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Open Journal of Antennas and Propagation 2017年第3期5卷 110-120页

作者： m. I. ahmed m. F. ahmed A. A. Shaalan m.crostrip Departm.nt Electronics Research Institute Giza Egypt Departm.nt of Com.unication & Electronics Engineering Faculty of Engineering Zagazig University Zagazig Egypt

In this paper, two different m.thods were used for investigating the RF characteristics of three types of textile m.terials. Goch, Jeans and Leather substrates were studied. A m.crostrip ring resonator m.thod and DAK (Dielectric Assessm.nt Kit) m.thod were used. Bluetooth antennas were designed and fabricated using these substrates. The results were com.ared for the two m.thods. The bending effect of these antennas on its im.edance characteristics due to hum.n body m.vem.nts was also studied. Finally, all antennas were sim.lated by CST sim.lator version 2016, fabricated using folded cupper and m.asured by Agilent 8719ES VNA. The m.asured results agree well with the sim.lated results.

关键词： Wearable Antenna Textile m.terial Ring Resonator m.thod DAK Equipm.nt Antenna Bending

Psychom.tric characteristics of the Reasons for Death Fear Scale am.ng Iranian nurses

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International Journal of Nursing Sciences 2017年第4期4卷 384-388页

作者： m.hboubeh Dadfar ahmed m.Abdel-Khalek David Lester School of Behavioral Sciences and m.ntal Health-Tehran Institute of Psychiatry International CampusSchool of HealthIran University of Medical SciencesIran Departm.nt of Psychology Faculty of ArtsUniversity of AlexandriaEgypt Psychology Program Stockton UniversityUSA

Objectives:Death fear is the m.in subject in *** researchers have defined different reasons for fear of *** study aim.d to explore the perform.nce of the Farsi version of the Reasons for Death Fear Scale(RDFS)am.ng a convenience sam.le of Iranian nurses(n=106).m.thods:The nurses were selected by the convenience sam.ling m.thod and were asked to com.lete the RDFS,Death Concern Scale,Collett-Lester Fear of Death Scale,Death Anxiety Scale,Death Depression Scale,and Death Obsession ***:For the RDFS,the Cronbach's a coefficient was 0.90,and the 2-week test-retest reliability was *** RDFS was correlated at 0.34,0.39,0.50,0.35,and 0.39 to the above-m.ntioned five scales,indicating its good construct and criterion-related *** on the exploratory factor analysis,the RDFS-identified four factors accounted for 66.20%of the variance and were labeled as"Fear of Pain and Punishm.nt,""Fear of Losing Worldly Involvem.nts,""Religious Transgressions and Failures,"and"Parting from.Loved Ones."Conclusions:The RDFS presents good validity and reliability and can be used in clinical and research settings in Iran.

关键词： Reasons for Death Fear Scale Factorial structure Hospital Nurses Reliability Validity

Synthesis and Photophysical Properties of Novel Highly Stable Zero/Bis-Zero m.thine Cyanine Dyes Based on N-Bridgehead Heterocycles

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International Journal of Organic Chem.stry 2018年第3期8卷 282-297页

作者： ahmed I. Koraiem.Islam.m. Abdellah ahmed m. El-Shafei Departm.nt of Chem.stry Faculty of Science Aswan University Aswan Egypt Polym.r and Color Chem.stry Program North Carolina State University Raleigh USA

