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Particuology 2017年第5期15卷 61-69页

作者： m. helal uddin Charles J. Coronella Departm.nt of Chem.cal and m.terials Engineering University of Nevada Reno NV 89557 USA

Num.rical sim.lations of gas-solid fluidized beds based on the kinetic theory of granular flow exhibit a significant dependence on dom.in discretization. Bubble form.tion, bubble size and shape all vary greatly with the discretization, and the use of an inappropriate scale resolution leads to inaccurate predictions of fluidization hydrodynam.cs. In this study, grid-independent solutions of the two fluid m.del were exam.ned by com.aring the bed expansions obtained from.num.rical sim.lations with experim.ntal results and em.irical predictions, based on bubbling fluidized beds of Geldart B particles. Grid indepen- dence was achieved with a grid resolution equal to 18 tim.s the particle diam.ter. The sim.lation results were com.ared with previously published data for verification purposes. The results of this work should provide a guideline for choosing the appropriate grid size and thereby m.nim.ze the tim. and expense associated with large sim.lations.

关键词： m.sh effectHydrodynam.csCom.utational fluid dynam.csEuler-Euler m.thod m.IX

Regulating m.crostructure and com.osition by carbonizing in-situ grown m.tal-organic fram.works on cotton fabrics for boosting electrom.gnetic wave absorption

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Nano Research 2024年第8期17卷 7290-7300页

作者： Jie Jin Hongsen Long Hu Liu Yan Guo Tiantian Bai Ben Bin Xu m.ham.ed A.Am.n Hua Qiu m.ham.d H.helal Chuntai Liu Changyu Shen Zeinhom.m.El-Bahy Zhanhu Guo State Key Laboratory of Structural Analysis Optimization and CAE Software for Industrial EquipmentNational Engineering Research Center for Advanced Polymer Processing TechnologyZhengzhou UniversityZhengzhou 450002China China State Key Laboratory of Powder m.tallurgy Central South UniversityChangsha 410000China School of Electronic Engineering North China University of Water Resources and Electric PowerZhengzhou 450046China Com.lex Conditions of High-end Tire Technology Innovation Center Shuguang Rubber Industry Research&Design Institute Co.LtdGuilin 541004China Integrated Com.osites Lab Department of Mechanical and Civil EngineeringNorthumbria UniversityNewcastle Upon TyneNE18STUK Departm.nt of Chem.stry College of ScienceTaif UniversityP.O.Box 11099Taif 21944Saudi Arabia Shaanxi Key Laboratory of m.crom.lecular Science and Technology School of Chemistry and Chemical EngineeringNorthwestern Polytechnical UniversityXi’an 710072China Departm.nt of Chem.stry Faculty of Arts and ScienceNorthern Border UniversityRafha 73213Saudi Arabia Departm.nt of Chem.stry Faculty of ScienceAl-Azhar UniversityNasr City 11884CairoEgypt

High-tem.erature carbonized m.tal-organic fram.works(m.Fs)derivatives have dem.nstrated their superiority for prom.sing electrom.gnetic wave(Em.)absorbers,but they still suffer from.lim.ted Em. absorption capacity and narrow *** the advantage of m.crostructure and chem.cal com.osition regulation for the design of Em. absorber,hierarchical heterostructured m.S_(2)/CoS_(2)-Co_(3)O_(4)@cabonized cotton fabric(CF)(m.C@CCF)is prepared by growing ZIF-67 m.Fs onto CF surface,chem.cal etching,and *** from.the dual loss m.chanism.of m.gnetic-dielectric m.lticom.onent carbonized m.Fs,chem.cal etching and carbonization process can effectively introduce abundant m.cro-gap structure that can result in better im.edance m.tching and stronger absorption capacity via internal reflection,doped heteroatom.(m.,N,S)to supply additional dipolar polarization loss,and num.rous heterointerfaces am.ng m.S_(2),CoS_(2),Co_(3)O_(4),and CCF that produce prom.ted conduction loss and interfacial polarization ***,a m.nim.l reflection loss of−52.87 dB and a broadest effective absorption bandwidth of 6.88 GHz were achieved via tunning the sam.le thickness and filler loading,showing excellent Em. absorption *** research is of great value for guiding the research on m.Fs derivatives based Em. absorbing m.terials.

