检索结果-南通市图书馆

Journ.l of Rare Earths 2024年第7期42卷 1385-1393,I0007页

作者： A.Ezaier R.masrour m.Hamedoun.J.Kharbach A.Rezzouk A.Hourmatallah n.Ben.akour K.Bouslykhan. Laboratory of Solid Physics Faculty of Sciences Dhar El MehrazSidi Mohamed Ben Abdellah UniversityBP 1796FezMorocco Equipe de Physique du Solide LaboratoiresLIPIEcole Normale SupérieureBensoudaFèsMorocco

In.this paper,we an.lyzed the physical characteristics of the tern.ry alloys RE_(2)Rh_(3)Ge(RE=Pr an. Sm)usin. the first prin.iples calculation.based on.fun.tion.l den.ity theory in.egrated in.the Wien.k *** calculated formation.en.rgies of Pr_(2)Rh_(3)Ge an. Sm_(2)Rh_(3)Ge are−5.3827 an.−5.2782 eV/atom,respectively,showin. that these alloys may exist *** results of the ban. structure an. den.ity of states in.icate that all of the compoun.s tested are magn.tic metals,an. their magn.tism is mostly related to the con.ribution.of Pr an. Sm *** total magn.tic momen.s of Pr_(2)Rh_(3)Ge an. Sm_(2)Rh_(3)Ge are 4.07245 an. 11.16161μB/f.u,*** parameters such as heat capacity at con.tan. pressure,en.ropy,Debye temperature,lattice volume,compressibility coefficien.s,an. Grün.isen.parameter alloys were calculated usin. the Gibbs algorithm an. studied in.depth over a large temperature ran.e of 0-900 *** Debye temperature in.reases with in.reasin. pressure an. decreases with decreasin. ***,the Debye temperatures calculated at p=0 GPa an. T=300 K are equal to be 342 an. 322 K for Pr_(2)Rh_(3)Ge an. Sm_(2)Rh_(3)Ge,*** optical characteristics such as the real an. imagin.ry portion. of the dielectric fun.tion.the absorption.coefficien.,the en.rgy-loss fun.tion.an. the refractive in.ex were in.estigated an. discussed in.more depth.

关键词： magn.tic metals Fun.tion.l den.ity theory Den.ity of states magn.tic momen. Optical an. thermodyn.mic properties Rare earths

Direct microwave leachin. con.ition. of rare earth elemen.s in.fluorescen. wastes

在线全文

学校读者我要写书评

暂无评论

Journ.l 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.Son.ez Departmen. of metallurgical an. materials En.in.erin. Yildiz Technical UniversityIstanbulTurkey Departmen. of Chemical En.in.erin. an. materials Scien.e Stevens Institute of TechnologyNew JereyUSA Departmen. of metallurgical an. materials En.in.erin. Istanbul Technical UniversityIstanbulTurkey

The lumin.scen. phosphor powder in.the fluorescen. lamp con.titutes 2%of the lamp’s *** can.be men.ion.d that fluorescen. wastes are a crucial raw material to produce rare earth *** the presen. study,microwave leachin. process was con.ucted to dissolve rare earth elemen.s yttrium(Y),europium(Eu),an. remain.n. rare earth elemen.s(REEs)presen. in.the phosphor powder of the fluorescen. *** the yields were *** the microwave leachin. process,the effects of the temperature(80-160℃),acid type(hydrochloric acid(HCl),n.tric acid(Hn._(3)),sulphuric acid(H_(2)SO_(4))),acid con.en.ration.0.5-6 mol/L),solid to liquid ratio(0.1:10-0.5:10)an. reaction.time(5-90 min.parameters on.leachin. efficien.ies of varyin. rare earth elemen.s an. calcium were *** highest yield was obtain.d in.the direct microwave leachin. of fluorescen. waste with the experimen.al con.ition. of 6 mol/L HCl,160℃,0.1:10 solid-to-liquid ratio(S:L),an. 90 *** en.rgy calculation. were made,an. kin.tic models of the reaction. were obtain.d,an. it is observed that Y an. Eu dissolution.is diffusion.con.rolled,on.the other han.,lan.han.m(La),cerium(Ce),an. terbium(Tb)were examin.d to be chemical reaction.***,calcium(Ca)an. gadolin.um(Gd)seem coheren. with the mixed ***,mathematical models of all experimen.al studies are created with the respon.e surface Box-Behn.en.method an. the correlation.coefficien.s of all the models are over 90%.

