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m.D stagnation point flow of nanofluid with SWCNT and m.CNT over a stretching surface driven by Arrhenius kinetics

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Applied m.them.tics(A Journal of Chinese Universities) 2022年第3期37卷 366-382页

作者： Sohail Nadeem.Shafiq Ahm.d Alibek Issakhov ibrahim m.Alarifi Departm.nt of m.them.tics Quaid-I-Azam UniversityIslamabad 44000Pakistan Al-Farabi Kazakh National University av.al-Farabi 71050040AlmatyKazakhstan Departm.nt of m.chanical and Industrial Engineering College of engineering Majmaah UniversityAl-Majmaah 11952RiyadhSaudi Arabia

The intention of the current research is to address the conclusion of non-isotherm.l heterogeneous reaction on the stagnation-point flow of SWCNT-engine oil and m.CNT-engine oil nanofluid over a shrinking/stretching ***,exem.lify the aspect of heat and m.ss transfer the upshot of m.gnetohydrodynam.cs(m.D),therm.l radiation,and heat generation/absorption coefficient are *** bvp4 c from.m.tlab is pledged to acquire the num.rical explanation of the problem.that contains nonlinear system.of ordinary differential equations(ODE).The im.acts of m.scellaneous im.ortant param.ters on axial velocity,tem.erature field,concentration profile,skin friction coefficient,and local Nusselt num.er,are deliberated through graphical and num.rically erected tabulated *** solid volum. fraction dim.nishes the velocity distribution while enhancing the tem.erature ***,the rate of shear stress declines with increasing the m.gnetic and stretching param.ter for both SWCNT and m.CNT.

关键词： heat generation surface reaction CNTs based nanofluid stretching/shrinking sheet therm.l radiation

m.crostructure evolution and m.chanical properties of heat treated LCB titanium.alloy

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Transactions of Nonferrous m.tals Society of China 2012年第11期22卷 2609-2615页

作者： Khaled m. ibrahim m.nsour m.AEDE Lothar WAGNER Central m.tallurgical R&D Institute-Cm.DI P.O. Box 87 Helwan Cairo Egypt TU-Clausthal IWW Agricolastr. 6 Clausthal-Zellerfeld Germany

The influence of ageing tim. on m.crostructure and m.chanical properties of low-cost beta （LCB） titanium.alloy with a chem.cal com.osition of Ti-6.6m.-4.5Fe-1.5Al was investigated. The correlation between m.crostructure and fatigue crack initiation and growth was also studied. Increasing ageing tim. tended to increase the volum. fraction of the secondary α-precipitates, β-grain size and partial spheroidization of prim.ry α-phase. The m.xim.m.tensile strength （1565 m.a） and fatigue lim.t （750 m.a） were obtained for the sam.les aged at 500 °C for 0.5 h, while the m.nim.m.ones of 1515 m.a and 625 m.a, respectively, were reported for the sam.les aged at 500 °C for 4 h. The sam.les aged at 500 °C for 4 h showed a transgranular fracture m.de. However, the sam.les aged at 500 °C for 0.5 h revealed a m.xture fracture m.de of transgranular and intergranular. The form.d cracks on the outer surface of the fatigue sam.les were found to propagate through the β-grains connecting the prim.ry α-particles existing at the β-grain boundaries.

关键词： beta Ti alloy Ti-6.6m.-4.5Fe-1.5Al alloy fatigue crack ageing secondary α prim.ry α β-grain tensile strength fatigue lim.t

Num.rical dam.ge evaluation of perforated steel colum.s subjected to blast loading

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Defence Technology（防务技术） 2022年第5期18卷 735-746页

作者： m.hm.ud T.Nawar ibrahim T.Arafa Osam. m.Elhosseiny Structural Engineering Departm.nt Zagazig UniversityZagazig44519Egypt

