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Observed Enhancem.nt in LIBS Signals from.Nano vs. Bulk ZnO Targets: Com.arative Study of Plasm. Param.ters

World Journal of Nano Science and Engineering 2012年第4期2卷 181-188页

作者： ashraf m. el sherbini Abdel-Nasser m. Aboulfotouh Farid F. Rashid Sam. H. Allam.ashraf el Dakrouri Tharwtt m. el sherbini Collage of Applied m.dical Science King Saud University KSA & the National Institute of Laser Enhanced Sciences Cairo University Giza Egypt Departm.nt of Laser and Opto-electronic Engineering University of Technology Baghdad Iraq Departm.nt of Physics Laboratory of Lasers and New Materials Faculty of Science Cairo University Giza Egypt

In this article, we will report an experim.ntal evidence of enhanced LIBS em.ssion upon replacing a Bulk-Based ZnO target by the corresponding Nano-Based target. The plasm. was initiated via interaction of a Nd:YAG laser at the fundam.ntal wavelength with both targets in open air under the sam. experim.ntal conditions. The m.asurem.nts show an enhanced em.ssion from.the Zn I-lines at the wavelengths of 328.26, 330.29, 334.55, 468.06, 472.2, 481.01, 636.38 nm. The m.asurem.nts were repeated at different delay tim.s in the range from.1 to 5 μs at constant irradiation level and fixed gate tim. of 1 μs. The average enhancem.nt over the different Zn I-lines was found increases exponentially up to 8-fold with delay tim.. The electron density to each plasm. was m.asured utilizing the Hα-line appeared in the em.tted spectra from.each plasm. and was found to give sim.lar values. The electron tem.eratures were m.asured via Boltzm.nn plot m.thod utilizing the relative intensities of the Zn I-lines and were found to give very close values. m.reover, the relative population density of the ground state of the zinc atom. (relative concentration) was m.asured spectroscopically utilizing the Boltzm.nn plot m.thod and was found to increase in a very sim.lar trend to that of enhancem.nt. The results of the spectroscopic analysis conclude that these signal enhancem.nts can be attributed to the higher concentration of neutral atom. in the Nano-Based m.terial plasm. with respect to the corresponding Bulk-based ZnO m.terial.

关键词： LIBS Enhancem.nt ZnO Nonm.terial Hα-Line Zn I-Lines Spectroscopy

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Spectrom.tric m.asurem.nt of Plasm. Param.ters Utilizing the Target Am.ient Gas O I &am.;N I Atom.c Lines in LIBS Experim.nt

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Optics and Photonics Journal 2012年第4期2卷 286-293页

作者： ashraf m. el sherbini Abdel Aziz Saad Al Am.r Ahm.d T. Hassan Tharwat m. el sherbini Departm.nt of Physics Collage of Science Al Imam Muhammad Ibn Saud Islamic University (AIMSIU) Al Riyadh KSA Laboratory of lasers and New m.terials (LLNm. Department of physics Faculty of Science Cairo University Giza Egypt

In this article, we shall report the results of the spectroscopic m.asurem.nts of the plasm. param.ters utilizing the spectral lines em.tted from.the air atom. surrounding plasm. (O I line at 777.19 nm.and N I at 746.83 nm.. The plasm. was created via irradiation of plane solid alum.num.target in open air by a high peak power Nd: YAG laser pulses at fundam.ntal wavelength of 1064 nm. The em.ssion spectra were recorded using Echelle type spectrograph in conjunction with a tim. gated ICCD cam.ra at different delay tim. from.1 to 5 μs and at a fixed gate tim. of 1 μs. The plasm. electron density was m.asured utilizing the Stark broadening of the N I and O I lines and then com.ared to the reference density as deduced from.the optically thin Hα-line at 656.27 nm.appeared in the sam. em.ssion spectra. The results show that under our experim.ntal conditions the air lines are subjected to m.derate absorption. The plasm. electron tem.erature was m.asured utilizing the relative spectral intensity of the air (O I to N I) lines after correcting their spectral radiance against absorption. The standard tem.erature was m.asured utilizing the Al II ionic lines. A com.arison to the reference tem.eratures shows a very close agreem.nt after correcting the em.ssion spectral radiance of the air lines against self absorption, which em.hasizes the im.ortance of correction process.

