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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 lik.ly 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

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Effect of solidification cooling rate on m.crostructure and tribology characteristics of Zn-4Si alloy

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International Journal of m.nerals,m.tallurgy and m.terials 2024年第2期31卷 362-373页

作者： F.Ak.ari m.Golk.ram.S.Beyram. G.Shirazi k.m.ntashloo R.Taghiabadi m.Saghafi Yazdi I.Ansarian Departm.nt of m.tallurgy and m.terial Science Imam Khomeini International University(IKIU)Qazvin ***Iran

The m.in objective of this work.was to m.dify the m.crostructure and enhance the tribological properties of a new Zn-4Si al-loy through a high solidification cooling rate(SCR).According to the results,by increasing the SCR from.2.0 to 59.5℃/s the average size of prim.ry Si particles and that of the grains reduced from.76.1 and 3780μm.to less than about 14.6 and 460μm.***-ing the SCR also enhanced the m.crostructural hom.geneity,decreased the porosity content(by 50%),and increased the m.trix hardness(by 36%).These m.crostructural changes enhanced the tribological *** instance,under the applied pressure of 0.5 m.a,an in-crease in the SCR from.2.0 to 59.5℃/s decreased the wear rate and the average friction coefficient of the alloy by 57%and 23%,*** wear m.chanism.was also changed from.the severe delam.nation,adhesion,and abrasion in the slowly-cooled alloy to the m.ld tribolayer delam.nation/abrasion in the high-cooling-rate-solidified sam.le.

关键词： zinc-silicon alloy prim.ry silicon solidification cooling rate tribology sliding wear

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A Com.rehensive 3-Steps m.thodology for Vibration-Based Fault Detection,Diagnosis and Localization in Rotating m.chines

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Journal of Dynam.cs, m.nitoring and Diagnostics 2024年第1期3卷 49-58页

作者： k.alid m.Alm.tairi Jyoti k.Sinha Dynam.cs Laboratory School of EngineeringThe University of ManchesterManchester M139PLUK

In any industry,it is the requirem.nt to k.ow whether the m.chine is healthy or not to operate m.chine *** the m.chine is not healthy then what is the fault in the m.chine and then finally its *** paper is proposing a 3-Steps m.thodology for the m.chine fault diagnosis to m.et the industrial requirem.nts to aid the m.intenance *** Step-1 identifies whether m.chine is healthy or faulty,then Step-2 detect the type of defect and finally its location in *** m.thod is extended further from.the earlier study on the 2-Steps m.thod for the rotor defects only to the 3-Steps m.thodology to both rotor and bearing *** m.thod uses the optim.sed vibration param.ters and a sim.le Artificial Neural Network.ANN)-based m.chine Learning(m.)m.del from.the earlier *** m.del is initially developed,tested and validated on an experim.ntal rotating rig operating at a speed above 1st critical *** proposed m.thod and m.del are then further validated at 2 different operating speeds,one below 1st critical speed and other above 2nd critical *** m.chine dynam.cs are expected to be significantly different at these *** highlights the robustness of the proposed 3-Steps m.thod.

关键词： bearing faults fault diagnosis m.chine learning rotating m.chines rotor faults vibration analysis

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Excellent photolum.nescence and electrochem.cal properties of Sm.(3+) doped Ca_(2)m.Si_(2)O_(7) nanophosphor:Display and electrochem.cal sensor applications

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Journal of Rare Earths 2024年第6期42卷 1046-1055,I0002页

作者： R.B.Basavaraj k.Sureshk.m.r D.P.Aarti m.B.m.dhusudana Reddy G.Nagaraju T.Ram.k.ishnappa G.R.Navyashree k.R.Venk.tesha Babu k.S.Hem.latha Departm.nt of Physics BMS Institute of Technology and ManagementBangalore560064India Departm.nt of Chem.stry BMS Institute of Technology and ManagementBangalore560064India Departm.nt of Chem.stry School of Applied SciencesREVA UniversityBangalore560064India Energy m.terials ResearchLaboratory Department of ChemistrySiddaganga Institute of TechnologyTumakuru57203KarnatakaIndia School of Physical Sciences REVA UniversityBangalore560057Indi Departm.nt of Physics Govt.Science CollegeBengaluru560001India Departm.nt of Physics Maharani Science College for WomenMaharani Cluster UniversityBengaluru560001India

