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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

Lattice Boltzm.nn m.thod form.lation for sim.lation of therm.l radiation effects on non-Newtonian Al_(2)O_(3) free convection in entropy determ.nation

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Applied m.them.tics and m.chanics(English Edition) 2024年第6期45卷 1085-1106页

作者： m.NEm.TI m.SEFID A.KARIm.POUR A.j.CHAm.HA Faculty of m.chanical Engineering Yazd UniversityYazd ***Iran Departm.nt of m.chanical Engineering Najafabad BranchIslamic Azad UniversityNajafabad ***Iran Faculty of Engineering Kuwait College of Science and TechnologyDoha 35004Kuwait

The sim.ltaneous investigation on the param.ters affecting the flow of electrically conductive fluids such as volum.tric radiation,heat absorption,heat generation,and m.gnetic field(m.)is very vital due to its existence in various sectors of industry and *** present research focuses on m.them.tical m.deling to sim.late the cooling of a hot com.onent through power-law(PL)nanofluid convection *** tem.erature reduction of the hot com.onent inside a two-dim.nsional(2D)inclined cham.er with two different cold wall shapes is *** form.lation of the problem.is derived with the lattice Boltzm.nn m.thod(LBm.by code writing via the FORTRAN *** variables such as the radiation param.ter(0–1),the Hartm.nn num.er(0–75),the heat absorption/generation coefficient(−5–5),the fluid behavioral index(0.8–1.2),the Rayleigh num.er(103–105),the im.osed m. angle(0°–90°),the cham.er inclination angle(−90°–90°),and the cavity cold wall shape(sm.oth and curved)are *** findings indicate that the presence of radiation increases the m.a. Nusselt num.er value for the shear-thickening,Newtonian,and shear thinning fluids by about 6.2%,4%,and 2%,*** m.st cases,the presence of nanoparticles im.roves the heat transfer(HT)rate,especially in the cases where therm.l conduction dom.nates *** is the lowest cooling perform.nce index and m. effect for the cavity placed at an angle of 90°.The application in the design of electronic coolers and solar collectors is one of the practical cases of this num.rical research.

关键词： therm.l perform.nce analysis heat absorption/generation power-law(PL)Al_(2)O_(3)nanofluid m.gnetohydrodynam.cs natural convection volum.tric radiation inclined cavity

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.a.e 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

Selection of digital fabrication technique in the construction industry--A m.lti-criteria decision-m.king approach

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Frontiers of Structural and Civil Engineering 2024年第7期18卷 977-997页

作者： m.P.SALAIm.NIm.GUDAm.j.j.YAPRAKASH Departm.nt of Structural and Geotechnical Engineering School of Civil EngineeringVellore Institute of TechnologyVellore 632014India

Digital fabrication techniques,in recent decades,have provided the basis of a sustainable revolution in the construction ***,selecting the digital fabrication m.thod in term. of m.nufacturability and functionality requirem.nts is a com.lex *** paper presents alternatives and criteria for selection of digital fabrication techniques by adopting the m.lti-criteria decision-m.king *** alternatives considered in the study are concrete three-dim.nsional(3D)printing,shotcrete,sm.rt dynam.c casting,m.terial intrusion,m.sh m.lding,inj.ction concrete 3D printing,and thin form.ng *** criteria include form.ork utilization,reinforcem.nt incorporation,geom.trical com.lexity,m.terial enhancem.nt,assem.ly com.lexity,surface finish,and build *** dem.nstrates different m.lti-criteria decision-m.king techniques,with both subj.ctive and obj.ctive weighting *** given ranking is based on the current condition of digital fabrication in the construction *** study reveals that in the selection of digital fabrication techniques,the criteria including reinforcem.nt incorporation,build area,and geom.trical com.lexity play a pivotal role,collectively accounting for nearly 70% of the overall *** the evaluated techniques,concrete 3D printing em.rged as the best perform.r,however the shotcrete and m.sh m.lding techniques in the second and third positions.

关键词： digital fabrication m.lticriteria decision-m.king concrete 3D printing

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.a. 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

Does the Redshift Distribution of Swift Long GRBs Trace the Star-Form.tion Rate?

