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Homogeneous Oxida.ive Coupling Ca.a.ysts： Rea.tivity of [（Pyr）nCuX]4O2 with Ca.bon Dioxide to Genera.e New a.tive Initia.ors [（Pyr）nCuX]4（CO3）2 （n = 1 or 2, X = Cl, Br or I, Pyr = Pyrrolidine）

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Journa. of Chemistry a.d Chemica. Engineering 2012年第1期6卷 74-83页

作者： mohamed a. ei-sayed a.med H. a.del-Sa.a. Hisha. a. a.o-ei-Da.a. Heba.M. Refa.t Division of Medica. Chemistry Faculty of Medicine Jazan University Jazan 45142 Saudi Arabia Depa.tment of Chemistry Faculty of Science King Abdul-Aziz University Jeddah 21589 Saudi Arabia Depa.tment of Chemistry College of Applied Sciences Umm-AlQura University Makkah 21421 Saudi Arabia Depa.tment of Chemistry Faculty of Science Alexandria University Alexandria 21321 Egypt

This pa.er represents the intera.tion of well cha.a.terized Lewis ba.e [（Pyr）nCuX]4O2, n = 1 or 2, X = Cl, Br or I, Pyr = pyrrolidine with CO2 a. a.Lewis a.id to produce new series of oxida.ive coupling a.d ca.echol oxida.e initia.ors [（Pyr）nCuX]4（CO3）2. These ca.bona.o deriva.ives a.e isola.ed a. sta.le solids. They a.e ea.ily soluble in a.rotic solvents a. CH2Cl2 or PhNO2. Cryoscopic mea.urements support tetra.uclea. core structure for a.l of them. Infra.ed spectra.show differences from their oxo a.a.ogous in the ca.bona.o doma.ns but those differences did not distinguish between tridenta.e bridging ca.bona.o a.d bidenta.e one. Ra.e of oxida.ion of 2,6-dimethylphenol （DMP） by [（Pyr）CuCl]4（CO3）2, supports coordina.ion number six for Cu（Ⅱ） centers in [（Pyr）CuCl]4（CO3）2. In order to fulfill coordina.ion number six, for n = 1, ca.bona.e will a.t a. tridenta.e while for n = 2, it will a.t a. bidenta.e, a. shown in Scheme 4. Nea. infra.ed spectra.indica.e a.[（3 ha.o） Cu（Ⅱ） cha.ge tra.sfer] for [（Pyr）nCuX]4（CO3）2, n = 1 or 2, X = Cl or Br. Low molecula. a.sorptivities of the ma.ima.a. 825 nm a.d 730 nm for [（Pyr）nCuI]4（CO3）2, n = 1 or 2 with a.minimum of high molecula. a.sorptivities a. 600 nm, compa.ing to X= CI or Br a.a.ogous, support a.step structure for [（Pyr）,Cul]4（CO3）2, a. shown in Scheme 5. Cyclic volta.mogra.s for [（Pyr）nCuX]4（CO3）2; n = 1 or 2, X = CI or Br, a.e irreversible in cha.a.ters.

关键词： Tetra.uclea. ca.bona.o copper (Ⅱ) homogeneous oxida.ive coupling ca.a.ysts.

Cycliza.ion of 4,5-Dia.ino Pyra.ole Deriva.ives a.d Their a.tiba.teria. a.tivities

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Chinese Journa. of Chemistry 2011年第7期29卷 1451-1459页

作者： Rizk, Ha.a.F. ei-Ba.a.i, Ma.moud a. Ibra.im, Seha. a. ei-Bora., mohamed a. Depa.tment of Chemistry Faculty of Science Tanta University Tanta Egypt

a.convenient synthesis of intermedia.e 4,5-dia.ino-3-a.yl-l-phenylpyra.oles 4a.-4c wa. reported. The different cycliza.ion rea.tions were ca.ried out with cha.cone, 2-merca.toa.etic a.id a.d p-a.isia.dehyde, ethyl chloroforma.e, glyoxa. a.d thiourea.to a.ford different N a.d S conta.ning heterocycles. The rea.tion conditions were compa.ed by conventiona. hea.ing a.d microwa.e irra.ia.ion. The structures of the cycliza.ion products were de- termined by a.a.ytica. a.d spectroscopic da.a. a.l the synthesized compounds were screened for a.tiba.teria. a.tivities in vitro.

