arsenic

Single calcium carbonate or single calcium oxide reacts with arsenic compounds under high temperature and generates calcium arsenic which is hard to discompose. By adding a small amount of these substances, their arsenic-capturing rates are up to 73.0% and 47.4% respectively.

单一的碳酸钙或氧化钙在高温下与砷化物作用，生成难分解的砷酸钙，加入少量这些物质，其固砷率分别可达73.0%、47.4%。

All the content of soluble speciation of arsenic in water is very low, the content of arsenic in free subsiding water is much higher. So the arsenic in free subsiding water is actually this in suspended solid matter.

水体中溶解态砷含量均较低，自然沉降水样中砷含量较高，故自然沉降水中砷实际上是水中悬浮性固体所含的砷，而黄河水中泥沙含量与砷含量呈紧密正相关。

Chemical characteristics of arsenic, environmental background and sources and cycles of arsenic, chemical equilibria including precipitation dissolution, oxidation reduction, adsorption desorption of arsenic, as well as effects of microorganisms on arsenic transformation in soils were reviewed in detail.

本文比较详细地综述了砷的化学特性，环境背景值及来源和循环，土壤中砷的三大化学平衡即沉淀溶解平衡，氧化还原平衡，吸附解吸平衡，以及微生物对砷的转化。