


Vol 61, No 4 (2018)
- Year: 2018
- Articles: 25
- URL: https://bakhtiniada.ru/1064-8887/issue/view/14889
Anniversary Journal
Theory of a High-Voltage Pulse Discharge in a High-Pressure Gas: Hydrodynamic and Kinetic Approaches
Abstract
Comparative results of modeling of the phenomenon of a high-voltage discharge in nitrogen at atmospheric pressure based on two theoretical approaches: hydrodynamic and kinetic descriptions of electrons in discharge plasma are presented. The detailed spatiotemporal pattern of the development of coaxial gas-filled diode breakdown with formation of runaway electrons in it is described. It is demonstrated that the switching characteristics of the subnanosecond discharge are reliably modeled within the limits of both hydrodynamic and kinetic descriptions of electron components, whereas the parameters of runaway electrons can reliably be calculated only using the kinetic description.



Article
Regularities and Mechanisms of Formation of Submicro-, Nano-, and Ultrafine-Grained Structures and Mechanical Properties of Metals and Alloys Under Different Treatments
Abstract
An overview of our original studies and the results reported in the literature on the investigation of variations in structure, phase composition, mechanical and other properties of metallic materials under external impacts is made, including their high-pressure processing by large (severe) plastic and megaplastic deformation, explosion loading, and irradiation with ultra-short laser pulses.



Wave Diagnostics and Forcing
Abstract
Physical possibilities of remote diagnostics and manipulation with the state of the propagation medium by the methods of wave tomosynthesis are considered. This refers to the electromagnetic and acoustic waves as well as waves of other nature. Important are multi-position measurements with retention of phase information at each point of the medium that allows the technology of synthesizing a wide aperture with focusing to be implemented. Processing of wave projections of hidden objects makes it possible to restore their three-dimensional images. In this way, the effect of multiple wave re-reflections is reduced. In addition, the tomographic approach allows one to manipulate with the properties of the media being sounded. Thus, an increase in the radiation power at a chosen focusing point causes hyperthermia that can be used, for example, to treat oncological diseases. And creation of a minimum field and a preset phase distribution in certain regions of the medium opens the possibility of control over the motion of microparticles being trapped. The last circumstance is important, for example, for targeted delivery of medical preparations in medicine.



Averaging of the Equations of the Standard Cosmological Model over Rapid Oscillations: Influence of the Cosmological Term on the Mean Value of the Effective Barotropic Coefficient
Abstract
With the help of an applied software package written by the authors, we have averaged the effective total barotropic coefficient κ = (–λ + p)/(λ + ε) of the classical scalar field and the cosmological term and have shown that during cosmological evolution for sufficiently large values of the cosmological constant the Universe transitions from the inflationary stage to a nonrelativistic stage, and then, after a plateau, it transitions to a later inflationary stage.



