原子荧光法测定稻谷中总汞含量的不确定度评定

Uncertainty evaluation for determination of total mercury content in paddy rice by atomic fluorescence spectrometery

中文关键词:  原子荧光法  总汞  稻谷  不确定度

英文关键词:atomic fluorescence spectrometry  total mercury  paddy rice  uncertainty

中文摘要:

      目的 建立微波消解原子荧光法测定稻谷样品中的总汞含量不确定度模型。方法 按照CNAS- GL006:2018的评估方法, 建立结果不确定度评估数学模型, 量化不确定度分量, 计算扩展不确定度。结果 经评定, 稻谷样品中总汞的测定结果为0.0338 mg/kg时, 扩展不确定度为0.020 mg/kg (k=2)。结论 影响总汞测定不确定度的主要因素是样品制备过程、重复条件下的标准偏差、标准物质。

英文摘要:

      Objective To establish a evaluation model of uncertainty for determination of total mercury in paddy rice samples by microwave digestion and atomic fluorescence spectrometer. Methods According to the CNAS-GL006:2018, a mathematical model for uncertainty evaluation was established. The component of uncertainty was quantified, and the expanded uncertainty was calculated. Results The expanded uncertainties of the methods was 0.020 mg/kg (k=2), when the determination results of total mercury were 0.0338 mg/kg. Conclusions The main factors affecting the uncertainty of total mercury determination are sample preparation process, standard deviation under repeated conditions and standard substance.