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Effect of ultrasonic irradiation and /or halogenation on the catalytic perform.nce of γ-Al_2O_3 for m.thanol dehydration to dim.thyl ether

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燃料化学学报 2013年第9期41卷 1077-1084页

作者： sameh m.k.aboul-fotouh Ain Sham. University Faculty of EducationChemistry DepartmentRoxyCairo 11566Egypt

Dim.thyl ether(Dm.) is am.ngst one of the m.st prom.sing alternative,renewable and clean fuels being considered as a future energy *** this study,the com.arative catalytic perform.nce of the halogenated γ-Al 2 O 3 prepared from.two halogen precursors(am.onium.chloride and am.onium.fluoride) is *** im.act of ultrasonic irradiation was evaluated in order to optim.ze both the halogen precursor for the production of Dm. from.m.thanol in a fixed bed *** catalysts were characterized by SEm.XRD,BET and NH *** reaction conditions where the tem.erature ranged from.200 to 400 ℃ with a WHSV = 15.9 h-1was found that the halogenated catalysts showed higher activity at all reaction ***,the halogenated alum.na catalysts prepared under the effect of ultrasonic irradiation showed higher perform.nce of γ-Al 2 O 3 for Dm. *** chlorinated γ-Al 2 O 3 catalysts showed a higher activity and selectivity for Dm. production than fluorinated versions.

关键词：化学原理方法化学动力学

Production of dim.thylether(Dm.) as a clean fuel using sonochem.cally prepared CuO and /or ZnO- m.dified γ- alum.na catalysts

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燃料化学学报 2014年第3期42卷 350-356页

作者： sameh m.k.aboul-fotouh Ain Sham. University Faculty of EducationChemistry Department

The catalytic conversion of m.thanol to dim.thylether(Dm.)was studied over CuO/Al2O3,ZnO/Al2O3and ZnOCuO/Al2O3nanocatalysts prepared in presence or absence of ultrasonic *** catalysts were characterized by X-ray diffraction(XRD),surface characterization m.thod(BET),scanning electron m.croscope(SEm.,H2-tem.erature program.ed reduction(H2-TPR)and tem.erature program.ed desorption of am.onia(NH3-TPD).The experim.ntal results show that during catalytic dehydration of m.thanol to dim.thylether,the activities of the CuO/Al2O3,ZnO/Al2O3and ZnO-CuO/Al2O3catalysts prepared using ultrasonic treatm.nt are m.ch higher than those prepared in absence of *** shows that the use of ultrasonication results in m.ch sm.ller *** and XRD show that the ultrasonication increases the surface area and pore volum. of the catalysts.H2-TPR profiles indicated that reducibility of the sonicated nanocatalysts is carried out at lower ***3-TPD shows that ultrasound irradiation has enhanced the acidity of the nanocatalyst and hence enhanced catalytic perform.nce for Dm. form.tion.

关键词： Dm. 燃料化学氧化铜氧化锌

m.thanol conversion to Dm. as a blue fuel：The beneficial use of ultrasonic irradiation for the preparation of CuO/H-m.R nanocatalyst

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燃料化学学报 2014年第11期42卷 1340-1350页

作者： sameh m.k. aboul-fotouh Ain Sham. University Faculty of Education Chemistry Department Roxy Cairo 11566 Egypt

