Abstract: The power generation efficiency of a microbial power generator is increased by using an easy and inexpensive unit. Two plate-like cation-exchange membranes are disposed in parallel in a tank. This arrangement allows an anode chamber to be formed between the cation-exchange membranes. Two cathode chambers are separated from the anode chamber by using the respective ion-permeable nonconductive membranes. An oxygen-containing gas is made to pass through the cathode chamber. An anode solution is supplied to the anode chamber, and, preferably, the anode solution is made to circulate. A biologically treated exhaust gas is used as the oxygen-containing gas to be supplied to the cathode chamber. Carbon dioxide in the biologically treated exhaust gas can promote transport of Na+ and K+ ions, and water vapor can increase the ion permeability, thereby increasing the power generation efficiency.

Abstract: To increase the power generation efficiency of a microbial power generator by using an easy and inexpensive unit. Two plate-like cation-exchange membranes 31 are disposed in parallel in a tank 30. This arrangement allows an anode chamber 32 to be formed between the cation-exchange membranes 31. Two cathode chambers 33 are separated from the anode chamber 32 by using the respective ion-permeable nonconductive membranes 31. An oxygen-containing gas is made to pass through the cathode chamber 33. An anode solution L is supplied to the anode chamber, and, preferably, the anode solution is made to circulate. A biologically treated exhaust gas is used as the oxygen-containing gas to be supplied to the cathode chamber 33. Carbon dioxide in the biologically treated exhaust gas can promote transport of Na+ and K+ ions, and water vapor can increase the ion permeability, thereby increasing the power generation efficiency.

Abstract: The power generation efficiency of a microbial power generator is increased by using an easy and inexpensive unit. Two plate-like cation-exchange membranes are disposed in parallel in a tank. This arrangement allows an anode chamber to be formed between the cation-exchange membranes. Two cathode chambers are separated from the anode chamber by using the respective ion-permeable nonconductive membranes. An oxygen-containing gas is made to pass through the cathode chamber. An anode solution is supplied to the anode chamber, and, preferably, the anode solution is made to circulate. A biologically treated exhaust gas is used as the oxygen-containing gas to be supplied to the cathode chamber. Carbon dioxide in the biologically treated exhaust gas can promote transport of Na+ and K+ ions, and water vapor can increase the ion permeability, thereby increasing the power generation efficiency.

Abstract: To increase the power generation efficiency of a microbial power generator by using an easy and inexpensive unit. Two plate-like cation-exchange membranes 31 are disposed in parallel in a tank 30. This arrangement allows an anode chamber 32 to be formed between the cation-exchange membranes 31. Two cathode chambers 33 are separated from the anode chamber 32 by using the respective ion-permeable nonconductive membranes 31. An oxygen-containing gas is made to pass through the cathode chamber 33. An anode solution L is supplied to the anode chamber, and, preferably, the anode solution is made to circulate. A biologically treated exhaust gas is used as the oxygen-containing gas to be supplied to the cathode chamber 33. Carbon dioxide in the biologically treated exhaust gas can promote transport of Na+ and K+ ions, and water vapor can increase the ion permeability, thereby increasing the power generation efficiency.

Abstract: A scroll fluid machine is capable of readily providing a back-pressure chamber having an increased pressure-receiving area and yet capable of being reduced in size. A fixed scroll member is secured to a casing. An orbiting scroll member is provided at a position facing the fixed scroll member. A holder is provided at the back of the orbiting scroll member, and a coupling member is provided to face the orbiting scroll member across the holder. The coupling member couples together the orbiting scroll member and a driving shaft and performs an orbiting motion together with the orbiting scroll member. A back-pressure plate is provided at the back of the orbiting scroll member, and a back-pressure chamber is formed between the back-pressure plate and the holder.

