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 study reports an observed effect of gamma irradiation on the phase composition of lithium aluminosilicate glass-ceramics. Transparent glass-ceramic samples containing beta-eucryptite were irradiated with Co-60 gamma rays at doses from 10^2 to 10^5 r, and their phase changes were examined by X-r…
This study examines the relative stability of the N-glycosidic bond in p-carboxyphenyl glycosylamines containing D-glucose, D-galactose, D-xylose, and L-arabinose residues. To avoid uncertainties associated with polarimetric measurements and possible tautomerism, the authors developed a colorimetric…
This study examines the liquid phase oxidation of low concentrations of carbon monoxide using acidic palladium and copper salt solutions, motivated by analogies with platinum group catalyzed olefin oxidation. Experiments in a flow reactor at 20 to 60°C varied carbon monoxide concentration, gas flow,…
This paper describes the synthesis of symmetrical and unsymmetrical alpha,alpha-prime-difluoro-alpha,alpha-prime-dialkylethylenes using aliphatic and aromatic organolithium compounds with tetrafluoroethylene or trifluoroolefin precursors. The authors examine how reaction temperature and the structur…
This paper examines thermodiffusion fractionation of polymer solutions, focusing on polyisobutylene in heptane and on the limitations imposed by high molecular weight. Using a vertical thermodiffusion column, the authors compare concentration and intrinsic-viscosity changes over time and relate them…
Pentafluorophenylmagnesium chloride was prepared from pentafluorochlorobenzene by an entrainment reaction with ethylene bromide in ether, providing a more accessible route to pentafluorophenyl derivatives than routes based on bromo or iodo precursors. Its reactions with water, carbon dioxide, iodine…
The paper investigates the catalytic activity of exceptionally clean platinum surfaces in the oxidation of hydrogen, addressing conflicting earlier interpretations that attributed activity either to clean platinum or to gas-activated and contaminated surfaces. Using ultrahigh-vacuum preparation, cle…
This paper examines the use of electron microscopy and X-ray phase analysis for studying glass-crystalline materials, with emphasis on controlling glass crystallization in sitall production. Using carbon and platinum-carbon replicas of etched fracture surfaces together with powder X-ray diffraction,…
This study examines how substituent electronic effects are transmitted through azomethine-containing bridges in aromatic Schiff bases and related quaternized compounds. Acid ionization constants were measured potentiometrically for several substituted phenolic series, and the results were correlated…
The paper investigates the addition of nitrosyl chloride to three simple vinyl ethers, methylisopropenyl, methylpropenyl, and methyl-alpha-phenylvinyl ethers, in order to assess the effect of electron-donating methoxy substitution on reactivity and product formation. Low-temperature reactions in eth…
This paper reports a preparative synthesis of previously unknown 5,5-dialkyl-substituted delta-2-pyrazolines by condensation of tertiary acetylenic chlorides with anhydrous hydrazine. The reaction affords liquid nitrogenous products of composition CnH2nN2 in moderate yields, and their structures are…
This paper addresses the synthesis of alpha,beta-unsaturated ketones containing cyclopropyl groups, compounds not readily accessible by Kondakov-type methods because Lewis acids can isomerize the cyclopropane ring. The authors develop a route based on the reaction of isocrotyllithium, generated from…
This paper examines the extraction of uranyl nitrate by pyridine N-oxide derivatives, focusing on how substituent structure affects solvate formation and solubility in organic solvents. Spectroscopic, solubility, direct synthesis, and distribution isotherm data indicate that alpha-alkylpyridine N-ox…
This paper examines the mutual influence of atomic groups in molecules where a pi-bond system and a substituent containing a heavy atom are separated by a single-atom bridge, especially methylene, rather than directly conjugated. Using ultraviolet absorption spectra, with supporting references to vi…
This study examines whether anodic peaks in amalgam polarography of nickel arise from oxidation of surface nickel or nickel dissolved in mercury, and applies this distinction to determine nickel solubility and diffusion in mercury. A modified accumulation procedure was used in which nickel was pre-e…
This study examines the catalytic vapor phase isomerization of esters of beta-tetrahydrofurylpropionic acid and its alpha-methyl and alpha-ethyl homologs as a route to esters of gamma-ketoenanthic acids. The reactions were carried out over platinized carbon at 250 to 300 degrees, with products isola…
This paper examines the relationship between the acidity of ammine complexes and infrared frequencies of symmetric deformation vibrations of coordinated ammonia. Using reported and newly measured spectral data, mainly for platinum ammine complexes, the authors compare pKa values with the frequency s…
