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
The paper solves a problem posed by S. N. Bernstein on the least uniform deviation from zero of trigonometric polynomials of degree at most n with prescribed sine and cosine coefficients at a fixed harmonic h. Reducing the question to maximization of the first cosine coefficient over normalized trig…
This study addresses the lack of general, selective methods for converting gem-dihalocyclopropanes, formed by addition of dichloro- or dibromocarbenes to olefins, into cyclopropane hydrocarbons. Several reducing systems were compared, and sodium in liquid ammonia at low temperature was found to redu…
This study investigates the occurrence and relaxation kinetics of photoconductivity in two acetylene polymers with conjugated bond systems, using thin polymer layers on quartz substrates with platinum comb electrodes under modulated mercury-lamp illumination. Photocurrents of about 10^-10 to 10^-12 …
This paper studies conjugate functions of two variables and the summability of double Fourier series, extending questions known for one-dimensional conjugate functions. It establishes sharp logarithmic integrability conditions for the summability of double conjugate functions, including examples sho…
This study examines how changes in the symmetry of paramagnetic complexes affect proton transverse relaxation time in aqueous solutions. Using the spin echo method at about 17 MHz, the authors measured proton T2 as a function of pH for halide and nitrate salts of copper, cobalt, nickel, iron, mangan…
This study examines the activation energies associated with dark conductivity and photoconductivity in amorphous layers of pure chlorophyll a under high vacuum and oxygen atmospheres. Photocurrents were measured as functions of black-body source temperature, layer temperature, illumination level, an…
This paper examines the kinetics and possible mechanism of propyl gallate autooxidation by molecular oxygen in aqueous borate buffer, motivated by the biological significance of phenolic inhibitors and their radical oxidation products. Propyl gallate consumption was monitored polarographically over …
This study examines the role of sulfur vapor transport in the formation of the porous inner layer of sulfide scale produced when copper reacts with sulfur. Dense sulfide scale layers formed on copper were separated under conditions in which one side contacted sulfur and the other bordered vacuum, an…
The study examines photo-semiconductor behavior in monomeric metal acetylides with triple bonds, extending earlier work on polymeric and oligomeric polyynes. Using diffusion photo-emf and transverse photoconductivity measurements in air and vacuum, the authors investigated copper and silver phenylac…
This paper reports the preparation and characterization of lanthanum ditelluride, LaTe2, a rare-earth metal ditelluride for which little prior information was available. Single crystals were obtained by a chemical transport reaction using powdered LaTe2 and iodine, with transport from 950 to 800°C o…
This study applies electron paramagnetic resonance to the oxidation of ortho-amino-para-alkylphenols by benzoyl peroxide, motivated by the proposed radical mechanism of their antioxidant action in fuels. Benzene solutions of several aminoalkylphenols and, to isolate the role of the amino group, meth…
This note generalizes Hadamard’s three circles theorem from analytic functions of one complex variable to solutions of second order linear elliptic equations in several variables. Under uniform ellipticity, boundedness and smoothness assumptions on the coefficients, and a simplifying sign condition …
This study examines structural transformations during crystallization of amorphous isotactic polystyrene, a polymer whose slow relaxation processes make crystallization difficult and therefore suitable for observing structure formation. Amorphous particles were prepared from hot toluene and xylene s…
The study examines phase relations and solid-phase composition in the ternary system HF, UO3, H2O at 20 °C, addressing conflicting evidence on the interaction of uranyl fluoride with hydrofluoric acid. Using the isothermal solubility method over a wide range of HF concentrations, the authors analyze…
This paper extends the theory of polynomials orthogonal on the unit circle to weights supported on a finite system of arcs, allowing the weight to vanish on complementary arcs. It constructs orthogonal polynomials for special quasipolynomial weights by using rational functions on a two sheeted Riema…
This paper reports a simple synthesis of stable N-benzoyl derivatives of 1,2-dihydroquinolines, a class of compounds whose parent structures are difficult to isolate because of instability toward polymerization and oxidation. The method uses potassium bisulfate induced dehydration of readily availab…
This note develops a majorization technique for studying analytic properties of quantum mechanical scattering amplitudes in the Born expansion, using the alpha representation for diagrams generated by Yukawa-type potentials. It proves that, for negative values of the squared momentum, positivity of …
