Bilous O. Anomalous dynamic properties of binary solutions near their singular points

The thesis studies anomalous dependence of dynamic viscosity, effective absorption coefficient and sound propagation in different thermodynamics areas: phase transition, critical isotherm and isoconcentration. Here with binary solutions were studied near different singular points: phase separation of molecular, ion-molecular, ion-electronic binary solutions; and 1,2-propanol-water alcohols solutions near structural phase transition. The conducted acoustic research in a wide range of frequencies, (5-2500) MHz, for the first time allowed to propose the method of evaluation the contribution to effective sound absorption coefficient, which is connected with anomalous scattering of sound at concentrations fluctuations both near the critical point of phase separation and singular point of water-alcohol solutions. It is shown that H-bonds are responsible for the observed water and aqua structural phase transition. Temperature and concentration of water solutions singular point is defined as the intersection point of corresponding curves of temperature or concentration dependence of sound velocity and absorption coefficient. Increase of frequency as well as deviation from critical temperature or concentration brings the system to crossover or even hydrodynamic area.