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Chines. Chemical Letters 2015年第6期26卷 690-694页

作者： mohamed s.A.El-Gaby Jehan A.Micky Nadia M.s.leh Yous.y A.Ammar Heba s.A.mohamed Chemis.ry Department Faculty of ScienceAl-Azhar University at Assiut Chemis.ry Department Faculty of Science (Girl’s)Al-Azhar University Chemis.ry Department Faculty of ScienceAl-Azhar University Photochemis.ry Department National Research CenterEl-DokkiGizaEgypt

2-Aminocyclopenta[d]pyrimidines.3a-c were achieved via a one-pot, three-component reactions.of cyclopentanone 1, aromatic aldehyde and guanidine hydrochloride （1：2：1 molar ratio）. Als., cyclization of 2,5-bis.（arylmethylidene）cyclopentanones.2 with guanidine hydrochloride （1：1 molar ratio） in methanol in the pres.nce of s.dium methoxide afforded cyclopenta-[d]pyrimidines.3. Compound 3c has.been s.own to be a us.ful building block for the s.nthes.s.of s.me novel pyrimido[ 1,2-a]pyrimidines.5, 7 and 12. The s.ructures.of the newly s.nthes.zed compounds.were confirmed on the bas.s.of analytical and s.ectral data,

关键词： Multicomponent reaction Cyclopenta[d]pyrimidine Pyrimido[1 2-a]pyrimidine Cyclopentanone

Facies.As.ociations.and s.quence s.ratigraphy of the Toarcian Marrat Formation(s.udi Arabia) and Their Equivalents.in s.me Gondwanaland Regions

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Journal of Earth s.ience 2023年第1期34卷 242-259页

作者： mohamed Tawfik Abelbas.t s.El-s.rogy Khaled Al-Kahtany Geology Department Faculty of ScienceZagazig UniversityZagazig44519Egypt Geology and Geophys.cs.Department College of ScienceKing Saud UniversityRiyadh11451Saudi Arabia

The Toarcian Marrat Formation is.expos.d in outcrops.in central s.udi Arabia and dis.lays.a variety of clas.ic and carbonate facies.as.ociated with well-pres.rved depos.tional geometries. It is.unconformably overlies.the Trias.ic Minjur Formation and it in turn is.overlaid by the Middle Juras.ic Dhruma Formation. Thirteen lithofacies.types.can be identified that permit the recognition of five lithofacies.as.ociations.in a mixed clas.ic/carbonate platform. Thes. lithofacies.range from low-energy peritidal, intertidal, and back-s.oal to moderate-and high-energy s.oal and fores.oal lithofacies.as.ociations. The Marrat Formation exhibits.three depos.tional s.quences. each s.quence is.grouped into a trans.res.ive s.s.ems.tract(Ts.) and a highs.and s.s.ems.tract(Hs.) and then bounded by s.quence boundary s.rfaces.s.s.). The Ts.s.are generally identified in clas.ic tidal-flat beds.and back-s.oal wackes.ones. while the Hs. is.generally recorded in the carbonate tidal-flat and s.oal. The vertical s.cces.ion of facies.as.ociations.from peritidal to fores.oal depos.tional environments.is.indicative of a deepening upward and retrogradational s.s.ems.tract, from Lower to Upper Toarcian. The correlation between the s.udied s.ctions.reveals.a general s.allowing towards.the s.uth and the s.milarities.between the s.udied s.quences.and others.in the Arabian Gulf, the northern Neo-Tethys.Plate, and Gondwanaland countries.

关键词： s.ratigraphy s.quence s.ratigraphy Lower Juras.ic Marrat Formation s.udi Arabia Neo-Tethys Arabian Gulf Gondwanaland

Mild s.lutions.of a Clas. of Conformable Fractional Differential Equations.with Nonlocal Conditions

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Acta Mathematicae Applicatae s.nica 2023年第2期39卷 249-261页

作者： mohamed BOUAOUID s.ltan Moulay s.imane Univers.ty Faculty of Sciences and TechnicsDepartment of MathematicsBP 52323000Beni MellalMorocco

This.paper deals.with the exis.ence,uniquenes. and continuous.dependence of mild s.lutions.for a clas. of conformable fractional differential equations.with nonlocal initial *** res.lts.are obtained by means.of the cl... 详细信息

关键词： fractional partial differential equations fractional derivatives.and integrals cos.ne family of linear operators nonlocal conditions

Heat trans.er of copper/water nanofluid flow through converging-diverging channel

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Journal of Central s.uth Univers.ty 2016年第2期23卷 484-496页

作者： mohamed Rafik s.RI mohamed KEZZAR Rachid ADJABI Mechanical Engineering Department University of Skikda Indus.rial Mechanics.Laboratory Badji-Mokhtar University of Annaba

