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 note studies approximation of unbounded twice continuously differentiable functions on the whole Euclidean plane by modified Landau polynomials and two forms of modified Bernstein polynomials. Under conditions on the scaling sequence and on the exponential growth of the function, it derives asy…
This study examines self-diffusion on the surface of polycrystalline silver, a process relevant to kinetic phenomena in solids and to the action of surface-active impurities. Using the layered specimen method with Ag110 tracer diffusion in silver foil packets annealed in hydrogen between 270 and 695…
This paper derives an equation for linear wave propagation in an ideally conducting compressible rotating plasma cylinder with arbitrary radial distributions of magnetic field, velocity, density, and temperature. Using the magnetohydrodynamic equations for stationary helical flows, the analysis redu…
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 paper extends the Poincaré, Andronov point transformation method to periodic solutions of functional differential equations with delay, allowing arbitrary relations between the delay length and the period. It formulates the shift operator on a space of initial functions, proves that periodic so…
The paper studies differentiability with respect to a fixed set of increments Q tending to zero, asking when Q-differentiability or bounded Q-derivative numbers on a set of positive measure imply asymptotic differentiability almost everywhere. It introduces a structural class D for such sets Q, char…
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 note examines the stability of an implicit finite difference scheme for a parabolic equation with variable diffusion coefficient, addressing the conjecture that stability for constant coefficients implies stability for variable coefficients. By analyzing the eigenvalue problem for a piecewise c…
This paper investigates the dark conductivity and photoconductivity of amorphous methyl chlorophyllide a layers prepared from chloroform solution, comparing their behavior with that of chlorophyll a and related organic semiconductors. Measurements in vacuum and oxygen atmospheres examine temperature…
The microwave spectrum of the molecule F2HC-CH2F is analyzed in relation to hindered internal rotation about the C-C bond and the symmetry between two folded conformations. The paper derives the expected classification of torsional-rotational states and predicts line doubling for transitions involvi…
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 paper investigates the occurrence and behavior of polyatomic silicon ions, Si2 to Si7 and occasionally Si8, in heavily doped single-crystal silicon analyzed by spark-source mass spectrography. By comparing silicon, silicon carbide, alloys, and dissolved salts, and by measuring arsenic- and boro…
The paper studies harmonic functions on the complex group GL(2), where harmonicity is defined by the real and imaginary parts of a bi-invariant second-order Laplace operator. It constructs such functions from functions on pairs of linear elements of the complex plane, identified with the homogeneous…
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…
The paper extends Glivenko’s theorem, and Kreisel’s related result for prenex predicate formulas, to a broader class of formulas in predicate calculus. It proves that if a formula contains no negative occurrences of the universal quantifier, then the negation of that formula is derivable in classica…
The paper studies semigroups defined by sets of identities and asks which identity systems force the corresponding variety to lie in specified classes of semigroups. It develops a consequence relation for identities, relates it to free semigroups in the class determined by a set of identities, and i…
This paper studies linear extremal problems for analytic functions with positive real part in finitely connected domains, subject to additional interpolation and inequality constraints on their real and imaginary parts. To treat these problems, it develops auxiliary results on compatibility and extr…
This note studies second order nonautonomous systems with small periodic perturbations of a rough autonomous planar system, using the period map associated with the perturbation. It proves persistence, for sufficiently small nonzero perturbation, of special structures corresponding to hyperbolic equ…
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 study examines how impurities affect the vibrational excitation relaxation time of oxygen molecules at high temperatures, addressing discrepancies between earlier measurements and the Landau Teller temperature dependence. Shock tube experiments were performed from about 1200 to 6600 K using car…
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,…
The paper examines the relationship between finite-decidable and finite-enumerable sets in automata theory, contrasting it with the classical algorithmic distinction between decidability and enumerability. It defines automata that decide input sets and enumerate output sets, introduces deciding comp…
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 paper addresses an apparent discrepancy between quantum and classical treatments of radiation damping of free electron oscillations in a weakly inhomogeneous magnetic field. For the nonrelativistic case, the authors derive perturbed Schrödinger wave functions, compute dipole radiation transitio…
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 presents a Fourier transform method for determining coefficients in mechanical cubature formulas that are exact on polynomials up to a prescribed degree at given nodes. It proves that exactness of the error functional on polynomials of degree less than m is equivalent to the Fourier trans…
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 investigates the germanium sulfur system, for which no phase diagram data were reported, using differential thermal analysis and powder and single-crystal X-ray diffraction. The authors prepare alloys across the composition range and establish a phase diagram showing liquid immiscibility …
This paper examines hydrodynamic oscillations and stability of weakly inhomogeneous low-pressure plasmas confined by magnetic fields, emphasizing limitations of approaches that yield coordinate-dependent spectra. Using a geometrical-optics asymptotic method for differential equations with slowly var…
This paper formulates a microscopic transition-state treatment of monomolecular reactions in crystal lattices, emphasizing how elementary decomposition in solids differs from the corresponding gas-phase process. The argument represents the reacting particle and its neighboring lattice block through …
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 examines how electron spin orientation affects the polarization and intensity of synchrotron radiation for an electron moving in a constant homogeneous magnetic field. Using solutions of the Dirac equation with additional conserved spin projection conditions, the authors derive radiation …
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 paper examines the short-wavelength “universal” instability of a weakly inhomogeneous rarefied plasma confined by a magnetic field when the ions are nonrelativistic and the electrons are relativistic. Using a kinetic dispersion equation with finite Larmor radius corrections for both species, th…
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…
The paper develops an averaged theory for the nonrelativistic motion of charged particles in a strong magnetic field when the transverse electric field is not assumed weak, so that the electric drift velocity may be comparable to the particle velocity. Using a Hamiltonian formulation with Poisson br…
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 note studies completeness for functional systems that model automata, focusing on precomplete closed classes under operations such as projection, renaming, substitution, parallel composition, and feedback. For boundedly deterministic operators, the paper defines preservation properties for clas…
This paper studies stability of generalized solutions to periodic Hamiltonian equations in a separable Hilbert space when the operator coefficient is unbounded. The coefficient is decomposed into a positive self-adjoint part and a subordinated perturbation, under conditions ensuring existence and un…
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…
