If the head pressure of a reciprocating refrigeration compressor is excessive, （）.
In its simplest form the pressure reducing valve is opened or closed by （） which is balanced by the downstream pressure acting on a diaphragm.
The （） is a crystal which, under pressure, produces an electric current which varies with the pressure.
The pressure head of a pump is given in the unit of （）.
The weather is often（）in a high-pressure area.
The atmosphere in the vicinity of a high pressure area is called a(n)（）.
The device used for low-pressure control and high-pressure cutout on a compressor is called （）.
A decrease in barometric pressure is associated with all of the following except（）.
Pressure gradient is a measure of（）.
Either a low injection pressure or a leakage of piston rings is able to lead （）.
Compared to a low pressure system，generally the air in a high is（）.
If a refrigeration compressor is short cycling on high head pressure, you should （）.
In a vacuum distillation system, the case is the higher the pressure, （）.
The gauge pressure inside a container is -0~5kg/cm2, then what is the absolute pressure exerted to the inside surface of thin container?（）
In a compression refrigeration plant the refrigerant is under low pressure in the （） and under high pressure in the （）.
Low compression pressure in a diesel engine is caused by（）
The vapor pressure of a gas is the pressure necessary to keep it in a(n)（）.
When normal operating pressure is applied to the hydraulic oil used in a high-pressure system, the oil （）.
On the pole side of the trade wind belt，there is an area of high pressure with weak pressure gradients and light，variable winds. This area is called the（）.
The pressure head of a water pump is given in the unit of （）.
A（）is created by a pressure gradient or slope in the water level.
In reading a weather map，closely spaced pressure gradient lines would indicate（）.
You blood pressure is a little high. 译成：
A generally circular low pressure area is called a (n) ______.
