Abstract: A composite catalyst having a substrate, and a catalytic layer supported on the substrate and including 100 parts by weight of particles of a photocatalyst dispersed in 6-32 parts by weight of a matrix of an alkali metal silicate.

Abstract: Nitrogen oxides are removed from an exhaust gas containing nitrogen oxides and oxygen in an amount larger than its stoichiometric amount relative to unburned components in the exhaust gas, by (i) disposing an exhaust gas cleaner in a flow path of the exhaust gas, the exhaust gas cleaner comprising 0.2-15 weight % (on a metal basis) of fine silver or silver oxides having an average diameter of 10-1,000 nm and supported on a porous inorganic oxide; (ii) introducing hydrocarbons and/or oxygen-containing organic compounds into the exhaust gas on the upstream side of the exhaust gas cleaner; and (iii) bringing the exhaust gas into contact with the exhaust gas cleaner at a temperature of 200.degree.-600.degree. C., thereby causing a reaction of nitrogen oxides with the hydrocarbons and/or oxygen-containing organic compounds.

Abstract: A three-dimensional network structure comprising three-dimensionally interconnected spherical silica particles, having specific physical characteristics including diameter, pores on the surfaces of the particles, cross-sectional areas of the bonds interconnecting the spherical silica particles, elasticity modulus, voids content, and silica content, the surfaces of the spherical silica particles being wholly or partly covered with a water-soluble polymer, the network structure being able to remain substantially intact when heat-treated and being able to undergo machining. There is also provided a method of making a three-dimensional network structure comprising spherical silica particles, comprising hydrolyzing and polymerizing a low polymer of an alkoxysilane in a mixed solution containing the alkoxysilane low polymer and a water-soluble polymer in a mixed solvent composed of water and an alcohol in the presence of an acid catalyst.

Abstract: Hydrogen is produced from a cellulose-containing biomass by heating the biomass in the presence of water and a catalyst at a temperature of 250.degree.-374.degree. C. and at a pressure higher than the saturated vapor pressure of water. The catalyst includes a catalytic metal selected from the group consisting of nickel, iron, cobalt, molybdenum, tungsten, platinum and mixtures thereof.

Abstract: Hydrogen is produced from a hydrocarbon by contacting the hydrocarbon with fine particles of a carbonaceous material having an external surface area of at least 1 m.sup.2 /g at a temperature sufficient to pyrolyze the hydrocarbon.

Abstract: A unique method is proposed for fine patterning of a polymeric resin film on a substrate surface or fine patterning of the substrate surface with the patterned resin film as the resist. The method comprises the steps of: (a) forming a thin film of the resin on the substrate surface; (b) pressing the resin film pattern-wise under a pressure in a specified range by using, for example, a fine needle tip so as to enhance adhesion of the resin molecules to the substrate surface; and (c) dissolving away the resin film with an organic solvent selectively in the areas where the pressure is not applied in step (c) leaving the resin in a pattern-wise area after application of the pressure. The fineness of this patterning can be extremely high to be in the molecular size order.

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: There is disclosed a variant-type carbohydrate hydrolase that has been increased transglycosylation activity by substituting another amino acid residue for the tyrosine residue that is present in the active center of the hydrolase, which hydrolase is an amylase or an enzyme analogous to amylase; a gene or a DNA sequence of the carbohydrate hydrolase with mutation introduced into the base sequence that encodes the tyrosine residue; and a vector or a transformant which comprises the DNA sequence. There is also disclosed a method for producing a variety of oligosaccharides and the like by using the variant-type carbohydrate hydrolase.

Abstract: There is disclosed a variant-type carbohydrate hydrolase that has been increased transglycosylation activity by substituting another amino acid residue for the tyrosine residue that is present in the active center of the hydrolase, which hydrolase is an amylase or an enzyme analogous to amylase; a gene or a DNA sequence of the carbohydrate hydrolase with mutation introduced into the base sequence that encodes the tyrosine residue; and a vector or a transformant which comprises the DNA sequence. There is also disclosed a method for producing a variety of oligosaccharides and the like by using the variant-type carbohydrate hydrolase.

Abstract: Proposed is an efficient method for the preparation of vitreous hollow microspheres from particles of a vitreous volcanic deposit by a heat treatment to effect expansion of the particles by foaming. The inventive method comprises a step, prior to the heat treatment for expansion of the particles, in which the starting particles are dispersed in an aqueous medium containing aluminum sulfate and urea each in a specified concentration followed by a heating treatment of the dispersion so as to deposit a coating layer of aluminum hydroxide on the particle surface so that the efficiency of foaming can be greatly improved without the disadvantage of particle agglomeration.

Abstract: There is disclosed a method for producing polycarbosilanes, comprising polymerizing silane of the formula SiH.sub.4 with dienes in the presence of a rare earth metal complex. Polycarbosilanes useful as photoreactive materials and as raw material of silicon carbide-series ceramics can be obtained in a high yield from silane (SiH.sub.4) and dienes.

