摘要
目的评估二次热解吸—气相色谱法测定空气中苯的不确定度。方法通过明确被测量,识别分析不确定度来源,量化各不确定度分量后合成标准不确定度,进而得到扩展不确定度。结果二次热解吸—气相色谱法测定空气中的苯,在95%置信概率下,包含因子k=2时,扩展不确定度为9.4%。结论该方法中标准溶液配制和标准曲线拟合的不确定度分量对合成不确定度贡献最大,可通过选择不确定度较小的标准品、器具和仪器,提高标准曲线点数并多次测量,提高测试人员熟练程度来降低不确定分量,进而降低扩展不确定度。
Objectives To evaluate the uncertainty of benzene determined by two-stage thermal desorption-gas chromatography. Methods Identifying the source of uncertainty, expressing the combined standard uncertainty and expended uncertainty by calculating the component of uncertainty. Results The expended uncertainty was 9.4% when the confidence level was 95% and the coverage factor was 2. Conclusions The largest contributions of components were the preparation of standard solution and the procedure of standard curve fitting. These components could be cut down by using standard product and apparatus with low uncertainty, adding the dots and measuring times of standard curve fitting, and enhance the ability of personnel in experimentation. Thereby the value of ex- pended uncertainty would be decreased.
出处
《环境卫生学杂志》
北大核心
2012年第5期240-243,F0003,共5页
JOURNAL OF ENVIRONMENTAL HYGIENE
关键词
不确定度
二次热解吸
气相色谱法
苯
uncertainty, two-stage thermal desorption, gas chromatography, benzene
