Open Access. Powered by Scholars. Published by Universities.®

Physical Sciences and Mathematics Commons

Open Access. Powered by Scholars. Published by Universities.®

Physics

Journal

2018

Institution
Keyword
Publication
File Type

Articles 1 - 30 of 173

Full-Text Articles in Physical Sciences and Mathematics

Table Of Contents Dec 2018

Table Of Contents

Journal of the South Carolina Academy of Science

No abstract provided.


System And Process Of Thermal Neutron Flux Producing By Means Of An Accelerator Base Electron Of 18 Mev, A. Didi, A. Dadouch, H. El Bekkour, O. Jai, F. Bouhal, M. Bencheikh Dec 2018

System And Process Of Thermal Neutron Flux Producing By Means Of An Accelerator Base Electron Of 18 Mev, A. Didi, A. Dadouch, H. El Bekkour, O. Jai, F. Bouhal, M. Bencheikh

Eurasian Journal of Physics and Functional Materials

Neutrons are produced in accelerators by irradiating heavy targets with an electron or proton beam. Produced neutrons are of high energy. The purpose of our work is optimization the neutron flux by MCNP-6 code for production the thermal neutron flux using a moderator and for convertation the fast neutron flux into a thermal neutron flux. In this article, we are interested in a thermal neutron flux due it is useful for method of neutron activation analysis. In conventional sources, the moderator is usually a large volume of water or paraffin around the source. Initially, fast neutrons have energy above 1 …


Structure Study Of Al+Al2o3 Composite By Atomic Force Microscopy, D. S. Koleukh, A. S. Kaygorodov, S. V. Zayats, S. N. Paranin Dec 2018

Structure Study Of Al+Al2o3 Composite By Atomic Force Microscopy, D. S. Koleukh, A. S. Kaygorodov, S. V. Zayats, S. N. Paranin

Eurasian Journal of Physics and Functional Materials

The structure of a metal matrix composite based on aluminum containing 6, 17 and 24 wt % Al2 O3 was studied by atomic force microscopy. The composite was prepared by the method of magneticpulse compaction from aluminum nanopowder obtained by the electric wire explosion method. The samples compacted at 400 ◦ C have more clearly expressed grain boundaries than those obtained at room temperature. The structure of a composite subjected to dynamic plastic deformation is studied.


Synthesis And Investigation Of Optical Properties Of Cdse Quantum Dots With High Quantum Luminescence Yield, A. Z. Kainarbay, T. N. Nurakhmetov, Z. M. Salikhodja, A. M. Zhunusbekov, D. K. Daurenbekov, B. Sadykova, B. Yussupbekova, K. Zhanylysov, A. Kainarbayeva, N. Adalbek, N. Shaken, A. Turmakhanbetova, K. N. Balabekov Dec 2018

Synthesis And Investigation Of Optical Properties Of Cdse Quantum Dots With High Quantum Luminescence Yield, A. Z. Kainarbay, T. N. Nurakhmetov, Z. M. Salikhodja, A. M. Zhunusbekov, D. K. Daurenbekov, B. Sadykova, B. Yussupbekova, K. Zhanylysov, A. Kainarbayeva, N. Adalbek, N. Shaken, A. Turmakhanbetova, K. N. Balabekov

Eurasian Journal of Physics and Functional Materials

In the present work, an attempt to obtain quantum dots with a high quantum luminescence yield has been made. For this purpose, the existing methods of synthesis have been studied; approbation of availability and reproducibility of the results and possibility of obtaining luminescent QD samples in the required spectral region has been made. The optical characteristics, the influence of the synthesis conditions, the possibility of using nanostructured materials for sensitization of solar cells have been studied.


