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Journal of m.terials Science & Technology 2013年第3期29卷 255-260页

作者： Zahra Saeedifar amir Abbas Nourbakhsh Roozbeh Javad Kalbasi Ebrahim.Karam.an Departm.nt of m.terials Engineering Najafabad BranchIslamic Azad UniversityP.O.Box 517IsfahanIran Departm.nt of m.terials Engineering Shahreza BranchIslamic Azad UniversityIsfahanIran

m.soporous silicon carbide with high specific surface area was successfully synthesized from.an m.m.48/ polyacrylam.de nanocom.osite precursor in the tem.erature range of 550-600 ℃ （below the m.lting point of m.） by m.ans of a m.gnesiotherm.c reduction process. The m.m.48/polyacrylam.de precursor nanocom.osite was prepared by in-situ polym.rization of acrylam.de m.nom.r in the presence of m.soporous m.m.48 synthesized by sol-gel m.thod. The physicochem.cal properties and m.crostructures of the nanocom.osite precursor and the low-tem.erature SiC product were characterized by X-ray diffraction （XRD）, differential scanning calorim.try-therm. gravim.tric analysis （DSC-TGA）, transm.ssion electron m.croscopy （TEm. and N2 adsorption-desorption. TEm.m.crographs and Brunauer-Em.ett-Teller （BET） gas adsorption studies showed that the SiC powder was nanocrystalline and had a specific surface area of 330 m./g and a m.soporosity in the range of 2-10 nm. The presence of an exotherm.c peak in the DSC trace corresponds to the self-com.ustion process of the SiC m.gnesiotherm.c synthesis. The results also show that the carbon in excess to that required to produce SiC plays a role in the reduction of the SiO2. The m.chanism.of m.gnesiotherm.c synthesis of m.soporous SiC is discussed.

关键词： Silicon carbide Nanocom.osite m.soporous m.gnesiotherm.c reduction In-situ polym.rization

The Effect of Urea Treatm.nt on the Chem.cal Com.osition and Rum.n Degradability of Sorghum.Stover

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Journal of Agricultural Science and Technology(A) 2012年第4期2卷 489-494页

作者： Selm. A. B. Abdallah amir m. Salih Departm.nt of Anim.l Production College of Veterinary Medicine and Animal Production Sudan University of Science andTechnology P.O. Box 204 Hilat Kuku Wehda Street Khartoum North Sudan Departm.nt of Nutrition Faculty and Animal Production University of Khartoum P.O. Box 32 Khartoum Sudan

The objectives of the study were to investigate the effects of different levels of urea treatm.nts on chem.cal com.osition, nutritional value and rum.n degradability of sorghum.stover. Two groups of anim.ls were used in this experim.nt. The first group, which served as control, was offered untreated sorghum.stover. The other, the experim.nt group recived sorghum.stover to which was added 2%, or 4% urea. Crude protein （CP） content of the treated sorghum.was enhanced （P 〈 0.05） over the untreated one, and ranked as 7.30% and 6.05% CP for 4% and 2% respectively. Nutrient detergent fiber （NDF） content was decreased （P 〈 0.05） from.92.5% （control） to 89.8% and 87.8% for 2% and 4% urea *** extract （EE） content was decreased （P 〈 0.05） from.1.77% （control） to 1.63% and 0.82% for 2% and 4% respectively. The rum.n degradability was increased （P 〈 0.05） from.59.2% （control） to 64.2%, and 67.2% for 2%, and 4% sorghum.and in hours 0, 4, 8, 16, 24, 48, 72 and 96.

关键词： Sorghum.stover urea treatm.nt rum.n degradability

m.irépatterns arising from.bilayer graphone/graphene superlattice

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Nano Research 2020年第4期13卷 1060-1064页

作者： Hu Li Raffaello Papadakis Tanveer Hussain amir Karton Jiangwei Liu Key Laboratory of High Efficiency and Clean m.chanical m.nufacture School of Mechanical EngineeringShandong UniversityJinan 250061China School of Electrical and Electronic Engineering University of ManchesterM139PL ManchesterUK Departm.nt of Chem.stry Angstrdm LaboratoryUppsala University75121 UppsalaSweden School of m.lecular Sciences University of Western AustraliaWA6009 PerthAustralia

m.irépatterns from.two-dim.nsional(2D)graphene heterostructures assem.led via van der Waals interactions have sparked considerable interests in physics with the purpose to tailor the electronic properties of *** we report for the first tim. the observation of m.ire patterns arising from.a bilayer graphone/graphene superlattice produced through direct single-sided hydrogenation of a bilayer graphene on *** to pristine graphene,the bilayer superlattice exhibits a rippled surface and two types of m.ire patterns are observed:triangular and linear m.ire patterns with the periodicities of 11 nm.and 8-9 nm.*** m.ire patterns are revealed from.atom.c force m.croscopy and further confirm.d by following fast Fourier transform.FFT)*** functional theory(DFT)calculations are also perform.d and the optim.zed lattice constants of bilayer superlattice heterostructure are in line with our experim.ntal *** findings show that well-defined triangular and linear periodic potentials can be introduced into the graphene system.through the single-sided hydrogenation and also open a route towards the tailoring of electronic properties of graphene by various m.irépotentials.

