Moscow State University of Mechanical Engineering

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Vyazmin A.V.,Moscow State University of Mechanical Engineering | Sorokin V.G.,Moscow State Technical University
Journal of Physics: Conference Series | Year: 2017

We consider nonlinear delay differential equations of hyperbolic type, including equations with varying transfer coefficients and varying delays. The equations contain one or two arbitrary functions of a single argument. We present new classes of exact generalized and functional separable solutions. All the solutions involve free parameters and can be suitable for solving certain model problems as well as testing numerical and approximate analytical methods for similar and more complex nonlinear differential-difference equations. © Published under licence by IOP Publishing Ltd.


Pervov V.S.,RAS Kurnakov Institute of General and Inorganic Chemistry | Zotova A.E.,Moscow State University of Mechanical Engineering
ChemPhysChem | Year: 2013

In this study, some features that distinguish inorganic supramolecular host-guest objects from traditional architectures are considered. Crystalline inorganic supramolecular structures are the basis for the development of new functional materials. Here, the possible changes in the mechanism of crystalline inorganic supramolecular structure self-organization at high interaction potentials are discussed. The cases of changes in the host structures and corresponding changes in the charge states under guest intercalation, as well as their impact on phase stability and stoichiometry are considered. It was demonstrated that the deviation from the geometrical and topological complementarity conditions may be due to the additional energy gain from forming inorganic supramolecular structures. It has been assumed that molecular recognition principles can be employed for the development of physicochemical analysis and interpretation of metastable states in inorganic crystalline alloys. Refurbishing of a concept: Possible deviations from the geometrical and topological complementarity conditions and changes in the mechanism of crystalline inorganic supramolecular structures self-organization at high interaction potentials are discussed. It is assumed that the molecular recognition principle can be used in physicochemical analysis for interpretation of metastable states in inorganic systems. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Dragunov S.S.,Moscow State University of Mechanical Engineering
2015 5th International Workshop on Computer Science and Engineering: Information Processing and Control Engineering, WCSE 2015-IPCE | Year: 2015

This article is devoted to answering the question of what should be the valve timing of the internal combustion engine in the future.


Lugantsev L.D.,Moscow State University of Mechanical Engineering
Chemical and Petroleum Engineering | Year: 2016

A method and algorithm for use in computer analysis of the carrying capacity and remaining life of composite shell structures that function under the conditions of thermomechanical and corrosion effects are set forth. © 2016 Springer Science+Business Media New York


Skobelev V.V.,Moscow State University of Mechanical Engineering
Journal of Experimental and Theoretical Physics | Year: 2016

A solution of the Dirac equation for an electron in the field of a point nucleus (Ze) has been obtained as an eigenfunction of the Schrödinger Hamiltonian and the spin projection operator Σ3. With the use of this solution, the probability W(ν) of the emission of a neutrino per unit time from a hydrogen-like atom, (Formula presented.) , has been calculated for the first time in the first order of the parameter Ze ≪ 1. The probability W(ν) appears to be rather small, and the corresponding lifetime τ(ν) = [W(ν)]–1 is much larger than the age of the Universe; correspondingly, this process cannot affect the balance of low-energy neutrinos. The smallness of W(ν) is due not only to the presence of the obvious “weak” factor (Gmp 2)2(m/mp)4 in the expression for W(ν), but also primarily to the “electromagnetic” factor (Zα)12, which can be revealed only in a particular calculation. It has been argued within quantum electrodynamics with the mentioned wavefunctions that photon emission, (Ze)* → (Ze) + γ, can be absent (analysis of photon emission requires the further development of the method), whereas axion emission, (Ze)* → (Ze) + a, can occur, although the last two effects have not been considered in detail. © 2016, Pleiades Publishing, Inc.


