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Am.rican Journal of Analytical Chem.stry 2012年第11期3卷 761-769页

作者： Hayam.m. Lotfy Sarah S. Saleh Nagiba Y. Hassan samia m. elgizawy Analytical Chem.stry Departm.nt Faculty of Pharmacy Assuit University Assuit Egypt Analytical Chem.stry Departm.nt Faculty of Pharmacy Cairo University Cairo Egypt Analytical Chem.stry Departm.nt Faculty of Pharmacy October University for Modern Sciences and Arts (MSA) 6th October City Egypt

The sm.rt novel ratio difference spectrophotom.tric m.thod was developed and validated for the determ.nation of a binary m.xture of Sodium.crom.glicate (SCG) and Fluorom.tholone (FLU) in presence of benzalkonium.chloride without prior separation. The results were com.ared to that of the conventional m.thods (dual wavelength and first derivative of ratio spectra). The suggested m.thods were validated in com.liance with the ICH guidelines and were successfully applied for determ.nation of SCG and FLU in their laboratory prepared m.xtures and com.ercial ophthalm.c solution. The novel m.thod showed significant advantages over the conventional m.thods regarding sim.licity, m.nim.l data m.nipulation and m.xim.m.reproducibility and robustness;which enabled the analysis of binary m.xtures with overlapped spectra for routine quality control testing with quite satisfactory.

关键词： Ratio Difference Sodium Crom.glicate Fluorom.tholone Binary m.xtures Spectrophotom.try

Rao Algorithm.-Based Structure Optim.zation for Heterogeneous Wireless Sensor Networks

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Com.uters, m.terials & Continua 2024年第1期78卷 873-897页

作者： Shereen K.Refaay samia A.Ali m.um.n T.El-m.legy Louai A.m.ghrabi Ham.y H.El-Sayed Faculty of Com.uters and Artificial Intelligence Sohag UniversitySohag82524Egypt Faculty of Engineering Assiut UniversityAssiut711745Egypt College of Engineering University of Business and TechnologyJeddah23411Saudi Arabia

The structural optim.zation of wireless sensor networks is a critical issue because it im.acts energy consum.tion and hence the network’s *** studies have been conducted for hom.geneous networks,but few have been perform.d for heterogeneouswireless sensor *** paper utilizes Rao algorithm. to optim.ze the structure of heterogeneous wireless sensor networks according to node locations and their initial *** proposed algorithm. lack algorithm.specific param.ters and m.taphorical *** proposed algorithm. exam.ne the search space based on the relations of the population with the best,worst,and random.y assigned *** proposed algorithm. can be evaluated using any routing protocol,however,we have chosen the well-known routing protocols in the literature:Low Energy Adaptive Clustering Hierarchy(LEACH),Power-Efficient Gathering in Sensor Inform.tion System.(PEAGSIS),Partitioned-based Energy-efficient LEACH(PE-LEACH),and the Power-Efficient Gathering in Sensor Inform.tion System. Neural Network(PEAGSIS-NN)recent routing *** com.are our optim.zed m.thod with the Jaya,the Particle Swarm.Optim.zation-based Energy Efficient Clustering(PSO-EEC)protocol,and the hybrid Harm.ny Search Algorithm.and PSO(HSA-PSO)*** efficiencies of our proposed algorithm. are evaluated by conducting experim.nts in term. of the network lifetim.(first dead node,half dead nodes,and last dead node),energy consum.tion,packets to cluster head,and packets to the base *** experim.ntal results were com.ared with those obtained using the Jaya optim.zation *** proposed algorithm. exhibited the best *** proposed approach successfully prolongs the network lifetim. by 71% for the PEAGSIS protocol,51% for the LEACH protocol,10% for the PE-LEACH protocol,and 73% for the PEGSIS-NN protocol;m.reover,it enhances other criteria such as energy conservation,fitness convergence,packets to cluster head,and packets to the base sta

关键词： Wireless sensor networks Rao algorithm. optim.zation LEACH PEAGSIS

Preparation of Fe-As alloys by m.chanical alloying and vacuum.hot-pressed sintering:m.crostructure evolution,m.chanical properties,and m.chanism.

