【摘要】 为保证农作物生长环境中重金属的检测质量,科学地评定检测结果的分散性,依据国家标准方法和测量不确定度评定与表示的理论,以农业灌溉区地表水为例,评定了石墨炉原子吸收法测定地表水中镉的不确定度。测得地表水样中镉的浓度为2.15μg/L,扩展不确定度U95=0.19μg/L(k=2)。结果表明,利用该法测定地表水中的重金属时,对其合成标准不确定度的主要贡献来自仪器分析过程。更多还原

【Abstract】 Aiming to ensure the quality of determining heavy metals from growth environment of crops,and evaluate the dispersancy of results,the uncertainty of measuring cadmium(Cd) in surface water collected from an agricultural irrigating area by graphite furnace atomic absorption spectrometer was evaluated on the base of the theory of evaluation and expression of uncertainty in measurement.Cd was detected at a concentration of 2.15 μg/L in the surface water,and 0.19 μg/L of the expanded uncertainty,U95(k=2),was obtained in the method.The result indicated that the combined standard uncertainty of using such method to determine heavy metals in surface water mainly derived from instrument analysis.更多还原