使用GCMS测试土壤中多环芳烃含量的测量不确定度评定

Measurement Uncertainty Evaluation of PAHs Content in Soil by GCMS

利用气相色谱质谱联用仪(GCMS)来定值土壤中多环芳烃含量的标准物质的实验。依据标准要求,分析测量过程中的不确定度来源,建立数学模型,结合A类、B类不确定度评定的方法,分析标准溶液配制、拟合曲线、平行样测试、样品溶液定容、仪器稳定性、取样量、回收率等引入的不确定度分量,给出各个分量的直方图,采用替代物和内标加标回收率表征准确度,平行样试验来表征精密度的方法,来评定测量不确定度。

The experiment of fixed value for the determination of polycyclic aromatic hydrocarbons（ PAHs）（ reference materials,RM） by using gas chromatography mass spectrometry（ GCMS） was studied. According to the standard requirements,the measuring process of uncertainty source was analyzed,mathematical model was established,combined with Class A,B type uncertainty assessment method,for analysis of uncertainty components introduced by standard solution preparation,curve fitting,parallel test,the sample solution volume,the stability of the instrument,sampling quantity,the recovery rate,etc. The histogram of each component was given. The method of recoveries test to characterize accuracy by using surrogate and internal standard,and parallel test to characterize the precision,was used to the evaluation of measurement uncertainty.