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 paper examines the thermodynamics of molten lanthanum chlorides, including the unstable dichloride whose independent existence was uncertain, using electrochemical measurements in equilibrium LaCl2, LaCl3 melts in contact with liquid lanthanum. The authors measure the emf of a cell with lanthanu…
This study investigates intermolecular electron transfer in binary molecular solutions during pulsed photoexcitation, using perylene as an electron acceptor or donor because its radical ion spectra are accessible. A high speed photoelectric spectrometer was used to record transient absorption spectr…
This study examines the anodic condensation of sodium monomethyl adipate under aqueous and alcoholic conditions optimized for producing dimethyl sebacate, with attention to the formation of by-products that complicate the Brown-Walker electrosynthesis scheme. Electrolyses were performed with platinu…
This paper reports the preparation and characterization of isotopically substituted organolithium compounds intended for structural studies of ethyllithium and phenyllithium derivatives. Deuterated ethyllithiums were synthesized from corresponding deuterated ethyl chlorides and lithium, while lithiu…
This study examines how adsorption affects the kinetics of quinone reduction and hydroquinone oxidation at a platinum electrode. Using rotating platinum electrodes, polarization measurements, and radioactive tracer measurements for bromide and iodide adsorption, the authors compare the effects of ad…
This study examines whether non-stratifying liquid mixtures can develop concentration fluctuations comparable to those near critical opalescence in phase-separating systems. Using photoelectric nephelometry with high-precision temperature control, the authors measured light scattering intensity and …
This study examines intermolecular excitation energy transfer from the uranyl cation to metal-free and magnesium phthalocyanines in solution and on magnesium oxide adsorbents. Using low-temperature and room-temperature luminescence spectroscopy with selective excitation of uranyl absorption bands, t…
This study examines the quasilinear absorption and fluorescence spectra of porphine and dihydroporphine, or chlorin, in frozen normal hydrocarbon matrices at 77 K using the Shpol’skii method. By resolving low-temperature spectra, the authors determine vibrational frequencies active in electronic tra…
Electron paramagnetic resonance spectra of alpha,alpha-diphenyl-beta-picrylhydrazyl and 2,2,6,6-tetramethylpentamethylene nitroxide were studied in liquid and supercooled solutions between 77 and 300 K to examine how the local solvent environment affects hyperfine structure. Using polar and nonpolar…
This paper analyzes the problem of thermal explosion initiated by a localized hot spot in a reactive medium, formulated as a spherically symmetric heat conduction and chemical kinetics problem with an initial step-like temperature profile. Numerical solutions are used to determine critical condition…
This study examines whether the previously observed peroxide-induced radical rearrangement of mercaptals and mercaptols with arylthio migration can also occur with migration of an alkylthio group. Acetone di-n-butylmercaptal was heated in chlorobenzene with tert-butyl peroxide, and the products were…
This study examines cobalt, kieselguhr catalysts promoted with zirconium dioxide or titanium dioxide together with magnesium oxide for the synthesis of higher hydrocarbons from carbon monoxide and hydrogen. Flow experiments at atmospheric pressure and at 10 atm compared catalyst activity, stability,…
This paper reports the synthesis of nitrogen- and oxygen-containing polymers with conjugated C=N bonds from inorganic salts, using ammonium chloride with sodium carbonate or sodium bicarbonate in the presence of zinc chloride. The reactions were conducted in sealed autoclaves at 250 to 300°C under p…
The study examines anodic oxidation of formic acid and formate salts on a rotating smooth platinum electrode using compensated polarization measurements and polarographic recording. Polarization curves show multiple current maxima and inhibition regions whose potentials are largely independent of fo…
This study examines the separation of isotopic hydrogen molecules on synthetic type A zeolites in which sodium ions were partially replaced by cobalt ions. Cobalt exchanged zeolite samples with varying cobalt contents were prepared, characterized by X-ray diffraction and nitrogen sorption, and teste…
This paper examines how proton affinity can be used to characterize the acidity and basicity of nonaqueous solvents. It argues that solvent basicity is reflected in the solvation energy of protons and formation of solvated lyonium ions, while acidity is better characterized by the affinity of solvat…
This study examines the radiation-induced oxidation and reduction of variable-valence inorganic acceptors in acetone solutions, motivated by unusually high yields previously observed for methylene blue systems. Dilute deaerated or oxygen-containing solutions of iron, copper, chromium, manganese, and…
