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
The study examines the temperature dependence of sodium borohydride solubility in pyridine, a solvent compatible with the borohydride anion but previously characterized only at two temperatures. Using visual polythermal and isothermal methods with analytical determination of liquid and solid phases,…
The paper develops a treatment of volume kinetic waves in polarography for unbuffered solutions containing exactly neutralized salts of weak acids, where the electroactive species is formed by protonation of acid anions by water near the electrode. Using the Koutecký-Weber and reaction-layer approac…
This study examines how conformational factors influence the cyclization of linear depsipeptides, using eight stereoisomeric tetradepsipeptides composed of alternating N-methylvaline and alpha-hydroxyisovaleric acid residues. The authors synthesize these compounds, cyclize them under standard high-d…
This study examines the photoreduction of tetraphenylporphin in deoxygenated pyridine using hydrazine or hydrogen sulfide as reducing agents, with absorption spectra measured in the visible and infrared regions. Irradiation produced distinct green and pink photoreduced forms, whose interconversion, …
This study examines liquid phase hydrogenation of allyl alcohol, eugenol, acrolein, and heptene-3 in ethanol on platinum black and Pd/BaSO4 under uniform continuous feed of the unsaturated compound. The authors combine kinetic measurements with simultaneous catalyst potential measurements at 5 and 3…
This paper examines the indirect generation of ferrocenediazonium species from diazoamino derivatives of ferrocene, since direct diazotization of ferrocenylamine is destructive to the ferrocene nucleus. Acidolysis of diazoaminoferrocene and benzenediazoaminoferrocene at low temperature gives violet …
This study examines the effects of gamma and ultraviolet irradiation on aqueous solutions of cobalt(III) tris(ethylenediamine) chloride and nitrate at several concentrations, doses, acidities, and gas saturation conditions. Changes were followed by absorption spectroscopy in the ultraviolet and visi…
Mössbauer spectra of a series of polymeric organotin oxides, R2SnO, were measured at liquid nitrogen temperature and compared with spectra of related organotin carboxylates, bis-alkyl-substituted tin oxides, and distannane derivatives. The observed chemical shifts and quadrupole splittings differ ma…
This study examines how secondary molecular ordering in crystallizing polymer melts affects viscoelastic behavior under high pressure, with emphasis on processes governed by chain mobility such as autohesion and crystallization. Polytetrafluoroethylene powders and granules were pressed at elevated t…
This paper proposes a spectroscopic method for determining the anisotropy and absolute polarization of electronic transitions in polar molecules without inducing optical anisotropy or performing polarization measurements. The approach relates solvent-dependent shifts in absorption and fluorescence s…
This paper develops a statistical vibrational treatment of intramolecular rearrangements, broadly defined as transformations of an isolated molecule into another molecule, isomer, conformation, or fragments. Assuming harmonic intramolecular vibrations in thermal equilibrium, it derives probability d…
The study examines the extraction system Th(NO3)4, HNO3, H2O, and tributyl phosphate at 25 °C using the method of extraction rays. Equilibrium aqueous and organic phase compositions, densities, solubility behavior, and distribution coefficients for thorium nitrate and nitric acid were measured acros…
This study examines the mechanism of ultraviolet photodehydrogenation of alcohols by aromatic amines at 77 K, using electron paramagnetic resonance to detect radicals formed in frozen methanol and ethanol solutions. Experiments with benzene and silica gel show evidence for hydrogen atoms abstracted …
This paper examines whether the reaction previously observed between methacrylic acid derivatives and unsymmetrical dimethylhydrazine is general for anhydrides and acid chlorides of alpha,beta-unsaturated aliphatic acids. Reactions of acrylic and crotonic acid chlorides and crotonic anhydride with d…
The article addresses the difficulty of potentiometric measurements in poorly conducting or nonconducting media, especially during catalytic hydrogenation studies where conventional reference electrode arrangements require unstable electrolyte films or additives. It describes an electrode device con…
This paper develops a kinetic approach to defining an alkalinity function for concentrated aqueous alkali solutions, where indicator methods are unsuitable. Using the alkaline hydrolysis of delta-valerolactam, the authors measured effective rate constants in LiOH, NaOH, and CsOH over specified conce…
This paper develops an approximate method for estimating single-stage isotope separation factors in chemical exchange reactions when full statistical calculations from spectroscopic data are impractical. Starting from the statistical thermodynamic expression for a simple exchange reaction, the autho…
