气相色谱法测定果蔬中毒死蜱的不确定度评定

Evaluation of Uncertainty in Determination of Chlorpyrifos Residue in Fruits and Vegetables by Gas Chromatography

对气相色谱法测定果蔬中毒死蜱残留的不确定度进行评定。通过对测定过程中各变量的分析,确定了不确定度来源,建立了数学模型,计算出了各变量的不确定度,最后计算出合成不确定度。当果蔬中毒死蜱残留量为0.218μg/g时,测定结果的扩展不确定度为0.022μg/g(k=2)。

The uncertainty of determination of chlorpyrifos residue in fruits and vegetables by gas chromatography was evaluated. By analyzing the various variable parameters among the procedures, the components of uncertainty were identified, the mathematical model was established, and every components of uncertainty was calculated, thereby, the combined uncertainty was finally obtained. The expanded uncertainty was 0. 022 μg/g （ k=2 ） with 0. 218 μg/g of the content of chlorpyrifos residue in fruits and vegetables.