SovietRxiv · Open Access in English
Rediscovering the Soviet scientific archive, in English
25357 full-text translations 14926 English PDFs 22539 abstracts
Showing 50 of 25357 papers
The paper develops a generalized Hartree-Fock treatment for a nonideal Bose gas at temperatures well below the critical temperature, using one-particle two-time temperature Green functions with anomalous averages included. It argues that the standard Hartree-Fock closure produces an unphysical gap i…
This paper examines the time dependence of the electron and ion current fractions in the near-cathode region of an arc discharge, focusing on the development of a cathode spot. Using a nonstationary diffusion model with ion production by electron-impact ionization near the cathode, the authors deriv…
This paper studies when a subspace of a countable inductive limit of locally convex spaces is itself determined by the induced inductive system, either at the level of duals or topologically. It introduces conditions M0 and M for inductive limits and proves necessary and sufficient criteria for prop…
This note generalizes Craig’s theorem on the independence of quadratic forms in independent standard normal variables. It considers a quadratic polynomial Q and an arbitrary polynomial statistic P of a multivariate normal vector, and proves that P and Q are independent if and only if an orthogonal c…
This paper examines the kinetic theory of gases composed of nonspherical rigid molecules with rotational degrees of freedom, focusing on the mathematical structure of the corresponding Boltzmann-type equation. It derives the kinetic equation for rigid-body interactions as a limiting case of smooth r…
This study examines the evaporation kinetics of sodium chloride and the interaction of molecular beams containing NaCl monomers and Na2Cl2 dimers with tantalum and deposited sodium chloride films. Using a molecular beam apparatus with mass spectrometric detection, the authors measured Langmuir evapo…
This paper studies the non-self-adjoint differential operator \(Ly=-y''+p(x)y\) in \(L^2(-\infty,\infty)\), where \(p\) is complex-valued, with emphasis on square-integrable solutions and discreteness of the spectrum. Using an analogue of Prüfer’s substitution, the second-order equation is reduced t…
This note studies Euler normal classes for smooth immersions and embeddings, focusing on immersions homotopic to a fixed immersion and on embeddings of closed nonorientable manifolds in Euclidean space. In the metastable range it describes the realizable normal classes of immersions in terms of the …
The crystal structure of isothiocyanato-dinitro-(ethylenediamine)-amminecobalt(III) was determined to verify the ligand configuration inferred from chemical substitution reactions and the trans influence. Monoclinic crystals in space group P21/c were studied by X-ray diffraction using Patterson and …
This paper studies the dynamics of a simple nonlinear impulse control system containing an integrating element, a static nonlinearity, and a linear distributed element governed by a parabolic boundary-value problem. Using point transformations at impulse instants, it derives finite-iteration mapping…
This paper studies cardinal invariants of Hausdorff bicompact spaces, especially the Suslin number, bitightness, and the character and height of points. It introduces the notions of height, bitightness, and divergence, establishes closure and decomposition lemmas for compact spaces, and uses them to…
This paper formulates equations of nonlinear elasticity in terms of displacements for finite deformations, using Green, Almansi, and Hencky strain tensors together with true and generalized stress tensors. It derives variational relations, stress potentials, boundary conditions, and constitutive law…
Low frequency oscillations in a bounded low pressure helium plasma placed in an axial magnetic field are investigated experimentally with controlled variation of the end electrode potential. Using Langmuir probes and spectral measurements, the study shows that oscillations arise when the end potenti…
Stationary diffusion of particles near partially absorbing, or gray, bodies is formulated for linear transport equations and boundary conditions by decomposing the distribution function according to the number of nonabsorbing collisions with the body. The paper shows that the gray-body problem can b…
This paper studies vibrostability for differential equations in which a state depends on a time-varying control and, in particular, on the derivative of that control, a setting motivated by systems with hysteresis such as elastic-plastic elements. It defines vibrostability as the continuous extendab…
The paper addresses one-to-one coding of words and statements over arbitrary finite alphabets, in contrast to contraction methods that may lose uniqueness and prevent recovery of the original text. It defines alphabets, dictionaries, words, and statements formally, then constructs a coding by identi…
This study examines density variations among natural diamond varieties, including ordinary transparent crystals, coated diamonds, ballas, and carbonado, using a modified high-precision flotation method with improved temperature control. Densities were determined by comparing specimen equilibrium tem…
This paper reports measurements of the infrared absorption spectrum of liquid water at elevated temperatures, extending the accessible range to 4500 to 1500 cm−1 by using high-resistivity single-crystal silicon windows in a high-temperature cuvette. The authors describe corrections for thermal emiss…
The paper investigates whether vapors produced by intense irradiation of a solid surface can become opaque and shield the surface from further incident radiation. Using an explosive light source formed by a shock wave in argon or xenon, the authors irradiated targets of several materials and recorde…
This paper investigates short-wave radio pulses accompanying detonations of spherical solid high-explosive charges and examines whether their time characteristics can be used to infer ionization conditions behind the explosion shock wave. Radio emission was recorded at frequencies above 1 MHz for ch…
This paper develops a time-dependent theory for the generation power of organic dye lasers without assuming equality between gain and loss coefficients. Starting from rate equations for pump absorption, stimulated emission, losses, and population accumulation at a metastable level, it derives approx…
This paper analyzes the dynamics of a rigid unbalanced rotor supported by rolling bearings with preliminary axial preload, a configuration used in high-speed precision assemblies to increase stiffness and reduce clearance effects. An analytical relation is derived between axial spring stiffness and …
This paper addresses the difficulty of solving boundary value problems in shallow shell theory caused by the lack of complete systems of solutions for the governing equations. Using integral representations of the general solution, it constructs families of regular solutions expressed through comple…
