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2020

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Full-Text Articles in Physical Sciences and Mathematics

Аn Optical Study Of Strain Relaxation And Interdiffusion In Znse/Zncdse Quantum Wells Modified By Γ-Irradiation, Muratbay B. Sharibaev, Kanatbay A. Ismailov, Ibrohim N. Karimov, Murodjon Z. Nosirov Dec 2020

Аn Optical Study Of Strain Relaxation And Interdiffusion In Znse/Zncdse Quantum Wells Modified By Γ-Irradiation, Muratbay B. Sharibaev, Kanatbay A. Ismailov, Ibrohim N. Karimov, Murodjon Z. Nosirov

Scientific Bulletin. Physical and Mathematical Research

If we turn to the literature data, it is known that the degradation of CdZnTe / ZnTe and CdZnSe /ZnSe quantum wells and usually includes two types of processes: (i) fast (as called dynamic, by analogy with the degradation of heterostructures based on A3B5 materials) - germination and propagation of extended defects from a GaAs substrate. This process in CdZnSe / ZnSe is slowed down by various technological methods (treatment of a substrate in sulfur; reduction of a damaged layer in a GaAs substrate; deposition of a GaAs epitaxial buffer layer; use of the concept of compensation of bipolar stresses; …

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Obtaining, Structure And Electrophysical Properties Of The Solid Solution (Gaas1-Δbiδ)1-X-Y(Ge2)X(Znse)Y, Hotamjon Mansurov, Akramjon Boboev, Johongir Usmonov, Xushruybek Mahmudov, Dilkhayotjon Pulatjon Ugli Abdurakhimov Dec 2020

Obtaining, Structure And Electrophysical Properties Of The Solid Solution (Gaas1-Δbiδ)1-X-Y(Ge2)X(Znse)Y, Hotamjon Mansurov, Akramjon Boboev, Johongir Usmonov, Xushruybek Mahmudov, Dilkhayotjon Pulatjon Ugli Abdurakhimov

Scientific Bulletin. Physical and Mathematical Research

This work shows the possibility of growing a single-crystal substitutional solid solution (GaAs1-δBiδ)0.46(Ge2)0.31(ZnSe)0.23on GaP substrates by liquid phase epitaxy from a bismuth-containing melt solution. was shown that tetrahedral bonds in the (GaAs1-δBiδ)0.46(Ge2)0.31(ZnSe)0.23 layers are enriched with arsenide gallium molecules, and some GaAs1-δBiδ molecules are replaced by Ge2 paired atoms and ZnSe molecule compounds. Experimental results showed that in the epitaxial film, the molar content of GaAs …

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Drawing Parallels In Art Science For Collaborative Learning: A Case Study, Karen Westland Dec 2020

Drawing Parallels In Art Science For Collaborative Learning: A Case Study, Karen Westland

The STEAM Journal

This research paper explores drawing as a tool to facilitate interdisciplinary practice. Outlined is the personal experience of PhD researcher [name removed] in their physics/craft research project, combined with thoughts and opinions from collaborators gathered through group discursive interviews. Interdisciplinary projects face interpersonal and conceptually ambiguous challenges which can be addressed through adopting drawing techniques for educational purposes. Findings highlight that drawing can assist across a breadth of applications as a learning tool for everyone, regardless of drawing ability, to improve the functionality of collaborative projects. Specifically, drawing combined with other communication techniques develops a performative communicative approach that enriches …

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Numerical Simulation Of Nonlinear Vibrations Of Discrete Mass With Harmonic Force Perturbation, M. Yusupov, B. A. Akhmedov, Olga Karpova Dec 2020

Numerical Simulation Of Nonlinear Vibrations Of Discrete Mass With Harmonic Force Perturbation, M. Yusupov, B. A. Akhmedov, Olga Karpova

Acta of Turin Polytechnic University in Tashkent

The problem of vibration of a single-mass system under the force excitation of vibration associated with a fixed base by a weightless nonlinear viscoelastic spring is considered. To take into account the rheological properties of the spring material, the Boltzmann-Volterra principle was used. Mathematical models of the problem under consideration are obtained, which are described by integro-differential equations. A solution method based on the use of quadrature formulas has been developed and a computer program has been compiled on its basis, the results obtained are presented in the form of graphs. The influence of nonlinear and rheological properties of a …

