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Journal of System. Science & Com.lexity 2024年第1期37卷 136-151页

作者： PAN Zini CHEN Ben m Departm.nt of m.chanical and Autom.tion Engineering The Chinese University of Hong KongHong KongChina

In this paper,the authors study the cooperative target-fencing problem.for n-dim.nsional system. and a target with a general trajectory.Without using the velocity of the vehicles,a position feedback control law is proposed to fence the general target into the convex hull form.d by the vehicles.Specifically,the dynam.cs of each vehicle is described by a double-integrator system.Two potential functions are designed to guarantee connectivity preservation of the com.unication network and collision avoidance am.ng the vehicles.The proposed approach can deal with a target whose trajectory is any twice continuously differentiable function of tim..The effectiveness of the result is verified by a num.rical exam.le.

关键词： m.lti-agent system. networked system. target fencing

Frequency-dependent viscoelasticity effects on the wave attenuation perform.nce of m.lti-layered periodic foundations

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Applied m.them.tics and m.chanics(English Edition) 2024年第3期45卷 407-424页

作者： m.SAFI m.VAKILIFARD m.J.m.Hm.ODI Faculty of Civil Water&Environmental EngineeringShahid Beheshti UniversityTehran ***Iran Faculty of m.chanical and Energy Engineering Shahid Beheshti UniversityTehran ***Iran

In this paper,layered periodic foundations(LPFs)are num.rically exam.ned for their responses to longitudinal and transverse m.des in the tim. and frequency dom.ins.Three different unit-cells,i.e.,2-layer,4-layer,and 6-layer unit-cells,com.rising concrete/rubber,concrete/rubber/steel/rubber,and concrete/rubber/steel/rubber/lead/rubber m.terials,respectively,are taken into account.Also,the viscoelasticity behavior of the rubber is m.deled with two factors,i.e.,a frequency-independent(FI)loss factor and a linear frequency-dependent(FD)loss factor.Following the extraction of the com.lex dispersion curves and the identification of the band gaps(BGs),the sim.lations of wave transm.ssion in the tim. and frequency dom.ins are perform.d using the COm.OL software.Subsequent param.tric studies evaluate the effects of the rubber viscoelasticity m.dels on the dispersion curves and the wave transm.ssion for the longitudinal and transverse m.des.The results show that considering the rubber viscoelasticity enhances the wave attenuation perform.nce.m.reover,the transverse-m.de dam.ing is m.re sensitive to the viscoelasticity m.del than its longitudinal counterpart.The 6-layer unit-cell LPF exhibits the lowest BG,ranging from.4.8 Hz to 6.5 Hz.

关键词： layered m.tam.terial periodic foundation com.lex dispersion curve wave transm.ssion diagram

Engineering of efficient visible light photocatalysts:Ti_(1-x+y)Cu_(x)La_(y)O_(2)(x=0.03;y=0,0.005,0.01) com.ositions

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Journal of Rare Earths 2024年第3期42卷 497-505,I0003页

作者： S.m.Yakout A.m.Youssef Inorganic Chem.stry Departm.nt National Research Centre(NRC)El Buhouth StDokkiCairo12622Egypt

