硅钼蓝分光光度法测定钛铁矿中二氧化硅不确定度评定

Evaluation of the Uncertainty in Determination of Silicon in Titanite by Silicomolybdic Blue Spectrophotometry

摘要: 对硅钼蓝分光光度法测定钛铁矿中SiO2含量的不确定度进行评估,建立了数学模型,认为测量过程中不确定度主要来源于标准物质、样品制备、曲线拟合,以及重复实验产生的不确定度.当SiO2平均含量为0.67%时,评定其扩展不确定度为0.05%(k=2).

Abstract: The measurement uncertainty of silicon determination results for titanite samples by silicomolybdic blue spectrophometry was evaluated and the mathematical model of uncertainty expression was also established. The main sources of measurement uncertainty came from the sub-uncertainties of standard reference materials, sample preparation, calibration curve fitting and repetitive experiments. When the average concentration of SiO2 in samples was 0.67%， the expanded uncertainty was 0.05% (k=2).