Tambov State University

About: Tambov State University is a education organization based out in Tambov, Russia. It is known for research contribution in the topics: Magnetic field & Nanoindentation. The organization has 696 authors who have published 845 publications receiving 4540 citations. The organization is also known as: G. R. Derzhavin State University.

Nanoindentation and mechanical properties of solids in submicrovolumes, thin near-surface layers, and films: A Review

Abstract: This paper presents a review devoted to the specific mechanical behavior of thin near-surface layers of various solids, materials, films, and multilayer coatings under local loading. Analysis is made of the principles, techniques, and instruments used for testing and determining mechanical properties of materials on a nanoscale, which, in recent years, have found a wide application under the general name “nanoindentation.” Information capabilities of this large and multifunctional family of methods employed for mechanical tests are discussed. Different aspects and specific features of the behavior of solids under severely constrained deformation caused by the local application of a microload to the surface of the test object are considered. Special attention is focused on the physical mechanisms of deformation and fracture under these conditions.

Magnetoplastic effects in solids

Abstract: This paper is an overview of the studies into the effect of weak magnetic fields on the structure and mechanical properties of nonmagnetic solids of various nature (ionic, covalent, molecular, and metallic crystals, polymers, etc.). The various effects and aftereffects initiated by static, pulsed, and microwave magnetic fields that have been discovered over the past 15 years are classified and critically analyzed. The thermodynamic and kinetic aspects of the magnetic-field sensitivity of real solids with structural defects containing paramagnetic centers (electrons, holes, radicals, excitons, etc.) are discussed. Possible mechanisms for the effect of a weak magnetic field on the defect structure of crystals are considered. Special attention is given to the most developed chemical-physical theory of spin-dependent reactions between mobile particles and unpaired electrons. Interpretation of magnetoplastic effects is proposed in terms of the spin, electron, molecular, and dislocation dynamics of the complex multistage processes initiated by a magnetic field in a system of metastable structural defects.

Sociocultural Strategies for a Dialogue of Cultures

Abstract: There is often a lack of learner opportunity for beyond-the-classroom interaction in school foreign language programs. This lack of opportunity places learners at considerable disadvantage when confronted with the inevitable psychological, linguistic, and sociocultural obstacles in second language communication (Savignon, 1972, 1983, 1997; Sysoyev, 1999a, 2001). In this article, we report the findings of a study that attempted to operationalize the concept of sociocultural competence for classroom learners and explore the benefit to learners of explicit training in strategies for coping with certain social and cultural situations. The goal of our study was to promote learners' sociocultural competence with a view to preparing them for a dialogue of cultures (Bakhtin, 1981, 1986; Bibler, 1991) essential to intercultural communication. Our report includes 3 sections: (a) a taxonomy of sociocultural strategies, (b) the description of a method of explicit strategy training developed for use in a Russian high school English as a foreign language (EFL) program, and (c) the outcome of an experimental program in explicit instruction in sociocultural strategies with a class of 11th grade EFL learners.

Morphology diagram of nonequilibrium patterns of ice crystals growing in supercooled water

Abstract: The morphology diagram of ice crystal patterns, which grow freely in a supercooled water is obtained experimentally in a “supercooling-tip velocity” phase space. This diagram classifies eight nonequilibrium macroscopic structures growing in the supercooling temperature region of heterogeneous nucleation of ice in pure water at atmospheric pressure. We found different kinds of morphology transitions between structures such as the first order, continuous, and the fork-like bifurcation transitions. It was shown that the nonequilibrium patterns exhibit various growing behaviours such as tip-splitting, tip-oscillating, and tip-stable modes. Supercoolings as large as 30°C can be achieved allowing ready access to both the diffusive and kinetic growth regimes. We found the supercooling ranges that correspond to kinetic regime of solidification in which under controlled conditions, for a given supercooling levels both fractal and nonfractal nonequilibrium growth patterns are reproducibly observed. The possible reasons for the competition between fractal and nonfractal structures growing in highly supercooled water are discussed.