ABSTRACT
Ionizing radiation is used in material processing (Chmielewski 2006b, 2007), sterilization (IAEA 2008), food irradiation (Chmielewski and Migdal 2005), and environmental protection (Chmielewski 2011). Two sources of radiation are widely used: gamma irradiators (Chmielewski 2005) and electron accelerators (IAEA 2005). Both kinds of radiation are so-called ionizing radiation, since due to the energy of the photons or electrons, transfer of radiation leads to the formation of secondary electrons, which creates ions, free radicals, and other reactive species in matter. Then, chemical processes take place in the irradiated material, the intensity of which depends on the dose of energy absorbed, the dose rate, and other factors (Chmielewski 2006a). Regarding gamma sources, those using 60Co are most common. An image of the laboratory type of gamma cell is presented in Figure 20.1. This kind of equipment is suitable for tests on nanostructure formation.