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Neutron Pick-Up Reactions In 18o (10 Mev/Nucleon) + Ta, S. Lukyanov, T. Issatayev, B. M. Hue, V. Maslov, K. Mendibayev, S. S. Stukalov, D. Aznabayev, A. Shakhov, K. A. Kuterbekov, A. M. Kabyshev Dec 2020

Neutron Pick-Up Reactions In 18o (10 Mev/Nucleon) + Ta, S. Lukyanov, T. Issatayev, B. M. Hue, V. Maslov, K. Mendibayev, S. S. Stukalov, D. Aznabayev, A. Shakhov, K. A. Kuterbekov, A. M. Kabyshev

Eurasian Journal of Physics and Functional Materials

The availability of new radioactive ion beams has broadened the study of nuclear reactions and nuclear structure. The main mechanism to produce the secondary beams is the fragmentation of the projectile. An alternative method for the production of the exotic nuclei is the multinucleon transfer. We measured production cross section for the B, C, N and O isotopes in the reaction18O + Ta and the beam energy at 10 MeV/nucleon. The cross sections were obtained by integrating the momentum distributions of the isotopes. It was shown that in deep inelastic processes the production yields of different isotopes could …

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Determination Of The Response Function Of The Nai Detector For Γ-Quanta With An Energy Of 4.43 Mev, Formed During Inelastic Scattering Of Neutrons With An Energy Of 14.1 Mev On Carbon Nuclei, S. B. Dabylova, Yu. N. Kopach, S. K. Sakhiyev, D. N. Grozdanov, N. A. Fedorov Dec 2020

Determination Of The Response Function Of The Nai Detector For Γ-Quanta With An Energy Of 4.43 Mev, Formed During Inelastic Scattering Of Neutrons With An Energy Of 14.1 Mev On Carbon Nuclei, S. B. Dabylova, Yu. N. Kopach, S. K. Sakhiyev, D. N. Grozdanov, N. A. Fedorov

Eurasian Journal of Physics and Functional Materials

The work is devoted to determining the response function of the detector NaI(Tl) for γ-quanta with energy of 4.43 MeV, formed during inelastic scattering of neutrons with energy of 14.1 MeV on the nuclei 12 C. In gamma spectrometry, output pulses are recorded, the amplitudes of which are proportional to the energy lost in the detection medium by incident photons. One of the main tasks of radiation detection is to restore radiation characteristics from signals measured at the outputs of detectors. For this, it is necessary to know, first of all, the general characteristics of detectors as converters of radiation …

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Influence Of Electrolytic-Plasma Hardening Modes On Structure And Hardness Of 0.34cr-1ni-Mo-Fe Steel, B. K. Rakhadilov, Z. A. Satbayeva, R. S. Kozhanova, D. R. Baizhan, M. K. Rakhadilov, G. B. Botabayeva Dec 2020

Influence Of Electrolytic-Plasma Hardening Modes On Structure And Hardness Of 0.34cr-1ni-Mo-Fe Steel, B. K. Rakhadilov, Z. A. Satbayeva, R. S. Kozhanova, D. R. Baizhan, M. K. Rakhadilov, G. B. Botabayeva

Eurasian Journal of Physics and Functional Materials

The article presents the results of studying the process of electrolytic-plasma hardening of 0.34Cr-1NiMo- Fe steel by surface hardening, as well as the results of the current-voltage characteristics of the cathodic electrolytic-plasma process depending on the composition of the electrolyte. Temperature-time and special modes of electrolytic-plasma hardening of steel 0.34Cr-1Ni-Mo-Fe were determined. The optimal composition of the electrolyte for electrolytic-plasma hardening has been determined, providing a relatively high heating rate and high hardness of the steel surface. It has been determined that after the electrolytic-plasma hardening, the microhardness of 34KhN1M steel increases 2.9 times due to the formation of fine …

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Study Of The Influence Of The Phase Composition And Crystal Structure Of Fexni100-X Nanostructures On The Efficiency Of Using Lithium Ion Batteries As Anode Materials, D. B. Borgekov, N. A. Hlebnikov, D. I. Shlimas, A. L. Kozlovskiy Dec 2020

