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 note studies V. A. Steklov’s conjecture that positivity of the weight is necessary and sufficient for boundedness of an orthonormal polynomial system on an interval. Working first with polynomials orthonormal on the unit circle, the paper gives sufficient conditions, involving pointwise bounded…
This paper examines whether the brightness variations of long-period variable stars can be explained by mechanisms other than ordinary stellar pulsation. Using reported rapid optical and near-infrared brightness changes, together with estimates of photon escape time from subphotospheric layers, it a…
This paper studies expansions in eigenfunctions for a non-self-adjoint system of differential equations of arbitrary even order on the half-axis in the space of vector functions. Under exponential decay assumptions on the matrix coefficients and regularity conditions on the boundary forms, it constr…
This note revisits Regge’s theorem on the analytic continuation of functions expanded in Legendre polynomials, where the coefficients are values of an analytic interpolating function in a half-plane. It argues that the theorem follows from the classical Le Roy-Lindelöf theorem on power series togeth…
This paper examines whether contemporary pulsational vertical movements of the Earth’s crust show temporal relations with solar activity. Using long tide-gauge records from more than 40 stations on the Caspian Sea, with particular attention to Baku relative to Makhachkala and other reference gauges,…
This paper investigates adsorption of 1-methylcyclohexene-1 from n-heptane solutions on alumina at elevated temperature, with attention to conditions relevant to chromatographic separation and heterogeneous catalysis. The authors develop an ampoule method that separates the equilibrium solution from…
An iterative finite difference method is proposed for the first boundary value problem for the Poisson equation, using the standard five point approximation on rectangular grids. The method alternates one dimensional implicit steps in the coordinate directions and is analyzed through the eigenfuncti…
The paper studies the asymptotic enumeration of primitive integer matrices of order three with prescribed determinant N, restricted after scaling to a fixed bounded domain in the group of unimodular matrices. It proves that, as N tends to infinity, the count is asymptotic to the Haar measure of the …
This paper analyzes quantitative relationships between structure and reactivity for the alkaline hydrolysis of several series of aromatic sulfonic acid esters, using literature rate constants for substituted phenyl, benzenesulfonyl, diaryl, and ethyl benzenesulfonate derivatives. The authors apply m…
This paper studies nondegenerate congruences of parabolas in equiaffine geometry under assumptions on a distinguished focal surface. A canonical moving frame is constructed, yielding structure equations, invariants, the equation of the parabola, and the determination that the general congruence depe…
This study examines preferential chemical interaction between nickel and manganese in ternary copper-based solid solutions, using the Cu-Ni-Mn system where the NiMn compound has limited thermal stability. Alloys along sections intersecting the quasibinary Cu-NiMn section at 90 and 95 atomic percent …
This study examines complex formation between several chlorosilanes, including methyltrichlorosilane, trimethylchlorosilane, phenyltrichlorosilane, and silicon tetrachloride, and a range of alkali, ammonium, and tetrasubstituted ammonium halides. Interactions were assessed by chemical analysis, visu…
This paper analyzes nutational oscillations and drift in a synchronous gyroscope mounted in a gimbal suspension when the gimbal rings are not perpendicular and the stator magnetic field torque affects the motion. Using Lagrange equations, the study derives equations of motion, first integrals, stabi…
This paper proposes a mathematical model for separated flows of an incompressible ideal fluid in which the flow is potential outside a separation region and has prescribed constant vorticity inside it. The model is formulated through a stream function satisfying a nonlinear free boundary problem, eq…
The paper studies when the exact Künneth sequence for tensor products of complexes splits, especially in the case where only one factor is torsion free. It gives an explicit two term example, with one complex over the integers and one over the cyclic group of order 8, in which the degree one Künneth…
This study examines complex formation between tetravalent uranium and nitrate ions in hydrochloric, nitric, and mixed acid media, using spectrophotometry, ion exchange, and preparative isolation. It finds stepwise formation of lower cationic and neutral nitrate complexes at nitric acid concentration…