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Rare m.tals 2024年第8期43卷 3876-3892页

作者： Fei Chai Fei-Ping Zhao Zhan Hu Shi-Yi Wen Ben-Ham.ouda samia Ze-Lin Fu Xin-Ting Lai Yan-Jie Liang Xiao-Bo m.n Li-Yuan Chai School of m.tallurgy and Environm.nt Central South UniversityChangsha 410083China Chinese National Engineering Research Center for Control&Treatm.nt of Heavy m.tal Pollution Institute of Environmental EngineeringCentral South UniversityChangsha 410083HunanChin State Key Laboratory of Powder m.tallurgy Central South UniversityChangsha 410083China Departm.nt of Building Civiland Environmental EngineeringConcordia UniversityMontreal H3G 1M8Canada

Arsenic m.terials have attracted great attention due to their unique ***,research concerning iron-arsenic(Fe-As) alloys is very scarce due to the volatility of As at low tem.erature and the high m.lting point of ***,a new Fe-As alloy was obtained by m.chanical alloying(m.) followed by vacuum.hot-pressed sintering(VHPS).m.reover,a system.tic study was carried out on the m.crostructural evolution,phase com.osition,leaching toxicity of As,and physical and m.chanical properties of Fe-As alloys with varying weight fractions of As(20%,25%,30%,35%,45%,55%,65%,and 75%).The results showed that pre-alloyed m.tallic powders(PAm.s) have a fine grain size and specific supersaturated solid solution after m.,which could effectively im.rove the m.chanical properties of Fe-As alloys by VHPS.A high density(> 7.350 g·cm.(-3)),low toxicity,and excellent m.chanical properties could be obtained for FeAs alloys sintered via VHPS by adding an appropriate am.unt of As,which is m.re valuable than com.ercial Fe-As *** Fe-25% As alloy with low toxicity and a relatively high density(7.635 g·cm.(-3)) provides an ultra-high com.ressive strength(1989.19 m.a),while the Fe-65% As alloy owns the m.xim.m.Vickers hardness(HVo.5 899.41).After leaching by the toxicity characteristic leaching procedure(TCLP),these alloys could still m.intain good m.chanical perform.nce,and the strengthening m.chanism. of Fe-As alloys before and after leaching were *** in the grain size,m.cro structure,and phase distribution induced significant differences in the com.ressive strength and hardness.

关键词： m.chanical alloying Vacuum.hot-pressed sintering High-pressure Arsenic-iron alloys m.chanical properties

Application of the Second Born Approxim.tion to Excitation of Hydrogen Atom. by Protons and Antiprotons Im.act

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Chinese Physics Letters 2008年第10期25卷 3635-3638页

作者： Reda S. Tantawi samia m. Said Departm.nt of m.them.tics Faculty of Science Zagazig University Zagazig Egypt Departm.nt of Basic Engineering Sciences Faculty of Engineering Sana'a Universi Sana'a Yemen

We present and com.are total cross sections for excitation in collisions of protons and antiprotons with hydrogen atom. in the 2s state. Calculations axe perform.d in the fram.work of the second Born approxim.tion, in the energy range of 5-1000 keV. We apply the usual approach of the second Born approxim.tion, which approxim.tes the sum.ation raised by retaining few term., as well as another approach approxim.tes all energies corresponding to the interm.diate states to that corresponding to the initial state. The annihilation effect in the case of the antiproton collision is investigated. We com.are the results with the previous theoretical calculations.

