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Submit scientific paper, scientific publications, International Research Journal | Meždunarodnyj naučno-issledovatel’skij žurnal

PHYSICS AND MATHEMATICS

ISSN 2227-6017 (ONLINE), ISSN 2303-9868 (PRINT), DOI: 10.18454/IRJ.2227-6017
ПИ № ФС 77 - 51217, 16+

NUMERICAL MODELING OF ONE-DIMENSIONAL THERMALLY STRESSED STATE OF A ROD FIXED AT TWO ENDS WITH DIFFERENT HEAT SOURCES

Posted in 2020, Issue №2(92) February 2020, PHYSICS AND MATHEMATICS | 0 comments

The computational algorithm is developed and the thermo-stress-strain state of a rod fixed at two ends with a constant cross section depending on the presence of partial thermal insulation, heat flux and heat exchanges is numerically investigated, based on energy principles, focused on minimization of total thermal energy of elastic deformations combined with the use of a quadratic finite element with three nodes.

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MATHEMATICAL MODELING OF ONE-DIMENSIONAL THERMALLY STRESSED STATE (THERMOELASTICITY) OF A ROD FIXED AT TWO ENDS WITH DIFFERENT HEAT SOURCES

Posted in 2020, Issue №2(92) February 2020, PHYSICS AND MATHEMATICS | 0 comments

The mathematical model of a rod with a constant cross section fixed at both ends is developed depending on the presence of partial thermal insulation, heat flux, and heat exchanges based on energy principles, focused on minimization of total thermal energy of elastic deformations combined with the use of a quadratic finite element with three nodes.

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MAIN FEATURES OF THE STAND FOR THE CREATION OF A MAGNETO-OPTIC TRAP FOR CALCIUM-40 ATOMS

Posted in 2020, Issue №2(92) February 2020, PHYSICS AND MATHEMATICS | 0 comments

A stand was created for laser cooling and trapping of calcium atoms in a magneto-optical trap (MOT). MOT was obtained from calcium-40 atoms and its parameters were optimized. A narrow fluorescence resonance of an atomic calcium beam was observed. The frequency and width of the resonance at the 4s3d 1D2 – 4s5p 1P1 calcium-40 transition were measured by increasing the resonance fluorescence intensity in the MOT.

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SYNTHESIS OF PROCESSES BUSINESS DIRECTORY AND THE ELECTRONIC DOCUMENT MANAGEMENT SYSTEM BASED ON IBM LOTUS NOTUS\DOMINO

Posted in 2014, Issue June 2014, PHYSICS AND MATHEMATICS | 0 comments

Considered software IBM Lotus Notes \ Domino and developed on the basis of its electronic document management system. R & D is to provide integration into the electronic document directory of business processes, for the classification of the enterprise. The process of receiving through the reporting system, and a comparison to give statements at the working directory of business processes. The results obtained allow us to speak about the advantages of directory integration of business processes in electronic document management system, in the absence of the need to provide graphical reporting.

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OPTIMAL STRATEGIES MULTIPRODUCT FOOD BUSINESSOPERATION USING GENETIC ALGORITHMS AND PARTICLE SVARM

Posted in 2014, Issue May 2014, PHYSICS AND MATHEMATICS | 0 comments

In this paper the authors propose an optimization problem of control over the operation of the company, which produces food products with a large range of items delivered in the form of a nonlinear programming problem with a vector criterion, for which we have developed a modified genetic algorithm, and also one of the innovative heuristic methods, particle swarm optimization. The developed software using two algorithms of optimization on the user selection – genetic algorithm or particle swarm optimization algorithm.

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COMPUTER MODELLING OF SMALL MOLECULES OF ORGANIC AZIDES ON THE BASIS OF HN3, CH3N3, NCN3, C2H5N3, NCCH2N3

Posted in 2014, Issue May 2014, PHYSICS AND MATHEMATICS | 0 comments

The theoretical calculations, made by using density functional theory, and the analysis of fundamental properties of small molecules of organic azides HN3, CH3N3, NCN3, C2H5N3, NCCH2N3 (molecular structure, electron and vibrational spectra, elements of chemical bond, thermodynamic functions, space distribution of electron density) have been given in the article. The applicability of B3LYP/TZVP method for prognostication of various structures is proved by experimental confirmation of theoretical data.

