caa a22 4500 465730337 CHVBK 20180323111739.0 cr unu---uuuuu 170327e19900201xx s 000 0 eng 10.1007/BF02039845 doi (NATIONALLICENCE)springer-10.1007/BF02039845 Selective determination of extremely low-levels of the thorium series in environmental samples by a new delayed coincidence method [Elektronische Daten] [T. Hashimoto, Y. Sakai] An attempt was made to apply a delayed coincidence method for the absolute determination of trace quantities of the thorium series. This method is based on selective counting of the relatively short lived nuclide216Po (half-life 145 ms) in the thorium series members. For this purpose, a "list mode” time analyzing system combined with a liquid scintillation counter was assembled by means of a conventional microcomputer. A multiple time analysis was employed in the processing and data compilation of delayed coincidences to distinguish them from the true coincidences due to random events. From a time spectrum, the decay component of216Po (145 ms) can be selectively measured. Absolute activities of its progenitors,224Ra and228Th as well as220Rn, can be determined even in the presence of the background radiations of the almost equivalent activity-strength of concomitant uranium series. Akadémiai Kiadó, 1990 Hashimoto T. Department of Chemistry, Faculty of Science, Niigata University, 950-21, Niigata, Japan aut Sakai Y. Department of Chemistry, Faculty of Science, Niigata University, 950-21, Niigata, Japan aut Journal of Radioanalytical and Nuclear Chemistry Kluwer Academic Publishers 138/2(1990-02-01), 195-206 0236-5731 138:2<195 1990 138 10967 https://doi.org/10.1007/BF02039845 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/BF02039845 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Hashimoto T. Department of Chemistry, Faculty of Science, Niigata University, 950-21, Niigata, Japan aut NATIONALLICENCE 700 1- Sakai Y. Department of Chemistry, Faculty of Science, Niigata University, 950-21, Niigata, Japan aut NATIONALLICENCE 773 0- Journal of Radioanalytical and Nuclear Chemistry Kluwer Academic Publishers 138/2(1990-02-01), 195-206 0236-5731 138:2<195 1990 138 10967 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer