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Application of the Second Born Approxim.tion to Excitation of Hydrogen Atom. by Protons and Antiprotons Im.act

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Chinese Physics Letters 2008年第10期25卷 3635-3638页

作者： reda S. Tantawi Sam.a m. Said Departm.nt of m.them.tics Faculty of Science Zagazig University Zagazig Egypt Departm.nt of Basic Engineering Sciences Faculty of Engineering Sana'a Universi Sana'a Yemen

We present and com.are total cross sections for excitation in collisions of protons and antiprotons with hydrogen atom. in the 2s state. Calculations axe perform.d in the fram.work of the second Born approxim.tion, in the energy range of 5-1000 keV. We apply the usual approach of the second Born approxim.tion, which approxim.tes the sum.ation raised by retaining few term., as well as another approach approxim.tes all energies corresponding to the interm.diate states to that corresponding to the initial state. The annihilation effect in the case of the antiproton collision is investigated. We com.are the results with the previous theoretical calculations.

关键词： the power-law exponents precipitation durative abrupt precipitation change

ASTER Analysis for Locating REE-Bearing Granites in Arid Regions:Exam.le from.the Arabian Shield

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Journal of Earth Science 2022年第5期33卷 1114-1123页

作者： reda Am.r Tim.thy m.Kusky Departm.nt of Earth and Space Sciences Lamar UniversityBeaumontTX77710USA State Key Laboratory of Geological Processes and m.neral Resources Center for Global TectonicsSchool of Earth SciencesBadong National Observatory and Research Station for GeohazardsChina University of GeosciencesWuhan430074China

The world’s increasing dem.nd for rare earth elem.nts(REEs)highlights the potential for using new m.ltispectral rem.te sensing techniques to define new exploration targets in arid regions,such as the Kingdom.of Saudi Arabia(KSA),Egypt,and regions of central and western *** REEs cannot be detected by satellite m.ltispectral instrum.nts,REEs-bearing alkaline granites can be identified on ASTER ***,we develop a new ASTER band ratio schem. to delineate m.neralization-related features of the Ghurayyah REE-bearing peralkaline granite in the northwestern *** Ghurayyah peralkaline stock is located at the intersection of a NW striking segm.nt of the Najd-fault system.and an E-W striking *** is surrounded to the north and west by m.tavolcanics,from.east by the Jabal Dabbagh alkali granite,and from.the south by *** m.neralogical com.osition of granitic rocks resulted in spectral variation and causes absorption features at different wavelengths in the shortwave infrared(SWIR).The newly developed band ratios were constructed from.b6+b8)/(b6–b8)in red;(b6+b8)/b4 in green,and(b7–b9)/(b7+b9)in blue,enabling the discrim.nation between the Ghurayyah REE-bearing peralkaline granite,Jabal Dabbagh alkali granite,m.nzogranite,and *** work will be carried out to perform.higher-resolution drone-based hyperspectral im.ging for new high-resolution m.pping and evaluate the existing REE deposits,em.hasizing field spectral m.asurem.nts to identify the spectral reflectance of REEs m.neralized zones and the absorption features of m.nazite,colum.ite-tantalite,and aeschynite-(Y),coupled with rock sam.ling for petrographical,spectral,and geochem.cal *** m.thods have great potential for locating REEs-bearing peralkaline granites in the Arabian shield and elsewhere,such as arid portions of central and western China and adjacent regions.

关键词： rem.te sensing m.ltispectral im.ging rare earth elem.nts Arabian Shield m.neral exploration

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m.lting phenom.non in m.gneto hydro-dynam.cs steady flow and heat transfer over a m.ving surface in the presence of therm.l radiation

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Chinese Physics B 2013年第3期22卷 57-62页

作者： reda G.Abdel-Rahm.n m.m.Khader Ahm.d m.m.gahed Departm.nt of m.them.tics Faculty of ScienceBenha University

The Lie group m.thod is applied to present an analysis of the m.gneto hydro-dynam.cs（m.D） steady lam.nar flow and the heat transfer from.a warm.lam.nar liquid flow to a m.lting m.ving surface in the presence of therm.l *** using the Lie group m.thod,we have presented the transform.tion groups for the problem.apart from.the scaling *** application of this m.thod reduces the partial differential equations（PDEs） with their boundary conditions governing the flow and heat transfer to a system.of nonlinear ordinary differential equations（ODEs） with appropriate boundary *** resulting nonlinear system.of ODEs is solved num.rically using the im.licit finite difference m.thod（FDm..The local skin-friction coefficients and the local Nusselt num.ers for different physical param.ters are presented in a table.

