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The Control of Stochastic Complex Damped Nonlinear Systems

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The Control of Stochastic Complex Damped Nonlinear Systems

Stabilization of a Nonlinear Stochastic Complex Damped System using Random Force

第十一届全国非线性振动学术会议暨第八届全国非线性动力学和运动稳定性学术会议

作者： gamal m.mahmoud Departm ent of mathematics Faculty of ScienceUniversity of Assiut

Complex damped nonlinear systems have been introduced and studied in our previous *** systems appear in many important applications in engineering, physics and mechanics,for example,in rotor dynamics,robots,shells and in high energy *** the aim of this paper is to continue our investigations by studying these systems with random *** effect of random phase for these systems is *** interested system demonstrates unstable periodic attractors when the intensity of random noise equals zero,and we show that the unstable dynamical behavior will be stabilized as the intensity of random noise properly *** phase plot and the time evolution are carried out to confirm the obtained results of Poincar(?) map analysis and top Lyapunov exponent on dynamical behavior of *** agreement is found between these results.

关键词： complex damped dynamical system top Lyapunov exponent Poincar(?) map analysis random phase stabilization time evolution

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Stabilization of a Nonlinear Stochastic Complex Damped Syste...

Double compound combination synchronization among eight n-dimensional chaotic systems

中国数学力学物理学高新技术交叉研究学会第十二届学术年会

作者： gamal m.mahmoud Department of mathematics Faculty of ScienceUniversity of AssiutAssiut71516

＜正＞The aim of this chapter is to observe effects of the random force for a nonlinear stochastic complex damped *** noise intensity of random phase is adjusted and applied to stabilize the interested system from unstable behavior by the criterion of the change of sign for the top Lyapunov ***,the Poincaré map analysis is carried out and excellent agreement between these results is found.

关键词： complex damped dynamical system top Lyapunov exponent Poincarémap analysis random phase

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Chinese Physics B 2018年第8期27卷 150-158页

作者： gamal m.mahmoud Tarek m Abed-Elhameed Ahmed A Farghaly Department of mathematics Faculty of Science Assiut University

Depending on double compound synchronization and compound combination synchronization, a new kind of syn- chronization is introduced which is the double compound combination synchronization （DCCS） of eight n-dimensional chaotic systems. This kind may be considered as a generalization of many types of synchronization. In the communica- tion, based on many of drive and response systems, the transmitted and received signals will be more secure. Using the Lyapunov stability theory and nonlinear feedback control, analytical formulas of control functions are obtained to insure our results. The corresponding analytical expression and numerical treatment are used to show the validity and feasibility of our proposed synchronization scheme. The eight memristor-based Chua oscillators are considered as an example. Other examples can be similarly investigated. The proposed synchronization technique is supported using the mATLAB simula- tion outcomes. We obtain the same results of numerical treatment of our synchronization using simulation observations of our example.

关键词： double compound synchronization compound combination synchronization chaotic system Lya-punov stability

Potential detoxification of aflatoxin B2 using Kluyveromyces lactis and Saccharomyces cerevisiae integrated nanofibers

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BIOCELL 2017年第2期41卷 67-73页

作者： mahmoud mOUSTAFA TAREK TAHA mOHAmED ELNOUBY NEHAL EL-DEEB gamal HAmAD m.A.ABUSAIED SULAImAN ALRUmmAN Department of Biology College of ScienceKing Khalid University9004AbhaKingdom of Saudi Arabia(KSA) Botany Department Faculty of ScienceSouth Valley UniversityQenaEgypt Environmental Biotechnology Department Genetic Engineering and Biotechnology Research Institute(GEBRI)City of Scientific Research and Technological Applications(SRTA-City)New Borg El-Arab City21934AlexandriaEgypt Composite and Nanostructured materials Research Department Advanced Technology and New Materials Research InstituteCity of Scientific Research and Technological Applications(SRTA-City)New Borg El-Arab City21934AlexandriaEgypt Department of Biopharmaceutical Product Research Genetic Engineering and Biotechnology Research Institute(GEBRI)City of Scientific Research and Technological Applications(SRTA-City)New Borg El-Arab City21934AlexandriaEgypt Food Technology Department Arid Land Cultivation Research Institute(ALCRI)City of Scientific Research and Technological Applications(SRTA-City)New Borg El-Arab City21934AlexandriaEgypt Polymer materials Research Department Advanced Technology and New Materials Research InstituteCity of Scientific Research and Technological Applications(SRTA-City)New Borg El-Arab City21934AlexandriaEgypt

