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 examines the catalytic behavior of zirconium phosphate in model reactions involving dehydration, isomerization, esterification, alkylation, ketonization, and dehydrogenation. Two preparations with markedly different surface areas and acidities were compared, showing that the more acidic, …
Photoemission from dilute sodium and cesium amalgams was measured over specified concentration ranges and between 25 and minus 80 degrees Celsius, extending earlier work on potassium amalgams. The authors compare concentration dependences of photocurrent, electron work function, and surface tension,…
This paper examines chemical interaction and thermal stability in liquid Ge-Te, Sn-Te, and Pb-Te binary systems, focusing on compounds of the type GeTe, SnTe, and PbTe relevant to thermoelectric materials. Using physicochemical analysis, the authors measured viscosity and electrical conductivity of …
This study examines whether the porous structure of solid acidic catalysts influences the acid heterogeneous isomerization of alpha-pinene and the distribution of bicyclic, tricyclic, and monocyclic terpene products. Aluminosilicic acids deposited on silica gel supports with different pore radii, po…
This study examines radiation polymerization of vinyl oleate in relation to the phase state of the monomer, with particular attention to polymerization in a liquid-crystalline medium where molecular orientation is retained without the stresses of a true crystal lattice. Thermographic and polarizing …
High-resolution proton NMR spectra were measured for a series of mono- and heteroannular disubstituted ferrocene derivatives to examine how substituents affect hydrogen atoms in different positions of the cyclopentadienyl rings. The spectra are classified according to substituent electronic characte…
This study examines how electron donors and acceptors deactivate the excited singlet and triplet states of magnesium phthalocyanine in deoxygenated dioxane solution. Using flash photolysis to follow triplet, triplet absorption at 470 nm and separate fluorescence quenching measurements, the authors c…
This paper investigates catalytic reduction of the carbonyl compound fluorenone by the NADH model 2,6-dimethyl-3,5-dicarboethoxy-1,4-dihydropyridine. Experiments in alcoholic sodium ethoxide under inert atmosphere show that fluorenone is not reduced by the dihydropyridine alone or by sugars alone, b…
This study examines the photochemical hydrobromination of allyl chloride with hydrogen bromide in glassy and crystalline mixtures irradiated at 77 K and then warmed. Using gas chromatography and differential thermal analysis, the authors identify 1-chloro-3-bromopropane as the principal product and …
The paper examines the reaction of barene and substituted barenes with amines, challenging earlier interpretations that stable amine adducts are formed without degradation of the boron cage. Experimental reactions with piperidine and other amines in hydrocarbon and alcoholic media show cleavage of t…
This study examines the mechanism and regioselectivity of the addition of phosphorus trichloride and phosphorus acid chlorides to propylene oxide, addressing conflicting earlier interpretations of the reaction products. Experiments with dried reagents, atmospheric moisture, added water, and triethyl…
This study examines whether carbonaceous deposits formed by propylene polycondensation on silica gel can alkylate benzene, and whether such behavior supports a demethanation stage in carbide formation. Flow experiments at 500 to 900°C compared propylene, benzene, their mixtures, and benzene passed o…
This paper applies the energetic form of multiplet theory to oxidation catalysis, relating catalyst specificity to bond energies between the catalyst and oxygen, hydrogen, and carbon atoms or groups in reacting organic molecules. Using literature activation energies for oxygen isotope exchange, hydr…
This paper investigates detonation combustion in heterogeneous systems consisting of thin petroleum oil films on tube walls in gaseous oxygen at atmospheric pressure. Using high-speed photographic recording in steel tubes, the authors examine initiation by strong sources and by transfer from a prefo…
Cycloalkano-2,3-pyrrolidines, including cyclopentano derivatives and perhydroindoles, were synthesized from monocyclic gamma-keto alcohols and gamma-keto halides using formamide and N-substituted formamides under Leuckart reaction conditions. The study proposes a sequence involving reductive aminati…
This study examines the crystal-chemical limits for forming garnets that contain large cations in dodecahedral, octahedral, and tetrahedral positions. Guided by ionic-radius considerations, stoichiometric oxide and carbonate mixtures were fired in air and selected compositions were also tested hydro…
This paper investigates whether combustion in pure acetylene can spontaneously transition to detonation at initial pressures near and below the previously accepted lower limit. Experiments were conducted in long steel tubes using weak spark initiation, thermocouple records of reaction-zone motion, a…
