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Background removal from global auroral images:Data-driven dayglow modeling

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Earth and planetary physics 2024年第1期8卷 247-257页

作者： A.Ohma m.madelaire 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 images of auroras obtained by cameras on spacecraft are a key tool for studying the near-Earth ***,the cameras are sensitive not only to auroral emissions produced by precipitating particles,but also to dayglow emissions produced by photoelectrons induced by *** emissions and scattered sunlight can contribute to the background *** fully utilize such images in space science,background contamination must be removed to isolate the auroral *** we outline a data-driven approach to modeling the background intensity in multiple images by formulating linear inverse problems based on B-splines and spherical *** approach is robust,flexible,and iteratively deselects outliers,such as auroral *** final model is smooth across the terminator and accounts for slow temporal variations and large-scale asymmetries in the *** demonstrate the model by using the three far ultraviolet cameras on the Imager for magnetopause-to-Aurora Global Exploration(ImAGE)*** method can be applied to historical missions and is relevant for upcoming missions,such as the Solar wind magnetosphere Ionosphere Link Explorer(SmILE)mission.

关键词： aurora dayglow modeling global auroral images far ultraviolet images dayglow removal

In-situ study of the microstructure evolution during tension of a mg-Y-Zn-Al alloy processed by rapidly solidified ribbon consolidation technique

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Journal of magnesium and Alloys 2024年第5期12卷 2024-2040页

作者： Jeno Gubicza Kristián máthis péter Nagy péter Jenei Zoltán Hegedus Andrea Farkas Jozef Vesely Shin-ichi Inoue Daria Drozdenko Yoshihito Kawamura Department of materials physics Faculty of ScienceEotvos Loránd UniversityPázmány P.sétány 1/ABudapest H-1117Hungary Department of physics of materials Faculty of Mathematics and PhysicsCharles UniversityKe Karlovu 512116 Praha 2Czech Republic Deutsches Elektronen-Synchrotron DESY Notkestr.85Hamburg 22603Germany magnesium Research Center Kumamoto University2-39-1 KurokamiChuo-kuKumamoto 860-8555Japan

mg-Y-Zn-Al alloys processed by rapidly solidified ribbon consolidation(RSRC)technique exhibit an exceptional mechanical performance indicating promising application *** material has a bimodal microstructure consisting of fine recrystallized and coarse non-recrystallized grains with solute-rich stacking faults forming cluster arranged layers(CALs)and nanoplates(CANaps),or complete long period stacking ordered(LpSO)*** order to reveal the deformation mechanisms,in-situ synchrotron X-ray diffraction line profile analysis was employed for a detailed study of the dislocation arrangement created during tension in mg-0.9%Zn-2.05%Y-0.15%Al(at%)*** uncovering the effect of the initial microstructure on the mechanical performance,additional samples were obtained by annealing of the as-consolidated specimen at 300 and 400℃ for 2 *** heat treatment at 300℃ had no significant effect on the initial microstructure,its evolution during tension and,thus,the overall deformation behavior under tensile *** the other hand,annealing at 400℃ resulted in a significant increase of the recrystallized grains fraction and a decrease of the dislocation density,leading to only minor degradation of the mechanical *** maximum dislocation density at the failure of the samples corresponding to the plastic strain of 10-25% was estimated to be about 16-20×10^(14)m^(-2).The diffraction profile analysis indicated that most dislocations formed during tension were of non-basal and pyramidal types,what was also in agreement with the Schmid factor values revealed independently from orientation *** was also shown that the dislocation-induced Taylor hardening was much lower below the plastic strain of 3% than above this value,which was explained by a model of the interaction between prismatic dislocations and CANaps/LpSO plates.

关键词： mg-Zn-Y-Al alloy Long period stacking ordered(LpSO)phase Cluster arranged nanoplates(CANaps) Annealing Tension Dislocation density Hardening

Single atom Cu-N-C catalysts for the electro-reduction of CO_(2) to CO assessed by rotating ring-disc electrode

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Journal of Energy Chemistry 2024年第1期88卷 169-182,I0004页

作者： S.pérez-Rodríguez m.Gutiérrez-Roa C.Giménez-Rubio D.Ríos-Ruiz p.Arévalo-Cid m.V.martínez-Huerta A.Zitolo m.J.Lázaro D.Sebastián Instituto de Carboquímica(CSIC) Miguel Luesma Castán 450018 ZaragozaSpain Instituto de Catálisis y petroleoquímica(CSIC) Marie Curie 228049 MadridSpain Synchrotron SOLEIL L’Orme des MerisiersDépartementale 12891190France

