Showing 50 of 25456 papers

On the Uniqueness of the Solution of Approximate Boundary Value Problems in the Dynamics of an Incompressible Fluid with Variable Viscosity

S. A. REGIRER
1957 SovietRxiv: ru-195701.58583

This note addresses uniqueness for the boundary value problems arising in successive approximations to the dynamics and heat exchange of an incompressible fluid whose viscosity varies with temperature. For prescribed viscosity, it proves uniqueness of the velocity field, with pressure determined up …

ON THE INFLUENCE OF INITIAL IMPERFECTIONS ON THE STABILITY OF CYLINDRICAL SHELLS UNDER EXTERNAL PRESSURE

Unknown
1957 SovietRxiv: ru-195701.58288

This paper examines how initial geometric imperfections affect the large-deflection stability of a hinged circular cylindrical shell under uniform external pressure. Using a Ritz approximation for the shell deflection that includes circumferential waves, inward bulging, and radial displacement of th…

Operational calculi for functions defined on the whole line

V. A. DITKIN
1957 SovietRxiv: ru-195701.58198

This paper develops an operational calculus for functions defined on the whole real line under local integrability and two-sided Laplace convergence assumptions. It constructs a quotient space from pairs of right and left Laplace transforms and proves that this space is linearly isomorphic to the or…

AN ATTEMPT AT COMPUTING A POTENTIAL FUNCTION IN THE LOWER HALF-PLANE FROM ITS VALUES MEASURED ON THE EARTH’S SURFACE

Unknown
1957 SovietRxiv: ru-195701.58172

This paper examines the downward continuation of gravitational and magnetic potential fields from measurements on the earth’s surface, noting limitations in commonly used mean value and Renvoy formulas and deriving an error term for the latter. It proposes instead to continue suitable analytic funct…

Synthesis of Polyorganoalumosiloxanes. Metathesis Reaction of Sodium Salts of Alkylsilanetriols and Aluminum Chloride

K. A. Andrianov and A. A. Zhdanov
1957 SovietRxiv: ru-195701.58163

This paper investigates the synthesis of polyorganoalumosiloxanes through metathesis reactions between aluminum chloride and sodium salts of alkylsilanetriols or related organosiloxane salts. The authors argue that an anhydrous alcoholic medium favors salt exchange with precipitation of sodium chlor…

Hydrogen adsorption on nickel layers condensed in high vacuum

N. N. KAVTARADZE
1957 SovietRxiv: ru-195701.58098

This study examines hydrogen adsorption on high-purity nickel layers condensed in high vacuum, using gas admission and capillary flow methods over temperatures from minus 195 to 100 degrees Celsius and low pressures. The experiments distinguish two components of adsorption: a rapid irreversible upta…

On the Approximation of Certain Classes of Continuous Functions by Fourier Sums and Fejér Sums

A. V. Efimov
1957 SovietRxiv: ru-195701.58081

The paper studies uniform approximation of classes of continuous periodic functions, defined by Weyl derivatives and moduli of smoothness, by partial Fourier sums and Fejér sums. It formulates two related problems: determining principal terms of approximation errors uniformly over a function class, …

Generalization of Some Results of S. M. Nikol'skii and A. F. Timan

Unknown
1957 SovietRxiv: ru-195701.58075

The paper studies the uniform asymptotic behavior of the maximal deviation between functions in Hölder classes on a finite interval and truncated arithmetic means of their Chebyshev series partial sums. Extending earlier results for ordinary partial sums, it analyzes the quantity obtained by taking …

On Classes of Models with a Generation Operation

A. I. MAL'TSEV
1957 SovietRxiv: ru-195701.57915

The paper studies how the algebraic notion of generation can be extended to abstract classes of first order models, focusing on classes in which intersections of submodels yield natural generated submodels. It introduces pseudoaxiomatizable classes and proves that, for such classes with natural gene…

A Comparative Study of Ordering Arising in Polymers during Their Crystallization or Orientation of Chain Molecules

Unknown
1957 SovietRxiv: ru-195701.57848

This paper examines how order develops in chain polymers through crystallization and through orientation of molecular chains, arguing that diffraction patterns should not be interpreted as evidence of crystallinity without separating these contributions. Using electron and X-ray diffraction, the aut…

On complete systems and bases in $L_2$

Yu. A. KAZ’MIN
1957 SovietRxiv: ru-195701.57720

This paper studies completeness and basis properties in the Hilbert space \(L_2\) for systems of functions that are close to known complete systems. It proves a general operator criterion: an invertible bounded linear transformation preserves completeness and basis properties, then applies it to per…

