Recent Papers

Reaction of diphenyliodonium borofluoride with aliphatic amines

The study examines the reaction of diphenyliodonium borofluoride with aliphatic amines under varied solvent and temperature conditions, contrasting it with previously observed arylation behavior of diaryliodonium salts. Experiments with diethylamine and triethylamine showed rapid decomposition of th…

On the Mechanism of Zirconium Dissolution in Acidic Fluoride Solutions

This study examines the mechanism of zirconium dissolution in acidic fluoride solutions, focusing on the relation between metal dissolution, hydrogen evolution, stirring, hydrofluoric acid concentration, and electrode potential. Using potentiostatic measurements and colorimetric determination of dis…

On the Reduction of Technetium(VII) by Hydrochloric Acid

This paper investigates the poorly understood reduction of pertechnetate, technetium(VII), in hydrochloric acid, with attention to acid concentration, time, temperature, and possible intermediate oxidation states. Spectrophotometric measurements in concentrated hydrochloric acid were combined with e…

Thallium chalcogen halides

This paper reports the synthesis and characterization of thallium chalcogenohalides formed by adding sulfur or selenium to monovalent thallium halides. Equimolar mixtures of thallium chloride, bromide, or iodide with sulfur or selenium were heated in sealed ampoules, and the products were examined b…

Phase Equilibria in the Systems $\mathrm{UO}_2\mathrm{SO}_4$ – $\mathrm{H}_2\mathrm{O}$ – BEDPA, $\mathrm{H}_2\mathrm{SO}_4$ – $\mathrm{H}_2\mathrm{O}$ – BEDPA

This study examines phase equilibria at 25 degrees C in the ternary systems uranyl sulfate, water, BEDPhK and sulfuric acid, water, BEDPhK, as components of a quaternary extraction system relevant to uranium(VI) sulfate solutions. Solubility isotherms were determined by equilibrating aqueous and org…

Molecular sieve properties of synthetic zeolites of types $\mathrm{A}$, $\mathrm{X}$ and $\mathrm{Y}$ in various ion-exchange forms

This paper examines the molecular sieve behavior of synthetic zeolites A, X, and Y in sodium, potassium, and calcium ion exchange forms, emphasizing that effective window diameters are kinetic quantities governed by activation barriers for molecular penetration. Using structural considerations of cu…

On the Minimum Information Sufficient for Identifying Individual Organic Properties from Coincident Lines in Mass Spectra

This paper examines whether individual organic compounds can be identified from a minimal set of noncharacteristic mass spectral lines, particularly for use with chromatographic detection. Using about 900 organic mass spectra, the authors analyze intensity ratios in the 36 to 45 a.m.u. region and de…

Capacitance, resistance, and injection coefficient of a semiconductor electrode in redox reactions

This paper analyzes the small-signal electrochemical behavior of a semiconductor electrode in oxidation-reduction reactions, emphasizing the role of the injection coefficient, defined as the fraction of minority-carrier current in the total current. Using diffusion equations for electrolyte species,…

Interaction of Thiourea with Organic Sulfides, Disulfides, and Sulfenyl Chlorides in an Acidic Medium

This study examines the reaction of thiourea with organic sulfides, disulfides, and sulfenyl chlorides in acidic media, extending earlier work on analogous reactions of ethers. Experiments with tert-butyl, n-butyl, isobutyl, and phenyl sulfur compounds show that sulfides may give either S-alkylisoth…

Corrections to the Article “On the Representation of the Transition Function of a Machine by Associative Operations” (DAN, Vol. 150, No. 2, 1963)

Temperature changes of the long period in oriented polymers

Small-angle X-ray scattering was used to examine temperature-dependent changes in the long period of highly oriented low-pressure polyethylene fibers during repeated heating and cooling between room temperature and about 116 degrees C. The first heating cycle produced irreversible structural changes…

Temperature Dependence of Double-Layer Capacitance in Molten Oxides

The study examines the temperature dependence of electrical double layer capacitance at the interface between liquid carbon saturated iron and molten calcium aluminosilicate or aluminate electrolytes at 1300 to 1600 degrees Celsius. Using alternating current polarization and frequency extrapolation …

Galein: A New Flavonoid from Goat's Rue, Galega officinalis L.

