The role of induced secondary radiation in in situ sorption studies using β-, γ-emitting radionuclides

The effect of γ-induced radiation in in situ sorption measurements of 60Co (emitting β- and γ-radiation) is described. The results presented show that the intensity of solution background is primarily due to the γ-induced radiation (possibly caused by photoeffect and Compton-scattering) and does not change during cobalt accumulation. Experiments were carried out with a pure β-emitting isotope (99Tc) in order to elaborate a method for the separation of the intensities originating from β- and γ-induced radiations. Various methods of evaluation of sorption measurements are discussed. The extension of the method to application of different radioactive nuclides is considered. (author) 5 refs.; 8 figs.; 2 tabs