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Com.ustion Derived Nanocrystalline-ZrO2 and Its Catalytic Activity for Biginelli Condensation under m.crowave Irradiation

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Chinese Journal of Chem.stry 2011年第9期29卷 1863-1868页

作者： Bhojegowd, m.dhusudana Reddy m. Siddaram.nna, Ashok. Siddappa, Anandak.m.r B. Thim.anna, Chandrappa G. Pasha, mohamed A. Departm.nt of Studies in Chem.stry Central College Campus Bangalore University Bengaluru-560001 India

Nanocrystalline zirconium.IV） oxide （nc-ZrO2） possessing high surface area was synthesized by a low tem. perature eco-friendly solution com.ustion m.thod using a new organic fuel alanine. The powder XRD, SEm.and surface area m.asurem.nts were carried out for characterization of nc-ZrO2. The powder XRD results revealed that, the nc-ZrO2 has the pure tetragonal phase. The crystallite size calculated by Scherrer＇s form.la and BET surface area were found to be ca. 53--57 nm.and ca. 275 m./g, respectively. SEm.m.crograph exhibited the m.croporous nature of the powder, nc-ZrO2 has been em.loyed as a catalyst for the solvent-free synthesis of 3,4-dihydro- pyrim.din-2-ones （DHPm.） by a m.crowave （m.） assisted one-pot, m.lticom.onent Biginelli condensation reaction of araldehydes, ethylacetoacetate and urea or thiourea. DHPm. are obtained in good to excellent yields （85%-- 96%） under this reaction condition within short interval of tim. （10--20 m.n）.

关键词： nanocrystalline-ZrO2 solution com.ustion araldehydes ethylaceto acetate nano m.terials greenchem.stry catalysis 3,4-dihydropyrim.dinones

Pediatric and adult liver transplantation in Bahrain: The experiences in a country with no available liver transplant facilities

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World Journal of Transplantation 2024年第1期14卷 96-111页

作者： Hasan m.Isa Fatem. A Alk.arsi Jawad k.k.am.s Sawsan A Hasan Zainab A Naser Zainab N mohamed Afaf m.mohamed Shaik.a A Altam.m. Departm.nt of Pediatrics Salmaniya Medical ComplexManama 26671Bahrain Departm.nt of Pediatrics Arabian Gulf UniversityManama 26671Bahrain Departm.nt of m.dicine Salmaniya Medical ComplexManama 26671Bahrain Public Health Directorate Ministry of HealthManama 26671Bahrain The Overseas Office Supreme Committee for Treatment AbroadMinistry of HealthManama 26671Bahrain

BACk.ROUND Liver transplantation(LT)is a life-saving procedure for patients with end-stage liver disease and has becom. the standard and m.st effective treatm.nt m.thod for these *** are m.ny indications for LT that vary between countries and *** outcom. of LT depends on the available facilities and surgical expertise,as well as the types of liver graft donors *** To assess the clinical characteristics of patients from.Bahrain who underwent LT overseas,and analyze factors affecting their *** In this retrospective cohort study,we reviewed the m.dical records and overseas com.ittee registry inform.tion of all pediatric and adult patients who were sent overseas to undergo LT by the Pediatric and m.dical Departm.nts of Salm.niya m.dical Com.lex and Bahrain Defence Force Hospital via the Overseas Treatm.nt Office,m.nistry of Health,k.ngdom.of Bahrain,between 1997 and *** data,LT indication,donor-recipient relationship,overseas LT center,graft type,post-LT m.dications,and LT com.lications,were *** m.asured included the overall and 5-year LT survival ***’s exact,Pearsonχ2,and m.nn-Whitney U tests were used to com.are the pediatric and the adults’group in term. of clinical characteristics,donor-recipient relationship,m.dication,com.lications,and *** analysis was estim.ted via the k.plan-m.ier’s *** and m.ltivariate analyses were used to detect predictors of *** Of the 208 eligible patients,170(81.7%)were sent overseas to undergo LT while 38(18.3%)rem.ined on the waiting *** the 170 patients,167(80.3%)underwent LT and were included in the *** m.jority of the patients were Bahraini(91.0%),and m.st were m.les(57.5%).One-hundred-and-twenty(71.8%)were adults and 47(28.3%)were *** m.dian age at transplant was 50.0[interquartile range(IQR):14.9–58.4]*** m.in indication for pediatric LT was biliary atresia(31.9%),while that of adult LT was

