气相色谱仪测定蔬菜中三唑酮含量不确定度的评定

Uncertainty Evaluation of Determination Method for Triadimefon Residues by Gas Chromatography in Vegetables

采用气相色谱仪测定蔬菜中的三唑酮含量,评定其不确定度。影响蔬菜中三坐酮含量不确定度的因素包括Cs的不确定度、测量重复性的相对标准不确定度、温度变动引起标准溶液浓度的不确定度、贮备液配制的标准不确定度、称量和定容的不确定度、标准贮备液配制标准溶液的不确定度。根据测量原理,建立数学模型,通过对各标准不确定度分量分析计算,求出合成不确定度uc(X)和扩展不确定度U(X)。结果表明,用气相色谱仪测定蔬菜中三唑酮含量结果的不确定度主要来自试样的重复性试验和由三唑酮标准溶液5个浓度点的响应值所得的拟合直线产生的。

Triadimefon contents in vegetables were measured by gas chromatography,the uncertainty was evaluated.There were six factorsinfluencing the uncertainty of the content of triadimefon in vegetables,such as the uncertainty of Cs,the relative standard uncertainty of measurementrepeatability,the uncertainty of standard solution concentration caused by temperature change,the standard uncertainty of preparation of stocksolution,the uncertainty of weighing and constant volume,the uncertainty of standard solution prepared by standard stock solution.According to themeasurement principle,a mathematical model was established,and the composite uncertainty uc（X）and the extended uncertainty U（X）were obtainedby analyzing and calculating the components of each standard uncertainty.The results showed that the uncertainty of the determination of triadimefoncontent in vegetables by gas chromatograph mainly came from the reproducibility test of the sample and the fitting line obtained by the response value ofthe 5 concentration points of the triadimefon standard solution.