Some Radiation Effects In Ii-Vi Quantum Dots, M. B. Sharibaev, Q. A. Ismailov Dec 2018

Some Radiation Effects In Ii-Vi Quantum Dots, M. B. Sharibaev, Q. A. Ismailov

Eurasian Journal of Physics and Functional Materials

The effect of electron irradiation (E=0.6-1.8 MeV) on the optical characteristics (photoluminescence, PL) of CdTe/ZnTe structures with quantum dots, QDs, was investigated in the temperature range from 4.2 to 250 K. The data on the influence of irradiation on the temperature dependence of PL intensity, energy position and PL line width, W, from QDs were obtained. The narrowing of PL band and the blue shift of the QD peak position are explained by quenching of the low energy component connected with larger QDs. A slight decrease in PL intensity for both QDs and the buffer ZnTe layer as well as …


Influence Of Structural Defects In Silicon On Formation Of Photosensitive Heterostructures Mn4si7-Si-Mn4si7 And Mn4si7-Si-M, T. S. Kamilov, A. S. Rysbaev, V. V. Klechkovskaya, A. S. Orekhov, Sh. Kh. Dzhuraev, A. S. Kasymov Dec 2018

Influence Of Structural Defects In Silicon On Formation Of Photosensitive Heterostructures Mn4si7-Si-Mn4si7 And Mn4si7-Si-M, T. S. Kamilov, A. S. Rysbaev, V. V. Klechkovskaya, A. S. Orekhov, Sh. Kh. Dzhuraev, A. S. Kasymov

Eurasian Journal of Physics and Functional Materials

The paper considers the influence of a transition amorphous layer at the interface between the higher manganese silicide (HMS) Mn 4 Si 7 and silicon doped with manganese (Si ) on the photoelectric properties of heterostructures. The role of the initial structural defects in the near-surface layers of the single-crystal silicon on the penetration of manganese atoms into Si upon doping from the gas phase is shown.It has been established that at high temperatures (T>1050 ◦ C) Mn atoms deposited on the silicon surface group together (due to surface diffusion), forming droplets of liquid manganese, which dissolve the near-surface …


Development Of Thermal Sensors By Implantation Ions P+ And B+ In Different Sides Of Si(111), I. R. Bekpulatov, A. S. Rysbaev, Sh. Kh. Dzhuraev, A. S. Kasymov Dec 2018

Development Of Thermal Sensors By Implantation Ions P+ And B+ In Different Sides Of Si(111), I. R. Bekpulatov, A. S. Rysbaev, Sh. Kh. Dzhuraev, A. S. Kasymov

Eurasian Journal of Physics and Functional Materials

In the method of high-phase ion implantation of P + and B + to different sides of monocrystal silicon we obtained p-i-n- structure, which has a high thermal sensitivity of 2.3 mV/K in a broad band temperature of (20 ÷ 550) K. We studied the distribution profile P and B atoms implanted in the Si gradually decreasing energy. The effect of the subsequent thermal and annealing IR profile on the distribution of the atoms and the characteristics of the temperature sensor was studied.


New Mocd2 Phase In Film Coatings Of Molybdenum-Cadmium System, Yu. Zh. Tuleushev, V. N. Volodin, Y. A. Zhakanbaev Dec 2018

New Mocd2 Phase In Film Coatings Of Molybdenum-Cadmium System, Yu. Zh. Tuleushev, V. N. Volodin, Y. A. Zhakanbaev

Eurasian Journal of Physics and Functional Materials

Ion-plasma sputtering and code position of Mo and Cd ultrafine particles have been used for the first time to prepare solid solutions that are alloys with a concentration up to 57.3 at. % Cd in the film; this confirms the thermal-fluctuation and coalescence of small particles. When coatings are formed by molyb-denum and cadmium nanolayers less than 2 nm in the concentrations range of 60-66 at. % Cd, a new phase was found that was prepared directly in the course of film coating formation; it was identified as the MoCd2 compound with a tetragonal face-centered lattice, with the parameters …


Different Methods Of Correcting The Readings Of The Dvgn-01 Albedo Neutron Dosimeter Placed Behind The Ibr-2m Protection, Yu. V. Mokrov, S. V. Morozova, G. N. Timoshenko, V. A. Krylov, O. B. Badunov, G. A. Seilkhanova Dec 2018

