7VanCott R J,McDonald B J,Seelos A G.Standard soil sample preparation error and comparison of portable XRF to laboratory A A analytical results[J].Nuclear Instruments and methords in Physics Research,1999,(a)422:801-804.
9Kazi T G,Jamali M K,Arain M B,et al. Evaluation of an ultrasonic acid digestion procedure for total heavy metals determination in environmental and biological samples [J]. J ttazard Mater. ,2009,161:1391-1398.
10Giingor H, Elik A. Comparison of ultrasound-assisted leac- hing with conventional and acid bomb digestion for deter- mination of metals in sediment samples[ J ]. Microchem J, 2007,86 : 65-70.
