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
The paper studies bifurcations in systems of ordinary differential equations depending on a parameter, focusing on the birth of periodic motions from trajectories that leave an equilibrium and return to it in n-dimensional space. It first treats the case of a saddle-node equilibrium with one zero ch…
This paper studies the error of summation methods for Fourier integrals in spaces \(L_p(-\infty,\infty)\), comparing it with best approximation by entire functions of bounded degree. It establishes lower and upper estimates for the deviation \(R_\lambda(f;\varphi)\) in terms of the approximation qua…
This paper examines how the structure of crystals formed from supercooled aerosol flows depends on growth conditions, with particular attention to transparent and opaque ice produced during icing. Using theoretical estimates of the equilibrium thickness of a flowing water film and laboratory experim…
This paper develops an analogue of Herbrand’s theorem for a sequent formulation of the pure constructive, intuitionistic predicate calculus with multiple disjunctions. It introduces Skolem function systems, lexical examples, regular junctions of examples, and corresponding normality and regularity c…
This note extends Sobolev’s spaces of abstract additive set functions from bounded domains to spaces on all of Euclidean space and studies Fourier transforms in this setting. It defines the Banach spaces of such set functions, examines normality, translation continuity, density of finite functions, …
This paper examines whether the steep current rise observed during cathodic polarization of unbuffered lanthanum chloride solutions reflects an autocatalytic electrode process. Using direct and reverse polarography at a dropping mercury cathode, instantaneous current versus time measurements, and po…
The paper studies boundary value problems for second order systems of partial differential equations of mixed type with symmetric matrix coefficients, hyperbolic in one half-plane and elliptic in the other. It formulates a mixed-domain problem with boundary data prescribed on part of the boundary an…
This paper establishes criteria for systems of analytic functions in a disc to form quasi-power bases in spaces of analytic functions. Using the representation of these spaces as projective limits of Banach spaces and applying Fredholm theory to associated linear operators, the authors extend earlie…
This note studies method of lines approximations for one-dimensional parabolic and hyperbolic boundary value problems whose coefficients and derivatives have finite jump discontinuities along fixed spatial lines. It constructs homogeneous differential-difference schemes on meshes aligned with the di…
This study examines the mechanism of catalytic oxidation of propylene to acrolein and carbon dioxide over a cuprous copper catalyst under conditions close to those used for acrolein synthesis. Using carbon-14 labeled acrolein and propylene in a flow reactor, the authors compared product radioactivit…
This note studies the negative spectrum of the multidimensional Schrödinger operator Mh u = minus h Delta u minus P(x)u in L2(Rn), for n at least 3 and nonnegative locally bounded potential P. Using capacity estimates for condensers and closed sets, it formulates criteria for positivity inequalities…
This paper describes an optical method for detecting first-order phase transitions in transparent polycrystalline salts under static pressure and for using these transitions to calibrate high-pressure chambers for spectral studies. A chamber with rock-salt windows was constructed for pressures up to…
The paper develops a general framework for monotone two-sided approximation methods for equations in partially ordered convergence groups, extending earlier treatments in conditionally complete ordered linear structures and topological groups. It defines partially ordered and semi-ordered convergenc…
The study examines polymerization of 4-phenylbutene-1 using a Ziegler-type catalytic system of triisobutylaluminum and titanium tetrachloride in hydrocarbon solution under nitrogen. Polymerization conditions were varied by temperature and catalyst-component ratio, and the resulting solid and liquid …
The study examines transformations of di(boracycloalkyl)alkanes and 1-alkoxyboracycloalkanes with methyl borate in the presence of tetraalkyldiboranes. Di-1,4-(1-boracyclopentyl)butane reacts with equimolar methyl borate to give 1-methoxyboracyclopentane in high yield, while excess methyl borate aff…
The paper analyzes rectification in a stationary binary electrolyte cell containing an ideally polarizable electrode when a small-amplitude sinusoidal current is applied. Using a perturbative treatment of the diffuse layer and the transport equation for ionic motion, it derives the mean potential sh…
This paper describes a gas chromatographic method and apparatus for absolute determination of gas and vapor solubility in low volatility and highly volatile liquids through measurement of distribution coefficients in the Henry’s law region. The authors propose sealed, weighable columns with self sea…