This paper examines the reaction of phosphorus pentasulfide with alcohols and phenols in the presence of bases, motivated by the hypothesis that its behavior parallels that of phosphorus pentoxide with hydroxyl compounds. Using triethylamine, potassium hydroxide, or potassium alcoholates, the author…
This paper examines the role of transition metal pi complexes in the stereospecific polymerization of butadiene, contrasting these systems with coordination anionic catalysts that require metal carbon sigma bonds. Using catalytic systems based on cobalt, nickel, vanadium, molybdenum, and related Lew…
This study applies electron paramagnetic resonance radiospectroscopy to a rarefied hydrogen sulfide flame in order to identify transient atoms and radicals relevant to the still uncertain oxidation mechanism of hydrogen sulfide. Using heated resonator and reactor arrangements that allowed the flame …
This study examines whether substituent effects are transmitted with equal efficiency in cis and trans cinnamic acids. Dissociation constants of substituted cis and trans cinnamic acids, and of corresponding benzoic acids, were measured potentiometrically in 49% ethanol at 25 °C and analyzed using H…
This study examines whether supramolecular ordering in solutions of crystallizing polymers affects crystallization kinetics, using the induction period as an indicator of solution structure. A depolarized light method with crossed polarizers was applied to dilute fractionated linear polyethylene sol…
This paper reports synthetic approaches to the glyceride basis of vegetable oils and animal fats, focusing on higher fatty acids and triglyceride mixtures that reproduce natural lipid compositions. The authors describe syntheses of saturated and unsaturated fatty acids, preparation of more than 80 t…
This paper examines the role of electronic n to pi* transitions in ionization and fragmentation processes of molecules containing carbonyl chromophores, with particular attention to anthraquinone and fluorenone. Ionization curves and ion appearance potentials were measured by electron impact mass sp…
High-resolution proton NMR is applied to mono- and dicyclopentadienyl titanium derivatives to examine how substituents on titanium affect the nature of the titanium, cyclopentadienyl bond. The study compares chemical shifts for ring and alkoxy protons across chloro, alkoxy, acyloxy, and substituted …
The study examines the substitution of bromine in bromoferrocene by aromatic and heterocyclic groups through reactions with organomagnesium compounds in the presence of cuprous bromide and copper. Under nitrogen and heating after removal of ether, aryl and heteroaryl Grignard reagents gave phenylfer…
The paper examines the structure and solution behavior of the congruently melting complex compound BeCl2·AlCl3·3(C2H5)2O, previously observed in the system of beryllium and aluminum chloride etherates. Using infrared spectroscopy of related beryllium and aluminum halide etherates, chloroaluminates, …
This paper examines the mechanisms and stereochemical outcomes of electrophilic and homolytic substitution at olefinic carbon atoms, using stereoisomeric beta-chlorovinyl and omega-bromostyryl organomercury compounds. Kinetic measurements and stereochemical analyses show that bimolecular electrophil…
This paper investigates the crystallographic location of silver ions in synthetic zeolite AgX, a material of interest because ion exchange strongly affects zeolite adsorption properties. An NaX zeolite in which 80 percent of sodium ions had been replaced by silver was examined by powder X-ray diffra…
This paper investigates whether individual nonionized molecules with masses smaller than those of the condensing vapor can initiate condensation in a metastable supersaturated vapor. Using continuous gas-flow experiments with supersaturated dioctyl sebacate vapor, photochemically generated iron nona…
This paper reports experimental phase equilibrium diagrams for the sodium chloride, water and potassium chloride, water systems at elevated temperatures and pressures, where sparingly volatile salts dissolve in aqueous vapor and strongly affect system properties. Measurements of vapor and liquid com…
Experiments were conducted on the condensation of aluminum vapor on glass through diaphragms in vacuum, with deposit density measured photometrically and structure examined by electron microscopy. The authors observed blurred shadow images, delayed deposit formation, reflection of aluminum species f…
This paper reports thermochemical measurements for barium germanates, motivated by the lack of formation enthalpy data for compounds that are crystal-chemical analogs of silicates. Using solution calorimetry at 50 degrees Celsius in a nitric acid and hydrofluoric acid solvent, the authors determined…
