2003 Volume 52 Issue 8 Pages 367-373
Using electron spin resonance (ESR) spectroscopy, we revealed the thermal decay process of radicals as induced by γ-ray irradiation on pepper. Upon irradiation, the satellite signals were newly generated at the symmetric positions of the organic free radical, i.e., the g=2.0 signal. By heat treatment, the satellite signals decreased exponentially to heating duration. The ESR signal of the pepper heated for more than 10 min was essentially the same as that before irradiation. In order to evaluate the radical decay during heating, we derived a time-dependent master equation. Based upon the general solution of the equation, we evaluated the time constant of the radical decay through the nonlinear least squares method.
