Department of Radioecology and Fukushima Project, National Institutes for Quantum and Radiological Sciences and Technology (QST), 4-9-1 Anagawa, Inage-ku, Chiba 263-8555 Japan.
Integrated Centre for Science and Humanities, Fukushima Medical University, 1 Hikarigaoka, Fukushima City, Fukushima 960-1295, Japan.
Radiat Prot Dosimetry. 2022 Sep 9;198(13-15):934-937. doi: 10.1093/rpd/ncac015.
The Fukushima soils have been collected from Namie and Futaba areas for the radiocaesium and uranium isotope ratio studies. The 137Cs activity concentration of soil samples ranged from 6 ± 1 to 756 ± 14 kBq/kg. The uranium isotope ratios are measured using multi collector inductively coupled plasma mass spectrometry. The activity ratio (234U/238U) of the Fukushima soils is calculated from the measured 234U/238U isotope ratio. Activity ratio varied from 0.98 to 1.02 which indicates that 234U and 238U are in secular equilibrium. The 235U/238U atomic ratio of the Fukushima soils did not show any heterogeneity compared with the natural terrestrial ratio even with high level of 137Cs in soils.
本研究从福岛县的女川和双叶地区采集了土壤样本，用于放射性铯和铀同位素比值研究。土壤样本中 137Cs 的活度浓度范围为 6 ± 1 到 756 ± 14 kBq/kg。铀同位素比值采用多接收电感耦合等离子体质谱法进行测量。福岛土壤的活度比（234U/238U）是通过测量的 234U/238U 同位素比值计算得出的。活度比在 0.98 到 1.02 之间变化，表明 234U 和 238U 处于长期平衡状态。与天然陆地比值相比，即使土壤中 137Cs 含量很高，福岛土壤的 235U/238U 原子比也没有表现出任何不均匀性。
