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Abstract  

186Re and 188Re, two strong beta- and weak gamma-emitters having short half-lives, are intensely studied as promising radionuclides for radiotherapy. Their use for biomolecule labeling is mainly due to their similar behavior with 99mTc. This paper presents the irradiation operations in a 14 MW Triga SSR Reactor, the chemical processing for obtaining a perrhenate solution of high activity and the final characterization of the products.

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Abstract  

The ion-exchange equilibrium of cesium and strontium ions on clinoptilolites from different deposits — Dzegvi and Tedzami /Georgian SSR/, Beli Plast and Beli Bair /Bulgaria/ in different cationic forms of the sorbents /natural, sodium, calcium and ammonium/ is studied. The static ion-exchange capacities are determined. The sorption isotherms are plotted and the corresponding distribution coefficients are calculated. Mechanical characteristics which are important for the assessment of the technological use of the sorbents in dynamic conditions are determined. The clinoptilolite from Beli Plast deposit has the highest capacity in comparison with the other studied zeolites. The selectivity of the clinoptilolites from Bulgarian deposits is independent of the cationic form of the sorbent while the selectivity of the Georgian clinoptilolites strongly depends on the cationic form; the selectivity of the ammonium form of Tedzami sorbent is the highest.

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Abstract  

The applicability of instrumental activation analysis by the conversion radiation of impurities in matrices with high specific gamma-activity has been studied. An iron-free toroidal magnetic β-spectrometer with 2 per cent resolution and 20 per cent transmission for 4 was used for measurement. The spectrometer was made at the Activation Analysis Laboratory of the Academy of Sciences of the Kazakh SSR. Comparative gamma- and beta-spectra of samples of amorphous selenium thin films with palladium, cadmium, indium and mercury impurities were obtained. It was established that the analysis by the spectra of internal conversion electrons enables to increase the detection sensitivity of these elements in selenium as compared to the gamma-spectrometric method. The procedure of mercury determination in amorphous selenium films was developed and by this method the investigation of the dependence of photoconductive properties of the film upon the total mercury content and its distribution on the film surface was carried out.

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.1, 0.3, 0.5 and 0.7) were synthesized by two different methods, i.e. solid state reaction (SSR) and suspension mixing of materials (SMM). As the initial compounds for preparation of the sample by ceramic method were used CeO 2 (ML-Chemica, Troubsko, CZ

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.fluid.2005.05.012 . 12. Oswal , SL , Putta , SSR 2001 Excess molar volumes of binary mixtures of alkanols with ethyl acetate from 298.15 to 323.15 K . Thermochim Acta 373 : 141 – 152 10

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the corresponding change of Eqs. 15 – 16 : (18) (19) The set of values of rate constants calculated for the two chosen reaction models are shown in Table 3 . The value “opt” refers to the minimal value of SSR. The values of “min” and “max

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