Publisher: V.N. Karazin Kharkiv National University (Total: 7 journals) [Sort alphabetically]

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East European Journal of Physics
Number of Followers: 2 Open Access journal ISSN (Print) 23124334  ISSN (Online) 23124539 Published by V.N. Karazin Kharkiv National University [7 journals] 
 Vortex Dynamo in Rotating Media
Authors: Michael I. Kopp, Volodymyr V. Yanovsky
Pages: 07  50
Abstract: The review highlights the main achievements in the theory of the vortex dynamo in rotating media. Various models of a vortex dynamo in rotating media are discussed: a homogeneous viscous fluid, a temperaturestratified fluid, a moist atmosphere, and a stratified nanofluid. The main analytical and numerical results for these models obtained by the method of multiscale asymptotic expansions are presented. The main attention is paid to models with a nonspiral external force. For a rotating moist atmosphere, characteristic estimates of the spatial and temporal scales of the generated vortex structures are obtained. New effects of the vortex dynamo in a rotating stratified nanofluid, which arise due to thermophoresis and Brownian motion of nanoparticles, are shown. The results of the analysis of the nonlinear equations of the vortex dynamo in the stationary regime are presented in the form of spiral kinks, periodic nonlinear waves, and solitons.
PubDate: 20230602
DOI: 10.26565/231243342023201
 Numerical Analysis on MHD mixed convection flow of Al_2O_3/H_2O
(AluminumWater) Nanofluids in a Vertical Square Duct
Authors: Bishnu Ram Das, Paramananda Deka, Shiva Rao
Pages: 51  62
Abstract: In this work, we have considered steady laminar magnetohydrodynamics (MHD) mixed convection flow of an electrically conducting fluid in presence of nanoparticles while water as the base fluid in a vertical square duct. The walls of the duct are thermally insulated. In the energy equation, the effect of viscous dissipation and Joule heat is also considered. In this case, the walls of the duct are kept at a constant temperature. By using dimensionless quantities the governing equations of momentum, induction, and energy are first transformed into dimensionless equations. The velocity, temperature, and induced magnetic field profiles are plotted to analyze the effect of different flow parameters. It is found that the nanofluid motion expedite with the increase of the value of the parameters magnetic Reynolds number and Prandtl number. There are some important industrial applications and cooling shows in the industry of the current research. This study observed its importance with the view to increasing the heat transfer efficiency practical application relevant to industry and engineering issues. The issues discussed in this study have not been included in the earlier investigation for steady nanofluid flow due to a square duct. Numerical results are matched with an earlier published work and an excellent agreement between two are observed.
PubDate: 20230602
DOI: 10.26565/231243342023202
 Composite Fermions QED Lagrangian Density in Fractional Formulation
Authors: Amer D. AlOqali
Pages: 63  68
Abstract: Quantum electrodynamics (QED) is a highly precise and successful theory that describes the interaction between electrically charged particles and electromagnetic radiation. It is an integral part of the Standard Model of particle physics and provides a theoretical basis for explaining a wide range of physical phenomena, including the behavior of atoms, molecules, and materials. In this work, the Lagrangian density of Composite Fermions in QED has been expressed in a fractional form using the Riemann‑Liouville fractional derivative. The fractional EulerLagrange and fractional Hamiltonian equations, derived from the fractional form of the Lagrangian density, were also obtained. When α is set to 1, the conventional mathematical equations are restored.
PubDate: 20230602
DOI: 10.26565/231243342023203
 Theoretical Description of even even Platinum Pt186 nucleus using IBM
and (VMI) Models
Authors: Ali K. Aobaid
Pages: 69  75
Abstract: The aim of this study, is to investigate, in a phenomenological way, the backbending effect in platinum Pt186 nucleus, in order to get a good description of the bends by using new parameters. VMI model and interacting boson model IBM1 have been used to perform this research for a heavy mass nucleus (Z = 78). Energy ratios and arrangement of the bands show that the platinum Pt186 have O(6)SU(3) dynamical symmetry. Our current calculations gave results that are reasonably consistent with the most recent experimental data, especially the results calculated according to the VMImodel. Variable moment of inertia has been applied to describe successfully the effect of backbending in deformed eveneven Pt186 nucleus. Backbending was observed in the ground and βbands, due to the change of the moment of inertia but not for (γ1, γ2 bands, because no changing in the moment of inertia.
PubDate: 20230602
DOI: 10.26565/231243342023204
 A Study of the Weakly Bound Structure of Nuclei Around the Magic Number
N=50
Authors: Ruwaida S. Obaid, Ali A. Alzubadi
Pages: 76  84
Abstract: An investigation of the quadrupole deformation of Kr, Sr, Zr, and Mo isotopes has been conducted using the HFB method and SLy4 Skyrme parameterization. The primary role of occupancy of single particle state 2d5/2 in the existence of the weakly bound structure around N=50 is probed. Shell gaps are performed using a few other calculations for the doubly magic number 100Sn using different Skyrme parameterizations. We explore the interplays among neutron pairing strength and neutron density profile in two dimensions, along with the deformations of 100Sn.
PubDate: 20230602
DOI: 10.26565/231243342023205
 Describe of Nuclear Structure for Germanium (_32^66)Ge_34) Nucleus under
frame (IBM1, GVMI and VMI) Models
Authors: Imad A. Hamdi, Ali K. Aobaid
Pages: 85  90
Abstract: In this paper, the interacting bosons model1 (IBM1), a variable moment of inertia (VMI) and generalized moment of inertia (GVMI) models were used to calculate the energy levels of the positive parity and its gamma transitions as a function of the angular momentum of eveneven (_32^66Ge_34) nucleus. To determine the dynamic symmetry of this nucleus, the ratios of the energy levels (E_4^+)⁄(E_2^+ ), (E_6^+)⁄(E_2^+), and (E_8^+)⁄(E_2^+) were evaluated and compared with experimental energy values and the ideal scheme of the three dynamic symmetries SU(5), SU(3), and O(6). The current study showed that the dynamic symmetry of this nucleus is determined to be O(6)  SU(5). The intersection of the energy band and the phenomenon of back bending were also studied using the (VMI) and (GVMI) models. These consequences were compared with the experimental results, and the results obtained have been in good agreement.
