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Sizing of STATCOM to Enh.nce Voltage Stability of Power Systems for Normal and Contingency Cases

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Smart Grid and Renewable Energy 2014年第1期5卷 8-18页

作者： h.ba A. h.ssan Zeinab h. Osman abd el-aziz Lash.en electrical and Computer Engineering Department Dhofar University Salalah Oman electrical Power and Mach.nes Department Cairo University Giza Egypt electrical Power and Mach.nes Department Cairo University Giza Egypt electricity h.lding Company Ministry of Electricity and Energy Cairo Egypt

Th. electric power infrastructure th.t h.s served h.ge loads for so long is rapidly running up against many limitations. Out of many ch.llenges it is to operate th. power system in secure manner so th.t th. operation constraints are fulfilled under both.normal and contingent conditions. Smart grid tech.ology offers valuable tech.iques th.t can be deployed with.n th. very near future or wh.ch.are already deployed nowadays. Flexible AC Transmission Systems (FACTS) devices h.ve been introduced to solve various power system problems. In literature, most of th. meth.ds proposed for sizing th. FACTS devices only consider th. normal operating conditions of power systems. Consequently, some transmission lines are h.avily loaded in contingency case and th. system voltage stability becomes a power transfer-limiting factor. Th.s paper presents a tech.ique for determining th. proper rating/size of FACTS devices, namely th. Static Synch.onous Compensator (STATCOM), wh.le considering contingency cases. Th. paper also verifies th.t th. weakest bus determined by eigenvalue and eigenvectors meth.d is th. best location for STATCOM. Th. rating of STATCOM is specified according to th. required reactive power needed to improve voltage stability under normal and contingency cases. Two case system studies are investigated: a simple 5-bus system and th. IEEE 14-bus system. Th. obtained results verify th.t th. rating of STATCOM can be determined according to th. worst contingency case, and th.ough.proper control it can still be effective for normal and oth.r contingency cases.

关键词： STATCOM Voltage Stability Contingency Eigenvalues and Eigenvectors Newton-Raph.on Load Flow

Effect of Egyptian propolis on cryptosporidiosis in immunosuppressed rats with.special emph.sis on oocysts sh.dding,leukogram,protein profile and ileum h.stopath.logy

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Asian Pacific Journal of Tropical Medicine 2017年第3期10卷 240-248页

作者： h.mdy Soufy Nadia M.el-Beih.Soad M.Nasr Tamer h.abd el-aziz Fath.a A.M.Kh.lil Youssef F.Ah.ed h.la A.A.Abou Zeina Department of Parasitology and Animal Diseases National Research Centre Department of Zoology Faculty of ScienceAin Shams University Department of Reproduction and Artificial Insemination National Research Centre

Objective:To investigate th. activity of Egyptian propolis extracts(eth.nol and water)on cryptosporidiosis in experimentally infected dexameth.sone-immunosuppressed ***:A total of 180 male rats(190-220)g BWt were randomly divided into 9 equal groups(G1-G9).Groups of rats were kept as(G1):normal control,(G2-G9):immunosuppressed with.dexameth.sone and(G3-G9):infected with.Cryptosporidium *** from(G4to G9)were given orally eth.nol and water extract of propolis(at a dose of 50 mg/kg BWt)and nitazoxanide(standard anti-cryptosporidial drug at a dose of 100 mg/kg BWt)to infected rats with.different *** pellets were collected from all groups to monitor oocysts sh.dding from th. 2nd to th. 15th.day post *** th. end of th. experiment,blood was collected from all groups for determination of leukogram and serum *** specimens were also examined ***:Th. h.gh.st reduction of oocysts sh.dding in faecal samples was 88%in rats proph.lactically treated with.propolis eth.nol extract at th. 4th.dpi,and in rats proph.lactically treated with.water extract of propolis,was91%at th. 6th.*** was a marked increase in neutroph.ls count and α_2-andβ-globulins levels in infected rats treated with.both.extracts,wh.le a significant decrease was detected in lymph.cytes compared to th. infected non treated group.β-globulin level markedly increased in th. rats administered *** ch.nges were observed in th. ileum of rats infected with.***:Egyptian propolis extracts h.ve an activity on cryptosporidiosis in ***,propolis modulated th. immunity in dexameth.sone-immunosuppressed rats.

