皮革中重金属总量的测量不确定度评定(续)

Evaluation of measurement uncertainty for determination of total heavy metal in leather

采用微波消解-电感耦合等离子体原子发射光谱法(ICP-AES),对皮革中9种重金属(砷、镉、钴、铬、铜、汞、镍、铅、锑)总量进行分析测试。依据国家计量技术规范《JJF 1059.1-2012测量不确定度评定与表示》,系统分析了ICP-AES法测定皮革中9种重金属总量过程中测量不确定度的来源。识别了测定过程中的不确定度,主要来源于称样量、定容体积、方法回收率、测量重复性、校准溶液的配制、标准曲线的绘制等。通过对各不确定度分量进行定量评估、合成,最后分别得到9种重金属总量测量的合成标准不确定度和扩展不确定度。

Total contents of nine heavy metal elements as As, Cd, Co, Cr, Cu, Hg, Ni, Pb and Sb in leather were analyzed by inductively coupled plasma atomic emission spectrometry （ ICP - AES） after procedure of microwave digestion. According to national metrology technical specifications 《JJF 1059. 1 - 2012 ： Evaluation and Expression of Uncertainty in Measurement》, the sources of measurement uncertainty for the total contents of nine heavy metal elements determination by ICP - AES, were investi- gated. Main sources of measurement uncertainty in total contents of heavy metal determination in leather were identified, and the sources were as follows ： weight of sample, volume of dilution, recovery of the method, measurement repeatability, preparation of calibration solution, preparation of calibration curve and so on. After the quantitative assessment and synthesis of the individual component uncertainty, combined standard uncertainty and expanded uncertainty in the measurement for total contents of the nine heavy metal elements were obtained.