This paper investigates whether radicals in solution can undergo rearrangement with migration of an arylthio group, using acetone diphenylmercaptal as a substrate. Treatment of the mercaptal with tert-butyl peroxide in refluxing chlorobenzene produced 1,2-diphenylthiopropane, along with phenylisopro…
This study examines how the intensity of spectral lines of trace elements in silicate matrices depends on the phase diagrams of binary oxide systems. Standards in the SiO2-Al2O3, SiO2-MgO, and Al2O3-MgO systems were prepared with added copper, silver, cobalt, and nickel, then evaporated from a carbo…
This study examines how electron donor additives affect the microstructure of polybutadiene formed by stereospecific polymerization of butadiene with a titanium tetraiodide and triisobutylaluminum catalytic system. Using dibutyl sulfide and triethylamine in benzene solution at 30°C, the authors comp…
The paper examines the mechanism and kinetic stages of ethylene oxidation by palladium chloride in aqueous chloride solutions, with particular attention to the roles of chloride concentration, acidity, solvent isotope effects, and possible hydroxide participation. Kinetic measurements show first-ord…
Rhenium dichloromonoacetate was prepared in crystalline form from reduced perrhenate solutions treated with glacial acetic acid and acetone, and its composition, oxidation state, water content, magnetic behavior, molecular weight, and thermal properties were examined. Analytical data, cryoscopic mol…
This study investigates the chemical nature of oxygen chemisorbed on partially reduced titanium dioxide using electron paramagnetic resonance. Anatase samples reduced by vacuum heating were exposed to oxygen at room temperature, and pressure dependent EPR spectra were compared with adsorption measur…
This study examines primary photoreduction processes in tetrapyrrole pigments under powerful pulsed illumination, aiming to distinguish hydrogen atom transfer from intermolecular electron transfer. Using time-resolved absorption measurements on magnesium phthalocyanine and hematoporphyrin in several…
This study examines whether inhibitors can participate in degenerate chain branching during hydrocarbon oxidation, using isotactic polypropylene oxidized at 200° in the presence of alkylphenol inhibitors. A kinetic treatment relates the critical inhibitor concentration to the self-acceleration facto…
The paper investigates the kinetics of catalytic deuterium exchange between water vapor and hydrogen for the reaction HDO with hydrogen forming HD and water. Experiments were conducted at atmospheric pressure in a flow circulation system on nickel, cobalt, palladium, copper, silver, and iron oxide c…
This study examines how buffer solution pH affects the liquid phase hydrogenation of several unsaturated compounds, including hexene-1, allyl and cinnamyl alcohols, dimethylethynylcarbinol, and phenylacetylene. Experiments were conducted on skeletal nickel, platinum black, and palladium on barium su…
This study investigates the composition, stability, and charge of vanadylvanadate ions formed between tetravalent and pentavalent vanadium in aqueous solution over a range of pH values. Using spectrophotometry at constant ionic strength, supplemented by electromigration experiments, the authors meas…
The paper describes the synthesis and initial reactivity study of N-vinylthiopyrrolidone, a sulfur-containing analog of N-vinyllactams not previously described in the literature. N-vinylthiopyrrolidone was obtained in up to 60% yield by treating N-vinylpyrrolidone with phosphorus pentasulfide in xyl…
This paper proposes a kinetic interpretation of autocatalysis in polymerization reactions with linear chain termination, distinct from the conventional gel effect associated with radical recombination. It develops a simple scheme in which active centers formed in contact with existing polymer chains…
This study examines how the geometry of thioether radicals affects the anticholinesterase activity of organophosphorus inhibitors that lack heteroatoms in the thioether chain, addressing whether factors beyond positive charge contribute to cholinesterase binding. A series of O-ethyl-S-alkyl methylth…
This paper extends catalytic intramolecular dehydration of furan and tetrahydrofuran amines to tetrahydrofuran diamines as a route to condensed pyrrolidine and piperazine systems. Furfural and methylfurfural derivatives were converted by reductive amination with ethylenediamine and subsequent hydrog…
This study examines how preliminary proton irradiation affects the subsequent thermal decomposition rate of potassium permanganate, motivated by earlier findings that X-rays and gamma radiation accelerate permanganate decomposition. Potassium permanganate samples were irradiated with 4.5 MeV protons…
