GC/MS测定水中三氯乙醛的不确定度评定

系统介绍了吹扫捕集气相色谱/质谱法测定水中三氯乙醛不确定度评定过程,对吹扫捕集气相色谱/质谱法测定水中三氯乙醛的测定过程进行分析,通过数学模型分析并计算测试过程中的不确定度分量,最后计算出相对合成标准不确定度和相对扩展不确定度。结果表明,吹扫捕集气相色谱/质谱法测定水中三氯乙醛的不确定度主要有四个来源:标准样品浓度及稀释过程,标准曲线及回归偏差,样品取样量,仪器稳定性。

Uncertainty Evaluation of Determination of Chloral in Water with GC/MS

The uncertainty of determining chloral in water was evaluated by purge and trap-gas chromatography-mass spectrometry（purge trap-GC-MS）.The determination process of chloral in water was analyzed by purge trap-GC-MS.The uncertainty factors in analyzing process were determined and calculated by mathematic model,and the relative synthesis standard uncertainty and the relative expansion standard uncertainty were calculated out.The four main sources were the uncertainty of standard samples and by dilution process,the uncertainty of linear and regression variance,the uncertainty brought in the sampling process,and the uncertainty resulted from the instrument stability of purge trap-GC-MS.Four main sources of the uncertainty of determining chloral in water by purge trap-GC-MS was determined.The uncertainty evaluation process of determining chloral in water by purge trap-GC-MS was introduced systematically.