This paper examines nitrosochlorination of olefins and haloethylenes by an ionic mechanism, addressing the difficulty of adding nitrosyl chloride to less reactive halogenated ethylenes and the unusual orientation observed in chloroethylene derivatives. The author argues that aprotic Lewis acids such…
This paper examines the synthesis of ferrocene-based polymers by peroxide-induced polyrecombination and acid-catalyzed polycondensation, including systems involving tert-butylferrocene, halogenated aromatic compounds, acetone, and acetylferrocene. The authors describe reaction conditions, yields, so…
This paper examines how solvent nature affects the thermal effects of dissolution and swelling in divinylstyrene and divinylnitrile copolymers. Heats of dissolution were measured calorimetrically at 25°C, and polymer solvent densities were determined by the gradient tube method, with results compare…
This paper formulates the use of a perturbation method for calculating the frequencies and forms of normal vibrations of polyatomic molecules. The molecular vibration operator is represented as a zeroth approximation describing noninteracting coordinate groups plus a perturbation describing their in…
This preliminary study reports measurements of the double electric layer capacitance at a platinum electrode in a solid ZrO2 and CaO electrolyte. Cylindrical electrolyte pellets with platinum electrodes were examined in purified argon at about 1020 degrees C using an impedance bridge, with capacitan…
This paper examines whether molecular-colloidal impurity centers in optically unsensitized photographic emulsions act as electron donors and whether they produce short-wavelength impurity photosensitivity in addition to long-wavelength sensitivity. Using a differential spectrosensitometric method, t…
This study examines whether trivalent iron in molten silicates exists predominantly as complex anions, free cations, or an equilibrium of both forms. Using a modified Frumkin electrocapillary method, the authors measured the pressure required to detach nitrogen bubbles from a polarized platinum capi…
Electron paramagnetic resonance was used to study primary radical products formed during low-temperature gamma radiolysis of purified piperidine, both in vacuum and in the presence of oxygen. Irradiation at 77 K produced a stable spectrum interpreted as a doublet of triplets, with radical accumulati…
This paper investigates the formation and decomposition of covalent phenyl derivatives of titanium, motivated by earlier unsuccessful attempts and by evidence for transient organotitanium species in catalytic systems. Reactions of titanium tetrachloride with diphenylmercury and phenyllithium were ex…
This paper examines the activities of lithium, potassium, rubidium, cesium, and ammonium chlorides in aqueous sodium chloride solutions under isopiestic conditions at 25 degrees Celsius. Using the McKay and Perring differential equation, the authors relate salt activities to the dependence of total …
This study examines the addition of triethylgermane to several tertiary vinyl ethynyl carbinols in the presence of Speier’s catalyst and the subsequent dehydration of the resulting diene germanium-containing carbinols. Dimethyl, methylethyl, tetramethylene, and pentamethylene substrates were convert…
This study examines how the acidity of cobalt sulfate electrolytes affects the microstructure, adsorption behavior, and self-dissolution of electrolytic cobalt deposits. Cobalt was deposited at pH 1.5 to 5.1 under controlled conditions, then characterized by microphotography, dissolution in sulfuric…
This study investigates the normal flame velocity of pure acetylene decomposition as a function of initial pressure at 18 to 20°C over 2.5 to 5.0 atm. Using a large receiver to minimize pressure rise, photographic recording to measure visible flame speed, and ionization probes to reconstruct the fla…
This study examines how the mechanical properties of KU-2 sulfonated cation-exchange resin grains influence the sorption of methylene blue ions and the formation of pseudoequilibrium states. The authors measured reversible deformation under load for resins containing 2% and 6% divinylbenzene at diff…
The paper examines the chain formation and chain consumption of alcohols during liquid-phase oxidation of n-decane, focusing on the activation energies of the elementary reactions involving peroxy radicals, hydroperoxides, and alcohols. Using an open-flow oxidation system, the authors compare steady…
This study examines the nonadditive action of amine and phenolic inhibitors during the initiated oxidation of ethylbenzene at 70°C, a model unbranched chain oxidation system. By following inhibitor concentrations spectrophotometrically and measuring rate constants for reaction with peroxy radicals b…
