土壤中钚的迁移行为研究

辐射防护 ›› 2017, Vol. 37 ›› Issue (1): 1-7.

土壤中钚的迁移行为研究

倪有意¹, 卜文庭¹, 郭秋菊¹, 董微¹, 杨斌², 全葳², 孟瑞杰²

1.北京大学物理学院核物理与核技术国家重点实验室,北京 100871;
2.环境保护部核与辐射安全中心,北京 100082

收稿日期:2016-03-07 出版日期:2017-01-20 发布日期:2021-11-11
通讯作者: 郭秋菊。E-mail:qjguo@pku.edu.cn
作者简介:倪有意(1992—),男,2014年毕业于北京大学物理学院物理专业,现为北京大学物理学院辐射防护与环境保护专业博士研究生。E-mail:niyouyi@pku.edu.cn
基金资助:
国家自然科学基金资助项目(No.11275015)。

Study on the migration of Pu in soil

Ni Youyi¹, Bu Wenting¹, Dong Wei¹, Guo Qiuju¹, Yang Bin², Quan Wei², Meng Ruijie²

1. National Key Laboratory of Nuclear Physics and Technology, School of Physics, Peking University, Beijing 100871;
2. Nuclear and Radiation Safety Center,MEP, Beijing 100082

Received:2016-03-07 Online:2017-01-20 Published:2021-11-11

摘要/Abstract

摘要： 我国表层土壤中存在的钚主要来自于20世纪中后叶大气层核试验之后的全球沉降。本研究以土壤中现存的钚为研究对象,利用加速器质谱(AMS)和电感耦合等离子体质谱(ICP-MS)对环境中痕量水平钚同位素精准测量技术,在我国部分典型地区进行了现场土壤纵向分层采样和实验室测量。在此基础之上,将对流-弥散方程在单次瞬时输入情况下的解与我国不同地区土壤柱中钚核素的垂直分布数据进行了拟合,得到新疆、湖北、贵州、重庆、甘肃土壤中钚核素的表观对流系数为0.046～0.163 cm/a,表观扩散系数为0.058～0.339 cm²/a,土壤中^239+240Pu浓度峰的迁移速率为0.063~0.187 cm/a。实测结果表明,钚同位素在土壤中的迁移速率与土壤有机质含量有明确的负相关关系。

关键词: Pu, 核素迁移, AMS, ICP-MS, 对流-弥散模型

Abstract: The ultra-trace level of Pu (plutonium) isotopes in Chinese surface soil are mainly resulted from global fallout following the world-wide atmospheric nuclear tests last century. The vertical migration behaviors of Pu in soil were studied by field sampling and laboratory measurements using AMS (Accelerator Mass Spectrometry) and ICP-MS (Inductively Coupled Plasma Mass Spectrometry). Subsequently by fitting the vertical distribution of ^239+240Pu with the solution of convection-dispersion equation in single pulse condition, the apparent convection coefficient V in Chinese soils was found to be 0.046—0.163 cm/a, the apparent diffusion coefficient D ranged from 0.058 to 0.339 cm²/a and the migration velocity of ^239+240Pu concentration peak in soils of different areas from 0.063 to 0.187 cm/a. Based on these, the predicted ^239+240Pu concentration peak would remain in top 10 cm of the surface soil in Chongqing province after 200 years' migration. The results indicated that the organic matter content of soil would be a key factor influencing the migration behavior of Pu. Besides, other soil parameters such as porosity, soil particle size, cation exchange capacity etc. tend to have influences on the migration velocity of Pu in soils.

Key words: Pu, radionuclides migration, AMS, ICP-MS, convection-dispersion equation

中图分类号:

X837

倪有意, 卜文庭, 郭秋菊, 董微, 杨斌, 全葳, 孟瑞杰. 土壤中钚的迁移行为研究[J]. 辐射防护, 2017, 37(1): 1-7.

Ni Youyi, Bu Wenting, Dong Wei, Guo Qiuju, Yang Bin, Quan Wei, Meng Ruijie. Study on the migration of Pu in soil[J]. RADIATION PROTECTION, 2017, 37(1): 1-7.

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