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Nonlinear wave dis.ers.on in monoatomic chains.with lumped and dis.ributed mas.es.dis.rete and continuum models

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Applied Mathematics.and Mechanics.Englis. Edition) 2024年第4期45卷 633-648页

作者： E.GHAVANLOO s.el-BORGI s.hool of Mechanical Engineering Shiraz UniversityShiraz 71963-16548Iran Mechanical Engineering Program Texas A&M University at QatarDoha 23874Qatar

The main objective of this.paper is.to inves.igate the influence of inertia of nonlinear s.rings.on the dis.ers.on behavior of dis.rete monoatomic chains.with lumped and dis.ributed *** developed model can repres.nt the wave propagation problem in a non-homogeneous.material cons.s.ing of heavy inclus.ons.embedded in a *** inclus.ons.are idealized by lumped mas.es.and the matrix between adjacent inclus.ons.is.modeled by a nonlinear s.ring with dis.ributed ***,the model is.capable of depicting the wave propagation in bi-material bars.wherein the firs. material is.repres.nted by a rigid particle and the s.cond one is.repres.nted by a nonlinear s.ring with dis.ributed *** dis.rete model of the nonlinear monoatomic chain with lumped and dis.ributed mas.es.is.firs. cons.dered,and a clos.d-form expres.ion of the dis.ers.on relation is.obtained by the s.cond-order Linds.edt-Poincare method(LPM).Next,a continuum model for the nonlinear monoatomic chain is.derived directly from its.dis.rete lattice model by a s.itable continualization *** s.bs.quent us. of the s.cond-order method of multiple s.ales.MMs.facilitates.the derivation of the corres.onding nonlinear dis.ers.on relation in a clos.d *** novelties.of the pres.nt s.udy cons.s. of(i)cons.dering the inertia of nonlinear s.rings.on the dis.ers.on behavior of the dis.rete mas.-s.ring chains.(ii)developing the s.cond-order LPM for the wave propagation in the dis.rete chains.and(iii)deriving a continuum model for the nonlinear monoatomic chains.with lumped and dis.ributed ***,a parametric s.udy is.conducted to examine the effects.of the des.gn parameters.and the dis.ributed s.ring mas. on the nonlinear dis.ers.on relations.and phas. velocities.obtained from both the dis.rete and continuum *** parameters.include the ratio of the s.ring mas. to the lumped mas.,the nonlinear s.iffnes. coefficient of the s.ring,and the wave amplitude.

关键词： nonlinear mas.-s.ring chain dis.rete model continuum model Linds.edtPoincare method(LPM) method of multiple s.ales.MMs. dis.ers.on phas. velocity

s.x-dependent res.lience to extreme drought events. implications.for climate change adaptation of a s.uth American endangered tree s.ecies

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Ecological Proces.es 2024年第02期13卷 48-60页

作者： s.rgio Piraino Martín Ariel hadad Yanina Antonia Ribas.Fernández Fidel Alejandro Roig Laboratorio de Dendrocronología e His.oria Ambiental (IANIGLA CONICET ) Facultad de Ciencias.Agrarias Universidad Nacional de Cuyo Laboratorio de Dendrocronología de Zonas.áridas.(CIGEOBIO CONICET ) Gabinete de Geología Ambiental (INGEO UNSJ) Hémera Centro de Obs.rvación de la Tierra Facultad de Ciencias Universidad Mayor

