Zhang Yingying, Li Changkai, Liu Dongyan, Zhang Ying, Liu Yan
Shandong Provincial Key Laboratory of Ocean Environment Monitoring Technology, Shandong Academy of Sciences Institute of Oceanographic Instrumentation, No. 28 Zhejiang Road, 266001 Qingdao, China.
China National Petroleum Corporation Logging Co., Ltd., No. 142 Weiyang Road, 710021 Xian, China.
Appl Radiat Isot. 2015 Apr;98:44-8. doi: 10.1016/j.apradiso.2015.01.009. Epub 2015 Jan 16.
To develop in situ NaI(Tl) detector for radioactivity measurement in the marine environment, the Monte Carlo N-Particle (MCNP) Transport Code was utilized to simulate the measurement of NaI(Tl) detector immersed in seawater, taking into account the material and geometry of the detector, and the interactions between the photons with the atoms of the seawater and the detector. The simulation results of the marine detection efficiency and distance were deduced and analyzed. In order to test their reliability, the field measurement was made at open sea and the experimental value of the marine detection efficiency was deduced and seems to be in good agreement with the simulated one. The minimum detectable activity for (137)Cs in the seawater of NaI(Tl) detector developed was determined mathematically at last. The simulation method and results in the paper can be used for the better design and quantitative calculation of in situ NaI(Tl) detector for radioactivity measurement in the marine environment, and also for some applications such as the installation on the marine monitoring platform and the quantitative analysis of radionuclides.
为开发用于海洋环境放射性测量的原位碘化钠（铊）探测器，利用蒙特卡罗N粒子（MCNP）输运代码模拟了浸入海水中的碘化钠（铊）探测器的测量情况，其中考虑了探测器的材料和几何形状，以及光子与海水和探测器原子之间的相互作用。推导并分析了海洋探测效率和距离的模拟结果。为测试其可靠性，在公海进行了现场测量，并推导了海洋探测效率的实验值，该实验值似乎与模拟值吻合良好。最后通过数学方法确定了所开发的碘化钠（铊）探测器在海水中对（137）铯的最小可探测活度。本文的模拟方法和结果可用于更好地设计用于海洋环境放射性测量的原位碘化钠（铊）探测器并进行定量计算，也可用于诸如安装在海洋监测平台以及放射性核素定量分析等一些应用。
