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Crystallization kinetics of overlapping phases in Se70Te15Sb15 using isoconversional methods

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Progress in Natural Science:materials International 2015年第2期25卷 169-177页

作者： m.A.abdel-Rahim m.m.Hafiz A.Z.mahmoud Physics Department Faculty of ScienceAssiut University Assiut 71516 Egypt

The crystallization kinetics of Se70Te15Sb15 chalcogenide glass was studied by Differential Scanning Calorimetry(DSC) under non-isothermal conditions. This glass was found to have a double glass transition and double overlapped crystalline phases. The overlapped crystalline phases were successfully separated using the Gaussian fit model. The activation energy, Ec, and Avrami index, n, were determined by analyzing the data using the matausita et. al. method. A strong heating rate depending on the activation energy for the two crystalline peaks was observed. The results indicated that the transformation from amorphous to crystalline phases is a complex process involving different mechanisms of nucleation and growth. The variation of activation energy with crystalline fraction was determined by Kissenger–Akahira–Sunose(KAS) method. The obtained results of directly fitting the experimental DSC data to the calculated DSC curves indicated that the crystallization process of Se70Te15Sb15 glass cannot be satisfactorily described by the Johnson–mehl–Avrami(JmA) model. Simulation results indicated that the Sestak–Berggren(SB) model is more suitable to describe the crystallization process for the studied glass. The crystalline phases for the two events were identified by using x-ray diffraction(XRD) and scanning electron microscopy(SEm).

关键词： Chalcogenides glasses Differential Scanning Calorimetry(DSC) Electron microscopy X-ray diffraction

New Aspects of Field Entropy Squeezing as an Indicator for mixed State Entanglement in an Effective Two-Level System with Stark Shift

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Chinese Physics Letters 2011年第12期28卷 24-27页

作者： S.abdel-Khalek m.m.A.Ahmed A-S F.Obada Department of mathematics Faculty of ScienceSohag University82524 SohagEgypt Department of mathematics Faculty of ScienceTaif University21974 TaifSaudi Arabia Department of mathematics Faculty of ScienceAl-Azhar UniversityNasr City11884 CairoEgypt

We present an effective two-level system in interaction through two-photon processes with a single mode quantized electromagnetic field,initially prepared in a coherent *** entropy squeezing as an indicator of the entanglement in a mixed state system is *** temporal evolution of the negativity,Wehrl entropy,Wehrl phase distribution and field entropy squeezing are *** results highlight the important roles played by both the Stark shift parameters and the mixed state setting in the dynamics of the Wehrl entropy,Wehrl phase distribution and field entropy squeezing.

关键词： state entropy system

Cavity control as a new quantum algorithms implementation treatment

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Frontiers of physics 2018年第1期13卷 187-199页

作者： m. AbuGhanem A. H. Homid m. abdel-Aty University of Science and Technology Zewail City of Science and Technology Giza 12588 Egypt Departme-nt of mathematics Faculty of Science Ain-Shams University Cairo 11566 Egypt Faculty of Science Al-Azhar University Assiut 71524 Egypt

Based on recent experiments [Nature 449, 438 （2007） and Nature Physics 6, 777 （2010）], a new approach for realizing quantum gates for the design of quantum algorithms was developed. Accordingly, the operation times of such gates while functioning in algorithm applications depend on the number of photons present in their resonant cavities. multi-qubit algorithms can be realized in systems in which the photon number is increased slightly over the qubit number. In addition, the time required for operation is considerably less than the dephasing and relaxation times of the systems. The contextual use of the photon number as a main control in the realization of any algorithm was demonstrated. The results indicate the possibility of a full integration into the realization of multi-qubit multiphoton states and its application in algorithm designs. Yhrthermore, this approach will lead to a successful implementation of these designs in future experiments.

