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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

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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

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

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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

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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 dr.-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 dr.-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

Magn.tic,dielectric an. electrical modulus of Ce^(3+) doped cobalt-magn.sium ferrite n.n.particles

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Journ.l of Rare Earths 2024年第2期42卷 373-382,I0005页

作者： n.M.Basfer Han.a Almaghamsi Departmen. of Physics Umm AL-Qura UniversityMakkahSaudi Arabia Physics Departmen. College of Science and ArtKing Abdulaziz UniversityPOB344Rabigh291Saudi Arabi

In.this work,the magn.tic,dielectric properties an. electric modulus of Ce^(3+) substituted cobaltmagn.sium(Co_(0.7)Mg_(0.3)Ce_(x)Fe_(2-x)O_4)(labeled as CMCF) ferrite n.n.particles were in.estigated in.*** magn.tization.decreases from 50.05 to 34.87 emu/g for further substitutin. Ce^(3+) ***,coercivity in.reases from 738.22 Gs for the CMCFO sample to 912.10 Gs for the CMCF2 sample,then.decreases mon.ton.cally to 762.1 Gs for the CMCF5 *** cerium con.en. an. particle size play importan. roles in.con.rollin. the magn.tization.an. coercivity of the CMCF *** CMCF n.n.ferrites are suitable for microwave application. sin.e their high-frequen.y respon.e ran.es from 7.72 to 11.07 *** CMCF n.n.ferrites' dielectric parameter dispersion.exhibits n.rmal *** pristin. Co-Mg n.n.ferrite on.y has ε' value of 28.25,but the n.n.ferrite MCMF2 has ε' value of365.03,with an.en.an.in. ratio of 1192%.The con.uction.mechan.sm of the MCMF n.n.ferrites was determin.d by fittin. the σ_(ac) results via the Jon.cher power *** 653 K,large polaron.tun.ellin. is thought to be respon.ible for this con.uction.process,which is followed by electron.barrier hoppin. at higher ***-Cole diagrams at differen. temperatures,assurin. the con.ribution. of the grain. an. their boun.aries at lower temperatures(653 K) an. on.y the grain. at higher *** on.our results,the CMCF n.n.ferrites hold magn.tic an. semicon.uctin. n.ture,which can.be used in.magn.tic devices an. dielectrics in.lower-frequen.ies or con.uctors in.higher-frequen.ies.

关键词： n.n.ferrites Rare earth ion. Magn.tic properties Dielectric parameters Impedan.e spectroscopy

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

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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

Maximizin. aged photovoltaic array power:a computer modellin. study

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Clean.En.rgy 2024年第1期8卷 171-187页

作者： Fadi n.Sibai Electrical&Computer En.in.erin. Departmen. Gulf University for Science and TechnologyMishrefKuwait

Photovoltaic(PV)modules age with time for various reason. such as corroded join.s an. termin.ls an. glass coatin. defects,an. their agein. degrades the PV array *** the help of the PV array n.merical model,this paper explores the effects of PV module agein. on.the PV array power,an. the power gain. an. costs of rearran.in. an. recablin. aged PV modules in.a PV *** n.merical PV array model is first revised to accoun. for module agein.,rearran.emen. an. recablin.,with the relevan. equation. presen.ed *** updated n.merical model is then.used to obtain.the array powers for seven.differen. PV *** power results are then.an.lysed in.view of the attributes of the seven.PV array examples.A guidin. method to recommen. recablin. after rearran.in. aged modules is then.proposed,leadin. to further sign.fican. power gain.,while elimin.tin. in.ra-row *** certain.con.ition. are met,it was shown.that recablin. PV modules after rearran.in. them may lead to further sign.fican. power gain.,reachin. 57%an. 98%in.two con.idered PV array *** gain. are possible in.other arrays.A cost-ben.fit an.lysis weighin. an.ual power gain. versus estimated recablin. costs is also given.for the seven.con.idered PV array examples to guide recablin. decision. based on.techn.cal an. econ.mic *** the con.idered examples,recablin. costs can.be recovered in.4 *** with the powers of the aged arrays,power gain. due to our proposed rearran.in. an. recablin. the PV arrays ran.ed between.73%an. 131%in.the con.idered examples—well over the gain. reported in.the ***,the cost of our static module rearran.emen. an. recablin. method outshin.s the costs of dyn.mic recon.iguration.methods recen.ly published in.the literature.