The paper studies a class of one-sided Turing machines whose input symbols are eventually converted into immutable output symbols, and characterizes the sequence operators realized by such machines. It defines A-machines, shows that the set of all such machines is not recursively enumerable, and com…
This study examines the kinetics of hydrogenation of polycyclic hydrocarbons on platinum, extending earlier work on nickel and sulfide catalysts. Seven hydrocarbons were hydrogenated with Adams’ catalyst in glacial acetic acid under low hydrogen pressure, and rate constants and apparent activation e…
This paper examines how resonance Raman scattering by molecules depends on the lifetime of electronically excited states, using diphenylpolyenes with structured absorption bands as experimental examples. Measurements of diphenyldecapentaene and diphenyldodecahexaene in acetone solutions show excepti…
This paper examines how the number and arrangement of electron donating methyl substituents affect the reactivity of cyclopropane hydrocarbons in electrophilic addition with mercury acetate. Four methyl-substituted cyclopropanes were synthesized, purified to remove olefin impurities, and reacted und…
A method is described for synthesizing polypyrazoles that contain alternating pyrazole rings with a free NH group in the polymer chain. The approach is based on the reaction of bis-diazo compounds with p-diethynylbenzene or diacetylene, giving yellow polymer powders soluble in dimethylformamide and …
This paper presents a numerical computation of the harmonic constants of the semidiurnal tidal constituent S2 for the Pacific Ocean as a whole, addressing difficulties in applying hydrodynamic tide equations to large ocean basins with open boundaries and irregular bathymetry. Using Hansen’s elliptic…
This note proves a generalization of Hilbert’s theorem on complete surfaces of constant negative curvature in three-dimensional Euclidean space. Efimov shows that no complete twice continuously differentiable regular surface in Euclidean 3-space can have Gaussian curvature bounded above by a negativ…
This paper develops a theoretical description of ideal crystal growth based on an extended phase boundary whose displacement is governed by periodic energy barriers. Generalizing earlier treatment of a planar boundary, the argument analyzes successive lower-dimensional growth processes: motion of a …
This paper examines deviations from the photochemical reciprocity law in silver halide crystals, with emphasis on whether they can arise from electronic processes alone. Using prior measurements of the photoelectret state and depolarization isopaques in AgCl, the authors relate nonreciprocity at hig…
This paper reports high resolution radio astronomical observations of Venus at a wavelength of 3.02 cm using the Pulkovo variable profile antenna near inferior conjunction in October and November 1962. The authors describe calibration of the antenna pattern and analysis of transit curves to constrai…
This paper reports the isolation and characterization of two solid modifications of cis-platodiglycine, designated alpha and beta, obtained under different crystallization conditions. The authors compare their aqueous solubilities, infrared spectra, densities, ultraviolet spectra in solution, reacti…
This study examines the X-ray L absorption spectra of lanthanum, praseodymium, neodymium, and samarium in ionic compounds including peroxides, oxides, oxyfluorides, and fluorides, with the aim of clarifying features of their electronic and valence states. Spectra were recorded photographically using…
This note studies extension of functions in \(L_p\) from an interval to a larger interval while preserving differential difference estimates expressed through moduli of smoothness. Using Steklov means and a Whitney Hestenes type reflection construction, it proves that a function with a Sobolev gener…
This paper proposes a principle for constructing combined automatic tracking systems with variable structure to improve invariance of the tracking error with respect to control actions and parameter variations. Using systems of differential equations with discontinuous right hand sides and Filippov …
This paper reports the preparation and characterization of β-hydroxyalkyl alkylene phosphites, proposed as a new type of phosphorous acid ester containing both a cyclic dioxaphospholane fragment and a free alcoholic hydroxyl group. β-Hydroxyethyl ethylene phosphite was obtained by several independen…
The study examines Michael-type additions of acrolein and mesityl oxide to difuran ketones in order to determine how conjugation and the position of the carbonyl group affect the reactivity of furan rings. Comparative experiments show that 1,5-difurylpentadien-1,4-one-3 does not react under the test…
