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Observed Enhancement in LIBS Signals from Nano vs. Bulk ZnO Targets: Comparative Study of Plasma Parameters

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 Sami H. Allam ashraf el dakrouri Tharwtt M. el Sherbini Collage of Applied Medical Science King Saud University KSA & the National Institute of Laser Enhanced Sciences Cairo University Giza Egypt Department of Laser and Opto-electronic Engineering University of Technology Baghdad Iraq Department of Physics Laboratory of Lasers and New Materials Faculty of Science Cairo University Giza Egypt

In this article, we will report an experimental evidence of enhanced LIBS emission upon replacing a Bulk-Based ZnO target by the corresponding Nano-Based target. The plasma was initiated via interaction of a Nd:YAG laser at the fundamental wavelength with both targets in open air under the same experimental conditions. The measurements show an enhanced emission 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 measurements were repeated at different delay times in the range from 1 to 5 μs at constant irradiation level and fixed gate time of 1 μs. The average enhancement over the different Zn I-lines was found increases exponentially up to 8-fold with delay time. The electron density to each plasma was measured utilizing the Hα-line appeared in the emitted spectra from each plasma and was found to give similar values. The electron temperatures were measured via Boltzmann plot method utilizing the relative intensities of the Zn I-lines and were found to give very close values. Moreover, the relative population density of the ground state of the zinc atoms (relative concentration) was measured spectroscopically utilizing the Boltzmann plot method and was found to increase in a very similar trend to that of enhancement. The results of the spectroscopic analysis conclude that these signal enhancements can be attributed to the higher concentration of neutral atoms in the Nano-Based material plasma with respect to the corresponding Bulk-based ZnO material.

关键词： LIBS Enhancement ZnO Nonmaterial Hα-Line Zn I-Lines Spectroscopy

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Spectroscopic measurement of Stark broadening parameter 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 Sami H. Allam Ahmed M. Al-Kaoud ashraf el dakrouri Tharwat M. el Sherbini College of Applied Medical Sciences King Saud University Riyadh KSA Department of Laser and Opto-electronic Engineering University of Technology Baghdad Iraq Department of Physics Collage of Science AL-Imam Muhammad Ibn Saud Islamic University (AIMSIU) Al Riyadh KSA Department of Physics Laboratory of Lasers and New Materials Faculty of Science Cairo University Giza Egypt

In this article we will present an attempt to measure the Stark broadening parameter of the Zn I-line at 636.23 nm utilizing the optical emission spectroscopy (OES) technique, taking into consideration the possibility of existence of self absorption. This method is standing on comparison of the Lorentzian FWHM and spectral line intensity of the unknown Stark broadening parameter line (Zn I-636.23 nm—in our case) to a well known Stark parameter 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 temperature of 1 eV. We have utilized the emission spectral data acquired from well diagnosed plasma produced by the interaction of Nd: YAG laser at wavelength of 1064 nm with ZnO nanomaterial 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 plasma parameters. The knowledge of the Stark broadening parameter of the 636.23 nm line may be important in the diagnostics of the laser plasma experiments especially in the absence of the Hα-line.

关键词： Stark Broadening Parameter LIBS OES ZnO Zinc Lines

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Optimization of Cooperative RelayingMolecular Communications for Nanomedical Applications

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Computer Modeling in Engineering & Sciences 2024年第2期138卷 1259-1275页

作者： Eman S.Attia ashraf A.M.Khalaf Fathi E.Abd el-Samie Saied M.Abd el-atty Konstantinos A.Lizos Osama Alfarraj Heba M.el-Hoseny Department of electrical Engineering Faculty of EngineeringMinia UniversityMinia61111Egypt Department of electronics and electrical Communications Engineering Faculty of Electronic EngineeringMenoufia UniversityMenouf32952Egypt Department of Informatics Faculty of Mathematics and Natural SciencesUniversity of Oslo(UiO)OsloNorway Computer Science Department Community CollegeKing Saud UniversityRiyadh11437Saudi Arabia Department of Computer science The Higher Future Institute for Specialized Technological StudiesEl ShoroukEgypt