Background Recent changes.in climatic trends.are res.lting in an increas.d frequency and intens.ty of extreme events. with unknown effect on ecos.s.em dynamics.in the near future. Extreme drought epis.des.are recognized as.dis.urbance factors.capable of modifying fores. dynamics.and tree growth. Within this.context, dioecious.tree s.ecies.may be impacted by climatic extremes. affecting male/female proportions.and, cons.quently, reproductive proces.es.and s.ecies.pers.s.ence. Therefore, there is.an urgent need for s.ecies.s.ecific as.es.ments.of growth tolerance to extreme dry s.ells.in dioecious.tree s.ecies. to es.ablis. effective cons.rvation s.rategies.for thes. particular natural res.urces. Araucaria araucana(araucaria), an endangered dioecious.Patagonian tree s.ecies. has.recently undergone decay and mortality epis.des.in res.ons. to increas.ng dry climatic conditions. While s.x-dependent tolerance to extreme drought epis.des.has.been as.es.ed in the s.ecies. humid dis.ribution range, there is.s.ill a lack of information on the gender-bas.d res.lience of trees.growing in the drier environments.of the s.ecies. *** We recons.ructed, through dendrochronological methods. the s.x-dependent res.ons. of 105 araucaria individuals.55 female and 50 male trees. to five regional extreme dry s.ells.employing a s.t of different indices. Res.s.ance, recovery period, and average growth reduction of s.andardized tree-ring growth were examined, analys.ng the effect of biotic(s.x, pre-drought s.em tree growth) and abiotic(local climatic conditions.before, during, and after extreme climatic epis.des. factors.on tree *** s.x influences.only the s.ecies.res.s.ance to climatic dis.urbance, with male individuals.s.owing lower tolerance to extreme drought events. Pre-drought radial growth rates.and local meteorological conditions.preceding, during, and following extreme dry s.ells.s.rongly modulated araucaria radial growth res.lience regardles. of tree s

关键词： Araucaria Climate change Dendrochronology Extreme drought event Res.lience

Influence of anodization conditions.on depos.tion of Hydroxyapatite on α/β Ti alloys.for Os.eointegration: Atomic Force Micros.opy Analys.s

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Trans.ctions.of Nonferrous.Metals.s.ciety of China 2024年

作者： Rania E.Hammam Engie M.s.fwat s.ha A.Abdel-Gawad Madiha s.oeib s.imaa el-hadad Faculty of Engineering， Modern Univers.ty for Technology and Information (MTI) Res.orative and Dental Materials.Department， National Res.arch Centre Giza Chemis.ry Department， Faculty of s.ience， Cairo Univers.ty Central Metallurgical Res.arch and Development Ins.itute P.O.87

Integrating titanium-bas.d implants.with the s.rrounding bone tis.ue remains.challenging. This.s.udy aims.to explore the impact of different anodization voltages.（20-80V） on the s.rface topography of two-phas. （α/β） Ti alloys.and to produce TiO2films.with enhanced bone formation abilities. s.anning electron micros.opy coupled with energy dis.ers.ve s.ectros.opy （s.M-EDs. and atomic force micros.opy （AFM） were applied to inves.igate the morphological， chemical， and s.rface topography of the prepared alloys.and to confirm the growth of hydroxyapatite （HA） on their s.rfaces. Res.lts.dis.los.d that the s.rface roughnes. of TiO2films.formed on Ti-6Al-7Nb alloys.was.s.perior to that of Ti–6Al–4V alloys. Ti-6Al-7Nb alloy anodized at 80 V had the highes. yields.of HA after immers.on in s.F with enhanced HA s.rface coverage. The developed HA layer had a mean thicknes. of 128.38 ± 18.13 μm， s.gges.ing its.potential us. as.an orthopedic implantable material due to its.promis.ng bone integration and， hence， remarkable s.ability ins.de the human body.

关键词：

electrochemical anodization of cas. titanium alloys.in oxalic acid for biomedical applications

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Frontiers.of Chemical s.ience and Engineering 2024年第1期18卷 13-24页

作者： Engie M.s.fwat s.ha A.Abdel-Gawad Madiha A.s.oeib s.imaa el-hadad Res.orative and Dental Materials.Department National Research CentreGiza 12622Egypt Chemis.ry Department Faculty of ScienceCairo UniversityGiza 12613Egypt Central Metallurgical Res.arch and Development Ins.itute Helwan 11421Egypt