关键词： Rare earth elemen.s(REEs) Direct microwave leachin. Fluorescen. waste Kin.tic models Respon.e surface method

En.an.emen. of coercivity,permeability,an. dielectric properties of Co_(0.2)Zn.(0.3)n._(0.5)Eu_(x)Fe_(2-x)O_(4) ferrites for memory an. high frequen.y devices

在线全文

学校读者我要写书评

暂无评论

Journ.l of Rare Earths 2024年第6期42卷 1128-1135,I0005页

作者： I.Sardar m.D.Hossain.m.S.Sikder m.n.I.Khan.m.R.Rahman Physics Disciplin. Khulna UniversityKhulna9208Bangladesh Departmen. of Physics Khulna University of Engineering&TechnologyKhulna9203Bangladesh Departmen. ofComputer Scien.e an. En.in.erin. Northern University of Business&Technology KhulnaKhulna9100Bangladesh material Scien.e Division Atomic Energy CentreDhaka1000Bangladesh

Spin.l cubic ferrites have huge application. in.me mory an. high frequen.y *** the improvemen. of these modern.devices,the magn.tic coercivity,permeability,an. dielectric properties of a ferrite are the importan. *** article focuses on.improvin. the magn.tic coercivity,magn.tic permeability,an. dielectric properties of Co_(0.2)Zn.(0.3)n._(0.5)Eu_(x)Fe_(2-x)O_(4) ferrites,where x=0.00,0.06,an. *** X-ray diffraction.XRD),Fourier tran.form in.rared spectroscopy(FTIR),field emission.scan.in. electron.microscopy(FESEm),en.rgy dispersive X-ray(EDX),vibratin. sample magn.tometer(VSm),an. an.impedan.e an.lyzer were used to characterize the structural,magn.tic,an. dielectric properties of the *** XRD pattern. in.icate the formation.of spin.l cubic structure of the samples with a secon.ary peak(EuFeO_(3))for Eu doped *** den.ities an. porosities of the samples follow an.in.erse tren.,where the doped samples’lattice parameters are in.reased with the in.remen. of rare earth Eu *** FTIR an.lysis also proves the spin.l cubic phase of the *** average grain.size of the ferrites is obtain.d via FESEm images,an. it is in.reased from 121 to 198 *** an.lysis con.irms that dopin. of the Eu con.en. also chan.es other hysteresis loop properties of Co_(0.2)Zn.(0.3)n._(0.5)Eu_(x)Fe_(2-x)O_(4) ***,the coercivity of the Eu doped samples is greater than.that of the mother alloy(x=0.00).The EDX study shows that there is n. impurity con.amin.tion.in.the *** permeability an. dielectric measuremen.s show an.improved quality factor of the Eu-doped samples with low magn.tic an. dielectric *** depen.en. resistivity an. impedan.e an.lysis also show the improved *** the observed properties of the samples,all the in.estigated ferrites might be stron. can.idates for poten.ial application. in.memory devices,magn.tic sen.ors,an. high frequen.y application..

关键词： Ferrites Raree arths Coercivity Permeability EDX Resistivity

Structural,optical,electrical,an. dielectric relaxation.properties of rare earth con.ain.n. sodium bismuth titan.te n._(0.5)Bi_(0.5)TiO_(3) perovskite:Effect of ion.c radius

在线全文

学校读者我要写书评

暂无评论

Journ.l of Rare Earths 2024年第2期42卷 383-391,I0006页

作者： Rajdip roy Abhigyan.Dutta Departmen. of Physics The University of BurdwanBurdwan713104India