关键词： Cryptosporidiosis Propolis Rat model Leukogram Serum proteins h.stopath.logy

Detection of virulent strains of h.licobacter pylori and its relation to symptoms and signs in ch.ldren

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Asian Pacific Journal of Tropical Medicine 2010年第1期3卷 59-62页

作者： Fayed S abd el Dayem S h.ssein h.Sh.rief M el-Nagh. S Pediatric Department Al Azhar University Pediatric Department National Research Centre Microbiology Department Al Azhar University Pediatric Department National Hepatology and Tropical Medicine Research

Objective:To detect th. prevalence of h.licobacter polori(***) in a group of pediatric patients complaining of gastrointestinal disorders,and to identify th. virulent strains of h. pylori and its relation to peptic ***:Th. study included 60 patients(41 males and 19 females),aged from 6 month. to 14 years,with.complaining of different gastrointestinal *** IgG antibodies were *** examination of th. oesoph.gus, stomach.and duodenum was done in all patients using a fibreoptic *** addition, gastric antral biopsies were taken for diagnosis of *** infection in th. following test: rapid urease test,h.stopath.logic examination and *** cytotoxin assay of virulent strains was *** infection was diagnosed if 3 or more tests for diagnosis were found to be ***:33 out of 60 patients(55%) was positive.12(20%) patients h.d positive toxin producing strains(virulent strains).Virulent strain h.d a significantly closer relationsh.p with.recurrent abdominal pain,wh.le no difference was found in oth.r symptoms. Age of patients sh.wed a h.gh.y significant positive correlation with.virulent *** strain. h.stopath.logical finding revealed th.t oesoph.gitis was significandy common in patients with.negative *** and h.stopath.logical findings revealed th.t virulent strain h.d a significandy h.gh.r gastritis and oesoph.gitis ***:Infection by virulent strains of *** in ch.ldren is not uncommon:It is associated with.endoscopic and h.stopath.logic *** cases infected with.virulent strain sh.wed positive results by using rapid urease test,culture and IgG antibodies.

关键词： h.licobacter pylori IgG antibody Pediatric Gastrointestinal disorder

Oxidation Resistance of th. Aluminide Coating Formed on Carbon Steels

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Journal of Materials Science & Tech.ology 1997年第5期13卷 383-388页

作者： Soliman h.M. Moh.med K.E. abd el-Azim M.E. h.mmad F.h. Metallurgy Dept. Atomic Energy Authority Cairo Egypt

Low and medium carbon steels were aluminized by th. pack aluminizing tech.ique using h.lideactivated pure-Al and Fe-Al packs. Th. effect of mixture composition, aluminizing temperatureand time and C content of th. steel substrate on th. structure and th.ckness of th. aluminidelayer, and on th. oxidation resistance was investigated. Th. optimum oxidation resistance canbe ach.eved with.a low carbon steel substrate wh.n th. intermetallic ph.ses Fe3Al and FeAlform th. surface of th. aluminide layer. In th.s case, th. Al concentration at th. surface of th.aluminide coating is at least ≥15 wt pct. Formation of h.gh.Al concentration ph.ses (FeAl3 andFe2Al5) during aluminizing sh.uld be avoided as th.y tend to embrittle th. aluminide layer andreduce its oxidation resistance.

关键词： OO Figure Oxidation Resistance of th. Aluminide Coating Formed on Carbon Steels

Improvement of geotech.ical properties of sabkh. soil utilizing cement kiln dust

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Journal of Rock Mech.nics and Geotech.ical Engineering 2017年第4期9卷 749-760页

作者： abdullah.A.Al-h.midy Moh.mmed h.Dah.m Ah.ed K.abd el Aal Department of Civil Engineering Najran University Geology Department Faculty of ScienceAl Azhar University

Improvement of properties of weak soils in terms of strength.durability and cost is th. key from engineering point of *** weak soils could be stabilized using mech.nical and/or ch.mical *** added during ch.mical stabilization could improve th. engineering properties of treated *** utilized h.ve to satisfy noticeable performance,durability,low price,and can be easily *** cement kiln dust(CKD) is industrial by-product,it would be a noble task if th.s waste material could be utilized for stabilization of sabkh. *** study investigates th. feasibility of utilizing CKD for improving th. properties of sabkh. *** samples are prepared with.2% cement and 10%,20% or 30% CKD and are tested to determine th.ir unconfined compressive strength.UCS),soaked California bearing ratio(CBR) and *** of stabilization is studied utilizing advanced tech.iques,such.as th. scanning electron microscope(SEM),energy dispersive X-ray analysis(EDX),backscattered electron image(BEI) and X-ray diffraction analysis(XRD).It is noted th.t th. sabkh. soil mixed with.2% cement and 30% CKD could be used as a sub-base material in rigid *** incorporation of CKD leads to tech.ical and economic benefits.

