摘要
环境中气载放射性碘监测仪参考响应的测量标准为131I放射性参考源,以滤网、活性炭滤纸和活性炭滤盒集成组成的放射性碘采集器为源载体,采用Na131I放射性溶液与硫酸铁反应产生气态碘,并模拟环境采样流速采集气载131I;采用实验方法标定高纯锗?谱仪对以放射性碘采集器为源载体的131I放射源的探测效率,据此测定131I放射性参考源的活度,作为现场校准用的测量标准。初步的实验结果表明,气载碘放射性监测仪参考响应的校准是可行的。
Background： Environment gaseous radioactive iodine monitoring is important for nuclear power plant safety. 131Ⅰ reference source is used as the measurement standard of reference response for environment gaseous radioactive iodine monitoring equipment, which uses glass fibrous filter, active carbon filter and impregnated activated carbon filter cartridge as carriers. Purpose： It is essential to calibrate the reference response for gaseous radioactive iodine monitoring equipment to ensure accurate gaseous radioactive iodine monitoring. Methods： Gaseous radioactive iodine was produced from Na131Ⅰ solution with ferric sulfate through redox reaction, and collected under environment sampling condition for preparing the 131Ⅰ reference source. The detection efficiency of high-purity germanium gamma spectrometer for 131Ⅰ in collection device was determined. Therefore, the 131Ⅰ reference source was prepared and quantified as a reference standard for field calibration. Results： The experimental results show that the activity of the 131Ⅰ reference source will be about 10 kBq while the 1 MBq Na131Ⅰ solution is prepared to get it, the radioactivity value could be adjusted by regulating the activity of the Na131Ⅰ solution. The detection efficiency of gamma spectrometer for 131Ⅰ reference source ranged from 4.90% to 6.82%, while the distribution parameter changed from 0.09 mm-1 to 0.34 mm-1. Conclusion： The preliminary experiment shows good practicability of proposed method for the calibration of reference response for gaseous radioactive iodine monitoring equipment.
出处
《核技术》
CAS
CSCD
北大核心
2015年第5期34-37,共4页
Nuclear Techniques
基金
质检公益性行业科研专项(No.201210044)
上海市科委科研计划(No.12DZ2293802)资助
关键词
气载放射性碘
参考响应
碘采集器
测量标准
Gaseous radioactive iodine
Reference response
Iodine collection device
Measurement standard
作者简介
唐方东，男，1964年出生，1985年毕业于复旦大学放射化学专业，教授级高工，主要从事放射性计量学研究工作