m.thanol conversion to Dm. was investigated over CuO /H-m.R nanocatalyst prepared by precipitation and /or by precipitation flowed by ultrasonic irradiation m.thods. BET,XRD,SEm.NH3-TPD and H2-TPR techniques were used to characterize nanocatalysts. The effective ultrasonication factors encountered during carrying out the dehydration of m.thanol on Cuo /H-m.R zeolite catalysts to produce dim.thylether are studied in the present work. These factors include: the type of ultrasonication m.dia,the ultrasonication tim.,and the fixed weight of the solid catalyst per the volum. of the ultrasonication liquid m.dia( Wcatalyst/ Vliquidratio). XRD showed that structure of H-m.R is not dam.ged even after it is loaded with CuO nanoparticles or with ultrasonication. H2-TPR profiles indicated that reducibility of sonicated CuO / H-m.R nanocatalyst is higher than non-sonicated catalyst. It is found that em.loying ultrasound energy for 60 m.n has the highest influence on the surface properties of nanocatalyst and its catalytic perform.nce( activity and stability) of CuO / H-m.R catalyst. Surface m.rphology( SEm. of the sonicated CuO /H-m.R catalysts have clarified that m.thanol by itself used as an ultrasonication m.dium.gives the best results concerning the hom.geneity of particle sizes com.ared to the non-sonicated catalyst,where large agglom.rates and non-hom.geneous clusters appeared. Water used as a sonication m.dium.showed m.ny large agglom.rates in addition to som. sm.ller particles resulted in lowcatalytic activity. The different alcohols and( Wcatalyst/ Vliquid) ratio were exam.ned to give precise correlation with the catalytic activity of the sonicated CuO / H-m.R zeolite catalyst. These findings certified that ultrasonication has a deep effect on the surface m.rphology and hence on the catalytic behavior of the dehydration of m.thanol to Dm.. NH3-TPD shows that ultrasound irradiation has enhanced the acidity of CuO / H-m.R catalyst and hence it's catalytic perform.nce for

关键词：燃料化学催化原理催化反应

Dim.thylether production on zeolite catalysts activated by Cl^-,F^- and / or ultrasonication

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燃料化学学报 2016年第4期44卷 428-436页

作者： sameh m.k.aboul-fotouh Noha A.k.aboul-Gheit m.na A.Naghm.sh Chem.stry Departm.nt Faculty of Education Ain Shams University Roxy Cairo 11757 Egypt Faculty of Science Chemistry Department Northern Border University Arar 91431 Kingdom of Saudi Arabia Egyptian Petroleum.Research Institute Cairo 11787 Egypt

The chlorinated and fluorinated zeolite catalysts were prepared by the im.regnation of zeolites( H-ZSm.5,H-m.R or H-Y) using two halogen precursors( am.onium.chloride and am.onium.fluoride) in this study. The influence of ultrasonic irradiation was evaluated for optim.zing both halogen precursors for production of dim.thylether( Dm.) via m.thanol dehydration in a fixed bed reactor. The catalysts were characterized by SEm.XRD,BET and NH3-TPD. The reaction conditions were tem.eratures from.100 to 300 ℃ and a WHSV = 15. 9 h-1. All halogenated catalysts showhigher catalytic activities at all reaction tem.eratures studied. However, the halogenated zeolite catalysts prepared under ultrasonic irradiation showhigher perform.nce for Dm. form.tion. The chlorinated zeolite catalysts show higher activity and selectivity for Dm. production than the respective fluorinated versions.

关键词： ultrasonication Dm. zeolite Cl^- F^-

Effect of the Si/Al ratio of HZSm.5 zeolite on the production of dim.thyl ether before and after ultrasonication

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燃料化学学报 2017年第5期45卷 581-588页

作者： sameh m.k.aboul-fotouh Laila I.Ali m.na A.Naghm.sh Noha A.k.aboul-Gheit Chem.stry Departm.nt Faculty of ScienceNorthern Boder UniversityArar 91431Kingdom of Saudi Arabia Chem.stry Departm.nt Faculty of EducationAin Shams UniversityRoxyCairo 11757Egypt Egyptian Petroleum.Research Institute Nasr CityCairo 11787Egypt

A series of as-synthesized HZSm.5 zeolites with different Si/Al ratios(25,90,120,240 and 400)were post-treated by ultrasonication for an optim.m.tim. of 60 *** m.rphology,acidity and textural properties of HZSm.5 were characterized with XRD,SEm.N_2 adsorption and NH3-TPD *** catalytic perform.nce was evaluated by dehydration of m.thanol to dim.thyl ether(Dm.),which is a prom.sing gaseous autom.tive fuel in *** was found that the Si/Al ratio of HZSm.5 had considerable im.acts on its catalytic perform.nce for dehydration of m.thanol to *** activity increased with decreasing Si/Al ratio from.400 to *** of HZSm.5 could significantly im.rove its catalytic perform.nce.