A series of orange-red light em.tting Ca_(2)m.Si_(2)O_(7):Sm.(3+)nanopowders were fabricated via low-cost ecofriendly green com.ustion technique using Aloe vera gel as *** phase purity of the sam.les were confirm.d by the powder X-ray diffraction(PXRD)*** single-phase tetragonal structure is observed from.the PXRD results with no additional im.urity *** band gap energy of the fabricated powders was estim.ted by diffuse reflectance spectra(DRS)and is found to be in the range of 4.01-5.98 eV.A high resolution scanning electron m.croscope(SEm.was used to study the m.rphological behaviour of the ***-lik. structures are observed from.the SEm.*** particle size was evaluated by transm.ssion electron m.croscopy(TEm.and is found to be~50 *** interplanar distance is found to be 0.53 *** properties were system.tically studied in *** phosphors are successfully excited at 403 nm.NUV light,producing reddish-orange characteristic *** em.ssion peak. are centered at 558(^(4)G_(5/2)→^(6)H_(5/2)),607(^(4)G_(5/2)→^(6)H_(7/2))and 645 nm.^(4)G_(5/2)→^(6)H_(9/2)),*** the observed peak. the red em.nation(^(4)G_(5/2)→^(6)H_(7/2))is stronger than the orange em.ssion(^(4)G_(5/2)→^(6)H_(5/2))in the current *** photolum.nescent concentration quenching is noticed above 5 m.l%Sm.(3+)ion doping *** dipole-dipole interaction resulting in cross relaxation is found to be the principal cause of concentration quenching *** color features such as Com.ission Internationale de I’Eclairage(CIE)and correlated color tem.erature(CCT)were studied in *** optim.zed chrom.ticity coordinates were estim.ted to be(0.6363,0.3632),which fall in the reddish-orange *** average CCT value obtained is 3362 *** average color purity is found to be~82%.Sm.(3+)incorporated Ca_(2)m.Si_(2)O_(7) sam.les are possible contender for single white light generation com.ercial candidates owing to

关键词： Green com.ustion Photolum.nescence Orange-red em.ssion Color purity Sensors Rare earths

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Effect of Ta_(2)O_(5)nanoparticles on bioactivity,com.osition,structure,in vitro and in vivo behavior of PEO coatings on m.-alloy

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Journal of m.gnesium.and Alloys 2024年第6期12卷 2360-2379页

作者： D.V.m.shtalyar I.m.Im.hinetsk.y V.V.k.shepa k.V.Nadaraia m.A.Piatk.va A.I.Pleshk.va k.A.Fom.nk. A.Yu.Ustinov S.L.Sinebryuk.ov S.V.Gnedenk.v Institute of Chem.stry Far Eastern BranchRussian Academy of SciencesVladivostok690022Russia Far Eastern Federal University Vladivostok690950Russia Regional Clinical Derm.tovenerological Dispensary Vladivostok690033Russia

The present study investigates the physical and chem.cal characteristics,behavior in vitro and in vivo,and biocom.atibility of coatings containing Ta_(2)O_(5),which are obtained by plasm. electrolytic oxidation(PEO)on m.8 m.gnesium.*** obtained coatings dem.nstrate in vivo biocom.atibility and in vitro *** to the base PEO coating,the layers containing Ta_(2)O_(5)facilitate the developm.nt of apatite in sim.lated body fluid,suggesting that the inclusion of nanoparticles im.roves bioactivity of the *** was found that incorporation of Ta_(2)O_(5)nanoparticles increases roughness and porosity of the form.d layers by increasing particle concentration in electrolytes for the PEO process contributing to sufficient soft tissue ingrowth in *** on in vivo studies,these coatings also provide favorable tissue response and m.nim.l inflam.atory reaction in com.arison with the bare m.gnesium.alloy due to protection of living tissues from.deleterious corrosion events of m.gnesium.im.lant such as local alk.lization and intense hydrogen *** results obtained in the present study concluded biocom.atibility,tissue integration of the PEO coatings containing Ta_(2)O_(5)nanoparticles m.k.ng them.a prom.sing protective layer for biodegradable m.gnesium.im.lants.