This paper examines how pressure can directly affect processes in the reaction layer of the condensed phase during gunpowder combustion, rather than influencing burning rate only through heat flux from the gas phase. The authors analyze dispersion caused by gaseous decomposition products dissolved i…
This paper applies a method based on the convergence of solvation energies of isoelectronic cations and anions to separate total solvation energies into contributions from individual ions in a range of aqueous and nonaqueous solvents. Using electromotive force and solubility data of varying reliabil…
This study determines evaporation coefficients for liquid boron trifluoride, boron trichloride, methane, and, for calibration, ethyl alcohol, motivated by their relevance to isotope separation by distillation. The authors use a closed-volume pressure-rise method, deriving coefficients from the linea…
This study examines how micelle formation in dilute aqueous surfactant solutions influences kinetic wetting during impregnation of porous hydrophobic materials. Wetting ability was measured by the time required for hydrophobized cotton fabric or collodion ultrafilters to become saturated, and result…
This study examines equilibrium conditions and phase changes during the reduction of magnesium ferrite by hydrogen at 900°C. Magnesium ferrite prepared from stoichiometric magnesium oxide and ferric oxide was reduced in a closed circulating hydrogen and water vapor system, with equilibrium oxygen pr…
This paper examines the ionic nitration of unsaturated compounds, focusing on nitrofluorination as the conjugate addition of nitronium and fluoride ions to olefins and halogen-substituted olefins. It argues that solutions of nitric acid, dinitrogen tetroxide, potassium nitrate, or dinitrogen pentoxi…
This paper investigates the mechanism by which excited formaldehyde molecules are formed in chemiluminescent oxidation and cold-flame reactions. Using model radical sources, the authors compare proposed elementary processes involving methoxyl, methyl, and hydroxyl radicals, with emission identified …
This study examines the thermal decomposition of ammonium perchlorate single crystals, with emphasis on how reaction centers form and grow in relation to crystal structure and temperature. Using microcinematography and gravimetric kinetic measurements, the authors show that below the phase transitio…
This paper examines the catalytic synthesis of esters of gamma-ketocarboxylic acids through conjugated hydrogenolysis of furan-containing esters. Esters of beta-furylacrylic and beta-furylpropionic acids were prepared from furfural condensation products, selectively hydrogenated where necessary, and…
This study examines the thermodynamic behavior of tin monoxide in SnO-SiO2 melts, a system relevant to tin losses in pyrometallurgical slags. The authors determined SnO activity by an electromotive force method using a concentration cell without transference, after confirming the stability of liquid…
This paper examines mechanoelectron emission, the emission of fast electrons under mechanical action in high vacuum, during adhesive detachment and deformation of polymer films. The authors describe a vacuum apparatus combining mechanical adhesion measurements with electron detection by secondary el…
This study examines the platinum-catalyzed addition of several silicon hydrides to dimethylallylferrocenylsilane as a route to silicon-containing ferrocene derivatives. Dimethylallylferrocenylsilane was prepared from dimethylallylchlorosilane and ferrocenyl lithium, then reacted with trialkylsilanes…
This study uses electron paramagnetic resonance to examine the formation of alcohol radicals during ultraviolet irradiation of alcohol solutions at 77 K. Pure methanol, ethanol, and isopropanol produced only small radical concentrations under full mercury lamp irradiation, whereas solutions containi…
This study examines how the physical state of polymers during contact formation affects adhesion, using the diffusion theory of adhesion as its interpretive framework. Peel resistance measurements for joints between polyethylene and several elastomers show that adhesion increases with contact time a…
This paper examines the preparation of polymers and copolymers containing ferrocene units by the polyrecombination method. Alkyl and cyano derivatives of ferrocene, including isobutylferrocene, diisobutylferrocene, isoamylferrocene, and cyanoferrocene, were reacted with tert-butyl peroxide, and copo…
This study examines whether high pressure can alter the structural orientation of the radical phenylation of tert-butylbenzene with benzoyl peroxide, a reaction in which ortho substitution is normally suppressed by steric hindrance. Using gas-liquid chromatography, the authors measured the isomeric …
This paper examines how adsorption modification of dispersed quartz by octadecylamine affects structure formation in quartz suspensions and rubber solutions. Adsorption from p-xylene was measured directly by interferometric and colorimetric methods and compared with the limiting shear stress of conc…
