不同钵体研磨地质样品产生的元素污染及粒度分布探讨

Examination of Sample Particle Sizes and Element Contami-nation in Grinding by Using Different Kinds of Mortar Mills

采用玛瑙钵体碎样,随着研磨时间加长,样品粒度可以变得更细。但与碳化钨钵体相比,达到同样粒度所需研磨时间较长,且清洗困难,会造成样品之间的污染。用碳化钨钵体碎样,粒度在研磨4min后可达到70μm,但研磨5min和6min,粒度无明显变细。在两种钵体中,除碳化钨钵体对样品造成了严重的Co污染外,对所测定的其它微量元素,均未造成明显污染。

Grinding with agate mortars, sample particle sizes could become much smaller with increasing grinding time. But grinding to certain particle size needs much longer time than using tungsten carbide mortars. Agate mortars are difficult to clean up, which may cause the cross contamination of samples. With tungsten carbide mortars, sample particle size reaches to 70 μm within 4 minutes, but no apparent difference in 5 and 6 minute grinding time. Both tungsten carbide and agate mortars have no apparent trace element contamination from geological samples except for Co from tungsten carbide mortars.