AlphaGUARD PQ2000测氡仪扩散模式下对^(220)Rn的响应研究  

Response of AlphaGUARD PQ2000 radon detector to ^(220)Rn in diffusion mode

作　　者：肖亚松 何正忠 王可欣 冯佳璐 吕丽丹 XIAO Yasong;HE Zhengzhong;WANG Kexin;FENG Jialu;LYU Lidan(School of Nuclear Science and Technology,University of South China,Hengyang 421001,China)

机构地区：[1]南华大学核科学技术学院氡湖南省重点实验室,衡阳421001

出　　处：《核技术》2024年第10期98-105,共8页Nuclear Techniques

基　　金：国家自然科学基金(No.12175102);湖南省自然科学基金(No.2022JJ40346)资助。

摘　　要：测量环境的^(222)Rn浓度时,如果存在高浓度^(220)Rn,将会对无法甄别^(222)Rn/^(220)Rn的测量仪器的测量结果产生干扰,有必要确定该类测量仪器对^(220)Rn的响应程度,以确保其^(222)Rn浓度测量结果的准确性。本文针对AlphaGUARD PQ2000测氡仪对^(220)Rn的响应系数随风速和风向的变化在标准^(220)Rn室中开展了实验研究,使用单闪烁室流气静态法测量^(220)Rn室中的^(220)Rn浓度,观察不同风速风向下AlphaGUARD PQ2000的^(222)Rn浓度示值来计算AlphaGUARD PQ2000对^(220)Rn的响应系数。研究结果表明:风速和风向的改变都会使得响应系数发生变化,风速从0.05 m·s^(-1)增大到3.50 m·s^(-1)时,AlphaGUARD PQ2000对^(220)Rn的响应系数从0.044增大到0.126;静态无风时响应系数为0.049;固定风速为0.71 m·s^(-1),风向与AlphaGUARD PQ2000扩散窗的角度从0°变化到180°时,响应系数从0.083减小到0.051;固定风速为1.43 m·s^(-1),风向与AlphaGUARD PQ2000扩散窗的角度从0°变化到180°时,响应系数从0.115减小到0.081。本研究得到的响应系数随风速风向的变化规律可为修正^(220)Rn对AlphaGUARD PQ2000测氡仪扩散模式下^(222)Rn的测量结果的干扰提供参考。[Background]222Rn/^(220)Rn and their daughters are widely present in the atmosphere and indoor environment.The presence of high-concentration ^(220)Rn can affect the accuracy of 222Rn concentration measurements.[Purpose]This study aims to measure radon concentration more accurately by investigating the variation in the response coefficients of the AlphaGUARD PQ2000 radon monitor to ^(220)Rn under thoron gas concentrations with different wind speeds and directions within a standard radon chamber.[Methods]The single-scintillation proportional counter flow gas static method was employed to determine the thoron concentration in this study.Firstly,a self-made and stable high emissivity solid ^(220)Rn source at the University of South China was applied to the generation of ^(220)Rn gas in the chamber,a temperature and humidity control system was adopted to regulate the inside temperature and humidity of ^(220)Rn whilst the wind speed was controlled by changing the operating frequency of the variable frequency fan.Then,the readings of the AlphaGUARD PQ2000 were observed at various wind speeds and directions under controlled temperature and humidity conditions.Subsequently,the response coefficients of the AlphaGUARD PQ2000 to thoron in diffusion mode were calculated according the observed results.[Results]When the wind speed increases from 0.05 m·s^(-1) to 3.50 m·s^(-1),the response coefficient of AlphaGUARD PQ2000 to ^(220)Rn increases from 0.044 to 0.126.When there is no wind,the response coefficient is 0.049.When the wind speed is fixed at 0.71 m·s^(-1) and the angle between the wind direction and AlphaGUARD PQ2000 diffusion window changes from 0°to 180°,the response coefficient decreases from 0.083 to 0.051.When the wind speed is fixed at 1.43 m·s^(-1) and the angle between the wind direction and AlphaGUARD PQ2000 diffusion window changed from 0°to 180°,the response coefficient is reduced from 0.115 to 0.081.[Conclusions]The response coefficients obtained in this study can provide a reference for correcting t

关 键 词：AlphaGUARD PQ2000 风速 风向 响应系数 ^(220)Rn 

分 类 号：TL811.1[核科学技术—核技术及应用]