SovietRxiv · Open Access in English
Rediscovering the Soviet scientific archive, in English
25357 full-text translations 14926 English PDFs 22539 abstracts
Showing 50 of 25357 papers
This paper investigates whether a monoenergetic, well collimated proton beam can be used as a diagnostic of turbulent collective oscillations in a plasma. A 50 keV proton beam was passed through the turbulent plasma of a high voltage direct discharge, and time resolved beam broadening was recorded i…
This paper proposes a variant of the method of successive approximations for numerical integration of two-dimensional incompressible Prandtl boundary-layer equations with an arbitrary pressure gradient, assuming that a solution exists. The method integrates the momentum equation with respect to the …
This paper reports the synthesis and microscopic characterization of NiAsS formed by nickel diffusion into As-S glass at 450 to 600 degrees C and 30 to 70 kbar. Optical and X-ray analyses identify the product with the gersdorffite structure, while polished sections reveal that the crystallites are n…
This paper studies interpolation of pseudoanalytic functions, a class of generalized analytic functions satisfying a homogeneous Vekua equation. Using Bers’ integration process and the Cauchy formula for pseudoanalytic functions, it derives analogues of the Lagrange-Hermite and Abel-Goncharov interp…
This paper proves uniqueness for a Tricomi boundary value problem for a class of nonlinear mixed type equations of the form \(y^m u_{xx}+u_{yy}=f(x,y,u)\), where the equation is elliptic in the upper half plane, hyperbolic in the lower half plane, and degenerates on the line \(y=0\). Under continuit…
This paper examines the remote determination of surface soil characteristics from microwave thermal radio emission. Using a model for the radio-brightness temperature of a semi-infinite medium and an empirical approximation of the soil temperature profile, it derives relations between measured brigh…
The paper presents an iterative method for constructing cubic and polycubic spline functions by formulating spline interpolation as a boundary value problem for fourth order differential equations with coefficients vanishing at interpolation nodes. After finite difference discretization on a refined…
This paper investigates the orientation dependence of characteristic X-ray spectral line parameters for vanadium atoms in a single crystal of vanadium pentoxide. Using X-ray spectrometry with the crystal as a rotatable anode, the authors measured the spectral position, maximum intensity, half-width,…
The paper presents a method for solving systems of linear algebraic equations with symmetric positive definite matrices by interpreting them as Ritz systems for a functional equation in an energy space. It derives an algorithm based on orthonormalizing a corresponding system of vectors, showing that…
This paper examines stresses arising during axisymmetric buckling of thin spherical shell segments, focusing on an experimental check of a previously derived formula relating stress to shell thickness, local bending geometry, and material properties. Instead of measuring stress directly, the study m…
This paper studies qualitative stability and instability in the large for a class of discrete amplitude-pulse automatic control systems consisting of a linear difference equation coupled to nonlinear modulators with memory. Using quadratic forms, transfer-function conditions on the unit circle, and …
This note studies when a sequence of approximate extremal minimization problems converges to a given original problem, both in the value of the functional and in the construction of minimizing elements. It formulates necessary and sufficient conditions using comparison mappings between the approxima…
This study examines the photochemical decomposition of lead and silver azides, including coprecipitated systems containing silver, copper, or lead additives. Decomposition kinetics were measured by nitrogen evolution under irradiation in intrinsic and impurity absorption regions, with attention to i…
This paper examines whether Fitzgerald’s relation between lattice binding energy and sound velocity can be extended from monatomic crystals to alkali halide crystals and related substitutional solid solutions. Using elastic constants and isotropic longitudinal and transverse sound velocities, the au…
This paper investigates the elastic properties of pressed polycrystalline solid solutions in the KCl, KBr and KBr, KI systems, with emphasis on the effects of porosity and composition. Longitudinal and transverse ultrasonic wave velocities were measured by a pulse method, and Young’s and shear modul…
This paper addresses the assessment of explosion hazards in multicomponent dynamic gas systems, focusing on the hydrogen, oxygen, and nitrogen system in closed volumes with continuously supplied components. Using published concentration limit data and recalculating them in terms of absolute nitrogen…
