Vol 61, No 1 (2016)

The ionization constant of water K_w (or pH) is currently determined on the proton conductivity σ₀ which is measured at frequencies lower than 10⁷ Hz. We develop the idea that the high frequency conductivity σ_∞ (~10¹¹ Hz), rather than σ₀ represents a net proton dynamics in water. We count the concentration c of the H₃O⁺ and OH^– ions from σ_∞ to find c to be not dependent on temperature. We conclude that spontaneous ionization of H₂O molecules is not essential in water electrodynamics; the common K_w reflects the thermoactivation of the H₃O⁺ and OH^– ions from the potential of their interaction; the lifetime of a target water molecule does not exceed parts of nanosecond.

In this paper, the definition and description of vibrational diffusion (gradient) segregation of the bulk materials have been provided. The results of the experimental studies of this kind of segregation are described. This technique can be very useful for creation of entirely new high effective machines for granular separation. The results of theoretical investigation are presented. In this investigation, the diffusion equation, in which random and deterministic parameters are taken into consideration, has been used.

The effect of all-round isothermal forging on the structure and mechanical properties of low-carbon steel 12GBA is investigated.

A three-dimensional unsteady model of filmwise vapor condensation on a curved surface that takes into account the mass forces, the surface tension, and the friction on the surface of the condensate film is developed. This model generalizes the previous models of the filmwise vapor condensation. An evolution equation is derived for a condensate-layer thickness. Numerical algorithms are developed for solving the evolution equation. The condensation of ethanol vapor moving in a round tube is calculated. The effect of the tube diameter on the intensity of condensation is analyzed.

The Debye-Huckel approximation is generalized to the case of two-phase flows. A one-dimensional steady solution describing electroosmotic flow is found, and, for the first time, its linear stability is investigated analytically.

The force acting on particles or liquid droplets located in pores in the wave field is investigated in dependence on the wave frequency and the distances from the source.

Studies of galaxy clusters enable the evolution of the Universe at various stages of its life to be traced. The luminosities, sizes, temperatures, and masses of clusters are measured during their observations. Clusters are bound by gravitation with the universal constant G into a single whole. All these quantities are defined by three units of measurement: mass, length, and time. Therefore, there are two dimensionless parameters in the system usually called similarity parameters. One of them is the virial ratio of the potential and kinetic energies.