PubDate: 20230602
DOI: 10.26565/231243342023206
 Shell Model Investigation of Some p and sdShell Nuclei with Harmonic
Oscillator and Skyrme Interactions
Authors: Sarah M. Obaid, Shaimaa A. Abbas, Aeshah Ali Hussein, Noor Adil Mohammed, Fouad A. Majeed
Pages: 91  97
Abstract: In this study, the longitudinal charge and form factors for the nuclei 9Be and 28Si lying in the p and sd shells are studied by employing the Harmonic Oscillator potential (HO) and Skyrme effective interaction (Sk35−Skzs∗). The C0 and C2 from factors calculated for the ground state 3/2, the 5/2 (2.429 MeV) and 7/2 (6.380 MeV) for 9Be, while the ground state 0+ and 2+ (1.779 MeV) state for 28Si nucleus. Calculations of microscopic perturbations that involve intermediate oneparticle, onehole excitation from the core and MS orbits into all upper orbits with excitations are utilized to generate the effective charges necessary to account for the “core polarization effect”. The shell model calculations are utilized on the extended model space to include all 1s, 1p, 2s–1d, 2p‑1f orbits with truncation. BohrMottelson collective model and Tassie model with properly estimated effective neutron and proton charges are taken into account to consider the effect of the core contribution. The estimated form factors were compared with the measured available data and they were in good agreement for most of the studied states. A conclusion can be drawn that truncation is very good choice to study the longitudinal form factors. The choice of Harmonic Oscillator potential (HO) and Skyrme effective interaction (Sk35−Skzs∗) is adequate for form estimation of longitudinal form factors. The estimation of the effective charges based on microscopic perturbations that involve intermediate oneparticle, onehole excitation from the core and MS orbits into all upper orbits with excitations is adequate. The truncation proves to be very successful to perform the study.
PubDate: 20230602
DOI: 10.26565/231243342023207
 Dual Solutions of Hybrid Nanofluid Flow Over a Cone with the Influence of
Thermal Radiation and Chemical Reaction and Its Stability Analysis
Authors: Debasish Dey, Rupjyoti Borah, Ashim Jyoti Baruah
Pages: 98  106
Abstract: The main intention of this study is to differentiate the stable and realisable solutions between the dual solutions of the waterbased hybrid nanofluid flow driven by a solid cone along with energy transfer in the form of heat and mass by employing a new approach called stability analysis. The deviation of thermal radiation, chemical responses and heat absorption/generation are reserved into account. The leading equations which support the mathematical representation of this study are renovated by utilizing a set of similarity variables and solved by the MATLAB builtin bvp4c solver scheme. The outcomes of this study are presented both graphically and numerically. From this study, two kind of flow solutions have been achieved where one of them is related to the timeindependent solutions and stable in nature. Also, the speed of the hybrid nanofluid can be controlled by applying magnetic field, but we should keep in mind that excessive amount of magnetic parameter may damage the system by burning.
PubDate: 20230602
DOI: 10.26565/231243342023208
 Numerical Solution of Radiative Boundary Layer Flow in Porous Medium Due
to Exponentially Shrinking Permeable Sheet Under Fuzzy Environment
Authors: Amir Barhoi, G.C. Hazarika, Hrishikesh Baruah, Pranjal Borah
Pages: 107  116
Abstract: In this paper we are considering a fluid flows problem that contains two equation of motions and more than two parameters in the governing equation of motion. Which is namely Radiative Boundary Layer Flow in Porous Medium due to Exponentially Shrinking Permeable Sheet. The parameter are K=ck0/Lθ, Pr=μcp/κ∞, N=4σ1(T∞)3/(3κ1κ∞), and ε denote the permeability parameter, Prandtl number, and radiation parameter and is the thermal conductivity variation parameter, respectively. The governing differential equation can be obtained by using the similarity variable technique, and then the governing equation of motion can be Fuzzified by the help of Zadeh extension theorem. The technique is used for the validation of the uncertainty of the equation of the motion. The effect of the K, Pr, N, and ε are discussed with the fuzzified governing equation of motion under fuzzy environment. It is observed none of the parameters are directly involved in the occurrence of the uncertainty of the solutions. The uncertainty occurs in the problem is due to the assumption and the numerical computation. Finally, the solution is being carried out under fuzzy environment. It is found that the increasing values of permeability parameter, the values of both the numbers Skin friction coefficient as well as Nusselt number are increases.
PubDate: 20230602
DOI: 10.26565/231243342023209
 Involving NikiforovUvarov Method in Schrodinger Equation Obtaining
Hartmann Potential
Authors: Mahmoud A. AlHawamdeh, Abdulrahman N. Akour, Emad K. Jaradat, Omar K. Jaradat
Pages: 117  123
Abstract: The total wave function and the bound state energy are investigated by involving the NikiforovUvarov method to the Schrodinger equation in spherical coordinates employing Hartmann Potential (HP). The HP is considered as the noncentral potential that is mostly recognized in nuclear field potentials. Every wave function is specified by a principal quantum number n, angular momentum number l, and magnetic quantum number m. The radial part of the wave function is obtained in terms of the associated Laguerre polynomial, using the coordinate transformation x=cosθ to obtain the angular wave function that depends on inverse associated Legendre polynomials.
PubDate: 20230602
DOI: 10.26565/231243342023210
 On Accounting for Own Fields of Emitters when Describing Generation Modes
Authors: Volodymyr M. Kuklin, Eugen V. Poklonskiy
Pages: 124  131
Abstract: The paper discusses three different modes of electromagnetic field generation by an ensemble of oscillators placed at the radiation wavelength in the onedimensional case. The excitation of the resonator field is considered, which, as a rule, is determined by the geometry of the system, with and without taking into account the eigenfields of the emitters. The superradiance regime of the same ensemble of oscillators is also analyzed. In fact, superradiance is formed due to the emitters' own fields even in the absence of a resonator. It is noted that the maximum achievable amplitudes of induced fields both in the superradiance regime and in the regime of excitation of the resonator field are comparable. This makes us think about the role of the selffields of emitters in electronic devices. It is shown that in describing the resonator excitation mode, in addition to the resonator field, it is also necessary to take into account the sum of the natural fields of the emitters in the active zone. Synchronization of emitters leads not only to an increase in the resonator field, but also, as in the superradiance regime, it significantly increases the amplitude of the sum of the oscillator fields. It is shown that in the practically interesting case of open systems (dissipative generation modes), taking into account the eigenfields of the emitters significantly reduces the characteristic time for the development of the generation process and increases the maximum achievable oscillation amplitude. This account also changes the conditions for achieving the maximum energy flow from the system. This can change the operating point of the generation process, which is determined by the requirement for the maximum rate of energy output from the system.
PubDate: 20230602
DOI: 10.26565/231243342023211
 Determination of Band Structure and Compton profiles for AluminumArsenide
Using Density Functional Theory
Authors: Sameen F. Mohammed, Salah M.A. Ridha, Abdulhadi Mirdan Ghaleb, Zahraa Talib Ghaleb, Yamina Benkrima, Mahran Abdulrhman Abdullah
Pages: 132  137
Abstract: Firstprinciples computations of the electrical characteristics of AlAs have been carried out using the density functional theoryDFT and the Local Density ApproximationLDA,methods (DFT) and Generalized Gradient ApproximationGGA. We utilized the CASTEP's plane wave basis set implementation for the total energy computation (originally from Cambridge Serial Total Energy Package). We used to look at the AlAs structure's structural parameter. The band gap was overestimated by the Generalized Gradient Approximation and LDA techniques, although the band gap predicted by the GGA is more in line with the experimental finding, according to the electronic structure calculation utilizing the two approximations. A semiconductor with a straight bandgap of 2.5 eV is revealed by the GGA calculation. The energy band diagram is used to calculate the total and partial densities of AlAs states. Multiple configurations of the ionic model were calculated. of Al+xAs−x (0.0 ≤ x ≤ 1) are also performed utilizing freeatom profiles. According to the ionic model, 0.75 electrons would be transferred from the valence 5p state of aluminum to the 3p state of Arsenide.