Concerning the Paper by A. Einstein “Explanation of the Perihelion Motion of Mercury from the General Theory of Relativity”
Abstract
It is shown that in A. Einstein’s 1915 paper “Explanation of the perihelion motion of Mercury from the general theory of relativity” an error was actually incurred in the integration of the equation \( \phi =\left[1+\upalpha \left({\upalpha}_1+{\upalpha}_2\right)\right]\underset{\upalpha_1}{\overset{\upalpha_2}{\int }}\frac{dx}{\sqrt{-\left(x-{\upalpha}_1\right)\left(x-{\upalpha}_2\right)\left(1-\upalpha x\right)}} \), and in the result instead of \( \phi \approx \uppi \left[1+\frac{5}{4}\upalpha \left({\upalpha}_1+{\upalpha}_2\right)\right] \) (if we limit ourselves to first-order terms in the small quantity (α1 + α2)) the value \( \phi \approx \uppi \left[1+\frac{3}{4}\upalpha \left({\upalpha}_1+{\upalpha}_2\right)\right] \) was obtained, where α1 and α2 are the inverse values of the maximum and minimum distances of Mercury from the Sun, \( \upalpha =\frac{2G{m}_0}{c^2} \) is the gravitational radius, G is the gravitational constant, m0 is the mass of the Sun, c is the velocity of light (i.e., the Chinese mathematician Hua Di was actually right). And, as a result, for the precession of the orbit of Mercury in the gravitational field of a spherical Sun in the general theory of relativity (after 100 years) one obtains not ~43”, as A. Einstein obtained, but ~71.63”. Exactly this latter result is obtained by direct numerical modeling of the precession of the perihelion of Mercury’s orbit in the gravitational field of the Sun within the framework of the general theory of relativity if the fitting coefficient α in the equation of motion of Mercury (not to be confused with α in the above equations) is set equal to zero. The result \( \phi \approx \uppi \left[1+\frac{3}{4}\upalpha \left({\upalpha}_1+{\upalpha}_2\right)\right] \), obtained by A. Einstein if it is obtained, happens only upon integration of either the equation \( \phi =\left[1+\frac{\upalpha}{2}\left({\upalpha}_1+{\upalpha}_2\right)\right]\underset{\upalpha_1}{\overset{\upalpha_2}{\int }}\frac{dx}{\sqrt{-\left(x-{\upalpha}_1\right)\left(x-{\upalpha}_2\right)\left(1-\upalpha x\right)}} \) (if we also limit ourselves to first-order terms in the small quantity (α1 + α2)), i.e., in front of the integral in brackets the coefficient 1/2 should stand in front of the quantity α, or the equation \( \phi =\left[1+\upalpha \left({\upalpha}_1+{\upalpha}_2\right)\right]\underset{\upalpha_1}{\overset{\upalpha_2}{\int }}\frac{dx}{\sqrt{-\left(x-{\upalpha}_1\right)\left(x-{\upalpha}_2\right)\left(1-\upalpha x\right)}} \) (if we also limit ourselves to first-order terms in the small quantity (α1 + α2)), i.e., in the denominator under the differential in the integral, inside the square root\ a plus sign should stand in front of the quantity αx.



Possible New Astrophysical Effects of the Gravitational Interaction of Stationary Vortex Electric and Magnetic Fields
Abstract
Possible realistic means of formation of wormholes are considered and investigated. As a realization of such, it is proposed to apply self-gravitating physical fields having a vortex character. In the present paper, we consider using a stationary vortex electric field. We show that within the framework of Einstein’s theory of gravitation, a self-gravitating vortex electric field can induce the formation of wormholes. We also show that the combined use of a vortex electric field and a vortex magnetic field improves the traversability of the obtained wormholes since their throat radii are significantly increased.



Emission of a Neutrino Pair During Transitions of an Electron in the Field of the Nucleus of a Hydrogen-Like Atom in One Spatial Dimension
Abstract
The Dirac equation for a particle – an electron with negative charge equal in magnitude to the elementary charge e1 in spacetime with one spatial dimension denoted as the z axis and in the field of a point-like charge (Ze1) – the nucleus – with the one-dimensional potential φ1 = – (Ze1) |z| (a one-dimensional hydrogen-like atom) is solved. The two-component wave function and the quantum values of the energy are expressed in terms of the Airy function and its zeros. Using the contact Lagrangian of the weak interaction with Fermi constant G1 = g1ħc in such a space, where g1 is some number, the probability of emission per unit time of a neutrino pair (Ze1)*→(Ze1) + νν– by the one-dimensional hydrogen-like atom, which turns out to be proportional to the square of the mass, is found. Prospects for the realization of the considered effect and its possible significance at various stages of the evolution of the Universe are discussed.



The Hubble Constant of Large-Scale Substances and Cosmic Bodies
Abstract
A result of calculation of the topological properties of the Universe and its large-scale substances is presented. An equation for calculating values of the Hubble constant of the substances of the Universe, and of the Universe and the Galaxy, Sun, and Earth has been obtained for the first time. Their age and the time of one full cycle and of five cycles of expansion and compression of the Universe are calculated. A new hypothesis about the formation of the relic background of the Universe is proposed. The infinity of its evolution in time is proven.