Current investigation has shown that human exposure to aflatoxins is not limited to the administration of contaminated cereals,but water is another possible *** study was aimed to design easily applicable method to eliminate aflatoxin B2(AFB2)from contaminated drinking *** has been used for preparation of probiotic-coated polyvinyl alcohol(PVA)and cellulose acetate(CA)*** of these hybrid nanofibers were studied by scanning electron microscopy(SEm)and Fourier-transformed infrared spectroscopy(FT-IR).SEm showed the proper coating of probiotic strains(Kluyveromyces lactis CBS 2359 and Saccharomyces cerevisiae ATCC 9763)on both nanofiber *** areas(1-5 cm^(2))of the probiotic-nanofiber hybrid were used to enhance the removal of 20 ng/ml of aflatoxin B2(AFB2)from prepared AFB2-contaminated water over *** revealed that a 5 cm^(2) area of probiotic-coated PVA nanofibers can eliminate 97.5% of AFB2 as compared to 87.5%,90.5%,93.5%,and 95.5%,for 1 cm2,2 cm^(2),3 cm^(2),and 4 cm^(2),respectively,while probiotic-coated CA nanofibers were slightly less ***,the cytotoxicity of probiotics-CA treated water on cultured human fibroblasts was almost 10 times lower than the cytotoxicity recorded in probiotics-PVA treated ***,results of the current research suggest that probiotics-polymer nanofiber membranes can be used as an extra stage in the water purification system for the treatment of AFB2-contaminated water.

关键词： Nanofibers Aflatoxin B2 Cytotoxicity Water treatment

Electronic Properties of Red P-Type Tl2S5 Single Crystals

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Chinese Physics Letters 2005年第6期22卷 1530-1532页

作者： G.A.gamal m.AbouZied A.A.Ebnalwaled DepartmentofPhysics FacultyofScienceSouthValleyUniversityQena83511Egypt

Single crystals of red Tl2S5 were prepared by a special modified verticalBridgman and Stockbarger technique. This growth was performed in our laboratory. The influences oftemperature on the electrical conductivity, Hall mobility, carrier concentration, and thermoelectricpower (TEP) were carried out in the temperature range 277-413 K. Throughout these measurements,various physical parameters such as effective mass of charge carriers, carrier mobility, diffusioncoefficient, and the relaxation time for both majority and minority carriers were found.

关键词： THALLIUm

Exploitation of the antibacterial,antibiofilm and antioxidant activities of Salvadora Persica(miswak)extract

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Journal of Bioresources and Bioproducts 2023年第1期8卷 59-65页

作者： gamal m.El-Sherbiny Ahmed mohamed Gazelly mohammed H.Sharaf Saad A.moghannemm Shehata m.E mahmoud K.A.Ismail Ahmad S.El-Hawary Botany and microbiology Department Faculty of Science(Boys)Al-Azhar UniversityCairo 11884Egypt

The Salvadora persica(***)*** stick,usually known as miswak,is still being em-ployed as an oral hygiene agent for plaque and gingivitis *** study aims to assess the antibacterial,antibiofilm,antioxidant,and phytochemical profile of *** *** ***-sica was purchased from a local market,grinded and extracted with petroleum *** disk dif-fusion,microdilution,and micro-plate assays were performed to evaluate the antibacterial and an-tibiofilm activities of the prepared extract at different concentrations against𝛽-lactam resistance Streptococcus *** radical scavenging 2,2-diphenyl-1-picrylhydrazyl(DPPH)and stable radical cationic chromophore,2,2-azinobis-(3-ethylbenzothiazoline-6-sulfonate)(ABTS)methods were used to determine their antioxidant *** and spectrometric analyses were performed using gas chromatography-mass(GC-mS)*** minimum inhibitory concentration(mIC)of *** extract against𝛽-lactam resistance Streptococcus species ranged from 6.25 to 12.5 mg/*** maximum suppression of biofilm formation by *** extract was observed at mIC with a percentage of 68.66%,against Streptococcus *** *** ex-tract exhibited antioxidant activity with IC 50 of 20μg/mL and 35μg/mL from DPPH and ABTS,*** phytochemical characterization showed the presence of 22 compounds with ma-jor compounds;benzyl isothiocyanate(36.21%)and n-hexadecanoic acid(27.62%).The *** extract exhibited antibacterial activity against𝛽-lactam resistant Streptococcus species,showing a promising natural alternative that could be a treatment option.