Study Of The Influence Of The Phase Composition And Crystal Structure Of Fexni100-X Nanostructures On The Efficiency Of Using Lithium Ion Batteries As Anode Materials, D. B. Borgekov, N. A. Hlebnikov, D. I. Shlimas, A. L. Kozlovskiy

Eurasian Journal of Physics and Functional Materials

The results of the efficiency of using Fe x Ni 100��x nanotubes as anode materials for lithium-ion batteries have been obtained. In the course of research, it was found that an increase in the concentration of nickel in the structure to 40 and 60 at.% leads to a sharp increase in the resource number of cycles by more than two times in comparison with iron nanotubes. Such a difference in the resource lifetime is due to the higher stability of Fe x Ni 100��x nanotubes with a nickel concentration of more than 40 at.% to destruction, as well as resistance …

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Determination Of Radon Levels In Dwellings And Social Objects And Evaluation Annual Effective Dose From Inhalation Of Radon In Stepnogorsk Area Northern Kazakhstan, D. S. Ibrayeva, M. N. Aumalikova, K. B. Ilbekova, M. M. Bakhtin, P. K. Kazymbet Dec 2020

Determination Of Radon Levels In Dwellings And Social Objects And Evaluation Annual Effective Dose From Inhalation Of Radon In Stepnogorsk Area Northern Kazakhstan, D. S. Ibrayeva, M. N. Aumalikova, K. B. Ilbekova, M. M. Bakhtin, P. K. Kazymbet

Eurasian Journal of Physics and Functional Materials

Radon is a noble gas that is one of the natural radioactive decay products of radium resulting from the disintegration of uranium. Humans are exposed to sources of natural radiation activity, being radon and its progeny breathing air responsible for more than 50% of the annual dose received from natural radiation. The aim of this study was to determine the radon concentration in the air in settlements’ dwellings and social objects and calculate the annual effective dose of population from radon on the territory mining activities in Stepnogorsk area. The study has shown that activity concentrations of indoor radon in …

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Assessment Of The Dose Burden And Health Status Of The Uranium Processing Workers Of The Republic Of Kazakhstan, M. N. Aumalikova, D. S. Ibrayeva, K. Ilbekova, P. K. Kazymbet, M. M. Bakhtin, D. D. Janabaev, N. Z. Altaeva Dec 2020

Assessment Of The Dose Burden And Health Status Of The Uranium Processing Workers Of The Republic Of Kazakhstan, M. N. Aumalikova, D. S. Ibrayeva, K. Ilbekova, P. K. Kazymbet, M. M. Bakhtin, D. D. Janabaev, N. Z. Altaeva

Eurasian Journal of Physics and Functional Materials

The main objective of current study is to assess the dose burden and health status of workers at the uranium processing hydrometallurgical plant in order to develop measures aimed at reducing their incidence. This article presents the results of radiation monitoring and data on the health status of workers at the hydrometallurgical plant of the Stepnogorsk Mining and Chemical Combine (SMCC). The data of the accumulated effective dose for the entire length of service, as well as data on the incidence rate for the period 2013-2019, obtained from the base of the Industrial Radiation and Epidemiological Register, have been analyzed. …

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Changes In The Structure And Properties Of Zro2 Detonation Coatings During Annealing, B. K. Rakhadilov, D. N. Kakimzhanov, G. Botabaeva, D. B. Buitkenov, N. Kantai, L. B. Bayatanova Dec 2020

Changes In The Structure And Properties Of Zro2 Detonation Coatings During Annealing, B. K. Rakhadilov, D. N. Kakimzhanov, G. Botabaeva, D. B. Buitkenov, N. Kantai, L. B. Bayatanova

Eurasian Journal of Physics and Functional Materials

The article studied the effect of annealing on the structure and properties of zirconium dioxide coatings obtained by detonation spraying. Detonation spraying was realized on a computerized detonation spray ing complex of the new generation CCDS2000. Determined that coatings made of zirconium dioxide are characterized by high adhesive strength of adherence to the substrate. Thermal annealing of coated samples was performed at temperatures of 900-1200◦C. It was determined that the microhardness of zir conium dioxide coatings increases by 10-25% depending on the annealing temperature after annealing. The results of nanoindentation showed that the nanohardness of the coatings after …

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Investigation Of The Applicability Of Post-Irradiation Annealing To Reduce The Degree Of Disorder In Aln Ceramic To Proton Irradiation, A. L. Kozlovskiy Dec 2020