PubDate: 20230602
DOI: 10.26565/231243342023212
 Electroexcitation Form Factors and Deformation of 20,22Ne Isotopes Based
on the Shell Model and HartreeFock plus BCS Calculations
Authors: Omar A. Alswaidawi, Ali Alzubadi
Pages: 138  149
Abstract: Nuclear structure of 20,22Ne isotopes has been studied via the shell model with SkyrmeHartreeFock calculations. In particular, the transitions to the lowlying positive and negative parity excited states have been investigated within three shell model spaces; sd for positive parity states, spsdpf largebasis (nocore), and zbme model spaces for negative parity states. Excitation energies, reduced transition probabilities, and elastic and inelastic form factors were estimated and compared to the available experimental data. Skyrme interaction was used to generate a onebody potential in the HartreeFock calculations for each selected excited states, which is then used to calculate the singleparticle matrix elements. Skyrme interaction was used to calculate the radial wave functions of the singleparticle matrix elements, from which a onebody potential in HartreeFock theory with SLy4 parametrization can be generated. Furthermore, we have explored the interplays among neutron and proton density profiles in two dimensions, along with the deformations of 20,22Ne using HartreeFock plus BCS calculations.
PubDate: 20230602
DOI: 10.26565/231243342023213
 Physicochemical Characteristics for Fen (n = 2–10) Cluster by
Density Functional Theory
Authors: Yamina Benkrima, Djamel Belfennache, Radhia Yekhlef, Mohammed Elbar Soudani, Abdelkader Souiga, Yahia Achour
Pages: 150  156
Abstract: The In this work, we present a theoretical study on the equilibrium geometry and the energetic, electronic and magnetic properties of Fen (n = 2–10) based on the use of density functional theory (DFT). The results are obtained using Both Generalized Gradient Approximation according to the scheme described by PerdewBurkeErnzerhof (GGAPBE). More stable structures obtained compared to other isomers have not been previously found. It is shown by the results calculated as the calculated fragmentation energy, and the secondorder energy difference that Fen (n = 7,8,9) clusters are more stable than the other cluster sizes. The calculated magnetic properties of the most stable clusters display varying magnetic torque between values 3.00 μB and 3.35 μB, except for the Fe10 cluster, which takes the upper value 3.38 μB. These results are very important for experimental experts who are active in designing new nanocatalysis systems in the physical and chemical fields.
PubDate: 20230602
DOI: 10.26565/231243342023214
 Effect of Si3N4/TaC nanomaterials on the structural and electrical
characteristics of poly methyl methacrylate for electrical and electronics
applications
Authors: Alaa Abass Mohammed, Majeed Ali Habeeb
Pages: 157  164
Abstract: In this study, the casting method was used to prepared PMMA/Si3N4/TaC nanocomposites with variant content (0,2,4,6,8) % wt of Si3N4/TaC nanoparticles. The structural and electrical properties have been investigated. Scanning electron microscope (SEM) indicate that the homogenous, smooth and dispersed of Si3N4 and TaC NPs inside the PMMA matrix due to strong covalent interaction between the Si3N4 and TaC NPs in the PMMA matrix which mean a good method for prepared films. Optical microscope images explained that when increasing in content of nanoparticles that forming network paths inside the polymeric matrix that act as charge carriers. FTIR spectra indicate to a physical interference between the polymer matrix and nanoparticles. The AC electrical properties of nanocomposites obtained that the dielectric constant and dielectric loss rise with rising content of nanoparticles and decrease with rising frequency of applied electric field. While the A.C electrical conductivity rise with rising the frequency and weight content of Si3N4/TaC nanoparticles. This results indicated that the PMMA/Si3N4/TaC nanostructures can be considered as promising materials for electronics and electrical nanodevices.
PubDate: 20230602
DOI: 10.26565/231243342023215
 Computation of Characteristics of C IV Transitions
Authors: Muhammad Saeed, Shafiq Ur Rehman, Mahwish Mobeen Khan, Zaheer Uddin
Pages: 165  172
Abstract: In this research, we computed transition probabilities, line strength, and oscillator strengths of more than 5000 transitions in C IV. Very few values of these spectroscopic characteristics were previously known and reported. The calculation method, based on a combination of the weakest bound electron model and numerical approximation, shows reliable values because the correlation between known and calculated values is high. The transition probabilities calculated in this work are compared with known values of the NIST database and those found in literature, and a reasonably good agreement has been observed. The lifetime of Rydberg levels ns, np, nd, nf, ng has been reported up to n = 25. A general sixthdegree polynomial was developed, generating C IV lifetimes with reasonable accuracy. Most of the results presented are new.
PubDate: 20230602
DOI: 10.26565/231243342023216
 Influence of Thickness on Some Physical Characterization for
Nanostructured MgO Thin Films
Authors: Muhammad H. AlTimimi, Widad H. Albanda, Mustafa Z. Abdullah
Pages: 173  181
Abstract: MgO Nanostructured thin films with different thicknesses (200, 400, and 600 nm) have been deposited by the chemical spray pyrolysis technique. The results confirm that the structure, morphology, optical, and electrical properties were all affected by the thickness of the film. MgO films' physical properties were examined using (XRD), (FESEM), (EDX), (AFM), (UVVis spectrophotometer), and the Hall Effect. According to the structural analysis, the films have a cubic magnesium oxide polycrystalline structure, with a preferred orientation (002). The average Crystalline Size and optical band gap are found in the range (20.7918.99) nm and (3.4393.162) eV respectively with an increase in thickness. The surface morphology of the films reveals that they are free of crystal defects such as holes and voids, as well as homogeneous and uniform. The EDS patterns show that the asgrown films contain magnesium and oxygen. The Hall Effect shows that electrical conductivity decreases with thickness. The experimental results show that film thickness influences the physical properties of asgrown MgO thin films and that thicker films can be used as an absorber layer in solar cell applications.
