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Neoproterozoic U-Th-REE-bearing Pegmatites in Wadi Ibib, south Eastern Desert, Egypt: structural and Geochemical Measures for a syn-Tectonic Anatectic Model of Formation

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Acta Geologica sinica(English Edition) 2021年第6期95卷 2045-2062页

作者： Waleed s.ibrahim Nuclear Materials Authority El MaadiCairoEgypt

The Wadi Ibib area is situated in the northern part of the Neoproterozoic hamisana shear Zone(hsZ), which is a high strain zone evolved during the late stages of the Pan-African orogeny, likely as a tectonic escape structure. Amphibolite facies pelitic metasedimentary windows crop out in the axial parts of the hsZ and are noticeably associated with numerous N-trending pegmatite dikes. Whole-rock geochemistry of the pegmatites reveals a peraluminous(s-type) affinity, with low K/Rb ratios and elevated concentrations of U, Th, REE, Rb, Li, Cs, Y, Nb and Ta. structurally, the pegmatite sets intrude along the shear plane of the hsZ, corresponding to the regional N-trending tectonic fabrics, such as axial planar foliation and dextral-shearing in the metasedimentary host rock. Field relationships, including structural context, coupled with geochemical characteristics of the Wadi Ibib pegmatites, do not support their formation as a complementary part of evolved granitic magmas. space-localized decompression-induced partial melting of peraluminous garnet-bearing metapelites was alternatively the underlying process for formation of these pegmatites. such decompression was associated with regional escape tectonics and stress axes permutations during the late deformation stage(D3) in the evolution of the south Eastern Desert terrane, due to end-orogeny system pressure-release.

关键词： U-Th-REE mineralization anataxis pegmatite origin hamisana shear Zone Wadi Ibib Egypt

Magnetic properties of La2CuMnO6 double perovskite ceramic investigated by Monte Carlo simulations

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Chinese Physics B 2020年第5期29卷 387-391页

作者： s Mtougui I el housni N el Mekkaoui s Ziti s Idrissi h Labrim R Khalladi L Bahmad Laboratoire de la Matière Condensée et des sciences Interdisciplinaires (LaMCscI) Mohammed V University of RabatFaculty of SciencesB.P.1014 RabatMorocco Intelligent Processing and security systems Mohammed V University of RabatFaculty of SciencesB.P.1014 RabatMorocco UsM/DERs/Centre National de l’Energie des Sciences et des Techniques Nucl´eaires(CNESTEN)RabatMorocco

We present a theoretical study of the magnetic properties of the lanthanum copper manganate double perovskite La2CuMnO6 ceramic,using Monte Carlo *** analyze and discuss the ground state phase diagrams in different planes to show the effect of every physical *** on the Monte Carlo simulations,which combine Metropolis algorithm and Ising model,we explore the thermal behavior of the total magnetization and *** also present and discuss the influence of physical parameters such as the external magnetic field,the exchange coupling interactions between magnetic atoms,and the exchange magnetic field on the magnetization of the ***,the critical temperature of the system is about Tc=70 K,in agreement with the experimental ***,the hysteresis loops of La2CuMnO6 are discussed.

关键词： double perovskite La2CuMnO6 Monte Carlo simulations Ising model hysteresis loops Metropolis algorithm critical temperature

Evaluation of Al and some of Its Alloys as Anode Materials vs γ-MnO_2 as Cathode Material and Ore Produced γ-MnO_2 vs Zn Anode in KOh solution

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Journal of Materials science & Technology 2006年第1期22卷 25-30页

作者： A.M.A.hashem Kh.s.Abou-el-sherbini s.Zein el Abedin h.Abbas Inorganic Chemistry Department National Research CentreBehoes StreetDokkiCairoEgypt Physical Chemistry Department National Research CentreBehoes StreetDokkiCairoEgypt

In this study electrochemical performance of Al and some of its alloys （Al-Zn, Al-rvlg and Al-rvln） anodes vs MnO2 cathode were carried out in alkaline solution. The results show that the Al-Zn alloy anode has the best cell capacity among the other alloys. Cell capacity values go in the order Al-Zn〉Al-Mg〉Al〉Al-Mn. This result is probably related to the nature of passive films formed on the surface of the alloys which examined by scanning electron microscopy （sEM）. sEM morphologies of Al and its alloys showed coarse grains of passive films formed on the surface of these anode materials while Al-Mn morphology shows a needle-like structure. electrolytic manganese dioxide （EMD） produced by electrodepositing on platinum anode from liquor resulting from reduction of low grade pyrolusite ore （β-MnO2） by sulfur slag was characterized as cathode in alkaline Zn-MnO2 batteries. Ore produced sample （EMD1） was performed well in comparison with EMD standard （EMD2）（commercial battery grade electrolytic manganese dioxide, TOsOh-hellas Gh-s）. sEM morphology of Zn anode after cell reaction was carried out and showed that Zn anode has fine grains of passive film on its surface.