Abstract: A scroll fluid machine is capable of readily providing a back-pressure chamber having an increased pressure-receiving area and yet capable of being reduced in size. A fixed scroll member is secured to a casing. An orbiting scroll member is provided at a position facing the fixed scroll member. A holder is provided at the back of the orbiting scroll member, and a coupling member is provided to face the orbiting scroll member across the holder. The coupling member couples together the orbiting scroll member and a driving shaft and performs an orbiting motion together with the orbiting scroll member. A back-pressure plate is provided at the back of the orbiting scroll member, and a back-pressure chamber is formed between the back-pressure plate and the holder.

Abstract: A lip ring is attached to a piston so as to be rotatable relative to the piston in a circumferential direction, and a seal portion is provided between a ring attachment groove of the piston and an attachment portion of the lip ring. During a suction stroke, the lip ring can be rotated in a circumferential direction of the piston, thus distributing wear around the entire periphery of a lip portion of the lip ring. During a compression stroke, leakage of air from a compression chamber can be prevented by means of the seal portion provided between the ring attachment groove and the lip ring.

Abstract: A lip ring is attached to a piston so as to be rotatable relative to the piston in a circumferential direction, and a seal portion is provided between a ring attachment groove of the piston and an attachment portion of the lip ring. During a suction stroke, the lip ring can be rotated in a circumferential direction of the piston, thus distributing wear around the entire periphery of a lip portion of the lip ring. During a compression stroke, leakage of air from a compression chamber can be prevented by means of the seal portion provided between the ring attachment groove and the lip ring.

Abstract: The active temperature of an exhaust gas cleaning catalyst is shifted to a higher temperature side when Al.sub.2 O.sub.3 and/or CeO.sub.2 is used as a co-catalyst and/or when an oxidation number of Pt or Ir which is used as the noble active component is plus four.

Abstract: A catalyst (3) for purifying an automotive exhaust gas, in which inner and outer catalytic layers (5,6), each of which has a base material and a catalytic material held by the base material, are stratified on a honeycomb-type carrier (4). In the catalyst (3), the inner catalytic layer (5) contains a palladium component as the catalytic component. Further the inner catalytic layer (5) contains a nickel oxide component for preventing poisoning of the palladium component. On the other hand, though the outer catalytic layer (6) contains a rhodium component as the catalytic component, it does not contain a palladium component nor a nickel oxide component.

Abstract: An engine exhaust gas purifying catalyst contains, as active substances, platinum and at least one of iridium, III-B metals and IV-B metals. In particular, the catalyst contains mainly platinum and iridium and, desirably, rhodium as an additive catalyst substance.

Abstract: The present invention provides a brake fluid pressure generator comprising a barometric pressure booster and a master cylinder interlocked to each other at an interlocking portion which has a stepped configuration. A return spring is attached to the stepped portion of the interlocking portion. A stopper is fixed to the large diameter part of the interlocking portion. The return spring has a diameter larger than the small diameter part of the interlocking portion. Because the interlocking portion comes inside the return spring when they come closer, the overall length of the master cylinder and the barometric pressure booster is made smaller. Configuration of the return spring remains simple and the number of members is maintained small.

Abstract: A catalytic convertor for treating exhaust gas includes a first catalyst layer formed on a base material and a second catalyst layer formed on the first catalyst layer. The first catalyst layer is composed of metal-containing silicate provided with transition metal by ion exchange and at least one precious metal borne on the silicate, and the second catalyst layer is composed of metal-containing silicate provided with transition metal by ion exchange and at least one metal borne on the silicate which is selected from the group consisting of Zr, Co, Cu, Cr, Mn, Y, Fe, Ni, V, Ti, Zn, Ga, Ba, Mg, La, Ce, Pr, Nd, Sm and Tb and differs from the transition metal provided on the silicate by ion exchange.

Abstract: An engine exhaust purification system is provided with a catalyst in an exhaust line, and oxygen sensors disposed in the exhaust line upstream and downstream from the catalyst, respectively. Deterioration of the catalyst is judged based on a frequency ratio of reversal of an output from the downstream oxygen sensor with respect to a threshold value to an output from the upstream oxygen sensor with respect to a threshold value. The threshold value of the deteriorated oxygen sensor is changed so as to vary the frequency ratio of reversal.

