SovietRxiv · Open Access in English
Rediscovering the Soviet scientific archive, in English
25357 full-text translations 14926 English PDFs 22539 abstracts
Showing 50 of 4600 papers in Chemistry
This paper develops a theoretical treatment of the cathodic growth of filamentary silver crystals in electrolytes containing surface-active impurities. Starting from impurity effects on two-dimensional nucleation, diffusion of metal ions and impurity molecules, adsorption, and overvoltage relations,…
This paper examines the syn and anti isomerism of 3-arylhydrazones of 6-methylpiperidinedione-2,3, compounds encountered in work on biologically active tryptamine derivatives. The authors prepared a series of arylhydrazones by the Japp-Klingemann reaction and compared paired yellow benzene-soluble a…
This paper analyzes the possibility of obtaining population inversion, described as a negative temperature, in solutions undergoing fast reversible photochemical reactions whose equilibria differ strongly in the ground and electronically excited states. Using a four-level scheme, it derives conditio…
This study investigates crystalline phases in the barium oxide, germanium dioxide system as analogues relevant to silicate chemistry and cement materials. Using solid state synthesis of multiple BaO to GeO2 compositions, combined with chemical analysis, X-ray diffraction at ordinary and elevated tem…
This paper examines the selectivity and stereospecificity of hydrogenation of mono- and disubstituted acetylenic hydrocarbons on nickel, cobalt, palladium, platinum, and rhodium catalysts. Using kinetic measurements and gas-liquid chromatographic analysis of hydrogenation products, the authors disti…
This paper investigates anomalous combustion behavior of ammonium perchlorate, especially the decrease in burning rate and onset of pulsating or extinguishing combustion at elevated pressures. Using thin tungsten-rhenium thermocouples, the authors measured temperature profiles in pressed specimens b…
This study investigates the microwave rotational spectrum of the halogen-substituted ethane molecule F2HC-CDHF, with attention to hindered internal rotation and the possible isomeric states produced by rotation about the carbon-carbon bond. Using a gas radiospectroscope with electric molecular modul…
This paper develops a thermodynamic model relating the structure of the surface layer of a pure liquid to surface tension, its temperature coefficient, molecular orientation, association, and layer thickness. Starting from the force balance for a stretched liquid film and using Frenkel’s expression …
Infrared absorption spectra were measured for carbyne and a series of polyynes obtained by oxidative polycondensation of acetylene derivatives, including phenylacetylene, para-diethynylbenzene, and para-nitrophenylacetylene. The spectra are interpreted in terms of terminal and disubstituted acetylen…
This study examines the composition and structure of cobalt(II) halide complexes formed in anhydrous ethanol at very high chloride and bromide ion concentrations. Absorption spectra of CoCl2 and CoBr2 solutions containing varying amounts of LiCl or LiBr were measured with an SF-10 spectrophotometer …
This study extends kinetic measurements of C5 dehydrocyclization on platinized carbon to 3-ethylpentane, isobutylbenzene, and sec-butylbenzene, comparing paraffinic and alkylbenzene substrates that form single cyclization products. Product yields as functions of contact time and temperature indicate…
This study examines how aggregation state and electron-acceptor additives affect the optical absorption and photoelectric response of thin magnesium phthalocyanine layers. Vacuum-sublimed, solvent-treated, annealed, and solution-deposited films were characterized by absorption spectroscopy, microsco…
This study examines why concentrated emulsions and polymer latices can show high aggregative stability even when measured adsorption layers of surfactants appear weak. Using measurements of limiting shear stress at water, xylene interfaces for OP-10, Nekal NB, and Pluronic surfactants, together with…
This study examines the formation and rapid gas-phase transport of fission-product zirconium-97 as volatile zirconium tetrachloride during the slowing down of fission fragments in chlorine-containing and related gas mixtures. Using a flow fluoroplastic ampoule with an enriched uranium oxide target, …
This paper reports ligand exchange reactions of ferrocene, previously considered resistant to replacement of its cyclopentadienyl rings. Heating ferrocene or substituted ferrocene with aromatic hydrocarbons in the presence of aluminum chloride, often with aluminum powder as a reducing agent, replace…
This study investigates the mechanism of the polymorphic transition in p-dichlorobenzene between the low-temperature monoclinic alpha phase and the high-temperature triclinic beta phase. Using optical microscopy with controlled heating and X-ray Laue photography of the same crystals before and after…
