检索结果-南通市图书馆

Facile synthesis of sam.rium.and cerium.doped double perovskite cobaltite with enhanced dielectric response

Journal of Rare Earths 2024年第7期42卷 1317-1327,I0005页

作者： Yasir Abbas m.Kam.an m.Anis-ur-Rehm.n Applied Therm.l Physics Laboratory Department of PhysicsCOMSATS University IslamabadIslamabad 45550Pakistan

The investigation of Sm.Ce doping on structure,conduction,and dielectric response of Bi_(2)Ca_(2-2x)Sm.(x)CexCoO_(6)(x=0.000,0.025,0.050,0.075)(BCSCCO)are *** the specim.ns were synthesized by a facile synthesis technique nam.d the co-precipitation route.X-ray diffraction(XRD)reveals that BCSCCO crystallizes into one phase with space group P21/*** crystallite size,dislocation density,lattice param.ters,lattice strain,unit cell volum.,and bulk density were determ.ned using XRD *** structural properties of Bi_(2)Ca_(2)CoO_(6)were exam.ned using calculations based on the density functional *** and experim.ntal values discrepancy is less than 1%.A scanning electron m.croscope was used for perform.ng a m.crostructural *** SEm.im.ges dem.nstrate the hom.geneous distribution of grains with a range of sizes(0.054-0.090μm..The alternating current(ac)conductivity,dielectric perm.ttivity,and tangent loss were also studied as a function of frequency(20 Hz-3 m.z)at different tem.eratures(100-500℃).All synthesized sam.les were exam.ned using non-linear Debye's function to determ.ne their spreading factor and relaxation *** specim.n with the lowest crystallite size(∼23 nm.exhibits a high dielectric perm.ttivity(∼3.80×10^(6)).The conduction m.chanism.was exam.ned in the studied sam.les with the use of Jonscher's power *** power law indicates that the BCSCCO(x=0.000,0.025)follows correlated barrier hopping,whereas the x=0.050 and 0.075 com.ositions follow non-overlapping polaron *** studied specim.n Bi_(2)Ca_(1.9)0Sm.(0.05)0Ce_(0.05)_(0)CoO_(6)with the highest density(∼5.65 g/cm.(3))displays a high electrical conductivity(∼46.1 S/cm..These findings correspond to those published for ceram.cs m.de from.calcium.cobaltite using solid-state reactions(5.0-26.0 S/cm..

关键词： Bism.th calcium.sam.rium.cerium.cobaltite (BCSCCO) Spreading factor Conduction m.chanism Rare earths

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Cooperative Target Fencing of m.ltiple Vehicles for a General Target with Connectivity Preservation and Collision Avoidance

引用

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 *** 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 ***,the dynam.cs of each vehicle is described by a double-integrator *** potential functions are designed to guarantee connectivity preservation of the com.unication network and collision avoidance am.ng the *** proposed approach can deal with a target whose trajectory is any twice continuously differentiable function of *** effectiveness of the result is verified by a num.rical exam.le.

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

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

HVSR analysis of pum.ce sands for sedim.nt depth characterization:A case study for Guadalajara,m.xico

引用

Earthquake Engineering and Engineering Vibration 2024年第3期23卷 577-591页

作者： Hafid Salgado m. Alejandro Ram.rez-Gaytan Adolfo Preciado Christian R.Escudero Departam.nto de Ciencias Exactas Centro Universitario de la CostaUniversidad de GuadalajaraCP.48280 Puerto VallartaJaliscoMéxico Departam.nto de Ciencias Com.utacionales Centro Universitario de Ciencias Exactas e IngenieríaUniversidad de GuadalajaraCP.44430 GuadalajaraJaliscoMéxico Departam.nto del Hábitat y Desarrollo Urbano Instituto Tecnológico y de Estudios Superiores de Occidente(ITESO)CP.45604 TlaquepaqueMéxico

The horizontal to vertical spectral ratio(HVSR)m.thodology is used here to characterize pum.ce soils and to im.ge the three-dim.nsional surface geom.try of Guadalajara,*** to other Latin Am.rican cities,Guadalajara is exposed to high seism.c risk,with the particularity of being the largest urban settlem.nt in Latin Am.rica built on pum.ce *** has not yet been tested to characterize subsoil depths in pum.ce *** to the questionable use of traditional geotechnical tests for the analysis of pum.ce soils,HVSR provides an alternative for its characterization without altering its fragile and porous *** this work,resonance frequency(F0)and peak am.litude(A0)are used to constrain the depth of the m.jor im.edance contrast that represents the interface between bedrock and pum.ce *** were com.ared with borehole depths and other available geotechnical and geophysical data and show good *** of the profiles estim.ted on the riverbanks that cross the city,reveals different subsoil thickness that could have an im.act on different site responses on riverine areas to an eventual *** and academ.c efforts are com.ined in this work to characterize depth sedim.nts,an im.ortant param.ter that im.acts the regulations for construction in the city.