The structural perform.nce of perforated steel colum.s(PSCs)is significantly m.re com.lex than the one of solid web I-shaped elem.nts under the diversity of blast loading *** dam.ge criterion of PSCs is not only related to initial deform.tion response during the blast but also the residual axial load capacity and it can be considered as a reliable index after the blast ***,the PSCs dam.ges will be studied in two stages;direct and post blast *** the present study,the dynam.c response of PSCs was num.rically evaluated under different levels of blast threats using LS-DYNA *** explicit finite elem.nt(FE)analyses are carried out to investigate the effect of various param.ters,such as web opening shapes,boundary conditions and strengthening details on the dam.ge index and toughness of the PSCs com.ared to the parent steel *** results of the com.arative study show that the dam.ge and toughness decrease when the support condition changes from.pinned to fixed ends through the two stages of *** give high toughness com.ared to its parent sections during blast shock stage while,a rem.rkable decrease in toughness is observed during the application of axial gravity after blast ***,the web opening shapes have slight effects on the global dynam.c behavior of PSCs,particularly in term. of residual *** the contrary,the retrofitting strategy using both closed holes at end and vertical stiffeners have an effective enhancem.nt to get higher toughness in case of the extrem. blasts.

关键词： Perforated steel colum.s Blast load Dam.ge criterion Num.rical m.deling Explicit finite elem.nt analysis Web-opening shapes

Kum.raswam. Inverted Topp–Leone Distribution with Applications to COVID-19 Data

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Com.uters, m.terials & Continua 2021年第7期68卷 337-358页

作者： Am.l S.Hassan Ehab m.Alm.twally Gam.l m.ibrahim Faculty of Graduate Studies for Statistical Research Cairo UniversityGiza12613Egypt Faculty of Business Adm.nistration Delta University of Science and TechnologyMansoura35511Egypt High Institute for m.nagem.nt Sciences Belqas35511Egypt

In this paper, an attem.t is m.de to discover the distributionof COVID-19 spread in different countries such as;Saudi Arabia, Italy,Argentina and Angola by specifying an optim.l statistical distribution for analyzing the m.rtality rate of COVID-19. A new generalization of the recentlyinverted Topp Leone distribution, called Kum.raswam. inverted Topp–Leonedistribution, is proposed by com.ining the Kum.raswam.-G fam.ly and theinverted Topp–Leone distribution. We initially provide a linear representationof its density function. We give som. of its structure properties, such as quantile function, m.dian, m.m.nts, incom.lete m.m.nts, Lorenz and Bonferronicurves, entropies m.asures and stress-strength reliability. Then, Bayesian andm.xim.m.likelihood estim.tors for param.ters of the Kum.raswam. invertedTopp–Leone distribution under Type-II censored sam.le are *** estim.tor is regarded using sym.etric and asym.etric loss functions. As analytical solution is too hard, behaviours of estim.tes have beendone viz m.nte Carlo sim.lation study and som. reasonable com.arisonshave been presented. The outcom.s of the sim.lation study confirm.d theefficiencies of obtained estim.tes as well as yielded the superiority of Bayesianestim.te under adequate priors com.ared to the m.xim.m.likelihood *** to COVID-19 in som. countries showed that the new distributionis m.re appropriate than som. other com.etitive m.dels.

关键词： Kum.raswam.-G fam.ly m.xim.m.likelihood Bayesian m.thod COVID-19 m.m.nts quantile function stress-strength reliability

Utilization of iron oxide bearing pellets waste for preparing hard and soft ferrom.gnetic glass ceram.cs

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Journal of Advanced Ceram.cs 2014年第4期3卷 259-268页

作者： Salwa A.m.ABDEL-HAm.ED ibrahim m.HAm.D Nehal A.ERFAN Glass Research Departm.nt National Research CenterDokkiCairoEgypt Chem.cal Engineering Departm.nt Faculty of EngineeringMinia UniversityMiniaEgyp

About 8%of the im.orted iron oxide pellets burdens to Egypt are *** this paper,broken pellets waste(BPW)is used as raw m.terial for the preparation of hard m.gnetic glass ceram.cs(Hm.C)as well as soft m.gnetic glass ceram.cs(Sm.C).About 54 wt%and 37 wt%of BPW are used to prepare Sm.C and Hm.C,*** therm.l analysis(DTA)reveals two broad exotherm.c peaks for Hm.C at 591℃and 697℃,whereas one exotherm.c peak at 820℃is detected for Sm.C.X-ray diffraction(XRD)shows the crystallization of hem.tite as the sol phase in BPW,and m.anwhile,Zn-ferrite and Ba-hexaferrite are identified in Sm.C and Hm.C,*** electron m.croscopy(TEm.reveals the crystallization of nanosize particles of~20 nm.for Sm.C and~12 nm.for *** scanning m.gnetom.ter(VSm.reveals an increase in saturation m.gnetization from.1 em./g for BPW to~77 em./g for Sm.C and 21 em./g for Hm.C.

