Abstract: In a method and apparatus for removing nitrogen oxides from the exhaust gas of a lean-burn automobile, a CO adsorbent component, which may, for example be made of Pd, Ru or Ir, is contained in an exhaust gas cleaning catalyst which captures NOx when the air-fuel ratio of exhaust gas is higher than theoretical air-fuel ratio, and reduces the captured NOx when the air-fuel ratio of exhaust gad is less than or equal to the theoretical air-fuel ratio. The catalyst, which includes Rh, Pt, and element selected from among the alkaline and alkaline earth metals (Na, Mg, K, Li, Cs, Sr and Ca), and a CO adsorbent material comprising Pd, Ir or Ru, has a CO desorption capacity that reaches at maximum level at a temperature within the range from 200 to 220° C. when its temperature is increased in a He gas flow at the rate of 5 to 10° C./min, after said catalyst is saturated at 100° C.

Abstract: Nitrogen oxides contained in an exhaust gas emitted from a lean-burn engine-mounted internal combustion engines are eliminated with a high efficiency. In an exhaust gas purification apparatus and process for eliminating nitrogen oxides contained in a combustion exhaust gas emitted from an internal combustion engine with a reducing gas such as carbon monoxide, hydrocarbons, etc. contained in the exhaust gas in the presence of a catalyst, a catalyst comprising all of Rh, Pt and Pd, at least one member selected from alkali metals and alkaline earth metals, and Mn or its compound, supported on a porous carrier is used.

Abstract: Nitrogen oxides contained in an exhaust gas emitted from a lean-burn engine-mounted internal combustion engines are eliminated with a high efficiency.

Abstract: In an exhaust gas purification process for eliminating nitrogen oxides contained in a combustion exhaust gas emitted from an internal combustion engine with a reducing gas such as carbon monoxide, hydrocarbons, etc. contained in the exhaust gas in the presence of a catalyst, a catalyst comprising all of Rh, Pt and Pd, at least one member selected from alkali metals and alkaline earth metals, and Mn or its compound, supported on a porous carrier is used.

Abstract: A ceramic multilayer circuit board comprising ceramic layers and wiring conductor layers laminated alternately, in which the ceramic layer has a thermal expansion coefficient lower than that of the wiring conductor and not lower than one half of that of the conductor layer and is formed from a glass which softens at a temperature not higher than the melting point of the wiring conductor layer; a semiconductor module having a high reliability in its solder joint part comprising said ceramic multilayer circuit board mounted with a ceramic carrier substrate being mounted with a semiconductor device, said board being able to use a silver or copper conductor having a good electro-conductivity; and an amorphous glass powder for said ceramic multilayer circuit board.

Abstract: Ceramic insulating substrate layers (1) for a multilayered ceramic wiring circuit board (3) consist essentially of crystals of mullite and sillimanite, non-crystalline silicon dioxide occupying the interstices between the crystals and magnesium oxide dissolved substantially in the crystals in solid solution and have a thermal expansion coefficient of 40-60.times.10.sup.-7 /.degree. C. and a dielectric constant below 6.7.

Abstract: Disclosed is a diffusion bonding method which can be applied to superalloys and comprises forming in advance an alloy layer containing an additional element or elements having a higher diffusion speed than that of the principal constituent element of a base metal and a lower melting point than that of the base metal on the joint surface of the base metal consisting of a heat-resistant superalloy based on Co, Ni, Fe, Ti or the like, and bringing the joint surfaces into contact so as to diffuse B.

Abstract: A ceramic insulating layer (2) for the multilayer ceramic circuit board (11) consists of 60 wt % of crystallized glass and 40 wt % of a filler such as silicon dioxide bonded by the crystallized glass, which consists of 6-15 wt % of lithium oxide, 70-90 wt % of silicon dioxide, 1-8 wt % of aluminum oxide, 1-5 wt % of alkaline metal oxide other than lithium oxide and 2-5 wt % of alkaline earth metal oxide. The sintered ceramic insulating layer (2) has a dielectric constant below 6.1 and a flexural strength above 150 MPa and is co-firable with a wiring conductor layer of such as gold, silver and copper.

Abstract: A ceramic multilayer circuit board comprising ceramic layers and wiring conductor layers laminated alternately, in which the ceramic layer has a thermal expansion coefficient lower than that of the wiring conductor and not lower than one half of that of the conductor layer and is formed from a glass which softens at a temperature not higher than the melting point of the wiring conductor layer; a semiconductor module having a high reliability in its solder joint part comprising said ceramic multilayer circuit board mounted with a ceramic carrier substrate being mounted with a semiconductor device, said board being able to use a silver or copper conductor having a good electro-conductivity; and an amorphous glass powder for said ceramic multilayer circuit board.