A heat-insulating transparent PVC sheet is formed from a PVC substrate having a thickness of 0.02-2.0 mm and contains heat-insulation pastes evenly distributed over the PVC substrate, since the heat-insulation paste contains an essential component of wolfram cesium powder (WCs) with a chemical formula of Cs.sub.XN.sub.YWO.sub.3-ZCl.sub.C and having a particle size of 0.005-2 m, the heat-insulating transparent PVC sheet has an excellent weatherability, and particularly before and after tested in 300-hour service life in line with ASTM G-154 specification, has a physical property of weatherability decay rate (%) small than 4%.

The present application discloses a thermoelectric material, which contains CsAg.sub.5Te.sub.3 crystal material. At 700K, the thermoelectric material has an optimum dimensionless figure-of-merit ZT as high as 1.6 and a high stability, and the thermoelectric material can be recycled. The present application also discloses a method for preparing the CsAg.sub.5Te.sub.3 crystal material. The CsAg.sub.5Te.sub.3 crystal material is one-step synthesized by a high-temperature solid-state method, using a raw material containing Cs, Ag and Te, so that the high-purity product is obtained while the synthesis time is greatly shortened.

A transparent polyester film has low visible light transmittance of 5-50% by JIS K7705 testing standard and a high infrared-blocking rate of at least 90% by JIS R3106 testing standard, which is extruded from a kind of polyester resins obtained from 5-40 wt % of nanoparticle-based thermal insulation slurry and/or 0.005-0.1 wt % of nanoparticle-based black pigment slurry by weight of and to react with the polymerization materials to completely perform an esterification and a polycondensation, wherein the thermal insulation nanoparticle has a chemical formula of Cs.sub.XN.sub.YWO.sub.3-ZCl.sub.C with an average particle size of 10-90 nm and the nanoparticle-based black contains carbon black particles having a particle size of 20-80 nm.

The present invention relates to a method for removing cesium in a clay mineral using hydrogen peroxide. According to the present invention, cesium in a clay mineral is removed using hydrogen peroxide, which serves to induce interlayer expansion of the clay mineral to allow a cation to easily enter an interlayer of the clay mineral, and thus cesium desorption efficiency can be further improved. Also, the method according to the present invention can be efficiently used to restore soil in residential areas widely contaminated with a radionuclide when a major accident such as Fukushima nuclear accident occurs as well as various sites of atomic energy facilities contaminated with a radionuclide. Also, since radiation-contaminated soil is treated with only hydrogen peroxide and cations, secondary environmental pollution caused by wastes can be significantly reduce and the waste disposing cost can also be saved.

To concentrate metals such as gallium from ore which is extracted from mines or used electronic components while suppressing the quantity of waste liquid generated is difficult. A first solid metal compound which contains a metal selected from a group consisting of gallium, indium, germanium, tellurium, and cesium at a first metal content in a mixture of the first solid metal compound is reduced to form a gaseous metal compound, the gaseous metal compound is oxidized to form a second solid metal compound, and the second solid metal compound is collected at a second metal content which is higher than the first metal content.

To concentrate metals such as gallium from ore which is extracted from mines or used electronic components while suppressing the quantity of waste liquid generated is difficult. A first solid metal compound which contains a metal selected from a group consisting of gallium, indium, germanium, tellurium, and cesium at a first metal content in a mixture of the first solid metal compound is reduced to form a gaseous metal compound, the gaseous metal compound is oxidized to form a second solid metal compound, and the second solid metal compound is collected at a second metal content which is higher than the first metal content.

An alkali-metal dispenser to dispense highly pure rubidium in a high-vacuum environment while not negatively impacting the high-vacuum pressure level. The alkali-metal dispenser is operable in various vapor-deposition applications or to provide a highly pure elemental-alkali metal in cold-atom magneto-optical traps.

A member for hydrogen production includes a ceramic composite in which a plurality of ceramic particles having an average particle diameter ranging from 5 nm to 200 nm are dispersed in a porous insulator having a different component from the ceramic particles. The ceramic particles comprise at least one substance selected from the group consisting of AXO.sub.3 (where 01, A: at least one of rare earth elements, alkaline earth elements, and alkali metal elements, X: at least one of transition metal elements and metalloid elements, and O: oxygen), cerium oxide, and zirconium oxide as a main component.

A member for hydrogen production includes a ceramic composite in which a plurality of ceramic particles having an average particle diameter ranging from 5 nm to 200 nm are dispersed in a porous insulator having a different component from the ceramic particles. The ceramic particles comprise at least one substance selected from the group consisting of AXO.sub.3 (where 01, A: at least one of rare earth elements, alkaline earth elements, and alkali metal elements, X: at least one of transition metal elements and metalloid elements, and O: oxygen), cerium oxide, and zirconium oxide as a main component.

A luminescent composite material and a preparation method therefor. The luminescent composite material is prepared by mixing a precursor of a quantum dot and an oxide or a precursor thereof followed by high-temperature calcination. Compared with traditional methods, the method provided herein is a simple and low-cost synthesis process without using solvents, and is suitable for large-scale production. The luminescent composite material has high quantum efficiency, luminous intensity and luminous color purity and good photothermal stability, which can provide basis for theoretical research and applications of the luminescent composite material in high-performance photoluminescence devices, lasers and nonlinear optical devices.