SovietRxiv · Open Access in English
Rediscovering the Soviet scientific archive, in English
25456 full-text translations 14926 English PDFs 22540 abstracts
Showing 50 of 25456 papers
This paper addresses the calculation of axisymmetric potential motions of a fluid in a circular pipeline containing bodies symmetric about the pipe axis, a problem for which general exact analytic solutions were not available. Two approximate approaches are proposed: an expansion of the velocity pot…
This note studies the spectrum of a self-adjoint Schrödinger operator for atoms and ions with Coulomb interactions, including the effect of nuclear motion through mixed second-derivative terms. Using variational quadratic forms, auxiliary reduced operators, and criteria for the limiting spectrum, it…
The study examines whether catalytic demethylation by water vapor, previously observed for other compound classes, also occurs in thiophene derivatives. Vapors of 2-methylthiophene and water were passed over Ni/Al2O3 and Co/Al2O3 catalysts at 200 to 425°C with varied water to substrate ratios, and l…
This study examines how alumina content affects the hydration and adsorption properties of synthetic aluminosilicate catalysts in comparison with silica gel. Samples containing 15, 30, and 50 percent alumina were thermally treated, characterized by BET nitrogen adsorption, and tested for water and m…
This paper develops a spectral representation for Chandrasekhar’s axially symmetric turbulence in an incompressible viscous fluid subject to a constant vertical temperature gradient. Neglecting third-order correlation moments, it formulates the correlation equations for velocity, temperature, and pr…
This paper examines the absorption and luminescence of light by a quantum linear harmonic oscillator in order to compare its predictions with those of classical electrodynamics. Using Einstein transition probabilities for neighboring oscillator levels, including induced emission as negative absorpti…
This note studies a generalized Riemann-Hilbert boundary value problem in the unit disk for a first order elliptic equation with negative index. By transforming the unknown, the problem is reduced to an index zero problem and then to an equivalent nonlinear integral equation, avoiding use of the gen…
This paper studies conditions under which inhomogeneous Markov chains satisfy a uniform ergodic principle, with attention to weakening commonly imposed restrictions on transition probability functions. It compares Dobrushin-type contraction conditions with a broader alternative condition, introduces…
This paper studies finite nonspecial groups through systems of nonspecial subgroups intended to parallel Sylow systems of special subgroups. It introduces and uses subgroup complexes based on groups of type S and the broader type S_p, proving existence results for such complexes under conditions inv…
This paper examines the polarization of hydrogen emission lines in nonstationary stars when the excitation or scattering radiation is linearly polarized synchrotron radiation from relativistic electrons. Using quantum mechanical scattering probabilities for excited hydrogen atoms and spatial averagi…
This paper describes a catalytic method for preparing radiocarbon-labeled unsaturated C4 hydrocarbons from C14-labeled ethyl alcohol, motivated by the difficulty and isotope losses associated with conventional multistep syntheses of labeled compounds. Using Lebedev divinyl synthesis over standard an…
This paper proposes a generalized differential-integral calculus in which differentiation or integration of arbitrary real or complex order is defined by a convergent series involving ordinary derivatives and gamma functions. It introduces an associated additional function, characterized as the gene…
This note develops a probabilistic treatment of radiation diffusion in a plane layer of finite optical thickness with isotropic scattering and photon survival probability. Using Ambartsumian’s method of adding layers, it derives equations for the resolvent of the transfer integral equation and shows…
This paper describes a method for preparing oxyalkylphosphinic acids by applying oxidative phosphorylation with phosphorus trichloride and oxygen to boric acid esters derived from several alcohols. The authors show that the reaction requires strong cooling to suppress oxidation of phosphorus trichlo…
This study examines how cetylpyridinium bromide affects the redox initiation of styrene emulsion polymerization with isopropylbenzene hydroperoxide. Using dilatometric kinetic measurements over a range of temperatures and with or without sodium carbonate, the authors compare polymerization rates and…
This study investigates layer-spiral evaporation of crystal surfaces, focusing on how growth spirals associated with screw dislocations transform when a crystal passes from growth to weak evaporation. Using direct observation and time-lapse microcinematography at high magnification, the author follo…