Investigation Of The Applicability Of Post-Irradiation Annealing To Reduce The Degree Of Disorder In Aln Ceramic To Proton Irradiation, A. L. Kozlovskiy

Eurasian Journal of Physics and Functional Materials

The work presents study results of the applicability of high-temperature heat treatment (500-700°C) of nitride ceramics irradiated with protons with an energy of 1.5 MeV and a dose of 10 16 cm ��2 . It was found that heat treatment for 60 minutes at a temperature of 700°C allows us to significantly reduce the density of radiation-induced defects and distortions in ceramics structure due to partial annihilation and relaxation of point defects. Dependences of changes in the strength and mechanical characteristics of ceramics on the temperature of post-irradiation annealing are shown. Based on the data obtained, a conclusion was made …

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Dft-Based Study Of Electric Field Effect On The Polarizability Of Three Ringed Nematic Liquid Crystal Molecules, Pranav Upadhyay, Mirtunjai Mishra, Ankur Trivedi, Jitendra Kumar, Asheesh Kumar, Devesh Kumar Dec 2020

Dft-Based Study Of Electric Field Effect On The Polarizability Of Three Ringed Nematic Liquid Crystal Molecules, Pranav Upadhyay, Mirtunjai Mishra, Ankur Trivedi, Jitendra Kumar, Asheesh Kumar, Devesh Kumar

Makara Journal of Science

Owing to its successful application to complex molecular systems, computational density functional theory (DFT) has been used to study the effect of an electric field on the molecular polarizability and HOMO–LUMO gap of 1-phenyl-4-{2-[(1s,4r)-4-pentylcyclohexyl]ethyl}benzene (1) and its fluoro-, chloro-, and cyano- derivatives, namely, 1-fluoro-4-(4-{2-[(1s,4r)-4-pentylcyclohexyl]ethyl}phenyl)benzene (2), 1-chloro-4-(4-{2-[(1s,4r)-4-pentylcyclohexyl]ethyl}phenyl)benzene (3), and 4-(4-{2-[(1s,4r)-4-pentylcyclohexyl]ethyl}phenyl)benzonitrile (4). These molecules belong to the family of nematic liquid crystals with three rings: two benzene and one cyclohexane. Furthermore, two DFT approaches, namely, B3LYP and M062X, have been used to examine the results obtained. This study reveals a remarkable feature: the polarizability of these molecules follows nearly a step function …

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A Transformative Approach To Incorporating Adaptive Courseware: Strategic Implementation, Backward Design And Research-Based Teaching Practices, Tonya A. Buchan, Stanley Kruse, Jennifer Todd, Lee Tyson Dec 2020

A Transformative Approach To Incorporating Adaptive Courseware: Strategic Implementation, Backward Design And Research-Based Teaching Practices, Tonya A. Buchan, Stanley Kruse, Jennifer Todd, Lee Tyson

Current Issues in Emerging eLearning

In July 2016, Colorado State University (CSU) joined seven other land-grant institutions in the Accelerating Adoption of Adaptive Courseware grant sponsored by the Personalized Learning Consortium (PLC) of the Association of Public and Land-grant Universities (APLU). A primary objective of the grant was to scale the adoption of adaptive courseware in general education courses at each of the grant institutions. CSU targeted high-enrollment, general education courses and took a three-pronged, transformative approach to the integration of adaptive courseware. Specifically, CSU divided the courseware integration into three components: 1) strategic implementation of courseware, 2) backward course design, and 3) incorporation of …

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Editorial Board Dec 2020

Editorial Board

Karbala International Journal of Modern Science

No abstract provided.

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Rapid Radiological Analysis Of Building Materials, Askar Safarov, Joseph Sharonov, Ali Mukhamedov, Askarali Azimov, Akmal Safarov, Mukhammad Salimov, B Radzhabboev Dec 2020

Rapid Radiological Analysis Of Building Materials, Askar Safarov, Joseph Sharonov, Ali Mukhamedov, Askarali Azimov, Akmal Safarov, Mukhammad Salimov, B Radzhabboev

Scientific Journal of Samarkand University

Measurements of the dose-forming radionuclide concentrations such as Rа-226, Тh-232 and К-40 were carried out in samples of building materials with different ageing times. The radium equivalent activities of the samples were determined. Possible values of the correcting coefficients to the activity of Ra-226 that take into account the radioactive equilibrium were calculated. This, in turn, allows to perform rapid radiological analysis of building materials.