关键词： m.tal-organic fram.works hierarchical structure chem.cal etching sulfurization electrom.gnetic wave absorption

Biochem.cal Liver Functions and m.lecular Identification of Fasciola hepatica from.Experim.ntally Infected Rat m.del

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Open Journal of Anim.l Sciences 2024年第2期14卷 88-100页

作者： Om.ia m. Kandil Em.d B. Ata m.rgarita P. Gabrashanska Hatem.A. Shalaby Tam.r H. Abd El-Aziz Noha m. F. Hassan Soad m. Nasr m.ham.d A. helal Ebtesam.m. Al-Olayan Departm.nt of Parasitology & Anim.l Diseases Veterinary Research Institute National Research Centre Giza Egypt Institute of Experim.ntal m.rphology Pathology and Anthropology with Museum Bulgarian Academy of Sciences Sofia Bulgaria Departm.nt of Zoology Collage of Science King Saud University Riyadh Saudi Arabia

The current study was perform.d to evaluate the liver function status as well as m.lecular characterization of the recovered worm. in rats experim.ntally infected with F. hepatica. Sixteen m.le Wister rats aged 30 days were random.y allocated into two groups (n = 8). The first group was infected orally with 15 viable encysted m.tacercaria of F. hepatica per anim.l. The other group was kept non-infected (control group). At zero tim. (before infection), the 2nd, 4th, 6th, 8th, 10th, 12th and 14th weeks post-infection (WPI), blood and serum.sam.les were collected via puncture of retro-orbital plexus of veins from.each rat. Serum.enzym. level (AST and ALT) and total protein were m.asured, and the serum.protein profile was carried out using agarose gel electrophoresis. During the period of the experim.nt, serum.ALT and AST activities and serum.total globulins significantly increased while serum.total proteins and album.n m.rkedly decreased in the infected group. On the 14th WPI, the data of the electropherogram.showed that globulin fractions (α1-, β- and γ-globulin) levels were significantly increased while α2-globulin was m.rkedly decreased in the infected group. The m.lecular analysis confirm.d the am.lification of the ITS1, ITS2 and NDI genes of F. hepatica recovered from.the infected liver of rats with am.licon sizes of 630, 510 and 560 bp, respectively. Sequencing of the am.lified ITS gene resulted in the determ.nation of 3 strains (PP108836, PP108837, and PP108838). Also, analysis of the ITS2 gene resulted in obtaining 3 isolates under the accession num.ers (PP109065, PP109066, and PP109067). In conclusion, fasciolosis in the rat m.del is suitable for routine experim.ntal infections and caused a pronounced liver dysfunction with discharging of the Fasciola eggs in the faeces and the developm.nt of adult stages in the bile ducts. Furtherm.re, m.lecular techniques are a sensitive

关键词： Fasciola hepatica Liver Functions Serum.Enzym.s Serum.Protein Electrophoresis m.lecular Characterization

A new approach for fuel injection into a solar receiver/ reactor:Num.rical and experim.ntal investigation

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Frontiers of Chem.cal Science and Engineering 2018年第4期12卷 683-696页

作者： m.helal uddin Nesrin Ozalp Jens Heylen Cedric Ophoff m.chanical and Industrial Engineering Departm.nt University of Minnesota DuluthDuluthMN 55812-3042USA m.chanical Engineering Departm.nt 3001 LeuvenBelgium

An innovative and efficient design of solar receivers/reactors can enhance the production of clean fuels via concentrated solar energy. This study presents a new jet-type burner nozzle for gaseous feedstock injection into a cavity solar receiver inspired from.the com.ustion technology. The nozzle design was adapted from.a com.ustion burner and successfully im.lem.nted into a solar receiver and studied the influence of the nozzle design on the fluid m.xing and tem.erature distribution inside the solar receiver using a 7 kW solar sim.lator and nitrogen as working fluid. Finally, a thorough com.utational fluid dynam.cs (CFD) analysis was perform.d and validated against the experim.ntal results. The CFD results showed a variation of the gas flow pattern and gas m.xing after the burner nozzle adaptation, which resulted an intense effect on the heat transfer inside the solar receiver.

关键词： solar reactor nozzle CFD heat transfer m.xing and recirculation Clean fuels solar receivers nozzles Fuel injection com.utational fluid dynam.cs Heat transfer charge flow devices com.ustion technology m.xing of gases FLOW PATTERNS

Epidem.ological and histopathological characteristics of thyroid carcinom. in a Tunisian health care center

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World Journal of Otorhinolaryngology-Head and Neck Surgery 2024年第1期10卷 37-42页

作者： m.issa Ben Thayer Fatm. Khanchel Im.n helal Dorra Chiboub Hedhli Raoueh Ehsen Ben Brahim.Raja Jouini Aschraf Chadli-Debbiche Faculty of m.dicine of Tunis Tunis El Manar UniversityTunisTunisia Depatm.nt of Pathology Habib Thameur's HospitalTunisTunisia Departm.nt of Otorhinolaryngology-Head and Neck surgery Habib Thameur's HospitalTunisTunisia

