Abstract: An anode catalyst contains gold fine particles, and/or at least one member selected from the group consisting of titanium, vanadium, gallium, zirconium, niobium, cerium, tantalum, indium, and the oxides of these metals, and/or at least one member selected from the group consisting of platinum, ruthenium, and ruthenium oxides are coated on a conductive support.

Abstract: Apparatus 1 for evaluating catalyst performance according to the invention comprises a reaction vessel 2 in which a plurality of catalysts S are disposed at a distance, supply pipes 3 for supplying a reactant gas into the reaction vessel 2, a plurality of measuring instruments 7 provided with gas sensors 71 for sensing the gas formed by the contact of the reactant gas with a plurality of catalysts S, and outputting signals according to the kinds and concentrations of the formed gas, and a calculating unit 8 for receiving the output signals from the plurality of measuring instruments 7 and identifying the kinds of the formed gas and calculating the concentrations thereof. With such a constitution, performance evaluation on a plurality of catalysts can be made concurrently, quick and in simple steps.

Abstract: A catalyst for producing acrolein by oxidizing ethane contains silicon, iron, an alkali metal, and oxygen. A method for producing acrolein includes the step of oxidizing ethane in the presence of the catalyst and a method for producing the catalyst includes the steps of mixing porous silicon oxide with an iron compound and an alkali metal compound and calcining the resultant mixture.

Abstract: There are disclosed a nitrogen oxide removal catalyst comprising palladium fixed on at least one metal oxide selected from the group consisting of titanium oxide, aluminum oxide, zinc oxide, and magnesium oxide, and a method for removing nitrogen oxides, comprising bringing a nitrogen oxide-containing gas into contact with the above-mentioned catalyst in the presence of hydrogen.

Abstract: A third-order nonlinear optical material having a metal oxide contained in a transparent polymer.

Abstract: A humidity detection material includes oxide of at least one metal selected from the group consisting of Mg, Ca, Mn, Fe, Co, Ni, and Cu. The metal oxide is preferably in the form of a porous material. The metal oxide is formed preferably in the form of a thin film on a transparent substrate. The humidity detection material is contacted with water vapor in the presence of a gas such as air, and the optical absorbance of the humidity detection material is measured to detect the humidity. The humidity can be detected by an optical method.

Abstract: A material having ultrafine gold particles immobilized thereon consists essentially of at least one support selected from the group consisting of metal oxides, metal sulfides, and carbonaceous substances and ultrafine gold particles having a maximum particle diameter of 250 angstroms and deposited on the support with strong interaction. The material exhibits high activity as a catalyst for the oxidation of carbon monoxide to carbon dioxide. It is produced by causing a vaporized organic gold complex to contact at least one support selected from the group consisting of metal oxides, metal sulfides, and carbonaceous substances in an atmosphere of reduced pressure thereby inducing adsorption of the vapor of organic gold complex on the support and then heating the product of the adsorption to a temperature in the range of 100.degree.-700.degree. C.

Abstract: A carbon monoxide sensor in the form of a composite material including a transparent substrate, and a metal oxide layer provided over a surface of the substrate and containing nickel oxide and cobalt oxide in an amount providing an atomic ratio Ni/Co of 99:1 to 1:2. Carbon monoxide contained in an oxygen-containing gas is detected by a change in transmittace of light with a wave length of 350-1,500 nm passing through the composite material maintained at a temperature of 200.degree.-350.degree. C.

Abstract: A catalyst for the hydrogenation of CO and CO.sub.2 consists essentially of a metal oxide and gold. Synthesis of methanol and hydrocarbons by hydrogenation of CO and CO.sub.2 comprises establishing contact between a gaseous mass consisting of CO, CO.sub.2, and hydrogen and a catalyst consisting essentially of a metal oxide and gold.

Abstract: An ultra-fine gold particle-immobilized oxide is produced by a method which comprises adding an alkali compound to an aqueous solution containing a gold compound and a water-soluble metal salt thereby giving rise to a coprecipitate in the aqueous solution, separating the coprecipitate from the aqueous solution, and calcining the separated coprecipitate. This method is characterized by allowing the presence of a carboxylic acid or a carboxylate in the aqueous solution from the beginning or after the occurrence of the coprecipitate.

Abstract: An ultra-fine gold particle-immobilized alkaline earth metal compound having ultra-fine gold particles immobilized on an alkaline earth metal compound is useful as a catalyst or as an inflammable gas sensor. This compound is produced by (1) adding an aqueous solution of a gold compound dropwise to an aqueous solution containing an alkaline earth metal compound and having a pH value kept in the range of 7 to 11 thereby inducing immobilization of gold hydroxide on the compound, separating from the solution the gold hydroxide-immobilized compound, and calcining the separated compound at a temperature in the range of 80.degree. to 800.degree. C.

Abstract: A composite having ultra-fine gold particles uniformly and strongly immobilized in a deposited state on a metal oxide is obtained by preparing a solution containing the metal oxide as a carrier and a gold compound, adjusting the pH value of the solution to a specific level thereby inducing precipitation and deposition of gold hydroxide or gold on the carrier and, when the precipitate is in the form of gold hydroxide, further, firing the precipitate. The ultra-fine gold particles immobilized on metal oxides are useful as a catalyst for reduction and oxidation, in sensor elements for flammable gases, and as an electrode catalyst.

Abstract: A catalyst composite having gold or a mixture of gold with a catalytic metal oxide deposited on a carrier is produced by immersing a carrier in an aqueous solution containing a water-soluble salt of gold or water-soluble salts respectively of gold and other catalytic metal and urea and/or acetamide thereby allowing a precipitate to be deposited on the carrier and then firing the carrier holding the deposited precipitate thereon.