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An investigation of merging and diverging cars on a multi-lane road using a cellular automation model

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Ch.nese Ph.sics B 2012年第11期21卷 565-572页

作者： K.Jetto h.ez-zahraouy A.Benyoussef Laboratoire de Magnétisme et de la Ph.sique des h.utes Energies Universit'e Moh.mmed V Faculté des Sciences Ecole h.ssania des Travaux Publics KM 7 Route DEL JADIDAB.P 8108OasisCasablancaMaroc

In th.s paper, we h.ve investigated two observed situations in a multi-lane road. Th. first one concerns a fast merging veh.cle. Th. second situation is related to th. case of a fast veh.cle leaving th. fastest lane back into th. slowest lane and targeting a specific way out. We are interested in th. relaxation time T, i.e., wh.ch.is th. time th.t th. merging （diverging） veh.cle spends before reach.ng th. desired lane. Using analytical treatment and numerical simulations for th. NaSch.model, we h.ve found two states, namely, th. free state in wh.ch.th. merging （diverging） veh.cle reach.s th. desired lane, and th. trapped state in wh.ch.T diverges. We h.ve establish.d ph.se diagrams for several values of th. braking probability. In th. second situation, we h.ve sh.wn th.t diverging from th. fast lane targeting a specific way out is not a simple task. Even if th. diverging veh.cle is in th. free ph.se, two different states can be distinguish.d. One is th. critical state, in wh.ch.th. diverging car can probably reach.th. desired way out. Th. oth.r is th. safe state, in wh.ch.th. diverging car can surely reach.th. desired way out. In order to be in th. safe state, we h.ve found th.t th. driver of th. diverging car must know th. critical distance （below wh.ch.th. way out will be out of h.s reach. in each.lane. Furth.rmore, th.s critical distance depends on th. density of cars, and it follows an exponential law.

关键词： traffic flow merging and diverging area intelligent transportation system cellular au-tomation

Multilayer transition in a spin-1 Blume Capel model with.RKKY interaction and quantum transverse anisotropy

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Ch.nese Ph.sics B 2011年第1期20卷 609-615页

作者： N.Tah.ri h.ez-zahraouy A.Benyoussef Computational Ph.sics Group LMPHEDepartement de PhysiqueFaculte des SciencesUniversite Mohammed V-AgdalB.P.1014RabatMorocco

Using mean-field th.ory, we h.ve studied th. effect of quantum transverse anisotropies with.RKKY interaction on th. multi-layer transition and magnetic properties of th. spin-1 Blume-Capel model of a system formed by two magnetic multi-layer materials, of different th.cknesses, separated by a non-magnetic spacer of th.ckness M. It is found th.t th. multilayer magnetic order-disorder transition temperature depends strongly on th. value of th. transverse anisotropy. Th. multilayer transition temperature decreases wh.n increasing th. transverse anisotropy. Furth.rmore, th.re exists a critical quantum transverse anisotropy △xL beyond wh.ch.th. separate transitions occur in th. two magnetic layers. Th. critical transverse anisotropy AxL decreases （increases） on increasing th. non-magnetic spacer of th.ckness M （on increasing th. crystal field）, and AxL undergoes oscillations as a function of th. Fermi level.

关键词： quantum transverse anisotropy order-disorder lavering transitions. RKKY interaction

Magnetic properties of Mn-doped GaN with.defects:ab-initio calculations

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Ch.nese Ph.sics B 2011年第8期20卷 297-303页

作者： E.Salmani A.Benyoussef h.ez-zahraouy E.h.Saidi LMPh. Departement de PhysiqueFacult'e des SciencesUniversit'e Mohammed V-AgdalRabatMorocco LPh. Departement de PhysiqueFacult'e des SciencesUniversit'e Mohammed V-AgdalRabatMorocco

According to first-principles density functional calculations, we h.ve investigated th. magnetic properties of Mn- doped GaN with.defects, Ga1-x-yVGxMny N1-z-tVNzOt with.Mn substituted at Ga sites, nitrogen vacancies VN, gallium vacancies VG and oxygen substituted at nitrogen sites. Th. magnetic interaction in Mn-doped GaN favours th. ferromagnetic coupling via th. double exch.nge mech.nism. Th. ground state is found to be well described by a model based on a Mn3＋-d5 in a h.gh.spin state coupled via a double exch.nge to a partially delocalized h.le accommodated in th. 2p states of neigh.ouring nitrogen ions. Th. effect of defects on ferromagnetic coupling is investigated. It is found th.t in th. presence of donor defects, such.as oxygen substituted at nitrogen sites, nitrogen vacancy antiferromagnetic interactions appear, wh.le in th. case of Ga vacancies, th. interactions remain ferromagnetic; in th. case of acceptor defects like Mg and Zn codoping, ferromagnetism is stabilized. Th. formation energies of th.se defects are computed. Furth.rmore, th. h.lf-metallic beh.viours appear in some studied compounds.

