[The decomposition of the EPR spectra of multicomponent systems irradiated at 77 K into paramagnetic center signals of different natures].

Main principles of the way to decompose an EPR spectrum of a multicomponent system, irradiated at 77 K, into separate radiation-induced paramagnetic centre signals are given. The decomposition is possible due to the computer assistant spectra processing, and is based on different properties of different paramagnetic centres, namely, on different thermostability of the centres, on different rate of relaxation, and on different photosensitivity. Concrete examples of the EPR spectrum decomposition into different free radical signals are given for cases of murine liver and spleen irradiated at 77 K. Radiochemical yields of different free radicals, induced by gamma radiation at 77 K in whole biological tissues, were defined. The data on nature and properties of the paramagnetic centres induced by radiation in biological tissues are shortly reviewed.