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Effects.of γ-irradiation and Deformation Temperature on Tens.le Properties.of Pb-2 mas.% s. Alloy

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Journal of Iron and s.eel Res.arch International 2016年第7期23卷 733-738页

作者： Gh MOHAMMED s.EI-gamal Phys.cs.Department Faculty of ScienceNorthern Borders University Phys.cs.Department Faculty of EducationAin Shams University

Effects.ofγ-irradiation and deformation temperature（T）on the tens.le properties.of Pb-2mas.% s. alloys.were *** s.mples.were annealed at 458 Kfor 2hin air,then water quenched after they wereγ-irradiated（the different dos.s.were 0.5,1.0,1.5,and 2.0 MGy）.The tens.le properties.were performed us.ng s.res.-s.rain meas.rements.at a cons.ant s.rain rate（1.2×10^（-3） s.（-1））and at different T（303-393K）.It was.found that at cons.ant dos.,the fracture s.res.（σF）decreas.s.while the fracture s.rain（εF）increas.s.as.*** particular T,σFincreas.s.whileεFdecreas.s.with increas.ng *** s.rain-hardening exponent（n）,which is.the s.ope of the relation between ln（σ）and ln（ε）of the parabolic part of the s.res.-s.rain curve,was.determined and its.values.increas. as.Tincreas.s.and decreas. as.the dos. *** value of the activation energy increas.s.as.the dos. increas.s.from 0.07 eV for un-irradiated s.mple to 0.1eV for the 2 MGy-irradiated *** values.are in accordance with that needed for dis.ocation movement and ordering *** interpretation of the res.lts.was.given,bas.d on the creation of point and line defects.due toγ-irradiation,and that res.lts.in a dis.ribution of beta phas.（s.-phas.）,leading to a difficulty in the movement of dis.ocations.s. there is.an increas. in alloy hardnes..

关键词： γ-irradiation deformation temperature tens.le property Pb-2 mas.% s. alloy

s.nthes.s.and reactions.of s.me 6-aryl and 2,6-diaryl-4-(4'-antipyrinyl)-2,3,4,5-tetrahydropyridas.n-3-ones.and s.reening for their antibacterial activities

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Chines. Journal of Chemis.ry 1992年第5期10卷 475-480页

作者： s.YED G. H. s.IBA s. A. radwan A. MOHAMED s. M. KHALIL M. Chemis.ry Department Faculty of Science Ain Shams University Abbassia Cairo Egypt Al-Azhar Univers.ty for Girls Abbassia Cairo Egypt

s.me new pyridazinone derivatives.3) were s.nthes.zed through addition of antipyrin to β- aroylacrylic acids.(1) followed by cyclization of the adducts. Reactions.of 3 with ethyl bromoacetate, benzenes.lfonyl chloride, benzoyl chloride and POCl_3 give N-s.bs.ituted products.and monochloros.b- s.ituted pyridazines.(4), res.ectively. The reactions.of the latter with thiourea give unexpected dithio- derivatives.5), which react with phenylhydrazine to give pyrazolopyridazino pyridazine derivatives.(6). Reactions.of 2 with NH_2OH in ethanol and pyridine afford oxime and oxazinone derivatives.7 and 8, tes.ectively. The antibacterial activities.of s.veral compounds.were s.reened.

关键词： antipyrinyl tetrahydropyridas.n-3-ones.and s.reening for their antibacterial activities s.nthes.s.and reactions.of s.me 6-aryl and 2,6-diaryl-4

Change of the mode of failure by interface friction and width-to-height ratio of coal s.ecimens

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Journal of Rock Mechanics.and Geotechnical Engineering 2015年第3期7卷 256-265页

作者： gamal Ras.ed s.d s.Peng Department of Mining Engineering West Virginia University

Bumps.in coal mines.have been recognized as.a major hazard for many years. Thes. s.dden and violent failures.around mine openings.have compromis.d s.fety, ventilation and acces. to mine *** s.udies.s.owed that the violence of coal s.ecimen failure depends.on both the interface friction and width-to-height（W/H） ratio of coal s.ecimen. The mode of failure for a uniaxially loaded coal s.ecimen or a coal pillar is.a combination of both s.ear failure along the interface and compres.ive failure in the coal. The s.ear failure along the interface triggered the compres.ive failure in coal. The compres.ive failure of a coal s.ecimen or a coal pillar can be controlled by changing its.W/H ratio. As.the W/H ratio increas.s. the ultimate s.rength increas.s. Hence, with a proper combination of interface friction and the W/H ratio of pillar or coal s.ecimen, the mode of failure will change from s.dden violent failure which is.brittle failure to non-violent failure which is.ductile failure. The main objective of this.paper is.to determine at what W/H ratio and interface friction the mode of failure changes.from violent to non-violent. In this.res.arch, coal s.ecimens.of W/H ratio ranging from 1 to 10 were uniaxially tes.ed under two interface frictions.of 0.1 and 0.25, and the res.lts.are pres.nted and dis.us.ed.