Recently,nano-systems based on molecular communications via diffusion(MCvD)have been implemented in a variety of nanomedical applications,most notably in targeted drug delivery system(TDDS)***,because the MCvD is unreliable and there exists molecular noise and inter symbol interference(ISI),cooperative nano-relays can acquire the reliability for drug delivery to targeted diseased cells,especially if the separation distance between the nano transmitter and nano receiver is *** this work,we propose an approach for optimizing the performance of the nano system using cooperative molecular communications with a nano relay scheme,while accounting for blood flow effects in terms of drift *** fractions of the molecular drug that should be allocated to the nano transmitter and nano relay positioning are computed using a collaborative optimization problem solved by theModified Central Force Optimization(MCFO)*** the previous work,the probability of bit error is expressed in a closed-form *** is used as an objective function to determine the optimal velocity of the drug molecules and the detection threshold at the nano *** simulation results show that the probability of bit error can be dramatically reduced by optimizing the drift velocity,detection threshold,location of the nano-relay in the proposed nano system,and molecular drug budget.

关键词： Nanomedical system molecular communication cooperative relay optimization

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Effects of Moringa oleifera aqueous extract on the growth performance,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： Mahamoud A.Emam Ramy M.Shourbela Waleed N.el-Hawarry Seham Y.Abo-Kora Fatma Abdel-Monem Gad ashraf M.Abd el-latif Mahmoud A.O.Dawood Histology Department Faculty of Veterinary MedicineBenha UniversityBenha13511Egypt Department of Animal Husbandry and Animal Wealth Development Faculty of Veterinary MedicineAlexandria UniversityAlexandria22758Egypt Pharmacology Department Faculty of Veterinary MedicineBenha UniversityBenha13511Egypt Clinical Pathology Department Faculty of Veterinary MedicineBenha UniversityBenha13511Egypt Department of Aquatic Animal Diseases and Management Faculty of Veterinary MedicineBenha UniversityBenha13511Egypt Animal Production Department Faculty of AgricultureKafrelsheikh UniversityKafr El-Sheikh33511Egypt The Center for Applied Research on the Environment and Sustainability The American University in CairoCairo11835Egypt

Moringa oleifera is well known as a highly nutritious plant and a water purifier in fish *** fish has many impressive qualities making them very suitable for ***,this study aimed to evaluate the effect of supplementation of Moringa oleifera aqueous extract(MOAE)at varying concentrations(0,100,200,and 400 mg/kg diet for 90 days)on growth performance,hematological,and some biochemical parameters of Nile ***,histological changes and immunohistochemical expression of caspase 3 in gills and livers were *** enhancements(Pells,hemoglobin,packed cell volume,white blood cells,and total serum protein were observed in fish fed 200 mg MOAE/kg diet compared with other ***,a significant reduction(Pells indicating severe apoptotic ***,a dietary MOAE at 200 mg/kg diet is recommended to improve the growth performance,hematological parameters,liver and kidney functions in Nile ***,caution must be considered when using MOAE at a concentration over 200 mg/kg diet.

关键词： Growth performance Liver Gills Moringa oleifera Nile tilapia

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Comparison between seismic analysis of twisting and regular 52-story towers considering soil-structure interaction

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Earthquake Engineering and Engineering Vibration 2024年第3期23卷 663-675页

作者： Mohamed Naguib Abouelsaad Mohammed Shaaban Salah el Bagalaty Mohamed E.el Madawy Structural Engineering Department Faculty of EngineeringMansura UniversityMansoura 35511Egypt Faculty of Engineering Delta University for Science and TechnologyGamasa 35712Egypt

A dynamic analysis of both twisting and regular towers is carried out to determine the results of considering soil-structure interaction(SSI)on high-rise *** addition,the difference between the seismic performance of using twisting towers over regular ones is *** twisting tower is a simulation of the Evolution Tower(Moscow).The towers’skeletons consist of RC elements and rest on a reinforced concrete piled-raft *** soil model is considered as multi-layered with the same soil properties as the zone chosen for the analysis(New Mansoura City,Egypt).The only difference between both towers is their shape in *** whole system is modelled and analyzed in a single step as one full 3D model,which is known as the direct approach in *** analyses are carried out using finite-element software(Midas GTS NX).Dynamic output responses due to three records of seismic loads are proposed and presented in some *** on the results,it is concluded that SSI has a considerable effect on the dynamic response of tall buildings mainly because of the foundation flexibility,as it leads to lengthening the vibration period,increasing the story drift and the base shear for both cases.

