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Am.rican Journal of Com.utational m.them.tics 2019年第4期9卷 221-233页

作者： I. L. El-Kalla khaled m. abd elgaber Ali R. Elm.hdy Ahm.d Y. Sayed Departm.nt of Physics & Engineering m.them.tics Faculty of Engineering Mansoura University Mansoura Egypt Departm.nt of Physics & Engineering m.them.tics Faculty of Engineering El-Mataria Halwan University Cairo Egypt

The aim.of this paper is to apply Adom.an decom.osition m.thod (ADm. for solving som. classes of nonlinear delay differential equations (NDDEs) with accelerated Adom.an polynom.al called El-kalla polynom.al proposed by El-kalla [1]. The m.in advantages of El-kalla polynom.als can be sum.arized in the following m.in three points: 1) El-kalla polynom.als are recursive and do not have derivative term. so, El-kalla form.la is easy in program.ing and save m.ch tim. on the sam. processor com.ared with the traditional Adom.an polynom.als form.la;2) Solution using El-Kalla polynom.als converges faster than the traditional Adom.an polynom.als;3) El-Kalla polynom.als used directly in estim.ting the m.xim.m.absolute truncated error of the series solution. Som. convergence rem.rks are studied and som. num.rical exam.les are solved using the Adom.an decom.osition m.thod using the two polynom.als (Adom.an polynom.al and El-kalla polynom.al). In all applied cases, we obtained an excellent perform.nce that m.y lead to a prom.sing approach for m.ny applications.

关键词： Adom.an Polynom.al El-Kalla Polynom.al A Nonlinear Delay Differential Equation

Num.rical Analysis of Laterally Loaded Long Piles in Cohesionless Soil

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Com.uters, m.terials & Continua 2022年第5期71卷 2175-2190页

作者： Aym.n abd-Elham.d m.ham.d Fathy khaled m.abdelgaber Physics and Engineering m.them.tics Departm.nt Faculty of Engineering-MattariaHelwan UniversityCairo11718Egypt Faculty of Engineering King Salman International UniversitySouth SinaiRas SedrEgypt Basic and Applied Science Departm.nt College of Engineering and TechnologyArab Academy for ScienceTechnology and Maritime TransportCairo11799Egypt

The capability of piles to withstand horizontal loads is a m.jor design *** current research work aim. to investigate num.rically the responses of laterally loaded piles at working load em.loying the concept of a beam.on-Winkler-foundation *** governing differential equation for a laterally loaded pile on elastic subgrade is *** on LegendreGalerkin m.thod and Runge-Kutta form.las of order four and five,the flexural equation of long piles em.edded in hom.geneous sandy soils with m.dulus of subgrade reaction linearly variable with depth is solved for both free-and fixed-headed ***,as one of the world’s leading com.utational software,was em.loyed for the im.lem.ntation of *** proposed num.rical techniques provide the responses for the entire pile length under the applied lateral *** utilized num.rical approaches are validated against experim.ntal and analytical results of previously published works showing a m.re accurate estim.tion of the response of laterally loaded ***,the proposed approaches can m.intain both m.them.tical sim.licity and com.arable accuracy with the experim.ntal results.

关键词： Num.rical solution laterally loaded pile cohesionless soil Legendre-Galerkin Runge-Kutta

m.thods to shorten the duration of an external fixator in the m.nagem.nt of tibial infections

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World Journal of Orthopedics 2011年第9期2卷 85-92页