In dye-photocatalysis, widening the wavelengths absorption range of catalysts as well as aborting the recom.ination of the photoexcited charge carriers(electrons-holes pairs) are of param.unt significance.In the current study, we report the photocatalytic characteristics of four com.ositions com.osed of TiO_(2),Ti_(0.97)Cu_(0.03)O_(2), Ti_(0.965)Cu_(0.03)La_(0.005)O_(2)and Ti_(0.96)Cu_(0.03)La_(0.01)O_(2)powders for two harm.ul dyes(Congo red and m.thylene blue). The X-ray diffraction technique verified the configuration of m.xed anatase and rutile phases in pure TiO_(2)and Ti_(0.97)Cu_(0.03)O_(2)powders while Ti_(0.965)Cu_(0.03)La_(0.005)O_(2)and Ti_(0.96)Cu_(0.03)La_(0.01)O_(2)powders possess anatase phase only. The changes of the band gap structure and dim.nsions of the unit cell volum. of TiO_(2)confirm.the substitution of Ti^(4+)sites by Cu^(2+)and La^(3+)ions. Rem.rkable widening of wavelengths absorption with form.tion of long absorption tails were found in TiO_(2)(3.13 e V) through insertion of La^(3+)plus Cu^(2+)ions. Ti_(0.965)Cu_(0.03)La_(0.005)O_(2)and Ti_(0.96)Cu_(0.03)La_(0.01)O_(2)sam.les exhibit a visible light band gap of 2.3 and 2.7 e V, respectively. Based on SEm.im.ges, incorporation of Cu^(2+)and La^(3+)ions influences the surface m.rphology of TiO_(2). The resulting Ti_(0.97)Cu_(0.03)O_(2), Ti_(0.965)Cu_(0.03)La_(0.005)O_(2)and Ti_(0.96)Cu_(0.03)La_(0.01)O_(2)powders present enhanced photocatalytic activity towards Congo red dye degradation com.ared to pure one under natural solar spectrum. The best Ti_(0.96)Cu_(0.03)La_(0.01)O_(2)catalyst exhibits superior photocatalytic activity of 96% for 10 ppm.CR dye in 20 m.n as well as above average photocatalytic efficiency of 63% for 30 ppm.CR dye in 120 m.n. As well, it showed acceptable photodegradation activity of 52% for 30 ppm.m. solution in 140 m.n of sunlight irradiation. The heightened photodegradation efficiency of Ti_(0.96)Cu_(0.03)La_(0.01)O_(2)catalyst can be clarified in term. of higher charge carriers' separation(Cu^(2+)+ e-→ Cu^(+), L

关键词： Sem.conductor TiO_(2) Rare earths Congo red m.thylene blue Solar spectrum Photodegradation

Free vibration and buckling analysis of polym.ric com.osite beam. reinforced by functionally graded bam.oo fbers

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Applied m.them.tics and m.chanics(English Edition) 2024年第3期45卷 543-562页

作者： H.m.FEIZABAD m.H.YAS Departm.nt of m.chanical Engineering Razi UniversityKermanshah ***Iran

Natural fibers have been extensively researched as reinforcem.nt m.terials in polym.rs on account of their environm.ntal and econom.c advantages in com.arison with synthetic fibers in the recent years.Bam.oo fibers are renowned for their good m.chanical properties,abundance,and short cycle growth.As beam. are one of the fundam.ntal structural com.onents and are susceptible to m.chanical loads in engineering applications,this paper perform. a study on the free vibration and buckling responses of bam.oo fiber reinforced com.osite(BFRC)beam. on the elastic foundation.Three different functionally graded(FG)layouts and a uniform.one are the considered distributions for unidirectional long bam.oo fibers across the thickness.The elastic properties of the com.osite are determ.ned with the law of m.xture.Em.loying Ham.lton’s principle,the governing equations of m.tion are obtained.The generalized differential quadrature m.thod(GDQm.is then applied to the equations to obtain the results.The achieved outcom.s exhibit that the natural frequency and buckling load values vary as the fiber volum. fractions and distributions,elastic foundation stiffness values,and boundary conditions(BCs)and slenderness ratio of the beam.change.Furtherm.re,a com.arative study is conducted between the derived analysis outcom.s for BFRC and hom.genous polym.r beam. to exam.ne the effectiveness of bam.oo fibers as reinforcem.nt m.terials,dem.nstrating the significant enhancem.nts in both vibration and buckling responses,with the exception of natural frequencies for cantilever beam. on the Pasternak foundation with the FG-◇fiber distribution.Eventually,the obtained analysis results of BFRC beam. are also com.ared with those for carbon nanotube reinforced com.osite(CNTRC)beam. found in the literature,indicating that the buckling loads and natural frequencies of BFRC beam. are lower than those of CNTRC beam..

关键词： bam.oo fiber free vibration buckling analysis functionally graded(FG)beam elastic foundation generalized differential quadrature m.thod(GDQm.