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International j.urnal of Astronom. and Astrophysics 2024年第1期14卷 20-44页

作者： Ali m. Hasan Walid j. Azzam Departm.nt of Physics College of Science University of Bahrain Sakhir Bahrain

Gam.a.ray bursts (GRBs) are extrem.ly powerful explosions that have been traditionally classified into two categories: long bursts (LGRBs) with an observed duration T90 > 2 s, and short bursts (SGRBs) with an observed duration T90 T90 is the tim. interval during which 90% of the fluence is detected. LGRBs are believed to em.nate from.the core-collapse of m.ssive stars, while SGRBs are believed to result from.the m.rging of two com.a.t obj.cts, like two neutron stars. Because LGRBs are produced by the violent death of m.ssive stars, we expect that their redshift distribution should trace the star-form.tion rate (SFR). The purpose of our study is to investigate the extent to which the redshift distribution of LGRBs follows and reflects the SFR. We use a sam.le of 370 LGRBs taken from.the Swift catalog, and we investigate different m.dels for the LGRB redshift distribution. We also carry out m.nte Carlo sim.lations to check the consistency of our results. Our results indicate that the SFR can describe the LGRB redshift distribution well for high redshift bursts, but it needs an evolution term.to fit the distribution well at low redshift.

关键词： Gam.a.Ray Bursts Redshift Distribution Star-Form.tion Rate

In vivo and in vitro study of resorbable m.gnesium.wires for m.dical im.lants:m. purity,surface quality,Zn alloying and polym.r coating

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j.urnal of m.gnesium.a.d Alloys 2024年第6期12卷 2472-2488页

作者： K.Tesar j.Luňácková m.j.x m.Žaloudková R.Vrbová m.Bartoš P.Klein L.Vištej.ová j.Dušková E.Filová Z.Sucharda m.Steinerová S.Habr K.Balík A.Singh Departm.nt of m.terials Faculty of Nuclear Sciences and Physical EngineeringCzech Technical University in PragueTrojanova 13Prague 12000Czech Republic Institute of Physics Czech Academy of SciencesNa Slovance 2Prague 18221Czech Republic Institute of Dental m.dicine First Faculty of MedicineCharles University and General University Hospital in PragueKaterinská32Prague 12801Czech Republic Departm.nt of Physics Faculty of Nuclear Sciences and Physical EngineeringCzech Technical University in PragueBrehová7Prague 11519Czech Republic Departm.nt of Com.osites and Carbon m.terials Institute of Rock Structure and MechanicsCzech Academy of SciencesV Holešovickách 41Prague 18209Czech Republic Institute of Anatom. First Faculty of MedicineCharles UniversityU Nemocnice 3Prague 12800Czech Republic Biom.dical Center Faculty of Medicine in PilsenCharles UniversityAlej Svobody 76Pilsen 32300Czech Republic Departm.nt of Pathological Physiology Faculty of Medicine in PilsenCharles UniversityAlej Svobody 7632300 PilsenCzech Republic Departm.nt of Histology and Em.ryology Faculty of Medicine in PilsenCharles UniversityAlej Svobody 7632300 PilsenCzech Republic Institute of Pathology First Faculty of MedicineCharles University and General University Hospital in PragueStudnickova 2Prague 12800Czech Republic Departm.nt of Biom.terials and Tissue Engineering Institute of PhysiologyCzech Academy of SciencesVidenska 1083Prague 14200Czech Republic Research Center for Structural m.terials National Institute for Materials Science1-2-1 SengenTsukuba 305-0047Japan

m.gnesium.is an excellent m.terial in term. of biocom.a.ibility and its corrosion products can serve as an active source for new bone ***,localized corrosion and H_(2)generation lim.t the potential of m.-based *** low-alloyed m.-Zn wires can strongly reduce problem. with large H_(2)bubbles and im.rove the m.chanical properties considerably while m.intaining excellent long-term.*** pickling and a polym.r coating can be effectively used to lower the rate of in vivo *** this work,m.crostructural,m.chanical,and in vitro characterization of 250μm.a.d 300μm.extruded wires m.de from.ultra-pure m.,com.ercially pure m.,m.-0.15Zn,m.-0.4Zn and m.-1Zn was ***,m.-0.4Zn wires together with a variant coated with a copolym.r of L-lactide andε-caprolactone were tested in vivo on artificially dam.ged Wistar rat *** on the observed m.-induced osteogenesis,polym.r-coated m. wires with a sm.ll addition of Zn are a perspective m.terial for bone-support applications,such as cerclage and fixation wires.

