在阅读外文科技文献时常遇到许多元素含量表示单位,有时同一含量采用不同的单位或不同的方式表示。在某些情况下,为了把不同来源的数据相比较,还要进行一些换算。为便于参考,特将某些常用单位整理如下。一、单位的定义 In the reading of foreign science and technology often encounter many elements of the unit, sometimes the same content in different units or different ways. In some cases, some conversions are needed to compare data from different sources. For ease of reference, especially some of the commonly used units collated as follows. First, the definition of unit