This study examines heterogeneous crystallization in lithium aluminosilicate photosensitive glass, focusing on how precrystallization treatment controls silver crystallization centers and the resulting microstructure. Glass samples were ultraviolet irradiated, subjected to slow heating or single and…
This study examines chemical polarization and activation barriers in high-temperature oxide melts, focusing on the reduction of FeO in aluminosilicate slag by carbon dissolved in liquid iron. The authors combine kinetic measurements using electrocapillary motion of metal droplets with anodic polariz…
This paper investigates the reaction of phosgene with acylmethylene and vinylene homolog derivatives of N-substituted heterocyclic bases, including benzthiazoline, thiazoline, benzselenazoline, indoline, and dihydroquinoline systems. The authors show that phosgene converts these compounds in high yi…
Electron paramagnetic resonance was used to study bis-dimethylglyoximato-copper(II) in crystalline form and in water, methanol, and dioxane solutions, with attention to the Cu, N bonding and hyperfine structure. The crystalline compound shows an S = 1/2 spectrum with no evidence of exchange pairing …
This study examines the formation and properties of solid solutions between tricalcium silicate, a principal cement mineral, and yttrium oxyorthosilicate, motivated by possible crystal-chemical similarity and calcium-yttrium isomorphism. Mixtures containing varying amounts of yttrium oxyorthosilicat…
This paper generalizes experimental viscosity data for saturated paraffin hydrocarbons from methane through n-octane over broad temperature and pressure, or density, ranges. Using a corresponding-states formulation, the authors reduce viscosity increments relative to atmospheric-pressure values by t…
This study examines the solid-state thermal substitution of ammonia by nitrite ions in optically active cis-diamminobis(ethylenediamine)cobalt(III) nitrite as a means of probing the reaction mechanism. Heating the active nitrite at 105 to 110 degrees for 12 hours gave inactive cis-dinitrobis(ethylen…
This study examines the orientation of addition reactions of representative electrophilic and nucleophilic reagents to the unsymmetrical conjugated diyne ethyldiacetylene, or hexadiyne-1,3. Bromine, hydrogen bromide, sodium methylate, and sodium ethyl mercaptide were tested, and the products were ch…
This study examines whether heterogeneous catalysts known to promote gas-phase hydrocarbon oxidation can increase the selectivity of liquid-phase isobutylene oxidation. Liquefied isobutylene was oxidized with air at 140 degrees and 50 atm in a stirred autoclave in the presence of several metal oxide…
The study examines intraparticle diffusion of several organic cations in KU-2 sulfonic cation exchangers with divinylbenzene contents from 2 to 20 percent. Sorption rates were measured under static conditions during the initial exchange period at different temperatures, and diffusion coefficients, a…
This study examines the cathodic reduction of oxygen on smooth platinum in alkaline solution using a rotating disk electrode with a ring electrode to clarify whether hydrogen peroxide is formed as an intermediate. Polarization measurements in 0.125 N potassium hydroxide, supported by ring detection …
This study examines whether phenyl radicals generated from benzoyl peroxide in benzene undergo intramolecular isomerization before forming diphenyl. Benzoyl peroxide labeled with carbon 14 at the ring carbon bonded to the carboxyl group was used in both thermal reactions and photodecomposition, and …
This paper examines elementary stages in the heterogeneous recombination of hydrogen atoms on an aluminum surface, with particular attention to chemisorption heat, desorption, and the influence of gas pressure and catalyst temperature. Using experimental recombination data and graphical calculations…
This paper examines whether transition metal compounds with suitable electronic configurations can display carbenoid reactivity, using in situ generated titanocene and diphenylacetylene as a test case. Reaction of titanium tetrachloride with sodium cyclopentadienide in the presence of tolane gave a …
This study examines homomolecular oxygen isotope exchange on ZnO and NiO at room temperature, comparing behavior with the more commonly studied high-temperature region. Using prepared oxide samples conditioned in vacuum and exposed to oxygen isotope mixtures, the authors measured exchange kinetics a…
This study examines how different adsorbed forms of oxygen on titanium dioxide affect its photoactivity toward hydrogen photosorption. Using manometric measurements together with electrical conductivity monitoring over 90 to 600 K, the work identifies sequential irreversible transformations of adsor…