Abstract: A novel synthetic mixed-layer silicate consisting of the layers of serpentine and layers of saponite each having a specified chemical composition is proposed, which has excellent dispersibility in water to form a colloidal dispersion capable of being converted into a gel by standing to be useful as a gelating agent exhibiting thixotropy along with unique porosity characteristics which enable the use thereof as an adsorbent.

Abstract: There is disclosed a crystalline aluminum organophosphate stable against heating, composed of a skeleton structure having micropores therein and represented by the following formula (I) in chemical composition:formula (I)[(Al.sub.2 O.sub.3).multidot.(RPO.sub.2).sub.x ]wherein R represents an alkyl group, and x is such a number that 2.0.ltoreq.x.ltoreq.3.6. The crystalline aluminum organophosphate is a microporous material having an inner wall of pores that is hydrophobic and has a flexibility, and it may be used as a separative adsorbent, a catalyst, a packing material for chromatography, and the like.

Abstract: Disclosed is a method for the preparation of a .beta.-thiolactam compound, i.e. a 7-substituted-2-oxa-7-azabicyclo [3.2.0]-heptan-6-thione, represented by the general formula ##STR1## in which R is an alkyl or aryl group, having usefulness as an intermediate for the synthesis of various biologically active compounds. The compound can be prepared by the reaction of an isothiocyanate compound R--NCS, R being the same as above, and 2,3-dihydrofuran, preferably, under pressurization up to 2000 atmospheres or higher at an elevated temperature.

Abstract: There is disclosed an ester compound that is resistant to decomposition in blood, but is quickly hydrolyzed in cancer cells, and functions as an anticancer agent. The ester compound has a structure represented by formula (I) or formula (II): ##STR1## wherein R.sub.1 represents a methyl group, a methoxy group, or a trifluoroacetamido group; R.sub.2 represents a phenyl group or a phenylmethyl group; and the absolute configuration of the asymmetric center marked with an asterisk is R.

Abstract: There is disclosed a method for surface-modifying a fluorocarbonpolymer-molded article and a method for chemical plating the surface. The method for surface-modifying comprises irradiating the fluorocarbonpolymer-molded article with an ultraviolet laser beam having a wavelength of 250 nm or less, in the presence of hydrazine compound, to make a surface of the said fluorocarbonpolymer-molded article hydrophilic. The surface made being hydrophilic is made lipophilic by chemical treating with an organic acid anhydride. The method for chemical plating comprises chemical plating the surface made being hydrophilic by the above method for surface-modifying, to deposit a metal film on a surface of the fluorocarbonpolymer-molded article.

Abstract: A method of solubilizing iodine in an aqueous medium is disclosed, which includes mixing the aqueous medium with iodine together with a polystyrene derivative having the recurring units of the formula ##STR1## wherein R represents an alkylene group having 1-4 carbon atoms and n is an integer of 2-20. An antiseptic composition includes an aqueous medium, the above polystryene derivative, and iodine dissolved in the aqueous medium.

Abstract: A robot hand for gripping workpieces to be forged which are subjected to impact loads is provided. The robot hand 2 includes a grip 3 for gripping a workpiece to be forged and a grip support 2a for supporting the grip 3. A grip guide 12 for supporting the grip 3 so that it is movable in a plane perpendicular to the longitudinal axis of the grip support and slidable in forward and rearward directions and a spherical seat 5 for bearing the grip guide 12 so that it can be inclined are provided within a casing 4 of the grip support 2a. The casing 3 of the grip support 2a is provided with various actuators 9, 10, 11, 7 for changing the supporting state between a state in which the grip 3 can be moved and inclined and a state in which the grip 3 can not be moved and inclined. The grip 3 is brought into the movable and inclinable state for absorbing an impact when the impact load is applied to the gripped workpiece to be forged.

Abstract: There is disclosed a method for producing aromatic polyamides represented by the following formula (III), which comprises reacting an aromatic dihalogen compound represented by the following formula (I) with a diamine compound represented by the following formula (II) in the presence of cobalt/phosphine complex and a basic substance under carbon monoxide atmosphere:X.sub.1 --Ar--X.sub.2 formula (I)wherein Ar represents an aromatic residue and X.sub.1 and X.sub.2 each represent a bromine or iodine atom,H.sub.2 N--R--NH.sub.2 formula (II)wherein R represents a divalent hydrocarbon group, andformula (III) ##STR1## wherein Ar and R each have the same meaning as the above, and n is a positive integer.

Abstract: Proposed is a dielectric thin film of a substituted lead titanate having a chemical composition expressed by the formulaPb(Ti.sub.1-x M.sub.x)O.sub.3in which the subscript x is a positive number in the range from 0.05 to 0.50 and M is an element selected from the group consisting of niobium, tantalum, vanadium, antimony, bismuth, arsenic, tungsten, hafnium, germanium, tin, aluminum and gallium substituting for a part of the titanium atoms in the perovskite crystal lattice of lead titanate. Different from thin films of unsubstituted lead titanate or conventional substituted lead titanates, the above defined dielectric thin films of the invention are free from the disadvantage that the dielectric constant of the thin film is greatly decreased when the thickness of the thin film is so small as to be 1 .mu.m or smaller so that the dielectric constant of the inventive dielectric thin film having a thickness of 0.5 .mu.