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单选题
Because of the reduced （） in the vacuum boiling evaporator, some of the sea water boils as it flows through the tubes.
A
temperature
B
water level
C
pressure
D
rate of flow
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单选题When distilling sea water the cooling water discharging from the distiller is fed back to evaporator as feed water （）.A
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单选题What is the operating principal of a flash type evaporator?（）A
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单选题In （）, hot diesel engine jacket water passes over the stack and heats the sea water passing through the tubes.A
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单选题With a vacuum boiling evaporator, the remainder of sea water fed to the evaporator is pumped out by （）.A
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单选题Which of the following descriptions best identifies the operating principal of a flash-type evaporator?（）A
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单选题Which of the listed conditions will cause the feed water that has not flashed to vapor in the first-stage of a flash evaporator, to flow into the second-stage?（）A
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单选题In towing it is desirable for the tug and the vessel to ride wave crests simultaneously because（）.A
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单选题Which one of the followings might not be employed to create vacuum for flash type evaporator? （）A
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an air ejectorC
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单选题When a vacuum boiling evaporator works, the hot jacket water will pass over the tube stack and （） the sea water passing through the tubes.A
disposeB
dissolveC
heatD
dissipates
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单选题A vacuum is initially established in the first and second stages of a low pressure evaporator by the use of （）A
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wear on the towline is equalizedB
weight of the towline increases the towing forceC
dip in the towline absorbs shock loadsD
danger of overriding is reduced
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