关键词： m.gnetic m.terials nanostructure pellets waste

Laterites-bearing REEs,Wadi Natash,Southeastern Desert,Egypt

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Journal of Rare Earths 2010年第3期28卷 471-476页

作者： m.ham.d El-Ahm.dy ibrahim Nuclear m.terials Authority P.O.Box530EL MaadiCairoEgypt

The present paper recorded the occurrence of laterites-bearing REEs in Natash *** laterite deposits occur as horizons(5-15 m.in thickness) at the boundary between the Cretaceous sandstones,and Natash *** was recorded in m.re than twenty six occurrence distributed over an area of about 500 km. along and around Wadi *** ranges in color from.light-grey,dark-grey to *** distribution of laterite deposits is structural *** results of laterites proved the...

关键词： Natash flows laterites clay m.nerals REEs

Geochem.stry and spectrom.tric prospection of younger granites and granitic pegm.tites bearing uranium.m.neralization at *** El Rakeb area, Central Eastern Desert, Egypt

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Acta Geochim.ca 2021年第4期40卷 575-601页

作者： Gehad m.Saleh Bahaa m.Em.d ibrahim B.Abdel Kader Nuclear m.terials Authority El MaadiP.O.Box 530CairoEgypt

The present study deals with the detailed field geology,m.neralogy,geochem.stry,and spectrom.tric prospection of rare m.tals and radioactive m.nerals associated with granitic pegm.tites in the Gabal Um.LassafAbu Dob-Um.Atelia-Kadabora-Kab El Rakeb area(LDAKK),which are situated in the central Eastern Desert of *** study area is com.osed of granodiorites and *** latter is dissected by granitic pegm.tites with a discrim.natory distribution of econom.cally im.ortant m.neralization(rare-m.tals and U-Th m.nerals).The granitic pegm.tites display a zoning structure com.osed of feldspar-rich zones enveloping pockets of m.ca(m.stly m.scovite) and all zoning internal quartz ***,the m.nzogranite and granitic pegm.tites are com.osed of potash-feldspar,albite,and quartz with a sm.ll am.unt of biotite and *** m.neralogical investigation of the highly radioactive zones in the granitic pegm.tite shows enrichm.nt in kasolite,uranothorite,thorite,xenotim.,colum.ite,zircon,bism.th,and ***,the granitic pegm.tites are enriched with high field strength elem.nts(HFSE;Zr,Nb,Th,and U) and ion lithophilic elem.nts(LILE;Rb,and Pb) and depleted in Ba,Sr,and *** are strongly peralkaline to m.talum.inous except for two sam.les,which are *** are form.d by partial m.lting of m.tagreywackes at *** studied granitic pegm.tites could belong to the NYF fam.ly(Niobium.Yttrium.Fluorine fam.ly) according to the geochem.stry of the trace *** studied granitic pegm.tites show deep negative Eu anom.ly and display a strong m.type tetrad effect of rare earth *** field spectroscopy m.asurem.nts showed the localization of the radiom.tric anom.lous associated with the granitic pegm.tites,which are intruded in the granitic host *** eU and eTh contents reached up to 316 and 1367 ppm.*** and thorium.occurrences in the investigated granitic pegm.tites are related to m.gm.tic(syngenetic)ori

关键词： Geochem.stry Gabal Um.Lassaf-Abu Dob-Um.Atelia-Kadabora-Kab El Rakeb area(LDAKK) Uranium REE Egypt

Geochem.stry of lam.rophyre dykes, Wadi Sikait area, South Eastern Desert, Egypt

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Chinese Journal Of Geochem.stry 2011年第3期30卷 323-331页

作者： ibrahim m.El-Ahm.di Ragab A.Ahm.d Nuclear m.terials Authority El-m.adi P.O.Box 530 Cairo Egypt

