Thermoluminescent properties of high dielectric materials were examined before and after exposure to 2450 MHz microwave radiation. Fading of low temperature peaks was significantly greater in phosphors exposed to microwaves than in oven heated controls.

The effects of temperature upon the radiation-induced absorbance spectra of cobalt borosilicate glass dosimeters were investigated by subjecting dosimeters to different combinations of preexposure, exposure, and post exposure temperature environments. The dosimeters were exposed to 2 × 104, 105, 5 × 105 and 106R in a 60Co irradiator, and absorbance measurements were taken at 3000 A, 3750 A and 5000 A over a four month study period. No significant difference in absorbance was produced by exposure temperatures within a 0°C to 100°C range, but exposure temperatures beyond 150°C resulted in decreases in absorbance levels. The radiation-induced coloration faded linearly with the logarithm of time following exposure with the fading rates being dependent upon exposure, exposure temperature, storage temperature, and the wavelength at which the absorbance spectra were measured. The coloration was completely removed by a 1 hr heat treatment at 500°C. This clarification treatment did not affect the radiation response of the dosimeters given subsequent exposures.

An existing histochemical method was adapted to a-particle autoradiography to provide a means of quantifying acetylcholinesterase inhibition at myoneu.ral junctions. The aparticles were emitted from polonium 210 which was present in the precipitate after staining. A technique was designed for counting areas of dense a-particle tracks on the autoradiograms which corresponded to sites of acetylcholinesterase activity. An experiment was performed which showed that the track production rate was consistent for several diaphragm sections when incubated under identical conditions with no inhibitor. Tissue sections of this type, representing zero inhibition, were used as controls for inhibitor studies. It was also demonstrated that the track production rate was constant during the different exposure times used in the inhibition study. Diisopropylfluorophosphate was used to evaluate the autoradiographic method of quantifying acetylcholinesterase inhibition. A plot of log inhibitor concentration against percentage inhibition resulted in a smooth sigmoidal curvewhich istypical of irreversible inhibitors.