East European Journal of Physics

Vortex Dynamo in Rotating Media

Michael I. Kopp — 2023-06-02

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 temperature-stratified 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 non-spiral 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.

Numerical Analysis on MHD mixed convection flow of Al_2O_3/H_2O (Aluminum-Water) Nanofluids in a Vertical Square Duct

Bishnu Ram Das — 2023-06-02

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.

Composite Fermions QED Lagrangian Density in Fractional Formulation

Amer D. Al-Oqali — 2023-06-02

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 Euler-Lagrange 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.

Theoretical Description of even- even Platinum Pt-186 nucleus using IBM and (VMI) Models

Ali K. Aobaid — 2023-06-02

The aim of this study, is to investigate, in a phenomenological way, the backbending effect in platinum Pt-186 nucleus, in order to get a good description of the bends by using new parameters. VMI model and interacting boson model IBM-1 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 Pt-186 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 VMI-model. Variable moment of inertia has been applied to describe successfully the effect of backbending in deformed even-even Pt-186 nucleus. Backbending was observed in the ground and β-bands, due to the change of the moment of inertia but not for (γ₁, γ₂ bands, because no changing in the moment of inertia.

A Study of the Weakly Bound Structure of Nuclei Around the Magic Number N=50

Ruwaida S. Obaid — 2023-06-02

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 2d_5/2in 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.

Describe of Nuclear Structure for Germanium (_32^66)Ge_34) Nucleus under frame (IBM-1, GVMI and VMI) Models

Imad A. Hamdi — 2023-06-02

In this paper, the interacting bosons model-1 (IBM-1), 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 even-even (_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.

Shell Model Investigation of Some p and sd-Shell Nuclei with Harmonic Oscillator and Skyrme Interactions

Sarah M. Obaid — 2023-06-02

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 one-particle, one-hole 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. Bohr-Mottelson 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 one-particle, one-hole 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.

Dual Solutions of Hybrid Nanofluid Flow Over a Cone with the Influence of Thermal Radiation and Chemical Reaction and Its Stability Analysis

Debasish Dey — 2023-06-02

The main intention of this study is to differentiate the stable and realisable solutions between the dual solutions of the water-based 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 built-in 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 time-independent 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.

Numerical Solution of Radiative Boundary Layer Flow in Porous Medium Due to Exponentially Shrinking Permeable Sheet Under Fuzzy Environment

Amir Barhoi — 2023-06-02

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=μc_p/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.

Involving Nikiforov-Uvarov Method in Schrodinger Equation Obtaining Hartmann Potential

Mahmoud A. Al-Hawamdeh — 2023-06-02

The total wave function and the bound state energy are investigated by involving the Nikiforov-Uvarov method to the Schrodinger equation in spherical coordinates employing Hartmann Potential (HP). The HP is considered as the non-central 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.

On Accounting for Own Fields of Emitters when Describing Generation Modes

Volodymyr M. Kuklin — 2023-06-02

The paper discusses three different modes of electromagnetic field generation by an ensemble of oscillators placed at the radiation wavelength in the one-dimensional 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 self-fields 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.

Determination of Band Structure and Compton profiles for Aluminum-Arsenide Using Density Functional Theory

Sameen F. Mohammed — 2023-06-02

First-principles computations of the electrical characteristics of AlAs have been carried out using the density functional theory-DFT and the Local Density Approximation-LDA,methods (DFT) and Generalized Gradient Approximation-GGA. 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 band-gap 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 free-atom 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.

Electroexcitation Form Factors and Deformation of 20,22Ne Isotopes Based on the Shell Model and Hartree-Fock plus BCS Calculations

Omar A. Alswaidawi — 2023-06-02

Nuclear structure of ^20,22Ne isotopes has been studied via the shell model with Skyrme-Hartree-Fock calculations. In particular, the transitions to the low-lying positive and negative parity excited states have been investigated within three shell model spaces; sd for positive parity states, spsdpf large-basis (no-core), 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 one-body potential in the Hartree-Fock calculations for each selected excited states, which is then used to calculate the single-particle matrix elements. Skyrme interaction was used to calculate the radial wave functions of the single-particle matrix elements, from which a one-body potential in Hartree-Fock 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 Hartree-Fock plus BCS calculations.