This study examines the radiolysis of aqueous sulfuric acid over a concentration range of 0.4 to 18 M, separating direct radiation effects on sulfuric acid from indirect effects mediated by water radiolysis products. Solutions containing ferrous ions were irradiated with x-rays and cobalt-60 gamma r…
This study examines the cathodic reduction of the singly charged permanganate anion at a dropping mercury electrode, focusing on the origin of the current minimum observed at negative surface charges. Polarization curves, drop-growth current measurements, and differential capacitance measurements we…
This study examines the formation of polybenzimidazoles through the polycondensation of 3,3′-diaminobenzidine with diphenyl sebacinate, with attention to reaction temperature, time, pressure, reagent imbalance, and monofunctional additives. The authors characterize the resulting polymers by solution…
This study examines the thermal stability and decomposition behavior of high purity sodium aluminum hydride, information needed for preparing alkali metal aluminum hydrides and for interpreting reactions involving them. Sodium aluminum hydride prepared by a modified Klassen method was analyzed by di…
This study examines radiation-induced polymerization of tetrafluoroethylene in the solid state, a process previously less characterized than gas- and liquid-phase polymerization. Purified, deoxygenated monomer was irradiated at low temperatures with gamma rays and fast electrons, and polymer yields,…
This study examines interactions of uranium oxides with vanadium and niobium oxides using thermal analysis, X-ray phase analysis, infrared spectroscopy, and limited single-crystal methods. Hydrous uranyl vanadates were found to form broad homogeneity regions, and heating or reduction produced severa…
This study examines how neutral electrolytes affect coagulation interactions in concentrated model suspensions of nearly monodisperse glass spheres in water. Using limiting shear stress measured with a sensitive cone plastometer as an indicator of coagulation structure, the authors relate changes in…
The study examines why the radiolytic oxidation yield of divalent iron in oxygen-containing sulfuric acid solutions decreases at high absorbed-dose rates. Ferrous sulfate solutions of varying iron, oxygen, acid, and sodium chloride concentrations were irradiated with short high-intensity electron pu…
This paper examines regularities in complex formation by pentavalent actinides, focusing on protactinium, neptunium, and plutonium with anions of organic and inorganic acids. Using ion-exchange data and reported instability constants, the authors compare complex compositions and stabilities, showing…
This paper develops a general kinetic formulation for stationary and quasi-stationary complex reactions composed of elementary stages, including heterogeneous reactions on homogeneous surfaces. It defines reaction routes through stoichiometric numbers, relates route rates to forward and reverse rate…
This paper examines the polymorphism of lanthanum oxide and the conditions required to obtain its low-temperature cubic form, whose existence had been uncertain in earlier studies. Lanthanum carbonate, oxalate, hydroxide, and nitrate were decomposed under high vacuum, with products characterized by …
This study examines the electronic effects of aromatic substituents containing a trifluoromethyl group using the Hammett-Taft separation of substituent constants into inductive and conjugation components. Meta and para Hammett constants were derived from ionization measurements of substituted benzoi…
This paper examines elementary reactions of molecular fluorine that generate atoms and radicals, focusing on additions to olefins and hydrogen abstraction from hydrogen iodide. Using low temperature surface reactions, BET surface measurements, and diffusion flame methods, the authors determine kinet…
This study examines how the electrical double layer and solution pH influence hydrogen overvoltage on gallium, using liquid, solid, and dropping gallium electrodes in acidic chloride and sulfate solutions. Measurements of overvoltage as a function of electrolyte concentration and pH showed changes o…
This study examines the nature of higher surface oxides of platinum formed during anodic discharge of hydrogen peroxide in acidic electrolyte. Using oxygen isotope labeling with hydrogen peroxide enriched in oxygen-18 and mass-spectrometric analysis of anodically evolved oxygen, the authors tested w…
Mössbauer absorption spectra were measured for three iron(II) complexes with diacetylthiosemicarbazone oxime derivatives in order to assess how proton removal and changes in ligand bonding affect the electric field at the iron nucleus. Using a cobalt-57 in chromium source, spectra were recorded at r…
This communication addresses the synthetic construction of the labile DCB ring system of tetracyclines, a key obstacle in routes to natural tetracycline antibiotics. Starting from an acetoxyketodiol derived from juglone, the authors examine protective-group strategies, Grignard addition, hydrolysis,…
