单项选择题
A.rapidly B.by gravity C.through a standard orifice at a specified temperature D.at a rate of 60cc per second
When liquid reaches the compressor of a refrigeration s...
单项选择题When liquid reaches the compressor of a refrigeration system through the suction line, the condition is called （）.
A.flooding back B.superheating C.overflowing D.recycling
What is a function of the wearing rings used in most ce...
单项选择题What is a function of the wearing rings used in most centrifugal pumps?（）
A.Absorb erosion of high velocity discharge stream B.Seal pump shaft against entry of air C.Isolate the discharge side from the suction side D.Dampen the turbulent discharge flow
If air at 95℃ dry bulb temperature and 50% relative hum...
单项选择题If air at 95℃ dry bulb temperature and 50% relative humidity is conditioned to 75℃ dry bulb temperature and 50% relative humidity, it is an example of （）.
A.cooling only B.cooling and humidifying C.cooling and dehumidifying D.adiabatic cooling
