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acetyleneЗначение термина acetylene в knolikacetylene - Acetylene acetylene - Hydrocarbon gas (C2H2), with a smell not unpleasant when pure but very unpleasant as commercially produced. Prepared by the action of water on calcium carbide, itself produced from coal and lime, it is a valuable illuminant and a fundamental material for the preparation of the hydrocarbon plastics, including the important vinyl and poly-vinyl series. The well-known polyvinyl chloride (P.V.C.) plastic is a combination of acetylene and hydrochloric acid polymerized under heat and catalysts. Acetylene and acetic acid are polymerized to form vinyl acetate. From acetylene is also produced a series of products used as solvents for plastics (e.g. acetone) or as "plasticizers," i.e. chemical agents that make cellulose products more flexible and suitable as plastics. When mixed with oxygen or air in certain proportions acetylene gas explodes with great violence with an enormous liberation of heat. This fact is made use of ia the oxy-acetylene flame, which has the extremely high temperature of over 3,000° C. and is used for welding and cutting metals. Acetylene is a strong illuminant giving a very white flame, a light source sixteen times greater than an equal volume of coal-gas. Its spectrum is very similar to that of sunlight. When liquefied and dissolved in acetone it can be compressed without risk (dissolved acetylene). Acetylene generators for indoor and outdoor lighting consist of carbide chambers, washers, gas holders, and purifiers. Copper piping must not be used owing to the formation of an explosive compound. Acetylene is particularly suitable for outdoor lighting for hand or contractors' lamps of from 20 to 2,500 candle power. See Calcium Carbide. Рядом со словом acetylene в knolik
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