{HEAD ~ The gas} passes through the clearance between the third adsorption chamber and the partition II and {TAIL ~ the wall} of the under prop cover, the air inlet hole at the bottom of the under prop cover and evenly enters the second adsorption chamber and the first adsorption chamber filled with fine carbon particles 
passes through
{ HEAD ~ The gas } passes through the clearance between the third adsorption chamber and the partition II and { TAIL ~ the wall } of the under prop cover , the air inlet hole at the bottom of the under prop cover and evenly enters the second adsorption chamber and the first adsorption chamber filled with fine carbon particles
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