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
A potentiometric method is described for the quantitative acid base analysis of salts and multicomponent mixtures of salts with acids or bases in methyl ethyl ketone, addressing limitations of aqueous titration caused by non-titratable salts and leveling effects. The procedure treats the sample with…
This paper justifies a fictitious-domain method for the numerical solution of a Dirichlet problem for the Poisson equation in a plane domain bounded by coordinate-parallel line segments. The method embeds the domain in a rectangle, solves an auxiliary transmission problem with a large parameter on t…
This paper proposes a generalized framework for spectral theory of non-self-adjoint operators when invariant subspaces are complete but need not yield unconditionally convergent eigenvector expansions. It introduces generalized resolutions of the identity on rings of Borel sets, constructs associate…
This paper addresses finite two-person zero-sum positional games with perfect recall and develops a reduction of the search for optimal behavior strategies to a constrained matrix game. The method constructs an information tree for each player, preserving the partial ordering of that player’s inform…
This paper develops a theoretical description of terrestrial atmospherics produced by the return stroke of lightning and propagated in the spherical Earth, ionosphere waveguide. Representing the discharge as a vertical Hertz dipole with a prescribed current moment, the author expresses the received …
This study examines whether the single histidine residue in lysozyme is essential to its catalytic activity. Lysozyme from hen egg white was selectively modified with iodoacetic acid at pH 5.5, the reaction products were separated chromatographically, and the modified protein was compared with nativ…
This study addresses the limited knowledge of aminohalide complexes of tetravalent rhenium, especially bromide analogues, by synthesizing pyridinium hexabromorhenate and using it as a precursor to rhenium dipyridinetetrabromide. Thermal analysis, decomposition experiments, elemental analysis, conduc…
This paper examines an exactly solvable model of quantum field theory with interacting particles of three types, designed to clarify the appearance of ghost states under violations of crossing symmetry. Using Green’s functions in sectors with fixed conserved quantum numbers, the authors derive the o…
This paper studies optimal control problems for processes governed by the one-dimensional heat equation with boundary or initial controls bounded in magnitude. It proves existence of controls minimizing terminal deviation functionals, analyzes conditions under which such controls are nonunique, and …
This note characterizes paracompact spaces through projection spectra and perfect irreducible mappings. It defines regular and uniform spectra of simplicial complexes, proves that the spaces of regular uniform spectra are paracompact, and conversely constructs a complete regular uniform spectrum for…
This note formulates the problem of liquid motion of infinite depth produced by a strong explosion at a free surface, treating the liquid as incompressible after the shock wave has departed. It compares two possible self-similar descriptions, one using explosion energy as the determining parameter a…
The paper develops a general factorization theory for invertible matrix functions with entries in normed rings of continuous functions on a closed subset of the complex plane, under a rational approximation condition. It characterizes integer-valued multiplicative functionals on such matrix function…
This paper studies a general approximate method for linear problems in normed spaces, seeking finite linear combinations from an operator complete system that minimize the residual norm and converge to the best attainable approximation. The proposed method reduces the finite dimensional convex minim…
This paper analyzes the probability of phononless optical transitions in impurity centers of crystals, motivated by the analogy with recoil-free gamma transitions in the Mössbauer effect but emphasizing the different origin of lattice coupling in optical processes. Using the Condon approximation and…
This paper investigates how spherical curvature affects the normal propagation velocity of laminar flames in lean propane air mixtures, a question relevant to flame stability, combustion near ignition limits, and flame propagation in confined or low pressure conditions. Detached nearly spherical bur…
This note studies topological spaces with point-countable bases, especially the extent to which such bases imply metrizability or compactness properties. It proves that any bicompact T1 space whose base has bounded point multiplicity has base cardinality bounded by the same cardinal, yielding in par…