关键词： soil-structure interaction seismic analysis twisting towers base shear story drift finite element method Midas GTS NX

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Gender-Based Analysis of User Reactions to Facebook Posts

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Big Data Mining and Analytics 2024年第1期7卷 75-86页

作者： Yassine el Moudene Jaafar Idrais Rida el Abassi Abderrahim Sabour Mathematical Engineering and Computer Science Laboratory Faculty of SciencesIbn Zohr UniversityAgadir 8706Morocco Department of Computer Science Mathematical−High School of Technology Ibn Zohr UniversityAgadir 8706Morocco

Online Social Networks(OSNs)are based on the sharing of different types of information and on various interactions(comments,reactions,and sharing).One of these important actions is the emotional reaction to the *** diversity of reaction types available on Facebook(namely FB)enables users to express their feelings,and its traceability creates and enriches the users’emotional identity in the virtual *** paper is based on the analysis of 119875012 FB reactions(Like,Love,Haha,Wow,Sad,Angry,Thankful,and Pride)made at multiple levels(publications,comments,and sub-comments)to study and classify the users’emotional behavior,visualize the distribution of different types of reactions,and analyze the gender impact on emotion *** of these can be achieved by addressing these research questions:who reacts the most?Which emotion is the most expressed?

关键词： profiling knowledge extraction data mining emotion mining social media data crawling Facebook reactions gender

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Stability analysis of a time-delayed Van der Pol–Helmholtz–Duffing oscillator in fractal space with a non-perturbative approach

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Communications in Theoretical Physics 2024年第4期76卷 22-31页

作者： Yusry O el-Dib Department of Mathematics Faculty of EducationAin Shams UniversityRoxyCairoEgypt

The time-delayed fractal Van der Pol–Helmholtz–Duffing(VPHD)oscillator is the subject of this paper,which explores its mechanisms and highlights its stability *** time-delayed technologies are currently garnering significant attention,the focus of this research remains crucially relevant.A non-perturbative approach is employed to refine and set the stage for the system under *** innovative methodologies introduced yield an equivalent linear differential equation,mirroring the inherent nonlinearities of the ***,the incorporation of quadratic nonlinearity into the frequency formula represents a cutting-edge *** analytical solution's validity is corroborated using a numerical *** conditions are ascertained through the residual Galerkin ***,it is observed that the delay parameter,in the context of the fractal system,reverses its stabilizing influence,impacting both the amplitude of delayed velocity and the *** analytical solution's precision is underscored by its close alignment with numerical ***,the study reveals that fractal characteristics emulate damping *** its applicability across diverse nonlinear dynamical systems,this non-perturbative approach emerges as a promising avenue for future research.

关键词： Van der Pol-Helmholtz-Duffing oscillator fractal space time-delay non-perturbative approach stability analysis el-Dib's frequency formula

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Nonlinear wave dispersion in monoatomic chains with lumped and distributed masses:discrete and continuum models

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Applied Mathematics and Mechanics(English Edition) 2024年第4期45卷 633-648页

作者： E.GHAVANLOO S.el-BORGI School of Mechanical Engineering Shiraz UniversityShiraz 71963-16548Iran Mechanical Engineering Program Texas A&M University at QatarDoha 23874Qatar

The main objective of this paper is to investigate the influence of inertia of nonlinear springs on the dispersion behavior of discrete monoatomic chains with lumped and distributed *** developed model can represent the wave propagation problem in a non-homogeneous material consisting of heavy inclusions embedded in a *** inclusions are idealized by lumped masses,and the matrix between adjacent inclusions is modeled by a nonlinear spring with distributed ***,the model is capable of depicting the wave propagation in bi-material bars,wherein the first material is represented by a rigid particle and the second one is represented by a nonlinear spring with distributed *** discrete model of the nonlinear monoatomic chain with lumped and distributed masses is first considered,and a closed-form expression of the dispersion relation is obtained by the second-order Lindstedt-Poincare method(LPM).Next,a continuum model for the nonlinear monoatomic chain is derived directly from its discrete lattice model by a suitable continualization *** subsequent use of the second-order method of multiple scales(MMS)facilitates the derivation of the corresponding nonlinear dispersion relation in a closed *** novelties of the present study consist of(i)considering the inertia of nonlinear springs on the dispersion behavior of the discrete mass-spring chains;(ii)developing the second-order LPM for the wave propagation in the discrete chains;and(iii)deriving a continuum model for the nonlinear monoatomic chains with lumped and distributed ***,a parametric study is conducted to examine the effects of the design parameters and the distributed spring mass on the nonlinear dispersion relations and phase velocities obtained from both the discrete and continuum *** parameters include the ratio of the spring mass to the lumped mass,the nonlinear stiffness coefficient of the spring,and the wave amplitude.

