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 develops new estimates for rational trigonometric sums and applies them to problems concerning the Riemann zeta function and the distribution of prime numbers. Combining Vinogradov’s method with an approach that exploits the rational structure of the sums, it proves a strengthened bound f…
This paper studies when continuous complex functions on plane sets can be uniformly approximated by functions analytic in a neighborhood, using analytic capacity and harmonic capacity to measure the size of complements locally. It proves a basic approximation lemma that replaces Cauchy kernels by fu…
This paper investigates whether hydrocarbons and oxygen-containing compounds formed from carbon monoxide and hydrogen on fused iron catalysts arise through related mechanisms rather than independent pathways. The authors added carbon-14 labeled butanol and methanol to synthesis gas under high-pressu…
This paper reports the synthesis of 2-methyl-4,5-thiopheno(2′,3′)thiazole as part of an investigation of isosterism between the groups CH=CH and S in fused thiazole systems. The authors prepared 2-thioacetylaminothiophene from 2-acetylaminothiophene using phosphorus pentasulfide and examined its oxi…
This paper constructs fundamental matrices of solutions for general linear systems that are parabolic in the sense of Petrovskii, extending earlier work on systems first order in time. Under boundedness, Hölder continuity, and related regularity assumptions on the coefficients, it establishes existe…
This note studies the relation between Chebyshev sets, defined by existence and uniqueness of best approximations, and convex sets in Banach spaces. It gives geometric criteria involving the unit sphere, especially strict convexity and absence of conical points, and proves that in a finite-dimension…
This paper studies boundary value problems for uniformly elliptic quasilinear first order systems in the plane, written in complex form with coefficients measurable in the independent variable and Lipschitz or controlled in the dependent variable. The boundary condition is reduced to a canonical for…
This note develops a mathematical framework for current monitoring of abstract transformers treated as black boxes, where correct operation at selected input signals changes the estimated probability of correct operation on an interval. It introduces a control operator, definitions of reliability an…
This paper describes a synthetic route to unbranched polyene aldehydes and ketones through zinc chloride catalyzed condensation of aldehyde acetals with vinyl ethyl ether or isopropenyl ethyl ether, followed by hydrolysis. Successive chain extension of crotonaldehyde and sorbic aldehyde acetals with…
This study examines the passivation and anodic protection of VT-1D titanium in sulfuric acid solutions, where corrosion resistance decreases at concentrations above about 10 percent. Using surface abrasion under solution, potential measurements, anodic polarization curves, and gravimetric corrosion …
This study investigates how stresses are distributed and change during fracture in several polymers, using high speed cinematography in polarized light to visualize birefringence in deformed transparent specimens. Polyethylene, polymethyl methacrylate, and vulcanized natural rubber films were stretc…
This paper studies best Chebyshev approximation of continuous functions on a compact set with values in an infinite-dimensional commutative Hilbert ring by generalized polynomials with coefficients in that ring. Using the decomposition of ring elements into orthogonal idempotents and an operator-fun…
This study examines the adsorption of benzene vapor on palladium films prepared by high vacuum sublimation, motivated by kinetic studies of cyclohexadiene disproportionation on palladium. Using a flow method, adsorption isotherms were measured at 20 and 79 degrees, with corrections for adsorption on…
This paper applies Bogolyubov’s variational principle to a model Hamiltonian used in the theory of superconductivity, reformulating the pair excitation operators in terms of spin variables and reducing the problem to an Ising-like approximate Hamiltonian. By minimizing an upper bound for the free en…
This paper examines the recrystallization behavior of cast tantalum subjected to cold rolling and subsequent vacuum annealing, addressing the lack of published recrystallization data for tantalum produced by casting. Arc-melted tantalum specimens were forged, annealed, cold rolled to varying reducti…
The paper analyzes the phonon contribution to thermal conductivity in superconductors in the temperature range where electron, phonon interaction is an important scattering mechanism. Using the superconducting quasiparticle transformation and a kinetic equation for the phonon distribution, the autho…