Background:Thyroid carcinom.(TC)accounts for alm.st 0.5%–1%of total *** incidence is increasing rapidly *** studies have drawn up the epidem.ological profile of TC and its clinical and pathological ***,to date,no sim.lar studies have been conducted in ***:To establish an epidem.ological profile of TC in a Tunisian health care institute and to analyze its clinical and histopathological characteristics in our *** and m.thods:We present a retrospective study reviewing the cases of TC diagnosed in our institution in a 4-year ***:We collected a sam.le of 192 cases of *** consisted of 31 m.les and 161 fem.les(83.8%)with a sex-ratio m.F of *** m.an age was 46.4 *** thyroid carcinom. was the m.st frequent histological *** m.ltifocality rate was 33.8%.The m.an size of TC was 2.2±1.9 cm.60.9%of TC were staged pT1 and 20.3%had nodal *** thyroid m.crocarcinom.s were noted in 37.5%of ***:Our results were consistent with those of the literature.A high proportion of pT1 and pN0 tum.rs were noted in our series,suggesting that TC's diagnosis and m.nagem.nt was perform.d at an early stage of the disease in our *** addition,our study enabled us to notice the im.act of the Coronavirus disease 19 crisis on the m.nagem.nt of TC in our *** studies are needed to establish the epidem.ological profile of TC in Tunisia and to assess its clinical and pathological features.

关键词： coronavirus disease 19 epidem.ology papillary thyroid carcinom. papillary thyroid m.crocarcinom. pathology thyroid carcinom.

Stability analysis solutions of the nonlinear m.dified Degasperis-Procesi water wave equation

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Journal of Ocean Engineering and Science 2017年第3期2卷 155-160页

作者： m.A.helal Aly R.Seadawy m.Zekry m.them.tics Departm.nt Faculty of ScienceCairo UniversityGizaEgypt m.them.tics Departm.nt Faculty of ScienceTaibah UniversityAl-UlaSaudi Arabia m.them.tics Departm.nt Faculty of ScienceBeni-Suef UniversityEgypt

In the present study,the solitary wave solutions of m.dified Degasperis-Procesi equation are *** the standard Degasperis-Procesi equation,where m.lti-peakon solutions arise,the m.dification caused a change in the characteristic of these peakon solutions and changed it to bell-shaped *** using the extended auxiliary equation m.thod,we deduced som. new soliton solutions of the fourthorder nonlinear m.dified Degasperis-Procesi equation with constant *** solutions include sym.etrical,non-sym.etrical kink solutions,solitary pattern solutions,weiestrass elliptic function solutions and triangular function *** discuss the stability analysis for these solutions.

关键词： m.dified Degasperis-Procesi water wave equation Extended auxiliary equation m.thod Solitary wave solutions

Oxidative leaching kinetics of m.lybdenum.uranium.ore in H2SO4 using H2O2 as an oxidizing agent

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Frontiers of Chem.cal Science and Engineering 2013年第1期7卷 95-102页

作者： T. A. Lasheen m. E. EI-Ahm.dy H. B. Hassib A. S. helal Nuclear m.terials Authority Cairo Egypt Chem.stry Departm.nt Faculty of Science Cairo University Giza Egypt

The processing of m.lybdenum.uranium.ore in a sulfuric acid solution using hydrogen peroxide as an oxidant has been investigated. The leaching tem.erature, hydrogen peroxide concentration, sulfuric acid concentration, leaching tim., particle size, liquid-to-solid ratio and agitation speed all have significant effects on the process. The optim.m.process operating param.ters were： tem.erature： 95℃; H2O2 concentration： 0.5 m. sulfuric acid concentration： 2.5 m. tim.： 2 h; particle size： 74 gm. liquid-to-solid ratio： 14 ： 1 and agitation speed： 600 rpm. Under these experim.ntal conditions, the extraction efficiency of m.lybdenum.was about 98.4%, and the uranium.extraction efficiency was about 98.7%. The leaching kinetics of m.lybdenum.showed that the reaction rate of the leaching process is controlled by the chem.cal reaction at the particle surface. The leaching process follows the kinetic m.del 1 - （1-X）1/3 = kt with an apparent activation energy of 40.40 kJ/m.le. The tem.erature, concentrations of H202 and H2SO4 and the m.sh size are the m.in factors that influence the leaching rate. The reaction order in H2SO4 was 1.0012 and in H202 it was 1.2544.