Study of the Interaction Between Ammonia and Zinc Chloride in an Aqueous Medium

G. G. URAZOV, A. K. KIRAKOSYAN, and R. S. MKHITARYAN
1957 SovietRxiv: ru-195701.57586

This study examines the interaction of zinc chloride with ammonia in aqueous solution across the ammonia concentration range, using isothermal solubility measurements and chemical analysis of liquid and solid phases. The system is shown to pass through two crystallization regions: at lower ammonia c…

On the preparation of acetone cyanohydrin ( $\alpha$ -hydroxyisobutyronitrile) from acetone and sodium cyanide

Unknown
1957 SovietRxiv: ru-195701.57154

The paper investigates a method for preparing acetone cyanohydrin from acetone and sodium cyanide using the sulfur dioxide molecular compound of acetone in the presence of controlled water. Experiments show that the reaction proceeds smoothly below 25°C, with sodium sulfite heptahydrate precipitatin…

Association States of Selenium in the Gas Phase

Unknown
1957 SovietRxiv: ru-195701.57107

This study reexamines the molecular association states of selenium vapor, addressing discrepancies between earlier vapor-density interpretations and equilibrium calculations for elemental selenium. Vapor densities were measured by a static method in quartz apparatus over 550 to 900 degrees Celsius a…

On the Behavior Near the Boundary of Derivatives of Certain Sequences of Analytic Functions Uniformly Convergent Inside the Domain

G. Ts. Tumarkin
1957 SovietRxiv: ru-195701.57036

The paper studies sequences of analytic functions in the unit disk that satisfy the Khinchin and Ostrowski hypotheses, namely a uniform logarithmic integral bound and convergence of angular boundary values on a set of positive measure. Using a previous subsequence extension theorem together with res…

New Data on the Polymorphism of Sodium Carbonate

Unknown
1957 SovietRxiv: ru-195701.56808

This study reexamines the polymorphism of anhydrous sodium carbonate, focusing on phase changes as functions of temperature and sample history. Using high-temperature X-ray powder diffraction and differential thermographic analysis on samples subjected to melting, calcination, drying, and storage, i…

On Semi-Reducible Riemannian Spaces

G. I. KRUCHKOVICH
1957 SovietRxiv: ru-195701.56715

The paper studies semi-reducible Riemannian spaces, whose metric can be written as a sum of an independent principal metric and a conformally scaled additional metric. It gives a geometric characterization in terms of two mutually orthogonal foliations, one totally geodesic and the other umbilical w…

Universal Relation Between the Absorption and Luminescence Spectra of Complex Molecules

Academician of the Academy of Sciences of the BSSR B. I. STEPANOV
1957 SovietRxiv: ru-195701.56592

This paper derives a general relation connecting the absorption and luminescence spectra of complex molecules, motivated by earlier observations of mirror symmetry between absorption and emission bands. Assuming rapid thermal equilibration among vibrational sublevels in the excited electronic state …

Determination of the potential of zero charge of lead dioxide electrodes by hardness measurement

D. I. LEIKIS and E. K. VENSTREM
1957 SovietRxiv: ru-195701.56392

This study applies pendulum hardness measurements to determine the potential of zero charge of lead dioxide electrodes in sulfuric acid solutions, motivated by the difficulty of direct measurements on solid oxide electrodes in concentrated electrolytes. Lead dioxide deposits prepared by anodic oxida…

DIFFUSION OF A VORTEX LAYER AND HEAT TRANSFER

Unknown
1957 SovietRxiv: ru-195701.56364

This paper studies an automodel problem for diffusion of a vortex layer and heat transfer in a half-space liquid whose viscosity, thermal conductivity, and heat capacity may depend on temperature. The governing momentum and energy equations, including viscous dissipation, are reduced by dimensional …

ON THE REDUCIBILITY OF ONE CLASS OF SYSTEMS OF DIFFERENTIAL EQUATIONS WITH QUASIPERIODIC COEFFICIENTS

Unknown
1957 SovietRxiv: ru-195701.56307

This paper studies reducibility for a class of two-dimensional linear systems of differential equations with quasiperiodic coefficients, a problem complicated by small divisors and by the behavior of indefinite integrals of almost periodic functions. It introduces corresponding majorant series to es…

Synthesis of Trialkylbutadienylsilanes

S. I. Sadykhzade, I. V. Avgushevich
1957 SovietRxiv: ru-195701.56198

This paper investigates routes to trialkylbutadienylsilanes, focusing on the synthesis of 1-trialkylsilylbutadienes from secondary unsaturated alcohols. An attempted direct synthesis from chloroprene and a copper, silicon alloy failed because chloroprene cyclodimerized before reaction, whereas Grign…

The Role of the Gas Environment in Coal Fracture Processes

I. L. ETTINGER, E. G. LAMBA, and V. G. ADAMOV
1957 SovietRxiv: ru-195701.56185

This study examines how gaseous media influence the mechanical destruction of fossil coals, with attention to natural structural disturbance, metamorphic degree, and gas type. More than 100 coal samples were crushed in air, carbon dioxide, and methane at elevated pressure, and the resulting dust yie…