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Explicit Formulas For Solutions Of Maxwell’S Equations In Conducting Media, Valery Yakhno Dec 2020

Explicit Formulas For Solutions Of Maxwell’S Equations In Conducting Media, Valery Yakhno

Applications and Applied Mathematics: An International Journal (AAM)

A new explicit presentation of the fundamental solution of the time-dependent Maxwell’s equations in conducting isotropic media is derived by Hadamard techniques through the fundamental solution of the telegraph operator. This presentation is used to obtain explicit formulas for generalized solutions of the initial value problem for Maxwell’s equations. A new explicit Kirchhoff’s formula for the classical solution of the initial value problem for the Maxwell equations in conducting media is derived. The obtained explicit formulas can be used in the boundary integral method, Green’s functions method and for computation of electric and magnetic fields in conducting media and materials.

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Effect Of Porosity On Unsteady Mhd Convection Flow Past A Moving Vertical Plate With Ramped Wall Temperature, U. S. Rajput, Mohammad Shareef Dec 2020

Effect Of Porosity On Unsteady Mhd Convection Flow Past A Moving Vertical Plate With Ramped Wall Temperature, U. S. Rajput, Mohammad Shareef

Applications and Applied Mathematics: An International Journal (AAM)

The unsteady MHD convective flow of an electrically conducting fluid embedded in a porous medium along moving infinite vertical plate with ramped wall temperature and radiation in a rotating system is investigated here. The fluid taken is incompressible and viscous. The governing PDE’s of the model are solved by using integral transform method. The analytical solutions for the velocity, concentration and temperature are obtained. The expressions for skin friction, rate of mass transfer and heat transfer near the plate are obtained. The effects of various parameters like porosity of the medium, magnetic field, Soret number, thermal radiation, rotation, radiation and …

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Exact Solutions Of Two Nonlinear Space-Time Fractional Differential Equations By Application Of Exp-Function Method, Elahe M. Eskandari, Nasir Taghizadeh Dec 2020

Exact Solutions Of Two Nonlinear Space-Time Fractional Differential Equations By Application Of Exp-Function Method, Elahe M. Eskandari, Nasir Taghizadeh

Applications and Applied Mathematics: An International Journal (AAM)

In this paper, we discuss on the exact solutions of the nonlinear space-time fractional Burgerlike equation and also the nonlinear fractional fifth-order Sawada-Kotera equation with the expfunction method.We use the functional derivatives in the sense of Riemann-Jumarie derivative and fractional convenient variable transformation in this study. Further, we obtain some exact analytical solutions including hyperbolic function.

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Accurate Spectral Algorithms For Solving Variable-Order Fractional Percolation Equations, M. A. Abdelkawy Dec 2020

Accurate Spectral Algorithms For Solving Variable-Order Fractional Percolation Equations, M. A. Abdelkawy

Applications and Applied Mathematics: An International Journal (AAM)

A high accurate spectral algorithm for one-dimensional variable-order fractional percolation equations (VO-FPEs) is considered.We propose a shifted Legendre Gauss-Lobatto collocation (SL-GLC) method in conjunction with shifted Chebyshev Gauss-Radau collocation (SC-GR-C) method to solve the proposed problem. Firstly, the solution and its space fractional derivatives are expanded as shifted Legendre polynomials series. Then, we determine the expansion coefficients by reducing the VO-FPEs and its conditions to a system of ordinary differential equations (SODEs) in time. The numerical approximation of SODEs is achieved by means of the SC-GR-C method. The under-study’s problem subjected to the Dirichlet or non-local boundary conditions is presented …

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Stability Analysis Of Circular Robe’S R3bp With Finite Straight Segment And Viscosity, Bhavneet Kaur, Sumit Kumar, Shipra Chauhan, Dinesh Kumar Dec 2020

Stability Analysis Of Circular Robe’S R3bp With Finite Straight Segment And Viscosity, Bhavneet Kaur, Sumit Kumar, Shipra Chauhan, Dinesh Kumar

Applications and Applied Mathematics: An International Journal (AAM)

