Showing 50 of 25456 papers

Study of Chemical Adsorption on Solid Solutions of Nickel Oxide

N. P. Keier, L. N. Kutseva
1957 SovietRxiv: ru-195701.85213

This study examines chemisorption on nickel oxide and nickel oxide solid solutions whose electronic properties are modified by dissolved lithium or iron oxides. Using pressure drop measurements and conductivity observations, the authors compare adsorption kinetics for oxygen, carbon monoxide, acetyl…

Selective Hydrogenation of Monosaccharides and Polyhydric Alcohols

A. A. BALANDIN and N. A. VASONINA
1957 SovietRxiv: ru-195701.85165

This paper examines the selective hydrogenation and hydrogenolysis of monosaccharides and polyhydric alcohols over nickel catalysts in aqueous solution under high hydrogen pressure. It critiques earlier mechanistic interpretations based on dehydrogenation or absolute free energies, and applies Balan…

Flow past a circular cylinder with a detached shock wave

Unknown
1957 SovietRxiv: ru-195701.85132

This paper formulates the problem of plane supersonic ideal-gas flow past a circular cylinder with an initially unknown detached shock wave, including boundary conditions on the body and shock. It applies the method of integral relations, replacing the flow region between the body and shock by a fin…

THE RELATIVE ROLE OF ELECTRICAL AND DIFFUSION PROCESSES IN THE PHENOMENA OF ADHESION OF TWO POLYMERS

Unknown
1957 SovietRxiv: ru-195701.85124

This study examines the relative importance of electrostatic and diffusion mechanisms in the adhesion of polymer pairs and polymer contacts with glass, metal, and filled rubbers. Using roller adhesiometry in vacuum and air, measurements of work of separation, electron emission, residual surface char…

Some Unsteady Plane and Spatial Gas Flows

Unknown
1957 SovietRxiv: ru-195701.84958

The paper studies unsteady isentropic gas flows in plane and spatial settings, with emphasis on self-similar motions in which the variables depend on spatial coordinates divided by time. Starting from the Euler equations and, for plane flows, the potential-flow formulation, it derives transformed eq…

On the Theory of Phase Transition

H=H_0+H_{int},
1957 SovietRxiv: ru-195701.84811

This paper develops an asymptotically exact calculation of the thermodynamic potential for a class of fermionic pairing Hamiltonians relevant to superconductivity, including momentum-dependent interaction kernels. Using canonical transformations and statistical perturbation theory, the authors show …

Homology of Spaces of Closed Curves

Unknown
1957 SovietRxiv: ru-195701.84677

This note studies spaces of closed rectifiable curves on a closed Riemannian manifold, with and without marked points and orientations, and relates their homology to the theory of closed geodesics. It identifies circular connectivities with mod 2 Betti numbers of appropriate curve spaces, gives form…

Investigation of the Nature of the Primary Photoreduced Form of Chlorophyll and Its Analogs Using $\mathrm{D}_2\mathrm{O}$

V. B. EVSTIGNEEV and V. A. GAVRILOVA
1957 SovietRxiv: ru-195701.84603

This study examines whether proton transfer participates in the formation of the primary photoreduced form of chlorophyll and related pigments. Using deuterium substitution in ascorbic acid, achieved by adding heavy water in pyridine solutions, the authors compared spectrophotometric and potentiomet…

On the Spectral Method for Determining the Number and Position of Side Chains in Molecules of Benzene Homologues

O. V. Bragin, V. L. Broude, S. V. Zotova, A. L. Liberman,
1957 SovietRxiv: ru-195701.84570

This study examines the use of low-temperature ultraviolet absorption spectra for identifying the number and positions of side chains in benzene homologs. Spectra of purified tri- and tetraalkylbenzenes, para-disubstituted benzenes, and alkenyl-substituted compounds were recorded in crystalline or p…

On the Relationship Between the Viscosity Coefficient and the Structure of Matter in the Liquid State

A. Z. GOLIK and D. N. KARLIKOV
1957 SovietRxiv: ru-195701.84558

This paper examines the relation between viscosity and liquid structure using isoviscous liquid metal solutions, defined as solutions with coincident viscosity, temperature curves. Zinc and cadmium solutions in mercury with paired equal viscosities were studied by X-ray scattering, with scattered in…

On Functionally Closed Spaces

Unknown
1957 SovietRxiv: ru-195701.84383

This paper studies functionally closed completely regular spaces, also known as Hewitt Q-spaces, through the behavior of continuous real-valued functions under extensions. It gives criteria for an extension to be regular in terms of closures of countable intersections of zero-sets, constructs a cano…