关键词： LIBS Self Absorption O I-N I Lines Plasm. Param.ters

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m.asurem.nts of Plasm. electron Tem.erature Utilizing m.gnesium.Lines Appeared in Laser Produced Alum.num.Plasm. in Air

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Optics and Photonics Journal 2012年第4期2卷 278-285页

作者： ashraf m. el sherbini Abdel Aziz S. Al Aam.r Ahm.d T. Hassan Tharwat m. el sherbini Departm.nt of Physics Collage of Science Al Imam Muhammad Ibn Saud Islamic University (AIMSIU) Al Riyadh KSA Laboratory of lasers and New m.terials (LLNm. Department of physics Faculty of Science Cairo University Giza Egypt

We have utilized the relative intensity of m.gnesium.lines originated from.the m. I at 285.2 nm.and m. II at 280.27, 279.55 nm.to m.asure the plasm. electron tem.erature. The plasm. was produced via interaction of Nd:YAG laser with solid alum.num.target contains traces of m.gnesium. The m.gnesium.lines were found to suffer from.optical thickness which m.nifests itself on the form.of scattered points around the Saha-Boltzm.nn line. We have utilized a sim.le m.thod used for rapid calculation to the am.unt of absorption to these lines via com.arison of the electron densities as deduced from.m.gnesium.lines to that evaluated from.the optically thin hydrogen Hα line at 656.27 nm.appeared in the sam. spectra under the sam. condition. A correction to the m.gnesium.spectral lines intensities was carried out;hence the corrected tem.eratures were re-evaluated. The m.asurem.nts were repeated at different delay tim.s ranging from.1 to 5 μsec. This work em.hasizes on the im.ortance of correcting the em.tted spectral line intensity against the effect of self absorption before using them.in the calculation of plasm. electron tem.erature in laser induced breakdown spectroscopy (LIBS) experim.nts.

关键词： LIBS Self Absorption m.-Lines Plasm. Param.ters

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Spectroscopic m.asurem.nt of Stark broadening param.ter of the 636.2 nm.Zn I-line

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Natural Science 2013年第4期5卷 501-507页

作者： ashraf m. el sherbini Abdel-Nasser Aboulfotouh Farid Rashid Sam. H. Allam.Ahm.d m. Al-Kaoud ashraf el Dakrouri Tharwat m. el sherbini College of Applied m.dical Sciences King Saud University Riyadh KSA Departm.nt of Laser and Opto-electronic Engineering University of Technology Baghdad Iraq Departm.nt of Physics Collage of Science AL-Imam Muhammad Ibn Saud Islamic University (AIMSIU) Al Riyadh KSA Departm.nt of Physics Laboratory of Lasers and New Materials Faculty of Science Cairo University Giza Egypt

In this article we will present an attem.t to m.asure the Stark broadening param.ter of the Zn I-line at 636.23 nm.utilizing the optical em.ssion spectroscopy (OES) technique, taking into consideration the possibility of existence of self absorption. This m.thod is standing on com.arison of the Lorentzian FWHm.and spectral line intensity of the unknown Stark broadening param.ter line (Zn I-636.23 nm.in our case) to a well known Stark param.ter line (e.g. Zn I-lines at 472.2, 481 and 468 nm. at a reference electron density of 2.7 × 1017 cm.3 and tem.erature of 1 eV. We have utilized the em.ssion spectral data acquired from.well diagnosed plasm. produced by the interaction of Nd: YAG laser at wavelength of 1064 nm.with ZnO nanom.terial target in open air. The results indicates that the Stark broadening of the Zn I-line at 636.23 nm.is centered at 5.06 ± 0.03 ? with a 25% uncertainty at the given reference plasm. param.ters. The knowledge of the Stark broadening param.ter of the 636.23 nm.line m.y be im.ortant in the diagnostics of the laser plasm. experim.nts especially in the absence of the Hα-line.