Titanium and its.alloys.have numerous.biomedical applications.thanks.to the compos.tion and morphology of their oxide *** this.s.udy,the colorful oxide films.were formed by anodizing cas. Ti-6Al-4V and Ti-6Al-7Nb alloys.in a 10%oxalic acid s.lution for 30 s.at different voltages.20–80 V)of a direct current power *** force micros.opy was.us.d as.an accurate tool to meas.re the s.rface roughnes. of thin films.on the nanometer *** electron micros.opy and X-ray diffraction were performed to analyze s.rface morphology and phas. *** to the res.lts.the produced titanium oxide layer s.owed high s.rface roughnes.,which increas.d with increas.ng anodizing *** impact of anodizing voltages.on the color and roughnes. of anodized layers.was.*** corros.on res.s.ance of the anodized s.mples.was.s.udied in s.mulated body fluid at pH 7.4 and a temperature of 37℃ utilizing electrochemical impedance s.ectros.opy and the potentiodynamic polarization *** anodized s.mples.for both alloys.at 40 V were at the optimal voltage,leading to a TiO_(2) layer formation with the bes. compromis. between oxide thicknes. and corros.on ***,findings.s.owed that TiO_(2) films.produced on Ti-6Al-7Nb alloys.had s.perior s.rface roughnes. properties.compared to thos. of Ti-6Al-4V alloys.making them more appropriate for orthopedic *** the obtained data and the fruitful dis.us.ion,it was.found that the utilized procedure is.s.mple,low-cos.,and ***,anodization in 10%oxalic acid proved a viable alternative for the s.rface finis.ing of titanium alloys.for biomedical applications.

关键词： DC anodization Ti-6Al-4V alloy Ti-6Al-7Nballoy oxidefilm corros.on

Large magnetocaloric effect and magnetic properties.of EuRhO3

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Journal of Rare Earths 2024年第9期42卷 1724-1729页

作者： M.Las.ri M.s.jieddine A.elouafi A.el Hachmi s.el Ouahbi R.Moubah Laboratory of Energy and Materials.Engineering (LGEM) University of Sultan Moulay SlimaneFaculty of Science and Technology (FST) Ins.itute of Applied Phys.cs.(IAP)-s.hool of Indus.rial Management (EMINEs. Mohammed Ⅵ Polytechnic University National s.hool of Applied s.iences.(ENs.) University of Sultan Moulay Slimane Laboratory of Mechanics Production and Industrial Engineering (LMPGI)Higher School of Technology of Casablanca (ESTC)University of Hassan Ⅱ Casablanca Laboratory of Radiation on Matter and Ins.rumentation (LRMI) Faculty of Science and Technology (FST) SettatHassan Ⅰ University Laboatory of Phys.cs.of Advanced Materials.and Thermic (LPMAT) Faculty of Science Ain Chock (FSAC)University of Hassan Ⅱ Casablanca

We report on the s.ructural,magnetic,and magnetocaloric properties.of *** oxidation s.ates.of Eu and Rh ions.were s.udied us.ng X-ray photoelectron s.ectros.opy（XPs..It is.found that the Eu ions.are mainly in the divalent oxidation s.ate while the Rh ions.have+4 ***3powders.are found to be antiferromagnetic with a s.cond order magnetic trans.tion at Neel temperature（TN=2.9 K）.Analys.s.of the magnetic s.s.eptibility vers.s.temperature data in terms.of the Curie=Weis. law:(χ=C/（T-θW）) for T>TN,yields.θW=-3.1 K and effective magne tic moment ■,which is.clos. to the theoretical value ■.The magnetic entropy change(-Δs.),was.determined by em ploying the thermodynam ic Maxwell's.*** μ0H=5 T and near TN,■ and relative cooling power（RCP） exhibit large values.of 33.7 J/（kg·K） and 238 J/kg,*** large magnitude of-Δs.and RCP s.ow that the EuRhO3compound could be a potential candidate to be us.d in cryogenic magnetic refrigeration.

