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 examines the phase composition and behavior of copper catalysts in the oxidation of propylene to acrolein, addressing uncertainty over whether cupric oxide, cuprous oxide, or metallic copper is the active form. Copper oxide, cuprous oxide, and reduced copper on pumice were tested in propy…
The paper examines the stereochemical complexity of curare alkaloids, especially chondropholine, chondodendrine, and tubocurarine derivatives, in light of asymmetric centers, nitrogen substituent geometry, tetrahydroisoquinoline conformations, and macrocyclic diether arrangements. The authors descri…
This paper studies extremal functions for linear methods of approximation of periodic functions whose r-th derivative satisfies a Lipschitz condition of order alpha. Building on Timan’s asymptotic estimate for deviations of Fourier multiplier polynomials, it asks whether an extremal function can be …
This study examines the physicochemical nature of water in phosphotungstic and silicotungstic heteropoly acids, with attention to competing structural formulas and acid basicity. Using differential thermography, thermogravimetric dehydration polytherms, equilibrium composition temperature diagrams, …
The paper establishes topological criteria for the existence of bounded, periodic, and almost-periodic solutions of systems of ordinary differential equations with continuous right-hand sides, without assuming uniqueness or global continuability of all solutions. The authors introduce a condition in…
This paper studies interpolation by entire functions at prescribed complex nodes, focusing on growth restrictions expressed through refined order and indicators. It introduces associated functions for node sequences of refined order growth and gives necessary and sufficient conditions, involving the…
This study examines how molecular structure, especially conjugation energy and substituent effects, influences the kinetics of catalytic hydrogenation. Using rhodium on alumina under mild conditions, the authors measured hydrogen uptake rates for aromatic, heteroaromatic, conjugated, and related non…
The paper studies the free motion of a balanced gyroscope in a gimbal suspension on a fixed base when dry friction acts in the suspension axes and is proportional to the dynamic reactions. Equations of motion are formulated for the outer ring, inner ring, and rotor, then simplified for small angles …
This paper analyzes the decay of transverse circulation generated by channel curvature after the flow enters a straight reach, assuming the initial circulation distribution is prescribed. Starting from the viscous incompressible flow equations with constant turbulent mixing, hydrostatic pressure, an…
This note announces new estimates for finite trigonometric sums with polynomial phase of degree n plus 1, under a condition relating the summation length to the leading coefficient. The main theorem improves the dependence on n in the exponent compared with earlier bounds, replacing a growth conditi…
The paper studies the unsteady motion of a gas driven by an expanding piston as a model for the displacement of air by explosion products, allowing for a nonzero initial pressure. It formulates the resulting non-self-similar problem in dimensionless variables and develops a linearized expansion abou…
This study examines the origin of green and orange-red manganese luminescence in cadmium-lithium orthosilicate phosphors, addressing whether the two emissions arise from separate crystalline phases or from different centers within one phase. A series of manganese-activated compositions with varying …
The paper studies a self-adjoint fourth-order boundary-value problem on an interval in which a small parameter multiplies the highest derivative, with the highest-derivative signs matching those of the limiting second-order operator. It identifies exceptional parameter values for which zero becomes …
This note relates the representation of large integers by primitive positive ternary quadratic forms to zero-free regions for Dirichlet L-series. Assuming a hypothesis excluding zeros near s = 1 for a family of characters depending on the represented integer, the paper removes an auxiliary prime-res…
This communication reports the synthesis of new unsaturated organosilicon compounds containing methacrylic groups attached through a methylene ester substituent at silicon. Methacrylatemethylalkoxysilanes were prepared from chloromethylalkoxysilanes and potassium methacrylate, and their boiling poin…
The study examines the dehydrocyclization of n-heptane over potassium-promoted alumina-chromia catalysts, focusing on catalyst lifetime, regeneration, and the factors limiting aromatics formation. Long-duration tests at about 510 to 515°C showed that selected catalysts could operate without regenera…
The paper develops a theoretical treatment of the light regime deep within a homogeneous isotropic scattering medium, motivated by empirical regularities relevant to absorption spectroscopy of dispersed substances. Using the transport equation for the Stokes vector, it argues that in a weakly absorb…
The paper develops a hydrodynamic formulation for short-range forecasting of atmospheric pressure and motion fields from the equations of ideal adiabatic fluid motion with Coriolis effects. Using Laplace-Carson and Fourier transform methods, it derives integral representations for the homogeneous an…
This note studies bicompact extensions of completely regular topological spaces through an axiomatic theory of subordination between closed and open sets. It formulates axioms for such subordinations and shows, in a form equivalent to Smirnov’s theorem, that every subordination yields a bicompact ex…
The paper studies the approximate construction of quasiconformal mappings from the unit disk onto a prescribed domain whose boundary is given implicitly, for mappings satisfying a linear elliptic first order system with normalization conditions. The boundary correspondence is reduced to a nonlinear …
This paper examines the phase density of finite stationary self-gravitating stellar systems with an axisymmetric potential, using Jeans’ theorem and the integrals of motion for individual stars. It argues that the general phase density should depend on three independent single-valued axisymmetric in…
The paper studies the enumeration and structural recognition of indecomposable two-terminal networks, which form a topological basis for constructing arbitrary networks by superposition. It proves criteria for decomposability of simple networks in terms of an internal vertex controlling another vert…
This paper examines the local structure of liquid water using radial distribution functions derived from X-ray scattering data. Applying previously developed relations, the authors estimate fluctuations in the first two oxygen coordination numbers at several temperatures, as well as the correlation …
