Abstract: The invention provides a lithium manganese oxide spinel suited as a cathode active material for lithium ion secondary batteries showing excellent high-temperature cycling behavior. The lithium manganese oxide is represented by the following general formula (1): Li1+&agr;Mn2−&agr;−yMyO4−&dgr; wherein O≦&agr;≦0.5, 0.005≦y≦0.5, −0.1≦&dgr;÷0.1, and M represents a metal element other than Li and Mn, and which shows the ratio of a main peak intensity at 5±40 ppm to a main peak intensity at 525+40 ppm (I0ppm/I500ppm), each intensity being obtained by 7Li-NMR measurement according to the following measuring method, falling within the following range: I0ppm/I500ppm≦0.65y+0.02.

Abstract: The invention provides a lithium manganese oxide spinel suited as a cathode active material for lithium ion secondary batteries showing excellent high-temperature cycling behavior.

Abstract: A process for producing a precursor of a phosphorus-vanadium oxide catalyst for production of maleic anhydride by vapor phase oxidation of a hydrocarbon having 4 carbon atoms, which comprises reacting phosphoric acid and a pentavalent vanadium compound in an organic solvent capable of reducing at least a portion of the pentavalent vanadium to a valence state of +4, the phosphoric acid being substantially composed of orthophosphoric acid, and a phosphoric acid solution whose concentration is 88 to 96% being used as a source of the phosphoric acid; and a process for producing the catalyst comprising dry-pulverizing the catalyst precursor.

Abstract: An oxide catalyst for producing maleic anhydride by vapor phase oxidation of a hydrocarbon having 4 carbon atoms, obtainable by (1) reacting a pentavalent vanadium compound and a pentavalent phosphorus compound in an organic solvent in the presence of a reducing agent capable of reducing the pentavalent vanadium to the tetravalent state to produce the crystalline composite oxide particles containing tetravalent vanadium and pentavalent phosphorus, (2) dry-pulverizing the obtained crystalline composite oxide particles in a high-speed gas flow, (3) mixing the pulverized particles with an aqueous solution containing tetravalent vanadium and pentavalent phosphorus to form a slurry, and (4) spray-drying the slurry and then calcining.

Abstract: Porous glass consisting essentially of silica, zirconia and an alkali metal compound, wherein the content of zirconia is at least 5% by weight and the content of the alkali metal compound is at least 2% by weight as calculated as M.sub.2 O wherein M is an alkali metal element, and the total pore volume (A) of pores having pore radii of from 20 to 10,000 .ANG. is at least 0.2 ml/g, and the proportion of the pore volume (B) of pores having pore radii of from 100 to 10,000 .ANG. to the total pore volume (A) of pores having pore radii of from 210 to 10,000 .ANG. is at least 80%.

Abstract: Porous glass consisting essentially of silica, zicronia and an alkali metal compound, wherein the content of zirconia is at least 5% by weight and the content of the alkali metal compound is at least 2% by weight as calculated as M.sub.2 O wherein M is an alkali metal element, and the total pore volume (A) of pores having pore radii of from 20 to 10,000 .ANG. is at least 0.2 ml/g. and the proportion of the pore volume (B) of pores having pore radii of from 100 to 10,000 .ANG. to the total pore volume (A) of pores having pore radii of from 20 to 10,000 .ANG. is at least 80%.