Abstract: A sintered body comprises zirconia including a stabilizer element dissolved therein and a lanthanoid element dissolved therein, the lanthanoid element having an ionic radius larger than the atomic radius of zirconium. The content of monoclinic zirconia after a hydrothermal treatment at 140° C. for 24 hours is less than 25%. The sintered body includes a spinel compound including aluminum and a coloring element.

Abstract: The present invention provides a composition that includes a silicotitanate that has a sitinakite structure, the composition having higher cesium adsorptivity than conventional compositions. The present invention also provides a production method for the composition that includes a silicotitanate that has a sitinakite structure. The production method does not require the use of hazardous or deleterious materials, can generate a product using a compound that is easily acquired, and can use a general-purpose autoclave. Also provided is a silicotitanate composition that has higher strontium adsorptivity than the present invention. Provided is a silicotitanate composition that contains niobium and a silicotitanate that has a sitinakite structure, the composition having at least two or more diffraction peaks selected from the group consisting of 2?=8.8°±0.5°, 2?=10.0°±0.5°, and 2?=29.6°±0.5°.

Abstract: A zirconia sintered body comprising 3.0 wt % or more and 30.0 wt % or less of aluminum in terms of Al2O3 and a remainder is zirconia containing 2 mol % or more and 4 mol % or less of erbia, in which the zirconia sintered body includes grains of aluminum oxide, and a total light transmittance with respect to a D65 light source at a sample thickness of 1.0 mm is 10% or less.

Abstract: A zirconia sintered body contains aluminum, cobalt, and manganese and a remaining portion consisting of yttria-containing zirconia. In an oxide exchange, aluminum content is 5.0 wt % or more and 30.0 wt % or less, cobalt content is 0.1 wt % or more and 2.0 wt % or less, and manganese content is 0.5 wt % or more and 7.0 wt % or less.

Abstract: A zirconia sintered body comprising 3.0 wt % or more and 30.0 wt % or less of aluminum in terms of Al2O3 and a remainder is zirconia containing 2 mol % or more and 4 mol % or less of erbia, in which the zirconia sintered body includes grains of aluminum oxide, and a total light transmittance with respect to a D65 light source at a sample thickness of 1.0 mm is 10% or less.

Abstract: Provided are: a silver-carrying zeolite molded article in which aggregation of silver is inhibited and which has excellent capability of dispersing silver, when compared to conventional silver-carrying zeolite molded articles; and a method for producing the silver-carrying zeolite molded article. In the silver-carrying zeolite molded article, the molar ratio of Si/Al2 is 2.0-3.0, the molar ratio of (alkali metal+Ag)/Al is 0.9-1.1, the total amount of SiO2, Al2O3, Ag2O, and alkali metal oxides is 90 wt % or more, the contained amount of silver ions is 5 wt % or more, and only a single type of zeolite is contained. The molded article can be produced by subjecting a zeolite molded article having zeolite purity of 90% or more to an ion exchange treatment using a silver-containing aqueous solution.

Abstract: A zirconia sintered body contains aluminum, cobalt, and manganese and a remaining portion consisting of yttria-containing zirconia. In an oxide exchange, aluminum content is 5.0 wt % or more and 30.0 wt % or less, cobalt content is 0.1 wt % or more and 2.0 wt % or less, and manganese content is 0.5 wt % or more and 7.0 wt % or less.

Abstract: The present invention provides a composition that includes a silicotitanate that has a sitinakite structure, the composition having higher cesium adsorptivity than conventional compositions. The present invention also provides a production method for the composition that includes a silicotitanate that has a sitinakite structure. The production method does not require the use of hazardous or deleterious materials, can generate a product using a compound that is easily acquired, and can use a general-purpose autoclave. Also provided is a silicotitanate composition that has higher strontium adsorptivity than the present invention. Provided is a silicotitanate composition that contains niobium and a silicotitanate that has a sitinakite structure, the composition having at least two or more diffraction peaks selected from the group consisting of 2?=8.8°±0.5°, 2?=10.0°±0.5°, and 2?=29.6°±0.5°.