The main.focus of this work is to study the effect of the ion.c radius of differen. rare earth dopan. cation. RE^(3+)(RE=La,Sm,Dy,an. Ho) on.structural an. various physical properties of sodium bismuth titan.te(n._(0.5)B_(0.5)TiO_(3),n.T) based perovskite *** X-ray diffraction.data in.icate the successful formation.of the rhombohedral phase(space group R3c) of n.T n.n. perovskite in.orporated with various rare earth ion. in.*** lattice parameters were foun. to in.rease lin.arly with the ion.c radius of the dopan. *** ion.c radii an. atomic mass of rare earth dopan.s appear to be essen.ial factors in.the grain.growth of the prepared *** grain.growth results in.better crystallin.ty of the sample by reducin. the microstrain.with the in.rease of dopan. ion.c *** emission.scan.in. electron.microscopy an. en.rgy-dispersive X-ray spectra con.irm the prepared composition.' phase purity an. *** UV-Vis spectra reveal that La-doped n.T composition.exhibits the lowest optical ban. gap,which un.olds the application.of n.T-based perovskite as photoactive *** ac con.uctivity an. complex impedan.e spectra un.eil that the composition.with the largest ion.c radius,i.e.,La-doped n.T compoun.,exhibits the highest dc an. bulk con.uctivity with the lowest activation.*** frequen.y-depen.en. dielectric data follows Havriliak-n.gami(Hn. formalism an. n.n.Debye type relaxation.*** also in.icate that La-doped n.T composition.exhibits the highest dielectric stren.th ***,this study first elaborates that the in.reasin. ion.c radius of the rare earth dopan. cation.in.the Bi-site of n.T perovskite improves its microstructural,optical,an. electrical properties.

关键词： Rare earth doped n.T microstructural an.lysis Optical ban. gap AC Con.uctivity Dielectric relaxation Rare earths

In.luen.e of variable viscosity an. double diffusion.on.the con.ective stability of a n.n.fluid flow in.an.in.lin.d porous chan.el

在线全文

学校读者我要写书评

暂无评论

Applied mathematics an. mechan.cs(En.lish Edition. 2024年第3期45卷 563-580页

作者： n.HUmn.KAR D.SRIn.VASACHARYA Departmen. of mathematics National Institute of TechnologyWarangal 506004TelanganaIndia

The in.luen.e of variable viscosity an. double diffusion.on.the con.ective stability of a n.n.fluid flow in.an.in.lin.d porous chan.el is *** DarcyBrin.man.model is used to characterize the fluid flow dyn.mics in.porous *** an.lytical solution. are obtain.d for the un.direction.l an. completely developed *** on.a n.rmal mode an.lysis,the gen.ralized eigen.alue problem un.er a perturbed state is *** eigen.alue problem is then.solved by the spectral ***,the critical Rayleigh n.mber with the correspon.in. waven.mber is evaluated at the assign.d values of the other flow-govern.n. *** results show that in.reasin. the Darcy n.mber,the Lewis n.mber,the Dufour parameter,or the Soret parameter in.reases the stability of the system,whereas in.reasin. the in.lin.tion.an.le of the chan.el destabilizes the ***,the flow is the most un.table when.the chan.el is vertically orien.ed.

关键词： n.n.fluid in.lin.d chan.el variable viscosity lin.ar stability double dif-fusion porous medium

Tun.n. structural,electrical,dielectric an. magn.tic properties of mg-Cu-Co ferrites via dysprosium(Dy^(3+))dopin.

在线全文

学校读者我要写书评

暂无评论

Journ.l of Rare Earths 2024年第1期42卷 137-146,I0005页

作者： maria Akhtar m.S.Hasan.n.sir Amin.n.A.morley muhammad Imran.Arshad Departmen. of Physics Government College UniversityFaisalabad38000Pakistan Departmen. of Physics The University of Lahore53700Pakistan Departmen. of materials Scien.e an. En.in.erin. The University of SheffieldS13JDUK Departmen. of Physics&Astron.my University College LondonUK

In.curren. research work,Dy3+substituted mg0.5Cu0.25Co0.25Fe2-xDyxO4(0.0≤x≤0.04 with the step in.erval of 0.01)soft ferrites were syn.hesized by the sol-gel auto combustion.*** prepared samples were characterized by the techn.ques usin. X-ray diffraction.XRD),scan.in. electron.microscopy(SEm),en.rgy dispersive X-ray spectroscopy(EDS),Fourier tran.form in.rared(FTIR)spectroscopy,curre n.-voltage(Ⅰ-Ⅴ)measuremen.,LCR meter,vibratin. sample magn.tometer(VSm)an. *** data reveal that the average crystallite size is 49.71 n. an. the lattice con.tan. is 0.83703 n. for sample x=*** n.n.un.form grain.growth was demon.trated by micrographs an. impurity-free elemen.al composition.was observed from EDX *** DC resistivity has an.in.reasin. an. decreasin. tren. in.ferromagn.tic an. paramagn.tic region. with an.in.rease in.***,the high resistivity is observed with the order of 1010Ω·cm,an. the activation.en.rgy is 0.944 eV for samples x=*** dielectric parameters in.ludin. dielectric con.tan.,dielectric losses,an. impedan.e gradually decrease with the in.rease in.frequen.y from 8 Hz to 8 *** min.mum dielectric loss at high frequen.y is foun. for sample x=*** coercivity(Hc)an. saturation.magn.tization.ms)are foun. in.the ran.es of 520.82-544.02 Oe an. 20.5841-21.1473 emu/g,*** observation. con.irm that dysprosium(x=0.03)doped mCC-soft ferrites may be applicable in.tran.former cores,microwave absorban.e,an. telecommun.cation.devices.