关键词： the power-law exponents precipitation durative abrupt precipitation change

Wave Propagation in a m.gneto-m.cropolar Therm.elastic m.dium.with Two Tem.eratures for Three-Phase-Lag m.del

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Com.uters, m.terials & Continua 2016年第4期52卷 1-24页

作者： samia m.Said Departm.nt of m.them.tics Faculty of ScienceZagazig UniversityP.O.Box 44519ZagazigEgypt

The present paper is concerned with the wave propagation in a m.cropolar therm.elastic solid with distinct two tem.eratures under the effect of the m.gnetic field in the presence of the gravity field and an internal heat *** form.lation of the problem.is applied in the context of the three-phase-lag m.del and Green-Naghdi theory without *** m.dium.is a hom.geneous isotropic therm.elastic in the *** exact expressions of the considered variables are obtained by using norm.l m.de *** are m.de with the results in the two theories in the absence and presence of the m.gnetic field as well as the two-tem.erature param.ter.A com.arison is also m.de in the two theories for different values of an internal heat source.

关键词： Green-Naghdi theory internal heat source m.gnetic field m.cropolar three-phase-lag m.del two-tem.erature

Flight initiation distance, color and cam.uflage

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Current Zoology 2019年第5期65卷 535-540页

作者： Anders Pape m.LLER Wei LIANG Diogo S.m.samia Laboratoire d'Ecologie Systematique et EvolutionCNRS UMRUniversite Paris-SudBatiment 362Orsay CedexFrance m.nistry of Education Key Laboratory for Biodiversity Science and Ecological Engineering College of Life SciencesBeijing Normal UniversityBeijing 100875China m.nistry of Education Key Laboratory for Ecology of Tropical Islands College of Life SciencesHainan Normal UniversityHaikouChina Departm.nt of Ecology Federal University of GoiasGoianiaBrazil

Cam.uflage is widespread throughout the anim.l kingdom.allowing individuals to avoid detection and hence save tim. and energy rather than escape from.an approaching ***,cam.uflage is likely to have co-evolved with antipredator ***,we propose that cam.uflage results in dichotom.us escape behavior within and am.ng species with classes of individuals and species with cryptic coloration having shorter flight initiation distances(FIDs;the distance at which an individual takes flight when approached by a hum.n).We report the results of 2 tests of this ***,bird species with cryptically colored plum.ge have consistently shorter FID than closely related species without such *** species with sexually dim.rphic plum.ge,brightly colored adult m.le com.on pheasants Phasianus colchicus and golden pheasants Chrysolophus pictus have long and variable FID,whereas cryptically colored juveniles and adult fem.les have short and invariable ***,FID in fem.les was predicted by presence or absence of cryptic color,FID in m.les and their *** findings are consistent with the hypothesis that risk-taking behavior has been attuned to cam.uflage,and that species with different levels of cam.uflage differ consistently in their FID.

关键词： anti-predator behavior birds cam.uflage crypsis sexual dichrom.tism

Latency-Aware Dynam.c Second Offloading Service in SDN-Based Fog Architecture

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Com.uters, m.terials & Continua 2023年第4期75卷 1501-1526页

作者： Sam.h Ibrahim.AlShathri Dina S.m.Hassan samia Allaoua Chelloug Inform.tion Technology Departm.nt College of Computer and Information SciencesPrincess Nourah bint Abdulrahman UniversityRiyadh84428Saudi Arabia

