Although not covered by the rules, sulfur dioxide also could drop up to 90 percent because it would be filtered out by the same technology that controls hydrochloric acid.

尽管二氧化硫没有被纳入到此项法规中，但是由于控制氯化氢的技术也会去除二氧化硫，因此二氧化硫的排放量也会下降达90%。

These small tablets contain one drop of hydrochloric acid and they last about four hours.

这些小片剂每片含有一滴盐酸，药效持续四个小时左右。

Dissolve a pinch of silver and mercury in a solution of nitric acid, drop in a lump of metal amalgam, and soon a spidery, glittering "Tree of Diana" will form on the glass.

在硝酸中溶解少量银和水银，再扔一小块金属混合物，不久，蛛网一样的闪亮的“戴安娜之树”就会在玻璃上形成。

A problem related to nitrification is a drop in PH for the system due to the formation of nitric acid.

和硝化作用有关的一个问题就是由于生成硝酸而使系统内的PH值降低。

If all women took adequate folic acid before conception and during pregnancy, the number of babies born with a neural tube defect could drop by as much as 70 percent.

如果所有的妇女在怀孕前后获得足够的叶酸的话，该病的患病率可以下降70%。