Disclosed is a process for producing a fluoride gas that can produces fluoride gases such as BF.sub.3, SiF.sub.4, GeF.sub.4, PF.sub.5 or AsF.sub.5 at a reduced production cost in a simple manner. The process is characterized in that a compound containing an atom, which, together with a fluorine atom, can form a polyatomic ion, is added to a hydrogen fluoride solution to produce the polyatomic ion in a hydrogen fluoride solution and to evolve a fluoride gas comprising the fluorine atom and the atom that, together with the fluorine atom, can form a polyatomic ion.

Disclosed is a process for producing a fluoride gas that can produces fluoride gases such as BF.sub.3, SiF.sub.4, GeF.sub.4, PF.sub.5 or AsF.sub.5 at a reduced production cost in a simple manner. The process is characterized in that a compound containing an atom, which, together with a fluorine atom, can form a polyatomic ion, is added to a hydrogen fluoride solution to produce the polyatomic ion in a hydrogen fluoride solution and to evolve a fluoride gas comprising the fluorine atom and the atom that, together with the fluorine atom, can form a polyatomic ion.

A method for the manufacture of highly purified .sup.68Ge material for radiopharmaceutical purposes. The invention particularly concerns the production of .sup.68Ge-API (API=Active Pharmaceutical Ingredient) solution complying with the Guidelines for good manufacturing practices (GMP). Starting material for the method of the present invention can be a .sup.68Ge stock solution of commercial or other origin as raw material. Such .sup.68Ge containing raw solutions are purified from potential metal and organic impurities originating from production processes. The radiochemical method disclosed is based on a twofold separation of .sup.68Ge from organic and metallic impurities with two different adsorbent materials. During the first separation phase .sup.68Ge is purified from both organic and metallic impurities by adsorption in germanium tetrachloride form, after which hydrolyzed .sup.68Ge is purified from remaining metallic impurities by cation exchange. The final .sup.68Ge-API-product e.g. fulfills the regulatory requirements for specifications of the GMP production of .sup.68Ge/.sup.68Ga generators.

A method for the manufacture of highly purified .sup.68Ge material for radiopharmaceutical purposes. The invention particularly concerns the production of .sup.68Ge-API (API=Active Pharmaceutical Ingredient) solution complying with the Guidelines for good manufacturing practices (GMP). Starting material for the method of the present invention can be a .sup.68Ge stock solution of commercial or other origin as raw material. Such .sup.68Ge containing raw solutions are purified from potential metal and organic impurities originating from production processes. The radiochemical method disclosed is based on a twofold separation of .sup.68Ge from organic and metallic impurities with two different adsorbent materials. During the first separation phase .sup.68Ge is purified from both organic and metallic impurities by adsorption in germanium tetrachloride form, after which hydrolyzed .sup.68Ge is purified from remaining metallic impurities by cation exchange. The final .sup.68Ge-API-product e.g. fulfills the regulatory requirements for specifications of the GMP production of .sup.68Ge/.sup.68Ga generators.

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.

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.

The present invention provides a light valve containing ABX.sub.3 perovskite particles; more specifically is related to a light valve containing halide ABX.sub.3 perovskite particles that can control light transmittance. The preferable halide ABX.sub.3 perovskite particles in this invention consist of A being at least one of Cs.sup.+, CH3NH3.sup.+, and Rb.sup.+, B being at least one of Pb.sup.2+, Ge.sup.2+, and Sn.sup.2+, and X being at least one of Cl.sup., Br.sup., and I.sup.. This kind of halide ABX.sub.3 perovskite particles were suspended in a liquid suspension to make a light valve with a light transmittance control, which discloses a completely new application for ABX.sub.3 perovskite materials.

Provided is a method and apparatus for secondary enrichment of germanium from low-grade lignite germanium concentrates in vacuum, and particularly a method and apparatus for secondary enrichment and recovery of germanium from low-grade lignite germanium concentrates with microwave heating in vacuum, which belongs to a germanium extraction method and apparatus in the field of metallurgy.

Provided is a method and apparatus for secondary enrichment of germanium from low-grade lignite germanium concentrates in vacuum, and particularly a method and apparatus for secondary enrichment and recovery of germanium from low-grade lignite germanium concentrates with microwave heating in vacuum, which belongs to a germanium extraction method and apparatus in the field of metallurgy.