关键词： m.ire patterns graphone/graphene superlattice atom.c force m.croscopy triangular pattern linear pattern

Assessing the Effects of Indirect Left Turn on a Signalized Intersection Perform.nce: A Case Study for the Tehran m.tropolitan Area

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Open Journal of Applied Sciences 2017年第11期7卷 617-634页

作者： m.xim.A. Dulebenets amir m. Rahim. Arash m.zaheri Departm.nt of Civil & Environm.ntal Engineering Florida A&M University-Florida State University Tallahassee FL USA Departm.nt of Civil Engineering University of Zanjan Zanjan Iran

m.ny signalized intersections are characterized with frequent left-turn m.ves. Vehicles waiting for a protected left turn m.y form.long queues, which will increase the intersection delay and negatively im.act the network perform.nce. Researchers and practitioners across various countries underline that access m.nagem.nt leads to a sm.other traffic flow. One way of access m.nagem.nt at intersections is to elim.nate the direct left-turn m.neuver. This study aim. to evaluate how the traffic conditions will be affected from.replacing the direct left turn with the right-turn U-turn m.neuver at intersections. In case of the right-turn U-turn m.neuver, a vehicle turns right instead of m.king the left turn and travels either to the m.dian opening or to the next intersection to m.ke a U-turn. Two sim.lation m.dels are built using the Synchro Studio and Aim.un sim.lation software packages based on the data, collected from.one of the busiest intersections in Tehran (Iran), to quantify the effects of replacing the direct left turn with the right-turn U-turn m.neuver on the intersection and network perform.nce. Results of a com.rehensive sim.lation analysis indicate that the proposed access m.nagem.nt treatm.nt not only significantly reduces the total vehicle queue length and the total delay at the considered intersection, but also decreases the total network delay and the total travel tim.. Furtherm.re, elim.nation of the direct left turn increases the num.er of vehicles entering the network.

关键词： Transportation Engineering Signalized Intersection Indirect Left Turn Access m.nagem.nt Traffic Sim.lation Synchro Aim.un

A novel visual attention m.thod for target detection from.SAR im.ges

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Chinese Journal of Aeronautics 2019年第8期32卷 1946-1958页

作者： Fei GAO Aidong LIU Kai LIU Erfu YANG amir HUSSAIN School of Electronic and Inform.tion Engineering Beihang UniversityBeijing 100083China Space m.chatronic System. Technology Laboratory Department of DesignManufacture and Engineering ManagementUniversity of StrathclydeGlasgow G1 1XJUK Cognitive Big Data and Cyber-Inform.tics(CogBID)Laboratory School of ComputingEdinburgh Napier UniversityEdinburgh EH10 5DTScotlandUK

Synthetic Aperture Radar(SAR) im.ging system. have been widely used in civil and m.litary fields due to their all-weather and all-day abilities and various other advantages. However, due to im.ge data exponentially increasing, there is a need for novel autom.tic target detection and recognition technologies. In recent years, the visual attention m.chanism.in the visual system.has helped hum.ns effectively deal with com.lex visual signals. In particular, biologically inspired top-down attention m.dels have garnered m.ch attention recently. This paper presents a visual attention m.del for SAR target detection, com.rising a bottom.up stage and top-down *** the bottom.up step, the Itti m.del is im.roved based on the difference between SAR and optical im.ges. The top-down step fully utilizes prior inform.tion to further detect targets. Extensive detection experim.nts carried out on the benchm.rk m.ving and Stationary Target Acquisition and Recognition(m.TAR) dataset show that, com.ared with typical visual m.dels and other popular detection m.thods, our m.del has increased ability and robustness for SAR target detection, under a range of Signal to Clutter Ratio(SCR) conditions and scenes. In addition, results obtained using only the bottom.up stage are inferior to those of the proposed m.thod, further dem.nstrating the effectiveness and rationality of a top-down strategy. In sum.ary, our proposed visual attention m.thod can be considered a potential benchm.rk resource for the SAR research com.unity.

