Methane exposion properties

The epoxy resin formed by tetraglycidyl 4,4 -diamino diphenyl methane and 4,4 -diamino diphenyl sulfone was characterized by dynamic mechanical analysis. Epoxy specimens were exposed to varying dose levels of ionizing radiation (0.5 MeV electrons) up to 10,000 Hrads to assess their endurance in long-term space applications. Ionizing radiation has a limited effect on the mechanical properties of the epoxy. The most notable difference was a decrease of approximately 40°C in Tg after an absorbed dose of 10,000 Mrads. Sorption/desorption studies revealed that plasticization by degradation products was responsible for a portion of the decrease in Tg. 

The chloride is used to manufacture silicones, tetramethyl lead and triptane (2,2,3 trimethylbutane). Lesser uses include the manufacture of butyl rubber, higher halogenated methanes, methyl cellulose, quaternary ammonium compounds, methyl mercaptan, methionine, fungicides and pesticides (primarily the Me-arsenate herbicides). Recently the chlorinated fluorocarbons have replaced CH3CI as high volume refrigerants and propellants (ref. 32) Tables 12 and 13 list the chemical and physical properties and potential numbers of workers exposed to the monohalomethanes. 

By quantification of the oxygen content it was possible to estimate the thickness of the oxide layer, related to the exposed surface of Pd (whose size was estimated after complete reduction of the sample). It was observed that the more active catalysts had a larger number of oxygen layers which suggested the participation of bulk Pd in the reaction. Therefore, for methane oxidation, the Pd/Al2C>3 catalytic properties seem to be controlled by a redox mechanism, where the oxidation and reduction rates of the active phase depend on the size and stability of the Pd and PdO species. The small PdO particles seemed to be poorly reactive, due to their higher stability or to a greater interaction with the support. In fact, analysis of TPO and TPD data revealed that the small particles of PdO decompose at... 

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