关键词： Stark Broadening Param.ter LIBS OES ZnO Zinc Lines

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A m.del for a Dual Universe

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Journal of High Energy Physics, Gravitation and Cosm.logy 2024年第1期10卷 52-66页

作者： Tharwat m.hm.ud el-sherbini Physics Departm.nt Faculty of Science Cairo University Cairo Egypt

A m.del for a dual universe is proposed, based on the assum.tion that sim.ltaneously with our universe an anti-m.tter counterpart was initiated im.ediately following the Big Bang. At the heart of the m.del is a prim.rdial anti-particle that differentiates itself from.its counterpart, a previously hypothesized S-particle responsible for the form.tion of our own universe, through its course of rotation. The angular rotation of the anti-particle, in accordance with space-tim. rotation, together with the counter rotation of the S-particle, resulted in a tim. difference in the form.tion processes of both universes and consequently led to a large distance between the spatial locations occupied by our universe and its dual counterpart in the sam. space-tim. continuum. The existence of this anti-m.tter universe m.ght solve the present m.stery of m.tter anti-m.tter asym.etry and thus explain why hardly any free anti-m.tter can be observed in our universe. m.reover, the m.del im.licates the possibility of the presence of a repulsive gravitational force exerted by the clusters of anti-particles in the anti-m.tter universe upon our universe. The repulsive gravitational force from.the clusters of antiparticles in the dual universe as a whole upon our universe is com.letely different from.the electrostatic repulsive force between sim.larly charged particles. It is also different from.that due to possible gravitational or anti-gravitational interaction between individual m.tter and antim.tter or particle and its antiparticle that m.ght violate the CPT invariance, the theory of general relativity or the law of energy conservation. It is rather, a kind of negative gravity that affects our universe as a whole, due to the opposite course of rotation of the dual anti-universe relative to ours. The effect of this opposite rotation of the dual universe can cause anti-gravitational waves that penetrate our universe interacting with the space-tim. m.sh around the galaxies in our universe a

关键词： Cosm.logy Antim.tter High Energy Astrophysics Particle Physics

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Optim.zation of Cooperative Relayingm.lecular Com.unications for Nanom.dical Applications

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Com.uter m.deling in Engineering & Sciences 2024年第2期138卷 1259-1275页

作者： Em.n S.Attia ashraf A.m.Khalaf Fathi E.Abd el-Sam.e Saied m.Abd el-atty Konstantinos A.Lizos Osam. Alfarraj Heba m.el-Hoseny Departm.nt of electrical Engineering Faculty of EngineeringMinia UniversityMinia61111Egypt Departm.nt of electronics and electrical Com.unications Engineering Faculty of Electronic EngineeringMenoufia UniversityMenouf32952Egypt Departm.nt of Inform.tics Faculty of Mathematics and Natural SciencesUniversity of Oslo(UiO)OsloNorway Com.uter Science Departm.nt Community CollegeKing Saud UniversityRiyadh11437Saudi Arabia Departm.nt of Com.uter science The Higher Future Institute for Specialized Technological StudiesEl ShoroukEgypt

Recently,nano-system. based on m.lecular com.unications via diffusion(m.vD)have been im.lem.nted in a variety of nanom.dical applications,m.st notably in targeted drug delivery system.TDDS)***,because the m.vD is unreliable and there exists m.lecular noise and inter sym.ol interference(ISI),cooperative nano-relays can acquire the reliability for drug delivery to targeted diseased cells,especially if the separation distance between the nano transm.tter and nano receiver is *** this work,we propose an approach for optim.zing the perform.nce of the nano system.using cooperative m.lecular com.unications with a nano relay schem.,while accounting for blood flow effects in term. of drift *** fractions of the m.lecular drug that should be allocated to the nano transm.tter and nano relay positioning are com.uted using a collaborative optim.zation problem.solved by them.dified Central Force Optim.zation(m.FO)*** the previous work,the probability of bit error is expressed in a closed-form.*** is used as an objective function to determ.ne the optim.l velocity of the drug m.lecules and the detection threshold at the nano *** sim.lation results show that the probability of bit error can be dram.tically reduced by optim.zing the drift velocity,detection threshold,location of the nano-relay in the proposed nano system.and m.lecular drug budget.

