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
This study examines how very high cooling rates during crystallization affect segregational microinhomogeneity and solid solution composition in aluminum magnesium alloys across a wide range of magnesium contents. Alloys were solidified using chill casting and rapid film formation on a rotating bras…
A thermodynamic analysis is presented for the MgAl2O4, Fe3O4 spinel solid solution formed during equilibrium reduction of magnesium ferroaluminate by hydrogen and coexisting with a variable composition MgO, FeO wüstite phase. Using a statistical activity model for binary spinel solutions together wi…
This study examines whether potassium, known to enrich the surface layer of liquid mercury amalgams, shows analogous surface adsorption in the solid state, and how photoelectric behavior relates to surface tension. The authors measured external photoemission currents from dilute potassium amalgams u…
The study examines the mechanism of diphenylmercury interaction with isopropyl and tert-butyl alcohols using deuterium labeling and low-voltage mass spectrometric analysis of benzene, diphenyl, and alcohol isotopic compositions. Photochemical reactions show that phenyl radicals abstract hydrogen mai…
This note studies locally flat embeddings of the sphere of codimension two in Euclidean space and defines an equivalence relation for such multidimensional knots using stable homeomorphisms. It introduces connected sum for the resulting classes and states that, for dimensions at least four, these cl…
This note studies when commutative real algebras and torsion-free rings can be endowed with a structural order making them \(f\)-algebras or \(f\)-rings, and when that order is unique. Using annihilators as components, projections, fragments, and \(p\)-closed cones generated by sums of squares, it c…
This paper reexamines the one-dimensional instability of Chapman-Jouguet detonation in the Zel’dovich-Neumann framework, focusing on how perturbations of the ignition-delay period affect flame propagation behind the leading shock. Using a linearized gas-dynamic treatment, it relates changes in flame…
This study examines the catalytic transformations of methylcyclooctane over platinum catalysts, with particular attention to whether transannular dehydrocyclization is governed by a tertiary ring hydrogen or by molecular conformation. Methylcyclooctane was passed over platinized carbon and an iron-p…
This paper examines the kinetics of C5 dehydrocyclization of o-ethyltoluene to indane on platinized carbon, with comparison to isooctane and tert-butylbenzene, in order to clarify how carbon atom hybridization affects the reaction mechanism. The authors measured product yields in a flow system over …
The paper determines the crystal structure of the hydrous borate inderborite, CaMgB6O11·11H2O, using X-ray diffraction, Patterson methods, and Fourier syntheses. The authors establish the monoclinic space group C2/c, locate Ca and Mg positions, derive coordinates for the light atoms, and describe th…
This paper studies representation of small categories as full subcategories of categories built from binary relations, directed graphs, ordered relations, and certain topological spaces. It introduces admissible and strongly admissible mappings for relations, develops several constructions that pres…
This paper examines whether free oscillations of the Earth’s rotation axis produce a measurable polar tide in the Baltic Sea, a question left unresolved by earlier studies and disputed in prior interpretations. Sea-level records from 13 Baltic ports for 1900 to 1930 were reduced to tenth-year values…
This paper addresses the preparation of 2,4-disubstituted furans, focusing on a practical route to 4-bromo-2-acetylfuran from 4,5-dibromo-2-acetylfuran. After evaluating several dehalogenation methods, the authors show that controlled reduction with zinc in aqueous acetic acid selectively removes th…
This paper studies forced discrete impulse systems with one nonlinear block, formulated as vector difference equations with a scalar feedback nonlinearity. It derives frequency-domain conditions, expressed through the amplitude-phase characteristic of the linear part, that ensure dissipativity, exis…
The paper studies an inverse problem of potential theory: whether the shape and position of a bounded connected body can be uniquely determined from equality of its external Newtonian or metaharmonic potential with that of another body. It formulates uniqueness theorems for domains in Euclidean spac…
This paper studies an iterative method for finding a point in the nonempty intersection of closed convex sets in a real Hilbert space by successive projection onto selected sets. It proves weak convergence of the generated sequence under several index selection rules, including cyclic selection for …
This review presents Yu. A. Mitropolsky’s monograph on asymptotic methods for non-stationary nonlinear oscillations governed by differential equations with slowly varying coefficients. It outlines the book’s development of Krylov-Bogolyubov type techniques for systems with one and many degrees of fr…
The paper examines how rapid rotation affects the instability and transition to turbulence of plane shear flows, using a tangential discontinuity in an incompressible rotating fluid as a model. Linearized equations in a rotating frame are used to compare two-dimensional disturbances, for which Corio…
This study examines why heterogeneous acid catalysts give different product distributions in the isomerization of alpha-pinene, a result not fully explained by carbonium-ion theory alone. Sulfuric and phosphoric acids were deposited on catalytically inactive supports including silica gel, titanium d…
The paper studies uniform approximation of solutions to polyanalytic and related elliptic equations of the form involving iterated complex derivatives, including the polyharmonic equation as a special case. Using a representation of sufficiently smooth solutions by analytic functions and a key lemma…
This study examines the catalytic behavior of X-type zeolites containing first-group metal cations in cumene cracking and n-butanol-1 dehydration. Lithium, potassium, and rubidium forms were prepared from NaX by ion exchange, characterized by X-ray analysis, and tested in a flow reactor against indu…
