Abstract: A wave absorber is provided which has a wave absorption characteristic of 20 dB in a frequency band of 1 GHz to 20 GHz, is nonflammable, compact and lightweight, and has excellent durability. A porous ferrite is produced as the base material for which is an Ni--Zn type ferrite which has an excellent wave absorption characteristic in the high frequency range, and this serves as a wave absorber formed in the shape of a pyramid or triangular prism.

Abstract: An exhaust gas cleaner consisting essentially of a first catalyst consisting essentially of a first porous inorganic oxide supporting 1.6-8.7 weight percent of an Ag component, on a metal basis, and a second catalyst consisting essentially of a second porous inorganic oxide supporting 0.1-3.8 weight percent of a Pt component and 1-9.9 weight percent of a W component, each weight percent on a metal basis. The Ag component includes Ag or a compound thereof. The Pt component includes Pt, Pd, Ru, Rh, Ir, and Au. The W component includes W, V, Mn, Mo, Nb, and Ta.

Abstract: An exhaust gas cleaner is constituted of an Ag catalyst carrying an Ag component and a base metal catalyst carrying a Cu component and optionally W, V, Mo components, and a noble metal catalyst carrying a noble metal component. The base metal catalyst and the noble metal catalyst may be physically mixed to form a mixed catalyst. Another exhaust gas cleaner is constituted of the first Ag catalyst carrying an Ag component, the second Ag catalyst carrying an Ag component, a base metal catalyst carrying a Cu component and optionally W, V, Mo components, and a noble metal catalyst carrying a noble metal component. The second Ag catalyst carries the Ag component in an amount larger than that of the first Ag catalyst. The noble metal catalyst is physically mixed with the base metal catalyst to form a mixed catalyst. The exhaust gas cleaner can effectively remove nitrogen oxides in a wide temperature range of exhaust gas.

Abstract: A sliding member, in which the surface of a substrate is coated with a compound containing at least chromium nitride, wherein a columnar crystal structure is present in a tension fracture surface of the coating, the columns being aligned toward the coating surface from the substrate surface. The coating is formed on the substrate by contacting the substrate with a gas phase mixture containing chromium and nitrogen in a PVD process. In a preferred embodiment the PVD process is an ion plating process. The coating has superior resistance to peeling, abrasion and baking. The sliding member can be used as an engine part or a compressor part.

Abstract: A sliding member used as a sealing ring for a rotary shaft made of a lightweight aluminum alloy in an automatic transmission instead of a conventional cast iron sealing ring in order to prevent leakage of oil and reduce abrasion of the shaft consists of a PEEK resin composition which includes, as binder, 15.about.20 percent by weight of amorphous alumina powder having an average particle diameter of 5.mu. or less, 3.about.8 percent by weight of graphite powder having an average particle diameter of 5.mu. or less and 6.about.9 percent by weight of carbon powder having an average particle diameter of 30.mu. or less.

Abstract: Chill plates are integrated into a cassette to save the time which has been required to rearrange chill plates scattered at the time of output of castings. Each chill plate 1 is formed, on four corners thereof, with cavities 4 and 7 each corresponding to a quarter of a member to be chilled and with a center hole 9 through which a fixed shaft 7 is inserted in the center thereof.

Abstract: An exhaust gas cleaner being constituted by a first catalyst of a first porous inorganic oxide supporting a silver component in combination with a W component and a second catalyst of a second porous inorganic oxide supporting a Pt component and optionally a W component. The Ag component may include Ag and compounds thereof, the Pt component may include Pt, Pd, Ru, Rh, Ir, and Au, and the W component may include W, V, Mn, Mo, Nb, and Ta. The W component effectively catalyzes the reduction of nitrogen oxides by ammonia to enhance the removal efficiency of the exhaust gas cleaner.

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 piston seal device has a combined oil scraping ring that includes a steel annular oil scraping ring body having an M-, I- or H-shaped cross section, and an annular coil spring. The ring body has a cross-sectional cut at one location and includes an upper rail member, a lower rail member and a strut holding the upper and lower rail members and having an annular groove in its outer circumferential side, the annular groove having a number of circumferentially spaced oil holes. The annular coil spring is fitted into the annular groove in a stretched state for urging the strut diametrically inward toward the piston rod, whereby the inner circumferential surfaces of the upper and lower rail members are brought into pressured contact with the outer peripheral surface of the piston rod owing to the constraining force of the spring. The oil scraping ring contacts the outer peripheral surface of the piston rod while flexing to follow up the shape of the surface, thereby improving the oil sealing effect.

Abstract: The invention particularly relates to a solenoid valve used in a control fluid, and one end of a center pole on the side opposite from a plunger is covered with theend face of a housing, and a communication passage is formed in the housing to communicate a through hole of the center pole with an opening formed on the housing on the side of the plunger. The communication passage has an end face groove and at least one side face groove on the end face and the side face of the housing. A volume of the side face groove is larger than a variation in volume of a space between the plunger and the center pole due to the movement of the plunger, and it is 2.5 times or more of the variation in volume of the space between the plunger and the center pole due to the movement of the plunger.

