摘要现阶段由于化工厂生产原料含有一定量的放射性核素,而且化工厂污染物排放量巨大,导致其周边有不少受到放射性核素污染的土壤,本论文旨在研究电池电镀等化工厂周边土壤中放射性核素的种类与分布关系。通过在高纯锗半导体探测器中进行测量来确定核素种类和含量,并计算得出比活度和富集因子。通过把不同离厂距离处的比活度数值连接成为比活度的拟合曲线可以发现,232Th、214Bi、214Pb、212Pb 这四种核素随着与污染源距离的增加,比活度呈近似线性的下降,说明相应放射性核素的浓度随着与厂址的距离的增大而降低。40K 则与污染源的距离并无太大关系,随机性较强。距离考察厂址 100米范围内采集的土壤样品中的 214Bi、214Pb、212Pb核素的富集因子均大于 1.5,说明这些土壤样品中的相应放射性核素均较对应厂家的生产原料中核素浓度有不同程度的富集。本论文对土壤中放射性核素的种类和富集情况进行了详细的分析,对相关研究有很好的参考意义。42437
毕业论文关键词 土壤污染 化工污染 放射性核素 比活度 富集因子
Title The Types And Distribution Relationship Of The Radionuclide In The Soil Around The Battery and Galvanization Plant
Abstract At this stage, the raw materials of the chemical production contain radioactive nuclide, and the chemical production has a large pollutant emissions. Consequently, there is a lot of radionuclide contaminated soil surrounding the chemical plant. This article studies the types and distribution relationship of radioactive nuclides in chemical plant surrounding soil. In this research, we collected soil samples and put them in the high purity germanium semiconductor detector to measure the types and levels of the nuclides. We connect the value of specific activity of different distance from the plant and make a fitting curve of the specific activity, we found that the specific activity of 232Th, 214Bi, 214Pb, 212Pb decreased with the increasing distance from the plant. The specific activity form an approximate linear decline, it indicates the concentration of the radioactive nuclide decreased with the increase of the distance from the plant. The relation between the specific activity of 40K and the distance from plant is not big, it has a strong randomness. The enrichment factor of the 214Bi, 214Pb, 212Pb are basically bigger than 1.5 in every samples within 100 metres from the plant. Consequently, the soil that surrounding the factory has radioactive nuclide concentration and the concentration reduce near to linear with the increasing distance. This paper analyzes the types and enrichment condition of the radionuclide in soil detailedly, it has a good reference for related research.
Keywords soil pollution chemical industrial pollution radionuclides specific activity enrichment factor
目次
1绪论1
1.1课题研究背景1
1.2国内外相关课题的研究进展2
2实验部分6
2.1土壤样品的采集和处理6
2.1.1采样6
2.1.2采样点的布设6
2.1.3研究区域概况7
2.1.4样品处理7
2.2土壤样品的γ能谱测量与数据分析7
2.2.1实验所关注的核素8
2.2.2测量步骤8
2.2.3比活度和富集因子计算方法和公式8
3结果与讨论10
3.1璞瑞电池厂周围土壤放射性核素的测量分析10
3.2双登电池厂周围土壤放射性核素的测量分析11
3.3泰通电镀厂周围土壤放射性核素的测量分析13
3.4各放射性核素富集因子15
结论18
致谢19
参考文献20 电池电镀化工厂周边土壤中放射性核素的种类与分布关系:http://www.youerw.com/huaxue/lunwen_42868.html