In this paper, the effect of viscous force on the linear stability of equilibrium points of the circular Robe’s restricted three-body problem (CRR3BP) with smaller primary as a finite straight segment is studied. The present model comprises of a bigger primary m*1 which is a rigid spherical shell filled with a homogeneous incompressible fluid of density ρ1 and the smaller primary m2 lies outside the shell. The infinitesimal mass m3 is a small solid sphere of density ρ3 moving inside m*1. The pertinent equations of motion of m3 are derived …

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Heat And Mass Transfer In Micropolar Model For Blood Flow Through A Stenotic Tapered Artery, Moses S. Dada, Funmilola Alamu-Awoniran Dec 2020

Heat And Mass Transfer In Micropolar Model For Blood Flow Through A Stenotic Tapered Artery, Moses S. Dada, Funmilola Alamu-Awoniran

Applications and Applied Mathematics: An International Journal (AAM)

Heat and mass transfer in blood flow through a tapered artery with mild stenosis is examined. The blood is considered to be an incompressible, micropolar fluid flowing through a vessel with nonsymmetric axial and symmetric radial axes. The geometry of the model takes into account the shape parameter, tapered angle and height of the stenosis.The variation in the shape parameter is used to describe the changes in the axial shape of the stenosis in the artery. The governing equations for the model, comprising the continuity, momentum, energy, and mass transfer equations are transformed and simplified under the assumption of mild …

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Effect Of Induced Magnetic Field On Mixed Convection Flow In A Vertical Channel With Symmetric And Asymmetric Wall Heating Conditions, Hasan N. Zaidi Dec 2020

Effect Of Induced Magnetic Field On Mixed Convection Flow In A Vertical Channel With Symmetric And Asymmetric Wall Heating Conditions, Hasan N. Zaidi

Applications and Applied Mathematics: An International Journal (AAM)

The present paper concerns the study of the induced magnetic field effect on mixed convection flow of viscous incompressible electrically conducting fluid in a vertical channel with symmetric and asymmetric wall heating conditions with heat generation. A steady, laminar, and fully developed flow is considered. Through the appropriate choice of dimensionless variable, the governing equations are developed and three types of thermal boundary conditions isothermal-isothermal, isoflux-isothermal, and isothermal-isoflux for the left-right wall of the channel have prescribed. The analytical solutions for the velocity field, temperature field, magnetic field, and induced current density have been acquired for three types of thermal …

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Vertical Motion Of The Variable Infinitesimal Mass In The Circular Sitnikov Problem, Abdullah A. Ansari, Sada N. Prasad, Chaman Singh Dec 2020

Vertical Motion Of The Variable Infinitesimal Mass In The Circular Sitnikov Problem, Abdullah A. Ansari, Sada N. Prasad, Chaman Singh

Applications and Applied Mathematics: An International Journal (AAM)

The circular case of Sitnikov problem is studied here when the infinitesimal body varies its mass according to Jeans law and it is moving along the z-axis which is perpendicular to the orbital plane of the two equal spherical primaries. The two primaries are moving in xy-plane on the same circular path. These two primaries are imposing the Newtonian forces on the third variable mass body but not influenced by it. Stability of equilibrium points is examined followed by the derived equations of motion. The time-series solutions of the equation of motion are performed by using the Lindstedt-Poincaré method which …

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Negative Magnetoresistivity In Tl4se3s Crystals, Atef Fayez Qasrawi Nov 2020

Negative Magnetoresistivity In Tl4se3s Crystals, Atef Fayez Qasrawi

Journal of the Arab American University مجلة الجامعة العربية الامريكية للبحوث

The temperature and magnetic field dependencies of the magnetoresistivity of Tl4Se3S crystals have been measured in the temperature region of 195-310 K at magnetic fields up to 1.4 T. The magnetoresistivity is observed to exhibit negative values at all measured temperatures. Increasing the magnetic field intensity leads to larger values of negative magnetoresistivity. The magnetoresistivity as a function of applied field was described by the Khosla-Fischer model for spin scattering of carriers in an impurity band. The temperature dependence of magnetoresistivity has revealed the existence of paramagnetic–ferromagnetic and ferromagnetic–paramagnetic phase transitions at 270 and 220 K, respectively. The existence of …

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Indoor Radon-222 Concentration Levels Measurements And Exhalation Rates Calculations In Some Offices And Rooms Of Aauj During The Winter And The Spring Of 2014, Mohammad Abu-Samreh Nov 2020

