Photoradiation processes

Basic results of the investigations of the processes taking place during the combined action of ionizing radiation and light on substances are presented. They indicate new trend in the physical chemistry appeared on the verge of radiation and photochemistry. The results are presented which illustrate transformations induced by the light in radicals formed by ionizing radiation in various materials. The mechanism of these processes is characterized. Data are presented and discussed on general regularities and new effects difference in the results of the simultaneous and time-different action of both kinds of radiation and the phenomenon of ''photoradical chains'' involving into the chemical process a significant number of molecules of a substance which does not absorb the light directly due to photoconversion of primary vacant radicals. The mechanism of this phenomena is explained on the basis of EPR data on the character of vacant radicals transformation, and also taking into account the excitation of electrons by light stabilized in a solid substance. Data for different classes of materials are presented: organic and inorganic compounds, polymers. Some practical aspects of photoradiation prosesses are considered