They were principally used to catalyze aldol, allylation, Diels - Alder, ene and Friedel - Crafts reactions.它们主要被用来催化Aldol, 烯丙基化, Diels-Alder, Ene和 Friedel -Crafts等反应....
Clothing which is fire - resistant in air maybe readily ignitable in oxygen - enriched atmospheres .在空气中防火的衣服在 富氧 大气中可能很容易着火.The atmospheres of Mars and the Earth are very different.火星与地球的大气层是很不相同的.It's quite import...
他矮壮结实，脖子很粗。He was short and stocky, and had a thick neck.他矮壮的体形总是让他觉得羞愧。He always feels ashamed for his short, stocky figure.这个男孩身体矮壮,生着一张丑陋却讨人喜欢的泰姆纳人的扁阔的面孔.The boy was shot and squat with the broad ugly pleasant face of...