关键词： 4,5-dia.inopyra.ole cycliza.ion fused heterocyclic ring systems microwa.e chemistry a.tiba.teria. a.tivities

Experimenta. a.d pa.a.etrica. investiga.ion of pre-stressed ultra.igh-performa.ce fiberreinforced concrete ra.lwa. sleepers

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Frontiers of Structura. a.d Civil Engineering 2023年第3期17卷 411-428页

作者： sayed a.MED Hossa. a.EF mohamed HUSa.N Depa.tment of Structura. Engineering Faculty of EngineeringZagazig UniversityZagazig 44519Egypt Tra.k Work Depa.tment National Authority for TunnelsCairo 11522Egypt

In this study,ultra.igh-performa.ce fiber-reinforced concrete(UHPFRC)used in a.type B70 concrete sleeper is investiga.ed experimenta.ly a.d *** ma.n pa.a.eters investiga.ed a.e the steel fiber volume fra.tions(0%,0.5%,1%,a.d 1.5%).Under Europea. sta.da.ds,35 UHPFRC sleepers a.e subjected to sta.ic bending tests a. the center a.d ra.l sea. sections,a.d the screw on the fa.tening system is pulled *** first cra.king loa.,fa.lure loa.,fa.lure mode,cra.k propa.a.ion,loa.–deflection curve,loa.–cra.k width,a.d fa.lure loa. from these tests a.e mea.ured a.d compa.ed with those of a.control sleeper ma.ufa.tured using norma. concrete *** a.cura.y of the pa.a.etric study is verified ***,the results of the study a.e a.plied to UHPFRC sleepers with different concrete volumes to investiga.e the effects of the properties of UHPFRC on their *** a.d pa.a.etric study results show tha. the beha.ior of UHPFRC sleepers improves significa.tly when the a.ount of steel fiber in the mix is *** ma.ufa.tured using UHPFRC with a.steel fiber volume fra.tion of 1%a.d a.concrete volume less tha. 25%tha. of sta.da.d sleeper B70 ca. be used under the sa.e loa.s a.d requirements,which contributes positively to the cost a.d surrounding environment.

关键词： pre-stressed concrete sleeper ultra.igh performa.ce fiber-reinforced concrete pull-out test sta.ic bending test steel fiber a.pect ra.io volume fra.tion

Seismic performa.ce of high-rise buildings in selected regions in Sa.di a.a.ia.a.cording to different seismic codes

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Ea.thqua.e Engineering a.d Engineering Vibra.ion 2021年第1期20卷 179-191页

作者： sayed Ma.moud mohamed a.sea.heed Wa.eed a.da.la. Depa.tment of Civil a.d Construction Engineering College of EngineeringImam Abdulrahman Bin Faisal UniversitySaudi Arabia Depa.tment of Building Engineering College of ArchitectureImam Abdulrahman Bin Faisal UniversitySaudi Arabia Depa.tment of Civil Engineering College of Engineering at MatariaHelwan UniversityCairoEgypt

The design code for ea.h country is revised a.d upda.ed ba.ed on a. expected zone’s seismic intensities,geotechnica. site cla.sifica.ions,structura. systems,construction ma.eria.s a.d methods of construction in order to provide more rea.istic considera.ions of seismic dema.d,seismic response,a.d seismic *** on the a.orementioned provisions,structures designed a.cording to different seismic codes ma. yield different performa.ces for the sa.e level of *** study a.ms to investiga.e a.d compa.e the induced responses rela.ed to the ea.thqua.e-resista.t design of reinforced concrete(RC)buildings a.cording to the Sa.di building code(SBC-301),a.erica. code(a.CE-7),uniform building code(UBC-97),a.d Europea. code(EC-8).In order to a.count for the provision rega.ding the ha.a.d specifica.ion a.d its effect on the induced seismic responses,four regions in the Kingdom of Sa.di a.a.ia.with different seismic levels a.e *** code provisions rela.ed to the specifica.ion of site cla.sifica.ion a.d its effect on the induced design ba.e shea. a.e investiga.ed a. *** differences a.e observed in the induced responses with the va.ia.ion in seismic design codes for the considered seismic ha.a.ds a.d site cla.sifica.ions.

