Recent Papers

Synthesis of Polymers from Nitriles of Aromatic and Aliphatic Acids by Polyrecombination Reaction

This study examines the synthesis of polymers and copolymers from aromatic and aliphatic acid nitriles through reactions initiated by tert-butyl peroxide. Benzonitrile, despite lacking mobile hydrogen atoms, gave polymeric products, and spectral and chromatographic evidence suggested preliminary rad…

On the kinetics of the interaction of acid chlorides with amines

This study examines the kinetics and possible stepwise mechanism of reactions between acid chlorides and secondary amines, motivated by their importance in polyamide synthesis and by limited prior data for fast aliphatic and heterocyclic amine acylations. Using very dilute solutions in heptane and a…

A New Method for Determining the Energy and Heats of Solvation of Individual Ions

A method is proposed for determining solvation energies and heats of individual ions by treating ion solvation as complex formation between solvent donor atoms and vacant ionic orbitals. The method uses the observed near linear dependence of cation and anion solvation energies on the reciprocal squa…

On the Low-Temperature Hexagonal Modification of $\mathrm{NaYF}_4$ with the Gagarinite Structure

The study addresses the unresolved structure of the low-temperature modification of NaYF4, prepared either by hydrothermal recrystallization of a stoichiometric melt or by hydrothermal synthesis from sodium fluoride and yttrium oxide. X-ray powder diffraction and chemical analysis showed that the pr…

Kinetics and Mechanism of the Alkaline Hydrolysis of Vinyl Esters

This study investigates the mechanism of alkaline hydrolysis of vinyl esters, focusing on whether bond cleavage occurs at the acyl oxygen, the vinyl oxygen, or by both pathways. Vinyl acetate, vinyl benzoate, and substituted vinyl benzoates labeled with oxygen-18 were hydrolyzed under homogeneous an…

Study of the Copolymerization Process of Butadiene with Isoprene in the Presence of Various Ionic-Type Catalysts

This study examines the copolymerization of butadiene with isoprene in the presence of anionic, cationic, and complex organometallic catalysts, using carbon-14 labeled butadiene to determine copolymer composition and infrared spectroscopy to analyze polymer microstructure. The copolymerization const…

Determination of the Degree of Isotacticity of Polypropylene from Its Infrared Spectra

This paper proposes an infrared spectroscopic method for determining the degree of isotacticity of polypropylene, distinguishing tacticity-sensitive absorption bands from crystallinity bands that had previously been used as indirect measures. The authors argue that the 976 cm^-1 band, normalized to …

Determination of Crystal Structures by Minimization of the $R$-factor

This paper examines the use of direct minimization of the crystallographic discrepancy factor for obtaining preliminary molecular crystal structures from X-ray diffraction data. The authors replace the full coordinate-dependent R factor with a parametrized function based on rigid-body molecular para…

On the Stability of Complex Compounds of Transition Metals

This paper examines how instability constants of transition-metal complexes vary with the nature of the metal atom, focusing on fourth-period elements and the applicability of ligand-field stabilization concepts. Using published tables of stability data, it compares complexes of Ca, Mn(II), and Zn f…

On the “Anomalous” Effect of Substituents in $S_E$ 2 Reactions

This paper examines the anomalous influence of substituents in electrophilic bimolecular substitution reactions of ethyl alpha-bromomercuriarylacetic acid esters, motivated by earlier symmetrization results that contradicted the usual expectations for an SE2 mechanism. The authors study the iodine r…

Synthesis and Properties of Hexachlorocyclohexylchlorosilanes

The study investigates additive and substitution chlorination of aromatic chlorosilanes, focusing on phenyltrichlorosilane and phenylmethyldichlorosilane. Chlorination experiments under varying temperature and irradiation conditions show that low temperatures favor addition of chlorine to the aromat…

On a Rigorous Method for Calculating the Activation Energy of Electrochemical Reactions

The paper critiques the common temperature kinetic use of an Arrhenius plot of total current to obtain an “effective” activation energy for electrochemical reactions, arguing that this procedure is generally invalid for kinetically reversible electrode processes and in regions affected by diffusion.…

Two-quantum photochemical reaction. Photolysis of a frozen solution of diphenylamine in ethyl alcohol

The study examines the mechanism of radical formation during photolysis of frozen diphenylamine solutions in ethanol at 77 K, with particular attention to whether the reaction proceeds by a two-quantum process. Using controlled irradiation intensities and electron paramagnetic resonance measurements…

