Parajuli Durga, Takahashi Akira, Tanaka Hisashi, Sato Mutsuto, Fukuda Shigeharu, Kamimura Ryuichi, Kawamoto Tohru
Nanosystem Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), 1-1-1 Higashi, Tsukuba, 305-8565, Japan.
Nanosystem Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), 1-1-1 Higashi, Tsukuba, 305-8565, Japan.
J Environ Radioact. 2015 Feb;140:78-83. doi: 10.1016/j.jenvrad.2014.11.005. Epub 2014 Nov 25.
Cesium extraction behavior of brown forest type soil collected from paddy fields in Fukushima nuclear accident affected areas was studied. In nitric acid or sulfuric acid solutions at elevated temperature, the concentration of Cs in soil available for extraction, m0, has been estimated on the basis of modified canonical equation and the equations derived from assumed equilibria. With the variation in temperature, mixing time, and soil to solvent ratio, the observed m0 values in 0.5 M acid solution ranged between 1.5 and 2.9 mg cesium per kilogram of soil. By increasing the acid concentration to 3 M, the value of m0 could be sharply increased to 5.1 mg/kg even at 95 °C. This variation in the extractable concentration of cesium with the parameters signifies the existence of different binding sites in the soil matrix. The results observed for uncontaminated sample could be reproduced with the radioactive cesium contaminated sample belonging to the same soil group.
对从福岛核事故影响地区稻田采集的棕色森林土型土壤的铯提取行为进行了研究。在高温的硝酸或硫酸溶液中，基于修正的正则方程和从假定平衡推导的方程，估算了可供提取的土壤中铯的浓度m0。随着温度、混合时间和土-溶剂比的变化，在0.5M酸溶液中观察到的m0值范围为每千克土壤1.5至2.9毫克铯。通过将酸浓度提高到3M，即使在95°C时，m0值也可急剧增加到5.1mg/kg。铯可提取浓度随这些参数的变化表明土壤基质中存在不同的结合位点。未受污染样品的观察结果可与属于同一土壤组的放射性铯污染样品重现。
