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 paper studies the computation of the smallest eigenvalue of a real symmetric positive integral-equation kernel using traces of iterated kernels. It reformulates the Fredholm determinant trace expansion through the series for the ratio of the determinant to its derivative, derives positivity and…
This paper solves the hydromechanical problem of the motion of a flat plate of infinite span near the free surface of an ideal weightless liquid. Using Kirchhoff’s method, it constructs a parametric representation of the flow for cases in which the upper surface of the plate is partly or completely …
This paper studies conjugacy and intersections among several classes of triangular sequence transformations, especially Hausdorff, Voronoi, Riesz, Cesàro, Euler, and analytic transformations. It formulates criteria connecting conjugate Hausdorff transformations through delta transformations, absolut…
This paper gives an exact closed form solution for Kirchhoff separated flow of an ideal incompressible fluid past a two parameter family of symmetric curves in a channel bounded by two parallel walls. The author defines the family of curves, derives expressions for their curvature, arc length, endpo…
This paper studies linear and nonlinear evolution equations in Hilbert space of the form dx/dt plus A(t)x equals f(t), where A(t) is an unbounded self-adjoint operator depending on time. Under differentiability and boundedness assumptions on fractional powers of A(t), it refines the construction of …
This study examines chemical changes in alpha-cellulose isolated from pine wood ranging from young shoots to fossil material of interglacial age. Cellulose samples were prepared by the sulfate method, purified with alkali, and analyzed by elemental composition, nitration and acetylation reactions, d…
This paper examines crystallization in statistical physics using Bogolyubov’s method of distribution and correlation functionals, aiming to connect the structure of a system with its thermodynamic functions. It derives an equation for the one-particle distribution function, formulates a free-energy …
This paper develops a priori estimates for analytic and generalized solutions of the Monge-Ampère equation rt minus s squared equals a positive function of the independent variables, the solution, and its first derivatives. Extending estimates of Bernstein and Pogorelov, it derives bounds for the so…
The study examines the acid-catalyzed decarbonylation of benzoylformic acid in concentrated sulfuric acid, using spectrophotometric monitoring at 400 nm to relate reaction rates to acid-dependent molecular forms. Measurements over 85.46 to 99.94 percent sulfuric acid show first-order decomposition w…
This paper studies the gas motion produced by a point explosion in a homogeneous gas when the initial ambient pressure can no longer be neglected. It develops an approximate solution by expanding the one-dimensional unsteady gas-dynamic equations in powers of a parameter depending on the ratio of sp…
The study investigates the kinetics of dehydrogenation of ethyl alcohol, isopropyl alcohol, benzyl alcohol, and cyclohexanol over a precipitated copper catalyst in a flow apparatus. Relative adsorption coefficients for reaction products and hydrogen were determined by a reaction kinetic displacement…
This paper examines the reactivity of isolable intermediate products of the Arbuzov rearrangement with secondary amines, by analogy with their known reactions with alcohols. Several aryl phosphite alkyl iodide complexes were prepared and treated with diethylamine or dimethylamine, with quantitative …
This note establishes an integral form of the maximum principle for solutions of strongly elliptic second-order systems, since such systems need not satisfy the usual pointwise maximum principle. For a vector solution in a cylinder with zero lateral boundary values, the argument studies the time dep…
This paper studies a mixed boundary and Cauchy problem for the hyperbolic equation \(\psi_{\sigma\sigma}-K(\sigma)\psi_{\theta\theta}=0\), with zero boundary values on two parallel lines after reduction and Cauchy data prescribed on a noncharacteristic curve. The problem is transformed to a strip an…
This note studies a class of operator equations in a Hilbert space whose coefficients depend nonlinearly on a complex parameter and have simple real poles. Under compactness, self-adjointness, bounded trace and norm, and sign assumptions on the finite-dimensional pole terms, the paper develops a spe…
This note studies the perturbation of unbounded self-adjoint linear operators \(H_\varepsilon=H_0+\varepsilon V\) in a Hilbert space, where the perturbing operator may have a narrower domain than \(H_0\). Under positivity, compactness, and an approximation condition, it proves convergence of the dis…
This paper investigates the catalytic conversion of gamma-keto alcohols with ammonia and amines as a route to pyrrolines, pyrroles, and pyrrolidines. Gamma-acetopropyl alcohol and secondary gamma-acetobutyl alcohol were passed over dehydrating and dehydrogenating catalysts, including alumina, pallad…
This paper develops a family of arbitrary order iterative approximations for finding a simple root of an algebraic or transcendental equation with an analytic complex function. The method rewrites the equation as a fixed point problem using a polynomial multiplier chosen so that successive derivativ…
This study examines the preparation and phenylating behavior of diphenylbromonium and diphenylchloronium salts, comparing them with known diphenyliodonium compounds. The authors report improved synthetic conditions that raise the yield of diphenylbromonium salts and describe reactions showing both h…
This paper treats a plane elasticity contact problem in which a rigid flat punch presses on an elastic half-plane containing a symmetrically placed circular hole near the contact region. Using Kolosov-Muskhelishvili complex potentials and a modification of Sherman’s method, the doubly connected doma…
This paper proposes a finite difference method for the approximate solution of the Dirichlet problem for Laplace’s equation, with attention to how computational work depends on the amount of boundary data needed to prescribe the solution to a given accuracy. For two-dimensional domains with prescrib…