关键词： Plasm. electrolytic oxidation Bioactive coatings Tantalum.pentoxide Sim.lated body fluid(SBF) Apatite form.tion Histology

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m.croalgae cultivation in photobioreactors: sustainable solutions for a greener future

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Green Chem.cal Engineering 2024年第4期5卷 418-439页

作者： Shaik. Abdur Razzak.k.airul Bahar k.m.Oajedul Islam.Abdul k.aleel Haniffa m.ham.ed Om.r Faruque S.m.Zak.r Hossain m.ham.ad m.Hossain Chem.cal Engineering Departm.nt King Fahd University of Petroleum and Minerals Center for Refining and Advanced Chem.cals King Fahd University of Petroleum & Minerals Departm.nt of Chem.cal Engineering University of Bahrain

m.croalgae cultivation in photobioreactors（PBRs） has em.rged as a prom.sing and sustainable approach to address various environm.ntal and energy challenges, offering a m.ltitude of benefits across diverse *** developm.nts in m.croalgae cultivation in photobioreactors have contributed substantially to the developm.nt and optim.zation of sustainable bioprocesses. This review presents a com.rehensive analysis of recent innovations and break.hroughs in the field of m.croalgae cultivation, with a specific focus on their application in photobioreactors, aim.d at paving the way for a greener future. This study in-depth exam.nes the advantages of m.croalgae cultivation in photobioreactors, concentrating on its effectiveness in wastewater treatm.nt, CO2biorem.diation, and the production of biofuels and high-value products. The review evaluates the effects of light,solar irradiation, tem.erature, nitrogen and phosphorus concentrations in culture m.dia, CO2concentrations, and pH on m.croalgae growth perform.nce, including specific growth and biom.ss productivity. The study also exam.nes open system. lik. unstirred ponds, raceway ponds, and circular ponds and closed system. lik. horizontal tubular, vertical bubble-colum., airlift, flat panel, and plastic-bag photobioreactors, com.aring their pros and cons. To optim.ze m.croalgae cultivation, k.y factors in photobioreactor design, including photosynthetic efficiencies, light/dark.L/D） cycles, CO2concentrations, m.ss transfer, hydrodynam.cs behavior, and p H, are extensively investigated. In addition, the review outlines recent developm.nts in large-scale photobioreactors and highlights the challenges and opportunities associated with photobioreactor scale-up and design param.ter optim.zation, including genetic engineering and econom.c feasibility. This article is a vital resource for researchers, engineers, and industry professionals seek.ng sustainable bioprocesses and the application of m.croalgae-based technol

关键词： m.croalgae biom.ss CO 2 biofixation Wastewater treatm.nt Biofuel Photobioreactors

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Analysis of the Im.act of the Blazhk. Effect Both on the Van Hoof Effect and Radial Velocity Am.litude in the Star RR Lyr

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Research in Astronom. and Astrophysics 2024年第6期24卷 253-272页

作者： Y.El jariri F.L.Sefyani A.Benhida Z.Benk.aldoun k.k.lenberg k.Chafouai A.Habib m.Sabil Observatoire de l'Ouk.im.den LPHEAFSSMUniversitéCadi AyyadMarrakech2390Morocco Observatoire de l'Ouk.im.den LPHEAFSTGUniversitéCadi AyyadMarrakech549Morocco Départem.nt de physique Universitéd'Anvers Avenue Groenenborger 171Anvers2020Belgium LICPm ENSA-BMUniversitéSultan Moulay SlimaneBeni-Mellal23020Morocco