Different Methods Of Correcting The Readings Of The Dvgn-01 Albedo Neutron Dosimeter Placed Behind The Ibr-2m Protection, Yu. V. Mokrov, S. V. Morozova, G. N. Timoshenko, V. A. Krylov, O. B. Badunov, G. A. Seilkhanova

Eurasian Journal of Physics and Functional Materials

The paper presents the results of correction of readings of DVBN-01 albedo dosimeters behind IBR-2M protection, the Neutron Physics Laboratory of the Joint Institute for Nuclear Research (JINR), Dubna, byvarious methods. The neutron spectra were measured at two points behind the IBR-2M protection in the experimental halls, and measurements were carried out with the spherical albedo system at these points. The correction coefficients for DVGN-01 were calculated from the measured spectra based on the data of the spherical albedo system. A good agreement of the coefficients calculated by different methods is shown, which indicates the reliability of the obtained values …


Analysis Of (11li+9be)-Reaction In The Framework Of The Time-Dependent Schrodinger Equation, A. K. Azhibekov, K. A. Kuterbekov, V. V. Samarin Dec 2018

Analysis Of (11li+9be)-Reaction In The Framework Of The Time-Dependent Schrodinger Equation, A. K. Azhibekov, K. A. Kuterbekov, V. V. Samarin

Eurasian Journal of Physics and Functional Materials

Neutron transfer and nucleus breakup cross sections in (11Li + 9Be) -reaction are calculated at energy range up to 32 MeV/nucleon. The evolution of probability density of external weakly bound neutrons of 11Li and the probabilities of neutron transfer and nucleus breakup are determined based on a numerical solution of the time-dependent Schrodinger equation. Our calculation results are agree with the experiment.


The Circular Restricted Four-Body Problem With Triaxial Primaries And Variable Infinitesimal Mass, Abdullah A. Ansari Dec 2018

The Circular Restricted Four-Body Problem With Triaxial Primaries And Variable Infinitesimal Mass, Abdullah A. Ansari

Applications and Applied Mathematics: An International Journal (AAM)

This paper investigates the circular restricted four-body problem in which three primaries are taken as triaxial rigid body which are placed at the vertices of an equilateral triangle and the fourth infinitesimal body is varying its mass with time. We used the Jeans law to determine equations of motion and then evaluated the Jacobi integral. In the next section, we have performed the computational work to draw the graphs of the equilibrium points in different planes, zero velocity curves, surfaces and the Newton-Raphson basins of attraction with the variations of the triaxiality parameters. Finally, we have examined the linear stability …


Soret Effect On Transient Mhd Convective Flow Past A Semi-Infinite Vertical Porous Plate With Heat Sink And Chemical Reaction, K. Choudhury, N. Ahmed Dec 2018

Soret Effect On Transient Mhd Convective Flow Past A Semi-Infinite Vertical Porous Plate With Heat Sink And Chemical Reaction, K. Choudhury, N. Ahmed

Applications and Applied Mathematics: An International Journal (AAM)

This problem concerns with an analytical study of heat and mass transfer on unsteady MHD convective flow past a semi-infinite porous vertical plate in presence of thermal diffusion, heat sink and chemical reaction. A uniform magnetic field is imposed transversely to the plate. The governing equations are solved by perturbation technique. The expressions for the velocity, temperature and concentration fields as well as transport properties are obtained in non-dimensional form. The influence of the physical parameters like magnetic field parameter, Schmidt number, Prandtl number, heat sink parameter, chemical reaction parameter and Soret number on these fields is discussed through graphs …


Numerical Treatment For The Flow Of Casson Fluid And Heat Transfer Model Over An Unsteady Stretching Surface In The Presence Of Internal Heat Generation/Absorption And Thermal Radiation, Mohammed M. Babatin Dec 2018

