Geochemical behavior and activity ratios of Fukushima-derived radionuclides in aerosols at the Geological Survey of Japan, Tsukuba, Japan

摘要

Aerosols from the Fukushima Dai-ichi Nuclear Power Plant accident were collected at the Geological Survey of Japan. The temporal patterns of the Cs-134/Cs-137, Cs-136/Cs-137, and Te-132/Cs-137 activity ratios were consistent with expectations based on their half-lives. Those for I-131 and Te-129m decreased with some fluctuations. Ag-110m/Cs-137 declined more rapidly than expected and Nb-95/Cs-137 increased with time. The results suggest that the temporal patterns depended not only on their half-lives but also on many factors such as chemical speciation, the diversity of sources, changes in the temperature and discharge rate from the reactors, and the processes of transport.