This paper studies embeddings of zero-dimensional compacta in Euclidean space, with emphasis on distinguishing tame embeddings from wild ones in dimensions at least three. It introduces the notion of a cellularly separated compactum and proves that any cellularly separated zero-dimensional compactum…
The paper develops an approach to uniqueness in inverse spectral problems for ordinary differential operators by relating unique determination to completeness of certain products of eigenfunctions, following and generalizing an observation of Borg. For first-order systems of vector functions with a …
The paper studies uniqueness and existence for constant coefficient partial differential equations in the whole space when the characteristic polynomial may have real zeros. It introduces thin sets relative to function spaces and uses Fourier transform support arguments to prove a uniqueness theorem…
The paper improves classical interpolation estimates for an n times differentiable function with n zeros by restricting attention to the interval between the first and last zero. It gives sharp constants for bounds on the function and its derivatives in terms of the maximum of the nth derivative, an…
This paper examines the thermodynamics of nonstoichiometric tungsten oxides in the composition range WO2.702 to WO2.976, where available data for variable-composition oxides were limited. The authors used an electromotive-force method with a calcia-stabilized zirconia solid electrolyte and an iron, …
This paper studies oscillation properties of eigenfunctions for third order boundary value problems with positive coefficient functions and a discrete spectrum. The problem is reduced to an integral equation with the Green’s function as kernel, and criteria are formulated for when this kernel is ord…
This paper investigates the radial plasma density distribution in the positive column of a helium gas discharge subjected to a longitudinal magnetic field above the instability threshold. Using movable spherical probe measurements in a long glass discharge tube, together with measurements of the lon…
The paper studies a singularly perturbed system of differential equations near a family of closed orbits of the corresponding degenerate system. Using a transformation to separate slow variables, transverse deviations, and fast variables, and applying Bogolyubov’s method together with Lyapunov reduc…
This paper examines whether the Lee model can be formulated in Hamiltonian terms by replacing the formal divergent Hamiltonian with a self-adjoint extension of its restriction to vectors annihilated by the interaction. The analysis shows that in the three-dimensional model, within the ordinary Hilbe…
This note addresses a conjecture arising in the use of Sobolev embedding theorems, namely that every bounded domain satisfying the cone condition can be expressed as a finite union of domains star-shaped with respect to balls. The proof establishes a compactness-type lemma: if a bounded domain is co…
This paper investigates phase transformations of indium antimonide under true hydrostatic pressure, motivated by discrepancies in earlier quasihydrostatic measurements and by the expectation of dense high pressure modifications in zinc blende type semiconducting compounds. Single crystal and polycry…
Proton nuclear magnetic resonance was used to study the mobility and diffusion of water molecules in a natural single crystal of natrolite, a zeolite whose channels contain alternating sodium atoms and water molecules. Temperature-dependent spectra show a direct transition near 135 to 180 °C from a …
The paper proves that any twofold continuous decomposition of a generalized homological cube must contain a singleton element, so a strictly twofold continuous decomposition is impossible. Arguing by contradiction, it analyzes the conjugacy relation of paired points, constructs a transfinite stratif…
This note studies harmonic functions in the unit disk and in the upper half-plane whose boundary values belong to an \(L_p\) space, estimating how far the harmonic extension deviates from its boundary function as the interior point approaches the boundary. For the disk, the deviation is bounded in t…
Electron paramagnetic resonance was used to examine anhydrous copper salts of propionic, n-butyric, n-valeric, n-caproic, and n-capric acids in polycrystalline form and, for several salts, in solutions of the corresponding anhydrous fatty acids. Measurements at 9320 MHz at room temperature and 77 K …
This study examines how induced radioactivity affects the electrode potentials and corrosion behavior of Armco iron and steel-2 in distilled water and in aqueous sodium nitrite and sodium benzoate inhibitor solutions. Neutron-irradiated samples containing Fe-59 were compared with inactive controls b…
