary component.

Abstract: An object of the invention is to provide a low temperature fired porcelain having an optimum firing temperature not higher than 1000° C., a reduced dielectric constant &egr; r, an improved quality coefficient and a low incidence of cracks.

Abstract: A composite material has a quartz glass phase and a complex compound phase compounded with the quartz glass phase, which is made of one or more compounds selected from a group of silicon carbide, silicon nitride, silicon, titanium nitride and titanium carbide, as a main ingredient. The composite material can be used instead of quartz glass, and can prevent the generations of microcrack, tipping and particles after the mechanical working.

Abstract: A new microporous crystalline molecular sieve material having the formula Cs3TiSi3O95•3H2O and its hydrothermally condensed phase, Cs2TiSi6O15, are disclosed. The microporous material can adsorb divalent ions of radionuclides or other industrial metals such as chromium, nickel, lead, copper, cobalt, zinc, cadmium, barium, and mercury, from aqueous or hydrocarbon solutions. The adsorbed metal ions can be leached out for recovery purposes or the microporous material can be hydrothermally condensed to a radiation resistant, structurally and chemically stable phase which can serve as a storage waste form for radionuclides.

Abstract: A sintered ceramic for a scintillator having a composition represented by the general formula of Gd3-xCexAlySizGa5-y-zO12, wherein 0.001≦x≦0.05, 1≦y≦4, and 0.0015≦z≦0.03, is produced by mixing gadolinium oxide, aluminum oxide, gallium oxide, a cerium salt, a silicon compound and a fluorine compound in such proportions as to provide the above composition; calcining the resultant mixture at a temperature of 1400-1600° C.; disintegrating the resultant calcined body to ceramic powder; pressing the ceramic powder to provide a green body; and sintering the green body at a temperature of 1600-1700° C. in a non-oxidizing atmosphere at 5×104 Pa or more, and optionally further by hot isostatic pressing at a temperature of 1400-1600° C. in an argon atmosphere.

Abstract: The present invention provides a Mn—Zn ferrite having an electrical resistivity exceeding 1 &OHgr;m order and a low core loss in a high frequency region exceeding 1 MHz. A basic component composition of the Mn—Zn ferrite includes 44.0 to 49.8 mol % of Fe2O3, 6.0 to 15.0 mol % of ZnO (15.0 mol % is excluded), 0.1 to 3.0 mol % of CoO, 0.02 to 1.20 mol % of Mn2O3, and the remainder of MnO. The Mn—Zn ferrite achieves desired purposes by controlling Fe2O3 content to a range less than 50 mol % that is the stoichiometric composition, adding a proper amount of CoO, restraining amount of Mn2O3 formation to 1.20 mol % or less, and further setting their average grain sizes to less than 10 &mgr;m.

Abstract: The present invention provides a Mn—Zn ferrite having an electrical resistivity exceeding 1 &OHgr;m order and having a low core loss in a high frequency region exceeding 1 MHz. The basic component composition of the Mn—Zn ferrite includes 44.0 to 49.8 mol % Fe2O3, 6.0 to 15.0 mol % ZnO (15.0 mol % is excluded), 0.1 to 4.0 mol % at least one of TiO2 and SnO2, and remainder MnO, wherein desired results are obtained by limiting Fe2O3 content to less than 50 mol % that is the stoichiometric composition and adding a proper amount of TiO2 or SnO2 and further controlling its average grain size to less than 10 &mgr;m.

Abstract: Acicular bodies of a metal compound are produced by slowly precipitating an organic salt of the metal from a solution of an ester of a dicarboxylic acid having 1-5 carbon atoms and firing the precipitate in an oxidizing atmosphere. These acicular bodies have a cross-sectional dimension less than about 20 &mgr;m and are useful for providing reinforcement of a larger ceramic body. Acicular bodies of rare-earth metal oxides also are useful in reinforcing x-ray scintillator bodies without diminishing their luminescent capacity.

Abstract: A member used within a plasma processing apparatus and exposed to a plasma of a halogen gas such as BCl3 or Cl2 is formed from a sintered body of metals of Group IIIa of Periodic Table such as Y, La, Ce, Nd and Dy, and Al and/or Si, for example, 3Y2O3·5Al2O3, 2Y2O3·Al2O3, Y2O3·Al2O3 or disilicate or monosilicate, and in particular, in this sintered body, the content of impurity metals of Group IIa of Periodic Table contained in the sintered body is controlled to be 0.15 wt % or more in total. Specifically, for this member, an yttrium-aluminum-garnet sintered body having a porosity of 3% or less and also having a surface roughness of 1 &mgr;m or less in center line average roughness Ra is utilized.

Abstract: The present invention is a method of manufacturing low carbon content (hence, an off-white color), amorphous (non-crystalline) siliceous ash from ordinary siliceous waste materials such as, for example, rice hulls, and plant residues from biogas generation. A portion of plant waste materials is pyrolyzed in a furnace such as a tube furnace. Next, the material is pyrolyzed in a tube furnace at a temperature of between about 500 and 800° C. for at least 0.5 hours to 3 hours. Simultaneous to the pyrolysis, a continuous stream of air is passed over the material, and gaseous products from the pyrolysis are drawn off. The siliceous ash is thus formed.

Abstract: A sintered ceramic honeycomb article that exhibits an average linear coefficient of thermal expansion (25-800° C.) below about 5.0×10−7° C.−1, a total porosity between the range of 20% to about 30%, and a pore size distribution such that at least about 86% of pores are of a pore size of less than about 2 &mgr;m with the pores exhibiting a generally elongated shape oriented with their long axis in the plane of the webs, the article being made from a cordierite-forming inorganic powder batch comprising a platy talc having median particle of size less than about 2 &mgr;m, at least 4% by weight of a dispersible Al2O3-forming source having a specific surface area in excess of 50 m2/g, and one or more of the components of kaolin, calcined kaolin, silica, and corundum, each having a median particle sizes less than 5 &mgr;m.