Numerical Treatment For The Flow Of Casson Fluid And Heat Transfer Model Over An Unsteady Stretching Surface In The Presence Of Internal Heat Generation/Absorption And Thermal Radiation, Mohammed M. Babatin

Applications and Applied Mathematics: An International Journal (AAM)

Several important industrial and engineering problems are very difficult to solve analytically since they are high nonlinear. The Chebyshev spectral collocation method possesses an ability to predict the solution behavior for a system of high nonlinear ordinary differential equations. This method which is based on differentiated Chebyshev polynomials is introduced to obtain an approximate solution to the system of ordinary differential equations which physically describe the flow and heat transfer problem of an unsteady Casson fluid model taking into consideration both heat generation and radiation effects in the temperature equation. Based on the spectral collocation method, the obtained solution is …


Conformable Derivative Operator In Modelling Neuronal Dynamics, Mehmet Yavuz, Burcu Yaşkıran Dec 2018

Conformable Derivative Operator In Modelling Neuronal Dynamics, Mehmet Yavuz, Burcu Yaşkıran

Applications and Applied Mathematics: An International Journal (AAM)

This study presents two new numerical techniques for solving time-fractional one-dimensional cable differential equation (FCE) modeling neuronal dynamics. We have introduced new formulations for the approximate-analytical solution of the FCE by using modified homotopy perturbation method defined with conformable operator (MHPMC) and reduced differential transform method defined with conformable operator (RDTMC), which are derived the solutions for linear-nonlinear fractional PDEs. In order to show the efficiencies of these methods, we have compared the numerical and exact solutions of fractional neuronal dynamics problem. Moreover, we have declared that the proposed models are very accurate and illustrative techniques in determining to approximate-analytical …


Thermoelastic Stress Analysis Of A Functionally Graded Transversely Isotropic Hollow Cylinder In Elliptical Coordinates, Tara Dhakate, Vinod Varghese, Lalsingh Khalsa Dec 2018

Thermoelastic Stress Analysis Of A Functionally Graded Transversely Isotropic Hollow Cylinder In Elliptical Coordinates, Tara Dhakate, Vinod Varghese, Lalsingh Khalsa

Applications and Applied Mathematics: An International Journal (AAM)

This paper is concerned with the axisymmetric thermoelastic problem to investigate the influence of nonlinear heat conduction equation, displacement functions and thermal stresses of a functionally graded transversely isotropic hollow cylinder that is presented in the elliptical coordinate system. The method of integral transform technique is used to produce an exact solution of the heat conduction equation in which sources are generated according to a linear function of the temperature. An explicit exact solution of the governing thermoelastic equation is proposed when material properties are power-law functions with the exponential form of the radial coordinate. Numerical calculations are also carried …


Quasi-Linearization Method With Rational Legendre Collocation Method For Solving Mhd Flow Over A Stretching Sheet With Variable Thickness And Slip Velocity Which Embedded In A Porous Medium, M. M. Khader Dec 2018

Quasi-Linearization Method With Rational Legendre Collocation Method For Solving Mhd Flow Over A Stretching Sheet With Variable Thickness And Slip Velocity Which Embedded In A Porous Medium, M. M. Khader

Applications and Applied Mathematics: An International Journal (AAM)

The quasi-linearization method (QLM) and the rational Legendre functions are introduced here to present the numerical solution for the Newtonian fluid flow past an impermeable stretching sheet which embedded in a porous medium with a power-law surface velocity, variable thickness and slip velocity. Firstly, due to the high nonlinearity which yielded from the ordinary differential equation which describes the proposed physical problem, we construct a sequence of linear ODEs by using the QLM, hence the resulted equations become a system of linear algebraic equations. The comparison with the available results in the literature review proves that the obtained results via …


Similarity Analysis Of Three Dimensional Nanofluid Flow By Deductive Group Theoretic Method, Hemangini Shukla, Hema C. Surati, M. G. Timol Dec 2018