This study examines the interconversion of 1-, 2-, and 5-methylcyclopentadienes, focusing on the hindered thermodynamic equilibrium among isomers differing in the positions of intracyclic double bonds. 5-Methylcyclopentadiene was obtained by low-temperature alkylation of cyclopentadienylmagnesium br…
Paramagnetic absorption was measured by the Q-meter method in solid vanadyl sulfate hydrate and in aqueous vanadyl sulfate solutions over several concentrations and radiofrequencies. Spin-lattice relaxation times and internal-field constants were determined from two-frequency susceptibility measurem…
This study examines the synthesis of organosilicon derivatives of furylcarbinols and substituted furfuryl alcohols, extending earlier work on furfuryloxysilanes. Trialkylchlorosilanes were reacted with furylalkyl and furylaryl carbinols in the presence of pyridine, and hydrosilanes were reacted with…
The paper analyzes the stability of a cylindrical plasma jet in a magnetic field using magnetohydrodynamic equations for stationary helical flows of an ideally conducting incompressible fluid. It derives linearized equations and boundary conditions for helical waves in a plasma cylinder, then examin…
The paper studies boundary behavior of homeomorphic Q-quasiconformal mappings of an n-dimensional ball onto a domain, aiming at an analogue of Koebe’s theorem on attainable boundary points. Using modulus estimates for curve families, including lower bounds for curves joining connected sets in the ba…
This note studies asymptotic lines on regular surfaces in Euclidean three-space with negative Gaussian curvature that varies slowly relative to a constant value. It proves estimates generalizing the Chebyshev property known for constant negative curvature: in an asymptotic quadrilateral, the sums of…
This note studies the category of representations of the group of second order unimodular matrices over a finite field of odd characteristic, associated with its unipotent subgroup. Using induced representations from additive characters, it describes the corresponding intertwining rings and spaces, …
This paper examines the possible multiple production of nucleon and antinucleon pairs by thermal photons in an open cosmological model filled with equilibrium radiation. Using detailed balance for the inverse of two-photon annihilation, it estimates the probability of single and multiple pair creati…
This paper investigates the equilibrium solubility of hydrogen in liquid iron over the high-temperature range relevant to arc welding and arc remelting, extending measurements from near the melting point toward the boiling point. Armco iron samples were melted and superheated in controlled hydrogen …
The paper studies the chromatic number of a finite undirected graph through orientations of its edges and Boolean powers of the resulting adjacency matrix. It proves that the chromatic number equals one more than the largest integer such that every orientation contains a directed path of that length…
This paper examines the preparation of alkylmagnesium and arylmagnesium halides directly from halides and magnesium in hydrocarbon media without ether or other Grignard catalysts, addressing earlier conflicting reports that such reactions were slow or of little preparative value. The authors systema…
This note extends work of Mineev on Diophantine equations with exponential terms to equations involving powers of a nonsingular integral matrix. It obtains an asymptotic formula, with a remainder term, for the number of solutions in a finite interval to a matrix Diophantine equation containing vecto…
Ethylene polymerization was studied using the soluble organometallic catalytic system tetraphenyltin, aluminum chloride, and vanadium tetrachloride in cyclohexane at 65 °C under near atmospheric pressure. The work examines the behavior of this homogeneous catalyst, including the influence of compone…
This study examines how the shift of the point of zero charge and adsorption phenomena affect the electroreduction of anions on dropping thallium amalgam electrodes. Polarographic and differential capacitance measurements were made for peroxydisulfate, ferricyanide, and tetrachloroplatinate anions o…
This paper reports an experimental determination of the surface tension of molten neodymium, motivated by the absence of experimental data for testing theoretical estimates of lanthanide surface energies. Neodymium was purified by vacuum filtration to remove oxides, then measured under high vacuum u…
This note studies general boundary value problems for properly elliptic systems in a smooth bounded multidimensional domain, allowing boundary operators whose coefficients are singular integral operators as well as ordinary differential operators. Using the Lopatinskii condition, the authors formula…