This study examines how reduced total pressure affects the lower concentration flammability limit of hydrogen in hydrogen, oxygen and hydrogen, air mixtures, especially for upward flame propagation relevant to explosion safety in closed volumes. Experiments were conducted in a vertical steel explosi…
This paper examines the lack of general design principles for electrical spark-discharge ignition systems used in fuel combustion and explosion-hazard testing of vapor-gas mixtures. Drawing on prior work on flame-kernel formation and ignition inertia, it argues that ignition efficiency should be opt…
The paper addresses how to assess the explosibility of complex atmospheres in enclosed volumes used in aviation, submarine, and similar technologies, where initially safe gas mixtures may become hazardous through combustible products, material decomposition, radiation, temperature effects, or human …
This study examines chemical processes that occur when irradiated or additively colored alkali halide crystals dissolve in aqueous media, with emphasis on electron and hole radiolysis products. Using measurements of hydrogen, halogen products, nitrite formation, and solvent effects in water, nitrate…
This paper investigates the chemical forms and determination of localized hole radiolysis products in gamma irradiated alkali halide crystals, including sodium chloride, potassium chloride, potassium bromide, and potassium iodide. Optical spectroscopy and dissolution experiments with selected indica…
This paper describes an electronic device for visualizing local inhomogeneities in radiation fields as a three-dimensional axonometric image on a cathode-ray tube. The system uses an X-ray vidicon as the radiation detector, two sweep generators, video amplification, synchronization and blanking circ…
This paper proposes a probabilistic geometric method for estimating statistical characteristics of the internal structure of composite materials whose dispersed particles have random sizes and arrangements. The model represents the structure as a limiting dense packing of unequal spheres, decomposed…
This paper proposes two digital mathematical models for representing fluid structure as random packings of equal rigid spheres in a bounded three-dimensional volume. The first model describes weak molecular bonding with a uniform spatial distribution, while the second introduces additional geometric…
This paper examines the statistical characterization of random structures without long-range order, using digital mathematical models of single-atom fluids represented as bounded random packings of nonintersecting spheres. Algorithms implemented on an M-20 computer compute radial functions and pair …
This paper analyzes how local inhomogeneities in the radiation field behind a moving object are converted into electrical signals by a scintillation detector in radiometric defectoscopy. Treating the detector and collimator as a linear filter, the authors derive response and spectral expressions sho…
This paper examines how to estimate the limiting output bandwidth of a detector scanning through an inhomogeneous radiation field, where the signal spectrum depends on collimator geometry, detector speed, field structure, and sensitivity distribution. The authors formulate the detector response as a…
This paper analyzes the detection of localized inclusions in heterogeneous media by radiation transmission methods when random distributed inhomogeneities produce background flux fluctuations. It models transmitted intensity in terms of attenuation coefficients, filling density, fluctuation variance…
This paper describes a computational method for determining characteristics of finite bremsstrahlung beams after passage through thick absorber layers, especially quantities depending on the on-axis spectral intensity distribution. The authors present an M-20 computer program combining numerical cal…
This paper addresses the problem of obtaining a visual, dynamic representation of spatial inhomogeneities in radiation fields while retaining the quantitative advantages of point measurements. It formulates an analytic basis for transforming detector coordinates and measured field intensity into an …
This paper develops an analog-computer kinetic model for the initial photolysis of heavy metal azides, focusing on lead, silver, and thallium azides, where electronic stages are thought to dominate decomposition. A system of nonlinear differential equations is formulated for exciton formation, ioniz…
This paper examines separation in binary hydrogen and nitrogen gas mixtures under gravity, inertial forces, and thermal diffusion. Using thermodynamic equilibrium expressions for external fields and Chapman and Enskog thermal diffusion theory, the authors estimate concentration changes for gravitati…
This paper examines determination of kinetic parameters for first-order unimolecular reactions under nonisothermal conditions, with particular attention to linear heating. The authors integrate the rate equation with an Arrhenius rate constant, present exact and approximate expressions involving the…
