摘要
目的分析讨论石墨炉原子吸收光谱法测定饮用水中镉过程中不确定度的因素,从而找到影响测定结果准确性的主要原因,为更准确测定饮用水中的镉提供帮助。方法采用石墨炉原子吸收光谱法,测定饮用水中镉,获取一定的实验数据,依据JJF1059-2012《测量不确定度评定与表示》建立数学模型,分析和计算不确定度。结果用石墨炉原子吸收光谱法测定饮用水镉的含量时,标准溶液带来的相对标准不确定度Urel(1)为0.001,由体积引入的相对标准不确定度Urel(2)为0.0071,曲线拟合过程中产生的相对标准不确定度Urel(3)为0.070,样品重复测定引入的相对标准不确定度Urel(4)为0.017,石墨炉进样时引入的相对标准不确定度Urel(5)为0.00075。合成标准不确定度为0.072μg/L,扩展不确定度为0.092μg/L。结论用石墨炉原子吸收光谱法测定饮用水镉的含量时,标准曲线拟合和重复测定是不确定度的主要来源。
Objective To analyze and discuse the graphite furnace atomic absorption spectrometry determination of cadmium in drinking water in the process of uncertain factors,to find the main reason for the accuracy of the results of the determination,for a more accurate determination of cadmium in drinking water to provide help.Method The determination of cadmium in drinking water by graphite furnace atomic absorption spectrometry was used to obtain some experimental data,and then the statistical analysis was made.Results We measured the determination of cadmium in drinking water by graphite furnce atomic absorption spectrometry and standard solution relative standard uncertainty degree Urel（1） is 0.001.introduced by the volume of the relative standard uncertainty degree Urel（2） is0.003 3,relative standard curve fitting process of uncertain degree Urel（3） is 0.014 4,repeated measurement of the sample introduction of the relative standard uncertainty degree Urel（4） is 0.024 8,graphite furnace injection is introduced when the relative standard uncertainty degree Urel（5）is 0.000 75.Conclusion When we measured the determination of cadmium content in drinking water by graphite furnace absorption spectroscopy,the uncertainty of standard curve fitting and repeated measurement are the main sources.
作者
钟叶芳
段先兵
ZHONG Yefang DUAN Xianbing(Center for Disease Control and prevention of Dayawan District ,Huizhou Guangdong 516211, China Center for Disease Control and prevention of Huiyang District ,Huizhou Guangdong 516200 , China)
出处
《河南预防医学杂志》
2017年第4期272-274,276,共4页
Henan Journal of Preventive Medicine
关键词
石墨炉原子吸收光谱法
不确定度
饮用水
镉
Graphite furnace atomic absorption spectrometry
The uncertainty
Drinking water
Cadmium