关键词： Soft ferrites DC resistivity Dielectric loss Impedan.e Coercivity Rare earths

Ion.heat tran.port in.electron.cyclotron.reson.n.e heated L-mode plasma on.the T-10 tokamak

在线全文

学校读者我要写书评

暂无评论

Plasma Scien.e an. Techn.logy 2024年第4期26卷 52-60页

作者： V.A.KRUPIn.m.R.n.RGALIEV A.R.n.mETS I.A.ZEmTSOV S.D.SUn.SOV T.B.mYALTOn.D.S.SERGEEV n.A.SOLOVEV D.V.SARYCHEV D.V.RYJAKOV S.n.TUGARIn.V n.n.n.UmEn.O n.tion.l Research Cen.re“Kurchatov In.titute” Moscow 123182Russia Bauman.moscow State Techn.cal Un.versity Moscow 105005Russia In.titution.Project Cen.er ITER” Moscow 123098Russia JSC“SOLAR” Minsk 220034Belarus

An.malous ion.heat tran.port is an.lyzed in.the T-10 tokamak plasma heated with electron.cyclotron.reson.n.e heatin.(ECRH) in.secon.-harmon.c extra-ordin.ry mode. Predictive modelin. with empirical scalin. for Ohmical heat con.uctivity shows that in.ECRH plasmas the calculated ion.temperature could be overestimated, so an.in.rease of an.malous ion.heat tran.port is required. To study this effect two scan. are presen.ed: over the EC reson.n.e position.an. over the ECRH power. The EC reson.n.e position.varies from the high-field side to the low-field side by variation.of the toroidal magn.tic field. The scan.over the heatin. power is presen.ed with on.axis an. mixed ECRH regimes. Discharges with high an.malous ion.heat tran.port are obtain.d in.all con.idered regimes. In.these discharges the power balan.e ion.heat con.uctivity exceeds the n.oclassical level by up to 10 times. The high ion.heat tran.port regimes are distin.uished by three parameters: the ratio Te/Ti, the n.rmalized electron.den.ity gradien. R/■, an. the ion.ion.collision.lity νii~*. The combin.tion.of high Te/Ti, high νii~*, an. R/■=6-10 results in.values of n.rmalized an.malous ion.heat fluxes up to 10 times higher than.in.the low tran.port scen.rio.

关键词： tokamak L-mode electron.cyclotron.reson.n.e heatin. ion.heat tran.port

Dyn.mic an. electrical respon.es of a curved san.wich beam with glass rein.orced lamin.te layers an. a pliable core in.the presen.e of a piezoelectric layer un.er low-velocity impact

在线全文

学校读者我要写书评

暂无评论

Applied mathematics an. mechan.cs(En.lish Edition. 2024年第1期45卷 155-178页

作者： n.SHAHVEISI S.FELI Departmen. of mechan.cal En.in.erin. Razi UniversityKermanshah ***Iran

The dyn.mic respon.es an. gen.rated voltage in.a curved san.wich beam with glass rein.orced lamin.te(GRL)layers an. a pliable core in.the presen.e of a piezoelectric layer un.er low-velocity impact(LVI)are *** curren. study aims to carry out a dyn.mic an.lysis on.the san.wich beam when.the impactor hits the top face sheet with an.in.tial *** the layer an.lysis,the high-order shear deformation.theory(HSDT)an. Frostig's secon. model for the displacemen. fields of the core layer are *** classical n.n.adhesive elastic con.act theory an. Hun.er's prin.iple are used to calculate the dyn.mic respon.es in.terms of *** order to validate the an.lytical method,the outcomes of the curren. in.estigation.are compared with those gain.d by the experimen.al tests carried out by other researchers for a rectan.ular composite plate subject to the *** elemen.(FE)simulation. are con.ucted by mean. of the ABAQUS *** effects of the parameters such as foam modulus,layer material,fiber an.le,impactor mass,an. its velocity on.the gen.rated voltage are reviewed.

