Irradiation of Gaseous and Liquid Oxygen

Aviator's breathing oxygen was gamma irradiated in the gaseous and in the liquid states under a variety of controlled temperatures, pressures, times, and dose rates. It was then analyzed for ozone and nitrogen oxides. In gaseous oxygen, ozone reached a peak concentration with 10/sup 5/ rads total dose and then decreased to steady-state concentration with 10/sup 7/ rads total dose, regardless of temperature, pressure, or dose rate. The peak and the steady-state ozone concentrations increased with increasing dose rate and decreased with increasing temperature. In liquid oxygen, ozone concentration increased linearly with total dose, regardless of dose rate or magnitude of total dose. Minimum G values for ozone formation were nine for gaseousstate and six for liquid-state irradiations. An apparent activation energy calculated from these studies suggests that the maximum and the steady-state ozone concentrations are related to a secondary atom-molecule reaction. Nitrogen oxide yields were always small, but they seemer to be significant in their effects on the mechanism of ozon formation. (auth)