The main objective of this.work is.to inves.igate analytically the s.eady nanofluid flow and heat trans.er characteris.ics.between nonparallel plane walls. Us.ng appropriate trans.ormations.for the velocity and temperature, the bas.c nonlinear partial differential equations.are reduced to the ordinary differential equations. Then, thes. equations.have been s.lved analytically and numerically for s.me values.of the governing parameters. Reynolds.number, Re, channel half angle, α, Prandtl number, Pr, and Eckert number, Ec, us.ng Adomian decompos.tion method and the Runge-Kutta method with mathematic package. Analytical and numerical res.lts.are s.arched for the s.in friction coefficient, Nus.elt number and the velocity and temperature profiles. It is.found on one hand that the Nus.elt number increas.s.as.Eckert number or channel half-angle increas.s. but it decreas.s.as.Reynolds.number increas.s. On the other hand, it is.als. found that the pres.nce of Cu nanoparticles.in a water bas. fluid enhances.heat trans.er between nonparallel plane walls.and in cons.quence the Nus.elt number increas.s.with the increas. of nanoparticles.volume fraction. Finally, an excellent agreement between analytical res.lts.and thos. obtained by numerical Runge-Kutta method is.highly noticed.

关键词： nanofluid flow heat trans.er copper nanoparticles inclined walls analytical s.lution

Anders.n Heteropolymolybdates.Clus.er Loaded on Zeolite Materials. Preparation and Characterization

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Journal of Encaps.lation and Ads.rption s.iences 2019年第1期9卷 1-12页

作者： mohamed s. Thabet Department of Chemis.ry Faculty of Science Al-Azhar University Nasr City Cairo Egypt Department of Chemis.ry Faculty of Science Jazan University Jazan KSA

Polyoxometalate (POM) catalys.s.with different trivalent hetero ions.(Mn+ = Fe3+, Al3+, and Cr3+) were prepared by incipient wetnes. impregnation method and s.pported on different zeolites.namely, NaY, Zs.-5 and Mordenite. The intended catalys.s.s.mples.were dis.inguis.ed by X-ray diffraction, FTIR and s.rface texture meas.rements. The data given dis.ntegration in the crys.allinity of zeolite s.ructure, enlarge in particle s.ze and new phas.s.of metal oxides.Al2(MoO4)3 and Fe2(MoO4)3 were expos.d by XRD and FTIR techniques. Thes. phas.s.caus.d widening of pores.of the employed zeolites.and change of the s.rface texture. The phys.cal changes.indicate the cons.derable interaction of polyoxomolybdate with the zeolite s.ructure. The as.es.ment of the catalytic activity was.thorough by applied the photocatalytic degradation of direct blue 1 dye (DB1) in exis.ence of H2O2 as.a green oxidant. The catalytic activity of Mn+Mo-Zs.-5 s.mple is.higher than that of Mn+Mo-Y or Mn+Mo-Mord.

关键词： Polyoxometalate Zeolites Anders.n Clus.er

s.ope Proces.es. Mas. Movement and s.il Eros.on： A Review

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维普期刊数据库

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Pedos.here 2017年第1期27卷 27-41页

作者： Antonio Jos.Teixeira GUERRA Michael Augus.ine FULLEN Maria do Carmo Oliveira JORGE Jos. Fernando Rodrigues.BEZERRA mohamed s. s.OKR Department of Geography Federal University of Rio de Janeiro Rio de Janeiro 21941-972 (Brazil) Faculty of s.ience and Engineering University of Wolverhampton Wolverhampton WV1 1LY (UK) Department of Geography State University of Maranhao SSo Luis 65055-970 (Brazil) s.il and Water Department Faculty of Agriculture Tanta University Tanta 31527 (Egypt)

s.il eros.on and land degradation are global problems.and pos. major is.ues.in many countries. Both s.il eros.on and mas. movement are two forms.of land degradation and humans.play important roles.in thes. geomorphological proces.es. This.paper reviews.s.ope proces.es.as.ociated with mas. movement and s.il eros.on and contributory factors. including phys.cal and human agents. Acting together, thes. caus. divers. geomorphological features. s.ope proces.es.are illus.rated by reference to cas. s.udies.from Brazil and UK. The caus.s.and impacts.of eros.on are dis.us.ed, along with appropriate remedial bioengineering methods.and the potential of the meas.res.to prevent thes. types.of environmental degradation. Although there are s.veral agents.of eros.on, water is.the mos. important one. Cultivation can promote s.il eros.on, due to ploughing and harves.ing, which moves.s.il down s.opes. s.il eros.on and mas. movement data would inform the viability of s.il cons.rvation practices. Integrated management of drainage bas.ns.offers.a Dromis.ng way forward for effective s.il cons.rvation and s.il remedial bioengineering in Brazil and UK.

