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The influence of a low axial temperature gradient on the growth of the Ge:Ga crystal by the vertical Bridgman technique was investigated. The axial temperature gradient of 3.3 K/cm is shown to provide conditions for polycrystalline growth of Ge:Ga crystals. The layers with the distances from 14 to 277 μm are found in the grown crystals with a concave of the solid-liquid interface. The motion of textolite particles in distilled water is visualized by the light cut method at different values of axial and radial temperature gradients. In the absence of the radial temperature gradient, no convection is observed when the axial temperature gradient increases from 0.1 to 6.5 K/cm. In this case, the particle motion velocity increases proportionally to the axial temperature gradient due to the occurrence of thermal diffusion. The convective flow appear in the liquid at the radial temperature gradient of 0.6 K/cm and an axial gradient above 0.1 K/cm.

An effective method has been developed for the operative control of the homogeneity of the distribution of electrophysical properties in semiconductor materials as measured by thermo-emf. This method is applicable to samples with predominantly one type of conductivity. In this case, it is possible to obtain qualitative and quantitative results of the concentration of charge carriers. It is shown that in the case of the mixed conductivity type, only a qualitative analysis of the concentration of charge carriers is possible, which, however, can also be useful and informative when studying the processes of doping semiconductor crystals.

The article is devoted to the key questions of distance interaction between students and teachers in Moodle. The purpose of the study is to determine the capabilities of the BigBlueButton module for organizing independent work of students and to describe the methodological aspects of distance interaction of a future bachelor in the course of study the disciplines in the field of "Pedagogical Education". The main research methods were the analysis of scientific literature devoted to the problems of organizing independent work of students and the use of modern information and communication technologies in education; the study of normative documentation related to the educational process at university; generalization of the experience of distance interaction between students and teachers and empirical research methods. As a result of the study, the authors described the main requirements for the independent work of students. The article defines the independent work and various classifications of the independent work of students. Special attention is paid to the classification according to the method of organization, namely individual form of the independent work of students, work in pairs, work in small groups, and group work. The features of a shared chat, shared notes, and a room for group work of the BigBlueButton module for organizing independent work of students are described. The paper considers methodological solutions for organizing various types of independent work of students in the BigBlueButton module. Specific examples of how independent work is organized based on the use of Internet services have been given.

The thermal conditions for the growth of Ge crystals with a diameter of 50 mm by the vertical Bridgman method in the case of low thermal-gravitational convection are studied using model experiments. Distilled water being hydrodynamically similar to the Ge melt is used as the model liquid. When modelling by means of the light cut method, it is established that mixture particles move along the heat flow direction from top to bottom. It is shown that an axial temperature gradient of 2 K/cm or more increases the contribution of thermal diffusion to mass transfer at a vertical flow rate of 0.09 mm/s or more. The numerical simulation of thermal convection in the Oberbeck–Boussinesq approximation confirms the absence of convection under the given thermal conditions. However, the deviation of the container axis from the vertical by 0.5° during the process of crystal growth contributes to the increase in the flow rates in the liquid phase up to 0.55 mm/s.

The paper examines the synchronic merger of vowels /o/ and /ω/ in Russian regional dialect of villages Kay and Juzhaki (Kirov Region, North East of European Russia). In particular, it attempts to answer the questions: What is the motivation for the sound change? How do mergers develop? What is the result of this phonological process? These problems are solved using phonological, acoustic and perception analyses.

Reports on dialectological expeditions of the Vinogradov Institute of Russian Language (Russian Academy of Sciences) in 2013 (ed. by A. V. Ter-Avanesova).Expedition to the village of Rogovatoje (Staryj Oskol district, Byelgorod region) (S. V. Dyachenko, I. A. Bukrinskaya, I. I. Isayev, O. Ye. Karmakova, A. V. Ter-Avanesova).Expedition to the village of Deulino (Ryazan region, Ryazan district) (S. V. Dyachenko, A. V. Malysheva).Expedition to the Verkhnekamskiy district, Kirov Region (T. N. Korobeynikova).Expedition to Bolivia (O. G. Rovnova).

Investigations of conditions for crystallization providing desirable modes of heat and mass transfer during terrestrial and space experiments have been carried out. They are necessary for semiconductor crystal growth with high homogeneity of properties using Ge doped with Ga. Mathematical simulation and experimental investigations of the influence of the intensity of convective flows on micro- and macrohomogeneity ofcrystals grown by the method of vertical directed crystallization have been carried out. It has been shown that, to achieve high homogeneity of crystal properties at growth under both terrestrial and space conditions, minimization of a radial temperature gradient and elimination of a free melt surface (Marangoni convection) are necessary.