在1,2--二亚甲基环丁烷中并不发生这种现象.This phenomenon does not occur with 1 - 2 - dimethylenecyclobutane.环丁烷主要成 “ 蝶式 ” 构象存在.Cyclobutane exists predominantly in a " butterfly " conformation.四 号 溶剂主要成分为液化丁烷.The main component in 4 # solv...
Casting for auto parts ( calliper, bracket, disc, pressure plate etc ), reerigerator and air conditioner compressor parts ( cylinders, crankshaft etc ), machinicalparts, construction parts , motorparts, pump parts etc.汽车...
Just as I started to think that I was never going to get well, the illness began to recede...正当我开始觉得自己永远都好不了了的时候，我的病开始好转了。...a youngish man with dark hair just beginning to recede...前额黑发刚开始脱落的年轻人The colleges would recede...