Abstract: A reactor containment vessel cooling technology for preventing the cooling capability and structural integrity of a reactor containment vessel cooling system from decreasing by lowering the temperature of water vapor and gases acquired by the reactor containment vessel cooling system is provided. Based on the technology, the present invention provides a reactor containment vessel cooling system that acquires water vapor in a reactor containment vessel by using water vapor pressure in the vessel as a drive force, condenses the acquired water vapor into condensate, and cools the reactor containment vessel with the condensate.

Abstract: A process for producing aluminum nitride powder by reacting nitrogen gas with a mixture of alumina and carbon is disclosed, in which a solid organic compound is added to the mixture.

Abstract: A process for producing an aluminum nitride powder by reacting a mixture of alumina and carbon with a nitrogen gas, wherein the mixture of alumina and carbon being contacted with a nitrogen-containing inert gas at a temperature of 1,000.degree. to 1,400.degree. C. at a pressure of not higher than 0.1 atmosphere before a reaction is started to form aluminum nitride.

Abstract: A nail lacquer remover of the transparent gel type, consisting essentially of: (1) 30-65% by weight of a carbonate selected from the group consisting of ethylene carbonate, propylene carbonate, butylene carbonate and glycerine carbonate; (2) 10-50% by weight of 1,3-dimethyl-2-imidazolidinone; (3) 0.2-20% by weight of hydroxypropyl cellulose; and (4) 13-40% by weight of water. The nail lacquer remover has low flammability, and does not cause drying and cracking of nails.