英语语法分析

Total sugar in the pretreated wheat straw and the fermented residue decreased.

盐酸预处理和发酵产氢后麦草秸秆中总糖降低了。

The molasses should be pretreated before being used as a raw material for fermentation medium.

在用于发酵培养基时，糖蜜应该象其他原料一样在作为发酵培养基使用前进行预处理。

The molecular sieve pretreated by alkali can improve the stability of catalysts obviously.

分子筛预先经碱处理，能够明显改善催化剂稳定性。