The mechanism of carbon monoxide adsorption and conversion in the liquid phase

This study examines the mechanism of carbon monoxide adsorption and conversion in aqueous acid solutions on platinized platinum electrodes. Using electrochemical charge curves and measurements of potential change during CO saturation, the authors compare the effects of temperature, saturation time, …

On the Spontaneous and Induced Decay of Doubly Charged Ions

This study examines spontaneous and collision-induced dissociation of doubly charged ethylene ions, including C2H4 2+, C2H3 2+, and C2H2 2+, produced by 130 eV electron impact and analyzed with a double mass spectrometer. By measuring secondary ion intensities as functions of ionizing electron energ…

Structure of adducts of trifluoronitrosomethane with unsaturated compounds and the mechanism of their formation

This paper examines the reactions of trifluoronitrosomethane with fluoroolefins, styrenes, acrylates, and vinyl acetate, with emphasis on the structure of adducts and the mechanism of their formation. Using electron paramagnetic resonance together with chemical transformations, infrared spectra, flu…

On the rearrangement of $\alpha$-hydroxyphosphinic and $\alpha$-hydroxythiophosphinic esters into phosphinates and thiophosphates

This paper examines base-catalyzed rearrangements and decompositions of alpha-hydroxyphosphinic, alpha-hydroxythiophosphinic, and related phosphinous ester derivatives, focusing on how substituents and phosphorus-containing groups determine the reaction pathway. Using reactions of carbonyl compounds…

Technical Synthesis of Carbonyl Monomers Based on the Mannich Reaction

This paper examines the use of the Mannich reaction as a technical route to carbonyl monomers, especially alpha, beta-unsaturated aldehydes and ketones, addressing the previously reported difficulty of irreproducibility. The authors study aminomethylation of aldehydes and ketones with formaldehyde a…

On the Use of Luminescent Reagents in the Kinetic Method of Analysis

This paper proposes the use of luminescent reagents in kinetic analytical methods for cations with unfilled electron shells, where direct fluorescence complexation is often limited by quenching. Two catalytic luminescence reactions are described: oxidation of a fluorescent stilbene derivative by hyd…

Study of the Polarization Characteristics of Circulating Powder Electrodes

This paper examines association phenomena in solutions of ortho-regular phenol-formaldehyde novolac resins, focusing on the role of intra- and intermolecular hydrogen bonding in their structure. Infrared spectra of resin solutions and model dioxydiphenylmethanes in carbon tetrachloride were studied …

Potential functions of molecules in the homologous series $(\mathrm{CH}_3)_n\mathrm{SiF}_{4-n}$ ( $n=1-4$ )

The paper examines the potential functions and vibrational properties of the methylfluorosilane series (CH3)nSiF4-n, with n from 1 to 4. Using established methods for molecular vibration calculations, it determines force constants, interaction coefficients, normal vibration frequencies and forms, an…

X-ray diffraction and spectral study of complex compounds of monovalent copper rhodanide with thiourea and pyridine

This study examines the coordination and composition of newly prepared complex compounds of cuprous thiocyanate with thiourea and pyridine, using X-ray crystallographic measurements and infrared spectroscopy. Unit-cell parameters, densities, and molecular-weight estimates from X-ray data support the…

On the Entropy of Systems Containing Difficult-to-Distinguish Components

This paper examines the entropy of mixing for ideal gases whose components are not perfectly distinguishable, treating entropy as a measure of missing information about molecular identity. Using an information theoretic recognition model, the authors derive an expression in which the entropy of mixi…

On the Periodic Regularity of Isotopic Exchange in Diatomic Molecules

This paper examines the periodic variation of isotope exchange beta factors in diatomic molecules, focusing on hydrides and extending the discussion to other monovalent elements. Using statistical expressions for beta factors, vibrational frequency relations, and the empirical Guggenheimer formula, …

Surface coverage by an organic substance at the potentials of maxima on differential capacitance curves

The paper analyzes how the surface coverage of an organic adsorbate at maxima of differential capacitance curves depends on electrode potential and concentration within Frumkin adsorption theory. Assuming constant double-layer capacitances and a constant attraction parameter, the authors derive cond…

On the Thermomechanical Characteristic of the Molecular Weight of Linear Polymers: The Example of Natural Rubber

