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 studies a one-phase generalized Stefan problem for a parabolic equation with nonlinear dependence on the unknown function, its spatial derivative, and the moving boundary and velocity. The problem is reformulated as a system of integral equations using Green’s functions for the heat equat…
The paper determines the crystal structure of beryllonite, NaBePO4, using X-ray diffraction data from Weissenberg photographs and analysis of interatomic-vector and electron-density projections. The study confirms the monoclinic space group P21/n and refines atomic positions through successive Fouri…
This note describes the general form of solutions to homogeneous linear partial differential equations with constant coefficients in broad spaces of ordinary and generalized functions, including Gevrey-type spaces. Extending earlier formulations of the Ehrenpreis fundamental principle, it represents…
This study examines organometallic chelate polymers as solid catalysts with properties potentially intermediate between inorganic catalysts and enzymes. Using hydrazine decomposition as the principal test reaction, and also considering dehydrogenation of isopropyl alcohol and formic acid, the author…
This paper examines how lattice energy and dispersion affect the reactivity of solids in decomposition and formation reactions involving complex anions, especially carbonates and sulfates. It develops thermochemical expressions linking activation energy and reaction heat to the lattice energies of i…
This paper examines how association of organolithium active centers affects the kinetics of lithium-initiated polymerization of styrene, isoprene, and butadiene in hydrocarbon media. Using optical density measurements to separate initiation from chain growth, and dilatometric rate measurements over …
The paper studies the Cauchy problem for second order parabolic equations in Euclidean space whose coefficients may grow at infinity. It develops an operator theoretic approach, using a weighted transformation of the equation, nonpositive maximal operators in Hilbert space, and an analogue of essent…
This paper proposes a mean density method for computing the motion of interacting charged particles on electronic computers, motivated by the difficulty of directly integrating very large many-body systems with limited machine memory. The method replaces individual interactions by fields evaluated f…
This paper studies the analytic reducibility of ordinary differential equations in a neighborhood of an invariant torus filled with quasi-periodic trajectories. Assuming that the linear variational system with conditionally periodic coefficients has already been reduced to constant coefficients, the…
The paper studies perturbation determinants for pairs of operators in a separable Hilbert space whose perturbations, or resolvent differences, are nuclear, and relates these determinants to trace formulas. It establishes results for self-adjoint operators with nuclear difference, including an integr…
This note studies a neutral differential equation with a constant small delay, in which the right hand side depends on the delayed derivative, and examines the behavior of its solution as the delay tends to zero. Under smoothness assumptions and a stability condition bounding the derivative of the r…
The study examines whether peroxide compounds can initiate homolytic reactions between organotin compounds and alkyl halides, which are otherwise relatively inert under comparable conditions. Benzoyl peroxide was heated under nitrogen with mixtures of tetraethyltin, dimethyldiethyltin, hexaethyldist…
The study examines the polymerization of allylcyclohexane in n-heptane at 70°C under nitrogen using the catalytic system titanium tetrachloride with triisobutylaluminum. Allylcyclohexane was synthesized and purified, then polymerized in sealed ampoules and in an open system while varying catalyst ra…
The paper studies singular Cauchy problems for the Chaplygin equation in a half-plane near the degeneracy line, focusing on the construction of singular kernels and Riemann type functions. It introduces Duhamel and Doetsch resolvents with discontinuous boundary data, reduces their computation to mix…
This study examines whether chymotrypsin forms a detectable acyl-enzyme intermediate during hydrolysis of the p-nitrophenyl ester of carbobenzoxy-D-phenylalanine, a D-amino acid ester expected to react more slowly than corresponding L-substrates. Kinetic measurements showed an initial burst of p-nit…
This paper analyzes radiation produced when the electromagnetic field of a point charge is diffracted by an ideally conducting half-plane, for a particle trajectory perpendicular to the screen edge and arbitrary particle velocity. Using Fourier components of the electromagnetic potentials and Wiener…
The paper studies weak solutions of the first boundary-value problem for uniformly strongly elliptic systems of order 2m in a bounded domain, using Sobolev space formulations and Gårding-type coercive inequalities. It reduces the weak problem to an operator equation in a Hilbert space involving a bo…
