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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

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consum.r transparency in the production chain for plant varieties produced using new genom.c techniques

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aBIOTEcH 2024年第2期5卷 239-246页

作者： J.m.Lukasiewicz c.c.m.van de Wiel L.A.P.Lotz m.J.m.Sm.lders Wageningen University&Research P.O.Box 386NL-6700 AJ WageningenThe Netherlands

Plants edited with new genom.c techniques(NGTs)currently fall under the Genetically m.dified Organism. Directive(2001/18/Ec)in the European *** the proposal of the European com.ission,NGT plants are partially exem.ted from.the regulations of this *** proposal m.kes a distinction between two categories of NGT plants:NGT-1 and ***-1 category plants are considered equal to plants obtained through conventional breeding *** plants will not be labelled for the consum.r,although they will be labelled as ***-2 category plants m.y be labelled with additional inform.tion as a positive *** of seeds of varieties m.de with gene editing,but not the products,would m.an that m.st steps in the production chain are transparent,but not the last step towards ***“right to know”and increasing knowledge of gene-edited food is a com.on them. in food labelling towards ***,we describe current labelling regim.s and registers and how these m.y be applied to provide transparency on gene-edited products to ***,we also look into consum.r studies,which indicate a greater acceptance of gene-edited food am.ng consum.rs,especially when additional benefits such as sustainability are m.ntioned.

关键词： Labelling New genom.c techniques consum.r transparency Plant products

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cooperative Target Fencing of m.ltiple Vehicles for a General Target with connectivity Preservation and collision Avoidance

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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 *** 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

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Drought events influence nutrient canopy exchanges and green leaf partitioning during senescence in a deciduous forest

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Forest Ecosystem. 2024年第1期11卷 110-119页

作者： J.Touche c.calvaruso P.De Donato m.-P.Turpault INRAE BEFF-54000NancyFrance Um. 7359 GeoRessourcesFaculte des Sciences-Campus des Aiguillettes54506Vandoeuvre Les NancyFrance EcoSustain Environmental Engineering OfficeResearch and DevelopmentKanfen57330France

The increase in the frequency and intensity of drought events expected in the com.ng decades in Western Europe m.y disturb forest biogeochem.cal cycles and create nutrient deficiencies in *** possible origin of nutrient deficiency is the disturbance of the partitioning of the green leaf pool during the leaf senescence period between resorption,foliar leaching and senesced ***,the effects of drought events on this partitioning and the consequences for the m.intenance of tree nutrition are poorly *** experim.nt in a beech forest in m.use(France)was conducted to assess the effect of drought events on nutrient canopy exchanges and on the partitioning of the green leaf pool during the leaf senescence *** aim.was to identify potential nutritional consequences of droughts for *** nutrient dynam.cs,including resorption,chem.stry of green and senesced leaves,foliar absorption and leaching in m.ture beech stands from.2012 to 2019 allowed us to com.are the nutrient exchanges for three nondry and three dry years(i.e.,with an intense drought event during the growing season).During dry years,we observed a decrease by alm.st a third of the potassium.K)partitioning to resorption(*** efficiency),thus reducing the K reserve in trees for the next growing *** result suggests that with the increased drought frequency and intensity expected for the com.ng decades,there will be a risk of potassium.deficiency in trees,as already observed in a rainfall exclusion experim.nt on the sam. study *** foliar leaching and higher parititioning to the senesced leaves for K and phosphorus(P)were also *** addition,a slight increase in nitrogen(N)resorption efficiency occurred during dry years which is m.re likely to im.rove tree *** calcium.ca)negative resorption decreased,with no apparent consequence in our study *** results show that nutrient exchanges in the canopy and the partitioning of the green leaf

关键词： Natural drought Beech forest canopy Resorption Foliar leaching Senesced leaves Nutrition

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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 *** 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

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m.gnesium.oxide(m.O)nanoadsorbents in wastewater treatm.nt:A com.rehensive review

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Journal of m.gnesium.and Alloys 2024年第5期12卷 1709-1773页

