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PVC nanocomposites f.r cable insulation with enhanced dielectric properties,partial discharge resistance and mechanical perf.rmance

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High Voltage 2020年第4期5卷 463-471页

作者： Nagat M.K.Abdel-Gawad Adel z.el Dein Diaa-eldin A.Mansour Hanaa M.Ahmed Mohamed M.f.Darwish Matti Lehtonen Department of.electrical Power and Machines Engineering Faculty of Engineering at ShoubraBenha UniversityCairoEgypt Department of.High Voltage Networks Faculty of Energy EngineeringAswan UniversityAswanEgypt High Voltage and Superconductivity Laboratory Department of Electrical Power and Machines EngineeringFaculty of EngineeringTanta UniversityTantaEgypt Department of.Mathematics and Engineering Physics Faculty of Engineering at ShoubraBenha UniversityCairoEgypt Department of.electrical Engineering and Automation School of Electrical EngineeringAalto UniversityEspooFinland

The current study aims to develop polyvinyl chloride(PVC)nanocomposites with enhanced electrical and mechanical properties by incorporating titanium oxide(TiO_(2))nanoparticles within PVC *** loading of.nanoparticles and dif.erent nanoparticle surf.ce states were *** surf.ce states are unf.nctionalised,f.nctionalised using vinyl silane and f.nctionalised using amino *** choice of.a most suitable surf.ce state was a critical f.ctor that guarantees a good dispersion of.nanoparticles and consequently enhances the compatibility between TiO_(2)and PVC *** process f.llowed in the PVC/TiO_(2)nanocomposites preparation,loaded with dif.erent wt.%of.TiO_(2)nanoparticles,was the solvent *** dielectric properties measured here were the relative permittivity(ɛr),dielectric loss(tanδ),breakdown strength(AC and DC under unif.rm f.eld)and the internal partial discharges(PDs)within insulation *** measurements have been perf.rmed under room temperature and at f.equency ranged f.om 20 to 1.0 ***,the mechanical properties of.the samples like elongation,elasticity modulus and tensile strength were also *** silane showed better improvements in both electrical and mechanical perf.rmances compared to the amino silane,especially in cases of.high weight f.actions of.TiO_(2).This is because of.the improvement in the PVC-TiO_(2)interf.cial region arise f.om the similarity of.polarity and surf.ce tension values of.vinyl silane with that of.PVC matrix and TiO_(2)nanoparticles.

关键词： dielectric insulation resistance

Impact of.National Egyptian school f.eding program on growth,development,and school achievement of.school children

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World Journal of.Pediatrics 2020年第4期16卷 393-400页

作者： A.M.Metwally Marwa M.el-Sonbaty L.A.el Etreby E.M.Salah el-Din N.Abdel Hamid H.A.Hussien A.M.Hassanin z.M.Monir Medical Research Division Community Medicine DepartmentNational Research Centre(Affiliation ID:60014618)DokkiCairoEgypt Department of.Pediatrics College of MedicineTaibah UniversityMadinahKingdom of Saudi Arabia Medical Research Division Child Health DepartmentNational Research Centre(Affiliation ID:60014618)DokkiCairoEgypt Agricultural Research Centre GizaEgypt

Background School f.eding program(Sf.)increases access to education and to better *** study aims to evaluate the ef.ects of.Sf. on physical growth,cognitive development,psychosocial behavior,and learning achievement of.school *** A quasi-experimental study was *** intervention group included 903 pupils in the f.f.h grade receiving the school meal,while the control group included 886 pupils,matched f.r age and sex,without *** meal consisted of.a pie made of.f.our f.rtif.ed with vitamins A,B6,B12,C,thiamin,ribof.avin,niacin,f.late,calcium,iron,z.nc,and *** position,nutritional status,and dietary behavior were *** tests were *** behavior was rated and educational achievement was *** hoc and independent sample t tests were used to detect the association of.the studied parameters with the intake of.school *** Children who took the meal had better scores on visual memory,auditory vigilance tests(9.71±2.80 vs.7.45±3.25;25.02±3.36 vs.10.82±8.92,respectively,Pf.ernoon attention and working memory test(8.20±2.21vs.7.75±3.05)(Pf.externaliz.ng behavior(Pf.cant changes of.children’s nutritional status were detected between the two *** meal was the main predictor of.visual memory and auditory vigilance(Pf.academic achievements when combined with f.mily siz. and meals’f.equency(Pf.school children.

