固体进样-冷原子吸收法直接测定土壤中总汞

应用固体测汞仪,采用多标准土壤样品(n20)绘制校准曲线法和单一标准土壤样品绘制校准曲线法,分别对土壤中的汞进行测定。结果表明,两者的方法检出限分别为0.30、1.49 ng,平行样(n=6)的相对标准偏差分别为3.6%~4%、5.4%~9.0%,90 d内的重复性精密度为4.1%,对国家土壤标样进行测定,结果与标准值相符。表明与单一标准土壤样品绘制校准曲线法相比,多标准土壤样品绘制标准曲线法具有更好的精密度、更低的检出限,更强的适用性,并且由于校准曲线长期稳定性,有效缩短土壤中汞的检测周期。

Dtermination of Mercury with Multi-Point Calibration Curve in Soil by Direct Analyzer with Solid Sampling

Total mercury in the state standard soil samples were determined using direct analyzer with solid sampling by multi-state standard soil-calibration curve and single-state standard soil-calibration curve. The results showed that the detection limits were 0.30 and 1.49 ng,the relative standard deviations of parallel samples(n=6)were 3.6%-4% and 5.4%-9.0%,the repeatability precisions in 90 days was 4.1%.This suggested that the method of multi-state standard soil-calibration curve had the lower detection limit,the better replicability precision,and the better reproducibility precision.