关键词： quantum computation quantum algorithms implementation cavity control

Linearly and Quadratically Separable Classifiers Using adaptive Approach

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Journal of Computer Science & Technology 2011年第5期26卷 908-918页

作者： mohamed abdel-Kawy mohamed Ali Soliman Rasha m.Abo-Bakr Department of Computer and Systems Engineering Faculty of EngineeringZagazig UniversityZagazigEgypt Departement of mathematics Faculty of ScienceZagazig UniversityZagazigEgypt

This paper presents a fast adaptive iterative algorithm to solve linearly separable classification problems in R *** each iteration,a subset of the sampling data （n-points,where n is the number of features） is adaptively chosen and a hyperplane is constructed such that it separates the chosen n-points at a margin and best classifies the remaining *** classification problem is formulated and the details of the algorithm are ***,the algorithm is extended to solving quadratically separable classification *** basic idea is based on mapping the physical space to another larger one where the problem becomes linearly *** illustrations show that few iteration steps are sufficient for convergence when classes are linearly *** nonlinearly separable data,given a specified maximum number of iteration steps,the algorithm returns the best hyperplane that minimizes the number of misclassified points occurring through these *** with other machine learning algorithms on practical and benchmark datasets are also presented,showing the performance of the proposed algorithm.

关键词： linear classification quadratic classification iterative approach adaptive technique

On Special Curves According to Darboux Frame in the Three Dimensional Lorentz Space

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Computers, materials & Continua 2018年第3期54卷 229-249页

作者： H.S.abdel-Aziz m.Khalifa Saad math.Dept. Faculty of ScienceSohag University82524 SohagEgypt. math.Dept. Faculty of ScienceIslamic University of Madinah170 El MadinahKSA

In the light of great importance of curves and their frames in many differentbranches of science, especially differential geometry as well as geometric properties andthe uses in various fields, we are interested here to study a special kind of curves calledSmarandache curves in Lorentz 3-space. Then, we present some characterizations for thesecurves and calculate their Darboux invariants. moreover, we classify TP, TU, PU andTPU-Smarandache curves of a spacelike curve according to the causal character of thevector, curve and surface used in the study. Besides, we give some of differential geometricproperties and important relations between that curves. Finally, to demonstrate ourtheoretical results a computational example is given with graph.

关键词： Smarandache curves spacelike curve timelike surface Darboux frame

On the Relationship between Climatic Variables and Pressure Systems over Saudi Arabia in the Winter Season

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advances in Atmospheric Sciences 2015年第5期32卷 690-703页

作者： H.m.HASANEAN H.abdel BASSET m.A.A.HUSSEIN Department of meteorology Faculty of Meteorology Environment and Arid Land AgricultureKing Abdulaziz University Department of meteorology and Astronomy Faculty of Science Al-Azhar University

The synoptic circulation over Saudi Arabia is complicated and frequently governed by the effect of large-scale pressure systems. In this work, we used NCEP–NCAR global data to illustrate the relationship between climatic variables and the main pressure systems that affect the weather and climate of Saudi Arabia, and also to investigate the influence of these pressure systems on surface air temperature（SAT） and rainfall over the region in the winter season. It was found that there are two primary patterns of pressure that influence the weather and climate of Saudi Arabia. The first occurs in cases of a strengthening Subtropical High（Sub H）, a weakening Siberian High（Sib H）, a deepening of the Icelandic Low（Ice L）, or a weakening of the Sudanese Low（Sud L）. During this pattern, the Sub H combines with the Sib H and an obvious increase of sea level pressure（SLP） occurs over southern European, the mediterranean, North Africa, and the middle East. This belt of high pressure prevents interaction between midlatitude and extratropical systems, which leads to a decrease in the SAT,relative humidity（RH） and rainfall over Saudi Arabia. The second pattern occurs in association with a weakening of the Sub H, a strengthening of the Sib H, a weakening of the Ice L, or a deepening of the Sud L. The pattern arising in this case leads to an interaction between two different air masses： the first（cold moist） air mass is associated with the mediterranean depression travelling from west to east, while the second（warm moist） air mass is associated with the northward oscillation of the Sud L and its inverted V-shape trough. The interaction between these two air masses increases the SAT, RH and the probability of rainfall over Saudi Arabia, especially over the northwest and northeast regions.