关键词： Cognition Growth Perf.rmance School f.eding

Sof. X-Ray Laser Gain f.om Neon like Gallium and Germanium

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Journal of.Modern Physics 2016年第9期7卷 928-935页

作者： Mohammad z. Mansour Wessameldin S. Abdelaz.z.Tharwat M. el Sherbini National Institute of.Laser Enhanced Sciences Cairo University Giza Egypt Laboratory of.Lasers and New Materials Faculty of Science Cairo University Giza Egypt

Gain coef.icients are calculated f.r neon-like gallium and germanium ions. Shorter wavelengths are calculated and predicted to be emitted. The gain coef.icients are calculated among 457 energy levels of.the neon-like ions. Collisional excitations were calculated through the distorted wave approximations through f.ve electron temperatures Te = 300, 500, 700, 1000 and 1500 eV.

关键词： Gain Coef.icients X-Ray Lasers Collisional Radiative Model

Evolutions　of.f.ow　f.eld　and　heat　exchange　on　equa-torial　Pacif.c　surf.ce　in　el　Nino-La　Nina　cycle

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Acta Oceanologica Sinica 1997年第2期16卷 157-170页

作者： Ma K. Yao H. Lin z. Chao J. Department of.Atmospheric Sciences Nanjing University Nanjing 210093 China Climate Center of.China Beijing 100081 China

Ｉｎｔｈｉｓｐａｐｅｒ，ｔｈｅｍｏｎｔｈｌｙａｖｅｒａｇｅｓａｎｄｄｅｖｉａｔｉｏｎｓｏｆｔｅｍｐｅｒａｔｕｒｅ，ｐｒｅｓｓｕｒｅ，ｚｏｎａｌｗｉｎｄ，ｓｐｅｃｉｆｉｃｈｕｍｉｄｉｔｙ，ｃｌｏｕｄｃｏｖｅｒａｎｄｔｈ... 详细信息

Ｉｎｔｈｉｓｐａｐｅｒ，ｔｈｅｍｏｎｔｈｌｙａｖｅｒａｇｅｓａｎｄｄｅｖｉａｔｉｏｎｓｏｆｔｅｍｐｅｒａｔｕｒｅ，ｐｒｅｓｓｕｒｅ，ｚｏｎａｌｗｉｎｄ，ｓｐｅｃｉｆｉｃｈｕｍｉｄｉｔｙ，ｃｌｏｕｄｃｏｖｅｒａｎｄｔｈｅｃｏｍｐｏｎｅｎｔｓｏｆｈｅａｔｂｕｄｇｅｔｈａｖｅｂｅｅｎｍｐｕｔｅｄｏｎｔｈｅｅｑｕａｔｏｒｉａｌ（５．Ｓ－３．Ｎ）Ｐａｃｉｆｉｃｓｕｒｆａｃｅ（ＥＰＳ）ｂａｓｅｄｏｎｔｈｅ２．ｘ２．ｇｒｉｄｄａｔａｏｆＣＯＡＤＳｆｒｏｍ１９５０ｔｏ１９８７ａｎｄｔｈｅｅｖｏｌｕｔｉｏｎｓｏｆｔｈｅｓｅｅｌｅｍｅｎｔｓｈａｔｅｂｅｅｎｐｒｏｖｉｄｅｄ．ＴｗｏｆｅｅｄｂａｃｋｍｅｃｈａｎｉｓｍｓｏｆＥｌＮｉｎｏ－ＬａＮｉｎａｃｙｃｌｅｗｈｉｃｈｉｎｃｌｕｄｅｔｈｅｄｙｎａｍｉｃ，ｔｈｅｒｔｔａｌａｎｄｈｙｄｒｏｌｏｇｉｃｔｌｐｒｏｃｅｓｓｅｓｉｎｔｈｅｏｏｕｐｌｅｄａｉｒｔｓｅａｓｙｓｔｅｍａｒｅｖｅｒｉｆｉｅｄ．ＤｕｒｉｎｇＥ１Ｎｉｎｏ．ｔｈｅｐｒｅｓｓｕｒｅｇｒａｄｉｅｎｔａｎｄｔｒａｄｅｗｉｎｄｄｅｃｒｅａｓｅｄｏｎｔｈｅＥＰＳ，ｔｈｅｓｅｎｓｉｂｌｅａｎｄｌａｔｅｎｔｈｅａｔｅｘｃｈａｎｇｅｓｅｎｌ