This study reports a chemical investigation of the flowers of goat’s rue, Galega officinalis L., a plant previously examined mainly for constituents of its seeds and herb. Ethanol extraction yielded a crystalline flavonoid glycoside named galein, which on acid hydrolysis produced the aglycone galeti…

On the mechanism of formation of hydrocarbons with a six-membered ring during the catalytic hydrocondensation of carbon monoxide with cyclopentene

This paper examines the mechanism by which hydrocarbons containing a six-membered ring form during catalytic hydrocondensation of carbon monoxide with cyclopentene over a cobalt catalyst in the presence of hydrogen. To test an earlier hypothesis that methylenecyclopentane is an intermediate that sub…

Phase of the Second Harmonic of the Alternating Potential and Transfer Coefficients of Fast Electrochemical Reactions

This paper proposes a method for determining the transfer coefficient of fast electrochemical oxidation, reduction reactions at low alternating-current frequencies. The authors analyze the phase shift of the second harmonic of the alternating electrode potential relative to a sinusoidal polarizing c…

On the Mechanism of Radiolysis of Dilute Aqueous Nitrate Solutions

This study examines the mechanism of gamma radiolysis in dilute aqueous sodium nitrate solutions, with attention to the roles of hydrated electrons, hydrogen atoms, hydroxyl radicals, oxygen, and pH. Product yields of nitrite, hydrogen peroxide, and hydrogen were measured in deaerated, air-saturated…

Triplet Molecules in Liquid Benzene. Photochemical Processes in a Thin Absorbing Layer

This paper investigates the formation and behavior of triplet benzene molecules in liquid benzene, a system in which direct phosphorescence and triplet absorption are not readily observed. The study uses photosensitized trans to cis isomerization of stilbene in air-free benzene solutions as an indir…

EPR Spectra and Transmission of Substituent Effects in Anion Radicals of para-Nitrodiphenyls

This study examines how para substituents affect electron-density distribution in anion radicals of substituted para-nitrobiphenyls and how insertion of a second benzene ring modifies transmission of substituent effects. Polarographic half-wave potentials and electron paramagnetic resonance spectra …

Low-Temperature Oxidation of Carbon Monoxide by Aqueous Solutions of Palladium Salts

This study examines low-temperature liquid-phase oxidation of small concentrations of carbon monoxide using aqueous palladium salt catalysts in a flow system at 20 and 40°C. The authors test the effects of added oxidants, including copper, iron, hydrogen peroxide, and chromium compounds, as well as …

Statistical Theory of Nonequilibrium Processes at the Metal–Solution Interface. Statistical Theory of the Nonequilibrium Double Layer

This paper develops a statistical formulation of nonequilibrium processes at the metal electrolyte interface, focusing on the electrical double layer beyond the Gouy Chapman Stern approximation. Using generalized correlation functions and a Fokker Planck description of ionic motion, the authors deri…

Dissociation cross section of $\mathrm{H}_2^+$ ions from methane and n-butane at various electron energies

This study examines how the dissociation cross sections of H2+ ions formed by electron impact from methane and n-butane depend on the energy of the ionizing electrons. Using a double mass spectrometer with neon as the collision gas, the authors measured dissociation of 3.8 keV H2+ ions and compared …

Excitation of Triplet States of Naphthalene Molecules in Solid Solutions by Fast Electrons

This study investigates whether naphthalene molecules in solid polymer solutions are excited to triplet states during irradiation by fast electrons, a process previously difficult to observe because of recombination luminescence. Using electron paramagnetic resonance at 100 K, the authors examined n…

Study of the relative reactivity of 1,3-butadiene and 1- and 2-butenes in cationic polymerization

The study examines the relative reactivity of 1,3-butadiene, 1-butene, and cis- and trans-2-butene in cationic copolymerization. Using C14-labeled butadiene, the authors determined copolymer compositions at low conversion in ethyl chloride and toluene solutions with aluminum ethyl dichloride based c…

On the structural orientation of the reaction of diketene with monosubstituted ureas

This study examines the structural directionality of diketene addition to monosubstituted ureas, focusing on whether acetoacetylation occurs at the unsubstituted or substituted nitrogen. Alkylureas were reacted with diketene under different media, including pyridine, chlorobenzene with pyridine, and…

On the Osmotic Theory of Solutions

This note addresses the statistical mechanical formulation of the osmotic theory of solutions, in which the thermodynamics of a solution can be expressed through properties of the dissolved substances. For monatomic molecules with pairwise interactions, it derives expressions for the activity coeffi…

