核化学与放射化学2025，Vol.47Issue(3)：259-266,8.DOI:10.7538/hhx.2025.47.03.0259
一种针对90Y的淬灭指数及其在90Sr分析中的新应用
A Quench Index for 90Y and Its New Applications in 90Sr Analysis
冯孝贵 1袁建华 1何千舸 1靳小军 2孔雪艳 2王建晨 1陈靖1
作者信息
- 1. 清华大学核能与新能源技术研究院,北京 100084
- 2. 中核四0四有限公司第二分公司,甘肃兰州 732850
- 折叠
摘要
Abstract
Based on the customized quench index qx for 90Y and the modified 2-window approach,a simple method has been developed to analyze 90Sr using a liquid scintillation spectrometer,sometimes supplemented by γ spectrometer.The liquid scintillation counting(LSC)spectrum of 90Y exhibits good linearity in the high-energy part,on the basis of which qx is defined.The key point of the modified 2-window approach is to obtain the ratio of the count rates of two windows(also known as region of interest,or ROI),CRH/CRw,where CRw is the count rate in ROIw,i.e.the whole region of interest(usually taken as channels 1-1 024);CRH is the count rate in ROIH,i.e.the high-energy region of interest.The right endpoint of ROIH is usually fixed at channel 1024,and the left endpoint varies with the quenching level of the sample.This paper provides a method to select the left endpoint of ROIH and to keep the value of CRH/CRW about 0.277 9,with the relative standard deviation of 0.84％.There are two prerequisites for using this method:(1)the quenching level of the sample is relatively low,in order that the counting efficiency of 90Sr or 90Y can be approximately considered as 100％in ROIW;(2)there is no interference from other nuclides than 90Y in ROIH.Three types of real samples from the hot test of high-level radioactive waste separation have been analyzed to show the specific steps of using this method.Because of the radioactive equilibrium of 90Sr/90Y in these samples,three ways of calculating the count rate of 90Sr have been adopted to verify each other.The first one is to obtain the count rate of 90Sr by subtracting the count rate of 90Y from the total count rate of 90Sr/90Y.The second one is just to let the count rate of 90Sr be equal to the count rate of 90Y.The third one is to divide the total count rate of 90Sr/90Y by 2 to obtain the count rate of 90Sr.The results indicate that the count rate of 90Sr obtained by this method is accurate and reliable.This method only requires linear fitting of the high-energy part of the LSC spectra.The method is simple and easy to use.With the application suggestions,users can choose appropriate analysis strategies according to the characteristics and analysis requirements of the sample.For analyzing 90Sr in samples of 90Sr/90Y with or without 137Cs,neither chemical separation nor waiting for the radioactive equilibrium of 90Sr/90Y is required,if the count rate of 90Sr is not too low.关键词
液闪/淬灭指数/改进双窗法/线性拟合/90Sr/90YKey words
LSC/quench index/modified 2-window approach/linear fitting/90Sr/90Y分类
化学引用本文复制引用
冯孝贵,袁建华,何千舸,靳小军,孔雪艳,王建晨,陈靖..一种针对90Y的淬灭指数及其在90Sr分析中的新应用[J].核化学与放射化学,2025,47(3):259-266,8.