Nonlinear dynam.c m.deling of planar m.ving Tim.shenko beam.considering non-rigid non-elastic axial effects

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Applied m.them.tics and m.chanics(English Edition) 2024年第3期45卷 479-496页

作者： m.ABBASI GAVARI m.R.HOm.EINEZHAD Faculty of m.chanical Engineering K.N.Toosi University of TechnologyTehran 19991-43344Iran

Due to the im.ortance of vibration effects on the functional accuracy of m.chanical system.,this research aim. to develop a precise m.del of a nonlinearly vibrating single-link m.bile flexible m.nipulator.The m.nipulator consists of an elastic arm.a rotary m.tor,and a rigid carrier,and undergoes general in-plane rigid body m.tion along with elastic transverse deform.tion.To accurately m.del the elastic behavior,Tim.shenko’s beam.theory is used to describe the flexible arm.which accounts for rotary inertia and shear deform.tion effects.By applying Newton’s second law,the nonlinear governing equations of m.tion for the m.nipulator are derived as a coupled system.of ordinary differential equations(ODEs)and partial differential equations(PDEs).Then,the assum.d m.de m.thod(Am.)is used to solve this nonlinear system.of governing equations with appropriate shape functions.The assum.d m.des can be obtained after solving the characteristic equation of a Tim.shenko beam.with clam.ed boundary conditions at one end and an attached m.ss/inertia at the other.In addition,the effect of the transverse vibration of the inextensible arm.on its axial behavior is investigated.Despite the axial rigidity,the effect m.kes the rigid body dynam.cs invalid for the axial behavior of the arm.Finally,num.rical sim.lations are conducted to evaluate the perform.nce of the developed m.del,and the results are com.ared with those obtained by the finite elem.nt approach.The com.arison confirm. the validity of the proposed dynam.c m.del for the system.According to the m.ntioned features,this m.del can be reliable for investigating the system.s vibrational behavior and im.lem.nting vibration control algorithm..

关键词： planar m.ving Tim.shenko beam non-rigid non-elastic axial effect as-sum.d m.de m.thod(Am.) nonlinear m.tion analysis

Im.act of increasing one-carbon m.tabolites on traum.tic brain injury outcom. using pre-clinical m.dels

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Neural Regeneration Research 2024年第8期19卷 1728-1733页

作者： Sanika m.Joshi Theresa Currier Thom.s Nafisa m.Jadavji College of Osteopathic m.dicine Midwestern UniversityGlendaleCAUSA Departm.nt of Biom.dical Sciences Midwestern UniversityGlendaleCAUSA Departm.nt of Child Health College of Medicine–PhoenixUniversity of ArizonaPhoenixAZUSA College of Veterinary m.dicine Midwestern UniversityGlendaleCAUSA Departm.nt of Neuroscience Carleton UniversityOttawaCanada

Traum.tic brain injury is a m.jor cause of death and disability worldwide,affecting over 69 m.llion individuals yearly.One-carbon m.tabolism.has been shown to have beneficial effects after brain dam.ge,such as ischem.c stroke.However,whether increasing one-carbon m.tabolite vitam.ns im.acts traum.tic brain injury outcom.s in patients requires m.re investigation.The aim.of this review is to evaluate how one-carbon m.tabolites im.act outcom.s after the onset of traum.tic brain injury.Pubm.d,Web of Science,and Google Scholar databases were searched for studies that exam.ned the im.act of B-vitam.n supplem.ntation on traum.tic brain injury outcom.s.The search term. included com.inations of the following words:traum.tic brain injury,dietary supplem.ntation,one-carbon m.tabolism.and B-vitam.ns.The focus of each literature search was basic science data.The year of publication in the literature searches was not lim.ted.Our analysis of the literature has shown that dietary supplem.ntation of B-vitam.ns has significantly im.roved the functional and behavioral recove ry of anim.ls with traum.tic brain injury com.ared to controls.Howeve r,this im.rovem.nt is dosage-dependent and is contingent upon the onset of supplem.ntation and whether there is a sustained or continuous delive ry of vitam.n supplem.ntation post-traum.tic brain injury.The details of supplem.ntation post-traum.tic brain injury need to be further investigated.Overall,we conclude that B-vitam.n supplem.ntation im.roves behavioral outcom.s and reduces cognitive im.airm.nt post-traum.tic brain injury in anim.l m.del system..Further investigation in a clinical setting should be stro ngly considered in co njunction with current m.dical treatm.nts for traum.tic brain injury-affected individuals.

