Laborda F, Górriz M P, Castillo J R
Analytical Spectroscopy and Sensors Group, Department of Analytical Chemistry, University of Zaragoza, Zaragoza, Spain.
Talanta. 2004 Oct 20;64(3):631-6. doi: 10.1016/j.talanta.2004.03.030.
Ultrasonic slurry sample introduction was applied to the determination of total chromium in composted materials by electrothermal atomic absorption spectrometry (ETAAS). The effect of grinding on the heterogeneity of the test samples and on the attainable precision was studied. The repeatability was influenced by the heterogeneity of the test samples at the mug-level, the R.S.D. of the measurements being 15%. The reproducibility depended on the heterogeneity of the test sample at the mg level, and it could be improved from 11 to 7% by increasing the grinding time. The characteristic mass was 2.6pg and the detection limit for the optimised procedure at the 0.04% (w/v) slurry concentration, 370ngg(-1). Good agreement with a certified reference material and with the conventional microwave assisted digestion method was found by using external calibration with aqueous standards. The performance of the method for screening purposes was evaluated.
采用超声悬浮液进样，通过电热原子吸收光谱法（ETAAS）测定堆肥材料中的总铬。研究了研磨对测试样品不均匀性及可达到的精密度的影响。重复性受杯级测试样品不均匀性的影响，测量的相对标准偏差（R.S.D.）为15%。再现性取决于毫克级测试样品的不均匀性，通过增加研磨时间，可将其从11%提高到7%。特征质量为2.6pg，在0.04%（w/v）悬浮液浓度下，优化程序的检测限为370ng g⁻¹。通过采用水标准溶液进行外标法，发现该方法与有证标准物质以及传统微波辅助消解方法具有良好的一致性。对该方法用于筛选目的的性能进行了评估。