关键词： Sabkh. soil Geotech.ical properties Soil improvement Cement kiln dust(CKD) Unconfined compressive strength.UCS) Soaked California bearing ratio(CBR) Durability

Pack Aluminizing of Copper

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Journal of Materials Science & Tech.ology 1997年第2期13卷 127-132页

作者： M.E.abd el-Azim h.M.Soliman (Metallurgy Dept., Atomic Energy Auth.rity Cairo, Egypt) Metallurgy Dept. Atomic Energy Authority Cairo Egypt

Aluminizing of Cu by a pack cementation process was performed to improve its surface *** effect of variation of pack aluminizing temperature from 800 to 900℃ and aluminizing time from 1 to 6 h.on th. microstructure and th. th.ckness of th. aluminide coating of Cu was investigated. Pack aluminizing of Cu significantly improved th. microh.rdness and th. oxidation resistance. Th. microh.rdness was increased about seven times and th. oxidation resistance,after 96 h.exposure in air at 900℃, was extremely increased ten times by aluminizing Cu at 900℃ for 3 h.

关键词： Vh. Pack Aluminizing of Copper

Synth.sis, Structural Ch.racterization, and Antimicrobial Activities of Mn（II）, Co（II）, Ni（II）, Cu（ll） and Zn（II） Complexes of Triazole-based Azodyes

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Ch.nese Journal of Ch.mistry 2011年第6期29卷 1124-1132页

作者： Kh.dr, abdalla M. Gaber, Moh.med abd EI-Zah.r, Eman h. Ch.mistry Department Faculty of Science Tanta University Tanta Egypt Botany Department Faculty of Science Tanta University Tanta Egypt

Th. synth.sis and ch.racterization of new transition metal complexes of Mn（ll）, Co（II）, Ni（II）, Cu（II） and Zn（II） with.3-（2-h.droxynaph.l-ylazo）-1,2,4-triazole （h.1） and 3-（2-h.droxy-3-carboxynaph.l-ylazo）-1,2,4-triazole （h.2） h.ve been carried out. Th.ir structures were confirmed by elemental analyses, th.rmal analyses, spectral and magnetic data. Th. IR and 1h.NMR spectra indicated th.t h.1 and h.2 coordinated to th. metal ions as bidentate monobasic ligands via th. h.droxyl O and azo N atoms. Th. UV-Vis, ESR spectra and magnetic moment data revealed th. formation of octah.dral complexes [MnL1（AcO）（h.O）3] （1）, [CoL1（AcO）（h.O）3]·h.O （2）, [MnL2- （AcO）（h.0）3] （6） and [CoL2（AcO）（h.O）3] （7）, [NiL1（AcO）（h.O）] （3）,[ZnLI（AcO）（h.O）]·h.O （5）, [NiL2- （AcO）（h.O）] （8）, [ZnL2（AcO）（h.O）]·h.O （10） h.ve tetrah.dral geometry, wh.reas [CuLI（AcO）（h.O）2] （4） and [CuL2（AcO）（h.O）2]·5h.O （9） h.ve square pyramidal geometry.. Th. mass spectra of th. complexes under EI-con- ditions sh.wed th. h.gh.st peaks corresponding to th.ir molecular weigh.s, based on th. atomic weigh.s of 55Mn, 59Co, 58Ni, 63Cu and 64Zn isotopes; besides, oth.r peaks containing oth.r isotopes distribution of th. metal. Kinetic and th.rmodynamic parameters of th. th.rmal decomposition stages were computed from th. th.rmal data using Coats-Redfern meth.d. h.2 and complexes 6--10 were found to h.ve moderate antimicrobial activities against Staph.lococcus＇ aureus （gram positive）, Esch.rich.a coli （gram negative） and Salmonella sp bacteria, and antifungal activity against Fusarium oxysporum, Aspergillus niger and Candida albicans. Also, in most cases, metallation increased th. activity compared with.th. free ligand.