This note formulates an optimal stabilization problem as a two-person differential game for controlled systems with an integral performance functional and opposing control components. For the linear time-varying case, it gives a necessary and sufficient condition for the existence of an optimal admi…
This paper reports a longitudinal pumping scheme for a tunable rhodamine 6G solution laser using a prism dispersion resonator, in which the pump and lasing beams are fully superposed in the active medium while losses at optical surfaces are minimized. Experiments with rhodamine 6G in isoamyl alcohol…
This paper studies idempotents in crossed products of groups and associative rings, focusing on the subgroup generated by the group elements occurring in the finite support of an idempotent. It proves that the support subgroup of any central idempotent in an arbitrary crossed product is a finite nor…
This paper derives a simple integral of the magnetic induction equation for an incompressible dissipative plasma by comparing it with the momentum-transfer equation including viscosity and Maxwell stresses. Under the conditions of zero total-pressure gradient and equality of kinematic viscosity and …
This paper studies linearized perturbed motion in nonstationary automatic control systems whose plant and regulator parameters vary slowly and whose regulator action is represented by convolution integrals with impulse transient functions. It develops a formal asymptotic construction for particular …
The paper studies positive weak solutions, in the Sobolev sense, of elliptic equations of arbitrary order in bounded domains with smooth boundary, including uniformly elliptic equations with bounded coefficients and equations degenerating at the boundary. It introduces weighted integrability spaces …
This paper proposes a Monte Carlo algorithm for estimating the eigenvalue of largest modulus of an integral operator by iterating the resolvent rather than the operator itself. The method represents powers of the resolvent through a binomial operator expansion and expresses the required scalar produ…
This note studies the approximate construction of fixed points of continuous mappings under hypotheses related to the Brouwer, Kakutani, and Lefschetz-Hopf theorems, using numberings induced by simplicial subdivisions. It defines representative and normal simplices through vector functions associate…
This paper studies nonlinear mixed boundary value problems for almost linear first order hyperbolic systems in a plane rectangle, focusing on the case where a classical solution loses regular continuability because the boundary relation becomes degenerate while the solution remains bounded. Under in…
This paper studies first boundary-value problems with weighted boundary conditions for higher-order degenerate elliptic equations in bounded domains whose boundary includes a flat degeneracy portion. It introduces weighted Sobolev-type spaces defined by iterated differential operators with measurabl…
This paper develops a quantum theory of transverse conductivity and the Hall angle for polarons in three-dimensional disordered systems where dc transport is governed by nonadiabatic hopping between localized centers. Using Kubo-formula expressions with approximate averaging over local energy fluctu…
A quantum theory is developed for the frequency dependent conductivity of polarons in three dimensional disordered systems with spatially and energetically inequivalent localization centers, such as impurity conducting materials at low carrier concentrations and temperatures. Using a Kubo formula an…
This paper generalizes Esseen’s inequalities for estimating the uniform distance between a nondecreasing bounded function and a function of bounded variation from the closeness of their Fourier-Stieltjes transforms on a finite interval. It proves an inequality bounding the supremum of |F(x) minus G(…
This paper studies the asymptotic distribution of eigenvalues for the Friedrichs extension of a symmetric constant coefficient differential operator on a bounded domain. Assuming the symbol tends to infinity and that the area of the level surface is negligible relative to the volume of the sublevel …
This paper investigates the spatial and energy distributions of medium-energy ions scattered by a single crystal, using a specially constructed apparatus capable of varying incidence, target rotation, and polar and azimuthal scattering angles. Experiments with 30 keV argon ions incident on the (100)…
This note studies Whitney’s problem on the possible normal Euler numbers of smooth embeddings of nonorientable closed surfaces in four-dimensional Euclidean space, focusing on the projective plane and the Klein bottle. The argument reduces embeddings to special forms and translates the question into…
The paper formulates finite plane deformation problems for an ideally elastic isotropic body in complex coordinates of the initial configuration, without imposing geometric or physical linearization. It derives geometric compatibility relations in terms of logarithmic strain invariants and rotation,…
This paper investigates the nonstationary onset of thermal convection in a horizontal layer of viscous liquid heated from below, using time-resolved temperature measurements across the layer. Experiments with oils, glycerin solutions, alcohols, and water compare observed temperature profiles with th…
The paper studies vector bundles equipped with fiberwise module structures over finite-dimensional associative algebras and applies these structures to cobordism theory. It establishes criteria for local triviality via linear homogeneity, constructs universal fibered modules for fixed typical fibers…
The paper studies scattering for a self-adjoint system of ordinary differential equations on a half-line with a compactly supported Hermitian matrix potential, comparing the perturbed wave group with the free Dirichlet wave group. Using the Lax-Phillips and Adamyan-Arov framework, it derives an expl…
The paper studies completeness of systems of functions in finite-valued logic under codings of finite sets and up to coding, with emphasis on the three-valued case. It introduces a partial order on equivalence classes of codings by majorization, analyzes special codings, and uses these notions to re…
This note extends Michael’s theorems on continuous selectors of lower semicontinuous multivalued mappings to mappings whose values lie in separated uniform spaces. It introduces uniform metrizability and uniform almost metrizability relative to a weaker countably based uniformity, and proves selecto…
This paper examines how generally covariant observable, or assigned, quantities transform between arbitrarily moving reference frames in special and general relativity. Using Zelmanov’s chronometric invariant formalism, the authors represent each reference frame by a unit timelike vector field and a…
This paper examines how phase transitions in cyclopentane are manifested in low-temperature infrared absorption spectra, focusing on the temperature dependence of the 546 cm⁻¹ band width from 300 to 80 K. Measurements show changes in slope or discontinuous jumps at crystallization and at the crystal…
