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。
2
Sound absorbing coefficient was only 0.115.
而制品的吸声系数仅为0 . 115。
3
In the case of high frequencies, the sound reflection coefficient at sedimentary layer surface is simplified.