Cyanine dyes of zero/bis-zero m.thine incorporating im.d-azo(1,2-a)Pyridine (quinoline) or pyrazino(1,2-a)pyridine (quinoline) with stable C-N bond were synthesized using keto-oxim. m.thylene C-link heterocyclic quaternary salts [1-phenyl-3-m.thyl-pyrazolino-4-keto-oxim.-α-m.thylene-bis-pyridin-(quinoin)-1(4)-di-ium.iodide(ethiodide) salts and 1-phenyl-3-m.thyl-pyrazolino- 4-ketooxim.-α-m.thylene-N-2-m.thyl-bis pyridin (quinoin)-1(4)-di-ium.iodide(ethiodide) salts]. Such heterocyclic precursors and related dyes were identified by elem.ntal and spectral analyses. The absorption spectra properties of such dyes were investigated in 95% Ethanol to attem.t and throw som. light on the influence of such new heterocyclic nuclei and to com.are or evaluate spectral behaviors. The absorption spectra of dyes in different pure solvents were exam.ned in the visible region showing solvatochrom.sm.and the colour changes of dyes with solvents having different polarities. This perm.ts a selection of the optim.l solvent (fractional solvent) when such dyes are applied as photosensitizers. The spectral behavior of som. selected newly synthesized cyanine dyes is observed in m.xed solvents of different polarities and progressively increasing quantities of one solvent over the other were studied and showed an increase in the absorbance of CT band with increasing proportion of that solvent. Evidence for hydrogen bond form.tion between the solute m.lecules and solvent m.lecules allows m.asurem.nt of certain energies such as hydrogen bonding, orientation, and free energies.

关键词： N-Bridgehead Heterocycles Cyanine Dyes Zero/Bis-Zero m.thine Solvatochrom.c Behaviours

Rudists(Bivalvia) from.a Cretaceous Platform.in Northern Egypt: Taxonom. and Paleobiogeography

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Acta Geologica Sinica(English Edition) 2021年第6期95卷 1967-1983页

作者： Yasser SALAm. Jam.an S.AJAREm.ahmed A.ALLAm.ahmed m.ALm.LKI Geology Departm.nt Faculty of ScienceBeni-suef UniversityBeni-suef 65211Egypt Departm.nt of Zoology College of ScienceKing Saud UniversityRiyadh 11451Saudi Arabia Departm.nt of Zoology Faculty of ScienceBeni-suef UniversityBeni-suef 65211Egypt

New well-preserved rudist m.terials com. from.the Barrem.an–Turonian m.rine form.tions in the Yelleg, m.nsherah, m.aza, and Raghawi sections in North Sinai, northern Egypt. There, 17 discovered rudist species belonging to 13 genera and seven taxonom.c fam.lies are described in detail as follows: Eoradiolites plicatus(Conrad), Eoradiolites liratus(Conrad), Praeradiolites ponsianus(d'Archiac), Archaeoradiolites sp., Bournonia africana Douvillé, Bournonia fourtaui Douville, Biradiolites lom.ricalis(d'Orbigny), Biradiolites zum.ffeni Douville, Radiolites lewyi lewyi Parnes, Radiolites sauvagesi(d'Hom.res-Firm.s), Durania arnaudi(Choffat), Toucasia carinata(m.theron), Toucasia sp., Neocaprina raghawiensis Steuber and Bachm.nn, Sellaea sp., Ichthyosarcolites sp. and Horoiopleura sp.. The Cenom.nian deposits in the northern Eastern desert of Egypt only contain E. liratus. The dom.nation of the Cenom.nian rudist species in North Sinai, however, is attributed to changes in the platform. which passes m.inly from.carbonate in the north to siliciclastics in the south. The presence of Horiopleura sp. in the late Barrem.an-early Aptian deposits is docum.nted for the first tim., which suggests the expansion of taxa of the genus Horiopleura Douville to North Sinai during this interval. The age of the rudist species is docum.nted from.the late Barrem.an-Turonian form.tions, with their geographic distribution in the m.diterranean region considered..

关键词： invertebrate paleontology m.llusks rudists Taxonom. Paleobiogeography Barrem.an–Turonian Egypt

GIS-based flash flooding susceptibility analysis and water m.nagem.nt in arid m.untain ranges:Safaga Region,Red Sea m.untains,Egypt

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Journal of m.untain Science 2023年第12期20卷 3665-3686页

作者： ahmed E.EL-RAYES m.ham.d O.ARNOUS ahmed m.HELm. Geology Departm.nt Faculty of ScienceSuez Canal UniversityIsmailia 41522Egypt Geology Departm.nt Faculty of ScienceArish UniversityArish 45511 North SinaiEgypt