This study examines the sorption of n-octane vapor by crystalline polybutylene over 50 to 115°C in order to estimate the flexibility of its polymer chains. Sorption isotherms obtained with spring balances show increasing uptake with temperature, with anomalies in the premelting region that are inter…
This paper describes a synthetic route to B-monohalogen-substituted N-dialkylborazenes and N-trialkylborazanes, compounds that were previously difficult to obtain selectively by direct reduction of boron halides. The authors reduce B-trihalogen-N-trialkylborazanes and N-dialkyl-B-dihalogenoborazenes…
The paper develops a simplified model for spherically symmetric fracture in a solid whose tensile strength is much lower than its compressive strength, focusing on the formation of a densely cracked radial zone behind an outgoing elastic wave. It assumes that radial cracks instantaneously relieve az…
This note formulates a general best approximation problem in Banach spaces with additional linear equality constraints and cone-defined inequality constraints. Under a regularity condition, it proves an analogue of Chebyshev’s theorem, giving necessary and sufficient optimality conditions in terms o…
Primary inclusions in topaz crystals from Volhynian pegmatites were examined to infer the conditions of pegmatite mineral formation. The inclusions, identified as negative crystals containing abundant quartz and muscovite with cryolite, minor fluorides and chlorides, aqueous solution, and gas, were …
The paper examines the mechanism of homogeneous free radical stereospecific polymerization of vinyl chloride in aldehyde media, a process known to yield highly crystalline syndiotactic polyvinyl chloride. On the basis of inhibition tests, ultraviolet and gamma irradiation experiments, infrared cryst…
This paper examines oscillations of tunnel current in a magnetic field as a possible probe of the conduction electron energy spectrum in metals. The authors consider tunneling between two identically oriented single crystals separated by a thin dielectric layer, with a magnetic field perpendicular t…
This paper generalizes a previous treatment of forecasting smoothed meteorological fields to a fully three-dimensional atmospheric model in which the stream function depends on horizontal coordinates, height, and time. Starting from a quasi-solenoidal dynamical equation with boundary conditions at t…
The study examines diene syntheses of glyoxylic acid esters and their hemiacetals with 1,3-dienes as a route to 5,6-dihydro-1,2-pyran derivatives, a class of reactions previously little explored for carbonyl compounds. Butadiene, 2,3-dimethylbutadiene, and 1,3-cyclohexadiene were condensed with ethy…
This study examines whether the activity of substituted ethylenic dienophiles in diene synthesis correlates with the NMR chemical shift of the terminal hydrogen atoms at the double bond. Chemical shifts were measured or taken from literature, averaged where the two terminal hydrogens were nonequival…
The paper generalizes spectral representations of mass and polarization operators from zero temperature to arbitrary temperature using retarded and advanced Green functions rather than causal functions. For a homogeneous fermion system, it derives analytic properties of the mass operator, locates po…
This paper studies conjugate nets in three-dimensional projective space whose successive Laplace transforms have fibering congruences of first and second axes. Using a moving projective frame and Cartan’s exterior differential forms, the author derives the differential systems expressing the require…
The study examines the oxidation of lead selenide by oxygen between 122 and 496°C, focusing on kinetics, oxidation products, surface area, and electrical resistivity. Powdered PbSe samples were oxidized at controlled oxygen pressure, analyzed gravimetrically with torsion microbalances, characterized…
The paper studies elliptic and parabolic second order differential equations with a small parameter multiplying the highest derivatives, motivated by oscillatory systems subject to small random perturbations and fast motion along closed trajectories. It proves averaging results for solutions in an a…
The paper studies the planar set swept out by segments joining the line y = 0 to the line y = 1 when the segment through each base point has a prescribed inclination, asking what can occur when the inclination function is discontinuous. It develops a construction using finite systems of parallelogra…
This paper gives a constructive characterization of continuous periodic functions whose trigonometric conjugates, together with the original functions, satisfy the Lipschitz condition of order one. The criterion is formulated in terms of approximation by Jackson interpolation polynomials at equally …