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INFORMATION SYSTEM FOR MONITORING RESIDENTIAL BUILDINGS

Posted in 2014, Issue May 2014, PHYSICS AND MATHEMATICS | 0 comments

The article briefly describes the development of the information system (IS) for monitoring residential buildings. Different from an existing IS is the ability to obtain the list of the most probable causes of the defects at the building structure.

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ABOUT THE ORIGINAL PROPERTIES OF PHOTOGRAPHIC GELATINS

Posted in 2014, Issue May 2014, PHYSICS AND MATHEMATICS | 0 comments

The abnormal phosphorescence of organic compounds for the first time found in work (photographic gelatin of various activity), testifies that they can be considered as organic semiconductors. To this fact also points structure existence in a phosphorescence spectrum of gelatins.

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GELATIN AS ORGANIC SEMICONDUCTOR

Posted in 2014, Issue May 2014, PHYSICS AND MATHEMATICS | 0 comments

In work it is shown that photographic gelatin serves not only as a matrix, in which there are microcrystals of halogenides of silver; they are the active transmitter of electrons from gelatin to microcrystals of halogenides of silver.

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ABOUT ABNORMAL PHOSPHORESCENCE OF ORGANIC SEMICONDUCTORS

Posted in 2014, Issue May 2014, PHYSICS AND MATHEMATICS | 0 comments

Investigating the luminescent properties of organic semiconductors, in particular poly-N-vinilcarbazol, the abnormal phosphorescence, i.e. nonmonotonic decrease of attenuation, was found, especially in the pure. The range of times, characteristic for abnormaliy, in the case with poly-N-vinilcarbazol is less, than for gelatin.

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CONTINUITY OF SOLUTION OF INVERSE PROBLEMS FOR THE EQUATION OF RADIATION TRANSFER

Posted in 2020, Issue № 01(91) January 2020, PHYSICS AND MATHEMATICS | 0 comments

The theory of inverse problems for the particle transport equation is one of the rapidly developing areas of modern mathematics. This article discusses the continuity of the solution of inverse problems for the radiative transfer equation in multi-zone regions from R. In fact, the inverse problem is studied for the non-stationary radiative transfer equation, which consists in simultaneously finding the scattering coefficient ss and radiation intensity u. In this case, it suffices to prove the continuity of the solution of the inverse problem from R with respect to additional information. In this paper, we study the local properties of the classical solution of the single speed time-dependent equation considered in a multi-zone domain.

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OPTICAL PROPERTIES OF FILMS BASED ON POLYMETHYL METHACRYLATE DOPED WITH β -DIKETONATES OF BORON DIFLUORIDE

Posted in 2020, Issue № 01(91) January 2020, PHYSICS AND MATHEMATICS | 0 comments

The linear and non-linear optical characteristics of new polymeric materials based on polymethyl methacrylate doped with β-diketonates of boron difluoride are studied in the article. The obtained samples showed a high output of one- and two-photon fluorescence and high two-photon absorption coefficients. Spectral characteristics of the samples enable the use of the studied materials as fluorescent concentrators of solar energy.

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ANALYTICAL FUNCTIONS OF AN COMPLEX VARIABLE WITH PARAMETERS

Posted in 2019, Issue № 12(90) December 2019, PHYSICS AND MATHEMATICS | 0 comments

In this paper, we consider the analytic functions of a complex variable with small parameters generated by some operators. We study the asymptotic behavior of a function with respect to a small parameter. The problem is solved using line-level harmonic functions. The analytic domain of the function is divided by some lines into parts, and in some parts the limits (by a small parameter) exist, but in others they are infinite or do not exist.

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ON GRAVITATION MECHANISM

Posted in 2019, Issue № 12(90) December 2019, PHYSICS AND MATHEMATICS | 0 comments

The analysis of the gravitation process mechanism is carried out using the condition of a stationary state in wave-particle interactions and within the framework of non-relativistic mechanics. The author obtained an equation of the functional dependence of the constant of gravity on the electric constant. It is assumed that gravity is the wave contribution from the mass of charged particles when they move in the field of central forces.