The electrochemical CO_(2) reduction reaction(CO_(2)RR) to controllable chemicals is considered as a promising pathway to store intermittent renewable energy. Herein, a set of catalysts based on copper-nitrogendoped carbon xerogel(Cu-N-C) are successfully developed varying the copper amount and the nature of the copper precursor, for the efficient CO_(2)RR. The electrocatalytic performance of Cu-N-C materials is assessed by a rotating ring-disc electrode(RRDE), technique still rarely explored for CO_(2)RR. For comparison, products are also characterized by online gas chromatography in a H-cell. The as-synthesized Cu-NC catalysts are found to be active and highly CO selective at low overpotentials(from -0.6 to -0.8 V ***) in 0.1 m KHCO_(3), while H_(2) from the competitive water reduction appears at larger overpotentials(-0.9 V vs. RHE). The optimum copper acetate-derived catalyst containing Cu-N_(4) moieties exhibits a CO_(2)-to-CO turnover frequency of 997 h^(-1) at -0.9 V vs. RHE with a H_(2)/CO ratio of 1.8. These results demonstrate that RRDE configuration can be used as a feasible approach for identifying electrolysis products from CO_(2)RR.

关键词： Cu-N-C Carbon xerogel Rotating ring disc electrode Carbon dioxide reduction reaction Carbon monoxide

Collisionless shock acceleration of protons in a plasma slab produced in a gas jet by the collision of two laser-driven hydrodynamic shockwaves

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matter and Radiation at Extremes 2024年第2期9卷 12-25页

作者： J.-R.marquès L.Lancia p.Loiseau p.Forestier-Colleoni m.Tarisien E.Atukpor V.Bagnoud C.Brabetz F.Consoli J.Domange F.Hannachi p.Nicolaï m.Salvadori B.Zielbauer LULI CNRSÉcole PolytechniqueCEASorbonne UniversitéInstitut Polytechnique de Paris91128 Palaiseau CedexFrance CEA DAMDIF91297 Arpajon CedexFrance Universitéparis-Saclay CEALMCE91680 Bruyères-le-ChatelFrance CENBG CNRS-IN2P3Universitéde Bordeaux33175 Gradignan CedexFrance GSI Helmholtzzentrum für Schwerionenforschung GmbH Planckstraße 164291 DarmstadtGermany University of Darmstadt Schloßgartenstr.764289 DarmstadtGermany ENEA Fusion and Technologies for Nuclear Safety Department C.R.FrascatiVia Enrico Fermi 45FrascatiRomeItaly CELIA Universitéde Bordeaux–CNRS–CEA33405 TalenceFrance Universitéparis-Saclay CEALIDYL91191 Gif-sur-YvetteFrance

We have recently proposed a new technique of plasma tailoring by laser-driven hydrodynamic shockwaves generated on both sides of a gas jet[marquès et al.,*** 28,023103(2021)].In a continuation of this numerical work,we study experimentally the influence of the tailoring on proton acceleration driven by a high-intensity picosecond laser in three cases:without tailoring,by tailoring only the entrance side of the picosecond laser,and by tailoring both sides of the gas *** tailoring,the acceleration is transverse to the laser axis,with a low-energy exponential spectrum,produced by Coulomb *** the front side of the gas jet is tailored,a forward acceleration appears,which is significantly enhanced when both the front and back sides of the plasma are *** forward acceleration produces higher-energy protons,with a peaked spectrum,and is in good agreement with the mechanism of collisionless shock acceleration(CSA).The spatiotemporal evolution of the plasma profile is characterized by optical shadowgraphy of a probe *** refraction and absorption of this beam are simulated by post-processing 3D hydrodynamic simulations of the plasma *** with the experimental results allows estimation of the thickness and near-critical density of the plasma slab produced by tailoring both sides of the gas *** parameters are in good agreement with those required for CSA.

关键词： acceleration hydrodynamic collision

Europium recovery process by means of polymeric nanoparticles functionalized with acrylic acid,curcumin and fumaramide

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Journal of Rare Earths 2024年第10期42卷 1950-1959页

作者： p.A.martínez-montoya J.m.del Río A.de J.morales-Ramirez m.Corea Escuela Superior de Ingeniería Química e Industrias Extractivas ESIQIE-IPNDepartamento de Ingeniería Metalúrgica UPALM S/N Col.Lindavista Escuela Superior de Ingenieria Química 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

polymeric nanoparticles of poly(methyl methacrylate) were obtained by emulsion polymerization techniques in a proce ss of two *** particles were functionalized with acrylic acid,curcumin,and fumaramide and three series of polymeric particles were *** incorporation of functional groups was confirmed by Fourier transform-infrared spectrosocopy(FT-IR) and ultraviolet-visible(UV-Vis) *** spherical morphology of particles with an average diameter of 100 nm was observed by scartning electron microscopy(SEm).The polymeric materials were used for recovery of [Eu]from synthetic *** nanoparticles show excellent chelation capacity to trap rare-earth ions,because they recover more than 85% of [Eu] at pH of *** images 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,maintaining their homogeneity in morphology and good stability in dispersion for the recovery and stripping processes.A pseudo-second model order is obtained for the extraction and stripping processes while the best results of stripping process are obtained at pH of6.