The paper continues the study of systems of nonspecial subgroups of finite groups by introducing oriented subgroups, oriented Pi-systems, and indecomposable Pi-systems. It establishes existence results for oriented Pi-SC systems in nonspecial groups and examines how dispersiveness affects the possib…
This paper studies the construction of statistically similar regions and zonal statistics for one-parameter families of probability measures on Euclidean space. It identifies a broad class of distributions whose densities satisfy a linear differential equation in the parameter, with coefficients dep…
This paper analyzes the propagation of gravity and capillary surface waves on an ideal incompressible conducting liquid in a uniform external magnetic field, using linearized magnetohydrodynamic equations under the assumption of small wave amplitude and effectively infinite conductivity. For a field…
This paper studies a class of congruences of conics in three-dimensional projective space for which one focal surface degenerates to a point and two nondevelopable focal surfaces carry conjugate nets related by Laplace transformations. Using a canonical moving frame, it derives the differential form…
This paper analyzes the form of the electrophotographic isopaque, defined as the dependence of logarithmic exposure on logarithmic light intensity for a fixed crystal charge, within a single local level band model of an n-type crystal. Using kinetic equations for conduction electrons, trapping level…
The paper studies inverse semigroups with zero and a finite number of idempotents, giving a structural description through finite ideal composition series whose factors are completely simple semigroups with finite identity defining matrix. It introduces a matrix of maps into semigroup algebras that,…
This paper proposes a molecular-mechanical interpretation of how an interface and rupture surface form when rubber and similar polymers are deformed in the highly elastic state. Using the hypothesis of microneck formation, it models the neck as an elastically stretched bundle of oriented macromolecu…
This note studies boundary value problems for second order elliptic equations whose coefficients are discontinuous across an interior hypersurface. Using Sobolev spaces adapted to the interface conditions, the authors formulate generalized solutions and prove a Gårding type inequality, which yields …
This note studies Beurling-type semigroups of real numbers divided into finitely many multiplicative classes, under uniform asymptotic counting assumptions with an unbounded class parameter. It proves a general theorem giving bounds for the existence, in every class, of a basic number in short multi…
This paper studies the discrete spectrum of the radial Schrödinger equation on the half-line with a centrifugal term and a potential whose behavior at infinity begins with Coulomb-type terms. Using variational characterization of the lowest eigenvalue, asymptotic analysis, and a spectral approximati…
This study examines the surface tension of binary alkali silicate melts, including previously unmeasured rubidium and cesium silicate systems, over alkali oxide contents of about 16 to 45 mol.%. Using an improved drop-weight method, the authors compare these melts with earlier data and evaluate temp…
This paper addresses the synthesis of analog computing and solving devices for tracking roots of systems of finite equations whose parameters vary with time. It proposes replacing conventional discrepancy working-off schemes, which can have nonzero steady-state error, with a dynamical system derived…
This paper examines how intramolecular mutual influence in complex molecules can appear not only through changes in diagonal bond force constants, but also through off-diagonal force coefficients coupling different internal coordinates. Using infrared and Raman spectral data and approximate frequenc…
This study investigates the radiolysis of aqueous solutions of several rhodium salts under irradiation by 0.8 MeV electrons, with attention to the conditions under which metallic rhodium is formed. Solutions of rhodium chloride, sulfate, nitrate, perchlorate, and monochloropentaamminerhodium chlorid…
This paper examines the structure of the unstable uranyl nitrate nitrogen dioxide complex traditionally formulated as UO2(NO3)2·2NO2, for which several arrangements of nitrogen dioxide or dinitrogen tetroxide were possible. The authors use Gouy magnetic susceptibility measurements and infrared vibra…
This paper examines why molecular oxygen intensifies chemiluminescence in radical reactions, despite its known quenching role in photoluminescence. Using the thermal decomposition of azobisisobutyronitrile in hydrocarbon solutions, the authors compare chemiluminescence under oxygenated and oxygen-de…