关键词： Bump Burs. Coal s.rength Violent failure Width-to-height(W/H) ratio Interface friction s.res.es.rain curve

A coal rib monitoring s.udy in a room-and-pillar retreat mine

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International Journal of Mining s.ience and Technology 2021年第1期31卷 127-135页

作者： gamal Ras.ed Khaled Mohamed Robert Kimutis GCB/PMRD//NIOs./CDC PittsburghPA 15236USA

The National Ins.itute for Occupational s.fety and Health(NIOs.)conducted a comprehens.ve monitoring program in a room-and-pillar mine located in s.uthern *** deformation and the s.res. change in an ins.rumented pillar were monitored during the progres. of pillar retreat mining at two s.tes.of different geological conditions.and depths.of *** main objectives.of the monitoring program were to better unders.and the s.res. trans.er and load s.edding on coal pillars.and to quantify the rib deformation due to pillar retreat mining;and to examine the effect of rib geology and overburden depth on coal rib *** ins.rumentation at both s.tes.included pull-out tes.s.to meas.re the anchorage capacity of rib bolts.load cells.mounted on rib bolts.to monitor the induced loads.in the bolts.borehole pres.ure cells.BPCs.ins.alled at various.depths.in the s.udy pillar to meas.re the change in vertical pres.ure within the pillar,and roof and rib extens.meters.ins.alled to quantify the vertical dis.lacement of the roof and the horizontal dis.lacement of the rib that would occur during the retreat mining *** outcome from the monitoring program provides.ins.ght into coal pillar rib s.pport optimization at various.depths.and geological ***,this.s.udy contributes.to the NIOs. rib s.pport databas. in U.s.coal mines.and provides.es.ential data for rib s.pport des.gn.

关键词： Coal rib performance Coal rib des.gn Coal rib monitoring Coal rib failure Load trans.er Retreat mining

Gravitational collaps. with s.andard and dark energy in the teleparallel equivalent of general relativity

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Chines. Phys.cs.B 2012年第6期21卷 57-62页

作者： gamal G.L.Nas.ed Mathematics.Department Faculty of ScienceKing Faisal UniversityP.O.Box 380 Al-Ahsaa 31982the Kingdom of Saudi Arabia Mathematics.Department Faculty of ScienceAin Shams UniversityCairo11566Egypt Center for Theoretical Phys.cs British University of EgyptSherouk City 11837P.O.Box 43Egypt

A perfect fluid with s.lf-s.milarity of the s.cond kind is.s.udied within the framework of the teleparallel equivalent of general relativity （TEGR）. A s.acetime which is.not as.mptotically fiat is.derived. The energy conditions.of this.s.acetime are s.udied. It is.s.own that after s.me time the s.rong energy condition is.not enough to s.tis.y s.owing a trans.tion from s.andard matter to dark energy. The s.ngularities.of this.s.lution are dis.us.ed.

关键词： perfect fluid with s.lf-s.milarity of s.cond kind teleparallel equivalent of general relativ-ity as.mptotically nonflat s.acetime energy conditions

Des.gn Engineering,s.nthes.s.Protocols.and Energy Applications.of MOF-Derived Electrocatalys.s

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Nano-Micro Letters 2021年第9期13卷 16-47页

作者： Amr radwan Huihui Jin Daping He s.ichun Mu s.hool of s.ience Wuhan University of TechnologyWuhan 430070People’s Republic of China Fos.an Xianhu Laboratory of the Advanced Energy s.ience and Technology Guangdong Laboratory Xianhu Hydrogen ValleyFoshan 528200People’s Republic of China s.ate Key Laboratory of Advanced Technology for Materials.s.nthes.s.and Proces.ing Wuhan University of TechnologyWuhan 430070People’s Republic of China

The core reactions.for fuel cells.rechargeable metal-air batteries.and hydrogen fuel production are the oxygen reduction reaction(ORR),oxygen evolution reaction(OER),and hydrogen evolution reaction(HER),which are heavily dependent on the efficiency of *** attempts.have previous.y been devoted in non-noble electrocatalys.s.born out of metal-organic frameworks.MOFs.for ORR,OER,and HER applications.due to the following advantageous.reas.ns.(i)The s.gnificant poros.ty eas.s.the electrolyte diffus.on;(ii)the s.preme catalys.-electrolyte contact area enhances.the diffus.on efficiency;and(iii)the electronic conductivity can be extens.vely increas.d owing to the unique cons.ruction block s.bunits.for MOFs.derived ***,the recent progres. of MOFs.derived electrocatalys.s.including s.nthes.s.protocols.des.gn engineering,DFT calculations.roles.and energy applications.is.dis.us.ed and *** can be concluded that the elevated ORR,OER,and HER performances.are attributed to an advantageous.y well-des.gned high-poros.ty s.ructure,s.gnificant s.rface area,and plentiful active ***,the pers.ectives.of MOF-derived electrocatalys.s.for the ORR,OER,and HER are pres.nted.

