A light valve containing ABX.sub.3 perovskite particles (200) suspended in a liquid suspension (300) that can control light transmittance is provided. The preferable ABX.sub.3 perovskite particles (200) are halide ABX.sub.3 perovskite particles wherein A is at least one of Cs.sup.+, CH.sub.3NH.sub.3.sup.+, and Rb.sup.+, B is at least one of Pb.sup.2+, Ge.sup.2+, and Sn.sup.2+, and X is at least one of Cl.sup., Br.sup., and I.sup.. Use of the light valve in the manufacture of a light control device and a method of controlling light transmittance by using the light valve are also provided.

A light valve containing ABX.sub.3 perovskite particles (200) suspended in a liquid suspension (300) that can control light transmittance is provided. The preferable ABX.sub.3 perovskite particles (200) are halide ABX.sub.3 perovskite particles wherein A is at least one of Cs.sup.+, CH.sub.3NH.sub.3.sup.+, and Rb.sup.+, B is at least one of Pb.sup.2+, Ge.sup.2+, and Sn.sup.2+, and X is at least one of Cl.sup., Br.sup., and I.sup.. Use of the light valve in the manufacture of a light control device and a method of controlling light transmittance by using the light valve are also provided.

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.

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 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%.

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%.

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.

Binary and ternary eutectic mixtures and corresponding electrolytes are disclosed. In some embodiments, binary eutectic mixtures and electrolytes each include a first salt, X1.sup.+Y1.sup., and a second salt, X2.sup.+Y2.sup., wherein each of X1.sup.+ and X2.sup.+ is an alkali metal cation and X1.sup.+ is different from X2.sup.+; and each of Y1.sup. and Y2.sup. is a sulfonimide anion and Y1.sup. is different from Y2.sup.. In ternary eutectic mixtures and electrolytes further include a third salt, X3.sup.+Y3.sup., wherein X3.sup.+ is different from each of X1.sup.+ and X2.sup.+. In some embodiments, the eutectic mixtures and electrolytes have melting points in a range of about 5 C. to about 70 C. Electrochemical devices containing such eutectic-mixture electrolytes are also disclosed.