关键词： climatic variables pressure system surface air temperature rainfall relative humidity Saudi Arabia

On the nonclassical dynamics of cavity-assisted four-channel nonlinear coupler

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Chinese Physics B 2018年第11期27卷 498-505页

作者： Rafael Julius abdel-Baset m A Ibrahim Pankaj Kumar Choudhury Hichem Eleuch Faculty of Applied Sciences Universiti Teknologi MARA (UiTM) Faculty of Applied Sciences Universiti Teknologi Mara (UiTM) Perak Tapah Campus Institute of microengineering and Nanoelectronics Universiti Kebangsaan Malaysia Department of Applied Sciences and mathematics College of Arts and Sciences Abu Dhabi University Institute for Quantum Science and Engineering Texas A&M University College Station

The non-classical properties of light propagating in four-channel Kerr waveguides, confined in an optical cavity, are studied. The solution to the hamiltonian of field operators is obtained semi-analytically by using symmetrically ordered phase-space representation. Full quantum analysis of the input coherent fields displays a strong transition of photon property between the super-Poissonian and sub-Poissonian statistics. It is found that the cavity-assisted multichannel system exhibits enhanced squeezing both in single-and compound-mode. This multichannel system may be utilized as an efficient quantumlight generator.

关键词： squeezed states Kerr effects Langevin equation

Ensuring the possibility of using thorium as a fuel in a pressurized water reactor(PWR)

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Nuclear Science and Techniques 2021年第12期32卷 37-52页

作者： mohamed Y.m.mohsen mohamed A.E.abdel-Rahman Aabdelghafar Galahom Nuclear Engineering Department Military Technical CollegeKobry ElkobbahCairoEgypt Higher Technological Institute 10th of Ramadan CityEgypt

The possibility of utilizing thorium as a fuel in a pressurized water reactor(PWR)has been proven from the neutronic perspective in our previously published work without assessing the thermal hydraulic(TH)and solid structure ***,the TH and solid structure performances must be studied to confirm these results and ensure the possibility of using a thorium-based fuel as an excellent accident-tolerant *** TH and solid structure performances of thorium-based fuels were investigated and compared with those of UO_(2).The radial and axial power peaking factors(PPFs)for UO_(2),(^(232)Th,^(235)U)O_(2),and(^(232)Th,^(233)U)O_(2)were examined with a PWR assembly to determine the total PPF of each *** Gd_(2)O_(3)and Er_(2)O_(3)were tested as burnable absorbers(BAs)to manage the excess reactivity at the beginning of the fuel cycle(BOC)and reduce the total ***_(2)O_(3)resulted in a more significant reduction to the total PPF and,therefore,a greater reduction to the temperature distribution compared to Gd_(2)O_(3).Given these results,we analyzed the effects of adding Er_(2)O_(3)to thorium-based fuels on their TH and solid structure performances.

关键词： Thermal hydraulic(TH) Solid structure Thorium-based fuel Gd2O3 Er_(2)O_(3)

Electrochemical Detection of the Different Species of Levofloxacin Using PVC,Carbon Paste and Screen‑Printed Electrodes:Effect of pH

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Journal of Analysis and Testing 2018年第2期2卷 175-183页

作者： Nour ElDin T.abdel Ghani Fatehy m.abdel‑Haleem Sonia mahmoud Rasha m.El Nashar Chemistry Department Faculty of ScienceCairo UniversityGizaEgypt

The zwitterionic compound,levofloxacin,was determined for the first time at different pH values in pure samples,pharmaceutical preparations and spiked serum and urine *** types of potentiometric sensors including poly(vinyl chloride)membrane electrode,carbon paste electrode and screen printed electrode,containing the ion pair levofloxaciniumphosphomolybdate as the electroactaive species,were used for this *** effect of pH is the key factor in determining the ratio of the different species that can exist in the medium(zwitterionic,monocationic,dicationic,anionic and neutral),and so it is the controller of the electrochemical *** different sensors were fully characterized and optimized in terms of composition,pH effect,selectivity,response and *** different sensors showed reliable reversibility and could be utilized for the determination of the drug in real spiked physiological fluids with reliable recovery values.

关键词： Levofloxacin Zwitterionic Poly(vinyl-chloride)(PVC)membrane electrode Carbon paste electrode(CPE) Screen-printed electrode(SPE)