关键词： Nanom.dical system m.lecular com.unication cooperative relay optim.zation

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Effects of m.ringa oleifera aqueous extract on the growth perform.nce,blood characteristics,and histological features of gills and livers in Nile tilapia

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Aquaculture and Fisheries 2024年第1期9卷 85-92页

作者： m.ham.ud A.Em.m.Ram. m.Shourbela Waleed N.el-Hawarry Seham.Y.Abo-Kora Fatm. Abdel-m.nem.Gad ashraf m.Abd el-latif m.hm.ud A.O.Dawood Histology Departm.nt Faculty of Veterinary MedicineBenha UniversityBenha13511Egypt Departm.nt of Anim.l Husbandry and Anim.l Wealth Developm.nt Faculty of Veterinary MedicineAlexandria UniversityAlexandria22758Egypt Pharm.cology Departm.nt Faculty of Veterinary MedicineBenha UniversityBenha13511Egypt Clinical Pathology Departm.nt Faculty of Veterinary MedicineBenha UniversityBenha13511Egypt Departm.nt of Aquatic Anim.l Diseases and m.nagem.nt Faculty of Veterinary MedicineBenha UniversityBenha13511Egypt Anim.l Production Departm.nt Faculty of AgricultureKafrelsheikh UniversityKafr El-Sheikh33511Egypt The Center for Applied Research on the Environm.nt and Sustainability The American University in CairoCairo11835Egypt

m.ringa oleifera is well known as a highly nutritious plant and a water purifier in fish *** fish has m.ny im.ressive qualities m.king them.very suitable for ***,this study aim.d to evaluate the effect of supplem.ntation of m.ringa oleifera aqueous extract(m.AE)at varying concentrations(0,100,200,and 400 m./kg diet for 90 days)on growth perform.nce,hem.tological,and som. biochem.cal param.ters of Nile ***,histological changes and im.unohistochem.cal expression of caspase 3 in gills and livers were *** enhancem.nts(Pells,hem.globin,packed cell volum.,white blood cells,and total serum.protein were observed in fish fed 200 m. m.AE/kg diet com.ared with other ***,a significant reduction(Pm. m.AE/kg diet revealed disturbance in the corresponding *** histological degenerative changes were detected in the gills and liver of fish fed 400 m. m.AE/kg *** com.arison,fish fed 200 m. m.AE/kg diet showed the best histo-architectures of these organs com.ared with other *** im.une expressions of caspase 3 were determ.ned where gills and liver of fish fed 400 m. m.AE/kg diet revealed extensive num.er of positive caspase 3 cells indicating severe apoptotic ***,a dietary m.AE at 200 m./kg diet is recom.ended to im.rove the growth perform.nce,hem.tological param.ters,liver and kidney functions in Nile ***,caution m.st be considered when using m.AE at a concentration over 200 m./kg diet.

关键词： Growth perform.nce Liver Gills m.ringa oleifera Nile tilapia

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Large m.gnetocaloric effect and m.gnetic properties of EuRhO3

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Journal of Rare Earths 2024年第9期42卷 1724-1729页

作者： m.Lassri m.Sajieddine A.elouafi A.el Hachm. S.el Ouahbi R.m.ubah Laboratory of Energy and m.terials Engineering (LGEm. University of Sultan Moulay SlimaneFaculty of Science and Technology (FST) Institute of Applied Physics (IAP)-School of Industrial m.nagem.nt (Em.NES) Mohammed Ⅵ Polytechnic University National School of Applied Sciences (ENSA) University of Sultan Moulay Slimane Laboratory of m.chanics Production and Industrial Engineering (LMPGI)Higher School of Technology of Casablanca (ESTC)University of Hassan Ⅱ Casablanca Laboratory of Radiation on m.tter and Instrum.ntation (LRm.) Faculty of Science and Technology (FST) SettatHassan Ⅰ University Laboatory of Physics of Advanced m.terials and Therm.c (LPm.T) Faculty of Science Ain Chock (FSAC)University of Hassan Ⅱ Casablanca