The paper studies a trigonometric analogue of Zolotarev’s extremal problem: among trigonometric polynomials of degree n with prescribed leading coefficients, it seeks those with minimal uniform deviation from zero on the full period. Using Chebyshev alternance and a criterion of Videnskii, it charac…
The paper studies mixed initial-boundary value problems on a semi-infinite interval in which the solution satisfies a hyperbolic equation on a finite subinterval and a parabolic equation on the remaining half-line, with possible finite jumps of the function and derivative at the interface. Using the…
This paper formulates a statistical mechanical treatment of transport processes in systems whose particles have internal degrees of freedom, such as complex molecular gases with slow exchange between translational and internal energy. It models the system by a second-quantized Hamiltonian in which m…
This study examines the reactions of hexamethyldisilazane with phenyl isocyanate and phenyl thioisocyanate, with particular attention to the effect of elevated temperature on products formed from silicon, nitrogen bond cleavage and silyl group migration. Experiments at 120 degrees showed that equimo…
This paper formulates a hydrodynamic description of stationary cloud systems in which motion inside the cloud is treated as pseudoadiabatic and motion outside as adiabatic, with the cloud boundary determined as part of the solution. Using axisymmetric steady equations, a stream function is introduce…
The paper addresses the realizability of unimodular integral quadratic forms as intersection forms of simply connected closed smooth four-dimensional manifolds. Building on the classification of homotopy types by intersection forms, it constructs explicit four-manifolds using membranes, surgeries on…
This paper studies conformal metric properties of doubly connected domains and their role in generalized Blaschke products. It establishes uniform bounds for boundary distortion under classes of univalent conformal maps of annuli into the unit disk, with constants depending only on the modulus of th…
The paper studies a stochastic linear programming problem in which the right-hand sides of linear constraints are independent random variables with known means and variances. It compares the random feasible region with regions defined by shifted lower and upper constraints, uses Chebyshev bounds to …
The article presents a method for analyzing finite automata by treating their transition matrices as multi-terminal networks over an algebra of events, with operations of union, product, and iteration. It proves that eliminating a terminal preserves the complete conductances between all remaining te…
This study examines the state and mobility of oxygen associated with silver films, a problem relevant to mechanisms of selective oxidation catalysis on silver. Using static vacuum experiments and mass spectrometric analysis, the authors measured isotopic exchange between oxygen adsorbed on evaporate…
This paper studies boundary properties and embedding type results for anisotropic Sobolev classes with weighted summability in smooth domains, where different coordinate directions may have different differentiability and integrability parameters. It identifies a class of regular domains, defined re…
This paper examines invariance in model-based non-search self-adjusting control systems whose plant parameters may vary at rates comparable to system transients and then become constant. Using a differential-equation representation of the plant, controller, adaptation laws, and reference model, the …
This paper reports an unexpected protodehalogenation reaction observed during studies of hydrogen isotope exchange in haloferrocenes in acidic media. Experiments with deuteriotrifluoroacetic acid show that iodoferrocene rapidly forms the ferricinium cation and an iodoferrocene iodine complex, and re…
This paper introduces a multidimensional analogue of the one-dimensional Green functions used in scattering and inverse scattering theory for the Schrödinger equation with a decreasing potential. It defines Green kernels associated with a non-self-adjoint Laplacian in exponentially weighted spaces a…
The paper addresses the mechanism of hydrolysis of the borohydride ion and its relation to diborane hydrolysis, arguing that the usual gross equation obscures the role of hydrogen ions and intermediate hydroxyborohydride species. On the basis of prior evidence and new kinetic measurements in borate …
This study examines the ultraviolet-induced chain photochemical hydrobromination of ethylene in frozen hydrogen bromide mixtures, using differential thermal analysis during irradiation, dark holding, and controlled heating. The experiments show that illumination at liquid nitrogen temperature create…
This communication describes a continuous solar-pumped optical quantum generator using Dy2+ ions in CaF2 operated at liquid nitrogen temperature, extending earlier solar excitation experiments performed at liquid neon temperature. The authors prepared CaF2 crystals doped with dysprosium, converted D…
This paper studies how aggregating states in a finite reversible stationary Markov chain changes the spectrum of the associated stochastic matrix and when such aggregation preserves the Markov property. Using the spectral decomposition of a symmetric correlation table, it characterizes “stationary” …
This note studies boundary elements associated with quasiconformal mappings of domains in n-dimensional Euclidean space, continuing an earlier definition in terms of equivalence classes of regular sequences of subdomains. It proves that, for domains quasiconformally equivalent to a ball, every bound…
This paper examines the ring structure of cyclic polymers formed from dimethacrylamides and compares them with polymers obtained by partial thermal deamination of corresponding polymethacrylamides. Using infrared spectroscopy, especially the positions and separations of carbonyl absorption bands, th…
The paper studies the oblique derivative boundary value problem for a second order uniformly parabolic equation in a possibly noncylindrical domain with Hölder continuous data and coefficients. Its method derives boundary Schauder estimates by first treating the heat equation in a half strip with a …
This study examines the reactions of 1-chloroboracyclopentane, 1-chloroboracycloheptane, and 1-n-butylmercaptoboracyclopentane with various amines to determine their tendency to form boronium salts or aminoboracycloalkane substitution products. The experiments show that product distribution depends …