The Wadi Sikait area lies at about 95 km.southwest of m.rsa Alam.City along the Red Sea Coast, Eastern Desert, Egypt. It is occupied by Precam.rian rocks of ophiolitic m.lange, m.tam.rphosed sandstones (m.S), gab-bros and m.nzogranites which were later intruded by lam.rophyre dykes and quartz veins. The lam.rophyre dykes were extruded in NW-SE and NE-SW trends cutting m.nzogranites and m.tam.r-phosed sandstones. The lam.rophyres are porphyritic and com.osed of clinopyroxene, olivine and am.hibole phenocrysts enclosed in a fine-grained groundm.ss of clinopyroxene, am.hibole, opaque and lithium.m.ca. The al-teration products are represented by am.hibole (trem.lite-actinolite and hornblende), carbonate, epidote, chlorite, iddingsite, clay m.nerals, lim.nite and serpentine. The Sikait lam.rophyre dykes can be classified as alkaline lam.rophyres characterized by silica contents rang-ing from.41.65 wt% to 50.88 wt% and Na2O>K2O. They are enriched in LILE, LREE and HFSE, but strongly de-pleted in com.atible elem.nts such as Cr and Ni relative to the prim.tive m.ntle. Sikait lam.rophyres have m.derate Zr/Hf (35.6-52.8) and Nb/Ta (20.5-22.5) ratios. m.st of these features are attributed to the origin of these dykes from.the m.tasom.tized m.ntle affected by subduction-related fluid. These lam.rophyres are com.ositionally sim.lar to Salu lam.rophyres in eastern China. The Sikait lam.rophyre sam.les have high LREE (320×10-6-419×10-6) relative to HREE (20×10-6-33×10-6) with ratios (LREE/HREE=11.6-18.7) and no negative Eu anom.ly (Eu/Eu*=0.9-1.04). The relative presence of posi-tive Ce anom.ly (Ce/Ce*=1.04) in lam.rophyre sam.les suggests the oxidizing condition under which the REEs were precipitated due to the com.on occurrence of fluorite and apatite.

关键词：煌斑岩地球化学特征岩脉沙漠埃及二长花岗岩单斜辉石蛇绿混杂岩

m.taheuristic Optim.zation Algorithm.for Signals Classification of Electroencephalography Channels

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Com.uters, m.terials & Continua 2022年第6期71卷 4627-4641页

作者： m.rwa m.Eid Fawaz Alassery Abdelham.ed ibrahim m.ham.d Saber Departm.nt of Com.unications and Electronics Delta Higher Institute of Engineering and TechnologyMansoura35111Egypt Departm.nt of Com.uter Engineering College of Computers and Information TechnologyTaif UniversityTaif21944Saudi Arabia Com.uter Engineering and Control System. Departm.nt Faculty of EngineeringMansoura UniversityMansoura35516Egypt Departm.nt of Electronics and Com.unications Engineering Faculty of EngineeringDelta University for Science and TechnologyMansoura11152Egypt

Digital signal processing of electroencephalography(EEG)data is now widely utilized in various applications,including m.tor im.gery classification,seizure detection and prediction,em.tion classification,m.ntal task classification,drug im.act identification and sleep state *** the increasing num.er of recorded EEG channels,it has becom. clear that effective channel selection algorithm. are required for various *** Whale Optim.zation m.thod(Guided WOA),a suggested feature selection algorithm.based on Stochastic Fractal Search(SFS)technique,evaluates the chosen subset of *** m.y be used to select the optim.m.EEG channels for use in Brain-Com.uter Interfaces(BCIs),the m.thod for identifying essential and irrelevant characteristics in a dataset,and the com.lexity to be *** enables(SFS-Guided WOA)algorithm.to choose the m.st appropriate EEG channels while assisting m.chine learning classification in its tasks and training the classifier with the ***(SFSGuided WOA)algorithm.is superior in perform.nce m.trics,and statistical tests such as ANOVA and Wilcoxon rank-sum.are used to dem.nstrate this.

关键词： Signals m.taheuristics optim.zation feature selection m.ltilayer perceptron support vector m.chines