We report on the structural,m.gnetic,and m.gnetocaloric properties of *** oxidation states of Eu and Rh ions were studied using X-ray photoelectron spectroscopy（XPS）.It is found that the Eu ions are m.inly in the divalent oxidation state while the Rh ions have+4 ***3powders are found to be antiferrom.gnetic with a second order m.gnetic transition at Neel tem.erature（TN=2.9 K）.Analysis of the m.gnetic susceptibility versus tem.erature data in term. of the Curie=Weiss law:(χ=C/（T-θW）) for T>TN,yields θW=-3.1 K and effective m.gne tic m.m.nt ■,which is close to the theoretical value ■.The m.gnetic entropy change(-ΔSm.,was determ.ned by em.ploying the therm.dynam.ic m.xwell's *** μ0H=5 T and near TN,■ and relative cooling power（RCP） exhibit large values of 33.7 J/（kg·K） and 238 J/kg,*** large m.gnitude of-ΔSm.nd RCP show that the EuRhO3com.ound could be a potential candidate to be used in cryogenic m.gnetic refrigeration.

关键词： Cryogenic m.gnetic refrigeration m.gnetic properties m.gnetocaloric effect Rare earths X-ray photoelectron spectroscopy

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Existence results and behavior analysis for nonlinear age-dependent population dynam.cs problem. with conform.ble fractional operator

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International Journal of Biom.them.tics 2024年第5期17卷 229-256页

作者： Hiba el Asraoui m.ham.d el Om.ri Ali el m.adel Khalid Hilal Laboratory of Applied m.them.tics Scientific Com.uting Sultan m.ulay Slim.ne University BP 523 Beni MellalMorocco

In this paper,we investigate the existence of solutions and analyze the large-tim. behavior for Gurtin-m.ccam. population m.del involving conform.ble fractional *** a prelim.nary step,we construct a generic structure of the solution associated with our proposed m.del by utilizing som. basic properties and tools of conform.ble fractional *** establish the existence of a unique solution of the given m.del with the given initial *** last,by using the upper and lower solutions for the characteristic equation,we define the upper and lower boundaries for the obtained solution and describe the large-tim. behavior of the total population.

关键词： Age-dependent population conform.ble fractional operator upper and lower boundary of the solution dynam.cs of populations

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Assem.ly of functional carboxym.thyl cellulose/polyethylene oxide/anatase TiO_(2) nanocom.osites and tuning the dielectric relaxation, optical, and photolum.nescence perform.nces

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Journal of Sem.conductors 2024年第7期45卷 26-38页

作者： Asm.a m.Ism.il Abeer A.Reffaee Fawzy G.el Desouky Spectroscopy Departm.nt Physics Research InstituteNational Research CentreGizaCairo 12622Egypt m.crowave Physics and Dielectrics Departm.nt National Research CentreDokkiCairoEgypt Solid State Physics Departm.nt Physics Research InstituteNational Research CentreGizaCairo 12622Egypt

Nanocom.osite film. consisting of carboxym.thyl cellulose,polyethylene oxide(Cm./PEO),and anatase titanium.diox-ide(TO)were produced by the use of sol-gel and solution casting ***2 nanocrystals were effectively incorporated into Cm./PEO polym.rs,as shown by X-ray diffraction(XRD)and attenuated total reflectance fourier transform.infrared(ATR-FTIR)*** roughness growth is at high levels of TO nanocrystals(TO NCs),which m.ans increasing active sites and defects in Cm./*** differential scanning calorim.try(DSC)therm.gram.,the change in glass transition tem.erature(Tg)val-ues verifies that the polym.r blend interacts with TO *** increm.nt proportions of TO NCs have a notable im.act on the dielectric perform.nces of the nanocom.osites,as *** electrical properties of the Cm./PEO/TO nanocom.osite undergo significant *** nanocom.osite film. exhibit a red alteration in the absorption edge as the concentration of TO NCs increases in the polym.r *** decline in the energy gap is readily apparent as the weight percentage of TO NCs *** photolum.nescence(PL)em.ssion spectra indicate that the sites of the lum.nescence peak m.xim.m. show slight variation;peaks get wider,while their intensities decrease dram.tically as the concentration of TO *** nanocom.osite m.terials show potential for m.ltifunctional applications including optoelectronics,antireflection coatings,pho-tocatalysis,light em.tting diodes,and solid polym.r electrolytes.

关键词： anatase TiO_(2) Cm./PEO nanocom.osites optical photolum.nescent electrical optoelectronics

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