摘要
建立了直流辉光放电质谱法(DC-GDMS)测定核级石墨粉中痕量杂质元素的方法。用一定的压力将石墨粉镶嵌在高纯铟片上,形成一个直径约为5 mm的圆形石墨薄层,用铟片辅助石墨粉放电,实现了粉状样品直接检测。优化的实验条件为放电电流0.8 mA,放电电压1.2 kV,放电气体流速0.437 mL/min。用石墨粉标准样品(19J T61029)单点校准了仪器相对灵敏度因子,消除基体效应,实现15个关键杂质元素定量分析。方法检出限为5.0 ng/g,在单侧0.05显著性水平下,利用Student's t检验,方法测定结果t值均小于临界值,与标准值无显著性差异。相对标准偏差(RSD)均小于10%。本方法与电感耦合等离子体光谱法测定结果比较,相对误差在2.4%~17.4%之间。
A method for the determination of trace impurity elements in nuclear grade graphite powder by direct current glow discharge mass spectrometry was developed.The graphite powder was inlaid on the high purity indium chip with suitable pressure to form a circular graphite thin layer with a diameter of about 5 mm.Under the optimized conditions,the indium chip was used to assist the discharge of the graphite powder,achieving the direct analysis of the powder sample.The current voltage and gas flow rate of the discharge were 0.8 A,1.2 kV and 0.437 mL/min,respectively.The relative rensitivity factor(RSF)was calibrated by a single point to eliminate the matrix effect using graphite powder standard sample(19 J T61029)and the quantitative analysis of15 key impurity elements were attained.The detection limit was 5.0 ng/g.At the one side 0.05 significance level,Students’s t test was used and the t value was less than the critical.There was no significant difference with the standard value.The relative standard deviations(RSDs)were less than 10%except for some elements of low content.The established method was applied to the determination of unknown samples,and the relative error was between 2.4%and 17.4%,in good agreement with that of inductively coupled plasma method.
作者
刘红
陈晓彤
徐刚
刘英
孙海峰
贺林峰
杨复光
张英新
LIU Hong;CHEN Xiaotong;XU Gang;LIU Ying;SUN Haifeng;HE Linfeng;YANG Fuguang;ZHANG Yingxin(Guobiao(Beijing)Testing&Certification Co.,Ltd,Beijing 100088;Institute of Nuclear and New Energy Technology,Tsinghua University,Beijing 100084;China United Test&Certification Co.,Ltd,Beijing 100088)
出处
《分析试验室》
CAS
CSCD
北大核心
2021年第2期135-139,共5页
Chinese Journal of Analysis Laboratory
基金
国家科技重大专项(ZX06901)
清华大学自主科研计划项目资助。
关键词
痕量杂质
辉光放电质谱法
核级石墨
trace impurities
glow discharge mass spectrometry
nuclear grade graphite