关键词： electrolytic MnO2 Zn Al Alkaline batteries

Improved Prediction of Metamaterial Antenna Bandwidth Using Adaptive Optimization of LsTM

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Computers, Materials & Continua 2022年第10期73卷 865-881页

作者： Doaa sami Khafaga Amel Ali Alhussan el-s.yed M.el-kenawy Abdelhameed ibrahim said h.Abd elkhalik shady Y.el-Mashad Abdelaziz A.Abdelhamid Department of Computer sciences College of Computer and Information SciencesPrincess Nourah Bint Abdulrahman UniversityRiyadh11671Saudi Arabia Department of Communications and electronics Delta Higher Institute of Engineering and TechnologyMansoura35111Egypt Faculty of Artificial Intelligence Delta University for Science and TechnologyMansoura35712Egypt Computer Engineering and Control systems Department Faculty of EngineeringMansoura UniversityMansoura35516Egypt Department of Computer systems Engineering Faculty of Engineering at ShoubraBenha UniversityEgypt Department of Computer science Faculty of Computer and Information SciencesAin Shams UniversityCairo11566Egypt Department of Computer science College of Computing and Information TechnologyShaqra University11961Saudi Arabia

The design of an antenna requires a careful selection of its parameters to retain the desired ***,this task is time-consuming when the traditional approaches are employed,which represents a significant *** the other hand,machine learning presents an effective solution to this challenge through a set of regression models that can robustly assist antenna designers to find out the best set of design parameters to achieve the intended *** this paper,we propose a novel approach for accurately predicting the bandwidth of metamaterial *** proposed approach is based on employing the recently emerged guided whale optimization algorithm using adaptive particle swarm optimization to optimize the parameters of the long-short-term memory(LsTM)deep *** optimized network is used to retrieve the metamaterial bandwidth given a set of *** addition,the superiority of the proposed approach is examined in terms of a comparison with the traditional multilayer perceptron(ML),Knearest neighbors(K-NN),and the basic LsTM in terms of several evaluation criteria such as root mean square error(RMsE),mean absolute error(MAE),and mean bias error(MBE).Experimental results show that the proposed approach could achieve RMsE of(0.003018),MAE of(0.001871),and MBE of(0.000205).These values are better than those of the other competing models.

关键词： Metamaterial antenna long short term memory(LsTM) guided whale optimization algorithm(Guided WOA) adaptive dynamic particle swarm algorithm(AD-PsO)

sequence stratigraphic evaluation for the Abu Madi Formation,Abu Madi/el Qar'a/Khilala gas fields,onshore Nile Delta,Egypt

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Petroleum Research 2023年第4期8卷 514-523页

作者： Farouk I.Metwalli Amir Ismail M.s.Metwally ibrahim M.el shafei Geology Department Faculty of ScienceHelwan UniversityCairoEgypt Desert Research Center CairoEgypt Petrobel Oil Company CairoEgypt

The present study aims to integrate a large set of geological and geophysical data into a comprehensive model describing the depositional features of the Abu Madi/el Qar'a/Khilala gas *** model is based on the sequence stratigraphic framework of the Abu Madi Formation defined using cores,well logs,and time-migrated seismic *** trace attribute sections and relative acoustic impedance sections are also used.A possible depositional pattern for the main Level Ill is established,based on the lithological and petrophysical information derived from the seismic data *** Abu Madi For-mation can be regarded as a depositional sequence recording the progressive drowning of the incised *** sequence is bounded at the base by an erosional unconformity,created by a drop in the level of the Late Messinian sea,and at the top by a drowning unconformity related to the Early Pliocene *** bottom of Level II divides the Abu Madi sequence into two smaller *** both sequences,gas-bearing traps can be found in the Lowstand systems Tracts,represented by the fluvial Level Ill and fluvial-deltaic Level Il,respectively.

关键词： Abu Madi gas field el Qar'a area Khilala area sequence stratigraphy analysis Onshore Nile Delta Abu Madi Formation

Theoretical prediction of structural,electronic and optical properties of quaternary alloy Zn_(1-x)Be_xs_yse_(1-y)

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Chinese Physics B 2012年第3期21卷 321-327页

作者： hacini K Meradji h Ghemid s el haj hassan F Laboratoire LPR D'epartement de PhysiqueFaculté des SciencesUniversité de Annaba Laboratoire de physique des Matériaux Faculté des SciencesUniversité Libanaise

Within density functional theory based on the full potentiM-linearized augmented plane wave method, we carry out the first-principles calculation of the structural, electronic, and optical properties of the zinc blende quaternary alloy Zn1-xBexsyse1-y. The Perdew-Burke-Ernzerhof generaized gradient approximation based on the optimization of total energy and the Engel-Vosko generalized gradient approximation based on the optimization of the corresponding potential are used. Our investigation on the effect of the composition on lattice constants, bulk modulus, band gap, optical dielectric constant, and refractive index shows a non-linear dependence. The energy gap Eg（x, y） has been determined over the entire compositions x and y. In addition, the energy band gap of the technologically important quaternary alloy Znl-xBexsyse1-y in conditions of being lattice matched to Zns substrate has been investigated. It is noteworthy that the present work is the first theoretical study of the quaternary alloy of interest.

