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单选题
As the refrigerant passes through the valve orifice, its pressure is reduced and part of the refrigerant turns into （）.
A
liquid
B
oily mixture
C
emulsion
D
vapor
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单选题As the refrigerant passes through the valve orifice, its pressure is reduced and part of the refrigerant turns into （）.A
liquidB
oily mixtureC
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单选题In a compression refrigeration plant the refrigerant flows from the expansion valve and through the （） where it absorbs heat from the space being cooled and becomes a gas or vapor.A
compressorB
condenserC
throttle valveD
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openB
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单选题A pressure drop through the refrigerant liquid line may cause （）.A
solenoid valve to seizeB
compressor to huntC
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单选题The only means of removing the latent heat of condensation from a refrigerant in the normal refrigeration cycle is by （）.A
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condensing refrigerant in the system condenserC
passing the gaseous refrigerant through the heat interchanger on the suction side of the compressorD
maintaining a high pressure on the systems receiver
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单选题After passing through the expansion valve the refrigerant should be in the state of （）.A
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a pre-tensioned springC
any springD
upstream pressure
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