Authors:M. Ebihara, H. Ozaki, F. Kato, and H. Nakahara
Chlorine, bromine and iodine (hereafter, halogens) were detemined for rock samples by radiochemical neutron activation analysis. The powdered samples and reference standards prepared from chemical reagents were simultaneously irradiated for 10 to 30 minutes with or without a cadmium filter in a TRIGA-II reactor at the Institute for Atomic Energy, Rikkyo University. The samples were subjected to radiochemical procedures of halogens immediately after the irradiation. Iodine was firstly precipitated as PdI2, and chlorine and bromine were successively precipitated as Ag-halides at the same time. In this study, geological standard rocks, sedimentary rocks and meteorites were analyzed for trace halogens. In some Antarctic meteorites, iodine contents were observed to be anomalously high. Chlorine contents also are somewhat high. The overabundance of iodine and chlorine must be caused by terrestrial contamination on the Antarctica.
Authors:H. Terada, H. Shibata, F. Kato, and H. Sugiyama
To study the mechanism of accumulation of radiocesium by the mushroom (Pleurotus ostreatus (Fr.) Kummer Y-1), uptake of137 Cs and Cs in the presence of the alkali elements was investigated. The concentration ratio (concentration in the mycelia
or the fruit body (dry)/concentration in the medium (wet); CR) of137Cs was almost identical with that of Cs. The CR of137Cs decreased with increasing of Cs, K or Rb concentration in the media. Similarly, the CR of K decreased with increasing the
Cs concentration in the media. The result of137Cs gel filtration chromatography of the mycelia cultivated in the media containing Cs showed that137Cs was not bound to molecules with more than 10000 molecular weight.