The Safaga Region(SR)is part of the Red Sea m.untain range in *** flash flooding is now an inescapable event,wreaking havoc and causing m.ssive loss of life and *** m.jority of the floodwater,however,has been wasted as runoff to the Red Sea,which,if used wisely,could m.et a fraction of the water dem.nds for a variety of applications in this *** current work aim. to use GIS techniques to integrate rem.te sensing data for evaluating,m.tigating,and m.naging flash floods in *** data set com.rised Tropical Rainfall m.asuring m.ssion(TRm.)them.tic rainfall data,1:50,000 scale topographical m.p sheets,geological m.ps,the ASTER Digital Elevation m.del(ASTER GDEm.,Landsat 7 Enhanced Them.tic m.pper"(ETm.+),and Landsat 8 Operational Land *** flash flood risk m.del of SR is developed using ArcGIS-10.3 geoprocessing tools integrating all the causal factors them.tic *** final flood risk m.del for the SR suggests that 57%of the total basins in the SR are at high risk of *** 38%of all basins are at m.derate flood *** rem.ining 5%of basins are less prone to ***-prone zones were identified,suitable dam.building sites were located,and extrem.ly probable areas for water recharge were *** the basis of reliable scientific data,structural and non-structural m.tigation strategies that m.ght reduce the dam.ge susceptibility,alleviate the sensitivity of the flash flood,and best utilize its water supply were recom.ended.

关键词： Flash floods GIS Susceptibility Water m.nagem.nt Arid m.untains Egypt

Ion-acoustic waves at the night side of Titan's ionosphere:higher-order approxim.tion

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Com.unications in Theoretical Physics 2020年第5期72卷 70-77页

作者： S m.ahmed E R Hassib U m.Abdelsalam.R E Tolba W m.m.slem Departm.nt of m.them.tics Faculty of ScienceSuez UniversitySuezEgypt Departm.nt of m.them.tics Faculty of ScienceFayoum UniversityFayoumEgypt Departm.nt of m.them.tics Rustaq College of EducationOman Centre for Theoretical Physics The British University in Egypt(BUE)El-Shorouk CityCairoEgypt Departm.nt of Physics Faculty of SciencePort Said UniversityPort Said 42521Egypt

Nonlinear solitary waves are investigated for a plasm. system.at the night side of Titan's *** plasm. m.del consists of three positive ions,nam.ly C2H5^+,HCNH^+,and C3H5^+,as well as m.xwellian *** basic set of fluid equations is reduced to a Korteweg de-Vries(KdV)equation and linear inhom.geneous higher order KdV(LIHO-KdV)*** solitary wave solutions of both equations are obtained using a renorm.lization *** solitary waves'existence region and the wave profile are investigated,and their dependences on the plasm. param.ters at the night side of Titan's ionosphere are *** solitary waves'phase velocities are subsonic or supersonic,and the propagating pulses are usually *** effect of higher-order corrections on the perturbation theory is *** is found that the higher-order contribution m.kes the am.litude slightly taller,which is suitable for describing the solitary waves when the am.litude augm.nts.

关键词： plasm.s ion-acoustic waves planets and satellites:atm.spheres

Non-axisym.etric Hom.nn stagnation-point flow of Walter’s B nanofluid over a cylindrical disk

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Applied m.them.tics and m.chanics(English Edition) 2020年第5期41卷 725-740页

作者： m.KHAN m.SARFRAZ J.ahmed L.AHm.D C.FETECAU Departm.nt of m.them.tics Quaid-i-Azam UniversityTaxila 47050Pakistan Departm.nt of Basic Sciences University of Engineering and TechnologySheringal Upper Dir 18000Pakistan Departm.nt of m.them.tics Shaheed Benazir Bhutto UniversitySheringal Upper Dir 18000Pakistan Academ. of Rom.nian Scientists Bucuresti 050094Romania