On Some Quasilinear Parabolic Systems

T. D. VENTSEL
1957 SovietRxiv: ru-195701.84069

The paper studies existence and uniqueness for Cauchy and first boundary value problems for one-dimensional quasilinear parabolic systems with coefficients depending on the unknown functions. Using Rothe’s method and a priori estimates for solutions and their derivatives, it proves solvability in re…

Inequalities for Polynomials and Their Derivatives

G. K. LEBED’
1957 SovietRxiv: ru-195701.84012

This note establishes several inequalities estimating derivatives of trigonometric and algebraic polynomials under pointwise or weighted norm constraints. It gives bounds for derivatives of trigonometric polynomials dominated by a nonnegative majorant with prescribed smoothness or modulus properties…

Effect of Substituents on the Properties of Monosubstituted Benzene Molecules

P. P. SHORYGIN and Z. S. EGOROVA
1957 SovietRxiv: ru-195701.83718

This study examines how substituents affect the optical, electrical, and chemical properties of monosubstituted benzenes. Using Raman line intensities near 1600 cm-1, molecular refraction exaltation, ultraviolet absorption data, dipole moment anomalies, and Hammett constants, the authors compare a b…

Study of Aqueous Solutions of Sodium Paratungstate

Water plays an important constitutional role in the compound obtained (²—⁴).
1957 SovietRxiv: ru-195701.83663

This study examines transformations of tungstate anions in aqueous sodium paratungstate and acidified sodium tungstate solutions, especially the effects of pH, heating, and aging. Using dialysis, polarography, ultraviolet absorption spectroscopy, chromatography, and anion-exchange behavior, the auth…

Temperature Dependence of the $g$-Factor and Relaxation Times in Ferromagnetic Resonance for Some Ferrites

Unknown
1957 SovietRxiv: ru-195701.83530

This paper reports measurements of the temperature dependence of the spectroscopic splitting factor and relaxation time in ferromagnetic resonance for several sintered lithium zinc and nickel zinc ferrites. Using absorption and dispersion curves at about 9.4 GHz, together with resonance formulas acc…

Synthesis of $5$-methoxyindole derivatives

Derivatives of 5-hydroxyindole, which underlies the structure of serotonin
1957 SovietRxiv: ru-195701.83393

This paper reports the synthesis of 5-methoxyindole derivatives related to 5-hydroxyindole, a structural element of serotonin and of compounds of interest as serotonin antimetabolites. A series of 2-aryl-5-methoxyindoles was prepared by condensing p-anisidine with substituted omega-haloacetophenones…

Activation Energy of the Elementary Reaction $\mathrm{RO}_2+\mathrm{RH}$ in the Oxidation of n-Decane

Unknown
1957 SovietRxiv: ru-195701.83148

This paper estimates the activation energy of the elementary chain propagation reaction between peroxy radicals and hydrocarbon molecules in the liquid phase oxidation of n-decane. Because hydroperoxide decomposition occurs concurrently with hydroperoxide formation, the authors derive a kinetic rela…

On the Radial Displacement of Gas-Saturated Oil by Water

Unknown
1957 SovietRxiv: ru-195701.83029

The paper formulates a generalized model for radial displacement of gas-saturated oil by water in a circular reservoir, allowing for pressure-dependent oil and gas properties, deviations from ideal gas behavior, and changes in oil formation volume factor during degassing. Using material-balance rela…

ON A MECHANICAL TRANSFORMER

![Fig. 1 and Fig. 2](image)
1957 SovietRxiv: ru-195701.82841

This paper presents the theory of a two-degree-of-freedom kinematic chain that transforms the path of one point into the path of another. It derives the coordinate relation for the transformer, \(x=\xi\) and \(y=\xi^2/\eta\), and shows that the transformation is reversible. Several cases are analyze…

On Polymerization in Viscous Media

I. A. Arbuzova, V. N. Efremova, and I. K. Ulezlo
1957 SovietRxiv: ru-195701.82819

This study examines how solvent viscosity affects radical polymerization rates and polymer molecular size for acrylamide, methacrylamide, and methylolmethacrylamide. The authors compare ultraviolet initiated polymerization in water with polymerization in highly viscous glycerin, measuring conversion…

Distribution Functions for a Classical Electron Gas

Unknown
1957 SovietRxiv: ru-195701.82810

This paper addresses the construction of the radial distribution function for a classical electron gas with Coulomb interactions, focusing on the failure of the standard Debye expansion at short distances where it can become negative. The authors reformulate Bogolyubov’s integral equations by factor…

ON THE QUESTION OF CONJUGATION IN BUTADIENE

Unknown
1957 SovietRxiv: ru-195701.82736

The paper examines the interpretation of conjugation and dual electrophilic addition in butadiene-1,3, focusing on the mesomeric and electromeric explanation associated with Ingold’s theory. It compares structural and spectroscopic evidence, especially C-C and C=C bond distances and vibrational freq…