Special Features of the Joint Influence of Low-Order Secular Resonances and Light Pressure on the Motion of Near-Earth Space Objects
Abstract
Joint influence of secular resonances and light pressure on the long-term orbital evolution of objects in the near-earth space bounded by the semi-major axes of orbits from 15000 to 45000 km is considered. The orbital evolution of each object is considered for three area-to-mass ratios: 0.001, 1, and 10 m2/kg. Special attention is given to a search for resonances whose influence increases the eccentricities of near-earth space object orbits and to their joint analysis with the influence of the light pressure force on the object dynamics.



Investigation of a Method for Improving Asteroid Orbits Based on Replacement of Observations with Their Simulated Values
Abstract
A method for improving asteroid orbits by gradual replacement of observations with their simulated values is considered. The method consists in successive rejection from processing of observations with maximal residuals and replacement of these observations with their values calculated in the last iteration of the process of orbit improvement. In addition, the traditional method of gradual rejection of observations with maximal residuals that does not preserve any information on these observations is considered. The accuracies of the methods are compared for a number of improvements of orbits of asteroids Nos. 115489 and 179699 from observations of their separate oppositions and pairs of oppositions. It is demonstrated that the method of replacement of observations with simulated values yields as a whole more exact results in comparison with the traditional methods of observation rejection.



Physical Processes of SiO2 Spherical Particle Formation in Thermal Plasma Flow
Abstract
The paper presents the structural investigations of hollow, spherical powder obtained from the natural siliceous material using the thermal plasma treatment. Experiments show that the obtained hollow SiO2 particles have almost an ideal spherical shape. Based on the analysis of numerical calculations, thermochemical modeling and results of in-situ experiments, we propose a physical model of formation of hollow, spherical particles produced from agglomerated powder using the thermal plasma flow.



Stability of Homogenous Plastic Deformation in Alloy Single Crystals with L12 Structure Under Tension and Compression
Abstract
The paper studies the loss of stability of high-temperature, homogenous plastic deformation of alloys with L12 structure during the super-localization process. Using methods of mathematical simulation, a joint effect of geometric and physical factors on the stability loss of plastic deformation is analyzed under the tensile and compressive stresses. The properties of elements of the deformable medium are detected, at which the macroscale loss of stability is observed in relation to homogenous plastic deformation. It is found that super-localized plastic compressive deformation occurs when physical softening is ahead of the geometric strengthening. Under the tensile stress, the loss of stability of homogenous plastic deformation always occurs due to necking because the geometric softening begins before physical.



Residual Stresses Induced by Elastoplastic Unloading in a Tube Made of Dispersion-Hardened Alloy
Abstract
The paper carries out research into elastoplastic unloading using methods of plasticity theory and solid mechanics. Residual stresses are measured in a heavy-walled tube made from a dispersion-hardened copper alloy. It is shown that residual radial stresses are insignificant after the unloading and do not exceed 0.5 MPa. When the ultimate plastic strength is achieved, the amount of residual tangential and axial stresses is almost 17% of the ultimate shear stress.



High-Temperature Plasma Sintering of the Mixture of Different Fractions of the Plasmadynamic Synthesis Product
Abstract
The paper examines a technique for producing metal-cutting ceramics from the plasmadynamic synthesis product using the spark plasma sintering technology. It studies the dependence of physico-mechanical properties of ceramics on the mixture parameters. Increase in bulk density and effect produced by this increase are well observed when comparing the sintering process curves. Movable die displacement for non-activated powder is 3.5 mm, while powder activation allowed reaching the 1.75 mm displacement, other conditions being equal. Hardness of produced materials measured by Vickers method was 21 GPa for non-activated powder and 17 GPa for activated powder at relative densities of sintered ceramic workpieces in relation to osbornite monocrystal of 92% and 93.5% respectively. Significant increase in density of the sintered body is ensured mainly by elimination of the raw material agglomeration.



