原油稳定工艺中,当只要求塔顶产品的质量时,可采用()。
A.精馏法
B.提馏法
C.全塔分馏法
D.加热闪蒸法
参考答案:A
The old woman ______ her sons and daughter ______ and see her from time to time.
A.suggested; to come
B.desired; coming
C.desired; to come
D.hoped; to come
将振源隔离,使其产生的振动不向周围传播,这属于()。
A.积极隔振
B.消极隔振
C.被动隔振
D.B+C