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.

Described are luminescent components with excellent performance and stability. The luminescent components comprise a first element 1 including first luminescent crystals 11 from the class of perovskite crystals, embedded a first polymer P1 and a second element 2 comprising a second solid polymer composition, said second polymer composition optionally comprising second luminescent crystals 12 embedded in a second polymer P2. Polymers P1 and P2 differ and are further specified in the claims. Also described are methods for manufacturing such components and devices comprising such components.

Hydrometallurgical processes are provided for the recovery of metal values, including cesium, from epithermal mineral deposits, including pharmacosiderite-containing ores. Aspects of the process involve the preferential formation of a cesium alum, and preparation of cesium hydroxide from the cesium alum.

Hydrometallurgical processes are provided for the recovery of metal values, including cesium, from epithermal mineral deposits, including pharmacosiderite-containing ores. Aspects of the process involve the preferential formation of a cesium alum, and preparation of cesium hydroxide from the cesium alum.

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.

Non-hygroscopic brazing fluxes, methods for producing non-hygroscopic brazing fluxes, and methods for producing hydrated cesium aluminum fluorides are provided. An exemplary method for producing a non-hygroscopic brazing flux includes preparing a mixture including aluminum, cesium, and fluorine. The prepared mixture has an aluminum:cesium:fluorine molar ratio of about (1):(1.1-1.2):(4.0-4.2). The method further includes drying the mixture at a temperature higher than about 90 C. to form a product comprising at least about 20 mass percent hydrated cesium aluminum fluoride, based on the total mass of the product.

An antibacterial material containing composite tungsten oxide fine particles, which is represented by a general formula MxWyOz.

Provided are a hole transport material composite including a lead-free perovskite (Cs.sub.2SnI.sub.6), a liquid ionic conductor and a solvent that is a solid at a room temperature, a solar cell, and a method of manufacturing the lead-free perovskite-based hole transport material composite.

Provided are a hole transport material composite including a lead-free perovskite (Cs.sub.2SnI.sub.6), a liquid ionic conductor and a solvent that is a solid at a room temperature, a solar cell, and a method of manufacturing the lead-free perovskite-based hole transport material composite.

A method for producing ethylene oxide comprising: a) providing one or more feed components, wherein the one or more feed components contains at least ethylene obtained by dehydrating ethanol; b) contacting the one or more feed components with an ethylene oxide catalyst bed disposed in a reactor tube, the ethylene oxide catalyst bed comprising: (1) an upstream ethylene oxide catalyst having a first cesium concentration and (2) a downstream ethylene oxide catalyst having a second cesium concentration, wherein the first cesium concentration is higher than the second cesium concentration.