The paper studies saturation classes for linear summation processes associated with Fourier expansions in spaces of periodic functions, including continuous functions and \(L_p\) spaces. Using an elementary method attributed to Favard, it proves a general criterion: when the normalized multiplier de…
This study examines whether the tendency of methyl-substituted nitrogen heterocycles and their quaternary salts to undergo condensation reactions is governed by the ease of proton removal from methyl groups. Hydrogen isotope exchange with methanol-d in the presence of triethylamine was measured for …
This note extends inverse theorems from the constructive theory of periodic functions of one variable to functions of several variables. It establishes estimates for mixed finite differences of multivariable periodic functions in terms of best approximation by trigonometric polynomials of prescribed…
The paper develops a generalized solution theory for the mixed initial-boundary value problem for a general second order linear hyperbolic equation on a bounded star-shaped spatial domain, with right-hand side taken from a negative Sobolev-type Hilbert space. It defines suitable function spaces and …
This paper studies the general integral equation governing neutron slowing down in a spatial domain with absorbing boundaries, sources, boundary influx, absorption, and scattering by nuclei of varying mass. The neutron state is formulated in phase space using position, direction, and lethargy, and t…
This note studies the decomposition of tensor products of infinite-dimensional principal series representations of the proper Lorentz group, formulated through the locally isomorphic group of complex second-order matrices with determinant one. It first gives a unitary transformation showing that suc…
The study examines the kinetics of isoprene polymerization initiated by a complex catalyst formed from titanium tetrachloride and triisobutylaluminum, using calorimetric measurement of heat evolution to avoid complications from insoluble polymer deposits. Polymerization with a preformed catalyst beg…
This paper examines whether an eight-component nickel alloy system containing chromium, tungsten, molybdenum, niobium, titanium, aluminum, and carbon can be treated as a quasibinary equilibrium between a six-component nickel solid solution and titanium carbide. Guided by carbide formation heats, the…
This study examines the use of gamma irradiation to promote reactions between metallic tin and alkyl halides, a class of organometallic transformations that normally requires high temperatures and gives impure products. Using cobalt-60 irradiation at near room temperature, the authors show that alky…
This paper examines the acylation of aromatic nuclei by acid chlorides in the presence of powdered copper, molybdenum, and tungsten, as an alternative to conventional Friedel-Crafts conditions using aluminum chloride. Aromatic compounds were heated with acid chlorides at 90 to 150 °C, and the reacti…
This paper formulates preliminary results on the analytic capacity of bounded plane sets, introduced in connection with the representation of continuous functions by uniformly convergent series of rational functions. It defines analytic capacity through bounded analytic functions on the complement o…
This article examines the use of radical-induced polyrecombination as a method for preparing high-molecular-weight compounds from saturated starting materials. Using n-diisopropylbenzene and chiefly tert-butyl peroxide, the authors study how peroxide concentration affects conversion, molecular weigh…
This study examines the alkylation of naphthalene, beta-methylnaphthalene, and tetralin with acetylene using phosphoric acid, boron trifluoride catalyst in different solvents. Although naphthalene did not react in alcoholic solution, alkylation proceeded in chloroform or carbon tetrachloride at abou…
This paper analyzes fluctuations of the amplitude and phase of short waves propagating through a locally isotropic turbulent medium whose turbulence intensity varies smoothly along the propagation path. Using a spectral representation of refractive-index fluctuations with a position-dependent struct…
This paper studies the Cauchy problem for square systems of linear partial differential equations whose coefficients depend only on time, reducing the system to first order in time and analyzing it after Fourier transformation in the spatial variables. It gives conditions on the fundamental solution…
This study examines how structural features of organic luminescent molecules affect the probability of transition to a metastable state, estimated from the ratio of phosphorescence to fluorescence quantum yields as a function of the fluorescence maximum. Using comparative data for substituted phthal…
