Abstract: A device for confining leaks of one or more gases contained in a gas cylinder, which comprises a shroud made of a flexible and nonflammable material which is inert with respect to the gas or gases contained in the cylinder and designed to partially envelope said cylinder, wherein said shroud has an opening provided with means for sealing said shroud to the surface of the cylinder and wherein the shroud is provided with an outlet coupling connected to a line for removing one or more of the gases to a means for neutralizing said one or more gases.

Abstract: A high porosity silicocalcareous mass is obtained by using in at least partial replacement of the usual silica, amorphous ultrafine synthetic silica particles having a specific surface between 150 and 300 m.sup.2 per gram, and a high absorption capacity, and optionally adding nonreactive synthetic fiber of either inorganic or organic origin to the mixture containing the particles. The high-porosity silicocalcareous mass can be used as a lining material for containers, which are intended for storing liquified or dissolved gases and also as an insulation material, such as sound insulation in building construction.

Abstract: A fuel mixture, which contains by volume 15 to 25% acetylene, 5 to 17% C.sub.3 hydrocarbon, preferably propylene, and the remainder ethylene. This ternary fuel having a fairly constant acetylene content, is suitable in applications pertaining to assembly, flame heat treatment, flame metal spraying and disintegration of inorganic compounds or cements.

Abstract: A high porosity silicocalcareous mass is obtained by using in at least partial replacement of the usual silica, amorphous ultrafine synthetic silica particles having a specific surface between 150 and 300 m.sup.2 per gram, and a high absorption capacity, and optionally adding nonreactive synthetic fibers of either inorganic or organic origin to the mixture containing the particles. The high-porosity silicocalcareous mass can be used as a lining material for containers, which are intended for storing liquified or dissolved gases and also as an insulation material, such as sound insulation in building construction.

Abstract: A silicocalcareous mass with high porosity is obtained by using, in at least partial replacement of the usual silica, ultrafine synthetic silica with a large specific surface of 200 to 500 m.sup.2 per gram to a paste of lime and silica, and possibly adding nonreactive synthetic fibers of organic or inorganic origin. The silicocalcareous mass with high porosity can be used in the field of lining materials for containers intended to store dissolved gases and in the field of insulation materials.

Abstract: A stable cryogenic fuel mixture containing 25 to 30% by volume of acetylene, 61 to 72% by volume of ethylene and 3 to 9% by volume of a C.sub.3 hydrocarbon preferably propylene. This fuel mixture having a density in the gaseous state, which is less than the density of air, is particularly suited for use in welding and assembly operations.

Abstract: A fuel mixture, comprising from 10 to 60 mols % acetylene and from 40 to 90 mols % ethylene, is prepared by mixing the two constituents in the gaseous phase at a pressure slightly above atmospheric pressure and at a temperature ranging from -25.degree. C. to +20.degree. C.