middle elements calcium and sulfur

• 中量元素钙硫

middle elements calcium and sulfur的用法和样例：

例句

1. K2CO3 was added to the natural water sample for preprocessing, and the main interfering elements, i.e.calcium and magnesium, could then be conveniently separated from lithium.
   在天然水样中加入碳酸钾进行预处理，方便地分离了锂的主要干扰元素钙和镁。