PubDate: 20230602
DOI: 10.26565/231243342023217
 The Thermoluminescence Parameters of Irradiated KFeldspar
Authors: Sahib Mammadov, Aybeniz Ahadova, Aqshin Abishov, Ahmad Ahadov
Pages: 182  186
Abstract: Isothermal decay of the TL glow curve has been studied at ambient temperature. Heating of feldspar at 600ºC leads to increased sensitivity of the samples upon irradiation for the whole range of glow curve. In general, we observe a sensitivity increase of about five times. Fading of the glow curve is observed at the lowtemperature part of the glow curve while it has been kept in the dark at the ambient, constant temperature. After a certain period, approximately in 40 to 50 days, the lowtemperature region of the glow curve fades down while the hightemperature part remains unchanged. Peaks at the lowtemperature region of the TL glow curve were isolated by the curve subtraction method. Activation energy and frequency factor parameters of the isolated peaks were calculated, taking first and secondorder kinetics into account. The values of the calculated activation energy vary between 0.7 to 1.1 eV, and frequency factor values of the isolated peaks change within the order of 109 to 1013s1. The µ values clearly indicate that all isolated peaks are more likely to be secondorder kinetics.
PubDate: 20230602
DOI: 10.26565/231243342023218
 Some Properties of SemiconductorFerroelectric Structures
Authors: Zakirjan T. Azamatov, Sharifa B. Utamuradova, Murodjon A. Yuldoshev, Nurlan N. Bazarbayev
Pages: 187  190
Abstract: This paper presents the properties of semiconductorferroelectric structures consisting of ZnO nanorods grown at low temperatures by the hydrothermal method on LiNbO3 and LiNbO3:Fe substrates. The resulting structures were analyzed by scanning electron microscope, photoluminescence, and spectrophotometry. SEM images and spectra, absorption spectra, and photoluminescence spectra in the ultraviolet and visible ranges are presented. The studies have shown the possibility of using, along with others, the hydrothermal method for synthesizing Zn(NO3)26H2O and C6H12N4 to obtain arrays of ZnO nanorods as a sensitive element of surfactantbased UV radiation sensors.
PubDate: 20230602
DOI: 10.26565/231243342023219
 Modeling the Distribution of Radionuclides in the Air and on the Soil
Surface
Authors: Maryna F. Коzhevnikova, Volodymyr V. Levenets
Pages: 191  200
Abstract: Mathematical and numerical methods are used to simulate physical and chemical processes when building models of pollutants dispersion in the air and on the soil surface. Based on meteorological data and information on the source of emissions, these models characterize both the primary pollutants entering the atmosphere directly and the secondary ones formed as the result of complex chemical reactions. These models are important for the air quality management system, as they allow monitoring emissions into the atmosphere, predicting their distribution, as well as developing effective strategies intended for reducing harmful substances in the atmosphere. The article presents an overview of computational methods used to simulate the pollutants dispersion in atmospheric air and on the soil surface, such as the Gaussian torch model, the Lagrangian dispersion stochastic model, and the Eulerian model of atmospheric diffusion. The practical application of the considered models showed sufficient reliability and validity of the air and soil pollution levels forecast. The simulation uses computer programs that include algorithms for solving the mathematical equations that control pollutant dispersion. The dispersion models are used to estimate the concentration of air pollutants or toxins. They can also be used to predict future concentrations under certain scenarios. They are useful for studying the pollutants that disperse over long distances and can initiate reactions in the atmosphere. Such software products are as follows: AEROPOL, AERMOD, GRAL, TAPM CSIRO, CALPUFF, HYSPLIT, etc. A method of processing information about the pollution sources and the environmental parameters, based on the HYSPLIT program, is proposed to form maps of the volume and surface activity of radionuclides. This method was applied to analyze the process of the plutonium isotopes dispersion as a result of the movement of air masses in the places of fires in April 2020 in the exclusion zone of the Chornobyl NPP, as well as the associated hazard for the population health and the environment.
PubDate: 20230602
DOI: 10.26565/231243342023220
 XRay Structural Investigations Of nSi
Irradiated with Protons
Authors: Sharifa B. Utamuradova, Aliona V. Stanchik, Dilmurod Rakhmanov
Pages: 201  205
Abstract: In this work, the effect of proton irradiation on the change in the structure of silicon samples doped with platinum was studied. The samples were irradiated with protons at a dose of 9×1014 cm2 with an energy of 600 keV and a current of 1÷1.5 μA. To determine the change in the structure after irradiation, the methods of Xray diffraction and atomic force microscopy were used. The obtained results indicate that doping with platinum does not lead to a modification of the cubic crystal structure of silicon, but only to minor changes in the structural characteristics and surface morphology. In this case, proton irradiation of a silicon single crystal with a dose of 9.0×1014 cm–2 with an energy of 600 keV leads to the formation of defects without the formation of an amorphous nearsurface layer.
PubDate: 20230602
DOI: 10.26565/231243342023221
 Improvement of the Shielding Effectiveness of PMMA/MWCNTs/Ag Hybrid
Composite for XBand Application
Authors: Badiaa Ismal Alawi, Nadia Abbas Ali
Pages: 206  214
Abstract: Herein, the PMMA/MWCNT/Ag hybrid composite films are prepared by solvent casting method to be used in an electrical application. The AC conductivity and dielectric characteristics have been investigated at room temperature. The electrical conductivity of the hybrid composite reaches a percolation critical concentration of 2.14×104 S/cm by Ag doping. For all PMMA/MWCNT/Ag hybrid composites, the frequencydependent dielectric constant decreases as the frequency area widens. As the concentrations of MWCNT and Ag increase, the AC conductivity exhibits an increasing trend. The MWCNT and Ag content was found to significantly affect the SE of the given composites. A high electromagnetic (EM) shielding efficiency (SE) was achieved between 8.2 and 12.4 GHz (Xband). The highest EM attenuation of 18 dB at 12 GHz was achieved using 0.5 wt% MWCNT and Ag. The thermal analysis of the formed PMMA/MWCNT/Ag hybrid composites showed that exothermic reactions with the greatest weight loss took place between 200°C and 300°C. FESEM show that PMMA/MWCNT/Ag hybrid composites had uniform dispersion of the carbon nano tube and silver particles within the PMMA matrix .
PubDate: 20230602
DOI: 10.26565/231243342023222
 Study of MgO Under Pressure Structural and Electronic Properties
Authors: Yamina Benkrima, Abderrahim Achouri, Djamel Belfennache, Radhia Yekhlef, Naim Hocine
Pages: 215  220
Abstract: In this study, the Density Function Theory (DFT), Generalized Gradient Approximation (GGA) and Local Density Approximation (LDA) were used, based on the Siesta code, in order to study the magnesium oxide compound (MgO) and focus on the (B4) Wurtzite phase. This is to find the primary cell constants and energy gap at 0 pressure, which are consistent with previous results. The effect of pressure on the energy gap and the size of the primary cell as well as the dielectric constant were studied. The study also revealed that the (B4) phase can move to the (B2) phase at the pressure of 45.86 GPa and from the hMgO phase to the (B2) phase at 70 GPa.
