Some effects of temperature, dose rate, and scavenger additives in the radiolysis of air-free liquid CHCI3 are interpreted by means of a free-radical mechanism. The primary free radicals are shown to be CHC12• (G = 5.6 radicals/100 e.v.), Cl atoms (G = 5.4 atoms/100 e.v.), CC12 (G = 0.4 radical/100 e.v.), CC13• (G = 0.25 radical/100 e.v.), and H atoms (G = 0.2 atom/100 e.v.). Additional CC13 radicals are formed by reactions of CHC12 radicals, Cl atoms, and H atoms with CHC13, and the total yield of CC13 radicals exceeds Cr(CHCl2•) above -30°. A relatively broad and diffuse spatial distribution of primary radicals is proposed for consistency with the onset of dose rate effects at low dose rates, a low spur radical yield, and the high probability that the fate of virtually all electrons is dissociative electron attachment in irradiated CHC13. Effects of temperature in the radiolysis of solid CHC13 are also reported and discussed briefly.

Creep deformation of 0" sapphire was studied between 1600" and 1800°C at stresses up to 114 MN/m2. Microscopical evidence (dislocation structures observed by transmission electron microscopy (TEM) and by etch pits) suggested that Nabarro climb was the predominant deformation mechanism. Both the experimental creep rates and stress exponents were in good agreement with those predicted by this model. Although nonbasal dislocations with a I/:t <1101> Burgers vector were present, the good creep resistance of 0" sapphire was attributed to the difficulty of activating pyramidal slip.

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