This study investigates the direct formation of hydrogen cyanide from methane and ammonia during rapid adiabatic compression, with argon used as an inert diluent after nitrogen-containing mixtures failed to produce detectable HCN. Experiments with several methane, ammonia, and argon mixtures up to 1…
The paper introduces and studies quasi-operator groups, or Ω-groups, generalizing Kontorovich’s R-groups by allowing operators from a principal ideal ring, and develops basic notions such as Ω-admissibility, Ω-isolation, ΩR-groups, and Ω-locally cyclic subgroups. It records extensions of standard re…
This paper studies embedding problems for several classes of algebras over a fixed field, including arbitrary nonassociative, commutative, anticommutative, and Lie algebras. It defines systems of algebraic equations over free products, introduces a notion of strong algebraic closedness based on cons…
The paper examines the problem of obtaining sufficiently bright ion projector images of very small tungsten microcrystals, for which normal tip geometry causes image brightness to fall sharply with decreasing radius. The authors propose using short protuberances formed on tungsten tips during contro…
This paper studies lattice coverings of n-dimensional Euclidean space by equal balls and focuses on the lattice constructed from a regular Selling frame, whose metric form is Voronoi’s principal form of the first type. Using Dirichlet regions, Selling parameters, and a related variational problem pr…
This paper reports synthetic routes and reactivity studies for little-studied polyfluorinated aliphatic azo compounds. The authors prepare polyfluoroazoalkanes and derivatives by reduction of azoxy compounds, oxidation of hydrazo compounds, fluorination of azines or polyfluorocarboxylic acid nitrile…
This paper studies the asymptotic distribution of eigenvalues for bilinear forms associated with higher order elliptic operators whose leading coefficients are weighted by a power of the distance to the boundary, producing boundary degeneration. Working in weighted Sobolev spaces and using estimates…
This paper investigates whether cuprous oxide, whose visible exciton spectra were already known to include yellow, green, blue, and violet series, also exhibits exciton-related structure in the ultraviolet region. Using polarized reflection measurements near Brewster’s angle at liquid nitrogen tempe…
This paper examines the mechanism of nickel electrodeposition from acidic nickel sulfate solutions with particular attention to the role of electrode surface passivation. By comparing overvoltage relative to stationary and equilibrium potentials over a wide temperature range, and by analyzing polari…
This paper studies uniqueness and bending of simply connected surfaces of strictly positive Gaussian curvature with smooth boundary under various boundary constraints. Using an index associated with a continuous field of directions along the boundary, it establishes criteria for when an isometric tr…
This study examines the mechanism of chain initiation in the liquid phase oxidation of n-decane, testing whether radical formation proceeds through a bimolecular hydrocarbon oxygen reaction or a trimolecular process involving two hydrocarbon molecules and oxygen. The authors used an inhibitor method…
This study examines the structure of associated aliphatic organolithium compounds in solution, focusing on the assignment of infrared absorption bands to C-Li groups and to groups involved in aggregation. Infrared spectra of isotopically substituted compounds, including lithium-6 and deuterated ethy…
This study examines supramolecular structure formation during crystallization of purified isotactic polystyrene and its dependence on crystallization temperature and time. Samples crystallized between 110 and 215 degrees C, with systematic observations at 120, 145, and 175 degrees C, were analyzed b…
This paper investigates the neutral component of secondary emission produced when solid tantalum targets are bombarded by positive alkali ions, with emphasis on whether neutralized primary particles leave the surface with appreciable residual energy. The authors use a two-target apparatus in which c…
This study examines catalytic hydrogenation routes from 2-substituted indandiones-1,3 to the corresponding indandiols-1,3, compounds related to medicinally important indandione anticoagulants. Using skeletal nickel catalyst in alcoholic solution, the authors hydrogenated 2-benzylideneindandione-1,3 …
This study examines the addition of acid esters of phosphorus acids to unsaturated polyesters derived from maleic anhydride and various glycols, a reaction class previously little explored for such polymers. Using sodium methylate as catalyst, the authors reacted dialkyl phosphorous, thiophosphorous…
This study determines atomic scattering factors and electron density distributions in aluminum antimonide at 20°C and −100°C, completing a comparative series on group III antimonide semiconductors. Using X-ray powder diffraction with CuKα radiation, the authors calculate lattice constants, structure…