This study examines the stability of divalent platinum diacidodiammine complexes containing ammonia or methylamine and chloride or iodide ligands, including cis and trans isomers. Overall instability constants were estimated potentiometrically at 18 °C and ionic strength one from platinum electrode …
This study examines the synthesis of polyvinyl alcohol esters containing diphenylboroxy side groups, a class of organoboron derivatives for which prior reports on polyhydric alcohols were lacking. Polyvinyl alcohol was reacted with diphenylboron chloride and its donor complexes in polar electron don…
This paper reports room temperature measurements of the electrical resistance of PbS, PbSe, and PbTe under pressures up to 200,000 kg/cm². For samples of differing purity and conductivity type, resistance first decreases to a minimum, then rises to a maximum, and subsequently decreases smoothly, whi…
This paper studies the fibration of a pair of corresponding two-parameter families of straight lines in an n-dimensional projective space, with n greater than 3, under the assumption that one family has two distinct focal surfaces. Using a moving projective frame and exterior differential forms, the…
This paper examines the acid-catalyzed condensation of enamines with aldehydes, focusing on N-propenylpiperidine and propionaldehyde as a model system. Two possible mechanisms are compared: formation of an imonium ion followed by condensation, and direct acid-assisted addition of the aldehyde to the…
This paper studies optimal stopping for Markov processes, where one chooses a Markov time to maximize the expected reward from stopping, possibly after subtracting an additive observation cost. For countable discrete Markov chains, the problem is reduced to the zero-cost case and characterized throu…
This paper examines the mechanisms of spin-lattice relaxation in magnetically diluted free radicals in frozen and liquid solutions using electron paramagnetic resonance saturation measurements. For supercooled solid solutions of DPPH and tetramethyl nitroxide radicals, the measured relaxation times …
This study examines how the surface concentration of anthracene adsorbed from vapor on aluminosilicate gel affects its optical absorption and electron paramagnetic resonance spectra. Samples were prepared under vacuum with varied adsorption times, and their diffuse-reflectance absorption and EPR spe…
This study investigates the retention and release of molecular hydrogen formed during low-temperature radiolysis of solid paraffin and high-pressure polyethylene near liquid-nitrogen temperature. Using electron irradiation, manometric measurements, mass spectrometry, and diffusion-equation analysis,…
This study examines the spectral sensitivity and sign of photopotentials generated in metal-free and magnesium phthalocyanine layers in contact with aqueous electrolytes, including media containing oxidizing or reducing molecules. Using an electrolytic capacitor arrangement with intermittent monochr…
This paper analyzes the motion of a free gyroscope in a Cardan suspension on a moving base while accounting for the masses of the suspension rings. It derives general kinematic relations, kinetic energy expressions, and Lagrange equations without assuming small ring angles, then applies small-deviat…
This note generalizes Sherman’s method for plane doubly connected domains to spatial boundary value problems in domains bounded by two Lyapunov surfaces. For the Dirichlet and Neumann problems of potential theory, auxiliary boundary data are introduced on one surface and combined with simple or doub…
The study examines ultraviolet and visible absorption spectra of selected alkyl, dialkyl, acyl, and diacyl derivatives of ferrocene, addressing inconsistencies and limited comparability in earlier spectral data. Purified compounds were measured in isooctane solutions from 300 to 700 mµ at room tempe…
This paper addresses the calculation of spectroscopic masses for hydrogen and deuterium in isotopic molecules, with particular attention to how anharmonicity is represented in nonquantum molecular vibration theory. Starting from secular equations using either zero frequencies or spectroscopic masses…
This note studies functions in local L2 on the real line whose translates generate a proper closed subspace, focusing on the case where the associated exponential spectrum is regular. It gives necessary and sufficient conditions for a function to be regular in terms of periodicity in the mean with r…
This note studies the use of the Fourier method for a mixed initial boundary value problem for a class of quasilinear hyperbolic equations with a self-adjoint elliptic spatial operator and homogeneous boundary condition. The authors reduce the problem to a countable system of nonlinear integro-diffe…
This paper studies expansions in eigenfunctions for a family of non-selfadjoint singular second-order differential operators on the half-axis, generated by a complex potential and a boundary condition whose coefficient is a rational function of the spectral parameter. Using Naimark’s method, it desc…
