Ufa, Russia

Bashkir State University is located in Ufa, Bashkortostan, Russia, founded in 1909, is among the top ten classical universities of Russia. Wikipedia.

Time filter

Source Type

Khasanov M.K.,Bashkir State University
Journal of Applied Mathematics and Mechanics | Year: 2017

On the basis of equations of the mechanics of multiphase media, a mathematical model of injection of carbon dioxide into a porous medium saturated with methane and its gas hydrate is constructed. The case is considered where on two moving frontal surfaces separating a porous stratum into three regions, boiling of carbon dioxide and replacement of methane by carbon dioxide gas in the initial gas hydrate take place. For the axially symmetric problem, self-similar solutions describing the pressure distribution in each of the three percolation regions are constructed. The dynamics of the two moving phase transition boundaries as a function of mass injection rate, the initial pressure, and permeability of the porous medium is investigated. It has been established that the extent of the region saturated with liquid carbon dioxide increases with growth of the injection rate and the initial pressure and lowering of the permeability, and the velocity of the front of methane replacement in the hydrate by carbon dioxide gas increases with increase in the injection rate and permeability and lowering of the initial pressure. It has been shown that boiling of carbon dioxide as a consequence of a corresponding decrease of its viscosity promotes acceleration of the front of methane replacement in the hydrate by carbon dioxide gas. © 2017 Elsevier Ltd.

Potapov A.A.,Bashkir State University | Garipova G.M.,Bashkir State University | Nandi K.K.,North Bengal University
Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics | Year: 2016

We revisit certain features of an assumed spherically symmetric perfect fluid dark matter halo in the light of the observed data of our galaxy, the Milky Way (MW). The idea is to apply the Faber-Visser approach of combined observations of rotation curves and lensing to a first post-Newtonian approximation to "measure" the equation of state ω(r) of the perfect fluid galactic halo. However, for the model considered here, no constraints from lensing are used as it will be sufficient to consider only the rotation curve observations. The lensing mass together with other masses will be just computed using recent data. Since the halo has attractive gravity, we shall impose the constraint that ω(r)≥0 for r≤RMW, where RMW~200 kpc is the adopted halo radius of our galaxy. The observed circular velocity ℓ (=2vc2/c02) from the flat rotation curve and a crucial adjustable parameter D appearing in the perfect fluid solution then yield different numerical ranges of ω(r). It is demonstrated that the computed observables such as the rotation curve mass, the lens mass, the post-Newtonian mass of our galaxy compare well with the recent mass data. We also calculate the Faber-Visser χ-factor, which is a measure of pressure content in the dark matter. Our analysis indicates that a range 0≤ω(r)≤2.8×10-7 for the perfect fluid dark matter can reasonably describe the attractive galactic halo. This is a strong constraint indicating a dust-like CDM halo (ω~0) supported also by CMB constraints. © 2015 The Authors.

Borisov D.,Bashkir State University | Cardone G.,University of Sannio
ESAIM - Control, Optimisation and Calculus of Variations | Year: 2011

We consider the Dirichlet Laplacian in a thin curved three-dimensional rod. The rod is finite. Its cross-section is constant and small, and rotates along the reference curve in an arbitrary way. We find a two-parametric set of the eigenvalues of such operator and construct their complete asymptotic expansions. We show that this two-parametric set contains any prescribed number of the first eigenvalues of the considered operator. We obtain the complete asymptotic expansions for the eigenfunctions associated with these first eigenvalues. © EDP Sciences, SMAI, 2010.

Borisov D.,Bashkir State University | Bunoiu R.,University of Lorraine | Cardone G.,University of Sannio
Zeitschrift fur Angewandte Mathematik und Physik | Year: 2013

We consider a magnetic Schrödinger operator in a planar infinite strip with frequently and non-periodically alternating Dirichlet and Robin boundary conditions. Assuming that the homogenized boundary condition is the Dirichlet or the Robin one, we establish the uniform resolvent convergence in various operator norms and we prove the estimates for the rates of convergence. It is shown that these estimates can be improved by using special boundary correctors. In the case of periodic alternation, pure Laplacian, and the homogenized Robin boundary condition, we construct two-terms asymptotics for the first band functions, as well as the complete asymptotics expansion (up to an exponentially small term) for the bottom of the band spectrum. © 2012 Springer Basel AG.