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SOME ASPECTS OF INTEGRAL GRAHANGE METHOD APPLICATION FOR DESCRIPTION OF FEATURES OF DEEP-WATER DRAINING OF OIL PRODUCTS IN CASE OF MARINE PIPELINES DAMAGE

Posted in 2019, Issue № 12(90) December 2019, PHYSICS AND MATHEMATICS | 0 comments

The author uses a mathematical model describing the propagation of a multiphase flooded jet caused by the damage to the oil-producing structure or the marine pipeline used for the transportation of hydrocarbons. The flow features of multiphase and single-phase (gas) jets are studied. The author also studied the effect of hydrate formation on the jet parameters. The integral Lagrange method is used to calculate the thermophysical parameters. As a result of these calculations, the author obtained the dependences of temperature and velocity on the vertical coordinate. Data analysis of dependencies allows predicting jet behavior and study the possibilities of application of devices for leak detection.

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FEATURES OF CRYSTALLOGRAPHIC STRUCTURE OF CeO2 BUFFER LAYERS ON r-Al2O3 OBTAINED BY PULSE LASER DEPOSITION METHOD

Posted in 2019, Issue № 12(90) December 2019, PHYSICS AND MATHEMATICS | 0 comments

The paper presents the results of structural studies of CeO2 buffer layers grown by pulsed laser deposition on single-crystal substrates of r-Al2O3 ( ) at a substrate temperature of 750°C. It was shown experimentally that when the oxygen pressure changes during growth, while maintaining the remaining growth parameters unchanged, it is possible to obtain buffer layers with different crystallographic orientations: at an oxygen pressure of 0.002 mbar, the buffer layers have an orientation of (111), and at an oxygen pressure of 0.2 mbar – (002). The results obtained may be of interest for the preparation of epitaxial films and nanoheterostructures with layers of high-temperature superconductors and doped manganites on r-Al2O3 single-crystal substrates with CeO2 buffer layers.

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CALCULATION OF THE PHOTOIONIZATION CROSS SECTIONS FOR THE IONS OF THE CESIUM ISOELECTRONIC SEQUENCE BY THE DIRAC-FOCK METHOD

Posted in 2019, Issue № 12(90) December 2019, PHYSICS AND MATHEMATICS | 0 comments

The photoionization cross sections for the ground and same excited states of 10 ions cesium isoelectronic sequence from Ba+ through Tb10+ are calculated by the relativistic Dirac-Fock self-consistent field method. The energy dependence of the photoionization cross sections and the changes in the threhold values along the isoelectronic sequence are considered. Along with the total photoionization cross sections, the asymmetry parameter in the angular distribution of photoelectrons and the degree of their polarization ara also colculated.

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TWO-CENTER OVERLAP INTEGRALS – IT IS SIMPLY

Posted in 2014, Issue April 2014, PHYSICS AND MATHEMATICS | 0 comments

Integrals on space of functions dependent on radiuses-vectors drawn from two given centers in any point are key concept of physical chemistry. Here the scheme is offered which allows at required precision execute numerical integration of two-centered functions without of their decomposition in series, resorting to recurrent relations and to other approached methods. In case of simple functions the scheme allows execute their integration analytically.

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USE OF COMPUTER TECHNOLOGIES IN EDUCATIONAL PROCESS WHEN TRAINING IN PHYSICS

Posted in 2014, Issue April 2014, PHYSICS AND MATHEMATICS | 0 comments

In article creation and use of computer information technologies when training in physics is considered.

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THE LINEAR ANALYSIS OF MODELS OF SMALL WATER TAKING INTO ACCOUNT HETEROGENEITY OF THE BOTTOM

Posted in 2014, Issue April 2014, PHYSICS AND MATHEMATICS | 0 comments

The results of the linear analysis of the dynamics of small perturbations in the shallow water models are discussed. Boundary problems of Storm Liouville for Saint-Venant’s equations and the modified model in approach of Boussinesq in case of a rough bottom are solved. Features of dependences of own frequency from wave number are disputed.

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