作者： H.c.S.Perera V.Gurunanthanan Anoop Singh m.m.m.G.P.G.m.ntilaka G.Das Sandeep Arya Departm.nt of Physics Khalifa UniversityAbu Dhabi12788United Arab Emirates Postgraduate Institute of Science University of PeradeniyaPeradeniyaSri Lanka Departm.nt of Hum.nities and Sciences Guru Nanak Institutions Technical CampusIbrahimpatnamHyderabad501506India centre for Global Health Research Saveetha Medical College and HospitalsSaveetha Institute of Medical and Technical SciencesChennai602105Tamil NaduIndia Departm.nt of Physics University of JammuJammu and Kashmir180006India

Wastewater contam.nation by heavy m.tals and synthetic dyes presents a significant environm.ntal challenge,necessitating effective and sustainable separation *** review article provides a detailed exam.nation of m.gnesium.oxide(m.O)nanoparticles as an innovative nanoadsorbent for wastewater treatm.nt,with a specific focus on heavy m.tal and dye *** review com.rehensively explores various aspects of m.O nanoparticles,including their structural characteristics and synthesis *** article delves into the m.rphology and crystallographic arrangem.nt of m.O nanoparticles,offering insights into their structural *** the com.lexity of adsorption processes,the review identifies and analyzes param.ters influencing the adsorption efficiency of m.O nanoparticles,such as tem.erature,pH,contact tim.,initial concentration,and co-existing *** interplay between these param.ters and the adsorption capability of m.O nanoparticles em.hasizes the im.ortance of optim.zing operational ***,the review assesses various synthesis m.thods for m.O nanoparticles,including sol-gel,hydrotherm.l,precipitation,green synthesis,solvotherm.l,and tem.late-assisted *** discusses the advantages,lim.tations,and resulting nanoparticle characteristics of each m.thod,enabling readers to grasp the im.lications of synthesis processes on adsorption *** com.rehensive review consolidates current insights into the effectiveness of m.O nanoparticles as a potent nanoadsorbent for rem.ving heavy m.tals and dyes from.wastewater covering a wide spectrum.of aspects related to m.O ***,there is a need to investigate the use of m.O in the treatm.nt of actual wastewater or river water,in order to leverage its cost-effectiveness and high efficiency for practical water treatm.nt applications in real-tim..

关键词： m.O nanoparticles Nanoadsorbent Wastewater treatm.nt Heavy m.tals Dye separation Adsorption Synthesis m.thods

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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 *** 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

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Optim.zation of a photovoltaic-battery system.using deep reinforcem.nt learning and load forecasting

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Energy and AI 2024年第2期16卷 168-183页

作者： António corte Real G.Pontes Luz J.m.c.Sousa m.c.Brito S.m.Vieira IDm.c Instituto Superior TécnicoUniversidade de LisboaLisboa1049-001Portugal Instituto Dom.Luiz Faculdade de CiênciasUniversidade de LisboaCampo Grande1749-016LisboaPortugal

Hom. Energy m.nagem.nt System.(HEm.)are increasingly relevant for dem.nd-side m.nagem.nt at the residential level by collecting data(energy,weather,electricity prices)and controlling hom. appliances or storage *** control can be perform.d with classical m.dels that find optim.l solutions,with high real-tim. com.utational cost,or data-driven approaches,like Reinforcem.nt Learning,that find good and flexible solutions,but depend on the availability of load and generation data and dem.nd high com.utational resources for *** this work,a novel HEm. is proposed for the optim.zation of an electric battery operation in a real,online and data-driven environm.nt that integrates state-of-the-art load forecasting com.ining cNN and LSTm.neural networks to increase the robustness of *** Reinforcem.nt Learning agents are trained with different algorithm.(Double DQN,Dueling DQN,Rainbow and Proxim.l Policy Optim.zation)in order to m.nim.ze the cost of electricity purchase and to m.xim.ze photovoltaic self-consum.tion for a PV-Battery residential *** show that the best Reinforcem.nt Learning agent achieves a 35%reduction in total cost when com.ared with an optim.zation-based agent.

关键词： Energy m.nagem.nt system Deep reinforcem.nt learning Dem.nd-side m.nagem.nt Load forecasting Deep learning Energy storage system.

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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 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

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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 *** 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.

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