Abstract: The present invention provides a composition that includes a silicotitanate that has a sitinakite structure, the composition having higher cesium adsorptivity than conventional compositions. The present invention also provides a production method for the composition that includes a silicotitanate that has a sitinakite structure. The production method does not require the use of hazardous or deleterious materials, can generate a product using a compound that is easily acquired, and can use a general-purpose autoclave. Also provided is a silicotitanate composition that has higher strontium adsorptivity than the present invention. Provided is a silicotitanate composition that contains niobium and a silicotitanate that has a sitinakite structure, the composition having at least two or more diffraction peaks selected from the group consisting of 2?=8.8°±0.5°, 2?=10.0°±0.5°, and 2?=29.6°±0.5°.

Abstract: Provided are: a silver-carrying zeolite molded article in which aggregation of silver is inhibited and which has excellent capability of dispersing silver, when compared to conventional silver-carrying zeolite molded articles; and a method for producing the silver-carrying zeolite molded article. In the silver-carrying zeolite molded article, the molar ratio of Si/Al2 is 2.0-3.0, the molar ratio of (alkali metal+Ag)/Al is 0.9-1.1, the total amount of SiO2, Al2O3, Ag2O, and alkali metal oxides is 90 wt % or more, the contained amount of silver ions is 5 wt % or more, and only a single type of zeolite is contained. The molded article can be produced by subjecting a zeolite molded article having zeolite purity of 90% or more to an ion exchange treatment using a silver-containing aqueous solution.

Abstract: The present invention provides a composition that includes a silicotitanate that has a sitinakite structure, the composition having higher cesium adsorptivity than conventional compositions. The present invention also provides a production method for the composition that includes a silicotitanate that has a sitinakite structure. The production method does not require the use of hazardous or deleterious materials, can generate a product using a compound that is easily acquired, and can use a general-purpose autoclave. Also provided is a silicotitanate composition that has higher strontium adsorptivity than the present invention. Provided is a silicotitanate composition that contains niobium and a silicotitanate that has a sitinakite structure, the composition having at least two or more diffraction peaks selected from the group consisting of 2?=8.8°±0.5°, 2?=10.0°±0.5°, and 2?=29.6°±0.5°.

Abstract: [Problem] To provide a strontium ion-exchanged clinoptilolite having excellent nitrogen-absorbing properties; and a method for producing the strontium ion-exchanged clinoptilolite. [Solution] Synthetic clinoptilolite having a strontium ion at an ion exchange site thereof is useful as a nitrogen adsorbent. The synthetic clinoptilolite can be produced by bringing a solution containing a strontium ion into contact with synthetic clinoptilolite under ambient pressure to cause ion exchange.

Abstract: [Problem] To provide a strontium ion-exchanged clinoptilolite having excellent nitrogen-absorbing properties; and a method for producing the strontium ion-exchanged clinoptilolite. [Solution] Synthetic clinoptilolite having a strontium ion at an ion exchange site thereof is useful as a nitrogen adsorbent. The synthetic clinoptilolite can be produced by bringing a solution containing a strontium ion into contact with synthetic clinoptilolite under ambient pressure to cause ion exchange.

Abstract: Novel iron sulfides having excellent durability and excellent treating properties of heavy metals, processes for producing the iron sulfides, iron sulfide mixture, a heavy metal treating agent containing either of these novel iron sulfides as an effective component, and a method by which wastes containing various heavy metals are treated with the heavy metal treating agent are disclosed. The iron sulfide having a mackinawite structure which contains FeMxNySz wherein M represents an alkaline earth metal, N represents an alkali metal, and x, y and z, indicating the molar proportions of the respective elements, represent numbers satisfying 0.01<x?0.5, y?0.2 and 0.7?z?1.4, as an essential component.