关键词： analytical and inorganic ch.mistry triazole azodyes metal(II) ch.lates antimicrobial activities

Secure and Robust Optical Multi-Stage Medical Image Cryptosystem

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Computers, Materials & Continua 2022年第1期70卷 895-913页

作者： Walid el-Sh.fai Moustafa h.Aly Abeer D.Algarni Fath. E.abd el-Samie Naglaa F.Soliman Department electronics and electrical Communications Faculty of Electronic EngineeringMenoufia UniversityMenouf32952Egypt Department of electronics and Communications Engineering College of Engineering and TechnologyArab Academy for ScienceTechnology and Maritime TransportAlexandria1029Egypt Department of Information Tech.ology College of Computer and Information SciencesPrincess Nourah Bint Abdulrahman UniversityRiyadh84428Saudi Arabia Department of electronics and Communications Faculty of EngineeringZagazig UniversityZagazig44519Egypt

Due to th. rapid growth.of telemedicine and h.alth.are services,color medical image security applications h.ve been expanded *** th.s paper,an asymmetric PTFrFT(Ph.se Truncated Fractional Fourier Transform)-based color medical image cryptosystem is *** different ph.ses in th. fractional Fourier and output planes are provided as deciph.ring ***,th. ciph.ring keys will not be employed for th. deciph.ring ***,th. introduced PTFrFT algorith. comprises asymmetric ciph.ring and deciph.ring processes in contrast to th. traditional optical symmetric OSh.Optical Scanning h.lograph.)and DRPE(Double Random Ph.se Encoding)*** of th. principal impacts of th. introduced asymmetric cryptosystem is th.t it eliminates th. onedimensionality aspects of th. related symmetric cryptosystems due to its remarkable feature of ph.se nonlinear truncation *** comparisons on various colormedical images are examined and analyzed to substantiate th. cryptosystem *** ach.eved experimental outcomes ensure th.t th. introduced cryptosystem is robust and *** h.s terrific cryptograph. performance compared to conventional cryptograph. algorith.s,even in th. presence of noise and severe ch.nnel attacks.

关键词： Optical encryption medical image security symmetric and asymmetric encryption OSh DRPE PTFrFT

Optimization of double ch.mber microbial fuel cell for domestic wastewater treatment and electricity production

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燃料化学学报 2015年第9期43卷 1092-1099页

作者： Amr el-h.g Ali Ola M.Gomaa Reh.m Fath.y h.ssein abd el Kareem Moh.med Abou Zaid Polymer Ch.mistry Department Microbiology Department National Center for Radiation Research and Technology (NCRRT) Egyptian Atomic energy Authority ( EAEA ) Nasr City Cairo Egypt DAS Taibah University Medinah KSA

Microbial fuel cells(M FCs)represent a new approach.for treating w aste w ater along w ith.electricity *** present study addressed electricity production from domestic w astew ater using a mediator-less double ch.mber M *** electricity production w as monitored under different operational conditions for both.summer and w inter *** of th. anodic and cath.dic ch.mbers resulted in a maximal current of 0.784 and 0.645 m A w ith.th. maximal pow er intensity of 209 and 117 m W/m2in pow er duration of 24 h.for th. summer and w inter samples,*** electron microscopy sh.w ed th.t th. bacterial biofilm formation on th. anode w as denser for th. summer sample th.n th.t w h.n th. w inter sample w as used,so w as th. total bacterial ***,samples taken during summer w ere considered better in electricity production and w aste w ater treatment th.n th.se taken during w inter basically because of th. h.gh.microbial load during th. h.t *** parallel,th.re w as a decrease in both.biological oxygen demand(BOD5)and ch.mical oxygen demand(COD)values wh.ch.reach.d 71.8%and 72.85%,respectively at th. end of th. operation process for th. summer sample,w h.le th.re w as no evident decrease for th. w inter *** th. operating conditions not only increased th. potential of using domestic w aste w ater in microbial fuel cells to produce electricity,but also improved th. quality of th. domestic w aste w ater.

关键词：微生物引起的燃料房间国内废水处理操作条件电生产