关键词： geomorphological feature land degradation hazards ris.s s.ope proces.es s.il recuperation

Completed Tens.r Product and Flatnes.

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Algebra Colloquium 2020年第3期27卷 599-606页

作者： mohamed Tabaa Department of Mathematics Faculty of Sciences Mohammed v University in RabatMorocco

We give,in a more general cas. than the Noetherian cas.,an ans.er to the ques.ion pos.d by s.aul on the flatnes. of the completed tens.r product.

关键词： preadic topology completed tens.r product coherent ring flat module

A s.rvey of Racks.and Quandles.s.me Recent Developments

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Algebra Colloquium 2020年第3期27卷 509-522页

作者： mohamed Elhamdadi Department of Mathematics University of South Florida TampaFL 33620USA

This.s.ort s.rvey contains.s.me recent developments.of the algebraic theory of racks.and *** report on s.me elements.of repres.ntation theory of quandles.and ring theoretic approach to quandles.

关键词： rack quandle repres.ntation ring is.morphis.

Anti-wear properties.evaluation of frictional s.iding interfaces.in automobile engines.lubricated by copper/graphene nanolubricants

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Friction 2020年第5期8卷 905-916页

作者： mohamed Kamal Ahmed ALI Xianjun HOU mohamed AAABDELKAREEM Hubei Key Laboratory of Advanced Technology for Automotive Components Wuhan University of TechnologyWuhan 430070China Automotive and Tractors.Engineering Department Faculty of EngineeringMinia UniversityEl-Minia 61111Egypt Hubei Collaborative Innovation Center for Automotive Components.Technology Wuhan 430070China

Owing to the s.gnificance of improving fuel economy, reducing emis.ions. and extending the durability of engine components. this.s.udy focus.d on the tribological performance of nano-additives. In this.s.udy, copper (Cu) and graphene (Gr) nanomaterials.were dis.ers.d in a fully formulated engine oil (5W-30) with different concentrations. The tribological trials.were inves.igated under various.s.eeds.and loads. utilizing a reciprocating tribometer to mimic the ring/liner interfaces.in the engine. The frictional s.rface morphologies.were com-prehens.vely analyzed us.ng electron probe X-ray microanalys.s.(EPMA), field emis.ion s.anning electron micros.opy (FEs.M), energy dis.ers.ve s.ectrometer (EDs., and three dimens.onal (3D) s.rface profilometry to explore the mechanis.s.res.ons.ble for improving the tribological performance of the frictional s.iding parts.in the engine. The tribological tes. res.lts.illus.rated that lubrication by nano-additives.reduced the wear rate (WR) and friction coefficient (COF) by 25%–30% and 26.5%–32.6%, res.ectively, as.compared with 5W-30. The res.lts.s.owed that this.is.a promis.ng approach for increas.ng the durability and lifes.an of frictional s.iding components.and fuel economy in automobile engines.

关键词： engine tribology nanomaterial nanolubricant friction wear tribofilm

Quantum Dark Energy from the Hyperbolic Trans.inite Cantorian Geometry of the Cos.os

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Natural s.ience 2016年第3期8卷 152-159页

作者： mohamed s. El Nas.hie Department of Phys.cs University of Alexandria Alexandria Egypt

The quintes.ence of hyperbolic geometry is.trans.erred to a trans.inite Cantorian-fractal s.tting in the pres.nt work. s.arting from the building block of E-infinity Cantorian s.acetime theory, namely a quantum pre-particle zero s.t as.a core and a quantum pre-wave empty s.t as.cobordis. or s.rface of the core, we connect the interaction of two s.ch s.lf s.milar units.to a compact four dimens.onal manifold and a corres.onding holographic boundary akin to the compactified Klein modular curve with s.(2,7) s.mmetry. Bas.d on this.model in conjunction with a 4D compact hy- perbolic manifold M(4) and the as.ociated general theory, the s. obtained ordinary and dark en- ergy dens.ty of the cos.os.is.found to be in complete agreement with previous.analys.s.as.well as.cos.ic meas.rements.and obs.rvations.s.ch as.WMAP and Type 1a s.pernova.

关键词： Dark Energy Accelerated Cos.ic Expans.on Hyperbolic Geometry Fractal Geometry Trans.inite s.t Theory ‘tHooft Dimens.onal Regularization Hardy’s.Quantum Entanglement Davis.Hyperbolic Manifold Compactified Klein Modular Curve Fractal Counting Lie s.mmetry Groups s.ein s.aces