关键词： density functional theory full potential-linearized augmented plane wave method qua-ternary alloy lattice-matched substrate

A new approach for modelling the damped helmholtz oscillator:applications to plasma physics and electronic circuits

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Communications in Theoretical Physics 2021年第3期73卷 119-130页

作者： s A el-Tantawy Alvaro h salas M R Alharthi Department of Physics Faculty of SciencePort Said UniversityPort Said 42521Egypt Research Center for Physics(RCP) Department of PhysicsFaculty of Science and ArtsAl-MikhwahAl-Baha UniversitySaudi Arabia Department of Mathematics Universidad National de ColombiaUniversidad National de Colombia-Nubia Campus Derpartment of Mathematics and Statistics FIZMAKO Research GroupColombia Department of Mathematics and statistics College of ScienceTaif UniversityPO Box 11099Taif 21944Saudi Arabia

In this paper,a new approach is devoted to find novel analytical and approximate solutions to the damped quadratic nonlinear helmholtz equation(hE)in terms of the Weiersrtrass elliptic *** exact solution for undamped hE(integrable case)and approximate/semi-analytical solution to the damped hE(non-integrable case)are given for any arbitrary initial *** a special case,the necessary and sufficient condition for the integrability of the damped hE using an elementary approach is *** general,a new ansatz is suggested to find a semi-analytical solution to the non-integrable case in the form of Weierstrass elliptic *** addition,the relation between the Weierstrass and Jacobian elliptic functions solutions to the integrable case will be derived in ***,we will make a comparison between the semi-analytical solution and the approximate numerical solutions via using Runge-Kutta fourth-order method,finite difference method,and homotopy perturbation method for the first-two ***,the maximum distance errors between the approximate/semi-analytical solution and the approximate numerical solutions will be *** real applications,the obtained solutions will be devoted to describe the characteristics behavior of the oscillations in RLC series circuits and in various plasma models such as electronegative complex plasma model.

关键词： damped and undamped helmholtz equation Korteweg-de Vries type equation plasma oscillations nonlinear RLC circuits Weierstrass ellliptic function periodical solution

Effect of Conductive Fillers on the Cyclic stress-strain and Nano-scale Free Volume Properties of silicone Rubber

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Chinese Journal of Polymer science 2014年第5期32卷 558-567页

作者： M.h.Abd-el salam s.el-Gamal M.Mohsen D.M.Abd el-Maqsoud Physics Department Faculty of Education Ain Shams University Physics Department Faculty of Science Ain Shams University

The effect of carbon black （CB） and graphite （G） powders on the macroscopic and nano-scale free volume properties of silicone rubber based on poly（di-methylsiloxane）（PDMs） was studied through thermal and cyclic mechanical measurements, as well as with positron annihilation lifetime spectroscopy （PALs）. The melting temperature of the composites （Tm） and the endothermic enthalpy of melting （Δhm） were estimated by differential scanning calorimetry （DsC）. Tm and the degree of crystallinity （χc） of PDMs composites were found to decrease with increasing the CB content. This can be explained due to the increase in physical cross-linking which results in a decrease in the crystallite thickness. Besides, χc was found to be dependent on the filler type. Cyclic stress-strain behavior of PDMs loaded with different contents of filler has been studied. Mullins ratio （RM） was found to be dependent on the filler type and content. It was found that, RM increases with increasing the filler content due to the increase in physical cross-linking which results in a decrease in the size of free volume, as observed through a decrease of the o-Ps lifetime τ3 measured by PALs. Moreover, the hysteresis in PDMs-CB composites was more pronounced than in PDMs-G composites. Furthermore, a correlation was established between the free volume Vf and the mechanical properties of PDMs composites containing different fillers. A negative correlation was observed between Vf and RM.

关键词： Positron annihilation Positronium Free volume si-rubber Composite Cyclic mechanical properties.

Cylindrical Three-Dimensional Dust-Ion Acoustic Propagation in Plasmas

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Communications in Theoretical Physics 2018年第9期69卷 325-330页

作者： s.K.el-Labany E.K.el-shewy h.N.Abd el-Razek A.A.el-Rahman Theoretical Physics Group Faculty of Science Domietta University Department of Physics Taibah University Theoretical Physics Group Faculty of Science Mansoura University Department of Physics Faculty of Science Assiut University

Wave properties of solitons in an unmagnetized four-component dusty plasma system contains isothermal distributed electrons, mobile ions, and negative-positive dusty grains have been examined. To study DIA wave properties,a reductive perturbation (RP) analysis is used. By a reductive perturbation (RP) analysis under convenient coordinate transformation, the three dimension Kadomtsev-Petviashvili equation in cylindrical coordinates is obtained. The effects of dust grain charge on soliton pulse structures are studied. More specifically, solitary profile depending on the axial,radial, and polar angle coordinates with time is discussed. This investigation may be viable in plasmas of the Earth’s mesosphere.

关键词： dust plasmas 3D-CKP equation dusty-ion acoustic solitary waves isothermal electrons