Crystalline Oxygen-Containing Materials

1 Crystalline oxygen-containing materials. The structural chemistry of tin is complex because it can take different coordination numbers and also different oxidation states. Both these effects influence the shift, and need to be disentangled before the 

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V.V. Banik, O. V. Demirskaya and L.N. Chervonnaya, Fractional Separation of Oxygen-Containing Impurities in Sodium Iodide at Vacuum Distillation, Single-Crystalline Materials, Vol. Nil (Institute for Single Crystals, Kharkov, 1983) pp. 87-90. 

Such a blend is intended as a replacement for previous blends of polyamide and polyethylene used in gas tanks and other containers. These older blends were exposed to a mixture of hydrocarbons but now oxygenated solvents (e.g., methanol) have been added which cause an unacceptable reduction of barrier properties. A replacement technology is needed. Improved barrier properties in this design comes from increased crystallinity of the material brought about by controlling laminar thickness of polyethylene crystals and processing material under conditions which favor the crystallization of poly(vinylidene fluoride). 

Cobalt(Il) dicobalt(Ill) tetroxide [1308-06-17, Co O, is a black cubic crystalline material containing about 72% cobalt. It is prepared by oxidation of cobalt metal at temperatures below 900°C or by pyrolysis in air of cobalt salts, usually the nitrate or chloride. The mixed valence oxide is insoluble in water and organic solvents and only partially soluble in mineral acids. Complete solubiUty can be effected by dissolution in acids under reducing conditions. It is used in enamels, semiconductors, and grinding wheels. Both oxides adsorb molecular oxygen at room temperatures. 

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