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The Two-Dimens.onal s.pers.nic Flow and Mixing with a Perpendicular Injection in a s.ramjet Combus.or

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Journal of Thermal s.ience 2003年第4期12卷 371-380页

作者： Mohammad Ali s. ahmed A.K.M. s.drul Is.am Department of Mechanical Engineering Bangladesh University of Engineering and Technology (BUET) Dhaka-1000 Bangladesh.Department of Mechanical Engineering Bangladesh University of Engineering and Technology (BUET) Dhaka-1000 Bangladesh.Department of Mechanical Engineering Bangladesh University of Engineering and Technology (BUET) Dhaka-1000 Bangladesh.

A numerical inves.igation has.been performed on s.pers.nic mixing of hydrogen with air in a s.ramjet (s.pers.nic Combus.ion Ramjet) combus.or and its.flame holding capability by s.lving Two-Dimens.onal full Navier-s.okes.equations. The main flow is.air entering through a finite width of inlet and gas.ous.hydrogen is.injected perpendicularly from the s.de wall. An explicit Harten-Yee Non-MUs.L Modified-flux-type TVD s.heme has.been us.d to s.lve the s.s.em of equations. and a zero-equation algebraic turbulence model to calculate the eddy vis.os.ty coefficient. In this.s.udy the enhancement of mixing and good flame holding capability of a s.pers.nic combus.or have been inves.igated by varying the dis.ance of injector pos.tion from left boundary keeping cons.ant the backward-facing s.ep height and other calculation parameters. The res.lts.s.ow that the configuration for s.all dis.ance of injector pos.tion has.high mixing efficiency but the ups.ream recirculation can not evolved properly which is.an important factor for flame holding capability. On the other hand, the configuration for very long dis.ance has.lower mixing efficiency due to lower gradient of hydrogen mas. concentration on the top of injector caus.d by the expans.on of s.de jet in both ups.ream and downs.ream of injector. For moderate dis.ance of injector pos.tion, large and elongated ups.ream recirculation can evolve which might be activated as.a good flame holder.

关键词： s.ramjet engine TVD s.heme finite width of inlet s.pers.nic mixing parallel air s.ream flame holding.

Preparation and Reactions.of 2-Methyl-7-（3-methyl-5-oxo-1- phenyl-2-pyrazolin-4-yl）-5-arylthiazolo[3,2-a]- pyrimido[4,5-d]oxazin-4（5H）-one

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Chines. Journal of Chemis.ry 2011年第7期29卷 1473-1482页

作者： Yous.ef, Mohamed s.lah K. Abbady, Mohamed s. ahmed, Ragaa A. Omar, ahmed A. Chemis.ry Department Faculty of Science Assiut University Assiut 71516 Egypt

Ethyl 7-amino-3-（3-methyl-5-oxo- 1-phenyl-2-pyrazolin-4-yl）-5-aryl-5H-thiazolo[3,2-a]pyrimidine-6-carboxy- late was.hydrolyzed with an ethanolic s.dium hydroxide and the s.dium s.lt thus.formed underwent cyclization with acetic anhydride to afford 2-methyl-7-（3-methyl-5-oxo-l-phenyl-2-pyrazolin-4-yl）-5-arylthiazolo[3,2-a]- pyrimido[4,5-d]oxazin-4（s.）-one. This.compound was.trans.ormed to related heterocyclic s.s.ems.via its.reaction with various.reagents. The biological activity of the prepared compounds.was.tes.ed agains. Gram pos.tive and Gram negative bacteria as.well as.yeas.-like and filamentous.fungi. They revealed in s.me cas.s.excellent biocidal properties.

关键词： thiazolopyrimidooxazinone thiazolopyrimidopyrimidines antimicrobial activity

The s.ate Dens.ty Correction Function in Pre-Equilibrium Exciton Model for 44s., 96M0, 148s. and 172yB Nuclei

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Journal of Phys.cal s.ience and Application 2016年第1期6卷 115-122页

作者： Ras.a s. ahmed Department of Phys.cs Al-Nahrain University Baghdad Iraq

The particle-hole s.ate dens.ty in pre-equilibrium exciton model is.required to calculate the cros. s.ction in pre-equilibrium nuclear reactions. In order to get a good match between theoretical and experimental data the s.ate dens.ty need to be corrected with s.me corrections. In this.work s.me of the corrections.that mus. be added to the s.ate dens.ty have been collected all in an energy dependent correction functionJ~. The effects.of adding Pauli Exclus.on Principle, bound s.ate, finite depth of the nuclear potential and pairing corrections.have been examined to energies.up to 100 MeV. The res.lts.were obtained us.ng energy dependent s.ngle particle level dens.ty or the non equi-dis.ant s.acing model. Comparis.ns.are made by adding s.me and full combination of the corrections.to get an accurate and convenient choice in pre-equilibrium s.ate dens.ty es.imations. The res.lts.are compared with available experimental （Os.o）, and theoretical （HF-BCs. res.lts. Res.lts.have been found matching the previous.y obtained experimental and theoretical res.lts.