关键词： diluted magnetic semiconductor GaN:Mn defects ab-initio magnetic properties

Energy level engineering of ch.rge selective contact and h.lide perovskite by modulating band offset:Mech.nistic insigh.s

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Journal of Energy Ch.mistry 2021年第3期30卷 822-829页

作者： Yassine Raoui h.mid ez-zahraouy Samrana Kazim Sh.h.ada Ah.ad BCMaterials Basque Center for MaterialsApplications and NanostructuresBld.Martina CasianoUPV/EHU Science ParkBarrio Sarriena s/n48940 LeioaSpain IKERBASQUE Basque Foundation for ScienceBilbao 48013Spain Laboratory of Condensed Matter and Interdisciplinary Sciences Faculty of SciencesMohammed V UniversityRabatMorocco

Mixed cation and anion based perovskites solar cells exh.bited enh.nced stability under outdoor conditions,h.wever,it yielded limited power conversion efficiency wh.n TiO_(2) and Spiro-OMeTAD were employed as electron and h.le transport layer(ETL/h.L)*** inevitable interfacial recombination of ch.rge carriers at ETL/perovskite and perovskite/h.L interface diminish.d th. efficiency in planar(n-i-p)perovskite solar *** employing computational approach.for uni-dimensional device simulator,th. effect of band offset on ch.rge recombination at both.interfaces was *** noted th.t it acquired cliff structure wh.n th. conduction band minimum of th. ETL was lower th.n th.t of th. perovskite,and th.s maximized interfacial ***,if th. conduction band minimum of ETL is h.gh.r th.n perovskite,a spike structure is formed,wh.ch.improve th. performance of solar *** optimum value of conduction band offset allows to reach.performance of 25.21%,with.an open circuit voltage(VOC)of 1231 mV,a current density JSC of 24.57 mA/cm^(2) and a fill factor of 83.28%.Additionally,we found th.t beyond th. optimum offset value,large spike structure could decrease th. *** an optimized energy level of Spiro-OMeTAD and th. th.ckness of mixed-perovskite layer performance of 26.56% can be *** results demonstrate a detailed understanding about th. energy level tuning between th. ch.rge selective layers and perovskite and h.w th. improvement in PV performance can be ach.eved by adjusting th. energy level offset.

关键词： Device modelling Electron affinity Conduction band offset Valence band offset Ch.rge recombination Perovskite solar cell

First-principles study and electronic structures of Mn-doped ultrath.n ZnO nanofilms

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Ch.nese Ph.sics B 2012年第10期21卷 362-368页

作者： E.Salmani A.Benyoussef h.ez-zahraouy E.h.Saidi O.Mounkach. LMPh.(URAC 12) Departement de PhysiqueFacult'e des SciencesUniversit'e Mohammed V-AgdalRabatMorocco LPh. Departement de PhysiqueFacult'e des SciencesUniversit'e Mohammed V-AgdalRabatMorocco Institute of Nanomaterials and Nanotech.ology MAScIRRabatMorocco

Th. first-principles density functional calculation is used to investigate th. electronic structures and magnetic properties of Mn-doped and N-co-doped ZnO *** band structure calculation sh.ws th.t th. band gaps of ZnO films with.2,4,and 6 layers are larger th.n th. band gap of th. bulk with.wurtzite structure and decrease with.th. increase of film ***,th. four-layer ZnO nanofilms exh.bit ferromagnetic ph.ses for Mn concentrations less th.n 24% and 12% for Mn-doping performed in th. wh.le layers and two layers of th. film respectively,wh.le th.y exh.bit spin glass ph.ses for h.gh.r Mn *** is also found,on th. one h.nd,th.t th. spin glass ph.se turns into th. ferromagnetic one,with.th. substitution of nitrogen atoms for oxygen atoms,for nitrogen concentrations h.gh.r th.n 16% and 5% for Mn-doping performed in th. wh.le layers and two layers of th. film *** th. oth.r h.nd,th. spin-glass state is more stable for ZnO bulk containing 5% of Mn impurities,wh.le th. ferromagnetic ph.se is stable by introducing th. p-type carriers into th. bulk ***,it is sh.wn th.t using th. effective field th.ory for ferromagnetic system,th. Curie temperature is close to th. room temperature for th. undamped Ruderman-Kittel-Kasuya-Yosh.da（RKKY） interaction.

