正己烷、正己醇和苯在正相色谱中的洗脱顺序依次为（）。

Keyboard Error or no keyboard present.表示哪个配件有问题（）

在液-液分配色谱中，下列固定相／流动相的组成属于正相色谱的是（）

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.

The （） is used for hauling in or letting out the wires or ropes.

Vessels must be（）valid certificate of nationality or certificated of registry or license.

When loading or discharging dry mud or cement，crew members should use goggles and（）.

逻辑运算符（AND、NOT、OR）的运算顺序是AND→OR→NOT。

正已烷、正已醇、苯在正相色谱中的洗脱顺序为（）

逻辑运算符（AND、NOT、OR）的运算顺序是AND→OR→NOT。