Physicochemical Characteristics for Fen (n = 2–10) Cluster by Density Functional Theory

Yamina Benkrima — 2023-06-02

The In this work, we present a theoretical study on the equilibrium geometry and the energetic, electronic and magnetic properties of Fe_n (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 Perdew-Burke-Ernzerhof (GGA-PBE). 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 second-order energy difference that Fe_n (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 μ_B and 3.35 μ_B, except for the Fe₁₀ cluster, which takes the upper value 3.38 μ_B. These results are very important for experimental experts who are active in designing new nanocatalysis systems in the physical and chemical fields.

Effect of Si3N4/TaC nanomaterials on the structural and electrical characteristics of poly methyl methacrylate for electrical and electronics applications

Alaa Abass Mohammed — 2023-06-02

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 Si₃N₄and TaC NPs inside the PMMA matrix due to strong covalent interaction between the Si₃N₄and 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.

Computation of Characteristics of C IV Transitions

Muhammad Saeed — 2023-06-02

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 sixth-degree polynomial was developed, generating C IV lifetimes with reasonable accuracy. Most of the results presented are new.

Influence of Thickness on Some Physical Characterization for Nanostructured MgO Thin Films

Muhammad H. Al-Timimi — 2023-06-02

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), (FE-SEM), (EDX), (AFM), (UV-Vis 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 (20.79-18.99) nm and (3.439-3.162) 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 as-grown 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 as-grown MgO thin films and that thicker films can be used as an absorber layer in solar cell applications.

The Thermoluminescence Parameters of Irradiated K-Feldspar

Sahib Mammadov — 2023-06-02

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 low-temperature 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 low-temperature region of the glow curve fades down while the high-temperature part remains unchanged. Peaks at the low-temperature 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 second-order 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 10¹³s^-1. The µ values clearly indicate that all isolated peaks are more likely to be second-order kinetics.

Some Properties of Semiconductor-Ferroelectric Structures

Zakirjan T. Azamatov — 2023-06-02

This paper presents the properties of semiconductor-ferroelectric 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 surfactant-based UV radiation sensors.

Modeling the Distribution of Radionuclides in the Air and on the Soil Surface

Maryna F. Коzhevnikova — 2023-06-02

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.

X-Ray Structural Investigations Of n-Si Irradiated with Protons

Sharifa B. Utamuradova — 2023-06-02

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 cm^-2 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 X-ray 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 near-surface layer.

Improvement of the Shielding Effectiveness of PMMA/MWCNTs/Ag Hybrid Composite for X-Band Application

Badiaa Ismal Alawi — 2023-06-02

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 2.14×10^-4 S/cm by Ag doping. For all PMMA/MWCNT/Ag hybrid composites, the frequency-dependent 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 (X-band). 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 .

Study of MgO Under Pressure Structural and Electronic Properties

Yamina Benkrima — 2023-06-02

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 h-MgO phase to the (B2) phase at 70 GPa.

Calculation of the Total Current Generated in a Tunnel Diode Under the Action of Microwave and Magnetic Fields

Gafur Gulyamov — 2023-06-02

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, volt-ampere characteristics was obtained for cases with and without the influence of a microwave field.

Synthesis and Characterization of (PVA-CoO-ZrO2) Nanostructures for Nanooptoelectronic Fields

Zainab Sabry Jaber — 2023-06-02

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 (CoO-ZrO₂) nanoparticles by using casting method. Microscopic photographs demonstrate the fact that the additive distribution amount of NPs in the polymer was uniform, and (CoO-ZrO₂) 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 (CoO-ZrO₂) nanoparticles. These outcomes demonstrate the (PVA-CoO -ZrO₂) NCs use for various optical devices.

Thermoelectric Properties Investigation of Ni/Co Doped ZrCoBi Half-Heusler Alloy

Mahmoud Al-Elaimi — 2023-06-02

Half-Heusler (HH) thermoelectric (TE) composites have been extensively inspected due to their excellent TE properties in the medium- to high-temperature range. First-principle calculations make it easier to discover or improve more HH compounds. This article presents an ab initio theoretical evaluation of TE properties of Half-Heusler alloy, when doped with Nickel (Ni), using FP-LAPW 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 figure-of-merit ( ) in a temperature range of . Calculated Seebeck coefficient reveals that the studied alloys show a tendency to conduct as p-type 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.

