Application of samarium diiodide in mediating intramolecular cyclization reactions was reviewed.综述了二碘化钐在分子内环化反应中的应用.Sodium ethylate was used as catalyst in Baker - Venkataraman of cyclization, and all factors were studie...
他把行李寄存在车站.He checked his luggage at the station.双极型移位寄存器可分为单向和双向两种.Biolar shift registers are classified as unidirectional and bidirectional.对于三个寄存器我们可以随意假定每种寄存器规定的动作.We might arbitrarily assume for each of the three reg...
before的近义词有：ago, before,before, in front of, in the front of。下面这两个副词均含"……以前"的含义：ago ：指从现在起往前推算一段时间，始终置于所修饰的词之后，与一般过去时连用。before ：或指从过去某一时间起向前推算的若干时间的以前，通常与过去完成时连用；或泛指以前，并不具体指若干时间以前，可使用现在完成的或过去时；还可指从将来某一时间起的若干时间以前。下面这些前置词(...
They were spotted after three hours adrift in a dinghy.他们在小舢板上漂浮了3个小时后才被发现。The three of us manhandled the uncovered dinghy out of the shed.我们三个人把无篷小划艇推出了棚子。The dinghy gathered speed as the wind filled her sails.风鼓起了帆,小帆船...