Showing 50 of 25456 papers

Toward a Quantitative Consideration of the Process of Latent Photographic Image Formation by Ionizing Particles

Unknown
1957 SovietRxiv: ru-195701.27076

The paper develops a quantitative treatment of latent photographic image formation in nuclear emulsions by relating the observed track density of ionizing particles to the probability that a struck silver halide crystal becomes developable. It extends Zhdanov’s track density formula by introducing a…

Synthesis of the Alkaloid Emetamine

Unknown
1957 SovietRxiv: ru-195701.26941

This paper reports a synthesis of racemic emetamine, a minor alkaloid of ipecacuanha roots whose structure had been inferred from its relationship to emetine and from oxidative degradation studies. Using a previously developed route to emetine, the authors prepared an ester precursor, coupled it wit…

On Double Salts of Lanthanum, Cerium, Praseodymium, and Neodymium with Triphenylbenzyl Arsonium Nitrate

Unknown
1957 SovietRxiv: ru-195701.26934

This paper investigates double nitrates formed by lanthanum, trivalent cerium, praseodymium, and neodymium with triphenylbenzylarsonium nitrate, extending earlier work on related organic-base salts of rare-earth elements. The compounds were prepared by combining rare-earth nitrates with triphenylben…

On the Tautomerism of Diphenyl Phosphite

The tautomerism of dialkyl phosphites
1957 SovietRxiv: ru-195701.26870

This paper examines whether replacing alkoxy groups in dialkyl phosphites with more electrophilic phenoxy groups can shift phosphite tautomerism toward a form displaying trivalent phosphorus reactivity. Diphenyl phosphite was synthesized by hydrolysis of diphenyl chlorophosphite and characterized by…

Activity of Zinc Oxide in Lead- and Copper-Smelting Slags Subjected to Fuming

A. I. OKUNEV and V. S. BOBYKIN
1957 SovietRxiv: ru-195701.26765

This paper examines the activity of zinc oxide in lead-smelting slags during fuming, with comparison to previously studied copper-smelting slags. Using fuming-rate data, gas-phase equilibrium relations for reduction by carbon monoxide and hydrogen, and an oxygen material balance, the authors calcula…

ON THE PROBLEM OF GENERAL ANAMORPHOSIS

The basic problem of nomography still remains the clarification of the conditions under which a given equation
1957 SovietRxiv: ru-195701.26750

This paper addresses the nomographic problem of determining when an equation of the form z = F(x,y) can be represented by a Soreau determinant and thus solved by an aligned-points nomogram. Assuming sufficient differentiability and nonvanishing first partial derivatives, it derives differential cond…

On elliptic equations containing small parameters in the highest derivatives

M. I. VISHIK and L. A. LYUSTERNIK
1957 SovietRxiv: ru-195701.26634

The paper studies linear elliptic partial differential equations in which a small parameter multiplies the highest derivatives, under homogeneous first boundary-value conditions. For even-order operators satisfying positivity, ellipticity, and characteristic root assumptions, it analyzes how solutio…

Investigation of Systems of Normal Paraffin Hydrocarbons $\mathrm{C}_{30}$ – $\mathrm{C}_{34}$ and $\mathrm{C}_{30}$ – $\mathrm{C}_{36}$

Academician A. V. TOPCHIEV, N. A. NECHITAILO, L. M. ROZENBERG,
1957 SovietRxiv: ru-195701.26431

Binary systems of high molecular weight normal paraffins, triacontane with tetratriacontane and triacontane with hexatriacontane, were investigated to establish their phase behavior, which had not previously been described. Synthesized and purified hydrocarbons were examined mainly by differential t…

LUMINESCENCE OF TRIVALENT URANIUM

Unknown
1957 SovietRxiv: ru-195701.26365

This paper reports the observation of infrared luminescence from uranium-doped alkaline-earth fluoride single crystals grown under strongly reducing conditions, challenging the view that uranium luminescence is confined to hexavalent uranyl compounds. Absorption and emission spectra of CaF2, SrF2, a…

Some Data on Heterodiffusion Coefficients in $\mathrm{Cu}$ – $\mathrm{Ni}$, $\mathrm{Fe}$ – $\mathrm{Ni}$, and $\mathrm{Fe}$ – $\mathrm{Cr}$ Alloys with Distorted and Undistorted Crystal Lattices