This study examines the bonding heterogeneity of oxygen adsorbed on platinum films through isotopic exchange between gaseous and adsorbed oxygen, together with homomolecular oxygen isotope exchange. Platinum films were prepared in vacuum, treated with oxygen under different temperature conditions, a…
The paper examines the anomalously rapid decomposition of benzoyl peroxide during polymerization of phenylacetylene and related acetylenic hydrocarbons. Using kinetic measurements in phenylacetylene, deuterated phenylacetylene, methylphenylacetylene, and inhibited systems, the authors compare peroxi…
This study investigates the coextraction of calcium and strontium from weakly alkaline aqueous media with 8-hydroxyquinoline complexes of scandium, neodymium, thorium, and aluminum in benzene. Using radioactive tracers, pH-controlled extraction experiments, back-extraction, spectrophotometry, electr…
This study examines phototransformations of free radicals formed in gamma irradiated polypropylene, using electron paramagnetic resonance spectra measured after irradiation, illumination, and controlled heating. The authors show that short wavelength ultraviolet light at 77 K converts allyl radicals…
This study examines how iodine alters the electrical properties of radiation-thermally modified polyethylene, whose conductivity, activation energy, and thermoelectric power depend on heat-treatment temperature and spatial polyconjugation. Conductivity and thermoelectric power were measured for samp…
This paper develops a theoretical treatment of the kinetics of electrochemical oxidation and reduction reactions at semiconductor electrodes, extending earlier work on metal electrodes to account for a forbidden band and low carrier concentrations. Using a solvent reorganization model of electron tr…
The study examines extraction equilibria in the quinary system uranyl nitrate, nitric acid, water, carbon tetrachloride, and a 27.6 wt.% solution of the monobutyl ester of dibutylphosphinic acid in the stratification region at 25 degrees C. Using physicochemical analysis, extraction rays, and determ…
This paper examines whether potential energy coefficients used in molecular vibrational spectra can be transferred between polyatomic molecules containing an identical structural group. By comparing force constant matrices with compliance, or influence, coefficient matrices and analyzing their physi…
This study examines the reactions of methyl esters of ferrocene mono- and dicarboxylic acids with Grignard reagents derived from trimethylchloromethylsilane and trimethyl-gamma-chloropropylsilane. The trimethylsilylmethyl reagent, a structural analogue of neopentylmagnesium chloride, reacted anomalo…
This study examines how substituents affect the infrared absorption bands characteristic of cyclopentadienyl rings in ferrocene derivatives, focusing on C,H stretching near 3100 cm-1 and ring stretching near 1100 cm-1. Frequencies and integral intensities were measured in carbon tetrachloride soluti…
This paper proposes a spectroscopic method for estimating the energy of formation of intramolecular hydrogen bonds that generate quasiaromatic six-membered rings in conjugated systems. Using shifts of the O-H stretching vibration in infrared spectra and a calibration constant derived from carboxylic…
This paper examines the critical condition for thermal self-ignition of reacting systems when heat is removed simultaneously by internal conduction and surface convection. Starting from the nonstationary heat equation with an Arrhenius reaction rate, the authors linearize the problem in the high act…
A mass spectrometric method is proposed for determining partial vapor pressures and relative molecular ionization cross sections in multicomponent systems from isotherms of complete evaporation. The method relates ion-current integrals to the amounts evaporated by the Knudsen effusion equation, prov…
This study examines how low molecular weight substances with differing compatibility affect the mechanical behavior and glass transition of rigid chain cellulose esters, focusing on whether plasticization can occur through changes in supramolecular structure rather than only through molecular mixing…
This study examines photochemical processes in binary solutions of magnesium phthalocyanine and uranyl nitrate hexahydrate in pyridine, acetone, and ethanol under selective irradiation. The authors distinguish an irreversible reaction, attributed to formation of a uranyl phthalocyanine-like complex …
The paper reports the structural elucidation of ungerine, an alkaloid isolated from Ungernia severtzovii, and assigns it to the homolycorine type. Evidence is drawn from elemental composition, infrared and ultraviolet spectra, alkaline opening and acid reclosure of a lactone, reductions to tetrahydr…
This paper proposes an additive method for estimating activation energies of radical substitution reactions of the form R radical plus R'X, based on treating the activated complex as a sum of bond-energy contributions. The author derives an expression in which the activation energy equals the dissoc…