Similarity Analysis Of Three Dimensional Nanofluid Flow By Deductive Group Theoretic Method, Hemangini Shukla, Hema C. Surati, M. G. Timol

Applications and Applied Mathematics: An International Journal (AAM)

The objective of this paper is to obtain similarity solution of three-dimensional nanofluid flow over flat surface stretched continuously in two lateral directions. Two independent variables from governing equations are reduced by applying deductive two parameter group theoretical method. Partial differential equations with boundary conditions are converted into ordinary differential equations with appropriate boundary conditions. Obtained equations are solved for temperature and velocity. The effect of nanoparticles volume fraction on temperature and velocity profile is investigated.


The Basins Of Convergence In The Planar Restricted Four-Body Problem With Variable Mass, Amit Mittal, Monika Arora, Md S. Suraj, Rajiv Aggarwal Dec 2018

The Basins Of Convergence In The Planar Restricted Four-Body Problem With Variable Mass, Amit Mittal, Monika Arora, Md S. Suraj, Rajiv Aggarwal

Applications and Applied Mathematics: An International Journal (AAM)

We have studied the existence, location and stability of the libration points in the model of restricted four-body problem (R4BP) with variable mass. It is assumed that three primaries, one dominant primary and the other two with equal masses, are always forming an equilateral triangle. We have determined the equations of motion of the above mentioned problem for the fourth body which is an infinitesimal mass. The libration points have been determined numerically for different values of the parameters considered. It is found that there are eight or ten libration points out of which six are non-collinear and two or …


Fractional Order Thermoelastic Thick Circular Plate With Two Temperatures In Frequency Domain, Parveen Lata Dec 2018

Fractional Order Thermoelastic Thick Circular Plate With Two Temperatures In Frequency Domain, Parveen Lata

Applications and Applied Mathematics: An International Journal (AAM)

The present investigation is concerned with thermomechanical interactions in the fractional theory of thermoelasticity for a homogeneous isotropic thick circular plate in the light of two-temperature thermoelasticity theory in frequency domain. The upper and lower surfaces of the thick plate are traction free and subjected to an axisymmetric heat supply. The solution is found by using Hankel transform technique and a direct approach without the use of potential functions. The analytical expressions of displacement components, stresses, conductive temperature, temperature change and cubic dilatation are computed in transformed domain. Numerical inversion technique has been applied to obtain the results in the …


Analysis Of A Recent Heat Conduction Model With A Delay For Thermoelastic Interactions In An Unbounded Medium With A Spherical Cavity, Bharti Kumari, Anil Kumar, Manushi Gupta, Santwana Mukhopadhyay Dec 2018

Analysis Of A Recent Heat Conduction Model With A Delay For Thermoelastic Interactions In An Unbounded Medium With A Spherical Cavity, Bharti Kumari, Anil Kumar, Manushi Gupta, Santwana Mukhopadhyay

Applications and Applied Mathematics: An International Journal (AAM)

In this work, we study the thermoelastic interactions in an unbounded medium with a spherical cavity in the context of a very recently proposed heat conduction model established by Quintanilla (2011). This model is a reformulation of three-phase-lag conduction model and is an alternative heat conduction theory with a single delay term. We make an attempt to study the thermoelastic interactions in an isotropic elastic medium with a spherical cavity subjected to three types of thermal and mechanical loads in the contexts of two versions of this new model. Analytical solutions for the distributions of the field variables are found …


Numerical Studies For Mhd Flow And Gradient Heat Transport Past A Stretching Sheet With Radiation And Heat Production Via Dtm, Khadijah M. Abualnaja Dec 2018

Numerical Studies For Mhd Flow And Gradient Heat Transport Past A Stretching Sheet With Radiation And Heat Production Via Dtm, Khadijah M. Abualnaja

Applications and Applied Mathematics: An International Journal (AAM)

