Abstract: A catalyst for steam reforming of hydrocarbons comprises porous aluminum oxide and nickel oxide, characterized in that the porous aluminum oxide in which the pore volume given by the pores of the pore diameter ranging from 60 to 120 A is not less than 0.35 ml./g. and the pore volume given by the pores of the pore diameter of more than 120 A is not less than 0.1 ml./g. and the purity determined upon ignition dryness is not less than 98% by weight is impregnated with nickel in an amount ranging from 10 to 30% by weight, as converted to nickel oxide basis, based on the total amount by weight of the catalyst.

Abstract: A mechanochemical method of polishing a gadolinium gallium garnet single crystal characterized by the use of a composition made of a polishing agent selected from the group consisting of aluminum oxide, cerium oxide, zirconium oxide and chromium oxide suspended in an alkaline silicate solution selected from a group consisting of sodium silicate solution and potassium silicate solution.

Abstract: A composition for polishing synthetic resin comprises a calcined alumina polishing agent and water. The polishing agent is prepared by burning boehmite, crushing it into particles and separating particles having a predetermined particle distribution. Also disclosed is a synthetic resin polishing composition further containing as a polishing accelerator an aluminum compound selected from among aluminum nitrate, polyaluminum chloride, aluminum bromide, aluminum sulfate, aluminum iodide, aluminum chloride and aluminum phosphate and mixtures thereof.

Abstract: A catalyst comprising 10 to 30 wt.% of nickel as nickel oxide, 20 to 60 wt.% of calcium as calcium oxide, 10 to 70 wt.% of aluminum as aluminum oxide and containing less than 1 wt.% of silicon dioxide. The catalyst is prepared by using: as the starting material for the nickel component, fine particles of nickel oxide obtained by heating a nickel compound which is decomposed to nickel oxide by heating at a temperature in the range of 400.degree. to 800.degree. C in the presence of oxygen; as the starting material for the calcium component, calcium oxide per se or a calcium compound which is decomposed to calcium oxide by heating and; as the starting material for the aluminum component, alumina cement of a high purity. The catalyst is prepared by mixing and kneading the starting materials with water, molding the same, then keeping the catalyst composition under a highly humid atmosphere at a temperature in the range of 5.degree. to 35.degree.

Abstract: A sintered catalyst article is prepared by:molding into a shaped article and aging (I) eitherA. a refractory powder of calcium aluminate substantially free of silicon dioxide, alone, orB. a homogenous mixture of1. said refractory powder and2. at least one member selected from the group consisting of aluminum oxide, calcium oxide, beryllium oxide, magnesium oxide, strontium oxide and a compound which is converted by heating to one of said oxides;(II) sintering said molded and aged article at a temperature above 1150.degree.C;the thus sintered catalyst article containing 10 to 60 wt. percent of calcium oxide, 30 to 90 wt. percent of aluminum oxide, 0 to 30 wt. percent of at least one oxide selected from the group consisting of beryllium oxide, magnesium oxide and strontium oxide, and less than 0.2 wt. percent of silicon dioxide.