PubDate: 20230602
DOI: 10.26565/231243342023223
 Calculation of the Total Current Generated in a Tunnel Diode Under the
Action of Microwave and Magnetic Fields
Authors: Gafur Gulyamov, Sharifa B. Utamuradova, Mukhamadjon G. Dadamirzaev, Nozimjon A. Turgunov, Munira K. Uktamova, Kakhramon M. Fayzullaev, Arofat I. Khudayberdiyeva, Alisher I. Tursunov
Pages: 221  227
Abstract: In this paper, a formula was derived for calculating the total current generated in a tunnel diode under the action of a microwave field and a magnetic field. In addition, the dependence of the total current of the tunnel diode on the total power induced by the microwave field is theoretically presented and compared with experimental data. For the total current in the tunnel diode, without taking into account the excess current, voltampere characteristics was obtained for cases with and without the influence of a microwave field.
PubDate: 20230602
DOI: 10.26565/231243342023224
 Synthesis and Characterization of (PVACoOZrO2) Nanostructures for
Nanooptoelectronic Fields
Authors: Zainab Sabry Jaber, Majeed Ali Habeeb, Waleed Hadi Radi
Pages: 228  233
Abstract: Nanocomposites have a wide range of applications, including optical integrated circuits, sensors, coatings, and medical devices. As a result, the purpose of this paper is to prepare a new type of nanocomposites made of polyvinyl alcohol (PVA) with different concentrations (0, 1, 2 and 3) wt% of cobalt oxide and zirconium dioxide (CoOZrO2) nanoparticles by using casting method. Microscopic photographs demonstrate the fact that the additive distribution amount of NPs in the polymer was uniform, and (CoOZrO2) NPs formed a continuous network within the polymer when the concentration reached 3wt.%. The outcomes of optical properties indicate that the absorbance of nanocomposites improves as the concentrations of cobalt oxide and zirconium dioxide nanoparticles increase while transmittance and the optical energy gap decrease. On the other hand, optical constants of nanocomposites (refractive index, absorption coefficient, extinction coefficient, real and imaginary the dielectric constants) and optical conductivity are increase with increases in the weight percentages of (CoOZrO2) nanoparticles. These outcomes demonstrate the (PVACoO ZrO2) NCs use for various optical devices.
PubDate: 20230602
DOI: 10.26565/231243342023225
 Thermoelectric Properties Investigation of Ni/Co Doped ZrCoBi HalfHeusler
Alloy
Authors: Mahmoud AlElaimi
Pages: 234  240
Abstract: HalfHeusler (HH) thermoelectric (TE) composites have been extensively inspected due to their excellent TE properties in the medium to hightemperature range. Firstprinciple calculations make it easier to discover or improve more HH compounds. This article presents an ab initio theoretical evaluation of TE properties of HalfHeusler alloy, when doped with Nickel (Ni), using FPLAPW and the semi classic Boltzmann theory. Thermoelectric parameters were calculated using BoltzTraP code, like Seebeck coefficient ( ), electrical conductivity to relaxation time ratio ( ), electronic thermal conductivity to relaxation time ratio ( ), thermoelectric power factor to relaxation time ratio ( ), and the dimensionless figureofmerit ( ) in a temperature range of . Calculated Seebeck coefficient reveals that the studied alloys show a tendency to conduct as ptype with balanced TE performance between both charge carriers (holes and electrons). A high electronic thermal conductivity value is found, which predicts a potential use in heat sink applications for the investigated alloys. Obtained results, such as a high thermoelectric power factor and , postulate that alloys could have potential thermoelectric applications.
PubDate: 20230602
DOI: 10.26565/231243342023226
 Study of Fusion Reactions of Light Projectiles on Light and Medium Targets
Authors: Malik S. Mehemed
Pages: 241  248
Abstract: The fusion and breakup reactions of some light projectiles on light and medium targets using semiclassical and full quantum mechanical approaches were adopted to calculate the total cross section σfus and the distribution of the fusion barrier Dfus for the systems 12C + 48Ti, 16O+63Cu, 35Cl+25Mg and 35Cl+27Al. The coupling between the channel’s contribution from elastic and breakup channels were considered to show their importance in the calculations. The results compared with the measured data and shows reasonable matching, and it is shown that the coupling considered is very essential to be considered, especially below the Coulomb barrier Vb.
PubDate: 20230602
DOI: 10.26565/231243342023227
 The CZTS Thin Films Grown by Sulfurization of Electrodeposited Metallic
Precursors: The Effect of Increasing Tin Content of the Metallic
Precursors on the Structure, Morphology and Optical Properties of the Thin
Films
Authors: E.A. Botchway, Francis Kofi Ampong, Isaac Nkrumah, D.B. Puzer, Robert Kwame Nkum, Francis Boakye
Pages: 249  256
Abstract: A study has been carried out to investigate the influence of the amount of Sn in the precursor solution, on some physical properties of CZTS films grown by sulfurization of electrodeposited metallic precursors. The growth of the CZTS samples was achieved by sequential electrodepositon of constituent metallic layers on ITO glass substrates using a 3electrode electrochemical cell with graphite as a counter electrode and Ag/AgCl as the reference electrode. The Sncontent in the metallic precursor was varied by varying the deposition time of Sn. The stacked elemental layer was then soft annealed in Argon at 350 °C, and subsequently sulfurized at 550° C to grow the CZTS thin films. The structure, morphology and optical properties were investigated. Xray diffraction studies revealed that, irrespective of the Sn content all the films were polycrystalline and exhibited the Kesterite CZTS structure with preferred orientation along the (112) plane. However, there was an increase in the amount of peaks indexed to the undesirable secondary phases, as the Sn content in metallic precursor was increased. Optical absorption measurements revealed the existence of a direct transition with band gap values decreasing from 1.74 eV to 1.25 eV with increasing amounts of Sn. The lower value for the band gap was attributed to the presence of secondary phases formed in addition to the CZTS film. Morphology of the sulfurized films showed a compact and rocky texture with good coverage across the entire substrate. However, CZTS films with a higher Sn content appeared to have a molten metallic surface with deep cracks which could have adverse effects on the electrical properties of the film. EDAX analysis showed all the films were consistent with the formation of CZTS. It is evident from all the characterization techniques that increasing the Sn content of the stacked metallic precursors beyond stoichiometric amounts had an adverse effect on the structural and optical properties of CZTS films grown by this technique.
PubDate: 20230602
DOI: 10.26565/231243342023228
 MagnetoThermoelectric Coefficients of Heavily Doped NType Mg2Si Material
Authors: Mulugeta Habte Habte
Pages: 257  266
Abstract: In contrast to parabolic band model typically used in understanding electronic properties in general, thermoelectric and magnetothermoelectric in particular, this study confirms nonparabolic band model results in better understanding of Seebeck coefficient and Nernst coefficient in the presence of magnetic field for Mg2Si. The magneto Seebeck coefficient was found significantly enhanced from its zerofield value for different electron concentrations in the range 0.6 ‑ 12×1025/m3 and at room temperature due to the magnetic field in the range 0.2 – 1 T for nonparabolic model compared to parabolic band model. The result for Nernst coefficient shows increasing trend as function of magnetic field except for certain electron concentrations for parabolic band model while it is decreasing with magnetic field on average for nonparabolic band model.