This study examines the electronic influence of 2-furyl, 2-thienyl, and 2-selenienyl radicals on the basicity of chalcone analogs, addressing contradictory reports on whether these heterocycles act as electron donors or acceptors. The authors measured protolytic equilibrium constants in sulfuric aci…
This study describes the synthesis of previously little-studied 3-oxa-1,5-keto alcohols through catalytic hydrogenolysis of acetates of monofurfuryl ethers of 1,2-glycols over platinized charcoal. The principal reaction cleaves the furan ring at the 1,5 C-O bond to give acetates of 5-keto-3-oxa-octa…
Rare-earth formates of yttrium, lanthanum, and the lanthanoids from praseodymium to holmium, excluding promethium, were synthesized and examined to clarify relationships between composition, structure, solubility, density, and thermal behavior. X-ray analysis showed that the lanthanum to holmium for…
This paper develops a gas liquid chromatographic approach for estimating thermodynamic functions of interaction between solutes and polar solvents, distinguishing solute solvent interaction from solvent self-association. The authors derive relations between chromatographic distribution coefficients,…
This paper examines criteria for assessing polymer compatibility and argues that deviations of mixture properties from additive behavior, especially solution viscosity, are not reliable evidence of incompatibility. Using fractions of the same polyethylene sample as a model compatible system, the aut…
The study examines the polymerization of 3,4-benzo-1,1-dimethylsilacyclopentane through cleavage of the silicon carbon bond in the heterocycle. Polymerization with aluminum chloride at 50 to 100°C gave viscous low molecular weight oils, while metallic potassium in tetrahydrofuran at about minus 100°…
This study examines the photochemical reduction of hydrogenated tetraphenylporphin derivatives, primarily tetraphenylchlorin and tetraphenylbacteriochlorin, in pyridine solutions with hydrazine, and compares the behavior of tetraphenylchlorin with hydrogen sulfide. Visible and infrared absorption sp…
This study examines whether calcium phosphate can be thermally dissociated in the presence of silica to obtain phosphorus pentoxide directly, avoiding reduction to elemental phosphorus and subsequent oxidation. The authors combine thermodynamic calculations for several calcium phosphate and apatite …
This study examines the electron-impact mass spectra of three methylated methyl deoxyhexosides, bearing deoxy substitution at the 2, 3, or 4 position, in order to clarify fragmentation behavior and assess analytical differentiation of deoxy sugars. The compounds were synthesized, checked for homogen…
This study examines how the composition of neodymium-activated silicate and germanate glasses affects their absorption spectra and luminescence lifetimes, with attention to the ratio of glass-forming oxides to alkali modifiers and to neodymium concentration. Simple binary systems based on sodium sil…
This paper examines the thermodynamic behavior of the MnO, FeO solid solution, addressing conflicting earlier conclusions about whether the system behaves ideally. Using equilibrium gas phase compositions for hydrogen reduction at 900, 1000, and 1100 °C, the authors calculate component activities wi…
This study examines the acidity function and catalytic activity of hydrogen counterions in strongly acidic sulfopolystyrene cation exchangers, comparing them with hydrogen ions in sulfuric acid solutions. The authors develop a spectrophotometric adaptation of the Hammett indicator method using nitro…
This study examines relaxation phenomena in crystalline polycaproamide samples with similar spherulitic structure but different degrees of crystallization, prepared by pressing and, for one series, additional heat treatment. Thermomechanical measurements over a range of temperatures and force freque…
This study examines the isomerization of tertiary beta-acetylenic alcohols bearing ferrocenyl and cyclopentadienylmanganese tricarbonyl substituents. The alcohols were prepared by Grignard reaction and converted under mercury sulfate, acid, or dehydration conditions to the corresponding conjugated e…
This paper examines the role of soluble organoaluminum compounds in the stereospecific polymerization of isoprene using a titanium tetrachloride and triisobutylaluminum complex catalyst. Through washing, reactivation, impurity, and vacuum experiments, the authors compare catalyst activity after remo…
This article reassesses the prevailing view that the conjugated bond systems in humic coals are fundamentally aromatic. By comparing evidence from coalification, oxidation products, halogenation and sulfonation behavior, magnetic susceptibility, infrared and ultraviolet spectra, optical anisotropy, …
This paper reports the preparation of mercurated phosphonium salts by addition of mercuric chloride to several triphenylphosphorane Wittig reagents, giving crystalline compounds with defined elemental compositions. Their reactions with ammonia, thiosulfate, aldehydes, phenylboronic acid, acid chlori…