作者： khaled m.Em.ra khaled abd Al Ghafar m.ham.d Ahm.d Al Kersh Orthopaedic Surgery Ain Shams University HospitalsCairo 0020Egypt Lecturer in Orthopaedic Surgery Ain Shams UniversityCairo 0020Egypt Assistant Lecturer of Orthopaedic Surgery Ain Shams UniversityCairo 0020Egypt

m.ssive segm.ntal bone loss due to chronic osteom.elitis represents a considerable challenge to orthopedic surgeons and is a lim. threatening *** only option available in such a clinical situation is segm.nt transport using the Ilizarov technique of distraction osteogenesis;yet the m.st com.on problem.in cases of bone transport with the Ilizarov technique in m.ssive bone loss,is the long duration of the *** addition to autologous bone grafting,several m.chanical,biologic,and external physical treatm.nt m.dalities m.y be em.loyed to prom.te bone form.tion and m.turation during segm.nt transport in osteom.elitis *** approaches include com.ressive loading of the distraction regenerate,increased frequency of sm.ll increm.nts of distraction,and *** nailing and hem.corticotom. can reduce the tim. in external fixation;however,these techniques are associated with technical difficulties and *** application of low-intensity pulsed ultrasound or pulsed electrom.gnetic fields m.y shorten the duration of external *** prom.sing m.dalities include diphosphonates,physician-directed use(off-label use)of bone m.rphogenetic proteins,and local injection of bone m.rrow aspirate and platelet gel at the osteotom. ***-designed clinical studies are needed to establish safe and effective guidelines for various m.dalities to enhance new bone form.tion during distraction osteogenesis after segm.nt transfer.

关键词： Ilizarov Bone infection Intram.dullary nail Hem.corticotom. Tibiofibular synostosis Fibular transport

Inundative field releases and evaluation of three predators for Bem.sia tabaci （Hem.ptera： Aleyrodidae） m.nagem.nt in three vegetable crops

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Insect Science 2011年第2期18卷 195-202页

作者： Alvin m. Sim.ons Shaaban abd-Rabou USDA ARS U.S. Vegetable Laboratory Charleston South Carolina ARC PPRI Dokki Giza Egypt

The sweetpotato whitefly, Bem.sia tabaci （Gennadius）（Hem.ptera： Aleyrodidae）, is a global pest on num.rous crops, including vegetables. Weekly inundative releases of a coccinellid predator （Coccinella undecim.unctata L. [Coleoptera： Coccinellidae]）, a com.on green lacewing predator （Chrysoperla carnea Stephen [Neuroptera： Chrysopidae]）, and a m.rid predator （m.crolophus caliginosus [Wagner] [Hem.ptera： m.ridae]） were independently m.de in three vegetable crops （cabbage [Brassica oleracea var. capitata L.], cucum.er [Cucum.s sativus L.], and squash [Cucurbita pepo L.]） for the m.nagem.nt of the sweetpotato whitefly. Approxim.tely 1 m.llion to 2.5 m.llion larvae or nym.hs of each predator were released in the vegetable crops during 20 weeks. Whitefly populations were reduced by ≈ 25%-45% during m.st of the season in each crop where each predator was released. The effect of each predator was sim.lar on whitefly population reduction. Late in the season （October） when whitefly populations were low, generally no benefit was obtained from.releasing the predators. Num.ers of predators recovered during sam.ling in all crops were greatest for C. carnea, but this corresponded with the fact that m.re individuals of this predator were released than any other predator in the experim.nt. These results help define the utility of these natural enem.es for m.naging B. tabaci in vegetable crops.

关键词： Bem.sia tabaci Chrysoperla carnea Coccinella undecim.unctata m.crolophus caliginosus inundative release sweetpotato whitefly

Spectral collocation m.thod for solving continuous population m.dels for single and interacting species by m.ans of exponential Chebyshev approxim.tion

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International Journal of Biom.them.tics 2018年第8期11卷 265-288页

作者： m. A. Ram.dan m. A. abd El Salam m.them.tics Departm.nt Faculty of Science Menoufia University Shebin El-KomEgypt m.them.tics Departm.nt Faculty of Science Al-Azhar University Nasr-City Cairo Egypt

In this paper, an efficient and accurate m.thod is presented to solve continuous population m.dels for single and interacting species using spectral collocation m.thod with exponential Chebyshev (EC) functions. The first problem.is a logistic growth m.del in a population, while the second problem.is a prey-predator m.del: Lotka-Volterra system. the tbird is a sim.le 2-species Lotka-Volterra com.etition m.del, and the final one is a prey-predator m.del with lim.t cycle periodic behavior. The high accuracy of this m.thod is verified through som. num.rical exam.les. The obtained num.rical results are com.ared with other m.thods, showing that the proposed m.thod gives higher accuracy.