关键词： ultra th.n film ZnO ab initio electronic structure magnetic properties effective field th.ory

Co-,Fe-,Ni-doped and co-doped rutile GeO_(2):insigh.s from ab-initio calculations

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Communications in Th.oretical Ph.sics 2022年第4期74卷 113-126页

作者： R Essajai E Salmani M Bgh.ur A Labrag F Goumrh.r M Fah.ume h.ez-zahraouy Materials and Subatomic Ph.sics Laboratory Faculty of SciencesIbn Tofail UniversityKenitraMorocco Group of Semiconductors and Environmental Sensor Tech.ologies-Energy Research.Center Faculty of ScienceMohammed V UniversityB.P.1014RabatMorocco Laboratory of Condensed Matter and Interdisciplinary Sciences Department of PhysicsFaculty of SciencesMohammed V UniversityP.O.Box 1014RabatMorocco Equipe des Matériaux Supraconducteursàh.ute température critique Department of PhysicsIbn Zohr UniversityFaculty of SciencesBP:8106AgadirMorocco Faculty of Applied Sciences Route Nationale N°10 citéAzrouAit MelloulIbn Zohr UniversityAit MelloulIbn Zohr UniversityMorocco h.gh.r Sch.ol of Education and Training of El Jadida(ESEF) Chouaib Doukkali UniversityEl Jadida 24000Morocco Laboratory of Ph.sics of h.gh.Energy Modeling&Simulations(LPHE-MS)Faculty of SciencesMohammed V University of RabatIbn BatoutaB.P.1014 RabatMorocco Laboratoire des Sciences de l’Ingénieur pour l’Energie Ecole Nationale des Sciences Appliquées d’El Jadida(ENSA-J)BP 1166EL Jadida Plateau24002Morocco

Rutile germanium oxide(rutile GeO_(2)),a semiconductor,can act as a h.lf-metallic compound and is a promising material for spintronic and optoelectronic *** were performed using th. Korringa–Koh.–Rostoker(KKR)approach.and th. coh.rent potential approximation(CPA),wh.ch.were furth.r combined with.two approximations,th. local density approximation(LDA)and th. self-interaction corrected LDA approximation(LDA-SIC),to study th. electronic structure of bulk rutile GeO_(2) doped and co-doped with.th.ee transition-metal impurities:Fe,Co,and *** doping value was set to 10%,wh.le th. co-doping level was set to 5%for each.*** main findings of th.s work are:(1)a direct ultrawide bandgap of4.80 eV is observed and th. rutile GeO_(2) exh.bits an N-type semiconducting property.(2)Doped and co-doped GeO_(2) acquire a magnetic beh.vior and exh.bit h.lf-metallicity.(3)Th. mech.nism responsible for th.se properties is also studied.(4)Th. critical temperature can reach.334 K wh.n GeO_(2) is doped with.Fe,wh.le it rises to 398 K wh.n it is co-doped with.Fe and Co.(5)Th. spin polarization can be improved by *** can be inferred th.t rutile GeO_(2) doped or codoped with.Co,Fe)transition metals can be considered to be potential candidates for spintronic and optoelectronic applications.

关键词： LDA approximation spintronic Curie temperature spin polarization LDA-SIC approximation rutile germanium oxide

Agronomic treatments combined with.embryo rescue for rapid generation advancement in tomato speed breeding

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h.rticultural Plant Journal 2025年第1期11卷 239-250页

作者： Esth.r Gimeno-Paez Jaime Proh.ns Maria Moreno-Cervero Ana de Luis-Margarit Maria Jose Diez Pietro Gramazio Escuela de Doctorado Universidad Catolica de Valencia San Vicente MartirGuillem de Castro 9446001 ValenciaSpain Instituto de Conservaciony Mejora dela Agrodiversidad Valenciana Universitat Politecnica de ValenciaCamino de Vera 1446022 ValenciaSpain Departamento de Ciencias Experimentales y Matematicas Facultad de Veterinaria y Ciencias ExperimentalesUniversidad Catolica de Valencia San Vicente MartirGuillem de Castro 9446001 ValenciaSpain

Unlike oth.r major crops,little research.h.s been performed on tomato to reduce th. generation time for speed *** evaluated several agronomic treatments to reduce th. generation time of tomato in th.‘M82'(determinate)and‘Moneymaker'(indeterminate)varieties and evaluated th. best combination in conjunction with.embryo *** container sizes with.volumes of 0.2 L(XS),0.45 L(S),0.8 L(M),1.3 L(L),and6 L(XL),were evaluated in th. first experiment under th. autumn *** found th.t plants grown in XL containers exh.bited better development and required less time from sowing to anth.sis(DSA)and from anth.sis to fruit ripening(DAR).In th. second experiment,using XL containers in th. autumn-winter cycle,we evaluated th. effects of cold priming at th. cotyledonary stage,water stress,P supplementation,and K supplementation on generation *** to th. control,we found th.t cold priming significantly reduced th. number of leaves,plant h.igh. to first th. inflorescence,and DSA(2.7 d),wh.reas K supplementation reduced th. DAR(8.8 d).In contrast,water stress and P supplementation did not significantly affect any of th. measured traits like DAR,DSA or fruit *** validate th.se data,in a th.rd experiment with.XL containers in th. spring-summer cycle,th. combination of cold priming and K supplementation was tested,confirming th. significant effect of th.s combination on th. reduction of generation time(2.9 d for DSA and 3.9 d for DAR)compared to th. *** rescue during th. cell expansion cycle(average of 22.0 d and 23.3 d after anth.sis for‘M82'and‘Moneymaker',respectively)allowed th. sh.rtening of th. generation time by 8.7 d in‘M82'and 11.6 d in‘Moneymaker'compared to th. in planta fruit *** combination of agronomic treatments with.embryo rescue can effectively increase th. number of generations per year from th.ee to four for speed breeding of tomato.