On the Induced Reactivity of Certain Compounds with a Conjugated System in Reaction with 1,1-Diphenyl-2-picrylhydrazyl

The study examines the induced reactivity of polymeric and monomeric compounds with conjugated systems toward 1,1-diphenyl-2-picrylhydrazyl in solution, with particular attention to the role of paramagnetic centers. Using electron paramagnetic resonance, spectrophotometry, chromatography, and ebulli…

Mechanism of the Effect of Ultrasonic Vibrations on the Processes of Coagulation Structure Formation in Aqueous Clay Dispersions

This study examines how ultrasonic oscillations affect coagulation structure formation in aqueous dispersions of Cherkassy montmorillonite and palygorskite, montmorillonite clays. Using structural mechanical measurements, X-ray structural analysis, and electron microscopy, the authors relate changes…

Nuclear Magnetic Resonance in Polymers with a System of Conjugated Bonds

In the article by I. V. Gostunskaya, V. A. Mironov, N. B. Dobroserdova, and B. A. Kazanskii, “On the Chemical Nonequivalence of Active Hydrogen Sorbed by a Skeletal Nickel Catalyst,” published in DAN, vol. 153, no. 5, 1964, in Table 1, in the column “hexene-1 sample weight,” instead of the printed 0.33 g, read: 3.3 g.

On the mechanism of porphyrin regeneration after the photoreduction reaction

This study examines the regeneration of porphyrins after reversible photoreduction, using spectral and kinetic measurements on mesoporphyrin, protoporphyrin, tetraphenylporphyrin, and tetraazaporphin in alcohol, pyridine media with reducing agents such as ascorbic acid or hydrogen sulfide. The autho…

Kinetics of the polymerization of acetylenic hydrocarbons initiated by azobisisobutyronitrile

The paper examines the radical polymerization kinetics of phenylacetylene and related acetylenic hydrocarbons initiated by azoisobutyric acid dinitrile, focusing on features not complicated by chain decomposition of the initiator. Volumetric measurements of initiator decomposition and polymerization…

On stereospecific effects in interfacial polycondensation

The study examines whether changing interfacial polycondensation from a liquid, liquid boundary to a liquid, crystalline boundary affects stereospecific incorporation of enantiomeric monomers. Polyamides were synthesized from optically active 1,2-l-propylenediamine and racemic trans-cyclopropanedica…

Vincarine—a new alkaloid from the roots of Vinca erecta Rgl. et Schmalh

The paper reports the continued separation of alkaloids from the roots of Vinca erecta and describes the isolation of a new crystalline base, named vincarine. Elemental analysis, thin-layer chromatography, acetylation, Kuhn-Roth oxidation, and infrared and ultraviolet spectroscopy are used to charac…

Study of the Catalytic Oxidation of Ammonia on Platinum by the Secondary Ion Emission Method

This study examines the catalytic oxidation of ammonia on platinum at low pressure using secondary ion emission mass spectrometry, comparing surface-emitted ions with ions formed from the surrounding gas phase. The authors report formation of water, nitrogen, and nitric oxide beginning near 200 degr…

A New Reaction for the Formation of Stable Wurster Salts

This paper reports a reaction in which stable Wurster-type cation radicals are formed by interaction of organic free radicals with N,N′-disubstituted p-phenylenediamines in acidic ethanol, acetic acid medium. The authors examined nine p-phenylenediamine derivatives with aroxyl, diarylpicrylhydrazyl,…

On the Reactivity of Alkenylmethylsiloxanes in Reactions with Diazomethane and Phenyl Azide

This study examines how the position of alkenyl groups relative to silicon affects the reactivity of organosiloxanes in additions with diazomethane and phenyl azide, and in a Diels-Alder reaction with butadiene-1,3. Vinylheptamethylcyclotetrasiloxane and 3-vinylheptamethyltrisiloxane readily formed …

X-ray $K$ emission spectra of titanium in lower oxides $(\mathrm{Ti}-\mathrm{TiO}_{0,48})$

This study investigates the electronic structure and bonding in lower titanium oxides within the homogeneity range Ti to TiO0.48 using X-ray K-emission spectroscopy. Fluorescence spectra were recorded for titanium and several oxygen solid solutions, and changes in the titanium K beta and K alpha lin…

Early Stages of Crystallization as a Method for Establishing the Heterogeneity of Crystal Surfaces

This paper examines whether the earliest stages of chemically induced crystallization can serve as an electron-microscopic decoration method for identifying active sites on crystalline surfaces. Lead sulfide was deposited slowly from aqueous solution onto silicon single crystals grown by the Czochra…

