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[en] Complete text of publication follows. A trap-and-atomizer device based on multiatomizer has been described recently. This compact and universal device enables to preconcentrate As, Sb, Bi and Se hydrides on-line prior their AAS detection. In this work, 125Sb and 205,206Bi radioactive indicators were used to (1) quantify the efficiency of the individual steps of preconcentration procedure and (2) to investigate the spatial distribution of the analytes in a quartz trap. Trapping efficiency of Sb was better than 92% (RSD6%) between 200 and 900 deg C. Trapping efficiency of Bi was above 96%(RSD5%) between 100 and 800 deg C whereas it has fallen to 83% at 900 deg C. Autoradiography showed that the area of the trapping spot increased with increasing trapping temperature. The trap is capable to trap up to 400 ng of Bi and 2ng of Sb, respectively. Typically, 1-10 ng of analyte is preconcentrated in ultratrace analysis. Also the volatilization step was proved to be efficient - only (1.81.6)% and (2.90.9)% of original Bi and Sb activity, respectively, was found in the traps after the volatilization. Results from our recent radiotracer study will be compared to those obtained previously with AAS detection. Potential of hydride trapping in quartz atomizers will be discussed. Financial supports from the Grant Agency of the ASCR (Project No. A400310507), Institute of Analytical Chemistry AS CR (Project No. AV0Z40310501) and the Grant Agency of Charles University (Project No. GAUK 306/2006/B-CH/PrF) are highly acknowledged.
[en] In a series of 48Ti bombardments of 144Sm the decay energy of the 189Bim (πs1/2) α transition that proceeds to the (πs1/2) ground state of 185Tl was measured to be 7.30(4) MeV. This result establishes the excitation energy of 189Bim as 190(40) keV rather than the adopted 92(10)-keV value. Our data indicate a leveling off in excitation energy at N∼106 for the s1/2 intruder state in the odd-A Bi isotopes rather than a continued drop at that neutron number as inferred by Coenen et al. in their discussion of intruder state systematics in the Pb region. Consequences of this discrepancy for the adopted excitation energy of the πs1/2 isomer in 187Bi are discussed
[en] We intend to study the half-lives of Bismuth isotopes via the alpha decay process. To go through the problem, we consider a potential model in which an angle-dependence is considered. Our results reveal that taking into account the multipole approximations for both parent and daughter nuclei will improve the results. (author)
[en] The modified two-potential approach (MTPA) is employed to study the exotic α-decay near the closed shells Z=82 and N=82, 126 within a deformed version of the cluster model. We perform systematic calculations on favored α-decay half-lives from both the ground states (g.s.) and the isomeric states (i.s.) by using the microscopic double-folding potential. The obtained α-decay half-lives are found to be in good agreement with the experimental data. This indicates that four types of α transitions among ground states and isomeric states (g.s. → g.s., g.s. → i.s., i.s. → g.s., i.s. → i.s.) are well described in a unified model. In addition, the unfavored α transitions in the Bi isotopes are investigated to pursue a further understanding of α-decay properties.
[en] The α-decay half-lives of 443 nuclei are investigated within the cluster model (CM). The results are compared with the experimental data. The coincidence between theoretical results and the experimental data are satisfied, implying the CM works quite well for the study on α-decay properties. Then the α-decay half-lives of Bi isotopes are calculated. The results are consistent with the known experimental data. The α-decay half-lives of the Bi isotopes without experimental data are predicted, which is useful for the future experimental detection and identification of these nuclei. (authors)