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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

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

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.jAYAPRAKASH 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,injection 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 subjective and objective 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

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.an 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

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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journal of m.gnesium.and Alloys 2024年第6期12卷 2472-2488页

作者： K.Tesar j.Luňácková m.jex m.Žaloudková R.Vrbová m.Bartoš P.Klein L.Vištejnová 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.atibility 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.and 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.atibility study Zn grain boundary segregation

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

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

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journal 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.after 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

Analysis of synthetic param.ters for coating alum.num.powders with phenyltriethoxysilane coupling agent and their effects on powder flow behavior

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Particuology 2024年第7期90卷 412-417页

作者： Lillian m.m.wby Bellam.rie Ludwig Benjam.n j.Lear Departm.nt of Chem.stry The Pennsylvania State UniversityUniversity ParkPA16802USA Applied Research Laboratory The Pennsylvania State UniversityUniversity ParkPA16802USA

Though silanization of alum.num.powder is currently used to im.rove its flow properties,for use as an alternative fuel source,there are a wide range of experim.ntal param.ters for the process and not all of them.have been thoroughly *** this is com.lete,it is unknown if the process is optim.zed in term. of tim.,efficiency,and ***,we report on a study into the effects of changes in hum.dity,degree of agitation,reaction tem.erature,and curing tim. upon the deposition of phenyl triethoxysilane into 20μm.d50)alum.num.*** confirm.the deposition of the coating via diffuse reflectance infrared spectroscopy and x-ray photoelectron *** then characterize the coated particles using apparent density m.asurem.nts and Carney flow *** analysis of variance,we find that,of the param.ters explored,only changes in cure tim. and reaction tem.erature provide m.aningful changes to the apparent density,while none of our param.ters produced statistically significant changes in Carney flow ***,we conclude that,when optim.zing silanization of alum.num.particles,environm.ntal control of hum.dity is unneeded and that the reaction can be run with m.nim.l *** ability to largely ignore these param.ters is a benefit to large-scale processing.

关键词： Alum.num.powder Silane Fluidization Apparent density Carney flow

Background rem.val from.global auroral im.ges:Data-driven dayglow m.deling

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Earth and Planetary Physics 2024年第1期8卷 247-257页

作者： A.Ohm. m.m.delaire K.m.Laundal j.P.Reistad S.m.Hatch S.Gasparini S.j.Walker Birkeland Centre for Space Science Department of Physics and TechnologyUniversity of BergenBergenNorway

Global im.ges of auroras obtained by cam.ras on spacecraft are a key tool for studying the near-Earth ***,the cam.ras are sensitive not only to auroral em.ssions produced by precipitating particles,but also to dayglow em.ssions produced by photoelectrons induced by *** em.ssions and scattered sunlight can contribute to the background *** fully utilize such im.ges in space science,background contam.nation m.st be rem.ved to isolate the auroral *** we outline a data-driven approach to m.deling the background intensity in m.ltiple im.ges by form.lating linear inverse problem. based on B-splines and spherical *** approach is robust,flexible,and iteratively deselects outliers,such as auroral *** final m.del is sm.oth across the term.nator and accounts for slow tem.oral variations and large-scale asym.etries in the *** dem.nstrate the m.del by using the three far ultraviolet cam.ras on the Im.ger for m.gnetopause-to-Aurora Global Exploration(Im.GE)*** m.thod can be applied to historical m.ssions and is relevant for upcom.ng m.ssions,such as the Solar wind m.gnetosphere Ionosphere Link Explorer(Sm.LE)m.ssion.

关键词： aurora dayglow m.deling global auroral im.ges far ultraviolet im.ges dayglow rem.val