关键词： nonlinear mass-spring chain discrete model continuum model LindstedtPoincare method(LPM) method of multiple scales(MMS) dispersion phase velocity

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Modeling environmental sensitivity and risk assessment of PAHs in sediments along two marine coastal areas in Egypt

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Petroleum Research 2024年第1期9卷 125-142页

作者： Muhammad A.el-Alfy National Institute of Oceanography and Fisheries NIOFCairoEgypt

Modeling the environmental sensitivity index(ESI)is vital in the planning and management processes,especially along the coastal *** main objectives of the study were to define the main sources of polycyclic aromatic hydrocarbons(PAHs),establish an ESI model,and measure the risk of PAHs on humans and the environment using various *** methodology of the research involved analyzing PAHs according to the EPA 550 methodology in sediments of the coastline in two important coastline areas in Egypt,namely the Gulf of Suez and the Mediterranean Sea,modeling the sensitivity of PAHs using ArcGIS 10.5 by integrating different physical,biological,and land use/cover factors,identifying the sources,and performing a risk *** sediment samples were collected from each *** produced sensitivity map could explain the highly sensitive areas along the Mediterranean Sea and Gulf of Suez coastlines(especially areas that were near drains'outlets,industrial sites,and sea ports).The highest mean PAH concentrations were Acenaphthylene and Fluorine in the Mediterranean Sea and Suez Gulf,***'s obvious that the individual PAH concentrations were within the ERL,ERM,and Pel threshold limits,indicating no adverse biological *** ratios of BaA/BaA+Chy,Flu/Flu+Py,and Ant/Ant+Phe gave an indication that most PAH sources were petrogenic(63.64%)and others(36.36%)were from petroleum *** principle component analysis(PCA)indicated a diverse correlation among the isomer ratios and LU/LC *** carcinogenic risk values were in the very low category(elines and seawater free of oil spillage act

关键词： Polycyclic aromatic hydrocarbons(PAHs) Modeling Sensitivity Gulf of Suez And Mediterranean sea

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Detection of internal crack growth in polyethylene pipe using guided wave ultrasonic testing

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Earthquake Engineering and Engineering Vibration 2024年第2期23卷 319-329页

作者： Jay Kumar Shah Hao Wang Said el-Hawwat Centre of Advanced Infrastructure and Transportation RutgersThe State University of New JerseyNJ 08854USA Department of Civil and Environmental Engineering RutgersThe State University of New JerseyNJ 08854USA

Despite the success of guided wave ultrasonic inspection for internal defect detection in steel pipes,its application on polyethylene(PE)pipe remains relatively *** growth of internal cracks in PE pipe severely affects its pressure-holding capacity,hence the early detection of internal cracks is crucial for effective pipeline maintenance *** study extends the scope of guided wave-based ultrasonic testing to detect the growth of internal cracks in a natural gas distribution PE *** experiments and a finite element model were planned to study the wave-crack interaction at different stages of axially oriented internal crack growth with a piezoceramic transducer-based setup arranged in a pitch-catch *** dispersion analysis supplemented with preliminary experiments was performed to isolate the optimal inspection frequency,leading to the selection of the T(0,1)mode at 50-kHz for the investigation.A transmission index based on the energy of the T(0,1)mode was developed to trace the extent of simulated crack *** findings revealed an inverse linear correlation between the transmission index and the crack depth for crack growth beyond 20%crack depth.

关键词： polyethylene pipes internal cracks guided wave ultrasonic testing torsional modes finite element modeling

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