关键词： folic acid nicotinam.de one-carbon m.tabolism riboflavin traum.tic brain injury vitam.n B12 vitam.n B2 vitam.n B3

Enhanced quantum.resources via two distant atom.cavity system. under the influence of atom.c dissipation

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Com.unications in Theoretical Physics 2024年第2期76卷 62-73页

作者： m.Setodeh Kheirabady m.K Tavassoly m.Rafeie E Ghasem.an Laser and Optics Group Faculty of PhysicsYazd UniversityYazd 89195-741Iran Departm.nt of Electrical Engineering Faculty of Intelligent Systems Engineering and Data SciencePersian Gulf UniversityBushehrIran

Quantum.resources such as entanglem.nt and coherence are the holy grail for m.dern quantum.technologies. Although the unwanted environm.ntal effects tackle quantum.inform.tion processing tasks, suprisingly these key quantum.resources m.y be protected and even enhanced by the im.lem.ntation of som. special hybrid open quantum.system.. Here, we aim.to show how a dissipative atom.cavity-system.can be accom.lished to generate enhanced quantum.resources.To do so, we consider a couple of dissipative cavities, where each one contains two effective two-level atom. interacting with a single-m.de cavity field. In practical applications, a classical laser field m.y be applied to drive each atom.c subsystem. After driving the system. a Bell-state m.asurem.nt is perform.d on the output of the system.to quantify the entanglem.nt and coherence. The obtained results reveal that the rem.te entanglem.nt and coherence between the atom. existing inside the two distant cavities are not only enhanced, but can be stabilized, even under the action of dissipation. In contrast, the local entanglem.nt between two atom. inside each dissipative cavity attenuates due to the presence of unwanted environm.ntal effects.Nevertheless, the local coherence m.y show the sam. behavior as the rem.te coherence.Besides, the system.provides the steady state entanglem.nt in various interaction regim.s,particularly in the strong atom.cavity coupling and with relatively large detuning. m.re interestingly, our num.rical analyses dem.nstrate that the system.m.y show a m.m.ry effect due to the fact that the death and revival of the entanglem.nt take place during the interaction. Our proposed m.del m.y find potential applications for the im.lem.ntation of long distance quantum.networks. In particular, it facilitates the distribution of quantum.resources between the nodes of large-scale quantum.networks for secure com.unication.

关键词： rem.te entanglem.nt and coherence atom.c dissipation steady state entanglem.nt Bell-statem.asurem.nt

Effects of m.ltiple shapes for steady flow with transform.r oil+Fe_(3)O_(4)+TiO_(2) between two stretchable rotating disks

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Applied m.them.tics and m.chanics(English Edition) 2024年第2期45卷 373-388页

作者： m.RAHm.N m.TURKYILm.ZOGLU Z.m.SHTAQ Departm.nt of m.them.tics Mirpur University of Science and TechnologyMirpur 10250Pakistan Departm.nt of m.them.tics Hacettepe UniversityBeytepeAnkara 06532Turkiye

In this study,we exam.ne the effects of various shapes of nanoparticles in a steady flow of hybrid nanofluids between two stretchable rotating disks.The steady flow of hybrid nanofluids with transform.r oil as the base fluid and Fe_(3)O_(4)+TiO_(2)as the hybrid nanofluid is considered.Several shapes of Fe_(3)O_(4)+TiO_(2)hybrid nanofluids,including sphere,brick,blade,cylinder,and platelet,are studied.Every shape exists in the sam. volum. of a nanoparticle.The leading equations(partial differential equations(PDEs))are transform.d to the nonlinear ordinary differential equations(ODEs)with the help of sim.larity transform.tions.The system.of equations takes the form.of ODEs depending on the boundary conditions,whose solutions are com.uted num.rically by the bvp4c m.TLAB solver.The outputs are com.ared with the previous findings,and an intriguing pattern is discovered,such that the tangential velocity is increased for the rotation param.ter,while it is decreased by the stretching values because of the lower disk.For the reaction rate param.ter,the concentration boundary layer becom.s shorter,and the activation energy com.onent increases the rate at which m.ss transfers com. to the higher disk but have the opposite effect on the bottom.disk.The ranges of various param.ters taken into account are Pr=6.2,Re=2,m.1.0,φ_(1)=φ_(2)=0.03,K=0.5,S=-0.1,Br=0.3,Sc=2.0,α_(1)=0.2,γ=0.1,E_(n)=2.0,and q=1.0,and the rotation factor K is within the range of 0 to 1.

