Abstract: A producing method for producing zirconia hollow particles in which a zirconia powder mutually combines to form a porous shell layer thereby constructing a hollow structure, the method being characterized in mixing under a pressurized contact a resin powder and a zirconia powder of a grain size smaller than that of the resin powder, thereby forming a precursor by covering a surface of the resin powder with the zirconia powder in a partially embedded state, and calcining the precursor to expel the resin powder and to mutually sinter the zirconia powder.

Abstract: A process for preparing zirconium-cerium-based mixed oxides which comprises reacting an alkali with an aqueous solution of a zirconium salt containing 0.42-0.7 mole of sulphate anion (SO42?) per mole of zirconium cation at a temperature of not greater than 50° C., in the presence of a cerium salt to form a cerium-zirconium mixed hydroxide, and then calcining the cerium—zirconium mixed hydroxide to form a mixed oxide. The mixed oxides possess good thermal stability and are essentially single phase and are suitable as promoters and catalyst supports in, particularly, automobile exhaust systems.

Abstract: The present invention relates to silicon nitride mould parts, particularly crucibles for use in connection with directional solidification and pulling of silicon single crystals. The mould parts consist of Si3N4 having a total open porosity between 40 and 60% by volume and where more than 50% of the pores in the surface of the mould parts have a size which is larger than the means size of the Si3N4 particles. The invention further relates to a method for producing the silicon nitride mould parts.

Abstract: A method generating chlorine dioxide is provided. The method uses sodium chlorite solution and diluted sulfuric acid to generate chlorine dioxide with a significantly higher rate of conversion of chlorite to chorine dioxide than has been previously reported with sulfuric acid/chlorite chlorine dioxide generation.

Abstract: The invention concerns a method for producing a medium purity silicon comprising: preparing, by carbothermic reduction of silica in a submerged arc-furnace a silicon with low boron content; refining the liquid silicon with oxygen or chlorine; treating the refined silicon under reduced pressure from 10 to 100 Pa with neutral gas injection; segregated solidification. The invention also concerns a medium purity silicon designed to serve as raw material for making silicon of electronic or voltaic quality, and having (in weight fractions): a total of impurities ranging between 100 and 400 ppm, with the content in metallic elements ranging between 30 and 300 ppm; a boron content from 1 to 10 ppm; a phosphorus/boron ratio ranging between 0.5 and 1.5.

Abstract: Highly dispersed supported catalyst nanoparticles are manufactured at temperatures below about 95° C. The catalyst nanoparticles are formed on a support using an organic anchoring agent. The anchoring agent molecules include at least two functional groups. One functional group is selected to bond with the catalyst atoms and the other functional group is selected to bond with the support material. The anchoring agent and its interaction with the support provide a template for the catalyst atoms. The catalyst nanoparticles are manufactured by treating the support material with a solution of the anchoring agent. A solution of the catalyst atoms is reacted with the anchoring agent molecules to form an intermediate supported catalyst. The supported intermediate catalyst is dried by heating at a temperature less than about 95° C. In an alternative embodiment, the catalyst atoms are reacted with the anchoring agent molecules prior to treating the support material with the anchoring agent.

Abstract: A fluorine-doped tin oxide powder is prepared by combining a solution of a stannic salt with a solution of a fluoride, separating the tin hydroxide from the liquid and drying it at a temperature not exceeding about room temperature and heating the dried product to at least 500.degree. C., until the fluorine content is less than 10% and preferably is between 1 and 5% by weight. The fluorine-doped tin oxide powder of the invention can be used for the manufacture of electrically conductive toner powder.

Abstract: A process for producing a powder of perovskite-type double oxide comprises the steps of reacting water-soluble lead oxide and aqueous solution of alkaline metal in a reaction vessel, and precipitating lead group hydroxide; then adding a solution of Nb group, precipitating Nb group hydroxide, and reacting hydrothermally in the reaction vessel. As a result, according to the present invention, the process of manufacture is capable of producing fine particles of pure perovskite phase, which particles are excellent in homogeneity and the degree of sintering.

Abstract: The subject invention relates to a coated reinforcement material comprising a SiC reinforcement having an outer core coating of the general formula:Ti.sub.x M.sub.y B.sub.zwherein M is at least one of V, Nb, Ta, Cr, Mo, W, Zr, and Hf; x is between about 30 and 60 atomic percent; y is between about 5 and 30 atomic percent; z is between about 35 and 60 atomic percent; and x+y+z=100. The invention further relates to a high strength, high temperature performance composite comprising a ternary boride coated SiC reinforcement material and titanium alloy matrix material.

Abstract: A process is provided for obtaining high quality high surface area zinc oxide from a roasted zinc sulphide concentrate by leaching with an ammoniacal ammonium carbonate solution. The process utilizes optional preliminary oxidation and water leaching steps to remove soluble impurities and an optional aqueous sulphur dioxide leaching step to selectively remove readily soluble zinc oxide. The process includes an improved source of roasted zinc sulphide concentrate. The process also includes an optional reduced pressure calcining step to produce zinc oxide with further increased surface area.