This paper presents a numerically study for the effect of the internal heat generation, magnetic field and thermal radiation effects on the flow and gradient heat transfer of a Newtonian fluid over a stretching sheet. By using a similarity transformation, the governing PDEs can be transformed into a coupled non-linear system of ODEs with variable coefficients. Numerical solutions for these equations subject to appropriate boundary conditions are obtained by using the differential transformation method (DTM). The effects of various physical parameters such as viscosity parameter, the suction parameter, the radiation parameter, internal heat generation or absorption parameter and the Prandtl …


Linear Stability Analysis With Solution Patterns Due To Varying Thermal Diffusivity For A Convective Flow In A Porous Medium, Dambaru Bhatta Dec 2018

Linear Stability Analysis With Solution Patterns Due To Varying Thermal Diffusivity For A Convective Flow In A Porous Medium, Dambaru Bhatta

Applications and Applied Mathematics: An International Journal (AAM)

Here we investigate the effect of the vertical rate of change in thermal diffusivity due to a hydrothermal convective flow in a horizontal porous medium. The continuity equation, the heat equation and the momentum-Darcy equation constitute the governing system for the flow in a porous medium. Assuming a vertically varying basic state, we derive the linear system and from this linear system, we compute the critical Rayleigh and wave numbers. Using fourth-order Runge-Kutta and shooting methods, we obtain the marginal stability curves and linear solutions to analyze the solution pattern for different diffusivity parameters.


Restricted Three-Body Problem Under The Effect Of Albedo When Smaller Primary Is A Finite Straight Segment, Shipra Chauhan, Dinesh Kumar, Bhavneet Kaur Dec 2018

Restricted Three-Body Problem Under The Effect Of Albedo When Smaller Primary Is A Finite Straight Segment, Shipra Chauhan, Dinesh Kumar, Bhavneet Kaur

Applications and Applied Mathematics: An International Journal (AAM)

This paper addresses the dynamics of the infinitesimal body in the restricted three-body problem under the effect of Albedo when the smaller primary is a finite straight segment and bigger one is a source of radiation. The measure of diffusive reflection of solar radiation out of the total solar radiation received by a body is Albedo which is measured on a scale from 0 to 1. The equations of motion of the infinitesimal body are derived and it is found that there exist five libration points, out of which three are collinear and the rest are non-collinear with the primaries. …


A New American Electron Ion Collider On The Way: What It Means For Particle Accelerator Science And Duquesne Students, Courtney Boyd Nov 2018

A New American Electron Ion Collider On The Way: What It Means For Particle Accelerator Science And Duquesne Students, Courtney Boyd

D.U.Quark

No abstract provided.


Spectra Of One – And Two Photon Excited Luminescence Of Medical Drugsin Photon Traps, A.K. Kubanov, D.I. Semenov Oct 2018

Spectra Of One – And Two Photon Excited Luminescence Of Medical Drugsin Photon Traps, A.K. Kubanov, D.I. Semenov

Scientific Journal of Samarkand University

A technique for studying the photoluminescence spectra of pharmaceuticals (analgin, paracetamol) was developed for single- and two-photon excitation by a pulse-periodic laser. The technique is based on the fiber-optic recording of photoluminescence spectra using a small-size spectrometer, quartz light guides, and mini cavity cuvettes, which makes it possible to compare the analyzed spectrum with the spectrum of the reference substance.


Laser Spectroscopy Of Ultra-Small Concentration Of Atoms And Aerosols In Various Phase States Of Substance, А.Т. Xalmanov Oct 2018

Laser Spectroscopy Of Ultra-Small Concentration Of Atoms And Aerosols In Various Phase States Of Substance, А.Т. Xalmanov

Scientific Journal of Samarkand University

In this work it is given studying of dynamics and types of physical processes with excited atoms and molecules in atomizer of "graphite furnace". Physical mechanism of increasing atomic-ionization signal for two stepwise excitation schemes was shown. It is shown that the maximum signal is observed for In atoms at the transition 5p 2 Р3/2→6s 2 S3/2→8p 2 P1/2 and for Li, Na, Ag, Au, Pt atoms at the transition (n)s→(m)p→(k)d respectively (where n, k, m and f principal quantum numbers of states). In the result in the experiment photoionization collisional ionization and mechanisms were developed. The results are show …


