It is prevented by controlling the relative humidity of the circulating air and the temperature of the air.

控制循环空气的相对湿度和空气的温度可防止表面硬化的出现。

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BLOWER, an electrically operated fan for circulating air.

鼓风机，用来使空气循环的电动风扇。

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The circulating air system and parallel multiple sifting covers were used in QFZ cleaning-grading machine, which could be favorable for increasing throughput and reducing contamination.

Q FZ清理分级机采用循环风系统和并行的多层筛面，有利于提高产量并减少污染。

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There were crying babies, screaming customers, non-circulating air and way too much stress.

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The wind gains strength from the thermal energy of the ocean, eventually condensing vapors and circulating air fast enough to form high-speed wind and heavy rain.

CNN: graphic

Some experts believe that you also get circulating air patterns in the atmosphere above the boundary between the water and the land and this can initiate thunderstorms and showers.

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