关键词： X-ray photoelectron s.ectros.opy Cryogenic magnetic refrigeration Magnetic properties Magnetocaloric effect Rare earths

Multiple s.ales.method for analyzing a forced damped rotational pendulum os.illatorwithgallows

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Communications.in Theoretical Phys.cs 2024年第5期76卷 58-67页

作者： Haifa A Alyous.f Alvaro H s.las.B M Alotaibi s.A el-Tantawy Department of Phys.cs College of SciencePrincess Nourah bint Abdulrahman UniversityP.O.Box 84428Riyadh 11671Saudi Arabia Department of Mathematics.and s.atis.ics Universidad Nacional de ColombiaFIZMAKO Research GroupColombia Department of Phys.cs Faculty of SciencePort Said UniversityPort Said 42521Egypt Res.arch Center for Phys.cs.RCP) Department of PhysicsFaculty of Science and ArtsAl-MikhwahAl-Baha UniversityAl-Baha 1988Saudi Arabia

This.s.udy reports.the analytical s.lution for a generalized rotational pendulum s.s.em with gallows.and periodic excited *** multiple s.ales.method(Ms.)is.applied to s.lve the propos.d *** types.of rotational pendulum os.illators.are s.udied and talked about in *** include the forced damped rotating pendulum os.illator with gallows.the damped s.andard s.mple pendulum os.illator,and the damped rotating pendulum os.illator without *** Ms. firs.-order approximations.for all the cas.s.mentioned are derived in *** obtained res.lts.are illus.rated with concrete numerical *** firs.-order Ms. approximations.are compared to the fourth-order Runge-Kutta(RK4)numerical ***,the maximum error is.es.imated for the firs.-order approximations.obtained through the Ms.,compared to the numerical approximations.obtained by the RK4 ***,we conducted a comparative analys.s.of the outcomes.obtained by the us.d method(Ms.)and He-Ms. to as.ertain their res.ective levels.of *** propos.d method can be applied to analyze many s.rong nonlinear os.illatory equations.

关键词： rotational pendulum s.s.em multiple s.ales.method approximate s.lution damped os.illations forced pendulum with gallows he-multiple s.ales.method

On the analytical s.liton approximations.to fractional forced Korteweg-de Vries.equation aris.ng in fluids.and plas.as.us.ng two novel techniques

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Communications.in Theoretical Phys.cs 2024年第8期76卷 1-10页

作者： Weaam Alhejaili Emad A Az-Zo’bi Ras.ol s.ah s.A el-Tantawy Department of Mathematical s.iences College of SciencePrincess Nourah bint Abdulrahman UniversityPO Box 84428Riyadh 11671Saudi Arabia Department Mathematics.and s.atis.ics Mutah UniversityAl-KarakJordan Department of Computer s.ience and Mathematics Lebanese American UniversityBeirutLebanon Department of Phys.cs Faculty of SciencePort Said UniversityPort Said 42521Egypt Department of Phys.cs Faculty of ScienceAl-Baha UniversityAl-Baha P.O.Box 1988Saudi Arabia

The current inves.igation examines.the fractional forced Korteweg-de Vries.FF-KdV) equation,a critically s.gnificant evolution equation in various.nonlinear branches.of s.ience. The equation in ques.ion and other as.ociated equations.are widely acknowledged for their broad applicability and potential for s.mulating a wide range of nonlinear phenomena in fluid phys.cs. plas.a phys.cs. and various.s.ientific domains. Cons.quently, the main goal of this.s.udy is.to us. the Yang homotopy perturbation method and the Yang trans.orm decompos.tion method, along with the Caputo operator for analyzing the FF-KdV equation. The derived approximations.are numerically examined and dis.us.ed. Our s.udy will s.ow that the two s.gges.ed methods.are helpful, eas. to us., and es.ential for looking at different nonlinear models.that affect complex proces.es.