E. F. Chaikovskii
1957 SovietRxiv: ru-195701.26326

This study determines heterodiffusion coefficients in Cu, Ni, Fe, and Cr alloy systems using an X-ray method applied to electrolytically coated metal disks and films. Specimens were prepared with distorted nonequilibrium lattices, with preliminarily annealed equilibrium components, or with mixed ini…

On Nitroperfluoroalkyl Nitrites

I. L. Knunyants and A. V. Fokin
1957 SovietRxiv: ru-195701.26072

This paper examines the chemistry of beta-nitroperfluoroalkyl nitrites, newly accessible from fluoroolefins and nitrogen oxides, with emphasis on their hydrolysis and alcoholysis. The authors show that hydrolysis gives unusually stable alpha-nitroperfluorocarboxylic acids rather than the behavior ty…

On the Nature of Catalytic Hydrogen Currents in Polarography

Unknown
1957 SovietRxiv: ru-195701.25744

This paper examines the mechanism of catalytic hydrogen waves in polarography, focusing on cases produced by organic bases such as pyridine. It argues that these currents are not caused by a lowering of the activation energy for hydrogen ion discharge, but by a reversible discharge of the protonated…

Two Methods for the Technical Synthesis of Methylpentadiene

M. I. FARBEROV, K. A. MACHITINA, and S. I. KRYUKOV
1957 SovietRxiv: ru-195701.25681

This paper presents two technical routes for synthesizing methylpentadiene, a diene of interest for polymer and copolymer production but previously of limited industrial accessibility. The first method involves catalytic cleavage of 2,4,4,6-tetramethyldioxane-1,3 with steam at 300 to 325°C, giving a…

Theoretical Model of a Cumulus Cloud

Unknown
1957 SovietRxiv: ru-195701.25454

This paper develops a theoretical, plane, stationary model of ordered thermal convection in an atmosphere without general air motion, intended to describe conditions under which cumulus cloud formation may occur. Starting from simplified thermohydrodynamic equations with small temperature and pressu…

Embedding Theorems for Abstract Set Functions

S. L. SOBOLEV
1957 SovietRxiv: ru-195701.25375

This note extends Sobolev embedding theorems to abstract functions of sets in the space Ψp, defined as the closure of step measurable functions and characterized by absolute continuity and continuity under shifts. It defines integrals of such set functions against Lp′ kernels, proves continuity resu…

Synthesis and Properties of Mono-, Di-, and Tri-$n$-tolylalkylsilanes

N. S. NAMETKIN, Academician A. V. TOPCHIEV, GU CHAN-LI, and N. A. LEONOVA
1957 SovietRxiv: ru-195701.25289

This study addresses the limited knowledge of organosilicon hydrocarbons containing p-tolyl groups, particularly alkyl-substituted mono-, di-, and tri-p-tolylsilanes and related ethoxy derivatives. The authors synthesize these compounds through reactions of p-tolyl organolithium or Grignard reagents…

Tautomerism of arylazotropolones

Corresponding Member of the Academy of Sciences of the USSR M. M. Shemyakin, F. A. Mendelevich,
1957 SovietRxiv: ru-195701.25249

This communication investigates the tautomerism of 5-arylazotropolones, whose observed reactivity was found to be inconsistent with a simple arylazotropolone structure. A series of compounds prepared by azo coupling of substituted tropolones with diazonium salts was examined through reactions with o…

New Data on the Relationship Between the Structure of Polysaccharides (Cellulose) and the Direction of Chemical Reactions Occurring During Their Thermal Decomposition

O. P. GOLOVA, A. M. PAKHOMOV, and E. A. ANDRIEVSKAYA
1957 SovietRxiv: ru-195701.25098

This study examines how the physical structure of cellulose, especially macromolecular packing density, influences the direction of chemical reactions during thermal decomposition in vacuum. Cellulose preparations of similar chemical composition but different structural states were produced by disso…

On the numerical solution of a boundary value problem for a system of ordinary differential equations