This paper examines the use of thermomechanical curves to estimate the molecular weight of linear polymers, focusing on natural rubber. Because conventional determination of the flow temperature is difficult and may introduce large errors, the authors propose using the more reproducible temperature …

Interpretation of Resonance Absorption of $\gamma$ Quanta by Some Complex Iron Compounds Taking into Account Bond Covalency and Inductive Effects

This paper interprets differences in Mössbauer resonance absorption spectra for three low-spin iron(II) complexes with related thiosemicarbazone diacetyloxime ligands whose nearest coordination environment is formally the same. Using a qualitative molecular-orbital treatment that includes metal-liga…

Study of the Interaction Between Oxides of Rare-Earth and Alkaline-Earth Metals

This study examines how rare-earth oxide amphotericity and ionic size affect reactions with alkaline-earth oxides, focusing on strontium oxide with La, Sm, Dy, and Yb oxides and selected reactions involving CaO and BaO. Mixtures were calcined in air and analyzed by X-ray phase methods to identify re…

On the Possibility of Conducting Catalytic Dehydrogenation in a Chromatographic Mode

This study examines whether catalytic dehydrogenation of n-butylenes to divinyl can be carried out in a pulse chromatographic regime, where reaction components are separated as zones while passing through an alumina-chromia catalyst. Using gas chromatographic experiments with mixtures and isolated b…

Purification of Indium from Tin and Lead Impurities by Zone Melting of Its Chloride

This study examines the purification of indium from tin and lead impurities by zone melting a eutectic mixture of indium chloride and sodium chloride, a route intended to overcome the poor impurity separation obtained during zone melting of metallic indium. Experiments were performed in sealed glass…

Luminescence of a uranyl complex with phthalocyanine

This study examines the luminescence of a synthesized uranyl phthalocyanine complex and the influence of the uranyl ion on the phthalocyanine chromophore. Infrared, electronic absorption, and luminescence spectra in several solvents and at different temperatures are compared with spectra of metal-fr…

Ethylene Polymerization on a Chlorinated Mixture of Titanium and Aluminum Metals

This paper investigates heterogeneous catalysts for low pressure ethylene polymerization prepared by treating mixtures of metallic aluminum and titanium with chlorine or dry hydrogen chloride in benzene. Experiments varying metal ratio, chlorination conditions, temperature, pressure, and Cl/Al ratio…

On the Polymerization of Isoprene in the Presence of Complexes of Titanium Tetrachloride, Triethylaluminum, and Amines

This study examines how nitrogen-containing compounds affect the titanium tetrachloride, triethylaluminum catalytic system used for isoprene polymerization. Isoprene was polymerized in heptane under varied orders of addition of phenyl-beta-naphthylamine, and selected experiments were also performed …

Effect of Alternating Current Frequency on the Passivation Process of Titanium

This study examines how the frequency and voltage of sinusoidal alternating current affect corrosion and passivation of titanium in 10 N sulfuric acid. Using VT-1 sheet titanium electrodes, the authors measured anodic and cathodic potential amplitudes, phase shifts, Faradaic and capacitive current c…

Interaction of Metallic Lanthanum with Its Trichloride Melt and the Equilibrium Constant of the Reaction $2\mathrm{LaCl}_3(\text{l})+\mathrm{La}(\text{l})\rightleftarrows3\mathrm{LaCl}_2(\text{l})$

The study examines the interaction of metallic lanthanum with molten lanthanum trichloride and the equilibrium of the reaction forming lanthanum dichloride. Direct chemical analysis of equilibrated melts, emf measurements of concentration cells, and thermal analysis of the La, LaCl3 system were used…

In our article: V. E. Plyushchev, V. M. Amosov, M. B. Varfolomeev, “Synthesis and Some Properties of the Lower Crystalline Hydrates of the Perrhenates of Yttrium, Lanthanum, and Lanthanoids,” published in *DAN*, vol. 150, No. 1, 1963, in Table 1 (p. 107), we erroneously placed values of the refractive indices relating not to lower but to other crystalline hydrates of perrhenates, whose properties will be published in another communication.