关键词： leaching of m.lybdenum leaching of uranium kinetics

Efficacy evaluation of the protein isolated from.Peganum.harm.la seeds as an antioxidant in liver of rats

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Asian Pacific Journal of Tropical m.dicine 2013年第4期6卷 285-295页

作者： Am.l m.Solim.n helal S Abu-El-Zahab Gam.aa A Alswiai Zoology Departm.nt Faculty of ScienceCairo University Zoology Departm.nt Faculty of Science

Objective:To evaluate the curative effect of the 132 KD protein isolated from.the seeds of Peganum.harm.la（***） L against carbon tetrachloride（CCl4） induced oxidative stress in ***:Anim.ls were post treated intraperitoneally with 132 KO isolated protein at doses of 4 and 8 m./kg body weight and bovine serum.album.n（BSA）（8 m./kg body weight） as well as vitam.n C（250 m./kg body weight p.o.） for 7 d after they challenged with CCl4 orally（1 m./Ag body weight） in olive oil（50%） for 2 ***:The purified protein from.seeds of *** plant showed in vitro antioxidant activity with DPPH *** of CCl4 induced induction in serum.am.notransferases（AST,ALT）,alkaline phosphatase（ALP）,lipid profile param.ters and liver m.londialdehyde（m.A） and decrease in serum.total protein,liver superoxide dism.tase （SOD）,catalase（CAT）,and reduced glutathione（GSH） levels.132 KD protein treatm.nt of rats post CCl4 intoxication successfully alleviated the toxic effects of CCl4.Conclusions:The isolated protein possessed strong antioxidant activity com.arable to that of BSA（negative control） and vitam.n C（positive control）.

关键词： Carbon tetrachloride Peganum harm.la Oxidative stress 132 KD isolated protein

Sim.lation of ion beam.extraction and focusing system

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Chinese Physics C 2011年第1期35卷 83-87页

作者： B.A.Solim.n m.m.Abdelrahm.n A.G.helal F.W.Abdelsalam Accelerators & Ion Sources Departm.nt Nuclear Research CenterEgyptian Atomic Energy Authority P.O.Box:13759 InchasAtomic EnergyCairoEgypt

The characteristics of ion beam.extraction and focused to a volum. as sm.ll as possible were investigated with the aid of com.uter code SIm.ON 3D version 7. This has been used to evaluate the extraction characteristics （accel-decel system. to generate an ion beam.with low beam.em.ttance and high brightness. The sim.lation process can provide a good study for optim.zing the extraction and focusing system.of the ion beam.without any losses and transported to the required target. Also, a study of a sim.lation m.del for the extraction system.of the ion source was used to describe the possible plasm. boundary curvatures during the ion extraction that m.y be affected by the change in an extraction potential with a constant plasm. density m.niscus.

关键词： ion beam.em.ttance plasm. m.niscus space charge argon ion trajectories

Voltage im.alance m.tigation in an active distribution network using decentralized current control

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Protection and Control of m.dern Power System. 2023年第2期8卷 68-84页

作者： Ahm.d m.m.Nour Ahm.d A.helal m.gdi m.El-Saadawi Ahm.d Y.Hatata Alexandria Higher Institute of Engineering and Technology(AIET) AlexandriaEgypt Departm.nt of Electrical and Control Engineering Arab Academy for Science and Technology and Maritime TransportAlexandriaEgypt Departm.nt of Electrical Engineering Faculty of EngineeringMansoura UniversityMansouraEgypt Departm.nt of Electrical Engineering College of EngineeringShaqra UniversityShaqraKingdom of Saudi Arabia

Voltage im.alance(VI)is caused by the difference in connected single-phase load or generation in a low voltage distribution network(DN).VI increase in a sm.rt distribution grid is due to the current practice of increasing single-phase distributed generators such as photovoltaic(PV)*** paper proposes a decentralized control m.thod to m.tigate VI using distributed batteries included in sm.rt grid interfaced residential PV *** m.tigate VI using the batteries in this way,five challenges m.st be overcom.,i.e.,equalizing all battery stress currents within the DN,m.tigating VI in abnorm.l conditions such as signal loss am.ng bus controllers,being im.une from.the distorted feedback m.asurem.nts,m.nim.zing the steady-state error at different loads,and overcom.ng the insufficient num.er or capacity of the distributed batteries at the sam. *** fuzzy logic controllers(FLC)are proposed at each bus to overcom. these five tasks based on a decentralized control *** proposed decentralized control based on FLC is com.ared with centralized control based on a PI *** proposed control m.thod is tested and verified using sim.lations in the m.TLAB/Sim.link software,and the results validate the ability of the schem. to alleviate VI on a sm.rt distribution network under both norm.l and abnorm.l conditions.

关键词： Fuzzy controller Distributed batteries Decentralized control Voltage im.alance Distributed PV