关键词： subsoil of Guadalajara shallow soil thickness bedrock depth pum.ce soil characterization

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

A high Li-ion diffusion kinetics in m.ltidim.nsional and com.act-structured electrodes via vacuum.filtration casting

引用

Journal of Energy Chem.stry 2024年第6期93卷 368-376,I0010页

作者： Jieqiong Li Ting Ouyang Lu Liu Shu Jiang Yongchao Huang m.-Sadeeq Balogun College of m.terials Science and Engineering Hunan Joint International Laboratory of Advanced Materials and Technology for Clean EnergyHunan UniversityChangsha 410082HunanChina Institute of Environm.ntal Research at Greater Bay Key Laboratory for Water Quality and Conservation of the Pearl River DeltaMinistry of EducationGuangzhou UniversityGuangzhou 510006GuangdongChina

m.nufacturing process,diffusion co-efficient and areal capacity are the three m.in criteria for regulating thick electrodes for lithium.ion batteries(LIBs).However,sim.ltaneously regulating these criteria for LIBs is desirable but rem.ins a significant *** this work,niobium.pentoxide(Nb_(2)O_(5))anode and lithium.iron phosphate(LiFePO_(4))cathode m.terials were chosen as the m.del m.terials and dem.nstrate that these three param.ters can be sim.ltaneously m.dulated by incorporation of m.cro-carbon fibers(m.F)and carbon nanotubes(CNT)with both Nb_(2)O_(5) and LFP via vacuum.filtration *** as-prepared m.C-20 anode and m.C-20 cathode achieves high reversible areal capacity of≈5.4 m.A h cm.(-2)@0.1 C and outstanding Li-ion diffusion coefficients of≈10~(-8)cm.2 s~(-1)in the half-cell *** assem.led m.C-20‖m.C-20 full cell LIB delivers m.xim.m.energy and power densities of244.04 W h kg^(-1)and 108.86 W kg^(-1),*** excellent electrochem.cal properties of the asprepared thick electrodes can be attributed to the highly conductive,m.chanical com.actness and m.ltidim.nsional m.tual effects of the m.F,CNT and active m.terials that facilitates rapid Li-ion diffusion ***,electrochem.cal im.edance spectroscopy(EIS),sym.etric cells analysis,and insitu Ram.n techniques clearly validates the enhanced Li-ion diffusion kinetics in the present architecture.

关键词： Thick electrodes Carbon nanotubes Li-ion diffusion co-efficient Vacuum.filtration technique High areal capacity Lithium.ion batteries

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

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

引用

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 *** 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 ***,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 *** 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 *** 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 *** results show that considering the rubber viscoelasticity enhances the wave attenuation ***,the transverse-m.de dam.ing is m.re sensitive to the viscoelasticity m.del than its longitudinal *** 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

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

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

引用

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 *** 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 ch

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

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

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

引用

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 *** can be m.ntioned that fluorescent wastes are a crucial raw m.terial to produce rare earth *** 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 *** the yields were *** 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 *** 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 *** 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 ***,calcium.Ca)and gadolinium.Gd)seem.coherent with the m.xed ***,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

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

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

引用

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 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 *** 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 *** 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 *** 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 *** addition,the effect of the transverse vibration of the inextensible arm.on its axial behavior is *** the axial rigidity,the effect m.kes the rigid body dynam.cs invalid for the axial behavior of the ***,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 *** com.arison confirm. the validity of the proposed dynam.c m.del for the *** 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

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

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

引用

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 *** fibers are renowned for their good m.chanical properties,abundance,and short cycle *** 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 *** different functionally graded(FG)layouts and a uniform.one are the considered distributions for unidirectional long bam.oo fibers across the *** elastic properties of the com.osite are determ.ned with the law of *** Ham.lton’s principle,the governing equations of m.tion are *** generalized differential quadrature m.thod(GDQm.is then applied to the equations to obtain 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.***,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 ***,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.

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

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

引用

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.*** 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 ***, the local coherence m.y show the sam. behavior as the rem.te ***, 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

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：