Structural and Morphological Features of TiNi-Based Powder Manufactured by the Method of Hybrid-Calcium Reduction
Abstract
An investigation of the structural features and surface morphology of a PV-N55T45 TiNi-based powder manufactured by the method of hybrid-calcium reduction is performed. The TiNi intermetallic compound is found in a two-phase state – B2 and В19′, and the following secondary phases are revealed: Ti2Ni, Ti4Ni2(О, N, С), TiNi3, and Ti3Ni4. It is observed that TiNi-based powder has dual – compact and spongy – morphology. The compact powder particles consist of oval coarse grains of TiNi separated by a massive Ti2Ni interlayer. In the spongy particles, in contrast to the compact ones, the TiNi-phase prevails in the form of a single conglomerate of fine grains measuring 10–20 μm. In the Ni-enriched regions of the TiNi matrix the B19′-martensite is observed in multiple structural-morphological variants. In the compact particles the martensite structure represents orthogonal twin plates having different orientations within one grain. In the spongy particles, there is a different type of the martensite structure with multiple crystals of the B19′-martensite with the pyramidal lath morphology. On the surface of certain particles there is terraced relief formed due to bulk diffusion of atoms, surface diffusion of adatoms, and their interaction with the substrate defects.



Surface Current Approximation in Certain Problems of the Classical Theory of Superconductivity
Abstract
The problems of the behavior of superconducting infinite plane-parallel plate and cylinder in an external magnetic field are solved in the approximation of the model of surface currents. The latter, in contrast to the conventional notation, enter as the currents of superconducting electrons into the boundary conditions for the magnetic induction. Surface currents are understood as the volumetric current flowing in the thickness of the near-surface layer, which is associated with the thickness of the London penetration depth of the field and currents into the thickness of the superconductor. It is shown that in this case, a jump in the magnetic quantities occurs at this thickness. The calculated average magnetization of the magnet is reduced to the strength of the external field. The proportionality coefficient, which is reasonable to call the mean magnetic susceptibility, turns out to be not exactly equal to –1, but has a slightly less value, because the field does not weaken immediately. The possibilities of experimental verification of the obtained effect are discussed.



Phase Equilibrium and Critical Phenomena in the n-Pentan–Water and n-Hexane–Water Systems at High Temperatures and Pressures
Abstract
PVTx-properties of the H2O – n-C5H12 and H2O – n-C6H14 mixtures are measured in the temperature range 303-680 K at pressures up to 60 MPa. The measurements were carried out along 265 liquid and vapor isochors in a density range of 63-713 kg/m3. The measurements were performed for 15 concentrations between 0.110 and 0.987 mole fractions of H2O for the C5H12 mixtures and for 11 concentrations between 0.166 and 0.977 mole fractions of H2O for the C6H14 mixtures. The temperatures and pressures on the three-phase and two-phase boundary curves were obtained for the mixtures from isochors using the kink or inflection method. The data for the critical parameters of the upper and lower branches of the critical curves were obtained from the boundary curves by the method of rectilinear diameter. The measured three-phase data were used to estimate the value of the upper final critical point.



Study of the Quantitative Absorption Characteristics in the υ2 Band of the 34SO2 Molecule
Abstract
High-resolution infrared spectrum of the 34SO2 molecule is recorded with a Bruker IFS-120 HR Fourier spectrometer. More than 3000 transitions (with Jmax = 60 and \( {K}_a^{\mathrm{max}} \) = 19) are assigned as a result of analysis. The Watson Hamiltonian is used as a theoretical model. The experimental intensities of 700 single rovibrational lines of the υ2 band are analyzed.



On Gravitational Nonmetricity Plane Waves in an Affine-Metric Space



Elementary Particle Physics and Field Theory
Singular Solutions of Clairaut Equations
Abstract
A relationship is established between singular solutions of the Clairaut equation in the theory of ordinary differential equations and singular solutions of the Clairaut equation in the theory of partial differential equations. It is shown that exact relationships exist between Legendre transformations in classical mechanics and Clairaut equations.



