手洗餐具用洗涤剂中总活性物含量测定的不确定度评定

Evaluation of Uncertainty in the Determination of Total Active SubstanceContent in Hand Dishwashing Detergents

为提高手洗餐具用洗涤剂中总活性物含量测定结果的准确性,有必要对总活性物含量测定结果的影响因素进行分析和不确定度评定。依据GB/T 13173-2021《表面活性剂洗涤剂试验方法》标准中A法试验方法,从测量结果重复性引入的标准不确定度;样品质量称量引入的标准不确定度;乙醇萃取物质量称量引入的标准不确定度;硝酸银标准溶液浓度引入的标准不确定度;滴定管滴定体积引入的标准不确定度等进行合理评定,最后计算出合成标准不确定度和扩展不确定度,乘以95%置信概率下的扩展因子k=2,得到测量结果的相对扩展不确定度和报告结果。

In order to improve the accuracy of the determination results of total active matter content in hand dishwashing detergent,it is necessary to analyze the influencing factors and evaluate the uncertainty of the determination results.According to the test method A in“Test Method for Surfactant Detergent”(GB/T 13173-2021),the standard uncertainty is introduced from the repeatability of measurement results;The standard uncertainty introduced in sample mass weighing;The standard uncertainty introduced in the mass weighing of ethanol extract;The standard uncertainty of the introduction of silver nitrate standard solution concentration;The standard uncertainty introduced into the burette titration volume was evaluated reasonably.And the synthetic standard uncertainty and extended uncertainty were calculated at last,multiplied by the expansion factor k=2 under 95%confidence probability to obtain the relative extended uncertainty of the measured results and the reported results.