This study examines the state and bonding of water sorbed on low-temperature calcium hydrosilicate, focusing on the interpretation of a characteristic dehydration isotherm section near relative vapor pressure 0.35. Proton nuclear magnetic resonance spectra were measured at room temperature for sampl…
The paper studies linear operators on the space of continuous periodic functions that take values in trigonometric polynomials of bounded order, classifying such operators by an averaging procedure invariant under translations. It establishes a one-to-one correspondence, with natural algebraic inter…
This paper examines how the transfer coefficient alpha may be estimated from the dependence of electroreduction kinetics on electrode potential and supporting electrolyte concentration, emphasizing the role of double layer corrections. Using corrected Tafel representations based on the Frumkin, Flor…
This study examines how plasticizers affect supramolecular structure formation and mechanical properties in crystalline isotactic polystyrene. Using optical observations of crystallization at several temperatures together with mechanical measurements and comparison of X-ray diffraction patterns, the…
This study examines potentiometric measurement of powdered catalyst potentials during catalytic hydrogenation in dielectric organic media, where high resistance and static charge complicate conventional methods. The authors designed and tested two variants of a measuring electrode with a conducting …
This study examines chloromethylation as an electrophilic substitution reaction of 5,6-disubstituted 2-pyrones, extending earlier work on the reactivity of the 2-pyrone ring. Using mixtures of chloromethyl and bis-chloromethyl ethers, or formalin saturated with hydrogen chloride, the authors prepare…
A semiclassical formulation is developed for electron exchange reactions between ions in solution, treating the electron quantum mechanically while representing solvent motion classically. By reducing the solvent reorganization problem to an effective one-dimensional oscillator coordinate, the analy…
The note studies representation numbers of positive definite integral quadratic forms in an odd number of variables through generating series connected with modular forms. For a squarefree parameter l, it defines weighted sums of the representation numbers r_f(lt²) and proves that their generating f…
This paper examines the synthesis of vinyl chloride by high-temperature chlorination of ethylene in a fluidized bed, motivated by the difficulty of promoting substitution chlorination while limiting destructive chlorination and by-product formation. The authors carried out experiments at 450°C using…
This paper reports experimental observations on rearrangements of dimethylcyclosilazanes involving changes in the silicon-nitrogen ring framework. Hexamethylcyclotrisilazane was treated under several conditions, including trimethylchlorosilane with ammonia, ammonium chloride, triethylmethylammonium …
This study examines isotopic hydrogen exchange in cyclopentadienylmanganese tricarbonyl as a means of comparing its electrophilic reactivity with that of benzene and previously studied metallocene systems. Exchange experiments were carried out in acidic media containing deuterated trifluoroacetic ac…
This paper develops a method for calculating the electrical conductivity tensor using retarded and advanced two-time temperature Green functions. For electrons scattered by phonons or impurity centers, the current Green function is related to a two-particle Green function whose equation has the form…
This paper addresses the experimentally observed S-shaped dependence of combustion velocity on component particle size in condensed mixtures whose components gasify before mixing, a behavior not adequately described by one-dimensional theories. The authors propose a simplified nonuniform combustion-…
This paper develops a theoretical description of the dynamic equilibrium of a fog cloud formed by supersaturated vapor above a liquid surface in a convective airflow. The authors formulate coupled continuity and material balance equations for the droplet size distribution and vapor supersaturation, …
The study examines regularities in the infrared and Raman vibrational spectra of several organosilicon and related organoelement compounds containing vinyl or allyl C=C bonds. Spectra were measured for methylchlorovinylsilanes, methylchloroallylsilanes, trimethylsilyl alkenes with varying methylene …
This paper analyzes the motion of a liquid drop suspended in another liquid when a maintained concentration gradient of an insoluble surface-active substance produces a nonuniform surface concentration on the drop. Using a slow-motion approximation, the authors couple convective diffusion near the i…