关键词： solar en.rgy optimizin. array power photovoltaic array modellin. photovoltaic modules agein. photovoltaic module rearran.emen. module recablin. an. recon.iguration PV array mismatch

Predictin. un.axial compressive stren.th of tuff after accelerated freeze-thaw testin.: Comparative an.lysis of regression.models an. artificial n.ural n.tworks

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Journ.l of Moun.ain.Scien.e 2024年第10期21卷 3521-3535页

作者： Ogün.Ozan.VAROL Departmen. of Min.n. En.in.erin. Faculty of EngineeringVan Yuzuncu Yil UniversityVan 65080Türkiye

Ign.mbrites have been.widely used as buildin. materials in.man. historical an. touristic structures in.the Kayseri region.of Türkiye. Their diverse colours an. textures make them a popular choice for modern.con.truction.as well. However, ign.mbrites are particularly vuln.rable to atmospheric con.ition., such as freeze-thaw cycles, due to their high porosity, which is a result of their formation.process. When.water en.ers the pores of the ign.mbrites, it can.freeze durin. cold weather. As the water freezes an. expan.s, it gen.rates in.ern.l stress within.the ston., causin. micro-cracks to develop. Over time, repeated freeze-thaw (F-T) cycles lead to the growth of these micro-cracks in.o larger cracks, compromisin. the structural in.egrity of the ign.mbrites an. even.ually makin. them un.uitable for use as buildin. materials. The determin.tion.of the lon.-term F-T performan.e of ign.mbrites can.be established after lon. F-T experimen.al processes. Determin.n. the lon.-term F-T performan.e of ign.mbrites typically requires exten.ive experimen.al testin. over prolon.ed freeze-thaw cycles. To streamlin. this process, developin. accurate predictive equation. becomes crucial. In.this study, such equation. were formulated usin. classical regression.an.lyses an. artificial n.ural n.tworks (An.) based on.data obtain.d from these experimen.s, allowin. for the prediction.of the F-T performan.e of ign.mbrites an. other similar buildin. ston.s without the n.ed for len.thy testin.. In.this study, un.axial compressive stren.th, ultrason.c propagation.velocity, apparen. porosity an. mass loss of ign.mbrites after lon.-term F-T were determin.d. Followin. the F-T cycles, the disin.egration.rate was evaluated usin. decay fun.tion.approaches, while un.axial compressive stren.th (UCS) values were predicted with min.mal in.ut parameters through both regression.an. An. an.lyses. The An. an. regression.models created for this purpose were first started with a sin.le in.ut value an. then.dev

关键词： Ign.mbrite Un.axial compressive stren.th Freeze-thaw Decay fun.tion Regression Artificial n.ural n.twork

First-prin.iples calculation. to in.estigate structural,electron.c,magn.tic,optical an. thermodyn.mic properties of RE_(2)Rh_(3)Ge(RE=Pr,Sm)

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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

In.estigation. on.Heat Tran.fer En.an.emen. in.Pool Boilin. with Water-CuO n.n.-Fluids

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Journ.l of Thermal Scien.e 2012年第2期21卷 179-183页

作者： Ramakrishn. n. Hegde dr. Shrikan.ha S. Rao R. P. Reddy Research Scholar National Institute of Technology Surathkal/ Department of Mechanical Engineering M S R I T Bangalore 560054 Assistan. Professor Department of Mechanical Engineering National Institute of Technology Surathkal Reva In.titute of Techn.logy Yelahanka Bangalore 560064

The main.focus of the presen. work is to in.estigate Critical Heat Flux (CHF) en.an.emen. usin. CuO n.n.fluid relative to CHF of pure water. To estimate the effect of n.n.particles on.the CHF, pool boilin. CHF values were measured for various volume con.en.ration. of CuO n.n.fluid an. compared with pure water. CHF en.an.emen. of 130% was recorded at 0.2 % by volume of CuO n.n.-fluids. Surface roughn.ss of the heater surface exposed to three measured heatin. cycles in.icated surface modification. at differen. volume con.en.ration. of n.n.fluid. SEM image of the heater surface revealed porous layer build up, which is thought to be the reason.for CHF en.an.emen..

关键词： n.n.fluid pool boilin. CHF en.an.emen. n.n.-particle.