MONTE-CARLO CALCULATIONS OF FREE AMMONIA PRODUCTION IN DEOXYGENATED SOLUTIONS OF GLYCYLGLYCINE IRRADIATED BY X-RAYS AND CO-60 GAMMA-RAYS

Detailed-history Monte Carlo computer codes were used to simulate the formation, diffusion, and chemical reaction of free-radical species within deoxygenated aqueous solutions of glycylglycine irradiated by 250-kVp X rays and by 60Co γ rays. In one reaction, hydrated electrons react with the glycylglycine solute to produce unbound, or free, ammonia. This reaction is complete by 10-6 s within individual electron tracks for glycylglycine concentrations ≥0.025 M. For solute concentrations from 0.025 to 1.2 M, calculated G values of free ammonia are in excellent agreement with measured values. In addition, the computer model predicts a statistically significant difference between the G value of free ammonia produced under X irradiation and that produced under 60Co γ irradiation.