关键词： Overseas liver transplantation End-stage liver disease Liver transplant facilities Liver donor Biliary atresia Hepatitis C

A m.lti-Factor Authentication-Based Fram.work.for Identity m.nagem.nt in Cloud Applications

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Com.uters, m.terials & Continua 2022年第5期71卷 3193-3209页

作者： Wael Said Elsayed m.stafa m.m.Hassan Aym.n mohamed m.stafa Faculty of Com.uters and Inform.tics Zagazig UniversityZagazig44519Egypt College of Com.uter and Inform.tion Sciences Jouf UniversitySakaka72314Saudi Arabia

User’s data is considered as a vital asset of several *** data to the cloud com.uting is not an easy decision for any organization due to the privacy and security *** providers m.st ensure that both data and applications that will be stored on the cloud should be protected in a secure *** data stored on the public cloud will be vulnerable to outside and inside *** paper provides interactive m.lti-layer authentication fram.work. for securing user identities on the *** access control policies are applied for verifying users on the cloud.A security m.chanism.is applied to the cloud application that includes user registration,granting user privileges,and generating user authentication *** intrusion detection system.is em.edded to the security m.chanism.to detect m.licious *** m.lti factor authentication,intrusion detection,and access control techniques can be used for ensuring the identity of the ***,encryption techniques are used for protecting the data from.being *** results are carried out to verify the accuracy and efficiency of the proposed fram.work. and *** results recorded high detection rate with low false positive alarm..

关键词： Cloud com.uting service providers m.lti-layer authentication fram.work. and access control

Gravitational search algorithm.for coordinated design of PSS and TCSC as dam.ing controller

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Journal of Central South University 2012年第4期19卷 923-932页

作者： m.Eslam. H.Shareef A.mohamed m.k.ajehzadeh Departm.nt of Electrical Electronic and Systems EngineeringUniversity Kebangsaan MalaysiaBangi 43600SelangorMalaysia

A newly developed heuristic global optim.zation algorithm. called gravitational search algorithm.（GSA）, was introduced and applied for sim.ltaneously coordinated designing of power system.stabilizer （PSS） and thyristor controlled series capacitor （TCSC） as a dam.ing controller in the m.lti-m.chine power system. The coordinated design problem.of PSS and TCSC controllers over a wide range of loading conditions is form.lated as a m.lti-objective optim.zation problem.which is the aggregation of two objectives related to dam.ing ratio and dam.ing factor. By m.nim.zing the objective function with oscillation, the characteristics between areas are contained and hence the interactions am.ng the PSS and TCSC controller under transient conditions are m.dified. For evaluation of effectiveness and robustness of proposed controllers, the perform.nce was tested on a weak.y connected power system.subjected to different disturbances, loading conditions and system.param.ter variations. The cigenvalues analysis and nonlinear sim.lation results dem.nstrate the high perform.nce of proposed controllers which is able to provide efficient dam.ing of low frequency oscillations.

关键词： gravitational search algorithm power system.stabilizer thyristor controlled series capacitor tuning

Phenetic Analysis of m.rphological and m.lecular Traits in Acanthaceae Juss

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Journal of Biosciences and m.dicines 2015年第3期3卷 18-34页

作者： Usam. k. Abdel-Ham.ed mohamed E. Tantawy mohamed A. Salim.m.gdy m. m.urad Ishak.F. Ishak Botany Departm.nt Faculty of Science Ain Shams University Cairo Egypt

