气相质谱仪校准用氮气中4组分混合气体标准物质的研制

The development of gas chromatography-mass spectrometry calibration for 4 components in nitrogen mixture gas reference material

介绍0.1μmol/mol气相质谱仪校准用氮气中4组分混合气体标准物质的研制方法。标准气体的组分为溴氯甲烷、1,4-二氟苯、氯苯-D5和4-溴氟苯,所采用的制备及分析方法分别为注射称量法和GC-MS法。通过瓶内压力及各组分浓度随时间的变化考察其浓度的均匀性和稳定性。对标准气体的制备过程及均匀性和稳定性引入的不确定度进行评定。实验结果表明,4组分混合气体标准物质在0.5～10 MPa范围内具有较好的压力均匀性和稳定性,其相对扩展不确定度为5.0%(k=2),使用有效期为1年。

The development method of gas chromatography-mass spectrometry calibration of 4 components that containing bromochloromethane,1,4-difluorobenzene,chlorobenzene-D5 and 4-bromofluorobenzene at 0.1μmol/mol in nitrogen gas reference material is described The gas standard is prepared by gravimetric preparation method and is intercompared to the existing gas cylinder standard using gas chromatography with a mass spectrometry detector.Relationships between time or pressure and homogeneity or stability were also investigated.The paper also evaluated the uncertainties from preparation using gravimetric method,uniformity and stability.All the research results indicated that have been better homogeneity and stability between 0.5 MPa and 10 MPa and an estimated relative expanded uncertainty of 5%(k=2)with one year shelf life have been achieved.