This paper examines Friedel-Crafts alkylation of ferrocene, addressing the competing oxidation of ferrocene and its homologs to ferricinium salts that lowers product yields. The authors study alkylation with ethyl bromide and tert-butyl chloride in the presence of an equimolar aluminum chloride and …
This paper examines how the structure of bisphenol diol components influences the properties of synthesized polyarylates, with particular attention to substituents at the central carbon atom. Polyarylates prepared by equilibrium and interfacial polycondensation are grouped into three structural type…
This study examines whether ribbon-like supramolecular structures previously observed in thin rubber films also occur in bulk rubbers and persist during vulcanization. Using electron microscopy with lacquer-carbon and carbon replica methods on fractured or torn surfaces, the authors investigated iso…
This study examines how formation of intermolecular N-H...O=C hydrogen bonds affects the infrared absorption intensities of C=O and N-H stretching bands in four N-monosubstituted amides. Spectra of carbon tetrachloride solutions over a wide concentration range were used to compare associated and non…
This study examines the thermochemistry of uranyl nitrate extraction from aqueous solution by tributyl phosphate, focusing on the heat effect associated with formation of the uranyl nitrate tributyl phosphate solvate. Direct calorimetric measurements were used to determine the heat of extraction, th…
This paper examines primary radical formation during radiolysis of solid organic substances containing polar substituents, especially compounds of the type RX, where conventional homolytic bond rupture appears inconsistent with the Franck-Rabinowitch cage effect. It proposes heterolytic decompositio…
Decafluorodiphenyl was prepared from pentafluorochlorobenzene by a high-temperature Ullmann reaction and used to examine nucleophilic substitution in this highly fluorinated biphenyl system. Reactions with ammonia, hydrazine, dimethylamine, hydroxide, and methoxide gave the corresponding 4,4′-disubs…
This study examines how solid additives influence the mechanism and rate of gamma radiation polymerization of isobutylene and styrene, separately and jointly, in bulk at low temperatures. Using dilatometric and ampoule experiments with zinc oxide and finely dispersed glass powder, the authors compar…
This study examines the role of counterion sorption in the coagulation of negatively charged arsenic and antimony sulfide hydrosols by mixtures of electrolytes showing antagonistic, additive, or synergistic coagulating action. Using radiometrically labeled rubidium, calcium, strontium, and yttrium s…
This study examines the Mössbauer effect in a range of tin compounds, with emphasis on complexes in which tin has coordination number six. By comparing chemical shifts, quadrupole splitting, and relative probabilities of recoil-free resonant gamma fluorescence at 78 K and 300 K, the authors argue th…
This study examines how solvent-dependent supramolecular structure affects the mechanical properties and gel formation of amorphous isotactic polystyrene. Films prepared from chloroform and decalin solutions were tested mechanically at 20 and 120 degrees and examined by polarizing and electron micro…
This study examines the acid-catalyzed denitrosation of para-substituted phenyl-N-methylnitrosamines in sulfuric acid, a reaction relevant to diazotization chemistry and the Fischer-Hepp rearrangement. Using spectrophotometric kinetic measurements at 25 °C in the presence of urea, the authors relate…
This paper proposes and experimentally examines a variant of elution gas chromatography in which the sorbent moves through the column, either in the same direction as the carrier gas or in the opposite direction. The authors derive expressions for retention time, band width, and a separation criteri…
This study examines the mechanism of radical formation during photoirradiation of frozen ethanol solutions of triphenylamine at 77 K, with emphasis on the role of hydrogen bonding. Electron paramagnetic resonance spectra were measured for ethanol, deuterated ethanols, and ethanol isopentane mixtures…
The paper examines the mechanism by which dimethylcyclosilazanes undergo acid induced rearrangements involving both ring expansion and, under some conditions, ring contraction. Because intermediates in the rearrangement could not be isolated directly, the authors used model reactions of trimethylchl…
This study examines hydrosilylation reactions for systems previously lacking reported data: addition of methyl- and ethyldichlorosilanes to vinyl-substituted organocyclotetrasiloxanes, and addition of isoprene to a hydrogen-containing organocyclotetrasiloxane. Using chloroplatinic acid catalysis, th…
