摘要
根据SH/T0663-1998,采用气相色谱法对车用乙醇汽油中的乙醇含量进行分析。通过乙醇测量不确定度的数学模型,分析了不确定度的来源,从内标纯度、称量过程、峰面积测量、线性拟合、方法重复性5个方面对测量不确定度进行了评定,指出线性拟合是对结果不确定度贡献最大的影响因素。论文同时也比较了内标法和外标法在乙醇含量不确定度评定中的差异,外标法的不确定度较大,主要来源有方法重复性和峰面积测量。
The uncertainty for the determination of ethanol in vehicle alcohol gasoline by gas chromatography was analyzed. The sources of the uncertainty which resulted from purity of internal solution, the weight of the sample, linear fitting, peak areas and method were studied according to mathematical model. At last the combined standard uncertainty and the expanded uncertainty were reported. Through evaluation it was indicated that the factor mostly affecting the uncertainty for the determination of ethanol was the uncertainty of linear fitting. The difference between external standard method and internal standard method on uncertanity were discussed. Compared with internal standard method, the relative standard uncertanity of methods and peak areas was large, so the uncertainty of external standard method is large.
出处
《化学工程师》
CAS
2010年第2期59-62,共4页
Chemical Engineer