This paper studies extremal properties of regular solutions to linear elliptic equations under general assumptions on the zeroth order coefficient and the right hand side, without requiring fixed signs for these functions. Using Chaplygin’s theorem on subcritical domains, it proves a criterion exclu…
This paper studies when topological spaces arise as images of metrizable spaces under continuous mappings with openness, closedness, compact fibers, or related conditions. It proves that a T1 space has a uniform base exactly when it is an open continuous compact image of a metrizable space, with a z…
This paper examines complex compounds formed by rhenium with thiourea in hydrochloric acid media, extending earlier work on the yellow-green analytical complex. By varying acid concentration and the molar ratio of perrhenic acid to stannous chloride, the authors identify at least four colored comple…
The paper examines the relation between operators in the Heisenberg and interaction representations, focusing on ambiguities that arise in the Dyson matrix and in products involving generalized functions. Using lowest order perturbation theory for a neutral scalar self-interacting field, it argues t…
This paper examines the magnetic susceptibility and stereochemistry of trivalent molybdenum complexes with urea, thiourea, and related derivatives. Measurements on nine compounds distinguish mononuclear complexes, which show magnetic moments close to those expected for three unpaired electrons, from…
This paper extends Sturm comparison and oscillation theory to strongly elliptic second order systems with symmetric matrix coefficients. It proves a comparison theorem showing that, under coefficient inequalities, the existence of a nontrivial solution of one system vanishing on the boundary forces …
This study examines the transformation of polyethylene from a dielectric into a material with semiconductor-like properties under combined radiation and thermal treatment. Pre-irradiated high-pressure polyethylene was pyrolyzed in vacuum at increasing temperatures, and the resulting products were ch…
Elastic scattering of 6.9 MeV protons by separated chromium and zinc isotopes was investigated to examine isotope-dependent differences in angular distributions and their implications for nuclear potential descriptions. Measurements were made for chromium-50, -52, -53, -54 and zinc-64, -68, -70 usin…
This paper addresses the design of automatic control systems for plants whose parameters vary over wide ranges, using variable-structure, piecewise-linear control laws. The authors analyze conditions under which a sliding mode arises on a switching hyperplane and show that, once the system trajector…
This note studies when the root functions of an ordinary linear differential operator on a finite interval form a Riesz basis in the space of square integrable functions. For operators of arbitrary order with sufficiently smooth summable coefficients and strongly regular boundary conditions, the pap…
The paper studies inclinations between linear subspaces of a Banach space and their relation to the existence and stability of bases. It proves auxiliary results showing that finite-dimensional subspaces of an infinite-dimensional Banach space can be separated, in the sense of inclination, from suit…
This paper examines the conditions for maintaining a stationary directed electrochemical process in irradiated sulfuric acid solutions containing water radiolysis products. The authors argue and experimentally show that a single platinum electrode, even when selective toward radiolysis products, can…
This study examines the addition of nitrosobenzene to 2-substituted conjugated dienes, specifically isoprene and 2-methoxybutadiene-1,3, in the context of diene synthesis leading to substituted 3,6-dihydro-1,2-oxazines. The structure of the isoprene adduct was established by reductive cleavage to an…
This paper proposes vacantochromatography, a variant of chromatography in which a pulse of carrier gas creates a moving vacancy in a sorbed layer rather than introducing a sorbed sample band. The authors argue from chromatographic dynamics that, in the linear sorption region, vacancy motion and spre…
This paper investigates diffusion coefficients of silicon, titanium, vanadium, and niobium in carbon-saturated liquid cast iron, addressing discrepancies and possible convection errors in earlier capillary-based measurements. The authors apply constant-current oscillography, using the time required …
The paper derives boundary growth estimates in the L2 metric for generalized solutions of elliptic-type Euler equations of arbitrary order associated with a positive definite Dirichlet integral, primarily in two dimensions with extension to higher dimensions indicated by analogy. Using normal coordi…
