Uchenye Zapiski Zabaikalskogo Gosudarstvennogo Universiteta. Seriya Fizika, Matematika, Tehnika

12-23

Authors: Vladimir A. Tolpayev, Mariya A. Bondarenko, Vladimir V. Zaharov, Aleksandr M. Kravtsov, Musheg T. Petrosyants

A filtration law with kinematic correction for compressible fluid filtered in a porous medium is proposed. In the approximation of a plane wave, asymptotic solutions of the filtration equations were obtained in a closed form according to the Darcy law and according to the amended law with a kinematic correction. The illustrations are presented with graphs of the distribution of pressure and density of the flow of elastic energy in a stream of compressible fluid. The calculated estimates of the size of the filtration area are given for a practical example.

31-40

Authors: Svyatoslav Ye. Kholodovskii, Mariya G. Honina

Boundary value problems for the Poisson equation in a circle bounded by a weakly or strongly permeable on films are derived. Derived boundary conditions on films. The derived theorems of existence and uniqueness are proved. Solutions of boundary value problems are obtained in quadratures.

49-57

Authors: Sergey Ya. Berezin

The article deals with the theoretical provisions and experimental studies of contact stresses of plastic deformation by pressing a conical indenter. Empirical dependences of indicators of plastic properties in the form of contact stresses and yield stress on temperature, speed and degree of deformation for the main types of non-ferrous alloys are obtained. The method of analogy with the process of ball indenter indenta-tion is used to determine the degree of deformation during cone indenta-tion. The correlation of contact stresses with the Brinell hardness and relative weight parameters of the material is established. The nature of the influence of independent factors on the level of contact stresses is de-termined on the basis of empirical dependences.

67-74

Authors: Alexandr A. Gurulev

Due to the wide distribution of salt solutions in nature (in water bodies, in soils, in vegetation, etc.), an urgent task is to study the physicochemical processes taking place in them not only at positive temperatures, but also at negative ones. In the present work, the study of electrokinetic effects accompanying the crystallization of water-salt solutions was carried out using the example of sodium chloride solution. The measurements were performed with a monotonic change in the temperature of the sodium chloride solution at a rate of 0:28C/min with simultaneous measurement of the EMF arising between the platinum and copper electrodes, and temperature. As a result of the experiments, a correlation of the EMF signals in the sodium chloride solution with the process of crystallization of the sample at the eutectic temperature was found. At this moment, the magnitude of the EMF signal increases and then sharply tends to the minimum value. Also, by the rate of change of the sample temperature, it is possible to determine phase transitions in liquid and solid media. With joint thermometry and measurements of electric potentials, it is possible to study the features of the processes of formation and destruction of crystals in solutions.