Pedersen P C, Ozcan H S
Ultrasound Med Biol. 1986 Jun;12(6):483-99. doi: 10.1016/0301-5629(86)90220-6.
In-vitro measurements have been carried out for the group velocity and the attenuation, in dB/cm, in cow lung tissue. The velocity and the attenuation were measured both as a function of air content, from 32 to 68%, and as a function of frequency, from 10 to 800 KHz. The group velocity was determined from measurement of the phase difference between the transmitted and incident acoustic signal while the attenuation was measured from the insertion loss with correction for the water-lung interface transmission losses. The measured group velocities indicate only a small degree of dispersion, but a strong dependence on air content. The attenuation is very high and exhibits strong frequency dependence, but weak air content dependence.
已对牛肺组织中的群速度和以分贝每厘米为单位的衰减进行了体外测量。速度和衰减分别作为空气含量（从32%到68%）以及频率（从10千赫兹到800千赫兹）的函数进行测量。群速度是通过测量透射和入射声信号之间的相位差来确定的，而衰减则是从插入损耗中测量，并对水 - 肺界面传输损耗进行校正。测量得到的群速度仅显示出很小程度的色散，但对空气含量有很强的依赖性。衰减非常高，表现出很强的频率依赖性，但对空气含量的依赖性较弱。
