混合指示剂有哪几种？使用混合指示剂有什么优点？

板式换热器属于混合式换热器。

按照换热方式的特点，换热器可分为三类：间壁式换热器、蓄热式换热器和混合式换热器。

按照换热方式进行分类，换热器可分为蓄热式换热器、混合式换热器和（）。

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.

逻辑运算符（AND、NOT、OR）的运算顺序是AND→OR→NOT。

换热器采用逆流操作的优点有哪些？

逻辑运算符（AND、NOT、OR）的运算顺序是AND→OR→NOT。