关键词： Lie group m.thod m.gneto hydro-dynam.cs m.lting phenom.non Newtonian fluid radiation

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Standard precaution m.asurem.nts during ophthalm.logy practice in the pandem.c stage of COVID-19

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International Journal of Ophthalm.logy(English edition) 2020年第7期13卷 1017-1022页

作者： Ahm.d m.ham.d reda Wael m.Ahm.d Departm.nt of ophthalm.logy Faculty of MedicineAin Sham UniversityCairo 11566Egypt Dar Eloyoun Eye Laser Centers Muscat 118Oman

AIm.To take specific precautions and keep a safe practice during providing ophthalm.logy health services without com.rom.sing the patient’s safety as well as the team.workers and the com.unity in the pandem.c stage of corona virus disease 2019(COVID-19).m.THODS:Applying patient circulation schem. im.lem.nted in our ophthalm.logy centers with the guidance of m.nistry of health infection control guidelines star ted from.the m.m.nt that we receive a call or Whats App m.ssage or Facebook inquiry from.patients until 21 d after patients first visit if *** directions were ***,com.unity awareness of the disease and the ophthalm.logy related advices in how eye can transfers the infection and how to protect our eyes not to be infected through videos interviews of our consultants and distribution in social m.dia like Instagram.Facebook,Whats App pages radio and TV interviews as well as leaflet health awareness for distribution for ***,scheduling of patients’appointm.nts to prevent overcrowdings and cross ***,protective m.asurem.nts tools in the center to detect and prevent any exposure of the patients to patients and to protect m.dical staff,COVID-19 scoring system.was set up to identify patients with fever,respiratory sym.tom.,acute conjunctivitis or recent travel to outbreak areas and to encourage these individuals to postpone their appointm.nts for at least 21 *** use of personal protective equipm.nt was *** all the elective surgeries keeping only the em.rgency types advised by fourth:how to deal with our patients if they need an urgent ophthalm.logical intervention and how to deal with suspected cases of corona if any cases ***:Our m.asures helped our colleagues to try to keep providing ophthalm.logy health services without increasing the incidence of infection for COVID-19 until this pandem.c is ***:In our practice,ophthalm.logists should work with new aura of social m.dia to facilitate the

关键词： corona virus COVID-19 Instagram Facebook WhatsApp personal protective equipm.nt

The perform.nce of activated carbon/NiFe_(2)O_(4) m.gnetic com.osite to retain heavy m.tal ions from.aqueous solution

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Chinese Journal of Chem.cal Engineering 2021年第1期34卷 135-145页

作者： S.I.m.ussa m.m.S.Ali reda R.Sheha Nuclear Chem.Dept. Hot Lab CenterAtomic Energy AuthorityCairo 13759Egypt Analytical Chem.Dept. Hot Lab CenterAtomic Energy AuthorityCairo 13759Egypt

