Calcium carbide, modifications

Calcium carbide CaC2 exists in at least four crystalline modifications whose occurrence depends on the temperature of formation and the presence of impurities. The tetragonal phase CaC2(I), which is stable between 298 and 720 K, is... 

Proximate Analysis.—Moisture and residual solvent, in the case of nitro-glycerine explosives, are determined by Marshall s modification of L. W. Dupre s method (L. W. Dupre, Chemiker Zeitung, 540, 1901, and Marshall, Journ. Soc. Chem. Ind., 154, 1904). P. V. Dupri (Analyst, I9°6> 31, 2I3) estimates water in the volatile matter by passing it through a layer of calcium carbide and measuring the acetylene generated. 

One out of four modifications of CaC2, so-called metastable calcium carbide CaC2-III, has been characterized using CPMAS. ... 

Zheng, L.P., Wang, Y, Wang, X.Y., An, H.F., and Yi, L.H. The effects of surface modification on the supercapacitive behaviors of carbon derived from calcium carbide. Journal of Materials Science 45, 6030-6037, 2010. 

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