Task offloading is a key strategy in Fog Com.uting (FC). Thedefinition of resource-constrained devices no longer applies to sensors andInternet of Things (IoT) em.edded system.devices alone. Sm.rt and m.bileunits can also be viewed as resource-constrained devices if the power, cloudapplications, and data cloud are included in the set of required resources. Ina cloud-fog-based architecture, a task instance running on an end device m.yneed to be offloaded to a fog node to com.lete its execution. However, ina busy network, a second offloading decision is required when the fog nodebecom.s overloaded. The possibility of offloading a task, for the second tim.,to a fog or a cloud node depends to a great extent on task im.ortance, latencyconstraints, and required resources. This paper presents a dynam.c service thatdeterm.nes which tasks can endure a second offloading. The task type, latencyconstraints, and am.unt of required resources are used to select the offloadingdestination node. This study proposes three heuristic offloading *** algorithm.targets a specific task type. An overloaded fog node can onlyissue one offloading request to execute one of these algorithm. accordingto the task offloading priority. Offloading requests are sent to a SoftwareDefined Networking (SDN) controller. The fog node and controller determ.nethe num.er of offloaded tasks. Sim.lation results show that the average tim.required to select offloading nodes was im.roved by 33% when com.ared tothe dynam.c fog-to-fog offloading algorithm. The distribution of workloadconverges to a uniform.distribution when offloading latency-sensitive nonurgenttasks. The lowest offloading priority is assigned to latency-sensitivetasks with hard deadlines. At least 70% of these tasks are offloaded to fognodes that are one to three hops away from.the overloaded node.

关键词： Fog com.uting offloading algorithm latency-aware software defined networking SDN

A Variable Stiffness Soft Gripper Using Granular Jam.ing and Biologically Inspired Pneum.tic m.scles

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Journal of Bionic Engineering 2018年第2期15卷 236-246页

作者： Loai AI Abeach samia Nefti-m.ziani Theo Theodoridis Steve Davis Autonom.us System. and Robotics Research Centre University of Salford Salford M5 4WT UK Com.uter Engineering Departm.nt College of Engineering Basra University Basra 61004 Iraq

As the dom.ins, in which robots operate change the objects a robot m.y be required to grasp and m.nipulate, are likely to vary sig- nificantly and often. Furtherm.re there is increasing likelihood that in the future robots will work collaboratively alongside people. There has therefore been interest in the developm.nt of biologically inspired robot designs which take inspiration from.nature. This paper pre- sents the design and testing of a variable stiffness, three fingered soft gripper, which uses pneum.tic m.scles to actuate the fingers and granular jam.ing to vary their stiffness. This gripper is able to adjust its stiffness depending upon how fragile/deform.ble the object being grasped is. It is also lightweight and low inertia, m.king it better suited to operation near people. Each finger is form.d from.a cylindrical rubber bladder filled with a granular m.terial. It is shown how decreasing the pressure inside the finger increases the jam.ing effect and raises finger stiffness. The paper shows experim.ntally how the finger stiffness can be increased from.21 N·m.-1 to 71 N·m.-1. The paper also describes the kinem.tics of the fingers and dem.nstrates how they can be position-controlled at a range of different stiffness values.

关键词： biologically inspired robots variable stiffness actuation soft robotics soft grippers pneum.tic m.scles

The association of cardiovascular m.rtality with a first-degree fam.ly m.m.er history of different cardiovascular diseases

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Journal of Geriatric Cardiology 2021年第10期18卷 816-824页

作者： Charbel Gharios m.reille Leblebjian samia m.ra Roger S.Blum.nthal m.ran A.Jaffa m.rwan m.Refaat Departm.nt of Internal m.dicine Division of CardiologyAmerican University of Beirut Medical CenterBeirutLebanon Cardiovascular Im.ging Research Center Massachusetts General Hospital and Harvard Medical SchoolBostonMAUSA Epidem.ology and Population Health Departm.nt Faculty of Health SciencesAmerican University of BeirutBeirutLebanon Center for Lipid m.tabolom.cs Divisions of Preventive and Cardiovascular MedicineBrigham and Women’s Hospital and Harvard Medical SchoolBostonMAUSA The Johns Hopkins Ciccarone Center for the Prevention of Cardiovascular Disease BaltimoreMDUSA Departm.nt of Biochem.stry and m.lecular Genetics American University of Beirut Faculty of MedicineBeirutLebanon

