更多"It should be ensured that only （） v"的相关试题:
[单项选择]A stage should only be rigged（）.
A. over the bow or stern of a vessel
B. over the flat sides of a vessel
C. over the open water
D. over the dockside
[单项选择]A fuse that blows often should be replaced only with a fuse of （）.
A. the recommended current and voltage rating
B. higher current and voltage rating
C. higher current and lower voltage rating
D. lower current and higher voltage rating
[单项选择]In a vapor compression refrigeration the evaporating pressure is maintained constant by the action of the （）, which removes vapor from the evaporator at the same rate at which it is formed.
A. evaporator
B. compressor
C. condenser
D. none of the above
[单项选择]Reid vapor pressure is（）.
A. exerted by liquid cargo on the sides of a tank
B. exerted by liquid cargo on a cargo hose body
C. the lowest temperature and pressure that will cause a flammable liquid to give off vapors
D. a measurement of the amount of flammable vapors given off by a liquid at a certain temperature
[单项选择]Reliable delivery of messages is ensured by（）techniques.
A. forward error correction
B. aftward error correction
C. DGPS
D. error-free and low error reception
[单项选择]Relative humidity is the percentage of water vapor that is in the air as compared to the maximum amount it can hold at（）.
A. a specific barometric pressure
B. a specific temperature
C. a specific wind speed
D. any time
[单项选择]The evaporating pressure in R22 vapor compression refrigeration plant should be （） atmospheric.
A. below
B. above
C. equal to
D. much larger than
[单项选择]Fueling activities（）waste liquids and vapor releases to air.
A. commence
B. generate
C. give
D. have
[单项选择]When flammable liquids are handled in a compartment on a vessel，the ventilation for that area should be（）.
A. operated continuously while vapors may be present
B. operated intermittently to remove vapors
C. available on standby for immediate use
D. shut down if an explosive mixture is present
[单项选择]Before entering a tank，always check the vapor content（）a combustible gas indicator.
A. with
B. by
C. of
D. for
[单项选择]Every liquid has a pressure at which it will vaporize and this pressure varies with temperatureThe word “which” means （）.
A. a liquid
B. a pressure
C. a temperature
D. none of the above
[单项选择]The latent heat of water vapor in air is dependent upon the （）
A. dry bulb temperature
B. wet bulb temperature
C. dew point
D. dry point
[单项选择]When a crankshaft has to be handled outside the engine, it should be carefully supported in a manner which will avoid （） high bending moments on it.
A. compressing
B. interposing
C. imposing
D. pounding
[单项选择]The heat used to change a liquid to a vapor is called （）.
A. latent heat of fusion
B. latent heat of vaporization
C. specific heat of vaporization
D. latent heat of the gas
[单项选择]Gasoline vapor tends to collect（）.
A. above the floor plates of the bilges
B. above the carburetor level
C. at the lowest point of the bilge areas
D. at no particular level
[单项选择]The lowest temperature at which the vapor formed from a liquid ignites and continues to burn steadily in the presence of an ignition source is called the（）.
A. flash point
B. fire point
C. upper explosive limit
D. lower explosive limit
[单项选择]The effect of high vapor superheat in a refrigeration system, is a/an （）.
A. increased capacity of the compressor
B. more efficient operation of the thermal expansion valve
C. decreased capacity of the compressor
D. loss of receiver capacity