Sadovaya V.V.,Kazan Federal University | Khakhlova O.N.,Bashkir State University | Reznikov A.A.,Kharkiv National Automobile and Highway University
International Journal of Environmental and Science Education | Year: 2015

Thematic justification of the study is conditioned by the fact that in contemporary system of higher professional pedagogical education we can see serious drawbacks in training the future teachers for the methods of organizing leisure time activities and interacting with children. Therefore, this article studies the problem of future social teachers being professionally ready to organize children's leisure activities. Personal-activity and individual- creativity approaches were the leading in our research. As a result we have revealed the essence and content of social teacher’s professional activity, components of its professional readiness to organize the leisure activities of children and adolescents. We have shown technological and substantive aspects of professional training of future social workers such competence in the educational process of pedagogical high school. The material given here is of practical significance for specialists in the organization of children's leisure; for a system of higher education in organizing the special courses of future teachers training. © 2015 by iSER, International Society of Educational Research.

Kartak V.V.,Bashkir State University
Journal of Nonlinear Mathematical Physics | Year: 2011

Second order ordinary differential equations that possesses the constant invariant are investigated. Four basic types of these equations were found. For every type the complete list of nonequivalent equations is issued. As the examples the equivalence problem for the Painleve II equation, Painleve III equation with three zero parameters, Emden equations and for some other equations is solved. © 2011 B. Kruglikov.

Davletbaev A.Y.,Bashkir State University
Journal of Engineering Physics and Thermophysics | Year: 2012

Consideration is given to the problem on propagation of a pressure field in a low-permeability porous medium with two wells that are connected by a technogenic hydraulic fracture. The approximate numerical solution of this problem is obtained; an analysis of the influence of the above fracture on the system's parameters is made; responses of the pressure in a well are modeled. The inverse problem is solved with the numerical model developed, and the system's parameters are evaluated from the field data measured in the process of hydrodynamic investigation by the method of pressure interference testing. © 2012 Springer Science+Business Media New York.

One of the possible conceptions of historical and actual pedagogical works providing a higher processability in the organization of research in the spheres mentioned above is getting stated and proved in this article. The logic and structure of the pedagogical process in its modern sense makes up the basis of the conception. Within the proposed model such its components as aims, objectives, content, forms, methods, means, the achievement of the aim, results of the educational systems' activities, the evaluation of the achieved result and all the process as a whole have been marked out. Following the declared idea will let researchers logically and consistently reveal, analyze, generalize and extrapolate the historical and pedagogical experience into the modern educational theory and practice.

Golovina A.M.,Bashkir State University
Russian Journal of Mathematical Physics | Year: 2012

A multidimensional matrix operator of general form is considered, which need not be symmetric, with finitely many distant perturbations that are described by arbitrary abstract localized operators. We study the behavior of the resolvent of the perturbed operator as the distances between domains at which the perturbations are localized tend to infinity. An explicit formula for the resolvent of the perturbed operator is obtained; it is used to obtain a complete asymptotic expansion of the resolvent. © 2012 Pleiades Publishing, Ltd.

Zakirova V.G.,Kazan Federal University | Gaysina G.I.,Bashkir State University | Zhumabaeva A.,Kazakh National Pedagogical University
International Journal of Environmental and Science Education | Year: 2015

Relevance of the problem stated in the article, conditioned by the fact that the successful adaptation of orphans in a foster family requires specialized knowledge and skills, as well as the need of professional support. Therefore, this article aims at substantiation of the effectiveness of the developed pilot program psycho-pedagogical support of adaptation of orphans in a foster family. The leading method of this problem’s study is the experimental method aimed to identify the problems of the adopted children and to test the program of professional support of their adaptation. The authors present the program of the orphans’ adaptation support, which includes diagnostic, projective, correctional, rehabilitative, recovery and consulting parts. This program is aimed both at providing psychological and educational assistance to adopted children and foster parents, and the achievement of successful adaptation of orphans to new conditions in a foster family. © 2015 by iSER, International Society of Educational Research.

Loading Bashkir State University collaborators
Loading Bashkir State University collaborators