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[en] Full text: Iodine is one of the important radionuclides those should be considered for an accidental radionuclide release from the nuclear facility. Even the radiological half life of iodine-131 is shorter than the others, its impact on the thyroid is crucial in the beginning stage of accidental release. European Community has conducted lots of experiments for iodine transfer from the air to plant or soil to plant, however it concerns mostly to the western foodstuffs. The Chinese cabbage that is one of the principal foodstuffs in northeastern countries is tested by iodine exposure. Iodine-125 of which radiological half life is 60 days was used to measure the concentration change. Experiments were carried out four times which have different exposure times. The iodine source was prepared by chemical reaction of NaI in order to avoid producing relatively large elemental iodine which might be generated by crystal evaporation. The deposition velocity was obtained from the integrated air concentration and surface concentration of Chinese cabbage. The biological half life implying the weathering effects was also calculated. (author)
[en] A very high efficiency liquid-liquid chromatography (LLC) system based on 5- and 20-μm diameter porous silica microspheres was used to effect radiochemical separations of metal ions that required very large decontamination factors and/or high speeds. The stationary phase was 25-30% (w/w) of di(2-ethylhexyl) orthophosphoric acid (HDEHP) in dodecane. Nitric acid was used as the mobile phase. The mass transfer coefficient term, C, was determined from height equivalent to a theoretical plate vs. interstitial linear velocity data for the elution of Ca2+ and compared with values calculated from the interfacial mass transfer coefficients measured in the corresponding liquid-liquid extraction system. The HDEHP high-efficiency LLC system was also investigated for possible use in enriching the naturally occurring isotopes of calcium. Isotopic exchange constants for 40Ca or 42Ca and 48Ca were measured chromatographically as a function of temperature. The enrichment of calcium isotopes was attempted on coupled columns at low flow velocities
[en] The α-decay half-lives for the even–even, even–odd, odd–even and odd–odd of 356 nuclei in the range have been studied within the analytical formula of Royer and also within the modified analytical formula of Royer. We calculated the new coefficient of the Royer by fitting 356 isotopes. Also, we considered the Denisov and Khudenko formula and obtained the new coefficient for the modified Denisov and Khudenko formula. We calculated the standard deviation and the average deviation. Analytical results are compared with the experimental data. The results are in better agreement with the experimental data when the effect of the isospin considered for the parent nuclei.