Study of Fusion Reactions of Light Projectiles on Light and Medium Targets

Malik S. Mehemed — 2023-06-02

The fusion and breakup reactions of some light projectiles on light and medium targets using semi-classical and full quantum mechanical approaches were adopted to calculate the total cross section σ_fus and the distribution of the fusion barrier D_fus 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 V_b.

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

E.A. Botchway — 2023-06-02

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 3-electrode electrochemical cell with graphite as a counter electrode and Ag/AgCl as the reference electrode. The Sn-content 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. X-ray 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.

Magneto-Thermoelectric Coefficients of Heavily Doped N-Type Mg2Si Material

Mulugeta Habte Habte — 2023-06-02

In contrast to parabolic band model typically used in understanding electronic properties in general, thermoelectric and magneto-thermoelectric in particular, this study confirms non-parabolic 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 zero-field 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 non-parabolic 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 non-parabolic band model.

Experimental Simulation for Two Optically Filtered Modulation Weights in Laser Diode as a Self-Learning Layer

Dhuha Raad Madhloom — 2023-06-02

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).

Reevaluation Body Weight and Age with Standardized Uptake Value in the Liver Cancer for [18F] FDG PET/CT

Aya B. Hade — 2023-06-02

Standardized uptake values, often known as SUVs, are frequently utilized in the process of measuring 18F-fluorodeoxyglucose (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 18F-FDG 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 age-related 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).

The Effect of Diffuseness Parameter on the Quasi-Elastic Scattering of the 25Mg + 90Zr and 28Si + (120Sn ,150Nd) Systems using Wood-Saxon Potential

Khalid S. Jassim — 2023-06-02

In this research, the effect of changing the values of the diffusion parameter on the semi-elastic 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 Woods-Saxon form, which is indicated by the surface diffuseness, potential depth, and radius parameters for (²⁵Mg + ⁹⁰Zr), (²⁸Si + (¹²⁰Sn ,¹⁵⁰Nd) Systems. The chi-square (χ²) is applied to compare the best-fitted 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 semi-elastic 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.

Problems of Masking and Anti-Reflective SiO2 in Silicon Technology

Mykola S. Kukurudziak — 2023-06-02

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 solid-state electronics. During our production of silicon p-i-n photodiodes, a number of systematic types of defects and deterioration of product parameters caused by the degradation of masking or anti-reflective coatings during the manufacturing process were observed. A decrease in the insulation resistance of responsive elements in multi-element 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 anti-reflective 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 Si-SiO₂ interface, the presence of which can be detected when measuring CV-characteristics. 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 anti-reflective 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.

Oscillatory Porous Medium Ferroconvection in a Viscoelastic Magnetic Fluid with Non-Classical Heat Conduction

Naseer Ahmed — 2023-06-02

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.

Enhancement in Some Physical Properties of (PVP: CMC) Blend by the addition of MgO

Widad H. Albanda — 2023-06-02

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: CMC-6% 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.

The Magnetic Form Factors for Some Nuclei 51V, 59Co, 93Nb, 115In by using Valence with and Without Core Polarization Effects Models

Sajad A. Khasain — 2023-06-02

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 single-particle matrix elements have been calculated with the SKyrme-Hartree Fock (SKX), Wood-Saxon(WS), and harmonic oscillator (HO) potentials. valence model(Vm) used in these calculation to calculate form factors with core-polarization effects. The results give a good agreement with available experimental data.

Isoscalar Giant Octupole Resonance ISGOR of 116Cd using Self-Consistent Skyrme QRPA

Maryam A. Akbar — 2023-06-02

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 quasi-particle random phase approximation (QRPA), which considers the pairing effect, is an enhanced RPA model. It is anticipated that this effect will be significant for open-shell nuclei. In this work, the self-consistent Skyrme Hartree-Fock-Bardeen, Cooper, and Schrieffer (HF-BCS) and QRPA models have been used to study the isoscalar giant octupole resonance (ISGOR) in the ¹¹⁶Cd isotope. Ten Skyrme-type parameters are utilized in the computations since they may be identified by different values of the incompressibility modulus K_MN 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 Skyrme-interaction, and we also observed a definite impact of the K_NM values on the centroid energy.