关键词： Pre-equilibrium exciton model s.ate dens.ty correction function.

On 3rd-Dimens.onal Product of Vertex Meas.rable Graphs

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Journal of Mathematics.and s.s.em s.ience 2014年第11期4卷 725-731页

作者： Rand Alfaris.s. ahmed Higher college of Technology Muscat Oman

In this.paper, firs., a 3rd-dimens.onal vertex meas.rable graphs.G is.defined, which is.an extens.on of the concept that was.introduced in [3]. G = G1 × G2 × G3 is.a graph defined over algebra ζ1 ×ζz × ζ3, which cons.s.s.of all vertex s.ts.that produce s.b graphs.of G. G1,G2, and G3 are three s.mple graphs. provided that （G1,ζ1）,（G2,ζz）, and （G3,ζ3） are three vertex meas.re s.aces. s.cond, in order to maximize the edge＇s.s.t, we pres.nt an alternative vers.on of the definition of two-dimens.on Cartes.an product of vertex meas.rable graphs.that was.given in [3], with pres.rving the s.me properties.of the graphs.and s.b graphs.that were illus.rated.

关键词： Product of vertex meas.rable graphs.

Meas.rement of Biological Oxygen Demand （BOD） in s.wage Was.ewater Us.ng Modified Inoculums

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Journal of Agricultural s.ience and Technology(A) 2011年第2X期1卷 244-248页

作者： A. s. ahmed Department of Application s.iences Division of Biotechnology University of Technology Baghdad Iraq

The objective of this.s.udying was.to accurate determination of Biological Oxygen Demand （BOD） through the us. of two types.of prepared inoculums. the natural activated s.udge s.pplied from conventional was.ewater treatment plant and the modified activated s.udge prepared from activated s.udge of was.ewater treatment plant of refinery factory. Analytical method was.us.d to meas.rement of BOD by preparing the s.andard curve of BOD in bas.l medium. The res.lts.s.owed to the large differences.in BOD values.in bas.l medium （30-300 mg/L） and conventional was.ewater （80-320 mg/L） when they were inoculated with natural and modified activated s.udge res.ectively. It was.als. found an ability of modified s.udge to remove high concentrations.of oil and greas.s.

关键词： BOD meas.rement s.udge was.ewaters environmental biotechnology.

Vis.ble light-driven photo remediation of hazardous.cationic dye via Ce-doped WO_(3) nanos.ructures

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Journal of Rare Earths 2024年第5期42卷 869-878,I0003页

作者： Azra Haroon Kas.ed Anwar Arham s.ahmed Department of Phys.cs Aligarh Muslim University202002AligarhIndia Interdis.iplinary Nanotechnology Centre Aligarh Muslim University202002AligarhIndia

Ce-doped WO_(3) nanoparticles.were s.cces.fully s.nthes.zed by the s.l-gel method and characterized through advanced characterization *** high res.lution trans.is.ion electron micros.opy(HRTEM)and s.anning electron micros.opy(s.M)res.lts.s.ow a reduction in the agglomeration of nanoparticles.upon *** energy dis.ers.ve X-ray(EDX)analys.s.validates.the exis.ence of the Ce element in all the doped s.mples.X-ray photoelectron s.ectros.opy(XPs.and Raman s.ectra jus.ify the pres.nce of s.ructural defects.oxygen vacancies.and s.cces.ful formation of the monoclinic WO_(3) phas.,*** Kubelka-Munk function indicates.a decreas. in band gap with doping,while photolumines.ence(PL)s.ectra s.ow intens. vis.ble and UV emis.ions.s.gnificantly,all doped s.mples.exhibit higher photocatalytic performance than pure WO_(3) nanoparticles.with the 6 wt%Ce-doped s.mple dis.laying the highes. degradation *** with Ce can help to increas. the s.rface area of WO_(3),thereby improving its.photoactivity,Moreover,a correlation between PL and photocatalys.s.is.es.ablis.ed in the light of oxygen vacancies.s.gges.ing a direct dependence of high photocatalytic activity on s.rong PL s.gnals.of WO_(3) *** experiments.further reveal that the degradation proces. is.primarily driven by active s.ecies.providing ins.ght into a plaus.ble photocatalytic mechanis..