Abstract: Novel iron sulfides having excellent durability and excellent treating properties of heavy metals, processes for producing the iron sulfides, iron sulfide mixture, a heavy metal treating agent containing either of these novel iron sulfides as an effective component, and a method by which wastes containing various heavy metals are treated with the heavy metal treating agent are disclosed. The iron sulfide having a mackinawite structure which contains FeMxNySz wherein M represents an alkaline earth metal, N represents an alkali metal, and x, y and z, indicating the molar proportions of the respective elements, represent numbers satisfying 0.01<x≦0.5, y≦0.2 and 0.7≦z≦1.4, as an essential component.

Abstract: Novel iron sulfides having excellent durability and excellent treating properties of heavy metals, processes for producing the iron sulfides, iron sulfide mixture, a heavy metal treating agent containing either of these novel iron sulfides as an effective component, and a method by which wastes containing various heavy metals are treated with the heavy metal treating agent are disclosed. The iron sulfide having a mackinawite structure which contains FeMxNySz wherein M represents an alkaline earth metal, N represents an alkali metal, and x, y and z, indicating the molar proportions of the respective elements, represent numbers satisfying 0.01<x≦0.5, y≦0.2 and 0.7≦z≦1.4, as an essential component.

Abstract: Novel iron sulfides having excellent durability and excellent treating properties of heavy metals, processes for producing the iron sulfides, iron sulfide mixture, a heavy metal treating agent containing either of these novel iron sulfides as an effective component, and a method by which wastes containing various heavy metals are treated with the heavy metal treating agent are disclosed. The iron sulfide having a mackinawite structure which contains FeMxNySz wherein M represents an alkaline earth metal, N represents an alkali metal, and x, y and z, indicating the molar proportions of the respective elements, represent numbers satisfying 0.01<x≦0.5, y≦0.2 and 0.7≦z≦1.4, as an essential component.

Abstract: A fine low silica faujasite type zeolite of high purity, having a faujasite single phase as measured by X-ray diffractometry, wherein the SiO2/Al2O3 molar ratio is from 1.9 to 2.1, the water adsorption in the form of Na-type is at least 35.0%, and the primary particle size is at least 0.05 &mgr;m and less than 1.0 &mgr;m. A process for producing the low silica faujasite type zeolite by mixing and gelling a solution containing an aluminate and a solution containing a silicate, followed by aging and crystallization, wherein after the gelling and/or at the initial stage of the aging, a solution having a set composition and preliminary aged at recited conditions is added in an amount of from 0.03 to 10% as Al2O3.

Abstract: A novel heat-resistant low-silica zeolite, an industrial production process, and uses of the low-silica zeolite are provided. The heat-resistant low-silica zeolite contains Si and Al in a molar ratio of SiO.sub.2 /Al.sub.2 O.sub.3 ranging from 1.9 to 2.1, and has sodium and/or potassium as metal cation, wherein the low-silica zeolite contains low-silica faujasite type zeolite at a content of not lower than 88%, and has a thermal decomposition temperature ranging from 870.degree. C. to 900.degree. C. in the air. The process for producing the heat-resistant low-silica zeolite comprises mixing a solution containing an aluminate with another solution containing a silicate, allowing the resulting mixture to gel, and aging the resulting gel, at the temperature of from 0.degree. C. to 60.degree. C., to prepare a slurry having a viscosity ranging from 10 to 10000 cp and containing amorphous aluminosilicate having a specific surface area of not less than 10 m.sup.2 /g with an SiO.sub.2 /Al.sub.2 O.sub.

Abstract: Disclosed are high purity low-silica faujasite type zeolite showing a faujasite single phase on X-ray diffraction, having a SiO.sub.2 /Al.sub.2 O.sub.3 molar ratio of 1.9 to 2.1 and a water adsorption of 35.0% by weight or more when converted to the Na type, and comprising particles having smaller primary particle size and particles having larger primary particle size, wherein the primary particle size of the smaller particles is from 1 .mu.m to 8 .mu.m, the primary particle size of the larger particles is from 5 .mu.m to 15 .mu.m, and the particles having smaller primary particle size accounts for 90% or more of the total particle number; and a method for producing low-silica faujasite type zeolite having a SiO.sub.2 /Al.sub.2 O.sub.3 molar ratio of 1.9 to 2.