On the compound $\mathrm{Ni}_3\mathrm{B}$ in nickel–boron alloys

N. I. BLOK, M. N. KOZLOVA, N. F. LASHKO, and K. Ya. SHPUNT
1957 SovietRxiv: ru-195701.82597

This paper examines the phase composition of nickel-boron alloys containing 0.01 to 2.5 percent boron, with particular attention to the nickel-rich boride reported as Ni3B. The authors used metallographic observation, chemical and electrolytic isolation of precipitated phases, chemical analysis, and…

Exact Solution of a Nonlinear Problem of an Explosion in a Gas with Variable Initial Density

V. P. KOROBEINIKOV
1957 SovietRxiv: ru-195701.82579

This note gives an exact solution for the one-dimensional adiabatic motion produced by an instantaneous release of finite energy in a gas whose initial pressure is constant and whose initial density varies with distance according to a specified parametric law. The problem is formulated for spherical…

Passivation and Depassivation of a Lead Anode in Concentrated Hydrofluosilicic, Perchloric, and Fluoroboric Acids

Unknown
1957 SovietRxiv: ru-195701.82456

This study examines the passivation and depassivation of lead anodes in concentrated fluosilicic, perchloric, and fluoboric acids at low temperatures, with attention to critical current density, acid concentration, temperature, and stirring. Measurements of anode potential and current show that pass…

On nonanalytic solutions of the Goursat problem for a system of differential equations with two independent variables

Unknown
1957 SovietRxiv: ru-195701.82148

This note studies the Goursat problem for first order hyperbolic systems of differential equations with two independent variables, with data prescribed on straight lines and with solutions not assumed analytic. Using reduction to characteristic variables and Mellin transform methods, it derives crit…

ON THE METHOD OF LINES FOR CERTAIN BOUNDARY-VALUE PROBLEMS FOR SYSTEMS OF PARTIAL DIFFERENTIAL EQUATIONS

Unknown
1957 SovietRxiv: ru-195701.82097

This note proves convergence and derives error estimates for the method of lines applied to several boundary value problems for systems of partial differential equations. A general lemma relates the approximation error to the norm of the inverse differential difference operator and the consistency e…

ON THE EQUICONVERGENCE OF FOURIER–CHEBYSHEV AND MACLAURIN EXPANSIONS OF ANALYTIC FUNCTIONS OF THE CLASS \(H_2\)

Unknown
1957 SovietRxiv: ru-195701.81941

The paper studies uniform equiconvergence on arcs of the unit circle between Fourier-Chebyshev expansions in orthonormal polynomials with respect to a weight and the ordinary Maclaurin expansion for analytic functions in the Hardy class H2. It proves that, under local positivity and a Dini-Lipschitz…

On the Classification of Secondary Luminescence

Academician of the Academy of Sciences of the BSSR B. I. STEPANOV and P. A. APANASEVICH
1957 SovietRxiv: ru-195701.81806

This paper examines how secondary luminescence should be classified, questioning the sufficiency of Vavilov’s criteria based on quenching and afterglow duration. Using a classical dipole model and a quantum electrodynamic treatment of a three-level atom interacting with a medium, it compares station…

Study of the mechanism of alkylation of alcohols with $\mathrm N$ -trimethyl- $\alpha$ -phenethylammonium iodide

Unknown
1957 SovietRxiv: ru-195701.81693

This paper examines the mechanism of alcohol alkylation by optically active N-trimethyl-alpha-phenethylammonium iodide, focusing on whether transfer of the alpha-phenethyl group occurs synchronously or through an intermediate carbonium ion. Methyl, ethyl, and n-butyl alcohols were reacted with the a…

Kinetics of Isotopic Exchange of Sulfate Ions in Aqueous Solutions of Ammines and Aquoammines of Trivalent Cobalt

Ya. A. FIALKOV and V. D. PANASYUK
1957 SovietRxiv: ru-195701.81691

The study examines the kinetics of sulfate ion isotopic exchange between outer and inner coordination spheres in aqueous solutions of sulfatoaquotetramminecobalt(III) sulfate and sulfatopentamminecobalt(III) sulfate, using sulfur-35 labeled sodium sulfate and separation of sulfate forms with benzidi…

On the Stereochemistry of Catalytically Active Complexes

A. A. BALANDIN and E. I. KLABUNOVSKII
1957 SovietRxiv: ru-195701.81690

This paper investigates the stereochemistry and sequence of catalytic hydrogenation of a triptycene-derived dione over skeletal nickel in dioxane at 45 degrees. Guided by multiplet theory, the authors test whether hydrogenation first affects the olefinic bond or the carbonyl groups by interrupting t…