There has been a modest upturn in most parts of the industry.该行业的绝大部分领域都出现了一定程度的好转。They do not expect an upturn in the economy until the end of the year...他们预测要到年底经济才能有所好转。Experts have forecast an upturn in the stock mar...
The selectivity of extractant is high and only Au, Pd , Hg ete. are extracted.该萃取剂选择性高,它仅萃取Au 、 Pd和Hg等几种元素.An extractant - screening method with a vapor - liquid equilibrium apparatus in the extractive distillation was i...