[en] A method is presented utilizing Ge(Li) spectrometric techniques for ⁴⁰K, and ⁴⁰Ar activity measurements characteristic of radioactive decay schemes in geological samples. The method is applicable for investigating samples of various densities. The results of experiments on the effect of density, radioactivity and geochemical features of samples (coal, bauxite, phosphates) and of radon diffusion are presented. (author) 8 refs.; 10 figs.; 3 tabs

[en] The kinetics and mechanism of cobalt sorption onto surfaces of plastic foil, gold and austenitic stainless steel type 08H18N10T used as construction material in WWER type nuclear reactors, were studied in order to obtain information about their contamination and decontamination behaviour. The sorption equilibrium, the potential and pH dependence of the accumulation were investigated using radiotracer technique based on the measurement of the β-radiation of ⁶⁰Co nuclides. It was found that both the character and extent of the sorption depend on the nature of the hydrolytic products of cobalt (Co²⁺, Co(OH)⁺, Co(OH)₂, etc.) and on the quality and pretreatment of the adsorbent. (author) 14 refs.; 13 figs