A solution of the Dirac equation for an electron in the field of a point nucleus (Ze), expressed in terms of an eigenfunction of the operator of the spin projection onto the third axis and the corresponding solution of the Schrödinger equation is derived. This solution is suitable for practical calculations. On the basis of this solution, using ordinary methods of QED and field theory, general principles for the emission of photons, axions, and neutrinos (Ze)*→(Ze)+γ,a,vv¯ by a hydrogen-like atom are formulated which take into account the spin state of the electron and, in the case of photons, their polarization. This range of questions pertaining to a comparative characteristic of processes of emission of massless or almost massless particles has, to this day, not been discussed from this point of view in the literature. Selection rules for γ, a, vv¯ emission processes are also obtained, where for axions and neutrinos they coincide with the existing selection rules in the literature ∆m = 0,±1; with ∆l = ±1 pertaining to photons, but for photon emission a few of them do in fact differ from them with the hypothesis of odd values of ∆l, not established by us and additional to the usual values ∆l = ±1 of variation of the azimuthal quantum number l due to the appearance of “new” integrals over the spherical angle θ for ∆m = ±1, where for ∆m = 0, as before, ∆l = ±1. Moreover, the dependence of the amplitude of the photon emission process on the quantum numbers is in principle different than in the previously adopted approach to the problem although the lifetime in the excited state for small values of the quantum numbers coincides in order of magnitude with the accepted value ~10–9 s. © 2016, Springer Science+Business Media New York.


Polyanin A.D.,Russian Academy of Sciences | Vyazmin A.V.,Moscow State University of Mechanical Engineering
Theoretical Foundations of Chemical Engineering | Year: 2013

Differential-difference heat conduction and diffusion models and equations with a finite relaxation time are described that give a finite disturbance propagation rate. The modified Biot-Fourier law with delay is used for the heat flux, which leads to the differential-difference heat-conduction equation ∂T/∂t+τ = aΔ T, where the left-hand side is calculated at t + τ (τ is the relaxation time) and the right-hand side is calculated, as usual, at t (without a time shift). At τ = 0, the differential-difference heat-conduction equation turns into the classical parabolic heat-conduction equation; if the left-hand side is expanded into a series in τ and two main terms of expansion are retained, we obtain the Cattaneo-Vernotte hyperbolic heat-conduction equation. An exact solution to the differential-difference heat-conduction equation is derived for a one-dimensional problem without the initial conditions with an arbitrary periodic boundary condition. The approximate solution is constructed to the general three-dimensional initial-boundary value problem of heat propagation with a finite relaxation time in a bounded domain with arbitrary initial heat distribution and the boundary condition of the third kind. It is shown that the differential-difference model makes it possible to derive the Oldroyd-type differential heat-conduction model. © 2013 Pleiades Publishing, Ltd.


Generalov M.B.,Moscow State University of Mechanical Engineering
Theoretical Foundations of Chemical Engineering | Year: 2013

The mechanism of structure formation is proposed in the crystallization of droplets of binary eutectic solutions in cryogenic liquids. Theoretical relationships are derived for calculating the rate of crystallite growth and the size of nanocrystals that form. Calculated values of the size of forming nanocrystals are compared with the experimental data. © 2013 Pleiades Publishing, Ltd.


Kadymov V.,Moscow State University of Mechanical Engineering
Mathematical Methods in the Applied Sciences | Year: 2015

The process of flow of a thin plastic layer enclosed between two approaching surfaces of the tool bodies is considered. The new results of theoretical and experimental researches are presented. Copyright © 2015 John Wiley & Sons, Ltd.


Aleksandrovich G.E.,Moscow State University of Mechanical Engineering
Ecology, Environment and Conservation | Year: 2016

Heavy metals are priority pollutants soil of cities, for example in Moscow the priority pollutants are zinc, lead, copper. The purpose of this study was to assess phytotoxicity of zinc on urban plants. The average zinc content in Moscow is 118 mg/kg, but the official data on soil pollution in Moscow are controversial due to mosaic of soils. In some areas there is an excess 1,04-3,1 times of approximate permissible concentration, which is 220 mg/kg. The object of our study was to lawn grasses and flowering plants. The degree of phytotoxicity was assessed by shoot growth of urban plants on filter paper placed in Petri dishes, as well as by sowing in soil, containing zinc. Zinc has an adverse effect even at relatively low concentrations on plants. Plants preserved decorative qualities when zinc concentrations in soil were less maximum permissible concentration (MPC) (MPC-100 mg/kg), growth inhibition was 20-30 %, depending on the plant species. Thus, zinc is the limiting factor for many ornamental plants, concentrations below about approximate permissible concentration. Copyright © EM International.

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