Indoor Radon-222 Concentration Levels Measurements And Exhalation Rates Calculations In Some Offices And Rooms Of Aauj During The Winter And The Spring Of 2014, Mohammad Abu-Samreh

Journal of the Arab American University مجلة الجامعة العربية الامريكية للبحوث

In this study, we report on the radon concentration levels, the radon exhalation rate, and the annual effective dose equivalent in 10 buildings of AAUJ during the winter and the spring of 2014 using the CR-39 track detectors. The inspected facilities include 46 offices, 24 labs, seven storage rooms, nine coffee rooms, a cleaning room, eight bathrooms, four Xeroxing rooms, and three meeting rooms. The indoor radon concentration levels were found to vary from 26 to 258 Bq/m3, with an arithmetic mean and standard deviation of 76.6 and 16.2. In general, the bathrooms and stores were found to have a …

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Effect Of Sodium Based Transparent Binders On The Optical Properties Of Gase Thin Films, Ahmad Omar Nov 2020

Effect Of Sodium Based Transparent Binders On The Optical Properties Of Gase Thin Films, Ahmad Omar

Journal of the Arab American University مجلة الجامعة العربية الامريكية للبحوث

The effect of sodium based transparent binders on the optical properties of vacuum evaporated GaSe thin films are explored by means of optical reflectivity and transmittance of the binder, GaSe and GaSe/binder interfaces in the incident light wavelength range of 300-1100 nm. The analysis of the absorption coefficient spectra for the three samples revealed a pronounced red shift in the direct allowed electron transition's energy band gap of the GaSe. In addition, the band tail states of GaSe, which was observed at ~ 0.25 eV, disappeared upon binder coating. The binder coated GaSe films screen the energy band gap of …

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The Effect Of Biologically Synthesized Silver Nanoparticles On The Germination And Growth Of Cucurbita Pepo Seedlings, Salim Bamsaoud Nov 2020

The Effect Of Biologically Synthesized Silver Nanoparticles On The Germination And Growth Of Cucurbita Pepo Seedlings, Salim Bamsaoud

Journal of the Arab American University مجلة الجامعة العربية الامريكية للبحوث

Silver nanoparties were synthesized from aqueous solution of silver nitrate, with different molar ratio of silver (0, 1, 2, and 3M), using leaf extraction of Neem as well as Saisban. The effect of silver nanoparticles of Neem and Saisban solution on seed germination, hypocotyls and semi root lengths of Cucurbita Pepo was investigated. The Cucurbita Pepo seeds were immersed for 20 minutes in silver nanoparticles solution of Neem and Saisban along with distilled water as control. The seeds allowed to grow in petri dishes. The results show no effect on growth percentage while a remarkable change in seeding speed and …

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Dynamical And Thermal Properties Of 850 Nm Vertical Cavity Surface Emitting Laser (Vcsel), Muayad Abusaa Nov 2020

Dynamical And Thermal Properties Of 850 Nm Vertical Cavity Surface Emitting Laser (Vcsel), Muayad Abusaa

Journal of the Arab American University مجلة الجامعة العربية الامريكية للبحوث

Vertical cavity surface emitting laser diodes (VCVSELs) are widely used in different areas especially in telecommunications because of their unique properties compared to other types of lasers. In the present work, we explain the dynamical and thermal properties of 850 nm VCSELs. Specifically, we determine the threshold current, output power for a continuous wave operation and pulsed operation for different pulse durations, the wavelength as a function of (injected current/ dissipated power/ temperature).

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Studying The Linear Complex Pt Symmetric Potential, Roland Lombard Nov 2020

Studying The Linear Complex Pt Symmetric Potential, Roland Lombard

Journal of the Arab American University مجلة الجامعة العربية الامريكية للبحوث

We investigate the spectrum of the linear complex PT symmetric potential V(x) = λ|x| + icx. Semi analytical solutions are given by using properties of the Airy functions. The numerical integration of the differential equation system is discussed. We show that the number of eigenstates with a real eigenvalue is limited, depending on the ratio c/λ and on the quantum number n, reflecting a spontaneous breaking of the PT symmetry. For the ground state ( n = 0), we conjecture the eigenvalue to be real whatever the value of c.

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