Abstract: A porous sintered body is composed of a perovskite-type composite oxide, wherein A-site of the composite oxide are occupied by one or more kinds of first metallic elements selected from the group consisting of calcium and strontium, one or more kinds of second metal elements selected from the group consisting of rare earth elements and yttrium excluding lanthanum and cerium, and lanthanum, the above one or more kinds of the first metallic elements amount to 5 to 70 mol % of the A-sites, and manganese is contained in B-sites of the composite oxide.

Abstract: A method for operating a power generator in which a solid oxide fuel cell is used as a power-generating element and an air electrode of the solid oxide fuel cell is composed of lanthanum manganite, the method involving the step of setting a heating rate and a cooling rate at least in a temperature range of 800.degree. C. to 900.degree. C. at not less than 3.degree. C./min. when the fuel cell is heated up to an operating temperature at the time of starting the power generator and when the fuel cell is cooled from the operating temperature at the time of stopping the power generator. Alternatively, the method involves the step of setting a partial pressure of oxygen, at least in a temperature range of 800.degree. C. to 900.degree. C., in an atmosphere to which the air electrode is exposed, to at not less than 10.sup.-15 arms but not more than 10.sup.

Abstract: A porous sintered body composed mainly of lanthanum manganite in which a part of lanthanum atoms at A-sites of the lanthanum manganite are substituted by atoms of a metal selected from the group consisting of alkaline earth metals and rare earth metals. The dimensional shrinkage amount of the porous sintered body in heat cycling between room temperature and 1,000.degree. C. is not more than 0.01% per one heat cycle.

Abstract: In order to improve a reliability of a glass joint body, first ceramic member and second ceramic member are connected by using (a) glass consisting of 10.about.65 wt % of SiO.sub.2, 30 wt % or less of Na.sub.20, and the balance of B.sub.2 O.sub.3 and Al.sub.2 O.sub.3, (b) glass including less than 10 wt % of SiO.sub.2, and 30.about.80 wt % of B.sub.2 O.sub.3, (c) glass including substantially none of SiO.sub.2, and 30.about.80 wt % of B.sub.2 O.sub.3, or (d) glass consisting of 10.about.65 wt % of SiO.sub.2, 20 wt % or less of Na.sub.2 O, 30 wt % or less of Al.sub.2 O.sub.3, 20 wt % or less of MgO, and the balance of B.sub.2 O.sub.3.

Abstract: A composite ceramic material that is stable and shows a high strength in the temperature range of room temperature to 1600.degree. C. as well as has a toughness high-enough to be used as structural material and a process for producing it are provided. This composite ceramic material is composed of a matrix substantially made up of Si.sub.3 N.sub.4 and Si.sub.2 N.sub.2 O and a dispersion phase substantially made up of SiC where the matrix contains 0.05% by weight or less of metal element impurities such as Al, Ca and Fe. SiC grains or fibers are dispersed in the dense matrix made up of Si.sub.3 N.sub.4 and Si.sub.2 N.sub.2 O fine grains, which are substantially free from element impurities except Si, C and O. According to one aspect of this invention, this ceramic material is produced by Si.sub.3 N.sub.4 with SiO.sub.2 to form matrix powders that contain 0.

Abstract: A multilayered packaging material having good piercing resistance and tearability and being excellent in appearance, transparency and so forth, can be produced by orienting multilayered structure which is composed of a polyamide resin layer and other thermoplastic resin layer(s) at a monoaxially stretching ratio of 1.5- to 7.0-fold in such a manner that the thickness of the polyamide resin layer is 3 to 30 .mu.m and the thickness(es) of the other thermoplastic resin layer(s) is (are) at least twice as much as that of the polyamide resin layer.

Abstract: In one aspect of the invention, there is provided a molded article of crystalline thermoplastic resin with high gas barrier property of which the resin has crystalline and non-crystalline regions, the enhancing effect on gas barrier property of uniaxial-uniplanar orientation of the crystal axis direction of crystallites of said crystalline regions being used and the crystallites orientation being optimized by specific conditions. In another aspect of the invention, the molded article of the first aspect of the invention is further annealed to increase the crystallinity of the crystalline regions.

Abstract: Silicon nitride sintered bodies are disclosed which contain silicon carbide therein and in which intergranular phases between silicon nitride particles are substantially crystallized. Further, a manufacturing method of the sintered bodies is disclosed, in which a silicon carbide powdery raw material is used as an additive when preparing raw powders and the intergranular phases are crystallized during a temperature descending stage following a firing. Silicone carbide effectivley promotes densification of the structure of the sintered body and crystallization of the intergranular phases, thereby making it possible to provide the sintered bodies having intergranular phases with little glass phases uncrystallized and excellent high-temperature strengths.