This paper reports an optical study of polymethyl methacrylate, or plexiglas, compressed by a strong shock wave, addressing the difficulty of determining temperature and heat capacity in dense shocked solids and liquids from hydrodynamic measurements alone. Radiation from the shock front was recorde…
This paper addresses the correction required in estimating direct electron positron pair production by high energy electrons in nuclear emulsions, where bremsstrahlung photons converting near the electron track can imitate true trident events. The authors calculate the number of such pseudotrident e…
This paper investigates the temperature dependence of Faraday rotation and related microwave properties in nickel magnesium ferrites of composition Ni1-xMgxFe2O4 at a wavelength of 3.2 cm. Using a waveguide apparatus with controlled cooling and heating, the authors measured the rotation angle of the…
This paper investigates the preparation and properties of silicic acid solutions in acetone, motivated by the need for stable concentrated binders for refractory coatings in investment casting. Silicic acid was extracted from acid-neutralized liquid glass by mixing with acetone and salting out with …
The paper examines the focusing of rectilinear charged-particle beams by rapidly varying electromagnetic fields, including high-frequency systems that are not reducible to static focusing by a change of reference frame. Using a nonrelativistic equation of motion and averaging over the period of the …
This study examines whether gem-substituted butadienes can participate in diene condensations, a question previously uncertain because such compounds were often reported to polymerize or react only after rearrangement. The authors prepared several substituted butadienes and reacted them with maleic …
This study examines how intrinsic beta radioactivity affects the sorption properties of barium sulfate precipitates. Barium sulfate samples containing sulfur 35 at specific activities from 0.01 to 10 mCi/g were prepared with comparable surface areas, then equilibrated with aqueous solutions of methy…
The study examines degenerate chain branching during liquid-phase oxidation of n-decane and evaluates whether inhibitor measurements can determine the branching rate at different reaction stages. Alpha-naphthol was introduced into oxidizing n-decane, and hydroperoxide accumulation, inhibitor consump…
This paper examines the proposed semiconductor character of reduced iron, copper catalysts for CO and hydrogen synthesis and the role of potassium carbonate as an alkaline promoter. The authors measure electrical resistance as a function of temperature for reduced and unreduced catalyst samples cont…
This paper describes a catalytic method for synthesizing tris(trialkyl(aryl)silyl)borates by dehydrocondensation of trialkyl(aryl)silanes with boric acid. The reaction is carried out at 100 to 130°C in the presence of small amounts of anhydrous cobalt, nickel, palladium, or platinum halides, with hy…
This study examines the stereochemistry of isotopic exchange reactions of organomercury salts with mercury labeled with Hg-203, distinguishing exchange with metallic mercury as homolytic substitution and exchange with mercuric halide as electrophilic substitution at saturated carbon. Using diastereo…
This paper studies linear extremal problems for weighted classes of analytic functions in finitely connected domains with rectifiable boundary, under minimal integrability assumptions on the weight. Using duality between boundary constrained classes and weighted approximation classes, it establishes…
This paper examines how thin liquid metallic coatings reduce the strength and induce brittleness in solid metals, including single crystals, and argues that the effect is not primarily due to dissolution or grain-boundary attack. Comparing experimental cases with binary melting diagrams, the authors…
This paper examines isotope effects on critical temperature by comparing eleven deuterated organic compounds with their hydrogen analogues, alongside previously reported data for inorganic substances. Critical temperatures were measured from meniscus disappearance and reappearance, with paired capil…
The paper studies Favard and Zamansky’s problem of determining saturation classes for summation methods, focusing on the Hölder method of summation applied to Fourier series of continuous periodic functions. It derives the asymptotic behavior of the Hölder multipliers and proves that the Hölder meth…
The paper studies free multiplicative semigroups of real numbers whose counting function has a power density, and asks how the distribution of their generating elements follows from the distribution of all semigroup elements. Using elementary methods modeled on the arguments of Selberg, Shapiro, Ayo…