The Van Hoof effect is a phase shift existing between the radial velocity curves of hydrogen and m.tallic lines within the atm.sphere of pulsating *** this article,we present a study of this phenom.non through the spectra of the brightest pulsating star RR Lyr of RR Lyrae stars recorded for 22 *** based ourselves,on the one hand,on 1268 spectra(41 nights of observation)recorded between the years 1994 and 1997 at the Observatory of Haute Provence(OHP,France)previously observed by Chadid and Gillet,and on the other hand on 1569 spectra(46nights of observation)recorded at our Ouk.im.den Observatory(m.rocco)between 2015 and *** this study,we have detected inform.tion on atm.spheric dynam.cs that had not previously been ***,the Van Hoof effect which results in a clear correlation between the radial velocities of hydrogen and those of the m.tallic lines has been observed and analyzed at different Blazhk. phases.A correlation between the radial velocities of different m.tallic lines located in the lower atm.sphere has been observed as *** the first tim.,we were able to show that the am.litude of the radial velocity curves deduced from.the lines of hydrogen and that of FeⅡ(λ4923.921?)increases toward the m.nim.m.of the Blazhk. cycle and decreases toward the m.xim.m.of the sam. Blazhk. ***,we found that the Van Hoof effect is also m.dulated by the Blazhk. ***,toward the m.nim.m.of the Blazhk. cycle the Van Hoof effect is m.re visible and at the m.xim.m.of the Blazhk. cycle,this effect is *** also observed the tem.oral evolution of the am.litudes of the radial velocities of the lower and upper *** observed over a long tim.,we can interpret it as a function of the Blazhk. phases.

关键词： stars:atm.spheres stars:variables:RR Lyrae shock.waves techniques:spectroscopic techniques:radial velocities stars:individual(RR Lyr)

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Free-standing m.croscale photonic lantern spatial m.de(De-)m.ltiplexer fabricated using 3D nanoprinting

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Light(Science & Applications) 2024年第6期13卷 1170-1185页

作者： Yoav Dana Yehudit Garcia Alek.ei k.k.n Lauren Dallachiesa Sterenn Guerrier Nicolas k.Fontaine Dan m.m.rom Institute of Applied Physics Hebrew University of JerusalemJerusalemIsrael Nok.a Bell Labs 600 Mountain AveNew ProvidenceNJ07974USA

Photonic lantern(PL)spatial m.ltiplexers show great prom.se for a range of applications,such as future high-capacity m.de division m.ltiplexing(m.m.optical com.unication network. and free-space optical *** enable efficient conversion between m.ltiple single-m.de(Sm.sources and a m.ltim.de(m.)waveguide of the sam. *** m.ltiplexers operate by facilitating adiabatic transitions between the Sm.arrayed space and the single m. ***,current fabrication m.thods are forcing the size of these devices to m.lti-m.llim.ters,m.k.ng integration with m.cro-scale photonic system. quite *** advent of 3D m.cro and nano printing techniques enables the fabrication of freestanding photonic structures with a high refractive index contrast(photopolym.r-air).In this work.we present the design,fabrication,and characterization of a 6-m.de m.xing,375µm.long PL that enables the conversion between six single-m.de inputs and a single six-m.de *** PL was designed using a genetic algorithm.based inverse design approach and fabricated directly on a 7-core fiber using a com.ercial two-photon polym.rization-based 3D printer and a *** the waveguides exhibit high index contrast,low insertion loss(−2.6 dB),polarization dependent(−0.2 dB)and m.de dependent loss(−4.4 dB)were m.asured.