Let the problem be given
1957 SovietRxiv: ru-195701.24171

This paper studies a finite difference approximation for a boundary value eigenvalue problem involving a system of ordinary differential equations with piecewise discontinuous coefficients and matching conditions at interior points. Under symmetry, positivity, smoothness, and equal mesh size assumpt…

ON FILTRATION IN A RECTANGULAR COFFERDAM WITH A VERY LARGE HEIGHT OF CAPILLARY RISE

![Fig. 1 and Fig. 2](image)
1957 SovietRxiv: ru-195701.24002

This paper analyzes steady filtration through a very high rectangular cofferdam when the capillary rise is also taken to be very large and the capillary zone is fully saturated. Using a complex potential formulation, conformal mapping, and Christoffel-Schwarz transformations, it derives integral rel…

Embedding Theorems for a Space with a Metric Degenerating at a Finite Number of Interior Points of a Bounded Domain

Unknown
1957 SovietRxiv: ru-195701.23980

This paper proves embedding results for function spaces on a bounded plane domain whose metric degenerates at an interior point. It defines completions of smooth functions vanishing near the boundary and the singular point under weighted quadratic forms involving first, and then second, generalized …

ON THE MECHANISM OF ACTION OF REAGENTS IN FLOTATION

![Fig. 1. Trace of a drop of an aqueous solution of xanthate on the surface of a galena grain](image)
1957 SovietRxiv: ru-195701.23591

This paper examines the role of the three-phase contact line in the action of collector reagents during froth flotation, addressing earlier hypotheses that reagent molecules concentrate preferentially at the mineral, water, and air boundary. Using potassium ethyl xanthate labeled with radioactive su…

ON ALKYL ESTERS OF ETHYLTHIOARSINOUS ACID

Unknown
1957 SovietRxiv: ru-195701.23260

This paper describes the preparation and properties of alkyl esters of ethylthioarsinous acid of the general formula C2H5As(SR)2, a class of compounds previously little studied. The authors synthesize several ethyl, propyl, butyl, isoamyl, and hexyl derivatives by reactions of ethyldichloroarsine wi…

ASYMPTOTIC BEHAVIOR OF SOLUTIONS OF A NONLINEAR BOUNDARY-VALUE PROBLEM IN BOUNDARY-LAYER THEORY

In boundary-layer theory the following boundary-value problem is well known:
1957 SovietRxiv: ru-195701.23244

This note studies the large argument behavior of solutions to a nonlinear third order boundary value problem arising in boundary layer theory, with parameters beta at least zero and positive limiting slope k. The authors transform the problem by using the dependent variable as the independent variab…

Tungsten–boron phases

Unknown
1957 SovietRxiv: ru-195701.23213

This study refines the phase relations in the tungsten, boron system using hot-pressed and annealed alloys examined by chemical, microhardness, metallographic, and X-ray methods. Alloys with nominal compositions from very low boron content to boron-rich preparations were analyzed to identify phase f…

Intercrystalline interlayers in gypsum

V. A. Zolotov
1957 SovietRxiv: ru-195701.23182

This paper investigates the nature and properties of intercrystallite boundaries in natural polycrystalline gypsum dihydrate, a nonmetallic material relevant to building practice. Using polarizing microscopy of thin sections, acid etching, dye adsorption, in situ heating, fracture observation, and c…

ON A FAMILY OF CLASSES OF FUNCTIONS OF THE ALGEBRA OF LOGIC AND THEIR REALIZATION IN THE CLASS OF $\Pi$-CIRCUITS

Unknown
1957 SovietRxiv: ru-195701.23026

This paper studies the realization of Boolean functions by parallel series contact circuits, focusing on the classes of functions of n variables that take the value 1 on exactly k input sets. It presents a synthesis method based on grouping identical columns in the matrix of the satisfying assignmen…

Sequence of Hydrogenation of the Double Bonds of Cyclopentadiene on Pd and Pt Blacks

L. Kh. Freidlin and B. D. Polkovnikov
1957 SovietRxiv: ru-195701.22796

This study examines the liquid-phase hydrogenation of cyclopentadiene on palladium and platinum black catalysts at 25 °C and atmospheric pressure, using cyclohexane or ethanol as solvent. By following hydrogen uptake kinetics and testing for residual cyclopentadiene, the authors compare the sequence…