关键词： [Eu] recovery Chelating effect Extraction process Stripping process Emulsion polymerization Rare earths

The initial stages of Li_(2)O_(2) formation during oxygen reduction reaction in Li-O_(2) batteries:The significance of Li_(2)O_(2) in charge-transfer reactions within devices

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Journal of Energy Chemistry 2024年第1期88卷 223-231,I0006页

作者： Daniela m.Josepetti Bianca p.Sousa Simone A.J.Rodrigues Renato G.Freitas Gustavo Doubek Advanced Energy Storage Division LABCenter for Innovation on New EnergiesSchool of Chemical EngineeringUniversity of CampinasAv Albert Einstein 50013083-852CampinasSPBrazil Institute of physics&Department of Chemistry Laboratory of Computational MaterialsFederal University of Mato Grosso78060-900CuiabáMTBrazil

Lithium-oxygen batteries are a promising technology because they can greatly surpass the energy density of lithium-ion ***,this theoretical characteristic has not yet been converted into a real device with high *** with air contamination,metallic lithium reactivity,and complex discharge and charge reactions are the main issues for this technology.A fast and reversible oxygen reduction reaction(ORR)is crucial for good performance of secondary batteries',but the partial knowledge of its mechanisms,especially when devices are concerned,hinders further *** this perspective,the present work uses operando Raman experiments and electrochemical impedance spectroscopy(EIS)to assess the first stages of the discharge processes in porous carbon electrodes,following their changes cycle by cycle at initial operation.A growth kinetic formation of the discharge product signal(Li_(2)O_(2))was observed with operando Raman,indicating a first-order reaction and enabling an analysis by a microkinetic *** solution mechanism in the evaluated system was ascribed for an equivalent circuit with three time *** the time constant for the anode interface reveals to remain relatively constant after the first discharge,its surface seemed to be more *** model indicated that the reaction occurs at the Li_(2)O_(2) surface,decreasing the associated resistance during the initial discharge ***,the growth of Li_(2)O_(2) forms a hetero-phase between Li_(2)O_(2)/electrolyte,while creating a more compact and homogeneous on the Li_(2)O_(2)/cathode *** methodology here described thus offers a way of directly probing changes in surface chemistry evolution during cycling from a device through EIS analysis.

关键词： Li-O_(2)battery Operando Raman analysis Equivalent circuit modeling Time-constant distribution

Evaluation of mechanical properties and Surface Quality of Wood from Bosnia and Herzegovina Exposed to Outdoor Conditions

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Journal of Renewable materials 2024年第8期12卷 1417-1431页

作者： Hasanagić R. Šljivo U. Fathi L. Gautam p. Bahmani m. Humar m. Department of Wood Science and Technology Faculty of Technical Engineering University of Bihać Bihać 77000 Bosnia and Herzegovina Department of Wood and Furniture Industry Engineering Faculty of Resources and Earth Science Shahrekord University Shahrekord 64165478 Iran Department of Botany Institute of Science Banaras Hindu University Uttar Pradesh Varanasi 221005 India Biotechnical Faculty Department of Wood Science University of Ljubljana Ljubljana 1501 Slovenia

This study investigated the mechanical properties of beech (Fagus sylvatica L.) and fir (Abies alba) wood from Bosnia and Herzegovina under outdoor exposure. Samples were exposed for 3-month exposure to assess bending strength, color changes, and surface quality. Results showed outdoor exposure negatively affected mechanical properties, particularly in samples with extended finger joints, causing significant surface cracks in uncoated sam-ples. Beech wood exhibited notable color changes under exposure, with approximately 50% darkening without coating compared to 25% under covered conditions. Coated samples displayed minimal color changes, affirming the efficacy of surface treatment. Fir wood exhibited a roughness of 8.264 μm, while beechwood average roughness increased from 6.767 to 13.916 μm after exposure, with micro-pore development affecting water perfor-mance. microscopic analysis identified prevalent fungal colonies, including penicillium, Aureobasidium, Sclerophoma, and Chaetomium, underscoring their role in organic matter decomposition. This study highlights the importance of wood exposure and treatment selection for various applications. © 2024 The Authors.

