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1·The result shows that average absorption coefficient and noise reduction coefficient separately equal to 0.

结果表明材料的平均吸声系数和降噪系数分别达0。

2·The result shows that average absorption coefficient and noise reduction coefficient separately equal to0.58and0.60 and fine property of sound absorption at middle-low frequency.

结果表明材料的平均吸声系数和降噪系数分别达0。58和0。60，且材料的中低频吸声性能优良。