The study examines the gamma radiolysis and ultraviolet photolysis of selected Co(III) complexes, chiefly aquopentaammine and diaquotetrammine cobalt chlorides, with comparison to potassium trioxalatocobaltate(III). Changes in irradiated aqueous solutions were followed by absorption spectroscopy, pH…
This study examines the direct low-temperature synthesis of potassium zeolites from alkaline silica-alumina gels in the K2O, Al2O3, SiO2, H2O system, focusing on gel compositions with 70 to 95% water and crystallization at 90°C. Four potassium zeolite types were obtained, potassium chabazite, potass…
This paper addresses the synthetic preparation of neutral plasmalogens, aldehydogenic glycerolipids whose biological role and biosynthetic relationships were incompletely understood. The authors develop a route based on reversible transformations between long-chain aldehyde acetals and 1-alkenyl eth…
This study examines the behavior of zinc and cadmium tellurides in the liquid state, focusing on chemical interaction between the components in Zn, Te and Cd, Te melts. High-purity alloys of varied composition were prepared and analyzed by physicochemical methods using viscosity and electrical condu…
This paper describes the synthesis and characterization of several ferrocenylamine derivatives and examines oxidative transformations of ferrocenylamines. Diphenylferrocenylamine and monophenylferrocenylamine are prepared from bromoferrocene using sodium derivatives of diphenylamine or acetanilide i…
This study examines the thermal decomposition rates of ten unsaturated organosilicon peroxides containing one, two, or three peroxide groups at silicon. Decomposition was measured iodometrically in sealed nitrogen-filled ampoules at 120, 130, and 140 degrees Celsius in aromatic solvents, and rate co…
This paper investigates the possibility of fixing molecular nitrogen under mild conditions using complex catalysts formed from transition metal salts and organometallic or hydride reagents. Guided by the hypothesis that nitrogen can be activated through formation of a metal pi-complex, the authors t…
This study examines how supersaturation affects the activity of growth centers on the tetrahedral face of sodium bromate crystals, addressing theoretical predictions from dislocation-based crystal growth theory. Crystal growth was observed microscopically under steady conditions at 40°C, with repeat…
This paper extends Pople’s molecular orbital treatment of diamagnetism to cyclic molecules and applies the resulting expressions to the magnetic anisotropy of cyclopropane. Using a one-electron LCAO approximation in a magnetic field, the author derives interatomic diamagnetic and paramagnetic suscep…
This study examines how substituents affect fluorine-19 NMR chemical shifts and fluorine-phosphorus spin-spin coupling constants in fluorophosphates, fluorophosphonates, and related fluoroanhydrides. High-resolution NMR measurements are used to derive additive substituent increments for both shieldi…
This paper applies an empirical nuclear quadrupole resonance method to determine structural fragments in chlorine-containing chain polymers by calculating Cl35 resonance frequencies from substituent effects transmitted along carbon chains. The authors compare calculated and pulsed NQR measurements f…
This paper reports reactions that replace bromine in bromoferrocene with aromatic and heterocyclic radicals using copper-containing reagents. Tetraphenylborocuprate pyridinate, or mixtures of organoborate salts with cuprous bromide, arylate bromoferrocene to give phenylferrocene and p-tolylferrocene…
This paper reviews and revises proposed mechanisms for carbon combustion and gasification, focusing on the role of intermediate carbon oxygen complexes and the differing behavior of dry and moist reaction media. It argues that earlier schemes inadequately separate heterogeneous surface reactions fro…
This paper investigates the experimentally elusive nonstationary burning rate of smokeless propellant predicted by combustion theory for rapid changes in pressure and heat flux at the burning surface. The authors develop a semi-closed chamber method in which propellant first burns near atmospheric p…
The paper reports experimental determinations of sodium carbonate solubility in water from 200 to 500°C under pressures up to about 1500 to 2400 kg/cm², including conditions above the critical temperature of water. Solubility was measured using pressure concentration curves in an autoclave and check…
This study investigates crystallization overvoltage during galvanostatic electrodeposition of silver and copper from molten nitrate and chloride salts onto platinum or tungsten cathodes. By recording cathode potential transients immediately after current pulses, the authors observed maxima in overvo…
The study examines formation of semiconducting polymeric tetracyanoethylene complex films on copper and nickel by measuring changes in Volta potential and electron work function during adsorption, desorption, and film growth. Using a vibrating capacitor method with hydrogen-reduced metal electrodes …
