Abstract: The present invention provides a method of making barium titanate powder. The method includes adding barium acetate to a solution of oxalic acid and titanium oxychloride to form barium titanyl oxalate and then calcining the barium titanyl oxalate to obtain barium titanate powder.

Abstract: The present invention provides a method of making barium titanate powder. The method includes adding barium acetate to a solution of oxalic acid and titanium oxychloride to form barium titanyl oxalate and then calcining the barium titanyl oxalate to obtain barium titanate powder.

Abstract: Titanium oxide particles are prepared from the reaction of an aqueous basic solution with (1) an aqueous acidic titanium salt solution, or (2) an aqueous salt solution of a titanium salt and an aqueous salt solution of a dopant metal salt. In preferred embodiments, the particles may range in size from 0.1 to 10 microns (10-6 meters), and possess relatively high bulk density combined with high surface area.

Abstract: Internal porosity is created in dense SiO.sub.2 particles by heating a mixture of the particles with B.sub.2 O.sub.3 at a temperature above about 450.degree. C. Resulting SiO.sub.2 particles have altered morphology, internal porosity, and small to negative volume changes when heated.

Abstract: A process suitable for producing high purity alkaline earth fluoride product is disclosed which involves (a) mixing (i) MgO, CaO, BaO, Mg(OH).sub.2, Ca(OH).sub.2, and/or Ba(OH).sub.2, (ii) NaOH, KOH and/or NH.sub.4 OH, and (iii) water, to form an aqueous slurry having a temperature of at least 20.degree. C. and an aqueous phase pH of at least 13; (b) adding fluosilicic acid, optionally adding additional water and optionally adding additional NaOH, KOH and/or NH.sub.4 OH to the slurry of (a) at a rate which maintains an aqueous phase pH of 11 or above, and in an amount to provide a molar ratio of Si: (Mg, Ca, and Ba) of at least 1:3.3, a molar ratio of (Na, K, and NH.sub.4):Si of at least 2:1, and a molar ratio of water:Si of at least 20:1, and to obtain a precipitate comprising an alkaline earth fluoride (MgF.sub.2, CaF.sub.2 and/or BaF.sub.2), and an aqueous solution of a soluble silicon anionic compound; and (c) recovering the alkaline earth fluoride product.

Abstract: Internal porosity is created in dense SiO.sub.2 particles by heating a mixture of the particles with B.sub.2 O.sub.3 above the melting point of both mixture components. Resulting SiO.sub.2 particles have altered morphology, internal porosity, and a negative thermal expansion coefficient when heated.

Abstract: Solution precipitation processes for preparing antimony doped tin oxide having improved volumetric efficiency and improved wash efficiency involving use of concentrated base and metal salt solutions are disclosed.

Abstract: Antimony doped tin oxide powder having an open pore structure wherein the pore volume is at least 0.005 cc/g for any mean pore diameter within the range of 0.1 to 8 micrometers is disclosed.

Abstract: The present invention relates to a novel cost efficient luminescent composition comprising particles of a core material which have been coated with a luminescent material that is distributed in the form of a chemically homogeneous layer. The average diameter of the core particle is in the range of from about 0.5 to 20 microns, and the coating corresponds to between about 2 and 30 wt % of the total composition. One aspect the invention relates to a process for preparing the composition which comprises decomposing chelated metal luminescent precursors in solution at a relatively high pH while in the presence of dispersed core particles, thereby coating the core particles with hydrous metal oxides, recovering the coated particles, washing the coated particles substantially free from soluble species, drying and calcining. In another aspect, a hydrous oxide coating is converted to a sulfide coating by treating the hydrous coating with a source of active sulfur.