关键词： β-lactam resistance Streptococcus species S.persica extract Antibacterial Antibiofilm Antioxidant GC-mS analysis

Spherically symmetric solution in higher-dimensional teleparallel equivalent of general relativity

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Chinese Physics B 2013年第2期22卷 120-127页

作者： gamal G.L.Nashed Center for Theoretical Physics British University in EgyptSherouk City 11837P.O.Box 43Egypt mathematics Department Faculty of ScienceAin Shams UniversityCairo11566Egypt

A theory of（N＋1）-dimensional gravity is developed on the basis of the teleparallel equivalent of general relativity（TEGR）.The fundamental gravitational field variables are the（N＋1）-dimensional vector fields,defined globally on a manifold m,and the gravitational field is attributed to the *** form of Lagrangian density is quadratic in torsion *** then give an exact five-dimensional spherically symmetric solution（Schwarzschild（4＋1）-dimensions）.Finally,we calculate energy and spatial momentum using gravitational energy-momentum tensor and superpotential 2-form.

关键词： (N+1)-dimensional teleparallel equivalent of general relativity five-dimensional solution energy and momentum

Investigation of a New Formula for Gurney Velocity Estimation

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火炸药学报 2018年第4期41卷 340-344页

作者： Tamer Elshenawy Ahmed Elbeih Qing ming Li gamal m. Abdo Technical Research Centre Cairo Egypt military Technical College Kobry Elkobbah Cairo Egypt The University of manchester School of Mechanical Aerospace and Civil Engineering Manchester UK mechanical Engineering Department Modern Acade

The formula for the analytical calculations of the shaped charge jetting parameters exhibit an explicit dependence upon the Gurney velocity of an explosive *** attempts have been done to approximate the characteristic constant 2E^(1/2) and to make its use more *** is shown herein that the characteristic Gurney velocity parameter depends on the ratio of the Chapman Jouguet-pressure to explosive impulse ratio by the formula:2E^(1/2)=0.2415(P_(CJ)/I_(SP)ρ_0)-970.76,where PCJis the Chapman Jouguet pressure(Pa),ISPis the specific impulse of the explosive used as a monopropellant(N·s/kg)andρois the explosive density(kg/m^3).The proposed empirical formula was found to be reasonable and quite accurate approximation that can be implemented over a wide range of explosives,where the maximum deviation between the measured and the calculated Gurney velocities was nearly 6%.Besides,the proposed approach has been used analytically to calculate the jet tip velocity of a small caliber shaped charge,which is measured *** difference between the measured and the calculated jet tip velocity was only 1.6%.

关键词：火药理论研究化学分析

Energy and momentum of general spherically symmetric frames on the regularizing teleparallelism

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Chinese Physics B 2012年第1期21卷 101-109页

作者： gamal G.L.Nashed Centre for Theoretical Physics The British University in EgyptEl-Sherouk City 11837Egypt mathematics Department Faculty of ScienceAin Shams University

In the context of the covariant teleparallel framework, we use the 2-form translational momentum to compute the total energy of two general spherically symmetric frames. The first one is characterized by an arbitrary function H（r）, which preserves the spherical symmetry and reproduces all the previous solutions, while the other one is characterized by a parameter ξ which ensures the vanishing of the axial of trace of the torsion. We calculate the total energy by using two procedures, i.e., when the WeitzenbSck connection Гα^β is trivial, and show how H（r） and ξ play the role of an inertia that leads the total energy to be unphysical. Therefore, we take into account Гα^β and show that although the spacetimes we use contain an arbitrary function and one parameter, they have no effect on the form of the total energy and momentum as it should be.

关键词： gravitation teleparallel gravity energy-momentum conserved currents