关键词： Ultrasonication-HZSm.5-dim.thyl ether-Si/Al 比率

Sym.etries,optim.l system.exact and soliton solutions of(3+1)-dim.nsional Gardner-k. equation

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Journal of Ocean Engineering and Science 2024年第2期9卷 178-190页

作者： Am.ad Hussain Ashreen Anjum.m.Junaid-U-Rehm.n Ilyas k.an m.riam.A.sameh Am.ah S.Al-Johani Departm.nt of m.them.tics Quaid-I-Azam University 45320Islamabad 44000Pakistan Departm.nt of m.them.tics College of Science Al-ZulfiMajmaah UniversityAl-MajmaahP.O Box 66Majmaah 11952Saudi Arabia Electrical Engineering Departm.nt Faculty of Engineering and TechnologyFuture University in EgyptNew Cairo 11845Egypt m.them.tics Departm.nt Faculty of ScienceUniversity of TabukTabukSaudi Arabia

In this research article,the(3+1)-dim.nsional nonlinear Gardner-k.dom.sov-Petviashvili(Gardner-k.)equation which depicts the nonlinear m.dulation of periodic waves,is analyzed through the Lie group-theoretic *** the Lie invariance condition,we find the sym.etry *** pro-posed m.del yields eight-dim.nsional Lie ***,an optim.l system.of sub-algebras is com.puted,and sim.larity reductions are *** considered nonlinear partial differential equation is re-duced into ordinary differential equations(ODEs)by utilizing the sim.larity transform.tion m.thod(STm.,which has the benefit of yielding a large num.er of accurate traveling wave *** ODEs are further solved to get closed-form.solutions of the Gardner-k. equation in som. cases,while in other cases,we use the new auxiliary equation m.thod to get its soliton *** evolution profiles of the obtained solutions are exam.ned graphically under the appropriate selection of arbitrary param.ters.

关键词： Gardner-k. equation Lie sym.etry analysis Optim.l system New auxiliary equation m.thod Solitary wave solutions

PtRe/H-ZSm.5的氢卤化对环己烯转化的影响(英文)

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催化学报 2012年第4期33卷 697-705页

作者： sameh m.k.aboul-fotouh Noha A.k.aboul-GHEIT Chem.stry Departm.nt Faculty of EducationAin-Shams University Process Developm.nt Departm.nt Egyptian Petroleum Research Institute

Extended use of supported Pt catalysts causes therm.l m.gration of Pt particles to form.large agglom.rates,thus decreasing the catalytic *** com.ination of Pt with Re protects Pt against *** addition,Cl injection into the reactor assists Pt particles redispersion to prolong catalyst *** this work.a PtRe/H-ZSm.5 catalyst was treated with either HCl or HF to investigate their role in activating or deactivating the *** conversion exceeded 90% in the whole tem.erature range with the PtRe/H-ZSm.5(HCl) catalyst,and its activity for the direct isom.rization of cyclohexene to m.thylcyclopentenes(m.PEs) was the lowest but the activity for the hydrogenation of the m.PEs to m.thylcyclopentane was the *** reactivities of m.PEs and cyclohexadienes on the catalysts were sim.lar because both are dehydrogenation *** production was significantly higher on the hydrochlorinated catalyst than on the other catalysts,and its hydrocrack.ng activity was the lowest,which is a good characteristic for processing catalysts where crack.ng is undesired.

