默认题库 - 船舶电气与船舶安全

单选题

If the PSCO has clear grounds for carrying out a more detailed inspection, （）should be immediately informed of these grounds.

A. the master
B. the chief engineer
C. the owner of the ship
D. the manager who assumes the responsibility for operation of the shi

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单选题

A cargo hold has been determined to have a relative humidity of 80% and a dry bulb temperature of 80 ℃ and a dry bulb temperature of 85℃.When the hold is sealed and the dry bulb temperature decreases, the relative humidity in the space will （）

A. decrease
B. increase
C. decrease to zero
D. remain unchanged

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单选题

A purge recovery system is used in a centrifugal air conditioning or refrigeration system to （）

A. purge lube oil from the liquid refrigerant
B. recover water purged from the system
C. separate foul gases from the receiver
D. purge non-condensable gases without losing refrigerant

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单选题

The（）enables water to be blow down or emptied from the boilerIt may be used when partially or completely emptying the boiler.

A. main stem stop valve
B. auxiliary steam stop valve
C. feed check or control valve
D. blow down valve

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单选题

As the amount of moisture in the air increases, the difference between the dry bulb and wet bulb temperature will （）.

A. increase
B. decrease
C. remain unchanged
D. be greatest at dew point

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单选题

The power factor of an AC generator operating singularly is determined by the （）

A. connected load
B. prime mover speed
C. field excitation
D. generators rated voltage

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单选题

After changing out the fuel filters the diesel engine fails to restart, the most probable cause for this condition is a/an（）.

A. low compression
B. air-bound fuel system
C. improper spark
D. change in viscosity

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单选题

One remedy for a high firing pressure, in addition to a high exhaust temperature in one cylinder of a diesel engine, is to （）

A. increase scavenge air pressure
B. reduce fuel booster pump pressure
C. adjust the fuel rack
D. retard fuel injector timing

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单选题

Which of the following conditions is most likely to occur when unburned fuel contaminates the crankcase of a diesel engine?（）

A. Lube oil is diluted and its viscosity is reduced
B. Sulfuric acid is formed
C. Bearings become pitted ad immediately fail
D. Valve stems develop sludge deposit

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单选题

Modern marine diesel engines equipped with mechanical fuel injection operate on a combustion phase within the cycle which is（）

A. entirely constant pressure
B. entirely constant temperature
C. a combination of constant volume and constant pressure
D. a combination of constant temperature and constant pressure

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