Velocity−dispersion measurements in liquids between 3.3 MHz and 70.2 MHz

An improved differential phase−comparison method for the measurement of small changes in ultrasonic velocity is described. Velocity dispersion measurements can be carried out in the frequency range from 3.3 to 70.2 MHz; the relative accuracy is one part in 10⁵; only 12 cm³ of liquid are required. Results are presented for aqueous and organic solutions, which are in good agreement with known ultrasonic−absorption data.

Subject Classification: 35.24, 35.35.