PubDate: 20230602
DOI: 10.26565/231243342023229
 Experimental Simulation for Two Optically Filtered Modulation Weights in
Laser Diode as a SelfLearning Layer
Authors: Dhuha Raad Madhloom, Ayser A. Hemed, Suha Musa Khorsheed
Pages: 267  276
Abstract: In this study, the response of a nonlinear laser medium is experimentally studied. In the study, a hybrid version of the input layer that multiplies optically and accumulates electrically is compared with a wholly optical version that multiplies and accumulates optically. This medium is subjected to two different paths of optically filtered and attenuated feedback. With such a system, the variation of feedback weight in one of them is tested in correspondence to the second one. Observations for frequency spectra are carried out to simulate the resultant response with an input layer for a neural network based on chaotic carriers. Chaotic laser emission was observed as a function of several control parameters, which are D.C. bias voltage, branch optical attenuation, and feedback strengths based on filtration with fiber Bragg grating. This learning rule is linear in the difference between each input and output of a neuron. This is an enhancing/inhibiting rule. The thresholds are adjusted in such a way that the output of the neuron is either pushed in the same direction as the input (enhancing) or pushed in the opposite direction (inhibiting).
PubDate: 20230602
DOI: 10.26565/231243342023230
 Reevaluation Body Weight and Age with Standardized Uptake Value in the
Liver Cancer for [18F] FDG PET/CT
Authors: Aya B. Hade, Satar M. Kadam, Samar I. Essa
Pages: 277  281
Abstract: Standardized uptake values, often known as SUVs, are frequently utilized in the process of measuring 18Ffluorodeoxyglucose (FDG) uptake in malignancies . In this work, we investigated the relationships between a wide range of parameters and the standardized uptake values (SUV) found in the liver. Examinations with 18FFDG PET/CT were performed on a total of 59 patients who were suffering from liver cancer. We determined the SUV in the liver of patients who had a normal BMI (between 18.5 and 24.9) and a high BMI (above 30) obese. After adjusting each SUV based on the results of the body mass index (BMI) and body surface area (BSA) calculations, which were determined for each patient based on their height and weight. Under a variety of different circumstances, SUVs were evaluated based on their means and standard deviations. Scatterplots were created to illustrate the various weight and SUV variances. In addition to that, the SUVs that are appropriate for each age group were determined. SUVmax in the liver was statistical significantly in obese BMI and higher BSA, p value <0.001). Age appeared to be the most important predictor of SUVmax and was significantly associated with the liver SUVmax with mean value (58.93±13.57). Conclusions: Age is a factor that contributes to variations in the SUVs of the liver. These agerelated disparities in SUV have been elucidated as a result of our findings, which may help clinicians in doing more accurate assessments of malignancies. However, the SUV overestimates the metabolic activity of each and every individual, and this overestimation is far more severe in people who are obese compared to people who have a body mass index that is normal (BMI).
PubDate: 20230602
DOI: 10.26565/231243342023231
 The Effect of Diffuseness Parameter on the QuasiElastic Scattering of the
25Mg + 90Zr and 28Si + (120Sn ,150Nd) Systems using WoodSaxon Potential
Authors: Khalid S. Jassim, Farah J. Hamood
Pages: 282  288
Abstract: In this research, the effect of changing the values of the diffusion parameter on the semielastic scattering ( ) and distribution (D) calculations for (SC) and (CC) have been studied. Three values were taken from the diffusion for each system parameter. It is assumed that the nuclear potential has a WoodsSaxon form, which is indicated by the surface diffuseness, potential depth, and radius parameters for (25Mg + 90Zr), (28Si + (120Sn ,150Nd) Systems. The chisquare (χ2) is applied to compare the bestfitted value of the diffuseness parameter between the theoretical calculations and the experimental data. According to the results of (χ2 ), we noticed that some systems achieved a good match between the theoretical calculations and experimental data of semielastic scattering ( ) and the distribution calculations at the standard value of the diffusion parameter (a0=0.63 ) or at a value higher and lower than the standard value. In the case of (SC ) the best fit was at a value less than the standard value of the diffusivity parameter but in the case of (CC ), the fit was better at a value higher than the standard value of the diffusivity parameter because the potential barrier in the (SC ) is single, while in (CC ) calculations it is multiple.
PubDate: 20230602
DOI: 10.26565/231243342023232
 Problems of Masking and AntiReflective SiO2 in Silicon Technology
Authors: Mykola S. Kukurudziak
Pages: 289  295
Abstract: The article examines the problems of thermal oxidation of silicon. Oxidation plays an important role in planar technology, which in turn is the basis of the technology of silicon integrated circuits, photodetectors and other solidstate electronics. During our production of silicon pin photodiodes, a number of systematic types of defects and deterioration of product parameters caused by the degradation of masking or antireflective coatings during the manufacturing process were observed. A decrease in the insulation resistance of responsive elements in multielement photodiodes was observed, which contributed to the increase of dark currents. A decrease in the responsivity of the products due to the degradation of the thickness or structure of the antireflective coating during technological operations, etc., was also revealed. It was established that the reason for the decrease in insulation resistance is the formation of inversion layers at the SiSiO2 interface, the presence of which can be detected when measuring CVcharacteristics. It was also established that chemical treatment of substrates with SiO2 in boiling acid solutions helps to reduce the thickness of the oxide. To avoid deviation of the thickness of the film from the condition of minimum reflection, it is necessary to grow a thicker layer of antireflective coating. It is noted that when etching the oxide during photolithography or when removing the PSG/BSG in hydrofluoric acid, it is not permissible to remove the cassette with plates from the solution for a long time, as this leads to uneven etching of the film due to the flow of the herb on the surface of the substrate. The causes of defect formation in Si and SiO2 during oxidation are given. Thus, with improper mechanical and chemical processing of the plates, cristobalite inclusions may form in the film during oxidation. Cristobalite has a higher density than quartz glass, and the boundaries between amorphous regions and denser crystalline regions represent voids, which can be filled both by impurities from the surface and by the diffusant in the diffusion process. Also, during oxidation in silicon, packing defects are often formed. Centers of defect genesis can be mechanical damage to the plate surface or growth defects.