Salts of diphenyl- $o,o'$ -diphenyleneammonium

This paper reports the preparation and characterization of salts of diphenyl-o,o′-diphenylenammonium, presented as the first representatives of fully aromatic tetraarylammonium compounds. The compounds were obtained by diazotization of o-amino-o′-diphenylaminodiphenyl in acetic acid, followed by ani…

Syntheses Based on Organolithium Compounds of the Furan Series. Alkyl-( $\alpha$ -furyl) Sulfides and Some of Their Transformations

This paper describes syntheses of alkyl furyl sulfides using organolithium compounds of the furan series, emphasizing a route that avoids preliminary halogenation required for organomagnesium intermediates. Furyl lithium or substituted furyl lithium compounds are treated with sulfur followed by alky…

Effect of Bromine on the Optical Properties of Purine and Pyrimidine Bases

This study examines how bromination alters the ultraviolet absorption spectra of purine and pyrimidine bases and what these changes indicate about the reaction mechanism. Using acidic bromine water, spectrophotometry, kinetic observations, and paper chromatography, the authors compare uracil, cytosi…

Study of IR Spectra During the Polymorphic Transformation of Tristearin

This study examines changes in infrared absorption spectra during polymorphic transformation of tristearin from a rapidly cooled glassy state to crystalline alpha and beta forms. Thin films were prepared between KBr plates and recorded with thermostatic control in the 3000 to 700 cm−1 region after q…

Preparation of halogen anhydrides of $\alpha$ , $\beta$ -alkenylphosphonic acids

The study examines reactions of vinyl and substituted vinyl phosphites with bromine and phosphorus pentachloride as routes to halogen anhydrides of alpha,beta-alkenylphosphoric acids. Bromination of phosphites containing only alkenyl groups or phenyl and alkenyl groups gives crystalline quasiphospho…

On the Ionization of Oxygen on Palladium

This study examines oxygen ionization on palladium electrodes in concentrated alkaline solution and relates the electrode activity to the properties of surface oxygen compounds. Polarographic measurements on palladium, platinum, and silver, together with cathodic charging curves after anodic oxide f…

Autooxidation of $n$-dicyclohexylbenzene

This paper examines the liquid-phase autooxidation of p-dicyclohexylbenzene with oxygen in the presence of manganese resinate, with and without alkaline additives, as a model for studying dialkylbenzene oxidation. The authors follow oxygen uptake and iodometric hydroperoxide formation at different t…

On the Non-Coplanarity of Benzalaniline and Its Derivatives

This paper examines the preferred conformation of benzalaniline and substituted aromatic anils, challenging the commonly assumed planar structure. Using a semiempirical LCAO molecular orbital calculation in the Hückel approximation, the authors compare planar, orthogonal, and intermediate arrangemen…

Preparation and Study of the Catalytic Properties of High-Molecular-Weight Polystyrenesulfonic Acid

This study compares the catalytic behavior of high-molecular-weight polystyrenesulfonic acid with that of the low-molecular-weight model acid toluenesulfonic acid in the hydrolysis of ethyl acetate in aqueous solution. Polystyrenesulfonic acid was prepared by photopolymerization, and hydrolysis kine…

Dependence of the yield of molecular products of water radiolysis on the concentration of radical acceptors

The paper addresses the experimentally observed decrease in molecular hydrogen and hydrogen peroxide yields during water radiolysis as the concentration of radical acceptors increases. Using the spur model of radiolysis, it treats the diffusion and recombination of H and OH radicals in an isolated s…

Precipitation Isotherm

This paper derives a generalized precipitation isotherm needed for the theory of precipitation chromatography and dynamic precipitation sorption. Starting from mass balance, stoichiometric relations, and the solubility product rule with activity coefficients, it obtains a functional relation between…

Radical isomerization of acetophenone diphenyl mercaptol

This study examines the radical isomerization of acetophenone diphenylmercaptol under heating in chlorobenzene, chiefly in the presence of tert-butyl peroxide, to clarify how mercaptol structure affects rearrangement. The reaction gave 1,2-bis(phenylthio)ethylbenzene, diphenyl disulfide, and alpha-p…

Investigation of the niobium–beryllium system

This study investigates the poorly characterized niobium-beryllium system using thermodiffusion alloying, metallography, X-ray diffraction, local X-ray spectral analysis, microhardness measurements, thermal analysis, and heat of formation measurements. Diffusion experiments at 900 to 1300°C and stud…

Spectra of EDA complexes of 4-nitrodiphenylalkanes containing a donor group in the other ring. EPR effect

This study examines the origin of the long wavelength absorption and coloration of 4-nitrodiphenylalkanes bearing amino or dialkylamino donor groups in the second ring. Absorption spectra in nitrobenzene, aniline, dimethylaniline, and diethylaniline are compared at different concentrations with spec…