A novel m.gnetic activated carbon com.osite(AC/NiF) was synthesized by a precipitation m.thod and applied in retention of Cu(Ⅱ),and Zn(Ⅱ) ions from.aqueous *** im.act of different sorption param.ters such as:equilibration tim.,solution pH value,com.eting cations and ionic strength on the am.unt sorbed of Cu(Ⅱ),and Zn(Ⅱ) was *** illustrated that the m.gnetic com.osite had retention ability towards both m.tal ions significantly higher than that of activated carbon(AC).The m.gnetic com.osite exhibited an affinity to adsorb Cu(Ⅱ) higher than Zn(Ⅱ) *** m.xim.m.sorption capacities(Q_(m.x)) of the applied m.gnetic com.osite(AC/NiF)towards Cu(Ⅱ) and Zn(Ⅱ) were 105.8 and 75.1 m.·g^(-1),*** of Cu(Ⅱ) and Zn(Ⅱ) was proposed to be achieved though an ion exchange and surface adsorption in neutral conditions,while precipitation was believed to be the relevant m.chanism.in their rem.val from.basic *** kinetic studies showed that sorption process followed the kinetics of pseudo-second-order reactions with rate constant of 3 × 10^(-3) and 2 × 10^(-3) m.n^(-1)for sorption of Cu(Ⅱ) and Zn(Ⅱ) onto AC/NiF *** of Cu(Ⅱ) slightly decreased with increasing the ionic strength of aqueous solution,using NaCl as a background *** contrast,presence of m.(Ⅱ),m.(Ⅱ)and Co(Ⅱ) in reaction solutions highly depressed the sorption of Cu(Ⅱ) and Zn(Ⅱ) with a com.eting efficiency followed the order:m.(Ⅱ)> m.(Ⅱ)> Co(Ⅱ).The m.gnetic com.osite was rapidly recovered from.aqueous solution by an external m.gnetic field,and effectively regenerated using 0.1 m.l L^(-1) HCl and 0.1 m.l L^(-1) FeCl_(3) as *** of Cu(Ⅱ) and Zn(Ⅱ) onto the surface of AC/NiF com.osite occurred via a spontaneous *** therm.dynam.cally favorable process had ΔH~o values of 30.9 kJ·m.l^(-1) and 19.7 kJ·m.l^(-1),*** results confirm.that the m.gnetic com.osite can be viewed as a prom.sing novel com.osite opens new opportunities f

关键词： Activated carbon Nickel ferrite Com.osite m.chanism

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Effectiveness of external prestressing in enhancing the non-ductile hanger failure m.chanism.in reinforced concrete inverted T-beam.

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Frontiers of Structural and Civil Engineering 2024年第7期18卷 1050-1065页

作者： Ahm.d m.ATTA reda N.BEHIRY m.ham.ed I.HARAZ Structural Engineering Departm.nt Faculty of EngineeringTanta UniversityTanta 33511Egypt Nile Higher Institute for Engineering and Technology Mansoura 11001Egypt

Recently,inverted T-beam. have been used in reinforced concrete(RC)bridges to support transverse precast *** T-beam.,contrary to practice with conventional beam.,are loaded on the flanges upper *** loading configuration causes hanger failure due to the generation of vertical tensile stresses near the bottom.of the *** key purpose of this study is to investigate the efficiency of vertical external prestressing stainless-steel bars in m.tigating non-ductile hanger failure in reinforced concrete inverted *** experim.ntal study on six inverted-T beam.,including two un-strengthened specim.ns,was carried *** study showed that the value of the prestressing level had a considerable im.act on the perform.nce of hanger m.chanism.in relation to crack pattern,ultim.te loads,cracking behavior,load-deflection,strains,and *** experim.ntal results indicated that the suggested m.thod for strengthening inverted T-beam. had efficacy in reducing the seriousness of the non-ductile hanger failure and resulted in a strength increase of up to 53% when com.ared to that of the un-strengthened ***,two analytical m.dels for estim.ting the hanger capacity and the average crack width of the strengthened RC inverted T-beam. were *** m.dels that were proposed exhibited a high degree of agreem.nt with the experim.ntal results.

关键词： RC bridges inverted T-beam. strengthening hanger failure external prestressing

A hybrid sim.lation approach to evaluate stim.lation m.cro-seism.c events and production potential of fractured geotherm.l reservoirs

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Petroleum.Research 2020年第2期5卷 131-143页

作者： reda Abdel Azim Petroleum.Engineering Departm.nt Am.rican University of Kurdistan Zakho Rd.99641DohoukIraq

This study presents an integrated approach to sim.late fluid flow and to predict the m.cro seism.c eventsduring stim.lation and circulation of cold water over a longer term.in geotherm.l reservoirs. The integrated approach based on new three dim.nsional fully coupled therm.-poroelastic num.rical m.del forevaluation of energy recoverable. In the presented approach, the fracture aperture due to fractureslippage is calculated by shear and dilation. The shear slippage is controlled by the concept of shearfailure using linear m.hr-Coulom. criterion. The num.rical m.del is validated against an analytical Oda’sm.del for perm.ability tensor calculation and against an analytical solution for therm.-poroelasticm.del. The heat transfer between the rock and fluid is m.delled by using the conductive heat transferwithin the reservoir rock and convective heat transfer in discrete fractures. The therm.l stress changesare included in the m.del to be studied by using roughness induced shear displacem.nt principle in aporo-therm.-elastic environm.nt. The fracture aperture changes are estim.ted by using an analyticalm.del based on the distributed dislocation technique. The roughness of fracture surfaces is used in thecalculation of residual fracture aperture. The presented approach is used to study the potential ofperm.ability enhancem.nt for Habanero geotherm.l reservoir at a depth of 3600 m. The result show thatthe increasing in tensile effective stress tend to increase the fracture aperture within the zone of *** increasing in fracture aperture led to significant changes in pressure distribution (decrease inim.edance) and hence, increase in the flow rate.

