短语词组短语Rarefaction gas 稀薄气体Rarefaction curves 生成稀释曲线rarefaction fan 稀疏翼gas rarefaction 稀薄气体Rarefaction Treatment 疏化处理rarefaction parameter 稀薄参数rarefaction defect 疏松缺陷rarefaction ŕ 稀疏酌rarefaction wave 稀疏波；膨胀波；余波 返回 rarefaction