Sound velocity dispersion in a solution with two critical points

The dispersion of the sound velocity in a solution with a region of stratification has been investigated experimentally in the frequency range from 2.6 MHz to 12 GHz. It is found that the dispersion of the sound velocity below the lower critical temperature of stratification reaches 22% and depends linearly to the temperature above the upper critical temperature of separation, the dispersion of the sound velocity is much smaller and has a different linear dependence on the temperature. Pis’ma Zh. éksp. Teor. Fiz. 64, No. 3, 166–168 (10 August 1996)