Abstract: There is disclosed a process for cleaning a harmful gas which comprises bringing a gas containing a basic gas as a harmful component such as ammonia and amines into contact with a cleaning agent comprising a cupric salt supported on an inorganic carrier composed of an metallic oxide such as silica and alumina or a metallic oxide mixture of cupric oxide and manganese dioxide to remove the harmful component from the gas containing a basic gas.According to the above process, it is made possible to effectively remove a basic gas such as ammonia and trimethylamine contained in the exhaust gas from semiconductor production process; and a harmful basic gas contained in dilution gas such as air or nitrogen which dilutes the harmful gas suddenly leaked in emergency from a gas bomb filled inside with the harmful gas. Moreover, the process enables to prevent the occurrence of fire even in the coexistence of other gas such as silane, while maintaining excellent effect on the removal of the harmful gas.

Abstract: A process for cleaning a harmful gas which includes contacting a gas containing as a harmful component an alkoxide compound of the formula M(OR).sub.x, wherein M is a metallic element, OR is an alkoxy group and x is the valency of the metal, such as trimethylphosphorous, with a cleaning agent, which is an alkali metal compound such as potassium hydroxide, sodium hydroxide and potassium oxide, supported on a metallic oxide composition comprising cupric oxide and manganese dioxide, wherein the total amount of the cupric oxide and the manganese dioxide is at least 60% by weight based on the total amount of the metallic oxide, to remove the harmful component from the harmful gas. The process effectively and safely removes harmful components in gases exhausted from semiconductor manufacturing processes.

Abstract: An electrolytic oxygen sensor in which the atmosphere is admitted to one side of the solid electrolyte through an air-permeable spacer through a dual concentric tube structure. Holes are formed in the inner tube to complete the air flow to the atmosphere. The small size of the holes prevent the entry of water and oil contaminants.

Abstract: An oxygen sensor including an oxygen sensing element having one closed end and inner and outer electrode layers formed on the inner and outer surfaces thereof, an output withdrawing lead wire electrically connected to the inner electrode layer formed on the inner surface of the oxygen sensing element, and a metallic terminal disposed in connection between the output withdrawing lead wire and the inner electrode layer. The metallic terminal includes opposed resilient portions separated by a gap and disposed in contact with the inner periphery of the inner electrode layer to apply a radial force to the inner electrode layer, whereby not only the damage of the oxygen sensing element is prevented but also the mounting operation can be done easily without threaded insertion of the metallic terminal.

Abstract: A precombustion chamber provided with an arrangement for thermally insulating a cylinder head of an internal combustion engine from a combustion gas in the precombustion chamber comprising: (a) a hollow ceramic body which provides a precombustion chamber and is disposed within the hollow space for the precombustion chamber; (b) a hollow fitting member disposed surrounding the hollow ceramic body within the hollow space for mitigating and absorbing the stress produced between the cylinder head and the hollow ceramic body; and (c) seal means for sealing a space between the hollow ceramic body and the fitting member to provide a closed space therebetween, wherein said hollow fitting member is tightly secured to the hollow ceramic body through the seal means.

Abstract: A gas sensor including a gas sensor body in which is centrally inserted a gas detecting element and which permits the gas sensor itself to be attached to other members; a protective sleeve attached to an end portion of the gas sensor body; a seal member formed of a heat-resistant synthetic resin, the seal member being disposed inside an end portion on a lead wire draw-out side of the protective sleeve, with a lead wire extending through the seal member; and a spring member mounted within the protective sleeve for urging the seal member liquid-tightly against the lead wire draw-out side end portion of the protective sleeve. Since the seal member disposed in an end portion of the protective sleeve is formed of a heat-resistant synthetic resin, the durability thereof is improved even where high temperature gases such as the exhaust gases of internal combustion engines or the like are to be detected.

Abstract: A heater-incorporating oxygen sensor includes a solid electrolyte oxygen sensor element comprising a solid electrolyte provided with electrodes on both its sides and a heater, said heater being a ceramic heater formed by sintering and embedding a metallized pattern in a ceramic insulator as one solid body, said ceramic heater being disposed within a space surrounded with said oxygen sensor element.