Abstract: The sand-metal ratio of a mold used for casting a crank shaft or cam shaft having discrete shapes is reduced to make the mold more compact. Basic discrete cavities (15) including cavities (6) corresponding to one half of shaft portions and cavities (7) corresponding to one half of cam portions are staggered by axially offsetting them in horizontal and/or vertical direction.

Abstract: An exhaust gas cleaner is constituted of an Ag catalyst carrying an Ag component and a base metal catalyst carrying a Cu component and optionally W, V, Mo components, and a noble metal catalyst carrying a noble metal component. The base metal catalyst and the noble metal catalyst may be physically mixed to form a mixed catalyst. Another exhaust gas cleaner is constituted of the first Ag catalyst carrying an Ag component, the second Ag catalyst carrying an Ag component, a base metal catalyst carrying a Cu component and optionally W, V, Mo components, and a noble metal catalyst carrying a noble metal component. The second Ag catalyst carries the Ag component in an amount larger than that of the first Ag catalyst. The noble metal catalyst is physically mixed with the base metal catalyst to form a mixed catalyst. The exhaust gas cleaner can effectively remove nitrogen oxides in a wide temperature range of exhaust gas.

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 sliding material for light metal material contains polyether-ether ketone and/or polyether-nitride. Further, 20.about.35% of sericite is added in the sliding material as a solid lubricant to improve self-wear resistance of the sliding material and wear resistance of a mating part with respect to the sliding material.

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 using an exhaust gas cleaner having Ag supported by a porous inorganic oxide body and second catalyst containing second catalytically active components supported by a porous inorganic oxide body. The second catalytically active components consist essentially of Cu and/or other metals such as alkali metal elements, rare earth elements, etc.

Abstract: A method of cleaning an exhaust gas using an exhaust gas cleaner constituted by a first catalyst comprising a first porous inorganic oxide supporting an Ag component, a W component and a Pt component and optionally a second catalyst comprising a second porous inorganic oxide supporting a Pt component alone or in combination with a W component. The Ag component may include Ag and compounds thereof, the Pt component of the first and second catalysts may include Pt, Pd, Ru, Rh, Ir and Au, and the W component of the first and second catalysts may include W, V, Mn, Mo, Nb and Ta. The W component effectively catalyze the reduction of nitrogen oxides by ammonia to enhance the removal efficiency of the exhaust gas cleaner.

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 using an exhaust gas cleaner having Ag supported by a porous inorganic oxide body and second catalyst containing second catalytically active components supported by a porous inorganic oxide body. The second catalytically active components consist essentially of Cu and/or other metals such as alkali metal elements, rare earth elements, etc.

Abstract: A sliding member, in which the surface of a substrate is coated with a compound containing at least chromium nitride, wherein a columnar crystal structure is present in a tension fracture surface of the coating, the columns being aligned toward the coating surface from the substrate surface. The coating is formed on the substrate by contacting the substrate with a gas phase mixture containing chromium and nitrogen in a PVD process. In a preferred embodiment the PVD process is an ion plating process. The coating has superior resistance to peeling, abrasion and baking. The sliding member can be used as an engine part or a compressor part.

Abstract: An exhaust gas cleaner is constituted by a first catalyst carrying an Ag component, a second catalyst carrying an Ni component or two or more of an Ni component, Ag component and Cu component, and optionally a third catalyst carrying a noble metal component alone or in combination with a base metal component. The second and third catalysts may be physically mixed to form a mixed catalyst. Another exhaust gas cleaner is constituted by a mixed catalyst of a first catalyst carrying an Ag component and a second catalyst carrying an Ni component alone or in combination with a Cu component, and a third catalyst carrying a noble metal component alone or in combination with a base metal component. Still another exhaust gas cleaner is constituted by a first catalyst carrying an Ag component, a second catalyst which is a mixture of an Ni catalyst, Ag catalyst and Cu catalyst, and optionally a third catalyst carrying a noble metal component alone or in combination with a base metal component.

Abstract: An exhaust gas cleaner is constituted by a first Ag catalyst, a second Ag catalyst, a transition metal catalyst selected from the group consisting of a Pt catalyst, a W catalyst, a W+Pt catalyst and a mixed catalyst of the Pt catalyst and the W catalyst. The second Ag catalyst and the Pt catalyst may be physically mixed together to form a mixed catalyst. Another exhaust gas cleaner is constituted by an Ag catalyst, a Cu catalyst and a W+Pt catalyst. The Cu catalyst and the W+Pt catalyst may be physically mixed together to form a mixed catalyst. Still another exhaust gas cleaner is constituted by a mixed catalyst of an Ag catalyst and a Cu catalyst. The exhaust gas cleaner can effectively remove nitrogen oxides in a wide temperature range of exhaust gas.