He decided that he might fire at all gnats.他决定索性把鸡毛蒜皮都摊出来.Gnats and mosquitoes infested the field by the river.小昆虫和蚊子群集于河边的田野里.Swarms of gnats and mosquitoes pestered them. Rattlesnakes and grizzly bears were a constant ...
Copper - containing catalysts are the most suitable catalysts for producing 1, 2 - propanediol through catalytic hydrogenolysis of glycerol.对甘油催化氢解制取1, 2- 丙二醇效果最好的是含铜的催化剂....