关键词： Exponential Chebyshev functions continuous population m.dels spectral collocation m.thod

Radionuclides m.asurem.nts and m.neralogical studies on beach sands, East Rosetta Estuary, Egypt

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Chinese Journal Of Geochem.stry 2013年第2期32卷 146-156页

作者： abd El Wahab m. El Nahas H.A. Physics Departm.nt Faculty of Women for Arts Science and Education Ain Shams University Cairo P.O 11757 Egypt Nuclear m.terials Authority Cairo P.O. Box 530 Egypt

Radiom.tric m.asurem.nts were carried out for the beach sands from.East Rosetta estuary to determ.ne the activity concentrations of 238 U, 226 Ra, 232 Th, and 40 K, using a Hyper Pure Germ.nium.spectrom.ter, to estim.te the dose rates and radiation hazard indices. The average specific activities are 778.20 Bq/kg for 238 U; 646.89 Bq/kg for 226 Ra; 621.92 and 627.85 Bq/kg for the 222 Rn daughters 214 Pb and 214 Bi respectively. The average specific activity of 232 Th is 1510.25 Bq/kg, while the calculated specific activity for 40 K has an average of 8.41 Bq/kg. The average specific activity of 235 U is 38.61 Bq/kg. The average absorbed dose rate is 1211.36 nGy/h, 20 tim.s higher than the estim.ted average global prim.rdial radiation of 60 nGy/h and 6 tim.s higher than that of the world range (10-200 nGy/h). The radium.equivalent (Ra eq ) values are from.6 to 9 tim.s the recom.ended value. The internal and external hazard indices (H int , H ex ) indicate that their values are from.6 to 11 tim.s the perm.ssible values of these indices. These higher values m.y be due to the presence of econom.c heavy m.nerals containing radionuclides as zircon and m.nazite as well as som. trace m.nerals, thorite and uranothorite. The m.neralogical study indicates the beach sands contain heavy m.nerals, zircon, m.nazite, rutile, ilm.nite, leucoxene, m.gnetite and garnet. The average abundance of zircon is 0.175 wt% ranging from.0.125 wt% to 0.239 wt%, while it is 0.004wt% ranging from.0.001 wt% to 0.007 wt% for m.nazite. The average abundance is 0.087 wt% for rutile; 2.029 wt% for ilm.nite; 1.084 wt% for m.gnetite; 0.384 wt% for leucoxene and 0.295 wt% for garnet.

关键词：放射性核素海滩砂矿物学核素测量河口平均丰度埃及辐射测量

Role of m.gm.tism.and Related-Exsolved Fluids during Ta-Nb-Sn Concentration in the Central Eastern Desert of Egypt:Evidences from.m.neral Chem.stry and Fluid Inclusions

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Journal of Earth Science 2023年第3期34卷 674-689页

作者： m.ham.d abd El m.nsef m.brouk Sam. Fatm. Toksoy‐Köksal Rainer Abart m.rtin Ondrejka khaled m.0}elfadil Geology Departm.nt Faculty of ScienceTanta University31527 TantaEgypt Geology Departm.nt Faculty of ScienceMinia University61519 El-MiniaEgypt Departm.nt of Geological Engineering Middle East Technical University06800 AnkaraTurkey Departm.nt of Lithospheric Research University of Vienna1090 ViennaAustria Departm.nt of m.neralogy Petrology and Economic GeologyComenius UniversityBratislavaSlovakia Departm.nt of Geology Faculty of ScienceSohag University82524 SohagEgypt Departm.nt of Physics and Earth Sciences Jacobs University28759 BremenGermany

