Insulators, diamonds reactions

Single pulse, shock tube decomposition of acetic acid in argon inv olves the same pair of homogeneous, molecular first-order reactions as thermolysis (19). Platinum on grapliite catalyzes the decomposition at 500—800 K at low pressures (20). Ketene, methane, carbon oxides, and a variety of minor products are obtained. Photochemical decomposition yields methane and carbon dioxide and a number of free radicals, wliich have complicated pathways (21). Electron impact and gamma rays appear to generate these same products (22). Electron cyclotron resonance plasma made from acetic acid deposits a diamond [7782-40-3] film on suitable surfaces (23). The film, having a polycrystalline stmcture, is a useful electrical insulator (24) and widespread industrial exploitation of diamond films appears to be on the horizon (25). 

A diamond-coated cylinder of refractory metal (Nb, Mo, W, or Re) may replace the cylindrical ceramic insulators used in thermionic fuel elements (TFE) for space nuclear-power systems. A TFE converts the thermal energy from a nucleeu reaction into electrical energy and is designed to provide power to a spacecraft for as long as ten years. The unique properties of diamond would prevent power loss due to electrical leakage... 

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