Abstract: A process for producing stable, high purity ferrate (VI) employing beta-ferric oxide (beta-Fe.sub.2 O.sub.3), and preferably monohydrated beta-ferric oxide (beta-Fe.sub.2 O.sub.3 .multidot.H.sub.2 O) as the iron source. An improved process for producing stable, high purity beta-ferric oxide is also disclosed. The process results in the efficient and effective productions of ferrate with high yields and small amounts of waste production. A large portion of the unused product stream can be recycled to the ferrate reactor for the production of additional ferrate.

Abstract: An organic titanium compound and an organic compound which can react with the organic titanium compound, preferably a titanium tetraalkoxide and/or it derivative and methanol, are reacted in gas phase and the obtained product is hydrolyzed to give nearly real spherical, fine particle titanium oxide with no agglomeration and of mono dispersion.

Abstract: A tantalum carbide composite material comprises a tantalum carbide preform infiltrated with a low melting temperature metal selected from aluminum, copper, various alloys of either aluminum or copper, gold and silver.

Abstract: In a process for precipitating alumina hydrate from a stream of Bayer process liquor, wherein the stream is first divided into a major portion and a minor portion, the minor portion fed to an agglomeration stage and seeded with fine seed to induce precipitation and formation of a slurry, and the major portion cooled and charged with coarse seed and directed to a growth stage to induce formation of alumina hydrate product, the steps of: separating solids from the minor portion after formation of the slurry; cooling, to a temperature of between about 45.degree. C. and about 60.degree. C., the liquid remaining after separating solids from the slurry formed in the agglomeration stage; adding an amount of coarse seed to the remaining liquid to generate a slurry of fresh hydrate nuclei; and recombining the slurry of fresh hydrate nuclei with the major portion of the stream.

Abstract: An improved process for precipitating alumina from Bayer process liquors is disclosed. The process involves dividing an incoming pregnant liquor stream into a minor portion of about 10 to about 25% by volume of the total incoming pregnant liquor stream, and directing that stream into a series of small tanks where the minor stream is permitted to agglomerate. Fine aluminum hydroxide seed having a median particle size of between about 30 and about 60 microns is added to this stream. The slurry resulting from the agglomeration stage is then directed to a set of larger vessels in which the growth stage will take place. At this point, the remaining portion of the pregnant liquor is combined with the slurry resulting from the agglomeration stage. A coarse seed charge of about 150 to about 600 grams/liter of seed having a median particle size of between about 80 and about 100 microns is charged into the second set of vessels.

Abstract: An information recording medium is disclosed which records information through the transition of two phases of a recording material, utilizing electromagnetic wave energy. The information recording medium comprises a recording layer made up of a recording material of a composition represented by the formula:wherein6.ltoreq..alpha..ltoreq.138.ltoreq..beta..ltoreq.1718.ltoreq..gamma..ltoreq.2845.ltoreq..delta..ltoreq.66.alpha.+.beta.+.gamma.+.delta.=100.

Abstract: A method for the production of inorganic oxide particles by a procedure comprising the steps of dispersing inorganic oxide particles as seed particles in a water-containing alcohol solution thereby preparing a suspension of said seed particles and adding a hydrolyzable and condensable organic metal compound to said suspension thereby effecting growth of said seed particles, which method further comprises causing the presence in said water-containing alcohol solution of an alkylene glycol having 2-8 carbon atoms, in an amount in the range of 1 to 50% by weight, based on the amount of said water-containing alcohol solution.

Abstract: Needle-like electrically conductive zinc oxide filler having low specific volume resistance and excellent electrical conductivity-imparting effect per unit weight thereof is provided, including a method for its preparation.

Abstract: The spray drying of a solution containing hydrogen peroxide and sodium metaborate to obtain primary particles which are immediately conveyed after leaving the drying zone to a granulating device and are then granulated in the presence of free and/or perborate water of crystallization. The granulated materials are dried, if necessary. The generally amorphous primary particles are converted into granulated materials with at least partially crystalline structure and significantly improved shelf life. The work is performed with advantage in a spray dryer with integrated fluid bed or in a compressing granulating device. The method is suitable for preparing perborate granulated materials with an active oxygen content of over 10% by weight, especially perborate monohydrate granular materials with 14 to 16% by weight active oxygen. A rapidly dissolving product is produced with an acceptable apparent weight for ease in packaging.

Abstract: Potassium impurity is removed from ammonium molybdate by dissolving the ammonium molybdate in hot acid, allowing the acid solution to cool whereby the ammonium molybdate precipitates out of the solution as molybdenum trioxide and then separating, washing and drying the molybdenum trioxide.