关键词： cracks mechanical properties outdoor conditions wood species

Solid-liquid extraction for yttrium recovery using porous polymeric resin(XAD-7) functionalized with D_(2)EHpA

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Journal of Rare Earths 2024年第9期42卷 1764-1773,I0005页

作者： p.A.martínez-montoya R.G.Sanchez-Alvarado D.Y.medina-Velazquez m.L.Carrera-Jota p.Garnica-Chávez A.de J.morales-Ramirez Higher School of Chemical Engineering and Extractive Industries ESIQIEIPNDepartment of Metallurgical EngineeringUPALM S/NCol.LindavistaGustavo A.Madero Cd.de MéxicoC.P07738Mexico metropolitan Autonomous University Department of MaterialsBasic Sciences and EngineeringAv.San Pablo No.180Col.Reynosa TamaulipasCd.de MéxicoC.P02200Mexico Center for Research and Technological Innovation CIITECIPNCda.de CECATIs/nSanta CatarinaAzcapotzalcoC.P02250CDMXMexico

The recovery of yttrium is proposed by applying a solid-liquid extraction process using di-2-ethyl hexylphosphoric acid(D2EHpA) as extracting *** extracting agents were supported on a macro porous polymeric resin XAD-7(solid phase).Yttrium ions extraction and discharge tests were performed,firstly from a synthetic aqueous solution of 100 mg/L Y(liquid phase) at 25℃ with *** effects of pH of aqueous solutions bearing yttrium,volume fraction of extracting agents and the solid/liquid(S/L)ratio on the yttrium recovery were *** most favorable conditions for yttrium ions extraction are;20 vol% D_(2)EHpA functionalized resin,pH=1.5 and an S/L ratio of 10 mg/mL The discharge of yttrium ions was done under the same conditions of extraction stage,using a 2 mol/L [H_(2)SO_(4)] as stripping *** to 80% yttrium is extracted,while 75% yttrium is recovered in the striping *** all experiments,the reaction equilibrium is reached after 20 min,and the kinetics for the extraction stage was determined as a second-order ***,experiments were carried out to discharge the yttriumloaded resins,and it has been determined that the best pH value to strip the Y ions is *** tests of extraction and discharge for yttrium ions show that the functionalized resin can work at least five cycles without decreasing its ***,the proposed process was tested in a real solution with Y ions fro m a waste fluorescent la mp powder leached in H_(2)SO_(4),demonstrating the ability to effectively recover yttrium,separating it from various metals from the studied residue.

关键词： Yttrium recovery Rare earth solid-liquid extraction XAD-7 resin Fluorescent lamps recycling Solid-liquid kinetics extraction

Comparison of the Anatomy and Adaptability of Reconstructed Teeth with Natural Teeth:An Innovative Approach in Forensic Dentistry

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Journal of Forensic Science and medicine 2024年第1期10卷 47-54页

作者： Supraja S p m Tejaswi Ravikanth manyam mohan Kumar pasupuleti Swetha p Ramesh Kumar Budumuru Department of Oral and maxillofacial pathology Vishnu Dental CollegeBhimavaramAndhra PradeshIndia Vishnu Dental College BhimavaramAndhra PradeshIndia Department of periodontics and Implantology Vishnu Dental CollegeBhimavaramAndhra PradeshIndia Department of Oral medicine and Radiology Vishnu Dental CollegeBhimavaramAndhra PradeshIndia

Background:Forensic tooth reconstruction is the technique of reconstructing the morphology of a missing tooth from the intra-alveolar morphology of dental sockets from skeletal *** and Objectives:The aim and objective of the study are to compare and investigate whether the anatomy and adaptability of reconstructed teeth simulate with the natural tooth and to investigate whether the dental materials have potential in reconstruction of *** and methods:An in vitro experimental study was undertaken on a human *** to the Fédération Dentaire Internationale,charting will be done based on the number of teeth *** entire study will be conducted in three phases using dental *** 1 comprised preparation for negative replica,where an impression will be taken,phase 2 comprised preparation of a positive replica or cast,and phase 3 comprised tooth reconstruction using the flowable ***:The specimen tooth(which had been taken from its socket)and the newly constructed tooth were compared,and when the length of the newly constructed root was measured using digital vernier calipers,there was a disparity of 0.5-1 *** cone-beam computed tomography radiographs demonstrated the necessary ***:The present study demonstrated that dental information can be obtained even when teeth are absent postmortem by making an attempt to recreate the teeth using dental materials while documenting the intra-alveolar anatomy of the dental root socket.

关键词： Adaptability anatomy reconstruction teeth