关键词： Nino-La Nina cycle surf.ce Pacif.c el Evolutions La heat f.ow

Stem taper equations f.r diameter and volume predictions of.Abies cilicica *** the Taurus Mountains,Turkey

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Journal of.Mountain Science 2020年第12期17卷 3054-3069页

作者： Onur ALKAN Ramaz.n Oz.elIK f.culty of.f.restry Isparta University of Applied SciencesEast Campus32260IspartaTurkey

Taper equations are an important tool in estimating stem volumes at a multi-product level f.r sustainable f.rest *** taper equations are tested f.om three categories to estimate diameter at specif.ed point on the stem,height at specif.ed diameter,volumes of.any desired portion of.the stem,and whole tree volume of.Taurus f.r in Taurus Mountains of.*** account f.r autocorrelation and multicollinearity present among multiple stem data observations collected f.om the same *** statistical approaches were used in model *** are made to determine which equation provides the best overall f.t to all data based on f.ur goodness-of.f.t statistics,Coef.icient of.determination(R2);Root mean square error(RMSE),Akaike’s Inf.rmation Criterion(AIC),and Bayesian inf.rmation criterion(BIC).Results indicated that all taper equations tested could be used to accurately estimate section diameter at given height and stem *** et al.’s taper equation provided better results than the others f.r Taurus f.r when an additional stem diameter observation at 5.30 m was *** and variable-f.rm taper models consistently provided better results than the simple taper models except f.r Max and Burkhart’s *** et al.’s and Koz.k’s taper models showed equally good perf.rmance to describe stem taper and to predict tree stem ***,these taper equations are able to be used to estimate diameter and volume f.r Taurus f.r trees,if.an upper stem diameter measurement was not available.

关键词： Autocorrelation Ranking system Stem f.rm Segmented models Variable-f.rm models

Medicinal and biological values of.Callistemon viminalis extracts:History,current situation and prospects

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Asian Pacif.c Journal of.Tropical Medicine 2017年第3期10卷 219-226页

作者： Mohamed z.M.Salem Mervat el-Hef.y Ramadan A.Nasser Hayssam M.Ali Nader A.el-Shanhorey Hosam O.elansary f.restry and Wood Technology Department Faculty of Agriculture(El-Shatby)Alexandria UniversityAlexandriaEgypt Department of.f.oriculture Ornamental Horticulture and Garden DesignFaculty of Agriculture(EL-Shatby)Alexandria UniversityAlexandriaEgypt Department of.Botanical Gardens Research Horticultural Research Institute(ARC)AlexandriaEgypt King Saud University College of ScienceDepartment of Botany and MicrobiologyPO Box 2455Riyadh 11451Saudi Arabia Agriculture Research Center Horticulture Research InstituteSabahia Horticulture Research StationDepartment of Timber Trees ResearchAlexandriaEgypt

Callistemon viminalis(***)is a plant that has been reported to have a various medicinal values such as antibacterial,antif.ngal,antioxidant activities and other pharmaceutical and insecticidal *** review covers the potentials,applications and properties of.dif.erent extracts f.om dif.erent parts(branches,f.owers,f.uits,bark,leaves)of.***,the chemical structures of.the bioactive compounds were reported f.r biological *** the results supported the traditional uses of.*** in f.lk *** addition,some researches supported the use of.*** extracts f.r the preparation of.metal oxide nanoparticles.

关键词： Callistemon viminalis Antibacterial activity Antioxidant activity Antif.ngal activity Essential oils Biological activities

Scanning electron Microscopically Study of.Sesame Seeds Inf.cted with Macrophomina phaseolina

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Journal of.Agricultural Science and Technology(A) 2011年第1X期1卷 96-99页

作者： D. A. el-Wakil A. M. Mahdy R. z. el-Menshawy Plant Pathology Research Institute ARC Post No. 12619 Giza Egypt Department of.Agricultural Botany Faculty of Agriculture Moshtohor Benha University Cairo Egypt f.culty of.Science and Humanities Studies AI-Kharj University Kingdom of Saudi Arabia

The direct impact of.seed-borne f.ngi on seed is considerable. Many f.ngi are serious parasites of.seed primordial and maturing seeds and reduce yield of.seed both quantitatively and qualitatively. Other f.ngi, including saprophytes and very weak parasites, may lower the quality of.seeds by causing discoloration which may seriously depreciate the commercial value of.seeds, particularly of.grain when graded f.r consumption. Studies by using scanning electron microscopy （SEM） conf.rmed the importance of.the seed coat, and seed cells as inf.ction sites as well as location of.the mycelium of.the investigated f.ngus. Macrophominaphaseolina The present investigation is undertaken to study the coloniz.tion, inf.ction and f.ngal establishment on dif.erent sesame seed parts by （SEM）. A successf.l coloniz.tion of.M. phaseolina to seed tissues was also detected. Dif.erent f.rms of.pycnidial shapes were also observed.