This paper examines M. A. Lavrentiev’s approximate formulas for conformal mappings of narrow strips arising in wave and jet problems, and interprets them as initial terms of asymptotic expansions. The authors construct formal series solutions for harmonic boundary value problems in variable strips, …
This paper derives variational expressions for the energy and effective mass of an exciton in an ionic crystal while accounting for inertial polarization of the lattice. Starting from an exciton phonon Hamiltonian, the author uses Feynman path integrals to eliminate the phonon variables and applies …
This paper proposes a practical modification of a molecular orbital method for estimating nuclear magnetic shielding constants in molecules, with particular attention to the paramagnetic term in Ramsey’s formulation. The approach assumes local Larmor precession of electrons in atomic orbitals under …
The paper studies the method of lines for mixed initial boundary value problems for systems of one dimensional parabolic equations with homogeneous initial data and general nonhomogeneous linear boundary conditions. It reformulates the continuous problem through Green’s formula as a system of Volter…
This study examines how adsorbed vapor layers affect the surface electrical conductivity of optical quartz, with relevance to surface charge formation and adhesion phenomena. Using a quartz vacuum apparatus and electrometer measurements, the authors measured conductivity during adsorption of water, …
The paper refines Perron-type asymptotic results for linear difference equations whose coefficients approach limiting values with additional regularity. It establishes representations of all solutions in terms of fundamental components with explicit product asymptotics determined by the varying root…
The study examines the kinetics of ion exchange at interfaces between liquid metals and molten slags, focusing on iron alloys and silver in oxide melts. Using measured diffusion and reaction resistances, the authors estimate diffusion coefficients, exchange currents, double-layer capacitances, and a…
This study examines the addition of mono- and polynitroalkanes to benzalacetone, with attention to how the number and position of nitro groups affect reactivity. Using ethoxytrimethylphenylammonium as a basic catalyst where needed, the authors prepared and characterized addition products from nitroe…
This paper proposes a molecular orbital method for calculating nuclear magnetic shielding constants relevant to nuclear magnetic resonance chemical shifts. Unlike perturbative approaches requiring excited-state wave functions, or variational approaches requiring highly accurate ground-state derivati…
This study examines the alkylation of diphenyl with pseudobutylene in the presence of a boron fluoride, phosphoric acid catalyst over 50 to 100 degrees, with and without carbon tetrachloride solvent. By varying reagent ratios, catalyst loading, temperature, and olefin feed rate, the authors determin…
This paper reports a method for synthesizing cyclobutane hydrocarbons by decomposing tetrahydropyridazines, extending the Kishner-type transformation beyond its established use in cyclopropane formation. Tetrahydropyridazines prepared from diene and diethyl azodicarboxylate adducts were heated with …
This paper examines the form in which silicon exists in liquid iron, a question important for understanding metallic melts and metallurgical processes. The authors measure the magnetic susceptibility of liquid iron-silicon alloys containing 0 to 60 wt.% silicon at 1600°C using the Faraday method, an…
This paper examines how rotation of methoxyl, hydroxyl, amino, and dimethylamino groups relative to the benzene ring affects conjugation in para-nitro aromatic compounds, especially under steric hindrance from ortho chlorine substituents. The authors compare Raman nitro-group frequencies and intensi…
This study examines the polymorphism of pure N-ethyl-3,4-dinitropyrrole over the temperature range from minus 100 degrees Celsius to its melting point using differential thermal analysis and dilatometric measurements. The authors identify three reversibly interconverting modifications, with transiti…
This paper presents a microanalytical method for simultaneous determination of fluorine and nitrogen in organic fluorine compounds from a single 3 to 8 mg sample. The procedure adapts the Dumas nitrogen determination by carrying out pyrolytic combustion at 900 to 950°C in carbon dioxide with nickel …
This paper develops a theoretical expression for the diffusion coefficient in liquids based on a molecular picture in which only molecules with sufficient kinetic energy and an available neighboring free space can participate in diffusion. Starting from a prior theory of liquid viscosity, the author…