Fine structure of $\alpha$-decay of even-even nuclei

V. G. NOSOV
1957 SovietRxiv: ru-195701.56142

This paper analyzes the fine structure of alpha decay in even-even nonspherical heavy nuclei, focusing on excitation of rotational levels in the daughter nucleus. Starting from the Schrödinger equation for the daughter nucleus and emitted alpha particle, it derives a quasiclassical treatment for wea…

Determination of the Position of Substituents in Ferrocene Compounds from Infrared Absorption Spectra

A. N. Nesmeyanov, L. A. Kazitsyna, B. V. Lokshin, and I. I. Kritskaya
1957 SovietRxiv: ru-195701.56129

This study examines how infrared absorption spectra can be used to determine substituent positions in ferrocene derivatives, especially the presence of an unsubstituted cyclopentadienyl ring. Spectra of ferrocene and numerous mono- and disubstituted derivatives were compared, with particular attenti…

Electrochemical Oxidation of $\beta$-Picoline

V. G. Khomyakov, S. S. Kruglikov
1957 SovietRxiv: ru-195701.56120

This study examines the electrochemical oxidation of beta-picoline to nicotinic acid, focusing on how electrolyte composition and electrolysis conditions affect product yield. Purified beta-picoline was oxidized in sulfuric acid using primarily a lead dioxide coated lead anode in a diaphragm cell, w…

Investigation of the profiles of the coronal lines 10747 and 10798 $\mathring A$

M. G. KARIMOV and V. G. KURT
1957 SovietRxiv: ru-195701.56093

This paper reports observations of the intense coronal Fe XIII lines at 10747 and 10798 Å using a diffraction spectrograph equipped with an electron-optical converter at the coronal station of the Astrophysical Institute of the Kazakh SSR. The authors describe the instrumental arrangement, calibrati…

Mesoatoms

D. D. Ivanenko, G. E. Pustovalov
1957 SovietRxiv: ru-195701.56022

Compared with an ordinary electronic hydrogen-like atom, a mesoatom has a number of specific features: the proximity of the meson to the nucleus, the possibility of meson capture by the nucleus, the nuclear interaction of the meson with the nucleons of the nucleus, the simultaneous presence in atomi…

Secant Surfaces of Double Fibrations

Unknown
1957 SovietRxiv: ru-195701.55905

This paper studies obstruction classes for extending section surfaces in a pair of Serre fiber spaces arranged as a double fibration over a simply connected simplicial complex. Given two section surfaces over an r-skeleton that agree on the preceding skeleton, it compares the obstruction cohomology …

THE FUNCTIONAL METHOD IN QUANTUM FIELD THEORY

Yu. V. Novozhilov, A. V. Tulub
1957 SovietRxiv: ru-195701.55693

Some works on functional methods were discussed in the reviews by Berestetskii and Galanin, Spline and Feinberg. Therefore, we devote comparatively little space to the issues addressed in those articles. In Part I of the review, we consider in detail the foundations of the functional method in quant…

Dependence of $\pi^0$-meson photoproduction cross sections on nuclear mass numbers

B. B. GOVORKOV, V. I. GOLDANSKII, O. A. KARPUKHIN,
1957 SovietRxiv: ru-195701.55649

This study examines how the cross sections for photoproduction of neutral pi mesons by bremsstrahlung gamma rays depend on nuclear mass number. Experiments at the 265 MeV synchrotron compared yields from liquid hydrogen, nitrogen, oxygen, carbon, aluminum, iron, copper, cadmium, and lead, using scin…

On the Identity of Two Algebraic Fields of the $n$ -th Degree

K. K. BILEVICH
1957 SovietRxiv: ru-195701.55607

The paper addresses the problem of deciding when two algebraic fields of degree n, given by irreducible monic equations, are identical. It introduces sequences of lattice points associated with the embeddings of a field and with regions defined by bounded conjugate coordinates, and gives a computati…

On Compressions and Rarefactions of Ice in the Arctic Basin

A. I. FEL'ZENBAUM
1957 SovietRxiv: ru-195701.55605

This paper examines how atmospheric pressure fields influence compressions and dilations of sea ice in the Arctic Basin under steady and unsteady drift. Using equations for ice motion that include wind stress, water friction, Coriolis effects, and sea-surface slope, it shows that for steady drift th…

Triphenyloxonium Salts

A. N. NESMEYANOV and T. P. TOLSTAYA
1957 SovietRxiv: ru-195701.55492

This paper reports the preparation and characterization of previously unknown tertiary aromatic oxonium salts, chiefly triphenyloxonium salts, using diazo decomposition of phenyldiazonium fluoroborate in diphenyl oxide followed by anion exchange. The authors describe the fluoroborate and a series of…