乙烯直接氧化生产乙醛的“一步法”中，为什么不能使用空气作氧化剂？

乙烯直接氧化生产乙醛的“一步法”中，哪种原料过量？它给后续工艺带来什么影响？

为什么向电收尘器内送负电？

翻译：With Average or With Particular Average（WA or WPA）（）

按照生产工艺的特点来设置生产单位称为什么？

Every deliberate act of wrongdoing by the master or any of the crew against the ship or cargo，without the authorization or privity of the Shipowner or his agent，is（）.

（）, or drum is used for hauling in or letting out the wires or ropes which will fasten the ship to the shore.

A salvor may be（）the whole or part of the payment due under Salvage Convention to the extent that the salvage operations have become necessary or more difficult because of fault or neglect on his part or if the salvor has been guilty of fraud or other dishonest conduct.

绿色生产工艺是在绿色化学的基础上开发的从（）的生产工艺。

逻辑运算符（AND、NOT、OR）的运算顺序是AND→OR→NOT。

天然气部分氧化工艺在生产上有哪些特点？

逻辑运算符（AND、NOT、OR）的运算顺序是AND→OR→NOT。