This paper reports the preparation and characterization of new carbon-substituted glucose derivatives bearing anisyl substituents. Using organomagnesium synthesis, the authors obtained o-anisyltetraacetylglucose and converted it into nitro and bromo derivatives, with structural assignments supported…
This note constructs homological invariants for equimorphic transformations, defined as bijections between metric spaces that are uniformly continuous in both directions, within the class of geodesic spaces. Using domains determined by cycles whose fillings must have large relative diameter, it defi…
The paper extends a previously proposed nine-point finite difference construction for axially symmetric Dirichlet problems from the Laplace equation to the Poisson equation in cylindrical coordinates. Using Taylor expansions, it derives grid equations for interior nodes and special formulas for node…
The paper proves global unique solvability for the two-dimensional boundary-value problem for the Navier-Stokes equations with homogeneous boundary data, arbitrary initial Reynolds number, and arbitrary external force, under stated finiteness assumptions on the initial data and force derivatives. Th…
This paper investigates the formation of double chlorides of cerium-group rare-earth elements with trimethylamine chloride, extending earlier studies of rare-earth double salts with organic base salts. Lanthanum, cerium, praseodymium, and neodymium chlorides were reacted with trimethylamine chloride…
This paper investigates proton affinities of hydrogen and saturated hydrocarbons using an ion-impact mass-spectrometric method based on the detection or absence of secondary ion, molecule reactions. Experiments on formation of hydrogen and onium ions, combined with thermochemical data for dissociati…
This paper examines regularities in the relationship between polymer chain structure and melting temperature across homologous series of heterochain polymers, including polyamides, polyureas, polyurethanes, polyesters, and polyanhydrides. Using the heterochain characteristic, defined as the ratio of…
This paper examines the introduction of oxygenated side chains into ortho-methylcyclohexanone derivatives, a transformation relevant to approaches toward corticosteroid synthesis. The authors prepare cis and trans 2-methyl-1-ethynylcyclohexanols and their acetates, convert them through bromination, …
This paper studies the first boundary value problem for one-dimensional parabolic equations with coefficients and data that are piecewise continuous across a finite set of moving curves. It formulates continuity and flux-type conjugation conditions, motivated in particular by heat conduction with di…
This paper reports an x-ray spectroscopic study of the fine structure of titanium K-absorption spectra in Ti-C alloys containing 12 to 24 wt. percent carbon. Using a focusing x-ray tube spectrograph and photographic registration, the authors compare absorption edges and long-wavelength absorption ba…
This study examines whether hydrogen from the gas phase can be incorporated into solid polymer molecules during irradiation, using deuterium as a tracer. Samples of polyethylene, polypropylene, polystyrene, divinyl rubber, and polymethyl methacrylate were sealed with gaseous deuterium and irradiated…
This paper examines whether a nomogram for a three-variable equation can be improved by applying a small projective transformation that compresses one of two boundary scales while preserving the rectangular drawing frame. The author derives the first-order effect of such a transformation on line ele…
This study examines whether selective catalytic dehydrogenation can be used to characterize saturated high-molecular-weight petroleum hydrocarbons containing cycloparaffin structures. Synthetic C20 to C32 hydrocarbons with cyclohexane, decalin, cyclopentane, and normal paraffinic structures were deh…
This paper examines whether the particle size distribution of a heterogeneous urban aerosol, containing dust, smoke, and condensation nuclei, follows the logarithmic normal law previously found for more homogeneous aerosols. Measurements were made in 1951 to 1952 in the lower air layer of industrial…
This paper examines the nature of anion hydration in aqueous electrolyte solutions, arguing that the interaction between anions and nearby water molecules is closely related to hydrogen bonding in pure water rather than to the distinct cation hydration mechanism. To test this view, infrared absorpti…
This paper studies infinitesimal bendings and rigidity of surfaces, mainly surfaces of positive curvature with boundary collar constraints, including homogeneous and nonhomogeneous cases. Using the complex form of the infinitesimal bending equation in conjugate isometric coordinates and an index rel…
This paper analyzes how chain branching and chain termination affect stationary one-dimensional chain-thermal flame propagation in a decomposition reaction with active centers. A simplified kinetic scheme is combined with heat and diffusion equations to derive algebraic relations for the maximum tem…