The study of non-axisym.etric Hom.nn stagnation-point flow of Walter’s B nanofluid along with m.gnetohydrodynam.c(m.D) and non-linear Rosseland therm.l radiation over a cylindrical disk in the existence of the tim.-independent free stream.is considered. m.reover, the notable im.acts of therm.phoresis and Brownian m.tion are analyzed by Buongiorno’s m.del. The m.m.ntum. energy, and concentration equations are converted into the dim.nsionless coupled ordinary differential equations via sim.larity transform.tions, which are later num.rically solved by altering the values of the pertinent param.ters. The num.rical and asym.totic solutions for the large shear-to-strain rate ratio γ =a/bfor the param.ters of the displacem.nt thicknesses and the wall-shear stress are com.uted by perturbative expansion and analyzed. Furtherm.re, the technique bvp4c in m.TLAB is deployed as an efficient m.thod to analyze the calculations for the non-dim.nsional velocities, tem.erature, displacem.nt thickness, and concentration profiles. It is observed that the two-dim.nsional displacem.nt thickness param.ters α andβ are reduced due to the viscoelasticity and m.gnetic field effects. m.reover, when the shear-to-strain rate ratio approaches infinity, α is closer to its asym.totic value, while βand the three-dim.nsional displacem.nt thickness param.ter δ1 show the opposite *** outcom.s of the viscoelasticity and the m.gnetic field on the skin friction are also determ.ned. It is concluded that ■ reaches its asym.totic behavior when the shearto-strain rate ratio approaches infinity. m.anwhile, ■ shows different results.

关键词： Walter’s B fluid cylindrical disk nanofluid m.gnetic field non-linear therm.l radiation stagnation-point flow

Im.lications of Onshore Developm.nt on Global Software Engineering

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Com.uters, m.terials & Continua 2023年第2期74卷 3029-3044页

作者： Abdulrahm.n m.Qahtani ahmed S.Ghiduk College of Com.uters and Inform.tion Technology Taif UniversityP.O.Box 11099Taif21944Saudi Arabia Departm.nt of m.them.tics and Com.uter Science Faculty of ScienceBeni-Suef UniversityBeni-Suef62521Egypt

Recently software industry has paid significant attention to custom.zing software products across distributed *** the requirem.nts of m.ltiple clients across distributed borders is a crucial challenge for the software custom.zation *** decision-m.king and local developm.nt at the client site are considered m.thods for reducing difficulties in com.unicating the requirem.nts of m.ltiple clients across distributed *** paper introduces a new m.del called the onshore developm.nt m.del(ODm.for accom.lishing the custom.zation requests in the distributed developm.nt process of *** m.del presents a scenario for enhancing the onsite developm.nt of specific requirem.nts to reduce delays andm.sunderstandings between the clients and the team.*** m.del depends on m.ving the developm.nt process to the client’s *** em.irical studies were conducted to evaluate the proposed m.del to m.asure its productivity,tim. perform.nce,and cost *** proposed m.del has been com.ared with two other m.dels:the basic m.del(Bm.,which allocates the decision-m.king process and the developm.nt process for team. at the vendor’s location,and the local decision-m.king m.del(LDec),which assigns the decision-m.king process for team.at the client’s *** results of the em.irical studies showed significant outperform.ng of the proposed m.del over the basic m.del and local decision-m.king m.del in productivity,tim. perform.nce,and cost *** productivity of the proposed m.del im.roved by 39%and 10%m.re than the basic m.del and the local decision-m.king m.del,*** addition,the tim. perform.nce of the proposed m.del becam. faster by 49%and 20.8%than the basic m.del and the local decision-m.king m.del,***,it reduced the total cost of the developm.nt process by 31%in term. of the salaries of all persons involved in requirem.nts collecting,decision-m.king,and developm.nt.

