摘要
目的对石墨炉原子吸收光谱法测定绿茶中镉的全过程进行分析,分析不确定度的影响因素,并对其不确定度进行评定。方法按照国标方法 GB 5009.15-2014进行检测,依据JJF 1059.1-2012的要求对测量结果进行评定。结果当绿茶中镉含量为146μg/kg时,其扩展不确定度为9.34μg/kg(k=2)。各个分量中样品预处理对结果影响最大,占71.7%,其次是测定样品溶液中镉浓度的不确定度占27.6%。结论用石墨炉原子吸收光谱法评定茶叶中金属元素的不确定度时有必要考虑样品预处理这一项。在实际工作中严格控制样品消化处理过程是降低不确定度的关键。
Objective To analyze the whole determination process of cadmium（Cd） in green tea by graphite furnace atomic absorption spectrometry,study the influencing factors of uncertainty,and evaluate the uncertainty. Methods The cadmium content in green tea was detected by graphite furnace atomic absorption spectrometry according to the national standard method of GB/T5009.15-2014. The uncertainty of measurement results was evaluated in accordance with the requirements of JJF 1059.1-2012.Results The result showed that the expanded uncertainty was 9.34μg/kg（k=2） when the Cd content in green tea was 146μg/kg.The effect of sample pretreatment on the result uncertainty was 71.7% in all components,and the next in importance was the uncertainty of cadmium concentration in the sample solution,accounting for 27.6%. Conclusions It was necessary to consider the sample pretreatment for evaluating the uncertainty of metal elements in tea by graphite furnace atomic absorption spectrometry.Strict controlling of sample digestion process was the key to reduce the uncertainty in practical work.
作者
王艳敏
周鸿
刘源
WANG Yanmin ZHOU Hong LIU Yuan.(Jiangxi Province Center for Disease Control and Prevention ,Nanchang 330029, Chin)
出处
《实验与检验医学》
CAS
2017年第1期23-27,共5页
Experimental and Laboratory Medicine
基金
江西省卫生计生委科技计划项目(20166003)
江西省卫生计生委科技计划项目(20166004)
关键词
石墨炉原子吸收光谱法
绿茶
镉
不确定度
Graphite furnace atomic absorption spectrometry
Green tea
Cadmium
Uncertainty
