硼氢化钾还原-气相分子吸收光谱仪测定水中的总汞及其不确定度的评定

以硼氢化钾代替二氯化锡作还原剂，用气相分子吸收光谱仪代替测汞仪，冷原子吸收法测定了水中总汞，按有关规范的原则和方法评定了其测量不确定度。结果表明，检出限为0．005μg／L，精密度RSD为1．O％，加标回收率为99．1％～103．1％，测定海洋局外控样和IERM测量审核样的结果良好，测定汞标样的相对误差为1．7％。此法测定样品的扩展不确定度为3．5％。

Determination of Total Mercury in Water by Potassium Hydroborate Reduction-Gas Molecules Absorption Spectrometer and Evaluation of Its Uncertainty

To replacing tin dichloride by the potassium hydroborate to make the reducing agent, and the mercury vapor analyzer by the gas phase molecular absorption spectrometer, with cold atomic absorption method, the total mercury was determined. This method has a simple and fast operation procedure, a low determination limit, a high accuracy and a good linearity relate. And it can reduce the spectrum interference also. Obtained detection limit is 0. 005 μg/L, precision is RSD = 1.0% , recoveries = 99. 1% ～ 103.1%. There are good results to determine the external control sample of oceanic administration and the measurement review IERM sample of state environmental protection. The relative error to determine standard sample of mercury is 1.7 percent. After evaluation of this article, the expanded uncertainty to determine samples with this method is 3.5 percent.