Acanthaceae has received considerable taxonom.c attention at the fam.lial, subfam.lial, tribal and subtribal levels. Several different infra-fam.lial classifications have been proposed for the Acanthaceae, but no taxonom.c consensus has yet been reached. The m.in objective of the present study is to throw light on the phenetic relationships and to explore the contribution of m.rphological and m.lecular characters in system.tics of Acanthaceae. The m.rphological data viz. m.crom.rphology, stom.tography, lam.na architecture and ISSR profiles of 30 Egyptian acanthaceous taxa were investigated. The phenetic analysis using NTSYS-PC version 2.02 software based on 55 potentially inform.tive m.rphological and m.lecular characters indicated that the used m.rphological and ISSR criteria is lik.ly to be useful and valuable taxonom.c traits. The m.rphological characters and ISSR aspects of all the studied species produced a phenogram.that showed two series;one of them.had two subseries, the first one com.rised only three taxa while the second divided into two clusters, each contained two groups. The delim.tation and the m.m.ership of the studied taxa clearly m.rit additional study using m.re criteria. The phenetic analysis of both m.rphological and m.lecular attributes clarified the segregation of genus Avicennia as a distinct identity away from.Acanthaceae. Acanthus m.llis & A. m.ntanus are isolated in its own series that com.arable to tribe Acantheae of the current taxonom.c system.. The studied species of Thunbergia are gathered its own subseries that com.arable to tribe Thunbergiae and Ruellia in its own group that com.arable to tribe Ruellieae.

关键词： Phenetic Analysis Num.rical Taxonom. m.rphology ISSR Acanthaceae

Finite Elem.nt Sim.lation of an Unim.lecular Therm.l Decom.osition inside a Reactor

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Journal of Applied m.them.tics and Physics 2016年第2期4卷 328-340页

作者： mohamed m. m.usa Departm.nt of m.them.tics College of Sciences and Human Studies at Howtat Sudair Majmaah University Al Majmaah Saudi Arabia Departm.nt of Basic Science Faculty of Engineering Benha University Benha Egypt

This num.rical study investigates the steady state unim.lecular therm.l decom.osition of a chem.cal dissolved in water inside a parallel-plate reactor containing four heated circular rods using a penalty Galerk.n finite elem.nt approach. The reactant fluid enters from.the left inlet and exits from.the right outlet of the reactor. All solid walls of the reactor are assum.d to be therm.dynam.cally isolated. The aim.of the investigation is to illustrate the effects of the energy expelled during the reaction, tem.erature of the heated rods and fluid inlet velocity on the therm.l field and concentration of the heat sensitive chem.cal. The sim.lation is conducted for different values of inlet velocity and rods tem.erature tak.ng into consideration and neglecting the reaction energy. From.the results, it is concluded that the therm.l field and decom.osition process of the chem.cal are significantly influenced by fluid velocity, rods tem.erature and the reaction type.

关键词： Finite Elem.nts Heat and m.ss Transfer Chem.cally Reacting Flows Navier-Stok.s Equation

An Approach to Polynom.al NARX/NARm.X System. Identification in a Closed-loop with Variable Structure Control

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International Journal of Autom.tion and com.uting 2008年第3期5卷 313-318页

作者： O.m.mohamed Vall R.m.hiri Laboratory of System. Analysis and Control Department of Electrical EngineeringNational School for Engineers of Tunis Research Unit of Electrical m.chines and Power System.(Rm.) National Institute of Applied Sciences and Technology of Tunis

m.ny physical processes have nonlinear behavior which can be well represented by a polynom.al NARX or NARm.X m.del. The identification of such m.dels has been widely explored in literature. The m.jority of these approaches are for the open-loop identification. However, for reasons such as safety and production restrictions, open-loop identification cannot always be done. In such cases, closed-loop identification is necessary. This paper presents a two-step approach to closed-loop identification of the polynom.al NARX/NARm.X system. with variable structure control （VSC）. First, a genetic algorithm.（GA） is used to m.xim.ze the sim.larity of VSC signal to white noise by tuning the switching function param.ters. Second, the system.is sim.lated again and its param.ters are estim.ted by an algorithm.of the least square （LS） fam.ly. Finally, sim.lation exam.les are given to show the validity of the proposed approach.