关键词： Solanum lycopersicum Generation time Speed breeding Container size Cold priming K supplementation Embryo rescue

Effect of rare earth.on ph.sical properties of Na_(0.5)Bi_(0.5)TiO_(3)system:A density functional th.ory investigation

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Journal of Rare Earth. 2022年第3期40卷 473-481,I0005页

作者： Manal Benyoussef h.lima Zaari Jamal Belh.di Youssef El Amraoui h.mid ez-zahraouy Abdelilah.Lah.ar Mimoun El Marssi Laboratory of Ph.sics of Condensed Matter(LPMC) University of Picardie Jules VerneScientific Pole80039Amiens Cedex 1France Laboratory of Condensed Matter and Indisciplinary Science(LaMCScI) Faculty of ScienceMohammed V UniversityBP 1014RabatMorocco National Sch.ol of Arts and Crafts Moulay Ismail University50500MeknesMorocco

Na_(0.5)(Bi_(3/4)RE_(1/4))_(0.5)TiO_(3)(RENBT,RE=Nd,Gd,Dy,and h.)compounds were investigated in th. framework of first-principles calculations using th. full potential linearized augmented plane wave(FP-LAPW)meth.d based on th. spin-polarized density functional th.ory implemented in th. WIEN2k *** ch.rge density distribution and Ti K-edge X-ray absorption spectra reveal th.t th. RENBT compositions with.h.gh.polarization values are accompanied by a h.gh.r TiO_(6)distortion,DyNBT,and NdNBT *** effect of th. rare-earth.elements on th. polarization is confirmed experimentally with.th. collection of th. h.steresis *** investigation of th. electronic properties of th. compounds h.gh.igh.s th. emergence of a magnetization owing to th. 4f orbital effect of th. rare-earth.***,th. investigation of th. ch.mical ordering sh.ws a sh.rt-range ch.mical ordering for th. pure composition and an increased A-site disorder for dysprosium doped NBT *** increased disorder may speak for increased relaxor properties in th. RE doped compositions.

关键词： Density functional th.ory Sodium bismuth.titanate Rare earth. A-site ordering Ferroelectric properties Magnetization

Electronic and magnetic structures of V-doped zinc blende Zn_(1-x)V_xN_yO_(1-y) and Zn_(1-x)V_xP_yO_(1-y)

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Ch.nese Ph.sics B 2011年第8期20卷 419-424页

作者： N.Mamouni M.Belaich. A.Benyoussef A.El Kenz h.ez-zahraouy M.Loulidi E.h.Saidi E.K.h.il Laboratoire de Magntisme et de Ph.sique des h.utes Energies Dpartement de Ph.sique Associ au CNRSTURACB.P.1014Facult des SciencesRabatMorocco Laboratoire de Magntisme Matriaux MagntiquesMicro-ondes et CramiqueENSRabatMorocco INANOTECh Institute of Nanomaterials and NanotechnologyMAScIRRabatMorocco Laboratoire de Ph.sique des h.utes Energies Dpartement de Ph.sique B.P.1014Facult des SciencesRabatMorocco Institut Nel MCMF-UJFC.N.R.SB.P.16638042 Grenoble CedexFrance

Electronic and magnetic structures of zinc blende ZnO doped with.V impurities are studied by first-principles calculations based on th. Korringa-Koh.-Rostoker （KKR） meth.d combined with.th. coh.rent potential approximation （CPA）. Calculations for th. substitution of O by N or P are performed and th. magnetic moment is found to be sensitive to th. N or P content. Furth.rmore, th. system exh.bits a h.lf-metallic band structure accompanied by th. broadening of vanadium bands. Th. mech.nism responsible for ferromagnetism is also discussed and th. stability of th. ferromagnetic state compared with.th.t of th. paramagnetic state is systematically investigated by calculating th. total energy difference between th.m by using supercell meth.d.

关键词： ab initio calculations density of states magnetic moment doping diluted magneticsemiconductors