Effect of the Phase State on the Nature of Reactions of Tritium Recoil Atoms in Cyclohexane–Benzene Mixtures

This study examines how phase state affects hydrogen abstraction and substitution reactions of tritium recoil atoms in benzene, cyclohexane, and their binary mixtures. Samples were neutron irradiated in gas, liquid, and solid phases, and the distribution of radioactivity among HT and labeled hydroca…

On the Directed Search for New Bifunctional Catalysts

This study examines the directed search for bifunctional catalysts for acylation reactions as models of enzymatic catalysis, focusing on compounds of the type R-COMH in which the hydrogen-bearing atom is nitrogen or sulfur rather than oxygen. The authors measured catalytic effects of thioacetic acid…

Change in the Rate and Direction of Methylcyclopentane Hydrogenolysis during High-Temperature Treatment of an Alumina-Platinum Catalyst with Hydrogen

This study examines how prolonged high-temperature hydrogen treatment of a 0.3% platinum on alumina catalyst affects the rate and selectivity of methylcyclopentane hydrogenolysis. Experiments at 350°C and 50 atm show that treatment with hydrogen at 550°C, intended to remove oxygen and water, sharply…

A New Determination of the Atomic and Electronic Structure of Dicyandiamide

The study refines the crystal and molecular structure of dicyandiamide and compares it with cyanamide to clarify changes in carbon, nitrogen bonding upon dimerization. Three-dimensional X-ray electron-density syntheses using 479 reflections were combined with self-consistent-field molecular-orbital …

On the Addition of Methylhydridosilacycloalkanes and Their Open-Chain Analogs to Ethylene

This study examines the catalytic addition of methylhydridosilicacycloalkanes and related open-chain hydridosilanes to ethylene as a route to 1,1-substituted silicacycloalkanes. Reactions were carried out at atmospheric pressure and 20 to 70 °C over platinized carbon, with reaction progress assessed…

Conductivity of an electrolytic $\mathrm{NaCl}$ solution in high-density water vapor

This paper reports measurements of the electrical conductivity of a one-molal NaCl solution in high-density water vapor under supercritical conditions. The authors used a platinum electrode cell in a high-pressure chamber and an alternating-current bridge, correcting for polarization by extrapolatin…

Synthesis of Polybenzoxazoles

This communication describes the synthesis of fully aromatic polybenzoxazoles intended as thermally stable polymers, using 3,3′-dioxybenzidine and aromatic dicarboxylic acid dichlorides. The authors prepare polyoxyamide intermediates at low temperature in polar aprotic solvents, then convert them by…

On the Nature of 1-Acylpyridinium Chlorides

This study examines the nature of addition products formed between acid chlorides and pyridine, addressing whether they are molecular complexes or true acylpyridinium salts. A series of 1-acylpyridinium chlorides was synthesized under rigorously anhydrous, low-temperature nitrogen conditions, and th…

On the Dependence of Adsorption Potentials at the Mercury/Electrolyte Interface on the Magnitude of Adsorption of Neutral Molecules

This paper examines how to choose the appropriate electrical variable, electrode potential or electrode charge, for describing adsorption of neutral organic molecules at the mercury, electrolyte interface. Using electrocapillary relations, the authors derive alternative adsorption criteria and show …

Reaction of Organomagnesium Compounds with 2,5-Dimethoxy-2,5-Dihydrofurans

This study examines the reactions of organomagnesium compounds with the heterocyclic acetals 2,5-dimethoxy-2,5-dihydrofuran and 2,5-dimethoxy-2,5-dihydrosilvan. Grignard reagents were reacted with these substrates under ether conditions, and the resulting products were characterized by physical cons…

Periodic Oxidation Reactions in the Liquid Phase

This paper reports a class of homogeneous liquid phase periodic oxidation reactions related to the Belousov reaction, in which bromate oxidizes compounds containing active methylene groups in strongly acidic solution with cerium or manganese ions as catalysts. Using optical absorption and electrode …

Hydrogenolysis of Cyclohexane to n-Hexane at Atmospheric Pressure

This study examines whether cyclohexane can undergo hydrogenolysis to open-chain hydrocarbons at atmospheric pressure, a reaction previously difficult to establish because dehydrogenation to benzene predominates on common catalysts such as platinized carbon. Using capillary gas chromatography, the a…