This discussion article replies to A. S. Gorshkov’s criticism of I. N. Butakov’s approach to energy balances and efficiency indicators for combined heat and power plants. Butakov defends the need to evaluate both overall plant efficiency and partial efficiencies by output type, arguing that mechanic…
This paper criticizes I. N. Butakov’s use of overall fuel heat utilization as an indicator for evaluating combined heat and power plants. Through a numerical example of a back pressure turbine unit, it compares specific electricity generation, specific heat consumption, economic efficiency, and over…
This paper examines how the hydraulic characteristic of a regulator control element in an internal combustion engine cooling system depends on the resistance of the complete installation. Using head loss relations, measured cooling jacket resistances for several engines, and valve flow data, it deri…
The paper critiques the Ministry of Electric Power Stations method for calculating technical and economic indicators of combined heat and power plants, arguing that it incorrectly assigns heat-flow losses between boilers and turbines entirely to electric-power generation while treating the heat-supp…
The paper examines how to calculate the cost of energy products generated by recovery units attached to open-hearth furnaces. It argues that the fuel component must be included in such calculations, since omitting it prevents evaluation of the reduction in primary heat consumption attributable to en…
The article develops a method for determining absolute fuel savings from installations that use secondary energy resources, arguing that the recovered heat alone does not measure the true saving. Using heat and energy balances for a combined technological and power-supply system, the author derives …
This paper examines the choice between qualitative, quantitative, and mixed regulation of heat supply in district heating networks served by a combined heat and power plant. It develops equations linking outdoor temperature, relative heat load, supply and return water temperatures, extraction steam …
This paper examines how to choose between qualitative, quantitative, and mixed regulation of heat supply in district heating networks from an energy efficiency standpoint. It develops relations linking outdoor temperature, relative heat load, supply temperature, extraction steam pressure, turbine he…
This paper reexamines the criteria for determining when steam drives or electric drives are preferable for industrial working machines. It argues that Melent’ev’s special comparative criterion is unnecessary, and instead derives fuel consumption and fuel saving relations using standard efficiency co…
This paper examines the recovery of chemical and sensible heat from air-blast gas produced as a by-product in intermittent water-gas generation. It reviews possible utilization schemes, analyzes operating conditions needed for stable recovery, and reports tests at an existing three-generator station…
This paper proposes an indirect method for determining gas volumes and heat losses during balance testing of boiler units, addressing the measurement and reliability difficulties of conventional heat-balance and ash-balance approaches. The method uses the heat balance of a selected heat-utilizing su…
This paper presents a direct derivation of equations relating the elemental composition of solid and liquid fuels to the composition of dry combustion products. Instead of obtaining the relation indirectly through auxiliary calculations, the author bases the derivation on volume changes accompanying…
The paper addresses transient heating of bodies of simple geometry by high-temperature radiant heat, where the boundary heat flux follows the Stefan-Boltzmann law and is difficult to combine directly with the heat-conduction equation. It proposes a time-zonal finite-difference procedure that uses kn…
This paper examines the mathematical expression of the first law of engineering thermodynamics for reversible and irreversible processes, with particular attention to friction and flow. It argues that some contemporary textbook formulations incorrectly treat the heat equivalent of frictional work as…
This paper develops a nonstationary method for determining moisture conductivity and thermal moisture conductivity coefficients in moist spherical bodies, intended to avoid the long duration and apparatus complexity of stationary methods. It formulates coupled heat and moisture exchange equations fo…
The paper examines coupled nonstationary heat and moisture transfer in moist capillary porous materials under conditions where internal moisture evaporation is neglected. For an infinite plate with prescribed surface temperature and moisture insulation, it formulates the governing temperature and mo…
This article traces the development of electric power in Siberia from the first municipal electrification initiatives in Tomsk in the 1890s through the rapid expansion associated with Soviet industrialization and the first two five-year plans. Using archival records, statistical yearbooks, published…
This paper critiques the prevailing indirect theory of radiation injury, which attributed biological damage chiefly to products of water radiolysis, and argues that direct interactions with tissue constituents must also be considered. The authors propose that high-energy betatron radiation can ioniz…
This experimental study examines hematological changes in rabbits, guinea pigs, and rats after general irradiation with 10 MeV betatron rays at single, repeated, and fractionated doses. The author follows peripheral blood indices, leukocyte differentials, cell morphology, reticulocytes, erythrocytes…
This experimental study examines the pathological anatomy of acute radiation sickness in adult guinea pigs after single whole-body exposure to rays generated by a betatron, with attention to deaths within 12 hours and within 10 days after irradiation. Histological analysis describes widespread vascu…
This paper examines radiation safety and laboratory organization for work with an 11 MeV betatron, using counter measurements and a calibrated microdosimeter to assess scattered radiation, induced activity, and personnel exposure in different rooms and work positions. The authors report that radiati…
This article describes the adaptation of a 10 MeV betatron for biological and medical research, with emphasis on its suitability for deep radiation therapy. It compares betatron radiation with conventional X-rays, then presents the design and calculation of a lead collimator with replaceable apertur…