PubDate: 20230602
DOI: 10.26565/231243342023233
 Oscillatory Porous Medium Ferroconvection in a Viscoelastic Magnetic Fluid
with NonClassical Heat Conduction
Authors: Naseer Ahmed, S. Maruthamanikandan , B.R. Nagasmitha
Pages: 296  309
Abstract: The classical stability analysis is used to examine the combined effect of viscoelasticity and the second sound on the onset of porous medium ferroconvection. The fluid and solid matrix are assumed to be in local thermal equilibrium. Considering the boundary conditions appropriate for an analytical approach, the critical values pertaining to both stationary and oscillatory instabilities are obtained by means of the normal mode analysis. It is observed that the oscillatory mode of instability is preferred to the stationary mode of instability. It is shown that the oscillatory porous medium ferroconvection is advanced through the magnetic forces, nonlinearity in magnetization, stress relaxation due to viscoelasticity, and the second sound. On the other hand, it is observed that the presence of strain retardation and porous medium delays the onset of oscillatory porous medium ferroconvection. The dual nature of the Prandtl number on the Rayleigh number with respect to the Cattaneo number is also delineated. The effect of various parameters on the size of the convection cell and the frequency of oscillations is also discussed. This problem may have possible implications for technological applications wherein viscoelastic magnetic fluids are involved.
PubDate: 20230602
DOI: 10.26565/231243342023234
 Enhancement in Some Physical Properties of (PVP: CMC) Blend by the
addition of MgO
Authors: Widad H. Albanda, D.J. Fakralden, N.A. Hassan
Pages: 310  316
Abstract: This research study explores the effects of adding MgO nanoparticles to a polymeric blend composed of 50% PVP and 50% CMC. The blend was prepared using MgO nanoparticles (0.2%, 4%, and 6%) and varying processing conditions. The structural, optical, and electrical properties of the resulting blend were analyzed to determine the impact of the added nanoparticles on the blend's properties. Results showed that the addition of nanoparticles significantly improved the structural, optical, and electrical properties of the polymeric blend. Specifically, the energy gap is 4.224 eV for (PVA: CMC) film and increased to 3.432 eV for (PVA: CMC6% MgO), the light transmission and reflection properties were enhanced. Additionally, the conductivity of the blend was increased, making it suitable for various applications, including optoelectronics, sensors, and biomedical devices. Overall, this study demonstrates the potential of adding nanoparticles to polymeric blends to improve their properties and highlights the importance of optimizing processing conditions to achieve the desired properties for specific applications.
PubDate: 20230602
DOI: 10.26565/231243342023235
 The Magnetic Form Factors for Some Nuclei 51V, 59Co, 93Nb, 115In by using
Valence with and Without Core Polarization Effects Models
Authors: Sajad A. Khasain, Khalid S. Jassim
Pages: 317  323
Abstract: The magnetic electron scattering form factor with glekpn, d3f7, ho models space for 51V , 59Co, 93Nb, and 115In nuclei are discussed with and without core polarization effects(CP). The calculations are done with the help of NuShellX@MUS code. The radial wave function for the singleparticle matrix elements have been calculated with the SKyrmeHartree Fock (SKX), WoodSaxon(WS), and harmonic oscillator (HO) potentials. valence model(Vm) used in these calculation to calculate form factors with corepolarization effects. The results give a good agreement with available experimental data.
PubDate: 20230602
DOI: 10.26565/231243342023236
 Isoscalar Giant Octupole Resonance ISGOR of 116Cd using SelfConsistent
Skyrme QRPA
Authors: Maryam A. Akbar, Ali H. Taqi
Pages: 324  328
Abstract: Collective models based on the random phase approximation (RPA) are widely used to accurately depict collective modes of response. They can quickly calculate the strength function for the entire nuclear mass range. The quasiparticle random phase approximation (QRPA), which considers the pairing effect, is an enhanced RPA model. It is anticipated that this effect will be significant for openshell nuclei. In this work, the selfconsistent Skyrme HartreeFockBardeen, Cooper, and Schrieffer (HFBCS) and QRPA models have been used to study the isoscalar giant octupole resonance (ISGOR) in the 116Cd isotope. Ten Skyrmetype parameters are utilized in the computations since they may be identified by different values of the incompressibility modulus KMN in nuclear matter. The calculated strength distributions and centroid energy are compared with available experimental data. We saw that the strength distributions varied depending on the type of Skyrmeinteraction, and we also observed a definite impact of the KNM values on the centroid energy.
PubDate: 20230602
DOI: 10.26565/231243342023237
 HoleHole Collective Excitations in 106, 112, 130Sn Isotopes
Authors: Fahima A. Saber, Ali H. Taqi
Pages: 329  334
Abstract: In this paper, energylevel schemes of neutron rich and reduced electric transition strengths of Tin isotopes 106Sn, 112Sn and 130Sn were studied using collective models, i.e., holehole TammDancoff Approximation (hh TDA) and holehole Random Phase Approximation (hh RPA). According to these models, the excited states of closed core A2 systems with multipolarity J and isospin T can be described as a linear combination of holehole (hh) pairs. Therefore, in our approach, the lowlying states of the investigated isotopes 106Sn, 112Sn and 130Sn are obtained by acting twohole operators on a correlated core 108Sn, 114Sn and 132Sn, respectively. The Hamiltonian is diagonalized within the model space include {1g7/2, 2d5/2, 2d3/2, 3s1/2 and 1h11/2} orbits, using the matrix elements of neutronneutron (NN) interaction and modified surface delta interaction (MSDI). The hh TDA and hh RPA are checked by using the resultant eigenvalues and eigenvectors to calculate the excitation energies and reduced electric transition strengths. A comparison had been made between our theoretical predictions and the recent available experimental data. Reasonable agreements were obtained from these comparisons.
PubDate: 20230602
DOI: 10.26565/231243342023238
 Molecular Docking Study of the Interactions Between Cyanine Dyes And DNA
Authors: Olga Zhytniakivska, Uliana Tarabara, Pylyp Kuznietsov, Kateryna Vus, Valeriya Trusova, Galyna Gorbenko
Pages: 335  340
Abstract: Among the various fluorescent probes currently used for biomedical and biochemical studies, significant attention attracts cyanine dyes possessing advantageous properties upon their complexation with biomolecules, particularly nucleic acids. Given the wide range of cyanine applications in DNA studies, a better understanding of their binding mode and intermolecular interactions governing dyeDNA complexation would facilitate the synthesis of new molecular probes of the cyanine family with optimized properties and would be led to the development of new cyaninebased strategies for nucleic acid detection and characterization. In the present study molecular docking techniques have been employed to evaluate the mode of interaction between one representative of monomethines (AK1217), three trimethines (AK31, AK33, AK35), three pentamethines (AK51, AK53, AK59) and one heptamethine (AK76) cyanine dyes and B–DNA dodecamer d(CGCGAATTCGCG)2 (PDB ID: 1BNA). The molecular docking studies indicate that: i) all cyanines under study (excepting AK59 and AK76) form the most stable dyeDNA complexes with the minor groove of doublestranded DNA; ii) cyanines AK59 and AK76 interact with the major groove of the DNA on the basis of their more extended structure and higher lipophilicity in comparison with other dyes; iii) cyanine dye binding is governed by the hydrophobic and Van der Waals interactions presumably with the nucleotide residues C9A, G10A (excepts AK31, AK35), A17B (excepts AK35, AK53) and A18B in the minor groove and the major groove residues С16B, A17B, A18B, C3A, G4A, A5A, A6A (AK59 and AK76); iv) all dyes under study (except AK31, AK35 and AK539 possess an affinity to adenine and cytosine residues, whereas AK31, AK35 and AK53 also interact with thymine residues of the doublestranded DNA.
