瓶装氮气中22组分挥发性卤代烃混合气体标准物质的研制

Development of a cylinder gas reference material containing 22 components volatile halogenated hydrocarbons in nitrogen

介绍瓶装1μmol/mol氮气中22组分挥发性卤代烃混合气体标准物质的研制过程。以22种挥发性卤代烃高纯试剂为原料,采用称量法制备并计算定值,评定制备过程引入的不确定度、以及均匀性和稳定性引入的不确定度,并将研制的标准物质送至中国计量科学研究院进行测试比对,采用En值评定比对结果,结果显示En值均<1,所有组分比对结果判定均为满意,验证研制标物定值结果的准确性。该气体标准物质获得国家二级气体标准物质证书,编号为GBW(E)062232,其定值的相对扩展不确定度为U=5.0%(k=2),有效期限为12个月。

This paper introduces the development process of a cylinder gas reference material containing 22 components volatile halogenated hydrocarbons at 1 μmol/mol in nitrogen. Source materials were obtained from commercial suppliers at very high purity.Gravimetric method was used to prepare the mixture and calculated the concentration value. The finally estimated uncertainty was combined by preparation process,homogeneity and stability. The validation result from NIM showed a satisfied consistency of all the compounds and a reliable accuracy of calculated concentration value,as En values were applied to evaluate the comparison result and all the En values were lower than 1. This gas reference material has acquired the certificate of national secondary gas reference material GBW （E） 062232,and the relative expanded uncertainty is 5.0%（k=2）with one year shelf life.