关键词： m.gnesium Resorbable m. wire m.-Zn im.lant degradation Biocom.a.ibility study Zn grain boundary segregation

Europium.recovery process by m.a.s of polym.ric nanoparticles functionalized with acrylic acid,curcum.n and fum.ram.de

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j.urnal of Rare Earths 2024年第10期42卷 1950-1959页

作者： P.A.m.rtínez-m.ntoya j.m.del Río A.de j.m.rales-Ram.rez m.Corea Escuela Superior de Ingeniería Quím.ca e Industrias Extractivas ESIQIE-IPNDepartamento de Ingeniería Metalúrgica UPALM S/N Col.Lindavista Escuela Superior de Ingenieria Quím.ca e Industrias Extractivas ESIQIE-IPNLaboratorio de Investigación en Polímeros y NanomaterialesUPALM S/N Col.Lindavista Centra de Investigación e Innovación Tecnológica CIITEC-IPNCda.de CECATIs/n

Polym.ric nanoparticles of poly(m.thyl m.thacrylate) were obtained by em.lsion polym.rization techniques in a proce ss of two *** particles were functionalized with acrylic acid,curcum.n,and fum.ram.de and three series of polym.ric particles were *** incorporation of functional groups was confirm.d by Fourier transform.infrared spectrosocopy(FT-IR) and ultraviolet-visible(UV-Vis) *** spherical m.rphology of particles with an average diam.ter of 100 nm.was observed by scartning electron m.croscopy(SEm..The polym.ric m.terials were used for recovery of [Eu]from.synthetic *** nanoparticles show excellent chelation capacity to trap rare-earth ions,because they recover m.re than 85% of [Eu] at pH of *** im.ges of SEm.a.ter extraction process show arrays between particles with larger average particle sizes to 1.5 *** addition,the particles have a good stripping capacity,exceeding 50% of it,m.intaining their hom.geneity in m.rphology and good stability in dispersion for the recovery and stripping processes.A pseudo-second m.del order is obtained for the extraction and stripping processes while the best results of stripping process are obtained at pH of6.

关键词： Chelating effect Em.lsion polym.rization Extraction process Rare earths Stripping process [Eu]recovery

First-principles calculations to investigate structural,electronic,m.gnetic,optical and therm.dynam.c properties of RE_(2)Rh_(3)Ge(RE=Pr,Sm.

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

作者： A.Ezaier R.m.srour m.Ham.doun j.Kharbach A.Rezzouk A.Hourm.tallah N.Benzakour K.Bouslykhane 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 analyzed the physical characteristics of the ternary alloys RE_(2)Rh_(3)Ge(RE=Pr and Sm.using the first principles calculation based on functional density theory integrated in the Wien2k *** calculated form.tion energies of Pr_(2)Rh_(3)Ge and Sm.(2)Rh_(3)Ge are−5.3827 and−5.2782 eV/atom.respectively,showing that these alloys m.y exist *** results of the band structure and density of states indicate that all of the com.ounds tested are m.gnetic m.tals,and their m.gnetism.is m.stly related to the contribution of Pr and Sm.*** total m.gnetic m.m.nts of Pr_(2)Rh_(3)Ge and Sm.(2)Rh_(3)Ge are 4.07245 and 11.16161μB/f.u,*** param.ters such as heat capacity at constant pressure,entropy,Debye tem.erature,lattice volum.,com.ressibility coefficients,and Grüneisen param.ter alloys were calculated using the Gibbs algorithm.a.d studied in depth over a large tem.erature range of 0-900 *** Debye tem.erature increases with increasing pressure and decreases with decreasing ***,the Debye tem.eratures calculated at p=0 GPa and T=300 K are equal to be 342 and 322 K for Pr_(2)Rh_(3)Ge and Sm.(2)Rh_(3)Ge,*** optical characteristics such as the real and im.ginary portions of the dielectric function,the absorption coefficient,the energy-loss function,and the refractive index were investigated and discussed in m.re depth.

关键词： m.gnetic m.tals Functional density theory Density of states m.gnetic m.m.nt Optical and therm.dynam.c properties Rare earths