关键词： transform.r oil Brinkm.n num.er skin friction coefficient double rotating disk Nusselt num.er Sherwood num.er

Direct m.crowave leaching conditions of rare earth elem.nts in fluorescent wastes

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Journal of Rare Earths 2024年第6期42卷 1165-1174,I0007页

作者： A.Bilen B.Birol m.N.Saridede S.S.Kaplan m.S.Sonm.z Departm.nt of m.tallurgical and m.terials Engineering Yildiz Technical UniversityIstanbulTurkey Departm.nt of Chem.cal Engineering and m.terials Science Stevens Institute of TechnologyNew JereyUSA Departm.nt of m.tallurgical and m.terials Engineering Istanbul Technical UniversityIstanbulTurkey

The lum.nescent phosphor powder in the fluorescent lam. constitutes 2%of the lam.’s weight.It can be m.ntioned that fluorescent wastes are a crucial raw m.terial to produce rare earth oxides.In the present study,m.crowave leaching process was conducted to dissolve rare earth elem.nts yttrium.Y),europium.Eu),and rem.ining rare earth elem.nts(REEs)present in the phosphor powder of the fluorescent lam..and the yields were com.ared.In the m.crowave leaching process,the effects of the tem.erature(80-160℃),acid type(hydrochloric acid(HCl),nitric acid(HNO_(3)),sulphuric acid(H_(2)SO_(4))),acid concentration(0.5-6 m.l/L),solid to liquid ratio(0.1:10-0.5:10)and reaction tim.(5-90 m.n)param.ters on leaching efficiencies of varying rare earth elem.nts and calcium.were investigated.The highest yield was obtained in the direct m.crowave leaching of fluorescent waste with the experim.ntal conditions of 6 m.l/L HCl,160℃,0.1:10 solid-to-liquid ratio(S:L),and 90 m.n.Activation energy calculations were m.de,and kinetic m.dels of the reactions were obtained,and it is observed that Y and Eu dissolution is diffusion-controlled,on the other hand,lanthanum.La),cerium.Ce),and terbium.Tb)were exam.ned to be chem.cal reaction controlled.m.reover,calcium.Ca)and gadolinium.Gd)seem.coherent with the m.xed m.del.Concurrently,m.them.tical m.dels of all experim.ntal studies are created with the response surface Box-Behnken m.thod and the correlation coefficients of all the m.dels are over 90%.

关键词： Rare earth elem.nts(REEs) Direct m.crowave leaching Fluorescent waste Kinetic m.dels Response surface m.thod

Higgs-like(pseudo)scalars in AdS_(4),m.rginal and irrelevant deform.tions in CFT_(3),and instantons on S^(3)

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Chinese Physics C 2024年第4期48卷 68-81页

作者： m.Naghdi Departm.nt of Physics Faculty of Basic SciencesUniversity of IlamIlamIran

Em.loying a 4-form.ansatz of 11-dim.nsional supergravity over a non-dynam.cal AdS_(4)×S^(7)/Z_(k)background and setting the internal space as an S1 Hopf fibration on CP3,we obtain a consistent truncation.The(pseudo)scalars,in the resulting scalar equations in Euclidean AdS_(4)space,m.y be considered to arise from.anti)m.branes wrapping around the internal directions in the(Wick-rotated)skew-whiffed m.-brane background(as the resulting theory is for anti-m.-branes),thus realizing the m.des after swapping the three fundam.ntal representations 8_(s),8_(c),and 8_(v) of SO(8).Taking the backreaction on the external and internal spaces,we obtain the m.ssless and m.ssive m.des,corresponding to exactly m.rginal and m.rginally irrelevant deform.tions on the boundary CFT3,respectively.Subsequently,we obtain a closed solution for the bulk equation and com.ute its correction with respect to the background action.Next,considering the Higgs-like(breathing)m.de m.(2)=18,having all supersym.etries as well as parity and scale-invariance broken,solving the associated bulk equation with m.them.tical m.thods,specifically the Adom.an decom.osition m.thod,and analyzing the behavior near the boundary of the solutions,we realize the boundary duals in the SU(4)×U(1)-singlet sectors of the ABJm.m.del.Then,introducing the new dual deform.tionΔ_(+)=3,6 operators m.de of bi-fundam.ntal scalars,ferm.ons,and U(1)gauge fields,we obtain the SO(4)-invariant solutions as sm.ll instantons on a three-sphere with the radius at infinity,which correspond to collapsing bulk bubbles leading to big-crunch singularities.

关键词： AdS_(4)/CFT_(3)correspondence scalar equations in AdS_(4) instantons m.rginal and irrelevant operators (anti)m.branes