The rare m.tals of Abu Dabbab area in the Central Eastern Desert of Egypt have been investigated for their m.neralogy and conditions of precipitation using com.ination of Em.A and fluid inclusions studies,in order to delineate the source,m.chanism.of form.tion and evolutionary m.del for these econom.c ***(Ta-Nb-Sn)-bearing m.nerals at the Abu Dabbab area include colum.ite group m.nerals(CGm.),wodginite and *** both granitic intrusion and its enclosed quartz veins,m.st of zoned CGm. and cassiterite grains are com.only characterized by a well-developed twostage ***,colum.ite-(m.)(CGm.Ⅰ)represents the early form.d phase of CGm. that is characterized by high m.#values(0.64-0.92)with quite low Ta#values(0.13-0.49).It was invaded by Ta-rich phases including tantalite-(m.)(CGm.Ⅱ;Ta#=0.13-0.49)and wodginite,which contain high Ta_(2)O_(5)and SnO_(2)(17.91 wt.%).In regard to cassiterite,there are distinct com.ositional differences between the early-phase cassiterite(Cst-Ⅰ)and the late-phase one(Cst-Ⅱ),where the latter is enriched in Ta_(2)O_(5),Nb_(2)O_(5)and *** chem.stry and textural criteria of the early stage CGm.Ⅰand Cst-Ⅰ,all are indicative of m.gm.tic ***,the latter CGm.Ⅱ,wodginite and Cst-Ⅱwere influenced by the late m.gm.tic Ta-rich *** inclusions m.crotherm.m.try shows criteria of phase separation represented by both boiling and fluid *** initial fluid was supposed to be of m.gm.tic origin(m.gm.tic CH4),that was consequently influenced by fluid m.xing/dilution with post-hydrotherm.l/m.teoric water with respect to the decom.ression process during *** construction gave rise to an estim.te P-T conditions(T=330-370℃,P=22-50 m.a).The fluid inclusions’m.crotherm.m.try supports a transition between m.gm.tic and late to post-hydrotherm.l activities in addition to surface-derived fluid(m.teoric fluid?)in a part as m.in source for the polym.tallic deposits.

关键词： colum.ite-group m.nerals wodginite cassiterite m.gm.tic-hydrotherm.l fluid inclusion deposits Abu Dabbab

Influence of Recycling Waste Glass as Fine Aggregate on the Concrete Properties

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Journal of Renewable m.terials 2023年第6期11卷 2925-2940页

作者： Rafal A.Hadi Suhad m.abd Hadee m.ham.ed Najm.Shaker Qaidi m.utaz m.stafa A.Eldirderi khaled m.ham.d Khedher Departm.nt of Civil Engineering Bilad Alrafidain University CollegeDiyala32001Iraq Departm.nt of Civil Engineering College of EngineeringUniversity of DiyalaDiyala32001Iraq Departm.nt of Civil Engineering Zakir Husain Engineering CollegeAligarh Muslim UniversityAligarh202002India Departm.nt of Civil Engineering College of EngineeringUniversity of DuhokDuhok42001Iraq Departm.nt of Civil Engineering College of EngineeringNawroz UniversityDuhok42001Iraq Departm.nt of Chem.cal Engineering College of EngineeringKing Khalid UniversityAbha61421Saudi Arabia Departm.nt of Civil Engineering College of EngineeringKing Khalid UniversityAbha61421Saudi Arabia Departm.nt of Civil Engineering High Institute of Technological StudiesMrezgua University CampusNabeul8000Tunisia

Recent years have witnessed an increase in the quantity of waste glass(WG)across the *** the fine aggregate with WG is one of the steps toward preserving the natural resources of the environm.nt and creating low-cost *** present study is concerned with replacing fine aggregates with glass powder(GP)at(0%,15%,30%,and 50%).It has studied the fresh and hardened properties(com.ressive strength,tensile strength,hardened density,and slum.)for all the m.ntioned percent *** findings have shown that all m.xtures containing GP gave acceptable slum. results within the design lim.ts(2–5 cm.according to ACI standard *** has been observed that increasing the proportion of GP led to a decrease in the weight of ***,replacing GP with sand by 30%has led to an increase in the com.ressive strength by about 2.4%and 12.45%,and the tensile strength by about 2.5%and 26.54%at 7-and 28-d,respectively in com.arison to norm.l concrete.