This note studies when a complete Boolean algebra is normable, meaning that it admits a strictly positive countably additive probability measure, by examining groups of automorphisms of the algebra. It introduces complete homogeneity, defined by a transitivity condition and a uniform continuity cond…
This note studies whether spaces of analytic functions associated with two nested nonseparating continua in the extended plane can possess a common basis when the inclusion is not strict in the sense used in earlier positive results. It introduces the notion of a continuum being a metrically separab…
This paper examines the stability of finite-amplitude Alfvén waves in magnetohydrodynamics, despite their status as exact nonlinear solutions. Using perturbation theory in a frame moving with the wave, the authors derive resonance conditions coupling perturbations whose wave vectors and frequencies …
This study examines diene synthesis reactions of oxazole derivatives bearing electron-acceptor, methyl, and phenyl substituents with maleimide and, in selected cases, maleic anhydride. By comparing yields of substituted pyridinedicarboximides and partially hydrolyzed semiamides, the authors show tha…
This note proves sufficient conditions for essential self-adjointness of the minimal operator in L2 on the real line generated by the even-order differential expression ly = (-1)n y(2n) + q(x)y, where q is real and continuous. The argument uses interval conditions controlling the negative part of q …
The paper extends the Goluzin-Schiffer variational method to a class of normalized univalent, nonvanishing functions in finitely connected circular domains. Using a decomposition of a conformal map into successive one-to-one conformal components associated with boundary continua, it derives variatio…
This note studies whether Riemann’s localization principle extends from trigonometric Fourier series to systems of the form \(\{\varphi(nx)\}\) whose generating function satisfies specified absolute convergence and Dirichlet series nonvanishing conditions. Although such \(T\)-systems share several g…
This note studies continuation of solutions of partial differential equations across a boundary segment under boundary conditions, using transformation operators. After recalling one-dimensional transformation operators and their kernels, it constructs reflection-type continuations for elliptic equa…
The paper formulates an approximate elastic stability problem for a vertical cylindrical mine working of circular cross section in a homogeneous isotropic rock mass. Starting from a known elastic stress and displacement field, it treats buckling as a perturbed equilibrium problem for an annular laye…
This study investigates the light-induced sorption of hydrogen on powdered titanium dioxide using pressure measurements under controlled vacuum, illumination, and sample pretreatment conditions. Hydrogen photosorption was observed only after calcination of titanium dioxide in oxygen, proceeded irrev…
This study examines the radiation chemical stability of aqueous ammine complexes of cobalt(III) and nickel(II), a topic for which little prior data were available. Solutions of hexammine nickel chloride in 5 percent ammonia and hexammine cobalt chloride in neutral water were irradiated with cesium-1…
This paper develops a theoretical treatment of electron paramagnetic resonance line narrowing and relaxation in paramagnetic solutions, where thermal motion and exchange interactions act simultaneously. Using the Kubo and Tomita formalism, it derives approximate correlation functions for fast and sl…
The paper examines the ultraviolet spectra of 2,4-dinitroaniline, 2,4-dinitrodiphenylamine, and related derivatives in order to clarify how multiple nitro, amino, and aryl substituent systems contribute to observed absorption bands. Using decomposition of molecular structures into polar chromophoric…
This paper addresses the statistical distribution of elastic constants in quasi-isotropic, single-phase polycrystals, where crystallographic orientations are random at the microscopic scale. The authors formulate the elastic-constant transformation in terms of Euler angles and derive the joint densi…
This note extends an earlier asymptotic averaging method for singularly perturbed systems of differential equations to intervals that may be unbounded in time. It formulates additional hypotheses involving Lyapunov stability of a solution of the degenerate fast system, uniform existence of time aver…
Dipole moments were measured in benzene at 25 degrees Celsius for eight imidazolidinedione, thiohydantoin, and merocyanine derivatives containing oxygen and sulfur substitutions, and the visible absorption maxima of the dyes were also determined. The data are interpreted in terms of conjugation, cha…
This paper studies the asymptotic distribution of eigenvalues for linear Fredholm integral equations with bounded kernels having a finite jump discontinuity on the diagonal. Under smoothness, nondegeneracy, and boundary-type conditions expressed through auxiliary resolvent kernels, the equation is r…