Probabilities Involving Standard Trirectangular Tetrahedral Dice Rolls, Rulon Olmstead, Doneliezer Baize Oct 2018

Probabilities Involving Standard Trirectangular Tetrahedral Dice Rolls, Rulon Olmstead, Doneliezer Baize

Rose-Hulman Undergraduate Mathematics Journal

The goal is to be able to calculate probabilities involving irregular shaped dice rolls. Here it is attempted to model the probabilities of rolling standard tri-rectangular tetrahedral dice on a hard surface, such as a table top. The vertices and edges of a tetrahedron were projected onto the surface of a sphere centered at the center of mass of the tetrahedron. By calculating the surface areas bounded by the resultant geodesics, baseline probabilities were achieved. Using a 3D printer, dice were constructed of uniform density and the results of rolling them were recorded. After calculating the corresponding confidence intervals, the …


The Battle Between Impeccable Intonation And Maximized Modulation, Timothy M. True Oct 2018

The Battle Between Impeccable Intonation And Maximized Modulation, Timothy M. True

Musical Offerings

Equal temperament represents a way of completing the musical circle, and systematically compensating for the Pythagorean comma. Pythagoras discovered this acoustical problem around 550 B.C., and since that time music theorists have debated how to deal with it. The problem is that no perfect solution exists—something must be compromised. As musical styles developed, specific factors and harmonic tendencies led to the gradual adoption of equal temperament. Early in music history, theorists preferred systems which kept acoustical purity relatively intact. Pythagorean intonation and just intonation serve as two examples. However, the move from modality to tonality decentralized the melody as the …


Analysis Of Clusterization Of C70 Molecules In Benzene Solutions Prepared By Various Methods, U. Makhmanov, O. Ismailova, A. Kokhkharov, S. Bakhramov Sep 2018

Analysis Of Clusterization Of C70 Molecules In Benzene Solutions Prepared By Various Methods, U. Makhmanov, O. Ismailova, A. Kokhkharov, S. Bakhramov

Bulletin of National University of Uzbekistan: Mathematics and Natural Sciences

Self-assembling features of molecules of C70 in benzene solution prepared in two various ways – equilibrium and non-equilibrium – has been investigated experimentally by method of high-resolution transmission electron microscopy. It was demonstrated, that the formation of densely packed monomolecular fullerene aggregates with a diameter of not more than 30 nm in solutions prepared by the equilibrium method (without the use of external mechanical influences on solution). In the case of solutions C70, which were prepared by the non-equilibrium method (stirring of solution of C70 by a mechanical rotator), large quasispherical aggregates of nanoporous structure with …


Electronic Specific-Heat Anomalies In High-TC Cuprates, S. Dzhumanov, E. Karimboev, B. Yavidov Sep 2018

Electronic Specific-Heat Anomalies In High-TC Cuprates, S. Dzhumanov, E. Karimboev, B. Yavidov

Bulletin of National University of Uzbekistan: Mathematics and Natural Sciences

In this work, we study the electronic specific heat $C_e(T)$ of underdoped to overdoped high-$T_c$ cuprates, and identify the nature of anomalies in $C_e(T)$ at the superconducting transition temperature $T_c$ and at temperatures above $T_c$. The doped cuprate superconductor is considered as a multi-carrier model system which is composed of different types of charge carriers. The normal-state electronic specific heat $C_n(T)$ of high-$T_c$ cuprates below a characteristic pseudogap (PG) temperature $T^*$ is calculated taking into account three contributions coming from the excited components of Cooper pairs, the ideal Bose-gas of incoherent Cooper pairs and the unpaired carriers in the impurity …