This paper examines the intraparticle diffusion kinetics of carbon dioxide adsorption on industrial NaX zeolites, motivated by applications in air purification. Kinetic uptake curves were measured with an automated McBain balance for pure carbon dioxide and carbon dioxide, nitrogen mixtures at 25 de…
This paper examines the selection of ignition methods for determining explosion hazards in combustible gas atmospheres, especially concentration limits and minimum ignition energies under normal and reduced pressures. It compares heated surfaces and other industrially plausible ignition sources with…
This paper examines the microscopic and macroscopic factors governing electrical breakdown in pressed polycrystalline lead azide, with particular attention to pore microdischarges, edge discharges, and electron avalanche processes. A simple layered porous dielectric model is developed to relate brea…
This study examines electrical breakdown and detonation initiation in thallium azide and copper(II) azide under short voltage pulses of about 10 to the minus 7 seconds. Using pressed tablet samples in a sphere to plane electrode geometry, the authors vary electrode material, polarity, and temperatur…
This study examines how the distribution of divalent copper impurity affects the thermal decomposition of silver azide and lead azide. Polycrystalline and single crystal samples with copper additions were prepared and compared using thermal decomposition measurements, differential analysis, weight l…
A method is proposed for determining the total heat required for high-temperature gasification of organic fuels, a quantity important for hybrid and solid-fuel combustion systems but difficult to measure by existing thermographic or block-calorimeter techniques. The approach treats small organic add…
This study examines how the chemical nature of solid fuels affects the combustion rate of condensed mixtures using ammonium perchlorate as a common oxidizer. Powdered mixtures of ammonium perchlorate with selected polymers and corresponding monomers were burned in a constant-pressure nitrogen bomb, …
This paper investigates how transition metal oxide catalysts affect combustion of condensed ammonium perchlorate based mixtures, focusing on near surface temperature as a diagnostic of reaction mechanisms. A model mixture of ammonium perchlorate and epoxy resin was burned at reduced pressures, and n…
This study examines the linear pyrolysis of pressed ammonium perchlorate pellets containing 2 percent by weight of copper oxide, manganese dioxide, or iron oxide on a continuously heated plate. Pyrolysis and burning rates were measured over a plate temperature range of about 300 to 800 degrees Celsi…
The study examines the thermal decomposition of guanidinium perchlorate, focusing on discrepancies in earlier reports concerning gaseous products and the initial decomposition step. Decomposition products were analyzed by mass spectrometry under two sets of conditions: in a reaction vessel connected…
This paper examines how heterogeneous additives catalyze the thermal decomposition of ammonium perchlorate, with particular attention to whether their action involves the rate-limiting decomposition of perchloric acid formed during thermolysis. Using mass spectrometric analysis of ammonium perchlora…
The study investigates the thermal decomposition of ammonium chlorate, addressing disagreements in earlier work about product composition and reaction mechanism. Ammonium chlorate was prepared by exchange synthesis, decomposed at 80 to 95°C, and examined by kinetic weight-loss measurements, chemical…
This paper examines how heterophase solid additives influence the thermal decomposition of heavy metal azides, especially silver, lead, and thallium azides. Using kinetic measurements, microscopy, differential thermal analysis, thermogravimetry, and qualitative chemical analysis across more than 120…
This review examines how the type, formation mechanism, and impurity distribution of mixed crystals affect interpretations of their thermal decomposition and stability. It systematizes classifications of true isomorphous, anomalous, new-kind, and internally adsorbed mixed crystals, describes princip…
This paper describes the design and operation of a spark generator intended to produce approximately rectangular ignition pulses for studies of spark-discharge ignition, minimum ignition energies, and concentration limits of explosive vapor-gas mixtures. The authors present an electrical circuit usi…
A combined experimental setup is described for investigating radiation-induced and thermally stimulated processes in solid compounds under high vacuum. The apparatus permits measurements on a single sample of X-ray luminescence, thermoluminescence, spectral ranges from 200 to 800 nm using light filt…
This paper describes the construction of an experimental installation coupling an EPA-2 radiospectrometer with an ESG-2.5 electrostatic accelerator for electron-beam irradiation of samples during radiospectroscopic measurements. The authors outline the required modifications to the spectrometer, res…