This paper formulates a variational approximation for a many-fermion system with two-body interactions by applying a canonical linear transformation of Fermi amplitudes and minimizing the vacuum expectation value of the Hamiltonian subject to orthonormality constraints. The resulting stationarity eq…
This study examines whether the probability of transition to a metastable state in phthalimide derivatives is related to the position of the fluorescence spectrum. Because direct phosphorescence yield measurements at low temperature are often prevented by crystallization or opacity of frozen solutio…
This paper reports two preparative routes to methylferrocene and compares the products obtained. Methylferrocene was synthesized by reduction of methyl ferrocenecarboxylate with lithium aluminum hydride in 83% yield and by reduction of N,N-dimethylaminomethylferrocene iodide with sodium amalgam in u…
The paper studies boundary value problems for linear differential equations in which small parameters multiply the highest derivatives, with emphasis on convergence as the parameters tend to zero. Using integral a priori estimates and generalized solution spaces, it proves that subsequences of solut…
This paper describes the use of transparent nomograms for approximate representation of functions of one variable by families containing three or four adjustable parameters. It formulates general relations representable by a movable transparent overlay and shows how such nomograms can be applied to …
This paper studies entire functions of finite exponential degree in several complex variables and the behavior of their growth indicators when some variables are fixed. It proves measure and exceptional set results showing that points where the degree or directional indicator falls below its maximal…
This note studies a nonlinear operator arising from the minimization of integral functionals of higher derivatives in Orlicz spaces, with homogeneous boundary conditions and a linear term determined by a right-hand side in the complementary Orlicz space. Under growth, convexity, and semicontinuity a…
This note addresses the local nilpotence of Lie rings satisfying the nth Engel condition, a problem previously settled only for small values of n. Kostrikin proves that such a Lie ring is locally nilpotent when it has characteristic zero or finite characteristic p greater than n plus the integer par…
This paper develops a thermodynamic treatment of superconductivity starting directly from the Fröhlich electron phonon Hamiltonian. Using Feynman’s operator calculus to eliminate phonon variables and applying a variational principle for the grand statistical sum, the author introduces Bogolyubov qua…
This paper studies three-dimensional Finsler spaces whose metric is defined by a cubic differential form with nonzero discriminant, using algebraic concomitants of the fundamental tensor to construct affine connections. It derives the transformation law of Tonooka’s connection under conformal change…
The paper studies the approximate construction of conformal mappings from the unit disk onto domains bounded by sufficiently smooth closed contours that need not be star-shaped. It reduces the mapping problem to a nonlinear singular integral equation and argues that Theodorsen’s iteration is inadequ…
This paper reports the first stage of systematic marine seismic investigations of the Black Sea bottom structure near Anapa, undertaken to clarify the relation of submerged Caucasus structures to the broader Black Sea depression. Using refracted-wave profiling from an expedition vessel, with explosi…
This paper examines color polymorphism in diacyl derivatives of p-aminophenol containing nitrobenzoyl or dinitrobenzoyl electrophilic systems and, in some cases, a trimethoxybenzoyl electron-donor system. A series of compounds was synthesized and recrystallized from different solvents to compare cry…
This note proposes a mechanism by which relativistic electrons can be generated when a spatially bounded quasineutral plasma clump moves through an inhomogeneous magnetic field. Using a simplified axially symmetric model and energy conservation, it argues that Lorentz forces and polarization fields …
This paper studies the uniqueness of net nomographic representations, or anamorphoses, for analytic equations in three pairs of variables under a prescribed partition of variables. Using conditions on multipliers, rationality results for algebraic anamorphoses, and a lemma identifying when two nomog…
This paper investigates ignition in homogeneous hydrogen and oxygen gas mixtures subjected to rapid adiabatic heating in a shock tube at 600 to 1400 degrees and pressures of 1 to 3 atm. Using schlieren photography, sweep recording, and piezoelectric pressure measurements, the study follows the forma…
This note studies inductive and projective limits of normed spaces, with particular attention to limits formed from reflexive normed spaces. It formulates conditions under which bounded sets in an inductive limit are already contained, and in the normed case bounded, in one of the constituent spaces…
This communication describes an apparatus and procedure for polarographic measurements with a dropping mercury electrode at pressures up to 3000 kg/cm², and reports initial tests on Tl⁺, Cd²⁺, Zn²⁺, and H⁺ in potassium chloride supporting electrolyte. The authors find that the half-wave potential an…
The paper investigates the kinetics of oxide film formation on tungsten and molybdenum over a range of oxygen pressures and temperatures using high-sensitivity vacuum quartz microbalance measurements with continuous weight recording. Experiments on specimens with different surface preparations showe…
This note gives an internal characterization of cubic complexes that arise as limiting complexes of cubic resolvents, proving that this occurs exactly for complexes satisfying the stated EN conditions. The proof constructs the associated resolvent inductively from the groups of cubes belonging to a …
This paper examines the origin of high-energy particles and hard radiation in solar flares, drawing on cinematographic, spectroscopic, radio, magnetic-field, ionospheric, and rocket observations. It argues that flare behavior is better explained by plasma compression near magnetic neutral regions, t…
The paper analyzes a quasi-stationary thermal regime in explosive reactions, in which heat accumulation is small compared with heat release and removal, so that the process may be treated as a sequence of near-stationary states. Starting from dimensionless nonstationary equations for thermal explosi…
The paper examines whether, for a continuous function on the two-dimensional torus, continuity of the pure second derivatives in a Banach function space implies continuity or membership of the mixed second derivative. It shows that although Bernstein had obtained affirmative results for certain spac…
