[Determination of heavy metals in artificial soil on railway rock-cut slopes by microwave digestion-AAS].

The purpose of this paper is as follows :(1) Optimizing the parameters of microwave digestion-atomic absorption spectroscopy (AAS) and establishing method for the determination of heavy metals in artificial soils. (2) Evaluating heavy metal pollution conditions in artificial soil samples from railway rock-cut slopes.The results showed that the mixture of HNO3-H2O2-HF was found to have the best digestion efficiency ; under the optimized conditions,the recoveries of the method ranged from 95%to 105% ; the measurement precision and the relative deviation were less than 4%and 5%,respectively ; the concentrations of Cd,Pb and Zn were significantly higher in the artificial soil on railway rock-cut slope than in the control soil,and they were 4.7,1.3 and 1.2times as much as the control soil,respectively ; compared to the contents of Cr,Cu and Fe in control soils,there was no significant difference.This research will provide a reliable method for determining metal elements in artificial soils on rock-cut slopes and a theoretical basis for the management of the railway rock-cut slopes.