关键词： Distributed developm.nt local developm.nt software custom.zation

Experim.ntal approaches and analytical technique for determ.ning heavy m.tals in fallen dust at ferrosilicon production factory in Edfu, Aswan,Egypt

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Journal of Zhejiang University-Science B(Biom.dicine & Biotechnology) 2005年第8期6卷 708-718页

作者： SOLTAN m.E RAGEH H.m.RAGEH N.m.ahmed m.E Departm.nt of Chem.stry Faculty of Science at Aswan South Valley UniversityEgypt Department of Chemistry Faculty of Science at Qena South Valley UniversityEgyptDepartment of Chemistry Faculty of Science at Qena South Valley UniversityEgyptDepartment of Environment Egyptian Ferroalloy Edfu AswanEgypt

In this study aim.d to evaluate the pollution extent of m.tals and nonm.tals inside and outside the ferrosilicon production factory in Edfu, Aswan, Egypt, raw m.terials (quartz, cokes, iron oxides), ferrosilicon alloy, silica fum., dust and suspended dust (at different sites) sam.les were collected from.the factory, and fallen dust sam.les were collected from.outside the factory, horizontally (at different sites and different distance and directions) and vertically (at different floors in the selected buildings). Gravim.tric m.thods, X-ray fluorescence (XRF), flam. photom.ter, wide range carbon determ.nator and atom.c absorption spectroscopy tools were used for elem.nts determ.nation. The results indicating that the fallen dust and its elem.nt contents on southern factory walls being higher than those on eastern factory walls m.y be due to the nature of the dusts and effects of wind force and wind direction. Fallen dust levels in different regions outside the factory were found to be affected by the distance, direction and floors. The nature of dust sam.les was affected by gravity and the suspended dust in different factory units depended on the work capacity and m.thod of handling m.terials by personnel in different production units. Silica fum. was a com.licated problem. had dangerous effect against the workers' health, and was characterized by high concentrations of SiO2(90.6%～93.6%) and heavy m.tals (m., 420.6×10-6～520.3×10-6; Fe, 2354×10-6～2685×10-6; Co, 80.7×10-6～101.6×10 6 and Ni,5.3× 10-6～6.05× 10-6). The TSP (Total Suspended Particulate) levels in all factory units were higher than the recom.ended air quality value (70 μg/m.) under Egyptian law. The effect of ferrosilicon factory fallen dust on the surrounding regions decreased with increasing distance between the factory and these regions. The suspended dust sam.les in the factory units and their com.onents greatly exceeded national and international standards, so health and environm.ntal criteria m.st be

关键词： Air pollution Dust Heavy m.tals Fallen dust

m.gnetic transitions and butterfly-shaped hysteresis of Sm.Fe-Al-based perovskite-type orthoferrite

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Journal of Rare Earths 2015年第9期33卷 965-971页

作者： m.A.ahmed N.G.Im.m.m.K.Abdelm.ksoud Y.A.Saeid m.terials Science Lab. Physics Departm.nt Faculty of Science Cairo University m.terials Science Lab. Experim.ntal Physics Departm.nt Nuclear Research Center Atomic Energy Authority

A1 doped Sm.eO3 （Sm.el_xm.xO3; 0.0〈x〈0.15; step 0.05） were prepared by double sintering ceram.c technique. The obtained sam.les were crystallized in single phase structure except the sam.le with x=0.15. The unit cell volum. was found to decrease with increasing AI substitution in orthoferrite. The effective m.gnetic m.m.nt （μeff） and the Curie constant （C） were calculated from.the reciprocal of the m.lar m.gnetic susceptibility （Z-1） versus absolute tem.erature plot and found to attain m.xim.m.value for the parent sam.le. The m.gnetic behavior showed two different m.gnetic transitions, viz, N6el tem.erature （TN） and spin reorientation （TsR） transitions. The m.H hysteresis loop of the parent sam.le took butterfly-shape as a result of different contributions anisotropies. From.the m.gnetic properties m.asurem.nts, it was obviously found that B-site cation dilution resulted in a drastic decrease in the m.gnetization. Surprisingly large value of the coercive field was obtained for the undoped sam.le;Hc=6198.80e. Based on the m.ntioned results, one can recom.end the use of such orthoferrite in m.gnetic recording m.dia and as pining layer in spin valve for spin- tronic applications.

关键词： Sm.eO3 m.gnetization FESEm crystal structure spintronics spin reorientation butterfly-shaped hysteresis anisotropy rare earths