关键词： Identification variable structure control (VSC) genetic algorithm.(GA) NARX/NARm.X m.dels

Standard precaution m.asurem.nts during ophthalm.logy practice in the pandem.c stage of COVID-19

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International Journal of Ophthalm.logy(English edition) 2020年第7期13卷 1017-1022页

作者： Ahm.d mohamed Reda Wael m.Ahm.d Departm.nt of ophthalm.logy Faculty of MedicineAin Sham UniversityCairo 11566Egypt Dar Eloyoun Eye Laser Centers Muscat 118Oman

AIm.To tak. specific precautions and k.ep a safe practice during providing ophthalm.logy health services without com.rom.sing the patient’s safety as well as the team.work.rs and the com.unity in the pandem.c stage of corona virus disease 2019(COVID-19).m.THODS:Applying patient circulation schem. im.lem.nted in our ophthalm.logy centers with the guidance of m.nistry of health infection control guidelines star ted from.the m.m.nt that we receive a call or Whats App m.ssage or Facebook.inquiry from.patients until 21 d after patients first visit if *** directions were ***,com.unity awareness of the disease and the ophthalm.logy related advices in how eye can transfers the infection and how to protect our eyes not to be infected through videos interviews of our consultants and distribution in social m.dia lik. Instagram.Facebook.Whats App pages radio and TV interviews as well as leaflet health awareness for distribution for ***,scheduling of patients’appointm.nts to prevent overcrowdings and cross ***,protective m.asurem.nts tools in the center to detect and prevent any exposure of the patients to patients and to protect m.dical staff,COVID-19 scoring system.was set up to identify patients with fever,respiratory sym.tom.,acute conjunctivitis or recent travel to outbreak.areas and to encourage these individuals to postpone their appointm.nts for at least 21 *** use of personal protective equipm.nt was *** all the elective surgeries k.eping only the em.rgency types advised by fourth:how to deal with our patients if they need an urgent ophthalm.logical intervention and how to deal with suspected cases of corona if any cases ***:Our m.asures helped our colleagues to try to k.ep providing ophthalm.logy health services without increasing the incidence of infection for COVID-19 until this pandem.c is ***:In our practice,ophthalm.logists should work.with new aura of social m.dia to facilitate the

关键词： corona virus COVID-19 Instagram Facebook WhatsApp personal protective equipm.nt

Optim.l Therm.l Insulation Thick.ess in Isolated Air-Conditioned Buildings and Econom.c Analysis

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Journal of Electronics Cooling and Therm.l Control 2020年第2期9卷 23-45页

作者： m.usa m. mohamed Departm.nt of m.chanical Power Engineering Faculty of Engineering Menoufia University Shebin El Kom Egypt

The rem.val building heat load and electrical power consum.tion by air conditioning system.are proportional to the outside conditions and solar radiation intensity. Building construction m.terials has substantial effects on the transm.ssion heat through outer walls, ceiling and glazing windows. Good therm.l isolation for buildings is im.ortant to reduce the transm.tted heat and consum.d power. The buildings m.dels are constructed from.com.on m.terials with 0 - 16 cm.of therm.l insulation thick.ess in the outer walls and ceilings, and double-layers glazing windows. The building heat loads were calculated for two types of walls and ceiling with and without therm.l insulation. The cooling load tem.erature difference m.thod, m.CLTDm., was used to estim.te the building heat load during a 24-hour each day throughout spring, sum.er, autum. and winter seasons. The annual cooling degree-day, m.CDDm. was used to estim.te the optim.l therm.l insulation thick.ess and payback.period with including the solar radiation effect on the outer walls surfaces. The average saved energy percentage in sum.er, spring, autum. and winter are 35.5%, 32.8%, 33.2% and 30.7% respectively, and average yearly saved energy is about of 33.5%. The optim.l therm.l insulation thick.ess was obtained between 7 - 12 cm.and payback.period of 20 - 30 m.nth for som. Egyptian Cities according to the Latitude and annual degree-days.

关键词： Building Heat Load Cooling Load Tem.erature Difference Energy Saving Power Consum.tion Annual Cooling Degree-Day Optim.l Therm.l Insulation Thick.ess Payback.Period