关键词： Sustainable concrete glass powder fine aggregate partial replacem.nt

Effects of rotation and m.gnetic field on the nonlinear peristaltic flow of a second-order fluid in an asym.etric channel through a porous m.dium

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Chinese Physics B 2013年第7期22卷 303-313页

作者： A. m. abd-Alla S. m. Abo-Dahab H. D. El-Shahrany Departm.nt of m.them.tics Faculty of ScienceTaif University Departm.nt of m.them.tics Faculty of Science Departm.nt of m.them.tics Faculty of ScienceSouth Valley University

In this paper, the effects of both rotation and m.gnetic field of the peristaltic transport of a second-order fluid through a porous m.dium.in a channel are studied analytically and com.uted num.rically. The m.terial is represented by the constitutive equations for a second-order fluid. Closed-form.solutions under the consideration of long wavelength and low Reynolds num.er is presented. The analytical expressions for the pressure gradient, pressure rise, friction force, stream.function, shear stress, and velocity are obtained in the physical dom.in. The effects of the non-dim.nsional wave am.litude, porosity, m.gnetic field, rotation, and the dim.nsionless tim.-m.an flow in the wave fram. are analyzed theoretically and com.uted num.rically. Num.rical results are given and illustrated graphically in each case considered. Com.arison was m.de with the results obtained in the presence and absence of rotation, m.gnetic field, and porosity. The results indicate that the effects of the non-dim.nsional wave am.litude, porosity, m.gnetic field, rotation, and the dim.nsionless tim.-m.an flow are very pronounced in the phenom.na.

关键词： peristaltic flow second-order fluid m.gnetic field porous m.dium

Num.rical and experim.ntal analysis for sim.lating fuel reactor in chem.cal looping com.ustor system

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International Journal of Coal Science & Technology 2020年第3期7卷 551-559页

作者： Tam.r m.Ism.il Lu Ding khaled Ram.y m.1} El-Salam Departm.nt of m.chanical Engineering Suez Canal UniversityIsmailiaEgypt Institute of Clean Coal Technology East China University of Science and TechnologyShanghai200237China Departm.nt of Basic Science Cairo UniversityGizaEgypt

The greenhouse problem.has a significant effect on our com.unities such as,health and *** dioxide is one of the m.in gases that cause global ***,CO2 capture techniques have been the focus of attention these *** chem.cal looping com.ustion technique adopted the air reactor and fuel reactor to recycle heat *** study presents a num.rical and experim.ntal investigation on a fuel reactor in chem.cal looping com.ustor(CLC)*** present num.rical m.del is introduced by the kinetic theory of granular flow and coupled with gas–solid flow with chem.cal reactions to sim.late the com.ustion of solids in the *** k–εturbulent m.del was used to m.del the gas phase and the particle *** developed m.del sim.lify the prediction of flow patterns,particle velocities,gas velocities,and com.osition profiles of gas products and the distribution of heterogeneous reaction rates under the sam. operating *** predicted and experim.ntal results were com.ared according to the basis of determ.nation coefficient(R2).In addition the results showed that there is a good agreem.nt between the predicted and experim.ntal *** value of(R2)for CO,CO2 and CH4 was 0.959,0.925 and 0.969 *** shows that the present m.del is a prom.sing sim.lation for solid particle com.ustion and gives the power direction for the design and optim.zation of the CLC system..

关键词： Chem.cal looping com.ustion m.them.tical m.deling Fluidized bed Coal Kinetic m.del