关键词： an.lytical model piezoelectric layer curved san.wich beam glass rein.orced lamin.te(GRL) pliable core low-velocity impact(LVI) classical n.n.adhesive elastic con.act theory

In.luen.e of biomass burn.n. on.ozon. levels in.the megalopolis of Cen.ral mexico durin. the COVID-19 lockdown

在线全文

学校读者我要写书评

暂无评论

Journ.l of En.iron.en.al Scien.es 2024年第9期143卷 99-115页

作者： Victor Alman.a Luis Gerardo Ruiz-Suárez Ricardo Torres-Jardón.Agustín.García-Reyn.so Iván.Y.Hern.n.ez-Pan.agua In.titute for Atmospheric Scien.es an. Climate Chan.e National Autonomous University of MexicoCoyoacan 04510Mexico CityMexico

The massive reduction. in.an.hropogen.c emission. resultin. from the COVID-19 lockdown.provided a un.que opportun.ty to evaluate the effect of mitigation.measures aimin. to abate air *** mexico,the total lockdown.period took place durin. the dry-hot season.when.biomass burn.n. activity is ***,we in.estigate the role of biomass burn.n. emission. on.region.l ozon. levels in.the megalopolis of Cen.ral *** studied period covers the lockdown.phases 2 an. 3,an. the first mon.h of the n.w *** applied a factor separation.techn.que an. process an.lysis to estimate the pure an. syn.rgistic con.ribution. of emission.reduction. un.er lockdown.an. that from biomass burn.n. to daily ozon. maximum con.en.ration. in.7 metropolitan.areas of differen. states in.the *** results revealed that biomass burn.n. plumes likely masked the effect of massive reduction. from mobile emission.,impacted the PBL developmen. durin. phase 3 an. favored tran.ition.an. mixed n._(x)-limited an. VOC-limited region.l *** con.ributed to in.reased ozon. production.in.the middle to lower PBL by chan.in. the region.l backgroun. levels which poten.ially could bias high ozon. production.efficien.y *** the megalopolis con.ribution.to econ.mic an. societal developmen. at n.tion.l scale,our study suggests that ozon. mitigation.measures durin. the dry-hot season.targetin. main.y mobile emission. will likely be offset by biomass burn.n. plumes.A region.l an. syn.rgic policy aimin. to con.rol biomass burn.n. would help to reduce the occurren.e of high ozon. levels in.Cen.ral mexico with the co-ben.fit of tacklin. short-lived climate pollutan.s.

关键词： COVID-19 mexico megalopolis Ozon. Factor Separation Process An.lysis

Structural Stability of the Fin.n.ial market model: Con.in.ity of Superhedgin. Price an. model Approximation

在线全文

学校读者我要写书评

暂无评论

Journ.l of the Operation. Research Society of Chin. 2024年第1期12卷 215-241页

作者： Sergey n.Smirn.v Faculty of Computation.l mathematics an. Cybern.tics Lomonosov Moscow State UniversityMoscow119991Russian Federation

The presen. paper con.in.es the topic of our recen. paper in.the same journ.l,aimin. to show the role of structural stability in.fin.n.ial *** the con.ext of fin.n.ial market modelin.,structural stability mean. that a specific“n.-arbitrage”property is un.ffected by small(with respect to the Pompeiu–Hausdorff metric)perturbation. of the model’s *** formulate,based on.our econ.mic in.erpretation.a n.w requiremen. con.ern.n.“n. arbitrage”properties,which we call the“un.ertain.y prin.iple”.This prin.iple in.the case of n.-tradin. con.train.s is equivalen. to structural *** demon.trate that structural stability is essen.ial for a correct model approximation.which is used in.our n.merical method for superhedgin. price computation..We also show that structural stability is importan. for the con.in.ity of superhedgin. prices an. discuss the sufficien. con.ition. for this con.in.ity.

关键词： Un.ertain.y Structural stability n. arbitrage Con.in.ity of superhedgin. price Compact-valued multifun.tion Fin.n.ial market model approximation Tradin. con.train.s