Abstract: A process for manufacturing MgO-based .beta."-alumina sintered bodies from a starting powder comprising an MgO-based .beta."-alumina as a main ingredient, through shaping and firing, in which process shaped bodies before firing contain 0.3.about.5 wt. %, preferably 1.about.3 wt. %, of Na aluminate. The resulting sintered bodies are high in density, ionic conductivity and strength and useful for solid electrolytes, for example, of sodium sulfur cells.

Abstract: In order to improve the reliability of a glass joint body, a first ceramic member and a second ceramic member are connected by using (a) glass consisting of 10.about.65 wt % of SiO.sub.2, 30 wt % or less of Na.sub.2 O, and the balance of B.sub.2 O.sub.3 and Al.sub.2 O.sub.3, (b) glass including less than 10 wt % of SiO.sub.2, and 30.about.80 wt % of B.sub.2 O.sub.3, (c) glass including substantially none of SiO.sub.2, and 30.about.80 wt % of B.sub.2 O.sub.3, or (d) glass consisting of 10.about.65 wt % of SiO.sub.2, 20 wt % or less of Na.sub.2 O, 30 wt % or less of Al.sub.2 O.sub.3, 20 wt % or less of MgO, and the balance of B.sub.2 O.sub.3.

Abstract: A beta alumina sintered body having a wide optimum sintering temperature range and a high sodium ion conductivity includes 8.0-10.0 wt % of sodium oxide, 3.0-5.5 wt % of magnesium oxide, 0.01-1.0 wt % of tin oxide, and the remainder of aluminum oxide. This sintered body is manufactured by mixing raw materials including 8.0-10.0 wt % of sodium oxide, 3.0-5.5 wt % of magnesium oxide, 0.01-1.0 wt % of tin oxide, and the remainder of aluminum oxide to obtain raw material powder; forming the raw material powder to obtain a formed body; and sintering the formed body to obtain a beta alumina sintered body.

Abstract: Silicon nitride sintered bodies are disclosed which contain silicon carbide therein and in which intergranular phases between silicon nitride particles are substantially crystallized. Further, a manufacturing method of the sintered bodies is disclosed, in which a silicon carbide powdery raw material is used as an additive when preparing raw powders and the intergranular phases are crystallized during a temperature descending stage following a firing. Silicon carbide effectively promotes densification of the structure of the sintered body and crystallization of the intergranular phases, thereby making it possible to provide the sintered bodies having intergranular phases with little glass phases uncrystallized and excellent high-temperature strengths.

Abstract: A beta alumina sintered body having no tantalum component in an intergranular phase is manufactured by mixing raw materials consisting essentially of 8.0-10.0 wt % of sodium oxide, 3.0-5.5 wt % of magnesium oxide and/or 0.1-2.0 wt % of lithium oxide, 0.01-0.5 wt % of tantalum oxide, and the remainder of aluminum oxide to obtain raw material powders; forming the raw material powders to obtain a formed body; and sintering the formed body.

Abstract: A silicon nitride sintered member including a silicon nitride sintered body and a dense silicon nitride coating layer covering the surface of the silicon nitride sintered body. An intergranular phase of the silicon nitride sintered body is substantially composed of crystals.

Abstract: A silicon carbide sintered member is coated at its surface with zirconia, whereby the heat insulating properties are considerably improved.

Abstract: A silicon nitride sintered member comprises a silicon nitride sintered body and a zirconia layer coated onto the surface of the silicon nitride sintered body. The zirconia layer is preferably coated onto the surface of the silicon nitride sintered body through plasma spraying. The zirconia-coated silicon nitride sintered member has both high strength at high temperatures and excellent heat insulating property.

Abstract: A silicon carbide sintered body containing given amounts of Mg, B and free carbon and having a density of not less than 2.80 g/cm.sup.3 is produced by adding given amounts of magnesium boride and carbon to silicon carbide powder having an average grain size of not more than 5 .mu.m, shaping and firing at 1,900.degree..about.2,300.degree. C. under vacuum or in an inert gas atmosphere.

Abstract: A silicon nitride sintered body having an improved oxidation resistance or wear resistance has in its surface a coating of silicon carbide. Particularly, the coating of silicon carbide is formed by CVD process.

Abstract: A silicon nitride sintered body having high oxidation resistance and high-temperature strength is produced by starting from silicon nitride powder adjusted so as to have an oxygen content of 4.5-7.5 wt % as converted into SiO.sub.2. The sintered body has a molar ratio of metal ion (M) to oxygen ion (O) within a range of M:O=1.2.about.1:3 and contains no crystal of YSiO.sub.2 N form.

Abstract: A silicon nitride sintered member comprises a silicon nitride sintered body and a zirconia layer coated onto the surface of the silicon nitride sintered body. The zirconia layer is preferably coated onto the surface of the silicon nitride sintered body through plasma spraying. The zirconia-coated silicon nitride sintered member has both high strength at high temperatures and excellent heat insulating property.