PubDate: 20230602
DOI: 10.26565/231243342023239
 Improvement structural and dielectric properties of PS/SiC/Sb2O3
nanostructures for nanoelectronics devices
Authors: Majeed Ali Habeeb, Nawras Karim AlSharifi
Pages: 341  347
Abstract: In the current study, the PS/SiC/Sb2O3 nanocomposites have been prepared by using solution casting method with different concentrations of SiC/Sb2O3 nanoparticles (0,2,4,6,8) % wt. The structural and dielectric properties of (PS/SiC/Sb2O3) nanocomposites have been investigated. Full emission scanning electron microscope (FESEM) used to study the surface of nanocomposite. FESEM confirmed that good distribution of SiC and Sb2O3 NPs into the polymer matrix. Optical microscope (OM) was tested the morphological of nanocomposite that proven that the polystyrene is exceptionally miscible, as seen by its finer form and smooth, homogeneous surface, while the additive concentration SiC and Sb2O3 NPs are well distributed on the surface of the polymer nanocomposite films. Fourier transformation spectroscopy (FTIR) was examine the structural of nanocomposite and give the information of the vibration of molecules. From FTIR, the additive SiC and Sb2O3 NPs caused interaction with polymer matrix. FTIR proven that there is physical interactions between polystyrene and SiC and Sb2O3 NPs. According to AC electrical properties, dielectric constant and dielectric loss of the NCs reduce with increasing the frequency of the applied electric field and increased with increasing concentration of SiC/Sb2O3 nanoparticles, while AC electrical conductivity increased with increasing frequency and concentration of SiC/Sb2O3 NPs. The results of structural and electrical characteristics show that the PS/SiC/Sb2O3 nanocomposites may be used for various electronics devices.
PubDate: 20230602
DOI: 10.26565/231243342023240
 Bottomonia Under Effect Three Inspired QCD Potentials in the Framework of
NonRelativistic Quark Model
Authors: Moustafa Ismail Hapareer, M. Allosh, G.S. Hassan, A.M. Yasser
Pages: 348  358
Abstract: In this paper, we have studied the spectrum of bottomonium mesons behavior under the effect of three types of potentials inspired by Quantum Chromodynamics. In addition, other properties like Hyperfine splitting behavior, and Fine splitting behavior have been studied. We used these potential models within the nonrelativistic quark model to present this study. We found that our expectations are consistent with experimental data and other theoretical works as well we presented new conclusions regarding the spectrum of unseen bottomonium states for S, P, and Dwave bottomonia. And we have expected other their characteristics.
PubDate: 20230602
DOI: 10.26565/231243342023241
 Bioconvection Effects on NonNewtonian Chemically Reacting Williamson
Nanofluid Flow Due to Stretched Sheet With Heat and Mass Transfer
Authors: Muhammad Jawad, M. MutiUrRehman, Kottakkaran Sooppy Nisar
Pages: 359  369
Abstract: The aim of this paper is to scrutinize the mixed convective flow of Williamson nanofluid in the presence of stretched surface with various physical effects. The impact of Brownian motion and thermophoresis is the part of this investigation. In addition, the features of thermal radiations is considered in energy equation for motivation of problem. Theory of the microorganism is used to stable the model. Mathematical modelling is carried out. Appropriate similarity functions are used to transform the couple of governing PDEs into set of ODEs. Wolfram MATHEMATICA is engaged to solve transformed equations numerically with the help of shooting scheme. The influence of emerging flow parameters like magnetic, thermophoresis, porosity, Péclet and Lewis number on the velocity, temperature, volumetric concentration and density of microorganism distribution are presented in tables and graphs.
PubDate: 20230602
DOI: 10.26565/231243342023242
 The Effect of Gas Flow Rate, Exposure Times and Ageing on the
Physicochemical Properties of Water Activated by Glow Discharge Plasma Jet
Authors: Farah A. Naeim, Hammad R. Humud
Pages: 370  377
Abstract: The goal of this work is to look into how the glow discharge plasma jet system changes the chemical and physical features of water. In this work, the physical and chemical properties of water were studied by using a plasma jet with Argon gas. 10 cm3 of distilled water was put in a glass dish with a diameter of 5 cm and a depth of 1 cm. The system was run with an AC voltage of 12 kV and a frequency of 20 kHz, and the exposure time ranged from 1 to 30 minutes. With amounts of 0.7, 1.0, 1.5, and 2.1 l/min, kits made by the American company Bartvation were used to measure the types of reactive oxygen and nitrogen species (RONS) that were formed. The data showed that the levels of NO2, NO3, and H2O2 were all too high. It gets bigger over time and as the flow rate goes up. The pH goes down with time until it hits 3, and the temperature goes up until it reaches 33°C. However, the pH goes up with storage time, and after 24 hours the water is back to its natural pH of 7. The amount of NO2, NO3, in the air goes up a little bit, and then starts to go down rapidly after 6 hours. After 24 hours, it is close to zero. From this, it's clear that the glow discharge plasma jet device can make RONS, which can be used for biological purposes.
PubDate: 20230602
DOI: 10.26565/231243342023243
 Exciton XRay Induced Luminescence of Y2O3 Polycrystals Sintered from the
Nanopowder
Authors: Evgen Barannik, Sergiy Kononenko, Vitaliy Zhurenko, Oganes Kalantaryan, Pylyp Kuznietsov
Pages: 378  383
Abstract: The paper is devoted to the changes in the Xray luminescence spectra of nanoscale Y2O3 ceramics, namely the radiation associated with a selftrapped exciton. Additional heat treatment (annealing) of ceramic samples leads to changes in the exciton band of the spectra. These are a change in the shape and shift of the maximum of this band. Longterm irradiation of the samples by Xray photons with an energy of 60 keV also led to changes in the exciton band. A theoretical model based on experimental data explains the changes in the spectra. The energy source of luminescence in this case is photoelectrons formed by energetic photons. Traps for these electrons are formed on the surface of submicrocrystals. Changes in the surfacetovolume ratio of crystals, as well as the frequencies of excited phonons and excitons are the basis for changes in the Xray luminescence spectra of Y2O3 ceramics.
PubDate: 20230602
DOI: 10.26565/231243342023244