So, we must analyze the causes of prestation unjustified enrichment and non-prestation unjustified enrichment and reconstruct its constitutive requirements.

因此，应该得利制度物权变动理论基础视角分别对给付型和非给付型得利物权变动原因进行分析，重新构建其构成要件。

The ore sample was dissolved in nitric acid.After enrichment and separation with Xanthic ester cotton,the silver was determined by thiocyanometry.

该方法采用硝酸溶解样品,黄原酯棉集分离,以硫氰酸盐滴定法进行测定。