核辐射探测实验中核辐射场模拟与安全研究  

Study on Nuclear Radiation Field Simulation and Safety in Nuclear Radiation Detection Experiments

作　　者：熊铁军 钟丁生[1] 蔡小杰 张艳丽[1] 郦文忠[1] Xiong Tiejun;Zhong Dingsheng;Cai Xiaojie;Zhang Yanli;Li Wenzhong(The Engineering&Technical College of Chengdu University of Technology,Leshan 614007,China;Southwest University of Science and Technology,Mianyang 621010,China)

机构地区：[1]成都理工大学工程技术学院,乐山614007 [2]西南科技大学,绵阳621010

出　　处：《核安全》2020年第2期18-22,共5页Nuclear Safety

基　　金：乐山市科技局科研项目,项目编号:18JZD058。

摘　　要：本文在核辐射探测实验过程中,通过对核辐射探测实验室的辐射场进行模拟和研究,找到减轻核辐射对师生产生危害的办法。通过MCNP5软件进行实验室模型的建立、60Co空间模拟与理论值的对比、对屏蔽材料的类型及其组合方式进行模拟,找出适合的屏蔽材料组合,分析实验中放射源的辐射场剂量率及屏蔽效果。辐射剂量率随着远离放射源而逐渐减弱,在辐照时间相同的情况下,实验室两侧学生受到的辐射剂量是比较大的;单层屏蔽材料的模拟中,Pb的屏蔽效果远远好于SiO2;在3种屏蔽材料组合中,SiO2-Pb-Fe或SiO2-Fe-Pb多层屏蔽材料组合效果较好。在实验中,应尽量采用低能的放射源,增设和使用Pb或SiO2-Fe-Pb组合的屏蔽层,缩短受辐射照射时间,以降低对师生的核辐射照射伤害。In the process of radiation detection experiments, through the simulation and research of the radiation field in the nuclear radiation detection laboratory, the method to reduce the harm of nuclear radiation to teachers and students was found. MCNP5 software was used to establish the laboratory model, compare the spatial simulation of 60 Co with the theoretical value, simulate the types of shielding materials and their combinations, find out the appropriate shielding material combinations, and analyze the radiation field dose rate and shielding effect of the radioactive sources in the experiment. The radiation dose rate gradually decreases with the distance from the radiation source. Under the same irradiation time, the radiation dose received by students on both sides of the laboratory is relatively large. In the simulation of single layer shielding material, the shielding effect of Pb is far better than that of SiO2. Among the three kinds of shielding material combinations, the SiO2-Pb-Fe or SiO2-Fe-Pb multilayer shielding material combinations are better. In the experiment, low energy radiation source should be adopted as far as possible, and Pb or SiO2-Fe-Pb combination shielding layer should be added and used to shorten the radiation exposure time, so as to reduce the radiation exposure damage to teachers and students.

关 键 词：核辐射场 蒙特卡罗模拟 空间分布 放射源 

分 类 号：TL77[核科学技术—辐射防护及环境保护]