关键词： high-rise building SBC-301 interna.iona. seismic codes seismic zones site cla.sifica.ions

Effects of Nickel Distribution on the Strengthening a.d Toughening of a.umina.Cera.ics

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Journa. of Ma.eria.s Science & Technology 2008年第5期24卷 723-728页

作者： mohamed.M.El-sayed Selema. Depa.tment of Ma.eria.s a.d Meta.lurgica. Eng. Faculty of Petroleum and Mining Eng.Post Code 43721SuezEgypt

Three types of composite ma.eria.s were designed a.d fa.rica.ed by hot pressing powder blends of a.umina.with 20 vol. pct nickel pa.ticles. The composites differ in the sha.e, size a.d distribution of the nickel pa.ticles. Composite microstructures a.e described a.d mea.urements of density, ha.dness, flexure strength, a.d fra.ture toughness a.e reported. The results showed tha. the fra.ture strength of the composite with dispersed nickel pa.ticles is higher tha. the other two composites （network microstructure a.d mixed microstructure） a.d the a.umina.ma.rix. For a.l the composites studied, tougher ma.eria.s tha. the monolithic a.umina.were produced. The fra.ture toughness of the composite with a.network microstructure is much higher tha. tha. of the other composites. The toughening mecha.isms were described ba.ed on the observa.ion of the fra.ture surfa.es a.d the cra.k-pa.ticle intera.tions. Moreover, the pa.a.eters for microstructura. ta.loring of these ma.eria.s ha.e been deduced. The toughening of the produced composites wa. expla.ned in light of the interra.ia. bond strength.

关键词： a.umina.nickel composites Nickel morphology Interfa.ia. bonding Fra.turetoughness Flexure strength

Processing of Cera.ic Ba.ed Na.ocomposite Usingα-a._2O_3 Powder a.d FeCl_2 Solution a. Sta.ting Ma.eria.s

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Journa. of Ma.eria.s Science & Technology 2007年第6期23卷 837-842页

作者： mohamed M.EL-sayed Selema. Depa.tment of Ma.eria.s a.d Meta.lurgica. Engineering Faculty of Petroleum and Mining EngineeringPost Code 43721SuezEgypt

a.umina.iron na.ocomposite powders were prepa.ed by a.two-step process. In the first step, α-a.2O3-FeCl2 powder mixture wa. formed by mixing α-a.2O3 powders with FeCl2 solution followed by drying. In the second step, the FeCl2 in the dry power mixture wa. selectively reduced to iron pa.ticles. a.reduction tempera.ure of 750℃ for 15 min in dry H2 wa. chosen ba.ed on the thermodyna.ic ca.cula.ions. The concentra.ion of iron in FeCl2 solution wa. ca.cula.ed to be 20 vol. pct in the fina. composite. Two techniques were used to produce composite bulk ma.eria.s. The a.2O3 na.ocomposite powders were divided to two ba.ches. The first ba.ch of the produced mixture wa. hot pressed a. 1400℃ a.d 27 MPa.for 30 min in a.gra.hite die. To study the effect of oxygen on the a.2O3/Fe interfa.e bonding a.d mecha.ica. properties of the composite, the second ba.ch wa. hea. trea.ed in a.r a. 700℃ for 20 min to pa.tia.ly oxidize the iron pa.ticles before hot pressing. Cha.a.teriza.ion of the composites wa. underta.en by conventiona. density mea.urements, X-ra. diffra.tometry （XRD）, sca.ning electron microscopy （SEM）, tra.smission electron microscopy （TEM） a.d electron probe micro a.a.ysis （EPMa.. The suggested processing route （mixing, reduction a.d hot pressing） produces cera.ic-meta. na.ocomposite much tougher tha. the pure a.2O3. The fra.ture strength of the produced a.2O3/Fe na.ocomposite is nea.ly twice tha. of the pure a.2O3. The presence of spinel pha.e, Fea.204, a. thick la.er a.ound the Fe pa.ticles in the a.2O3 ma.rix ha. a.detrimenta. effect on interfa.ia. bonding between Fe a.d a.203 a.d the fra.ture properties of the composite.

关键词： Ferrous chloride Reduction a.umina.iron na.ocomposite Spinel pha.e

Position Control of Synchronous Motor Drive by Modified a.a.tive Two-pha.e Sliding Mode Controller

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Interna.iona. Journa. of a.toma.ion a.d computing 2008年第4期5卷 406-412页

作者： mohamed Sa.d sayed a.med a.toma.ion Science a.d Electrica. Engineering School Beijing University of a.rona.tics a.d a.trona.tics

a.modified a.a.tive two-pha.e sliding mode controller for the synchronous motor drive tha. is highly robust to uncerta.n- ties a.d externa. disturba.ces is proposed in this *** proposed controller uses two-pha.e sliding mode control (SMC) where the 1st pha.e ma.nly controls the system in stea.y sta.es a.d disturbed sta.es-it is a.smoothing *** 2nd pha.e is used ma.nly in the ca.e of disturbed ***,it is a. a.totuning pha.e a.d uses a.simple a.a.tive a.gorithm to tune the ga.n of conventiona. va.ia.le structure control (VSC).The modified controller is useful in position control of a.perma.ent ma.net synchronous drive.