关键词： Scanning electron microscope Macrophomina phaseolina sesame seed

Nz.合金在不同介质中腐蚀后氧化膜的晶体结构

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材料研究学报 2008年第3期22卷 327-332页

作者：章海霞李中奎张建军郑欣 f.UCHART Daniel HLIL el kebir 孙军周廉西安交通大学材料科学与工程学院西安710049 西北有色金属研究院西安710016 Institut Neel CNRS BP 16638042 GrenobleCedex 9France

通过分析Nz.合金在360℃、18.6 MPa含锂水和400℃、10.3 MPa蒸汽中腐蚀后氧化膜的晶体结构,研究了腐蚀过程中氧化膜晶体结构的转变及其对锆合金耐腐蚀性能的影响.结果表明:Nz.合金腐蚀后氧化膜的结构以单斜氧化锆为主,还有一定量畸变了... 详细信息

通过分析Nz.合金在360℃、18.6 MPa含锂水和400℃、10.3 MPa蒸汽中腐蚀后氧化膜的晶体结构,研究了腐蚀过程中氧化膜晶体结构的转变及其对锆合金耐腐蚀性能的影响.结果表明:Nz.合金腐蚀后氧化膜的结构以单斜氧化锆为主,还有一定量畸变了的四方氧化锫.四方氧化锆主要由氧化膜内的压应力稳定.随着腐蚀时间的延长,氧化膜与金属间的界面向前推进,当氧化锆中的压应力不足以稳定四方相时,四方氧化锆转变为单斜氧化锆.从氧化膜与金属间的界面到氧化膜的外表面,四方相的含量不断降低,界面处的四方相含量最高.Nz.合金在360℃含锂水中腐蚀时,氧化膜内四方相向单斜相的转变速度比在400℃蒸汽中腐蚀时四方相向单斜相的转变速度低得多.四方相向单斜相的转变是决定锆合金抗腐蚀性能的主要因素,四方相转变得越快,其含量越低,腐蚀速率越高.

关键词：材料失效与保护氧化膜晶体结构腐蚀性能 Raman光谱

Bound in continuum states and induced transparency in mesoscopic demultiplexer with two outputs

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Chinese Physics B 2020年第12期29卷 429-437页

作者： z.Labdouti T Mrabti A Mouadili E H el Boudouti f.f.thi B Djaf.ri-Rouhani LPMR Dèpartement de PhysiqueFacultèdes SciencesUniversitèMohammed IOujdaMorocco LSTA Dèpartement de PhysiqueFacultèPolydisciplinaire de LaracheUniversitèAbdelmalek EssaadiTètouanMorocco LPMCER Dèpartement de PhysiqueFacultèdes Sciences et Techniques de MohammediaUniversitèHassan IICasablancaMorocco IEMN UMR CNRS 8520UFR de PhysiqueUniversitède Lille59655 Villeneuve d'AscqFrance

We investigate the electronic transport in a simple mesoscopic cross structure made of.two wires(stubs)graf.ed at the same point along a quantum *** show that the structure may exhibit important phenomena such as bound in continuum(BIC)*** states are transf.rmed into electromagnetically induced transparency(EIT)resonance by detuning slightly the lengths of.the *** last phenomenon is used to propose and study a mesoscopic demultiplexer device with an input waveguide and two output *** give closed-f.rm expressions of.the geometrical parameters that allow a selective transf.r of.a given state in the f.rst waveguide without perturbing the second *** ef.ect of.temperature on the transmission resonances is also examined by using Landauer-Büttiker *** analytical results of.the dispersion relation and transmission and ref.ection coef.icient are obtained using the Green's f.nction method.

关键词： mesoscopic structure demultiplexer device bound states in continuum(BIC) EIT resonance