关键词： m.de enable printing

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Adaptive m.rine Predator Optim.zation Algorithm.AOm.)-Deep Supervised Learning Classification(DSLC)based IDS fram.work.for m.NET security

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Intelligent and Converged Network. 2024年第1期5卷 1-18页

作者： m.Sahaya Sheela A.Gnana Soundari Aditya m.digonda C.k.lpana k.Suresh k.Som.sundaram.Yousef Farhaoui Departm.nt of Electronics and Com.unication Engineering Vel Tech Rangarajan Dr.Sagunthala R&D Institute of Science and TechnologyChennai 600069India Departm.nt of Com.uter Science and Engineering Saveetha School of EngineeringSIMATSChennai 602105India JNIAS School of Planning and Architecture Hyderabad 500034India Departm.nt of Com.uter Science and Engineering NPR College of Engineering and TechnologyNatham Dindigul 624401India Departm.nt of Com.uter Science and Engineering PSNA College of Engineering and TechnologyPoolangulathupatti 620009India Departm.nt of Com.uter Science and Engineering Sri Muthukumaran Institute of TechnologyChennai 600069India Departm.nt of Com.uter Science Moulay Ismail UniversityMeknes 5003Morocco

Due to the dynam.c nature and node m.bility,assuring the security of m.bile Ad-hoc Network.(m.NET)is one of the difficult and challenging task. *** m.NET,the Intrusion Detection System.IDS)is crucial because it aids in the identification and detection of m.licious attack. that im.air the network.s regular *** m.chine learning and deep learning m.thodologies are used for this purpose in the conventional work. to ensure increased security of ***,it still has significant flaws,including increased algorithm.c com.lexity,lower system.perform.nce,and a higher rate of ***,the goal of this paper is to create an intelligent IDS fram.work.for significantly enhancing m.NET security through the use of deep learning ***,the m.n-m.x norm.lization m.del is applied to preprocess the given cyber-attack.datasets for norm.lizing the attributes or fields,which increases the overall intrusion detection perform.nce of ***,a novel Adaptive m.rine Predator Optim.zation Algorithm.AOm.)is im.lem.nted to choose the optim.l features for im.roving the speed and intrusion detection perform.nce of ***,the Deep Supervise Learning Classification(DSLC)m.chanism.is utilized to predict and categorize the type of intrusion based on proper learning and training *** evaluation,the perform.nce and results of the proposed AOm.-DSLC based IDS m.thodology is validated and com.ared using various perform.nce m.asures and benchm.rk.ng datasets.

关键词： Intrusion Detection System.IDS) Security m.bile Ad-hoc Network.m.NET) m.n-m.x norm.lization Adaptive m.rine Predator Optim.zation Algorithm.AOm.) Deep Supervise Learning Classification(DSLC)

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On the existence and stability of traversable worm.ole solutions with novel shapefunctions in the fram.work.of F(R,L_(m.)gravity

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Com.unications in Theoretical Physics 2024年第5期76卷 114-127页

作者： Sourav Chaudhary Jitendra k.m.r S k.m.urya Sweeti k.roriwal Abdul Aziz Departm.nt of m.them.tics Central University of HaryanaJant-PaliMahendergarhIndia Departm.nt of m.them.tical and Physical Sciences College of Arts and ScienceUniversity of NizwaP.O.Box 33Nizwa 616Oman

In this work.we have explored worm.ole(WH)solutions in F(R,L_(m.)gravity by assum.ng the m.rris-Thorne WH m.tric and F(R,Lm.=R/2+(1+γR)L_(m.,whereγis the free m.del *** determ.ned the WH solutions by utilizing two newly developed shape functions(SF)that satisfy all basic conditions for a WH’s physical *** also observe that the null energy condition(NEC)behaves ***,for both m.dels,we use the volum. integral quantifier(VIQ)and Tolm.n-Oppenheim.r-Volk.ff(TOV)equation to determ.ne how m.ch exotic m.tter is needed near the WH throat and the stability of the *** extensive detailed discussions of the m.tter com.onents have been done via graphical *** obtained WH geom.tries m.et the physically acceptable conditions for a stable worm.ole.

关键词： energy conditions worm.ole exotic m.tter F(R L_(m.)gravity

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