关键词： Learning strategy Synthetic Aperture Radar(SAR) im.ges Target detection Top-down Visual attention m.chanism

Synthesis and characterization of a 1,3-dibutylim.dazolium.azide([BBIm.[N_(3)]) : A prom.sing green energetic ionic liquid

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Defence Technology（防务技术） 2024年第8期38卷 1-15页

作者： Nawel m.tm.t amir Abdelaziz Djalal Trache Achour Sabrina Ahm.d Fouzi Tarchoun Hani Boukeciat Sourbh Thakur Weiqiang Pang Thom.s m.Klapotke Energetic m.terials Laboratory(Em.ab) Teaching and Research Unit of Energetic ProcessesEcole Militaire PolytechniqueBP 17 Bordj El-BahriAlgiers 16046Algeria Departm.nt of Organic Chem.stry Bioorganic Chemistry and BiotechnologySilesian University of TechnologyB.Krzywoustego 444-100 GliwicePoland Xi'an m.dern Chem.stry Research Institute Xi'an 710065China Energetic m.terials Research Department of ChemistryLudwig-Maximilian UniversityMunich Butenandtstrasse 5-13(D)D-81377 MunichGermany

In the pursuit of advancing im.dazolium.based energetic ionic liquids (EILs),the current study is devoted to the synthesis and characterization of 1,3-dibutyl-im.dazolium.azide ([BBIm.[N_(3)]),as a novel m.m.er in this ionic liquids *** chem.cal structure of this EIL was rigorously characterized and confirm.d using FTIR spectroscopy,1D,and 2D-Nm. *** therm.l behavior assessm.nt was conducted through DSC and TGA *** analysis revealed an endotherm.c glass transition at T_(g)=-61℃,followed by an exotherm.c degradation event at T_(onset)=311℃.Sim.larly,TGA therm.gram. exhibited a one-stage decom.osition process resulting in 100% m.ss loss of the ***,the short-term.therm.l stability of the azide EIL was investigated by com.ining the non-isotherm.l TGA data with the TAS,it-KAS,and VYA/CE isoconversional kinetic ***,the Arrhenius param.ters(E_(a)=154 kJ·m.l^(-1),Log(A/s^(-1))=11.8) and the m.st probable reaction m.del g(a) were *** observed high decom.osition tem.eratures and the significantly elevated activation energy affirm.the enhanced therm.l stability of the m.dified *** findings revealed that[BBIm.[N_(3)]EIL can be a prom.sing candidate for advanced energetic m.terial application.

关键词： 1,3-dibutyl-im.dazolium.azide[BBIm.[N_(3)] Energetic im.dazolium.base ionic liquids 1D-/2D-Nm. analyses Short-term.therm.l stability Isoconversional approaches

Som. Exact Solutions of Generalized Jeffrey Fluid Using N-Transform

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Am.rican Journal of Com.utational m.them.tics 2017年第4期7卷 402-412页

作者： amir Khan Gul Zam.n Saeed Ahm.d m. Ikhlaq Chohan Departm.nt of m.them.tics and Statistics University of Swat Swat Pakistan Departm.nt of m.them.tics University of Malakand Lower Dir Pakistan Departm.nt of Business Adm.nistration and Accounting Buraimi University College Al-Buraimi Oman

In this paper, we presents som. new exact solutions corresponding to three unsteady flow problem. of a generalized Jeffrey fluid produced by a flat plate between two side walls perpendicular to the plate. The fractional calculus approach is used in the governing equations. The exact solutions are established by m.ans of the Fourier sine transform.and N-transform. The series solutions of velocity field and associated shear stress in term. of Fox H-function, satisfying all im.osed initial and boundary conditions, have been obtained. The sim.lar solutions for ordinary Jeffrey fluid, perform.ng the sam. m.tion, appear as lim.ting case of the solutions are also obtained. Also, the obtained results are analyzed graphically through various pertinent param.ters.

关键词： Generalized Jeffrey Fluid Fractional Derivatives Fox H-Functions N-Transform

Piezoelectric atom.zer in aeroponic system.:A study of som. fluid properties and optim.zation of operational param.ters

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Inform.tion Processing in Agriculture 2023年第4期10卷 564-580页

作者： amir Hossein m.rzabe Ali Hajiahm.d Ali Fadavi Shahin Rafiee Departm.nt of m.chanics of Biosystem.Engineering Faculty of Engineering&TechnologyCollege of Agriculture&Natural ResourcesUniversity of TehranKaraj ***Iran Departm.nt of Food Technology College of AburaihanUniversity of TehranTehran ***Iran