Abstract: An exhaust purification apparatus for an engine uses a catalytic converter provided in an exhaust system of the engine. First and second exhaust sensors are provided on upstream and downstream sides, respectively, of the catalyst converter in the exhaust system. Detected values from the first and second exhaust sensors are used for feed back control of air fuel ratio and judging deterioration of the catalyst of the catalytic converter, respectively. A control constant of the air fuel ratio of the feed back control is changed so that the second exhaust sensor detects in accordance with a condition of the catalyst.

Abstract: In an exhaust system for an internal combustion engine, including an upstream catalytic converter and a downstream catalytic converter, emission levels of exhaust gas are detected at positions upstream from the upstream catalytic converter, between the upstream and downstream catalytic converters, and downstream from the downstream catalytic converter, respectively. An air-fuel ratio is feedback controlled based on an emission level detected by the first emission sensor or feedback controlled based on an emission level detected by the second emission sensor when the engine operates in a specific vehicle operating condition. Deterioration of the downstream catalytic converter is detected based on an emission level detected by the third emission sensor while an air-fuel ratio is feedback controlled based on the emission level detected by the second emission sensor.

Abstract: An exhaust system for an automobile engine having two groups of cylinders has a catalytic device. Deterioration of the catalytic device is detected based on an oxygen level in exhaust gas passed through the catalytic device. A feedback control of an air-fuel ratio is conducted for the cylinder groups all together, based on either of the air-fuel ratios determined, based on emission levels of exhaust gas discharged, for one of two of the groups of cylinders, only when a specific vehicle driving condition is detected.

Abstract: An exhaust gas sensor containing BaSnO.sub.3 or the like and a process for producing the sensor. The BaSnO.sub.3 is made free of segregation and adapted to have acid-base strength of at least 6.8 as determined with Hammett's indicator. Causes to reduce the acid-base strength of the BaSnO.sub.3 includes presence of Si and B, and causes to increase the acid-base strength include addition of Mg or Ca. The desired BaSnO.sub.3 can be prepared by precipitating BaSnO.sub.3 hydrous crystals while preventing introduction of Si and B thereinto especially with use of a container lined with a synthetic resin to prevent introduction of Si and B from the container, adding Mg or Ca to the precipitate, and thermally decomposing the precipitate.

Abstract: A method of producing an exhaust gas sensor incorporating BaSnO.sub.3. Stannate ion and barium ion are reacted in a strong alkali to precipitate water-containing crystals of BaSnO.sub.3 such as BaSnO.sub.3.3H.sub.2 O, BaSnO.sub.3.5H.sub.2 O or the like. When thermally decomposed, the precipitate gives BaSnO.sub.3 free from segregated Ba and Sn elements. The product was then molded and thereafter sintered to obtain the sensor.

Abstract: An exhaust gas sensor in which a metal oxide semiconductor containing at least one member of a group of elements consisting of Sn, Fe, Ni and Co and Pt electrodes having ZrO.sub.2, deposited in the grain boundary are used. Such metal oxide semiconductors include, for example, SnO.sub.2, BaSnO.sub.2, BaSnO.sub.3, SrSnO.sub.3, and CaSnO.sub.3. The exhaust gas sensors are manufactured by mixing such compounds as BaCO.sub.3, SrCO.sub.3 or CaCO.sub.3 with SnO.sub.2 in equimolar ratio to react them in air at 1200.degree. C. for four hours. The compounds thus obtained were pulverized and Pt electrodes with ZrO.sub.2 were imbedded therein, then were molded into sensor chips. The chips thus molded were baked by heating in air. After the chip has been sintered the exhaust gas sensor was assembled. It comprised an insulating substrate of alumina, etc. having a recess provided at one end thereof in which the aforementioned sensor chip was housed.