气载流出物中碳-14对氚测量的干扰分析  

Analysis on the interference of carbon-14 on tritium monitoring in gaseous effluent

作　　者：保莉[1] 杨有坤 廉冰[1] 郭琛 马旭媛 杨海兰[1] BAO Li;YANG Youkun;LIAN Bing;GUO Chen;MA Xuyuan;YANG Hailan(China Institute for Radiation Protection Key Laboratory of Radiation Environment&Health of the Ministry of Ecology and Environment,Taiyuan 030006)

机构地区：[1]中国辐射防护研究院国家环境保护辐射环境与健康重点实验室,太原030006

出　　处：《辐射防护》2023年第S01期52-55,共4页Radiation Protection

摘　　要：氚是核设施气态流出物中重要的放射性核素,作为低能纯β核素,目前多采用累积取样、实验室分析的方式进行监测。气载流出物中的氚取样后未经纯化的制样测量,可能会存在其他核素干扰的问题。对气载流出物中的碳-14对氚的测量干扰进行定量分析,可为气载流出物中氚的准确测量提供参考。通过氚、碳-14取样特点分析确定取样阶段的干扰,制备并测量单核素和氚碳双标记样品,明确碳-14对氚测量阶段的干扰影响。取样阶段,碳-14在氚的水捕集液中的吸收量随温度变化而变化,在10℃时CO_(2)在300 mL氚捕集液中的溶解度为0.70 g。测量阶段,碳-14对氚的影响会因液闪谱仪的设计工作原理而异,如Quantulus1220型超低水平液闪谱仪,在氚测量模式下不能忽略碳-14的计数贡献;而LSA2000A型低水平液闪谱仪,在氚测量模式下可以不考虑碳-14的计数贡献。Tritium is an important radionuclide in gaseous emissions from nuclear facilities.As a low-energy pureβradionuclide,tritium is mostly monitored by cumulative sampling and laboratory analysis.After tritium is sampled in airborne effluent and measured without purification,there may be interference from other radionuclides.The interference of carbon-14 in airborne effluent on tritium measurement is quantitatively analyzed,which provides reference for accurate and quantitative monitoring of tritium in airborne effluent.According to the sampling characteristics of tritium and carbon-14,the interference in the sampling stage is determined,and the mono-nuclear and tritium-carbon double-labeled samples are prepared and measured to determine the interference effect of carbon-14 on tritium measurement stage.In the sampling stage,the influence of carbon-14 on tritium varies with the temperature,and the solubility of CO_(2) in tritium capture solution is 0.70 g at 10℃.In the measurement stage,the influence of carbon-14 on tritium will vary according to the design and working principle of liquid scintillation spectrometer.For example,if Quantulus1220 ultra-low level liquid scintillation spectrometer is used,the counting contribution of carbon-14 can not be ignored in tritium measurement mode;If LSA2000A liquid scintillation spectrometer is used,the counting contribution of carbon-14 can be ignored in tritium measurement mode.

关 键 词：氚 碳-14 干扰 液闪 

分 类 号：TL751[核科学技术—辐射防护及环境保护]