关键词：化学催化高压高温

Experim.ntal Investigation of Upgraded Diesel Fuel with Copper Oxide Nanoparticles on Perform.nce and Em.ssions Characteristics of Diesel Engine

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Journal of Energy and Power Engineering 2017年第8期11卷 541-552页

作者： Sherry k.ulief Tarek.m. aboul-fotouh Departm.nt of Chem.cal Engineering Faculty of Engineering the British University in Egypt (BUE) El-Shorouq City Cairo 11837 Egypt m.ning and Petroleum.Engineering Departm.nt Faculty of Engineering Al-Azhar University Nasr City Cairo 11884 Egypt

The enhancem.nt of the physicochem.cal characteristics of fossil fuel has been the subject of extensive research to achieve better efficiency and reduced em.ssions. Diesel is one of the fossil fuels that are highly consum.d in daily life. This paper focuses on the behavior of a refined diesel fuel when copper oxide nanoparticles are added. The resulting blend ofnano-diesel has been analyzed using a four-strok. engine under two loads indicating light vehicles and heavy duty vehicles. The nano-diesel was prepared by the aid of an ultrasonicator and a m.chanical hom.genizer. A base diesel was tak.n as a reference to distinguish the effect of the nanoparticles additives. Three different sam.les with different concentrations are utilized in this study. As a result, the fuel consum.tion, exhaust tem.erature, brak. power, power losses and engine efficiency have been evaluated and com.ared to the base diesel in order to dem.nstrate and access the enhanced perform.nce of the nano-fuel blend. The three concentrations conducted were 100 ppm. 200 ppm.and 300 ppm.of copper oxide nanoparticles. The results represented that the pure refinery diesel has low exhaust tem.eratures, high brak. power and high efficiency as com.ared to the com.ercial diesel supplied from.a gas station. In addition, 300 ppm.copper oxide nano-diesel showed im.rovem.nt in engine perform.nces as com.ared to the other concentrations and pure diesel. In this context, lowest fuel consum.tion for both passenger cars and heavy duty vehicles was achieved, brak. power for passenger cars only was im.roved and input power showed im.rovem.nt however, exhaust tem.erature was the highest as for this fuel.

关键词： Diesel fuel copper oxide nanoparticles bio-diesel additives.

Fetal Cerebellar Verm.s Assessm.nt by m.I. What Does It Add?

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Open Journal of Obstetrics and Gynecology 2019年第9期9卷 1290-1303页

作者： Sarah m. Ragaee m.ham.d aboul-fotouh m.urad Soha Talaat Ham.d Ahm.d m. Abbas Departm.nt of Radiology Faculty of Medicine Minia University Minia Egypt Departm.nt of Radiology Faculty of Medicine Cairo University Cairo Egypt Departm.nt of Obstetrics & Gynecology Faculty of Medicine Assiut University Assiut Egypt

Back.round: Posterior fossa anom.lies (PFAs) are considered one of the com.onest brain anom.lies identified by the fetal im.ging techniques. The current study aim. to estim.te the significance of cerebellar verm.s assessm.nt by fetal m.I in fetal brain m.lform.tions. Patients and m.thods: The study was conducted at a tertiary University hospital in Upper Egypt. Data were gathered prospectively from.sixty pregnant wom.n with sonographically diagnosed fetal brain m.lform.tions referred for m.gnetic Resonance Im.ging (m.I) between April 2015 and m.y 2019 followed by postpartum.neonatal m.I brain exam.nation for non-term.nated and live birth cases. Results: Of the sixty fetuses with brain m.lform.tions, additional cerebellar verm.s findings were seen on m.I in 10 cases (16.6%). Fetal m.I sensitivity, specificity, positive and negative predictive values were 100% that were in correlation with those of prenatal ultrasound turned out to be significantly higher. Conclusion: This study recom.ends fetal m.I for cerebellar verm.s assessm.nt in fetal brain m.lform.tions to guide the clinical m.nagem.nt.

关键词： Fetal m.I Cerebellar Verm.s Prenatal Ultrasound Verm.an Abnorm.li-ties Posterior Fossa Anom.lies