电感耦合等离子体法测定金属中铅的不确定度评定  

Evaluation of Uncertainty of Determination of Lead in Metal by ICP-AES

作　　者：郑伟娟 ZHENG Weijuan(Shenzhen Academy of Metrology&Quality Inspection,Guangdong Shenzhen 518000,China)

机构地区：[1]深圳市计量质量检测研究院,广东深圳518000

出　　处：《广州化工》2024年第19期119-122,共4页GuangZhou Chemical Industry

摘　　要：根据GB/T 39560.5-2021中金属材料的通用消解方法7.2.2对金属样品进行消解,待样品完全溶解后进行定容,采用电感耦合等离子体发射光谱法(ICP-AES)进行铅含量的测定。分析实验过程和不确定度数学模型,从人、机、料、法、环等方面识别实验过程中测量不确定度的来源,绘制出相应的因果图。本次评定不确定度的来源包括样品称量、消解液定容、标准溶液浓度、工作曲线拟合、测量重复性以及加标回收率。对不确定度分量进行计算,得出实验不确定度最大的是加标回收率,其次为标准溶液浓度,结论给出降低各不确定度分量贡献值的建议和办法。结果为金属样品的铅含量为166 mg/kg,扩展不确定度为7 mg/kg,k=2。According to the general digestion method 7.2.2 of metal materials in GB/T 39560.5-2021,the metal sample was digested.After the sample was completely dissolved,it was fixed to volume and the lead content was determined by inductively coupled plasma atomic emission spectroscopy(ICP-AES).The experimental process and mathematical model of uncertainty were analyzed,the sources of measurement uncertainty during the experimental process were identified,and a causal diagram was drew.The sources of uncertainty were analyzed,including sample weighing,digestion solution constant volume,standard solution concentration,working curve fitting,measurement repeatability and spiked recovery rate.The uncertainty components were calculated,the highest uncertainty was the recovery rate of spiked samples,followed by the concentration of standard solutions.Finally,suggestions and methods were provided to reduce the impact of each component.The results showed that the lead content was 166 mg/kg,the expanded uncertainty was 7 mg/kg,k=2.

关 键 词：不确定度 ICP-AES 金属 铅 

分 类 号：TQ139.2[化学工程—无机化工]