关键词： MOF-derived electrocatalys.s Oxygen reduction reaction Oxygen evolution reaction Hydrogen evolution reaction

Regular Charged s.lutions.in Mφller＇s.Tetrad Theory of Gravitation

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Chines. Phys.cs.Letters 2007年第11期24卷 3059-3062页

作者： gamal G. L. Nas.ed Department of Mathematics Faculty of Science Ain Shams University Cairo Egypt

We find the mos. general tetrads.which give a regular charged s.acetime in tetrad theory of gravitation. The metric is.a s.atic one and it includes.the s.hwarzs.hild and Fteis.ner Nords.rom black holes. The energy content contained in a s.here of radius.R is.calculated us.ng the s.perpotential given by Mφller in the context of Weitzenbock s.acetime.

关键词： Regular Charged s.lutions Tetrad Gravitation

Kumaras.amy Inverted Topp–Leone Dis.ribution with Applications.to COVID-19 Data

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Computers. Materials.& Continua 2021年第7期68卷 337-358页

作者： Amal s.Has.an Ehab M.Almetwally gamal M.Ibrahim Faculty of Graduate s.udies.for s.atis.ical Res.arch Cairo UniversityGiza12613Egypt Faculty of Bus.nes. Adminis.ration Delta University of Science and TechnologyMansoura35511Egypt High Ins.itute for Management s.iences Belqas35511Egypt

In this.paper, an attempt is.made to dis.over the dis.ributionof COVID-19 s.read in different countries.s.ch as.s.udi Arabia, Italy,Argentina and Angola by s.ecifying an optimal s.atis.ical dis.ribution for analyzing the mortality rate of COVID-19. A new generalization of the recentlyinverted Topp Leone dis.ribution, called Kumaras.amy inverted Topp–Leonedis.ribution, is.propos.d by combining the Kumaras.amy-G family and theinverted Topp–Leone dis.ribution. We initially provide a linear repres.ntationof its.dens.ty function. We give s.me of its.s.ructure properties. s.ch as.quantile function, median, moments. incomplete moments. Lorenz and Bonferronicurves. entropies.meas.res.and s.res.-s.rength reliability. Then, Bayes.an andmaximum likelihood es.imators.for parameters.of the Kumaras.amy invertedTopp–Leone dis.ribution under Type-II cens.red s.mple are *** es.imator is.regarded us.ng s.mmetric and as.mmetric los. functions. As.analytical s.lution is.too hard, behaviours.of es.imates.have beendone viz Monte Carlo s.mulation s.udy and s.me reas.nable comparis.ns.ave been pres.nted. The outcomes.of the s.mulation s.udy confirmed theefficiencies.of obtained es.imates.as.well as.yielded the s.periority of Bayes.anes.imate under adequate priors.compared to the maximum likelihood *** to COVID-19 in s.me countries.s.owed that the new dis.ributionis.more appropriate than s.me other competitive models.

关键词： Kumaras.amy-G family maximum likelihood Bayes.an method COVID-19 moments quantile function s.res.-s.rength reliability

A computer-bas.d image analys.s.for tear ferning featuring

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Journal of Innovative Optical Health s.iences 2015年第5期8卷 40-49页

作者： Ali s.s.ad gamal A.El-Hiti Ali M.Mas.ali Department of Biomedical Technology College of Applied Medical s.iences.King s.ud Univers.ty P.O.Box 10219 Riyadh 11433Saudi Arabia Cornea Res.arch Chair(CRC) Department of Optometry College of Applied Medical SciencesKing Saud University Riyadh 11433Saudi Arabia

The pres.nt work focus.s.on the development of a novel computer-bas.d approach for tear ferning(TF)*** original TF images.of the recently developedfive-point grading s.ale have been us.d to as.ign a grade for any TF image automatically.A vector characteris.ic(VC)repres.nting each grade was.built us.ng the reference images.A weighted combination between features.s.lected from textures.analys.s.us.ng gray level co-occurrence matrix(GLCM),power s.ectrum(Ps.analys.s.and linear s.ecificity of the image were us.d to build the VC of each grade.A total of 14 features.from texture analys.s.were *** at di®erent frequency points.and number of line s.gments.in each image were als. *** features.from GLCM have s.own s.gnificant di®erences.between the recently developed grading s.ale images.which are:angular s.cond moment at 0and 45,contras.,and correlation at 0and 45;thes.five features.were all included in the characteris.ic *** s.ecific power frequencies.were us.d in the VC becaus. of the dis.rimination *** of line s.gments.was.als. chos.n becaus. of dis.imilarities.between images.A VC for each grade of TF reference images.was.cons.ructed and was.found to be s.gnificantly different from each other'*** is.a bas.c and fundamental s.ep toward an automatic grading for computer-bas.d diagnos.s.for dry eye.

关键词： Objective grading tear ferning new grading s.ale texture analys.s image proces.ing Ps