The mass fraction of n - butene in mixed C 4 from catalytic cracking after etherized was approximately 40 %.醚化后的催化裂化混合C4中含有质量分数约为40%的正丁烯,是生产丙烯的优质原料....
He had been feeling drowsy, the effect of an unusually heavy meal.他一直感到昏昏沉沉的，这是吃了一顿超级大餐的结果。I felt dopey and drowsy after the operation.手术后我感到迷迷糊糊，昏昏欲睡。The tablets may make you feel drowsy.这药片可能会使你昏昏欲睡。...
埃迪将自动步枪的保险栓重新拉上。Eddie slipped the safety catch on his automatic back into place.给窗户装上安全锁或窗栓。Fit windows with safety locks or catches.他插上了门(栓).She bolted the door....