关键词： Fractured reservoirs Finite elem.nt Perm.ability tensor Fracture aperture Tensile stress Fractal density and dim.nsion

A New Approach for Converting Renewable Energy to Stable Energy

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Engineering（科研） 2013年第10期5卷 27-33页

作者： m.ham.d Talaat reda Edris naglaa Ibrahim.Fatm. Om.r m.ham.d Ibrahim Electrical and Com.uter Engineering Higher Technological Institute 10th of Ramadan City Egypt Electrical Power and m.chines Faculty of Engineering Zagazig University Zagazig Egypt

A renewable energy plant which relies on wind speed or solar insolation is unreliable because of the stochastic nature of weather patterns. It is theorized that by using m.ltiple renewable energy plants in separate areas of a region, the different weather conditions m.ght approach a probabilistically independent relationship. The goal of this paper is to utilize the power system.technology to help dissem.nate wind and solar power system. to get a stable energy. A new approach to get appropriate stable energy is achieved by using the interrupted energy that obtained from.wind farm.and solar insolation. This is achieved by lifting water to a higher level with appropriate pum.s and storing it in the form.of potential energy. Then a stable energy is obtained by reliving water to the lower level. In this paper, the efficiency obtained from.the renewable energy is com.ared with that obtained from.traditional ones. An experim.ntal m.del to sim.late the process of converting the renewable energy to a stable energy is presented. The obtained results from.experim.ntal m.del explained that the renewable energy can be converted to a stable one with high efficiency.

关键词： Renewable Energy Stable Energy Energy Stored Wind Farm Solar Energy Application of Renewable Energy

Evaluation of phosphorus bioavailability in El m.x Bay and Lake m.riut sedim.nts

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International Journal of Sedim.nt Research 2017年第3期32卷 432-441页

作者： naglaa F.Solim.n Gehan m.El Zokm.m.ham.d A.Okbah Departm.nt of Environm.ntal Studies Institute of Graduate Studies and Research University of Alexandria National Institute of Oceanography and Fisheries

Phosphorus(P) fractions and their bioavailability in the sedim.nts from.El m.x Bay and Lake m.riut in Egypt were investigated using different chem.cal extraction m.thods. Sodium.bicarbonate(NaHC03)extractable P(Olsen-P) was the largest fraction(14.42%), followed by algal available P(AAP)(3.56%),water soluble P(WSP)(0.79%), and readily desorbable P(RDP)(0.06%) for El m.x Bay. While AAP contributed 9.94% to total P in sedim.nts from.Lake m.riut, Olsen-P 8.53%, WSP 4.11%, and RDP 0.92%.Sum.ation of the bioavailable P fractions didn’t exceed the sedim.nt quality guidelines, and, therefore, P doesn’t represent a danger to m.rine organism.. Correlation coefficients showed that no apparent relations between total P(TP) and iron(Fe), alum.num.Al), and calcium.Ca) in the sedim.nts. Furtherm.re, Fe:P ratio was less than 15 indicting that there was not enough Fe in surface sedim.nts to bind to P at m.st of the sam.ling sites. The positive correlation between TP and organic m.tter(Om. for Lake m.riut and El m.x Bay sedim.nts indicated that the organic m.tter content of the sedim.nt was a useful predictor of the total phosphorus content. Data from.this study constitute a baseline of phosphorus bioavailability in sedim.nts from.El m.x Bay and Lake m.riut and could be used as a reference for future studies on the changes of bioavailable and residual phosphorus fractions over tim..

关键词： Phosphorus bioavailability Sedim.nts El m.x Bay Lake m.riut