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ACTIVITICAL EXISTING SUPPORTED MEMBERSHIP GROUPS
ACTIVITICAL EXISTING SUPPORTED MEMBERSHIP GROUPS
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机译:激活现有支持的会员组
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摘要
Water-impermeable, air-permeable membrane assemblies are described here. In some designs, the assemblies include a polymer membrane and at least one support or support layer. Certain assemblies are configured to allow acoustic impedance with a phase angle of +45degrees to -45 over a frequency range of 50 to 20.000 Hz.
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