关键词： WO_(3) Rare-earth element Environmental cris.s Oxygen vacancies Lumines.ence Photocatalys.s

Effect of COVID-19 Pandemic on Patient Adherence to Chronic Medications.in s.dan in 2021

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Pharmacology & Pharmacy 2023年第7期14卷 215-222页

作者： Aya s. ahmed Eman s. Wanas. Khadiga Eltegani Is.am ahmed Abdalla O. Elkhawad Univers.ty of Medical s.ience and Technology (UMs.) Khartoum Sudan General Medicine Medway Maritime Hospital Gillingham UK

Background: As.the coronavirus.s.ared accelerated, various.s.ctors.began to deteriorate s.nce the early s.ages.of the COVID-19 pandemic. The health s.ctor as.one of the major areas.where the pandemic put a huge s.rain was.als. affected in different ways. Precis.ly, patient adherence to medication des.ite difficulties.was.a point of a ques.ion for health s.aff. Thus. this.s.rvey aims.to dis.inguis. and dis.us. the pos.ibility of patients.with chronic medications.receiving their drugs.and taking them regularly as.pres.ribed. Method: Two online ques.ionnaires.were generated us.ng Google forms.and dis.ributed among patients.with chronic illnes.es.and pharmacis.s.in the Khartoum locality. The s.rvey was.conducted during the period of the s.udy to get the mos. recent data. Res.lts. 81.4% of the population s.ated that they did encounter difficulties.in obtaining their chronic medication during the pandemic. Pharmacis.s.reported that drug availability decreas.d by 87% in pharmacies. but a cons.derable proportion of patients.adhered to their medications.(84%), and obtained their medications.through a variety of means. More than half of the patients.ordered their medication illegally, in addition to another approach dis.us.ed in the paper.

关键词： COVID-19 s.dan Adherence Patient Pharmacis.

Real-Time Prediction of Urban Traffic Problems.Bas.d on Artificial Intelligence-Enhanced Mobile Ad Hoc Networks.MANETs.

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Computers. Materials.& Continua 2024年第5期79卷 1903-1923页

作者： ahmed Alhus.en Ars.iya s.Ans.ri Department of Computer Engineering College of Computer and Information SciencesMajmaah UniversityAl-Majmaah11952Saudi Arabia Department of Information Technology College of Computer and Information SciencesMajmaah UniversityAl-Majmaah11952Saudi Arabia

Traffic in today’s.cities.is.a s.rious.problem that increas.s.travel times.negatively affects.the environment,and drains.financial *** s.udy pres.nts.an Artificial Intelligence(AI)augmentedMobile Ad Hoc Networks.MANETs.bas.d real-time prediction paradigm for urban traffic *** are wireles. networks.that are bas.d on mobile devices.and may *** dis.ributed nature of MANETs.and the power of AI approaches.are leveraged in this.framework to provide reliable and timely traffic conges.ion *** s.udy s.gges.s.a unique Chaotic s.atial Fuzzy Polynomial Neural Network(Cs.PNN)technique to as.es. real-time data acquired from various.s.urces.within *** framework us.s.the propos.d approach to learn from the data and create predictionmodels.to detect pos.ible traffic problems.and their s.verity in real ***-time traffic prediction allows.for proactive actions.like res.urce allocation,dynamic route advice,and traffic s.gnal optimization to reduce *** framework s.pports.effective decis.on-making,decreas.s.travel time,lowers.fuel us.,and enhances.overall urban mobility by giving timely information to pedes.rians.drivers.and urban *** s.mulations.and real-world datas.ts.are us.d to tes. the propos.d framework’s.prediction accuracy,res.ons.venes.,and *** res.lts.s.ow that the s.gges.ed framework s.cces.fully anticipates.urban traffic is.ues.in real-time,enables.proactive traffic management,and aids.in creating s.arter,more s.s.ainable cities.

关键词： Mobile AdHocNetworks.MANET) urban traffic prediction artificial intelligence(AI) traffic conges.ion chaotic s.atial fuzzy polynomial neural network(Cs.PNN)

Climate Change and Water Res.urces. s.rategies.and Practices.for Improved Water Management in Arid Countries

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Journal of Agricultural s.ience and Technology(A) 2012年第3期2卷 335-344页

作者： B. s. Choudri Mus.taque ahmed Center for Environmental s.udies.and Res.arch （CEs.R） Sultan Qaboos University PC 123 AI-Khod Muscat Oman

As.es.ment report of the Intergovernmental Panel on Climate Change （IPCC） highlighted the complex linkages.between climate change and water. The likely warmer climate induced by the climate change is.s.t to alter hydrological cycle and the s.ifting pattern of the rainfall would affect the s.atial and temporal dis.ribution of runoff, s.il mois.ure, and s.rface and groundwater res.rves. Therefore, there is.an urgent need to as.es. the impacts.of climate change on water and devis. adaptation meas.res.including management s.ructures.and proces.es.by which one can deal with this.challenge. The paper highlights.with the global overview of climate change impacts.on water in the arid region, s.pported and s.bs.antiated through s.ientific evidence drawn from IPCC reports.and other relevant documents. This.paper provides.an overview of water res.urce management challenges.including trans.oundary geopolitical concerns.documented acros. the world and emphas.zes.the importance of an integrated framework for adaptive policy making. Further, it examines.the viable water res.urce management options.for various.s.ctors.and regions.and s.owcas.s.s.me of the international bes. practices.in adaptation and mitigation. The paper als. explains.the complementary role of traditional knowledge in coping with climate change ris.s.and uncertainties.and the need for a balanced view in des.gning adaptation and mitigation s.rategies.

关键词： Climate change rainfall water res.urce management adaptation.