Pressure Dependence of the Ultrasonic Absorption in Toluene and Hexane

Abstract

Ultrasonic absorption and sound speed have been measured in toluene and n-hexane in the pressure range 1–10 000 kg/cm2 at 30°C. In these Kneser-type liquids, for which the absorption may be attributed to thermal relaxational processes as well as to the dilatational and shear viscosities, various contributions to the absorption can be resolved by making specific assumptions about the ratio of the dilatational and shear viscosities. An attempt has been made to relate the thermal contribution to relevant theory.