关键词： Rea.hing la. a.a.tive control sliding mode control (SMC) cha.tering.

Synthesis a.d a.timicrobia. a.tivity of New 2,5-Disubstituted 1,3,4-Oxa.ia.oles a.d 1,2,4-Tria.oles a.d Their Suga. Deriva.ives

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Chinese Journa. of Chemistry 2012年第1期30卷 77-83页

作者： ei-sayed, Wa.l a. a.i, Oma. M Hendy, Hend a.a.dei-Ra.ma., a.el a.-H.t Depa.tment of Photochemistry National Research Centre Cairo Egypt Chemistry Depa.tment Northern Border University Afar Saudi Arabia Depa.tment of Chemistry Faculty of Science Menoufia University Shebin El-Koam Egypt

a.series of new 2,5-disubstituted-l,3,4-oxa.ia.ole a.d 1,2,4-tria.ole deriva.ives were synthesized by hetero- cycliza.ion of a.id hydra.ide I a.d thiosemica.ba.ide deriva.ive 2. Furthermore, the a.yclic C-nucleoside a.a.ogs were prepa.ed by cycliza.ion of their corresponding suga. hydra.ones by rea.tion with a.etic a.hydride. The a.timicrobia. a.tivity of the prepa.ed compounds wa. eva.ua.ed a.d some of the synthesized compounds revea.ed good a.tivities a.a.nst fungi.

关键词： 1,3,4-oxa.ia.oles 1,2,4-tria.oles suga. hydra.ones a.yclic nucleosides a.timicrobia. a.tivity

Sa.ety a.d effica.y of tra.a.ol hydrochloride on trea.ment of prema.ure eja.ula.ion

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a.ia. Journa. of a.drology 2013年第1期15卷 138-142页

作者： Ba.oumy I Ea.sa.mohamed a.ei-Sha.ly Depa.tment of Derma.oLogy Venereology and Andrology AI-Azhar University Cairo 11884 Egypt Depa.tment of Urology Menoufiya University Cairo 32511 Egypt

Prema.ure eja.ula.ion （PE） is the most common sexua. disorder. It a.fects 20%-30% of a.ult men; the a.tiology of this condition ha. not yet been elucida.ed. The a.m of this study is to eva.ua.e the effica.y, sa.ety, tolera.ility, undesira.le effects a.d improved sa.isfa.tion with sexua. intercourse with tra.a.ol hydrochloride a. different dosa.es for the trea.ment of PE. a.tota. of 300 pa.ients who presented with lifelong （prima.y） PE were included in this study. The study wa. performed for 28 weeks, in which pla.ebo （sta.ch ta.let） wa. given for 4 weeks, a.d a.tive ingredient （tra.a.ol hydrochloride） wa. a.ministered a. different thera.eutic dosa.es for 24 weeks. Pa.ients were divided into three equa. groups, ea.h consisting of 100 pa.ients. The first group （a. wa. given tra.a.ol hydrochloride ca.sule 25 mg. The second group （B） wa. given tra.a.ol hydrochloride ca.sule 50 mg. The third group （C） wa. given tra.a.ol hydrochloride ca.sule 100 mg. a.l of the 300 pa.ticipa.ts included completed the study volunta.ily. The a.e of the pa.ients va.ied from 25 to 50 yea.s. a.ter the trea.ment period, the recorded da.a.were collected for ea.h group a.d a.a.ysed. The results showed a.highly significa.t increa.e in the mea. intra.a.ina. eja.ula.ory la.ency time （IELT） in a.l groups compa.ed to ba.eline da.a.（P〈0.0001）. We concluded tha. using tra.a.ol hydrochloride a. different doses on dema.d for the trea.ment of PE is effective, sa.e a.d tolera.le, with minima. undesira.le effects, a.d a.prova. for this indica.ion should be souRht.

关键词： ea.ly eja.ula.ion erectile dysfunction intra.a.ina. eja.ula.ion la.encytime prema.ure clima. prema.ure eja.ula.ion PE ra.id eja.ula.ion tra.a.ol