SovietRxiv · Open Access in English
Rediscovering the Soviet scientific archive, in English
25456 full-text translations 14926 English PDFs 22540 abstracts
Showing 50 of 25456 papers
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…
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…
The paper studies equivalent transformations of logical networks obtained by replacing subnetworks with equivalent subnetworks, focusing on networks built from functional elements and delay elements. Extending known results for networks without delays, it proves that for every fixed number k there i…
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…
The paper studies boundary value problems for linear uniformly elliptic second order equations in three-dimensional exterior domains, with coefficients and right-hand sides controlled by weighted Hölder norms defined through Dini functions. It establishes Schauder-type a priori estimates for the Dir…
This paper studies homotopy properties of groups of diffeomorphisms of spheres and disks, especially the quotients arising from the restriction fibration from diffeomorphisms of the disk to those of its boundary sphere. Using framed manifolds, Morse surgery, and relations between the Whitehead homom…
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…
This paper studies when the transition function of a machine, in the sense of Ginzburg, can be represented by multiplication in an associated semigroup. It introduces right and left machines, p-machines with semigroup state sets, and m-semigroups that generate machines, then proves embedding results…
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…
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…
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 …
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…
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…
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…
The paper introduces separating finite partitions for identifiable families of probability measures and relates them to the construction of simple consistent and asymptotically efficient parameter estimates. It defines the minimal size of such a partition and shows existence or bounds for several cl…
This paper investigates the complex valence-band and exciton structure of hexagonal cadmium selenide crystals, focusing on how crystal-field and spin-orbit interactions split the upper valence band. Using high-dispersion absorption and reflection spectroscopy over broad spectral and temperature rang…
This paper derives a kinetic equation for a nonideal Fermi system with a general nonlocal pair interaction, using Bogolyubov’s generating functional method for quantum statistics and a perturbation expansion in the interaction strength. The authors introduce a two-particle correlation operator, impo…
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…
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.…
This paper studies error estimation for numerical solutions of nonlinear integral equations when only values at quadrature nodes are used. The equation is reduced by a quadrature formula to a finite system whose residual at the computed vector, together with the quadrature error, is used to bound th…
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…
This note extends the Schiffer and Goluzin variational method to several classes of analytic functions in the unit disk, including bounded nonzero functions, functions with positive real part, typically real functions, spirally starlike and spirally convex functions, and functions of bounded rotatio…
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, …
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…
The paper studies conditions under which a mapping from a subring of an ordered Boolean ring into a complete separated topological Abelian group can be extended to the closure of that subring. It formulates three compatibility and continuity conditions involving prescribed families of indexed mappin…
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…
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…
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…
The paper studies the existence of regularly varying similar tests for a generalized Behrens-Fisher problem involving two independent normal samples with linear mean structures and unknown variances. It formulates invariance and sufficiency conditions extending Wald-type axioms, reduces admissible t…
This paper studies Radon integrals whose integrands and measures both depend on a parameter, focusing on conditions under which the integral converges uniformly with respect to that parameter, a property used in continuity questions. It proves a necessary and sufficient criterion analogous to the Va…
This paper studies two boundary value problems for the mixed type Lavrent’ev, Bitsadze equation in a domain whose upper part is elliptic and lower part is bounded by characteristics. For a generalized problem of type T1, the solution is represented in the hyperbolic part by characteristic data and i…
The paper develops an asymptotic method for eigenvalue problems arising in the linear stability theory of an inhomogeneous rarefied plasma in a strong magnetic field, where the governing operator is integro-differential and contains a small parameter such as the Larmor radius. Using a WKB-type repre…
This paper studies a stability form of Liouville’s theorem for conformal mappings in n-dimensional Euclidean space within Sobolev classes. For topological mappings of the unit ball into itself whose normalized energy to Jacobian ratio is at most 1 plus a small epsilon, it proves the existence of a M…
The paper studies when a continuous direct integral of factor representations of a second countable locally compact group is itself a factor representation, motivated by the unclear structure of factor representations of types II and III. It introduces a measure-relative notion of weak equivalence, …
This paper develops a kinetic description of weakly turbulent collisionless plasma that supplements quasilinear theory by including nonlinear wave, wave interactions of second order. Starting from dynamical equations for slowly varying wave amplitudes and an expansion of the particle distribution fu…
The paper formulates a linear programming model for optimizing production assortment and distribution of heterogeneous products among production sites, consumers, and transport modes under resource, transport capacity, and demand constraints. It derives optimality conditions by representing feasible…
The paper studies Chebyshev subspaces of Banach spaces and introduces almost Chebyshev subspaces, for which uniqueness of best approximation may fail only on a first category set. It proves nonexistence results for Chebyshev and almost Chebyshev subspaces in certain nonseparable or nonreflexive sett…
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…
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 …
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…
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…
This paper studies inequalities and sign properties for sums of trigonometric sine and cosine series whose coefficients satisfy weakened monotonicity or convexity conditions. Using decomposition lemmas for sequences of bounded variation and finite differences, it extends Fejér type positivity result…
This paper develops an approximate frequency method for determining complex steady-state motions in nonlinear impulse automatic systems when the motion can be represented by a single predominant harmonic. Extending harmonic-balance ideas, it defines an equivalent complex gain for the nonlinear impul…
This note estimates the growth of the epsilon entropy of compact classes of bounded continuous functions on a parallelepiped, defined by upper bounds on finite differences of arbitrary orders in each coordinate. Using a multidimensional polynomial approximation lemma extending Whitney’s result, the …
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…
This paper studies general boundary value problems for elliptic systems in the sense of Douglis and Nirenberg, allowing operators of different orders in different components. It formulates a complementing condition for the principal boundary operators, analogous to the Agmon, Douglis, and Nirenberg …
The paper studies the problem of choosing m vertices of the unit n-dimensional cube so as to minimize the sum of reciprocal Hamming distances between all chosen pairs, a model motivated by arrangements of equal charges and by optimal error-correcting codes. It focuses on the case m equals half the n…
The paper studies scalar and general linear differential systems with bounded coefficients and a small retarded argument, focusing on the long term relation between arbitrary solutions and special delay free approximating solutions constructed by a small parameter method. For the equation x'(t) = p(…