Hole-Hole Collective Excitations in 106, 112, 130Sn Isotopes

Fahima A. Saber — 2023-06-02

In this paper, energy-level schemes of neutron rich and reduced electric transition strengths of Tin isotopes ¹⁰⁶Sn, ¹¹²Sn and ¹³⁰Sn were studied using collective models, i.e., hole-hole Tamm-Dancoff Approximation (hh TDA) and hole-hole Random Phase Approximation (hh RPA). According to these models, the excited states of closed core A-2 systems with multipolarity J and isospin T can be described as a linear combination of hole-hole (hh) pairs. Therefore, in our approach, the low-lying states of the investigated isotopes ¹⁰⁶Sn, ¹¹²Sn and ¹³⁰Sn are obtained by acting two-hole operators on a correlated core ¹⁰⁸Sn, ¹¹⁴Sn and ¹³²Sn, respectively. The Hamiltonian is diagonalized within the model space include {1g_7/2, 2d_5/2, 2d_3/2, 3s_1/2 and 1h_11/2} orbits, using the matrix elements of neutron-neutron (N-N) 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.

Molecular Docking Study of the Interactions Between Cyanine Dyes And DNA

Olga Zhytniakivska — 2023-06-02

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 dye-DNA 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 cyanine-based 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 (AK12-17), three trimethines (AK3-1, AK3-3, AK3-5), three pentamethines (AK5-1, AK5-3, AK5-9) and one heptamethine (AK7-6) cyanine dyes and B–DNA dodecamer d(CGCGAATTCGCG)2 (PDB ID: 1BNA). The molecular docking studies indicate that: i) all cyanines under study (excepting AK5-9 and AK7-6) form the most stable dye-DNA complexes with the minor groove of double-stranded DNA; ii) cyanines AK5-9 and AK7-6 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 AK3-1, AK3-5), A17B (excepts AK3-5, AK5-3) and A18B in the minor groove and the major groove residues С16B, A17B, A18B, C3A, G4A, A5A, A6A (AK5-9 and AK7-6); iv) all dyes under study (except AK3-1, AK3-5 and AK5-39 possess an affinity to adenine and cytosine residues, whereas AK3-1, AK3-5 and AK5-3 also interact with thymine residues of the double-stranded DNA.

Improvement structural and dielectric properties of PS/SiC/Sb2O3 nanostructures for nanoelectronics devices

Majeed Ali Habeeb — 2023-06-02

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 (FE-SEM) used to study the surface of nanocomposite. FE-SEM confirmed that good distribution of SiC and Sb₂O₃NPs 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 Sb₂O₃NPs 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.

Bottomonia Under Effect Three Inspired QCD Potentials in the Framework of Non-Relativistic Quark Model

Moustafa Ismail Hapareer — 2023-06-02

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 non-relativistic 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 D-wave bottomonia. And we have expected other their characteristics.

Bioconvection Effects on Non-Newtonian Chemically Reacting Williamson Nanofluid Flow Due to Stretched Sheet With Heat and Mass Transfer

Muhammad Jawad — 2023-06-02

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.

The Effect of Gas Flow Rate, Exposure Times and Ageing on the Physicochemical Properties of Water Activated by Glow Discharge Plasma Jet

Farah A. Naeim — 2023-06-02

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.

Exciton X-Ray Induced Luminescence of Y2O3 Polycrystals Sintered from the Nanopowder

Evgen Barannik — 2023-06-02

The paper is devoted to the changes in the X-ray luminescence spectra of nanoscale Y₂O₃ ceramics, namely the radiation associated with a self-trapped 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. Long-term irradiation of the samples by X-ray 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 surface-to-volume ratio of crystals, as well as the frequencies of excited phonons and excitons are the basis for changes in the X-ray luminescence spectra of Y₂O₃ ceramics.