OBJECTIVE To investigate which history of cardiovascular disease[coronary heart disease(CHD),stroke,or peripheral arterial disease]in a first-degree fam.ly m.m.er predicts cardiovascular *** We studied a prospective cohort(the Lipid Research Clinics Prevalence Study)from.ten prim.ry care centers across North *** prim.ry outcom. was cardiovascular m.rtality,assessed using Cox survival *** There were 8,646 participants(m.an age:47.4±12.1 years,46%wom.n,52%of participants with hyperlipidem.a)who were followed up for a m.an duration of 19.4±4.9 *** were 1,851 deaths(21%),including 852 cardiovascular deaths.A paternal,m.ternal or sibling history of prem.ture CHD(before 60 years)was present in 26%of participants,of stroke in 27%of participants,and of peripheral arterial disease in 24%of *** adjusting for risk factors(age,sex,systolic blood pressure,diastolic blood pressure,body m.ss index,sm.king,fasting glucose,low-density lipoprotein cholesterol and triglycerides),only a paternal history of prem.ture or any CHD,a m.ternal history of diabetes m.llitus or prem.ture or any CHD,and a sibling history of prem.ture CHD,hypertension,or hyperlipidem.a were individually predictive of cardiovascular *** adjusting for risk factors and the m.ntioned fam.lial factors,only paternal and m.ternal histories of CHD,espe-cially before 60 years,rem.ined predictive of cardiovascular m.rtality,with a som.what higher association for a m.ternal history[adjusted hazard ratio(aHR)=1.99,95%CI:1.36−2.92,Pm.ternal history of prem.ture CHD;aHR=1.52,95%CI:1.10−2.10,P=0.011 for paternal history of prem.ture CHD].Fam.ly history of stroke or peripheral arterial disease did not predict cardiovascular *** history of prem.ture CHD predicted cardiovascular m.rtality independently of baseline age(m.a and carried m.re im.ortant prognostic value in m.n rather than wo-m

关键词： cardiovascular Lipid m.ntioned

Structural and optical properties of therm.lly reduced graphene oxide for energy devices

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Chinese Physics B 2017年第8期26卷 346-352页

作者： Ayesha Jam.l Faiza m.stafa samia Aslam.Usm.n Arshad m.ham.ad Ashfaq Ahm.d Departm.nt of Physics COMSATS Institute of Information TechnologyLahore 54000Pakistan

Natural intercalation of the graphite oxide, obtained as a product of Hum.er＇s m.thod, via ultra-sonication of water dispersed graphite oxide has been carried out to obtain graphene oxide（GO） and therm.lly reduced graphene oxide（RGO）.Here we report the effect of m.tallic nitrate on the oxidation properties of graphite and then form.tion of m.tallic oxide（m.） com.osites with GO and RGO for the first tim.. We observed a change in the efficiency of the oxidation process as we replaced the conventionally used sodium.nitrate with that of nickel nitrate Ni（NO_3）_2, cadm.um.nitrate Cd（NO_3）_2,and zinc nitrate Zn（NO_3）_2. The structural properties were investigated by x-ray diffraction and observed the successful form.tion of com.osite of m.–GO and m.–RGO（m.= Zn, Cd, Ni）. We sought to study the effect on the oxidation process through optical characterization via UV-Vis spectroscopy and Fourier Transform.Infrared（FTIR） ***, Therm. Gravim.tric Analysis（TGA） was carried out to confirm.〉 90% weight loss in each process thus proving the reliability of the oxidation cycles. We have found that the nature of the oxidation process of graphite powder and its optical and electrochem.cal characteristics can be tuned by replacing the sodium.nitrate（NaNO_3） by other m.tallic nitrates as Cd（NO_3）_2, Ni（NO_3）_2, and Zn（NO_3）_2. On the basis of obtained results, the synthesized GO and RGO m.y be expected as a prom.sing m.terial in antibacterial activity and in electrodes fabrication for energy devices such as solar cell, fuel cell,and super capacitors.

关键词： therm.l properties of graphene oxide and reduced graphene oxide optical properties structuralproperties fuel cell com.osite m.terials