Plasma Physics
Instability Increments of Stimulated Mandelshtam–Brillouin Scattering in a Bounded Region with Allowance for Collisions
Abstract
The problem of Mandelstam–Brillouin scattering in the region bounded in the direction of pump wave propagation and infinite in the transverse direction is considered. Such situations can arise, for example, in plasma heating or diagnostic problems. Since the time of scattered radiation escape for the examined geometry upon scattering at a certain angle increases substantially, this effect compensates for a decrease in the nonlinear feedback coefficient upon oblique scattering and leads to instability development. Since the convective losses at scattering angles close to π/2 are small, collisional absorption of waves plays an important role in this case. The instability increments are calculated taking into account not only the convective losses, but also the collisional wave attenuation.



Condensed-State Physics
The Influence of Modification on Crystal Lattice Stability of Austenite in Stainless Steel
Abstract
Using the methods of electron diffraction microscopy and X-ray diffraction analysis, the influence of alloying of the austenitic steel, Grade 110H13, with chromium and vanadium, as well as high-melting, ultrafine-grained TiO2, ZrO2 powders and Na3AlF6 cryolite on its structural-phase state and microstructure is investigated. It is shown that the matrix of non-modified steel is completely austenitic and consists of an iron-based solid solution and the interstitial (C, N, O and other) and substitutional (Cr, V and other) atoms simultaneously. Alloying with chromium and vanadium changes neither its phase composition nor defect structure, while alloy modification results in qualitatively new structural features: γ → ε-transformation, high-intensity microtwinning, defect structure changes, and a sharp increase in the scalar dislocation density. The features of the deformation-induced microtwinning and ε-martensite plates identified in the modified steel promote revealing additional microtwin systems in the matrix γ-phase, which result in structural changes making it possible to classify it as a γ′-phase. It is found out that an introduction of modifying additions gives rise to the following sequence of structural-phase transformations: γ→γ′→(γ′ +ε). The experimental data obtained demonstrate that as a result of modification the crystal lattice transits into a low-stability state. This transition is accompanied by marked structural-phase changes consisting in the formation of several microtwin systems and γ → ε-transformation. These structural-phase changes in the modified steel are due to the crystal-lattice transition into the low-stability state, followed by new structural-phase alterations.



Physics of Semiconductors and Dielectrics
Nonlinear Polarization Effects in Dielectrics with Hydrogen Bonds
Abstract
Using quasiclassical kinetic theory, nonlinear phenomena under the formation of space-charge polarization in crystals with hydrogen bonds (HBC) are investigated. From the solution of the nonlinear system of Fokker-Planck and Poisson equations with blocking electrodes, it is established that for the mathematical description of the relaxation polarization in HBCs in weak fields (100-1000 kV/m) and at high temperatures (T> 350 K), it is sufficient to use a linear approximation of perturbation theory. Theoretically, it was found that at the first odd frequency of the alternating field, nonlinear effects caused by the interaction of relaxation modes of various frequency orders start to appear. The diffusion and mobility coefficients are calculated taking into account both mechanisms of the protons transitions (thermally activated and tunneling transitions) through a parabolic potential barrier. A recurrence expression is constructed for calculating complex amplitudes of relaxation modes generated at an arbitrary frequency (multiple to the fundamental frequency) of the alternating field in an arbitrary approximation of perturbation theory. The proposed scheme for solving the kinetic equation can be applied to other crystals with ionic conductivity similar to HBCs in the type and properties of the crystal lattice.



Optics and Spectroscopy
Study of the Absorption Characteristics of Transitions in the HOT 2υ2–υ2 Band of the 34SO2 Molecule
Abstract
The absorption coefficient of the rovibrational 2υ2–υ2 band of the 34SO2 molecule localized in the region 350–850 cm–1 is studied for the first time. An analysis of the above-mentioned band allows positions of the rovibrational lines and quantitative values of the absorption coefficients to be determined.



Brief Communications
Special Features of the Transverse Relaxation Time Distributions of NMR-Protons for Different Measurement Methods


