An increase behavior of radicals in black pepper induced by the γ-ray irradiation was analyzed using electron spin resonance (ESR) spectroscopy. A sharp signal at g = 2.0, observed in the ESR spectrum of pepper due to organic free radicals produced by γ-ray irradiation, in-creased exponentially in the early stage of heating procedure and then leveled off at a certain value. The increase behavior was analyzed following to a first order differential equation, and obtained a general solution under the restrictions of initial and boundary conditions. Based on the general solution, we carried out the functional prediction using the nonlinear least squares method, and determined a rigorous solution for the time constant of the radical increase.
The counting efficiencies of two lung monitor systems—phoswich detector system and germanium detector system—were measured for lungs and liver loaded with241Am in the JAERI phantom. It was found that the germanium detector system for241Am loaded lungs counting gives the full-energy peak predominated by the absorption of the gamma-ray photon in a single photoelectric interaction and is less sensitive to241Am loaded liver. The241Am loaded lung activities could be reasonably estimated using germanium detector system rather than phoswich detector system.