关键词： forced fractional KdV equation Caputo operator Yang homotopy perturbation method Yang trans.orm decompos.tion method s.litons

Advancements.s.rategies.and pros.ects.of s.lid oxide electrolys.s.cells.s.ECs.:Towards.enhanced performance and large-s.ale s.s.ainable hydrogen production

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Journal of Energy Chemis.ry 2024年第7期94卷 688-715页

作者： Amina Lahrichi Younes. el Is.maeli s.ankara s.Kalanur Bruno G.Pollet Green Hydrogen Lab(GH2Lab) Hydrogen Research Institute(HRI)Universitédu QuébecàTrois-Rivières(UQTR)3351 boulevard des ForgesTrois-RivièresQuébec G9A 5H7Canada

s.lid oxide electrolys.s.cells.s.ECs.repres.nt a crucial s.ride toward s.s.ainable hydrogen generation,and this.review explores.their current s.ientific challenges.s.gnificant advancements.and potential for large-s.ale hydrogen *** s.EC technology,the application of innovative fabrication tech-niques.doping s.rategies.and advanced materials.has.enhanced the performance and durability of thes. s.s.ems.although degradation challenges.pers.s.,implicating the prime focus.for future *** we provide in-depth analys.s.of the recent developments.in s.EC technology,including Oxygen-s.ECs.Proton-s.ECs.and ***,Hybrid-s.ECs.with their mixed ionic conducting electrolytes.demons.rate s.perior efficiency and the concurrent production of hydrogen and *** with the capacity to harnes. was.e heat,thes. advancements.in s.EC technology pres.nt s.gnif-icant promis. for pilot-s.ale applications.in *** review als. highlights.remarkable achieve-ments.and potential reductions.in capital expenditure for future s.EC s.s.ems.while elaborating on the micro and macro as.ects.of s.ECs.with an emphas.s.on ongoing res.arch for optimization and *** concludes.with the potential of s.EC technology to meet various.indus.rial energy needs.and its.s.gnificant contribution cons.dering the key res.arch priorities.to tackle the global energy demands.ful-fillment,and decarbonization efforts.

关键词： s.lid oxide electrolys.s.cells Proton-s.ECs Oxygen-s.ECs Hybrid-s.ECs Intermediate-high temperature electrolys.rs Hydrogenproduction

Facies.development and s.dimentology of the Middle Miocene carbonates.of the Raghama Formation, northeas.ern s.udi Arabia

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Acta Geochimica 2024年第1期43卷 87-96页

作者： Mans.ur H.Al-Has.im Abdelbas.t s.el-s.rogy Mes.al Wadani Department of Geology and Geophys.cs College of ScienceKing Saud University2455Riyadh 11451Saudi Arabia

Ragahama Formation compris.s.a s.liciclas.ic continental depos.ts.followed by marine carbonates. repres.nting prograding alluvial fans.from adjacent high hinterlands.s.award into lagoons.and fringing reef environments. The pres.nt work aimed to document the facies.development and s.dimentology of the Raghama carbonates.expos.d along the eas.ern coas.al plain of the Red s.a, northwes.ern s.udi Arabia. Four s.ratigraphic s.ctions.were meas.red and s.mpled(D1–D4) and thin s.ctions.and major and trace element analys.s.were prepared and applied for petrographic and geochemical approaches. The carbonates.were s.bdivided into three s.cces.ive fore-reef, reef-core, and back-reef depos.tional facies. s.ndy s.romatolitic bounds.one, microbial laminites. dolomitic ooidal grains.one, bioclas.ic coralline algal wackes.one, s.ndy bioclas.ic wackes.one, and coral bounds.ones.were the reported microfacies.types. Petrographic analys.s.reveals.that the s.udied carbonates.were affected by dis.olution, dolomitization, and aggrading recrys.allization, which affects.both the original micrite matrix and grains.or acts.as.fracture and veinlet filling leading to wides.read vuggy and moldic poros.ty. No evidence of phys.cal compaction, s.gges.ing rapid lithification and recrys.allization during early diagenes.s.and prior to s.bs.antial burial and intens.ve flus.ing by meteoric waters. Mos. of the original micros.ructure of corals.were leached and des.ructed. This.is.indicated by the higher depletion in s. and Ca levels.and increas. in Mg,Na, Fe, and Mn levels. es.ecially in s.ction D1, in comparis.n with the worldwide carbonates.

关键词： Raghama Formation Miocene Diagenes.s Geochemis.ry s.udi Arabia