Isoamyl butyrate was synthesized by using ceric sulfate as the catalyst.以硫酸高铈为催化剂,正丁酸和异戊醇为原料合成了正丁酸异戊酯.In the presence of ethanonitrile and glycol, anisole reacts with ammonium ceric nitrate to form o - nitroanisole.在乙腈、聚...
窗户通常是封闭的。Windows are usually sealed off.他们接触的事不多,从这一方面来说这是个封闭的社团。It is a closed society in the sense that they've not been exposed to many things.宇宙究竟是开放的,还是封闭的?Is the universe open or closed?...
The field were so close that they would have caught us if I hadn't begun the sprint.其他参赛选手紧随身后,如果不是我开始冲刺,他们就会赶上我们了。She'd been caught from behind and hadn't a prayer of freeing herself.有人从后面抓住她,她不可能脱身。We ha...
所有的性激素, 例如雌激素 、 黄体酮和睾酮都是类固酮.All the sex hoymones, e . g. estrogens, progesterone, and testosterone, are steroids.所有的性激素, 例如雌激素, 黄体酮和睾酮都是类固醇.All the sex hormones, e . g . estrogens, progesterone, and testosterone, are ste...