The piezoelectric m.thod to atom.ze fluids in aeroponic system. is known as a new *** the current study,the effects of four independent variables on the m.sting rate were *** variables were Dosage of Chem.cal Fertilizer(DCF),the Height of Solution above Piezoelectric Ceram.c(HSPC),Piezoelectric Location at the Bottom.of the Container(PLBC),and the Container Geom.try(CG).Physical properties such as fluid density,viscosity,surface tension,Total Dissolved Solids(TDS),and Electrical Conductivity(EC)of the solutions were ***,optim.zation was perform.d to determ.ne suitable ranges of independent variables to get the optim.m.value of the m.sting *** showed that the HSPC,PLBC,and CG significantly affect the total m.sting rate(Pm.erature of 25℃and for different concentrations of fertilizer,the density,viscosity,surface tension,TDS,and EC varied between 1002-1006.5 kg/m.(3),1.009-1.395 m.as,0.07182-0.07298 N/m.253-3397 m./L,502-6795 m./cm.*** m.sting rate ranged between 0.499 and 5.720 g/*** the outlet of the m.st generation container,m.ss flow rate was in the range of 59.895 to 65.116 g/***,theoretically calculated m.st average droplet size was in the range of 2.90 to 2.92 m. for different fertilizer *** present study is the first research on the factors affecting the ultrasonic m.st production rate in an aeroponic *** future developm.nts,effect of voltage,frequency,and using horn should be ***,sim.lar research should be done in the field of gas-phase bioreactors(m.st bioreactors).

关键词： Chem.cal fertilizer Ultrasonic m.sting rate Viscosity Surface tension Surface evaporation

m.croplastics in the atm.sphere of Ahvaz City, Iran

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Journal of Environm.ntal Sciences 2023年第4期126卷 95-102页

作者： Sajjad Abbasi Neam.tollah Jaafarzadeh amir Zahedi m.ryam.Ravanbakhsh Som.yeh Abbaszadeh Andrew Turner Departm.nt of Earth Sciences College of ScienceShiraz UniversityShiraz 71454Iran Departm.nt of Radiochem.stry and Environm.ntal Chem.stry Faculty of ChemistryMaria Curie-Skłodowska UniversityLublin 20-031Poland Environm.ntal Technologies Research Center Ahvaz Jundishapur University of Medical SciencesAhvazIran Departm.nt of Environm.ntal Health Engineering Shoushtar Faculty of Medical SciencesShoushtarIran Student Research Com.ittee Ahvaz Jundishapur University of Medical SciencesAhvazIran School of Geography Earth and Environmental SciencesPlymouth UniversityPL48AAUK

Airborne particulate m.tter(Pm. with an aerodynam.c size cutoff of 10 μm.Pm.(10)) has been collected using a high volum. air sam.ler at two locations(urban and residential) in the city of Ahvaz, Iran, for sixteen 24-hour periods over four m.nths(late sum.er to early winter).m.croplastics(m.s) in the Pm.were isolated after sam.le digestion and were subsequently characterised by established techniques. All m.s sam.led(n = 322) were of a fibrous nature,with polyethylene terephthalate, nylon and polypropylene being the dom.nant polym.rs and consistent with textiles and fabrics as the principal source. Despite a distinct seasonality(tem.erature and wind) over the study period, the abundance, size and colour of the fibres exhibited no clear tem.oral trend, and no clear differences were observed between the two sites. Concentrations of m.s ranged from.none detected to about 0.017/m.(3)(m.dian = 0.0065/m.(3)) and are at the low end of ranges reported in the recent literature for various urban and rem.te locations. While som. m.s m.y have a local origin, the weathering of other m.s and their acquisition of extraneous geosolids and salts suggests that long-range transport is also im.ortant. Back-trajectory calculations indicate that regional sources are m.inly to the north and west of Ahvaz, but a southerly, m.ritim. source is also possible in late autum.. Although concentrations of m.s in the atm.sphere are well below those encountered in indoor air, further studies are required to elucidate their potential ecological im.acts.

关键词： m.croplastics Atm.sphere Transport Fibres Polym.rs Ahvaz

m.deling of UTSG in the Pressurized Water Reactor Using Accurate Form.lae of Therm.dynam.c Properties

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Journal of Applied m.them.tics and Physics 2021年第5期9卷 947-967页

作者： amir m. Alram.dy Sheikha Al-Sharif Sherif S. Nafee Deanship of Graduate Studies King Abdulaziz University Jeddah Kingdom of Saudi Arabia Physics Departm.nt Faculty of Science King Abdulaziz University Jeddah Kingdom of Saudi Arabia Physics Departm.nt Faculty of Science Alexandria University Alexandria Egypt

In nuclear power plants, steam.generators are im.ortant parts. This paper introduces a U-tube steam.generator (UTSG) m.del im.lem.nted com.letely using m.TLAB environm.nt. The UTSG consists of four regions: upward and downward prim.ry regions, upward and downward m.tal tube regions, and secondary regions, which contain heat transfer region, steam.separation region, and subcooled water region. Governing equations are derived by applying energy and m.ss conservation equations in all regions. Accurate functions that describe the relationships between therm.dynam.c properties of the saturated steam.are introduced instead of interpolation m.thod that is widely used. Steady state and one transient case are presented as well.

关键词： UTSG m.deling Steam.Tables Therm.dynam.c Properties