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Converting TREx-RGB green-channel data to 557.7 nm auroral intensity:Methodology and initial results

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Earth and Planetary Physics 2024年第1期8卷 258-274页

作者： Jun Liang D.M.Gillies E.Spanswick E.F.Donovan University of Calgary CalgaryT2N 1N4Canada

The recently deployed Transition Region Explorer(TREx)-RGB(red-green-blue)all-sky imager(ASI)is designed to capture“true color”images of the aurora and *** the 557.7 nm green line is usually the brightest emission line in visible auroras,the green channel of a TREx-RGB camera is usually dominated by the 557.7 nm *** this rationale,the TREx mission does not include a specific 557.7 nm imager and is designed to use the RGB green-channel data as a proxy for the 557.7 nm *** this study,we present an initial effort to establish the conversion ratio or formula linking the RGB green-channel data to the absolute intensity of 557.7 nm auroras,which is crucial for quantitative uses of the RGB *** illustrate two approaches:(1)through a comparison with the collocated measurement of green-line auroras from the TREx spectrograph,and(2)through a comparison with the modeled green-line intensity according to realistic electron precipitation flux measurements from low-Earth-orbit satellites,with the aid of an auroral transport *** demonstrate the procedures and provide initial results for the TREx-RGB ASIs at the Rabbit Lake and Lucky Lake *** RGB response is found to be *** conversion ratios or formulas between RGB green-channel data and the green-line auroral intensity are given and can be applied immediately by TREx-RGB data *** methodology established in this study will also be applicable to the upcoming SMILE ASI mission,which will adopt a similar RGB camera system in its deployment.

关键词： TREx RGB green-line aurora auroral transport model

Sex-specifc seasonal variations of wild boar distance traveled and home range size

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Current Zoology 2024年第3期70卷 284-290页

作者： Silvia Cavazza Rudy Brogi Marco Apollonio Department of Veterinary Medicine University of Sassarivia Vienna 2I-07100 SassariItaly

Distance traveled and home range size describe how animals move in *** seasonal variations of these parameters are important to comprehensively understand animal ecology and its connection with reproductive behavior and energy *** usually estimate the distance traveled as the sum of the straight-line displacements between sampled positions,but this approach is sensitive to the sampling frequency and does not account for the tortuosity of the animal’s *** means of the continuous-time movement modeling which takes into account autocorrelation and tortuosity of movement data,we estimated the distance traveled and monthly home range size of 28 wild boar Sus scrofa and modeled their inter-sexual seasonal *** traveled longer distances and used larger home ranges than females,particularly during the rut in autumn-winter,consistently with the different biological cycles of males and *** enlarged their home ranges during the rut but traveled constant average distances along the year,whereas females traveled shorter distances in correspondence with the peak of food resources and birth periods but exhibited constant home range size across *** differences between the seasonal variation patterns of distance traveled and home range size,observed in both sexes,revealed the complex relationship between these two aspects of spatial behavior and the great opportunity of including both distance traveled and home range size in behavioral ecology *** provided a detailed analysis of wild boar spatial behavior and its relationships with the reproductive cycles of males and females,promoting a deeper comprehension of their behavioral ecology.

关键词： continuous-time ctmm daily range movements spatial behavior Sus scrofa

Experimental and numerical investigation to elucidate the fluid flow through packed beds with structured particle packings

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Particuology 2024年第6期89卷 218-237页

作者： Shirin Patil Christian Gorges Joel Lòpez Bonilla Moritz Stelter Frank Beyrau Berend van Wachem Laboratory of Technical Thermodynamics Otto-von-Guericke-Universität MagdeburgUniversitätsplatz 239106 MagdeburgGermany Chair of Mechanical Process Engineering Otto-von-Guericke-Universität MagdeburgUniversitätsplatz 239106 MagdeburgGermany

The present paper presents an experimental and numerical investigation of the dispersion of the gaseous jet flow and co-flow for the simple unit cell(SUC)and body-centred cubic(BCC)configuration of particles in packed *** experimental setup is built in such a way that suitable and simplified boundary conditions are imposed for the corresponding numerical framework,so the simulations can be done under very similar conditions as the ***,a porous plate is used for the co-flow to achieve the uniform velocity and the fully developed flow is ensured for the jet *** SUC and BCC particle beds consist of 3D-printed spheres,and the non-isotropy near the walls is mostly eliminated by placing half-spheres at the channel *** flow velocities are analysed directly at the exit of the particle bed for both beds over 36 pores for the SUC configuration and 60 pores for the BCC configuration,for particle Reynolds numbers of 200,300,and *** particle image velocimetry is experimentally arranged in such a way that the velocities over the entire region at the exit of the packed bed are obtained *** numerical method consists of a state-of-the-art immersed boundary method with adaptive mesh *** paper presents the pore jet structure and velocity field exiting from each pore for the SUC and BCC packed particle *** numerical and experimental studies show a good agreement for the SUC configuration for all flow *** the BCC configuration,some differences can be observed in the pore jet flow structure between the simulations and the experiments,but the general flow velocity distribution shows a good overall *** axial velocity is generally higher for the pores located near the centre of the packed bed than for the pores near the *** addition,the axial velocities are observed to increase near the peripheral pores of the packed *** behaviour is predominant for the BCC configuration as compared to t

关键词： Uniform particle packing Packed bed reactor Stereo particle image velocimetry Immersed boundary method

Corrosion Investigation by Scanning Electrochemical Microscopy of AISI 446 and Ti-Coated AISI 446 Ferritic Stainless Steel as Potential Material for Bipolar Plate in PEMWE

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Acta Metallurgica Sinica(English Letters) 2024年第4期37卷 607-619页

作者： Andrea Kellenberger Nicolae Vaszilcsin Mircea Laurentiu Dan Ion Mitelea Alexandru Adrian Geana Sigrid Lædre Corneliu M.Craciunescu Faculty of Industrial Chemistry and Environmental Engineering Politehnica University TimisoaraPiata Victoriei 2300006TimisoaraRomania Faculty of Mechanical Engineering Politehnica University TimisoaraPiata Victoriei 2300006TimisoaraRomania SINTEF Industry 7465TrondheimNorway

The components of proton exchange membrane water electrolysers frequently experience corrosion issues, especially at high anodic polarization, that restrict the use of more affordable alternatives to titanium. Here, we investigate localized corrosion processes of bare and Ti-coated AISI 446 ferritic stainless steel under anodic polarization by scanning electrochemical microscopy (SECM) in sodium sulphate and potassium chloride solutions. SECM approach curves and area scans measured at open-circuit potential (OCP) of the samples in the feedback mode using a redox mediator evidence a negative feedback effect caused by the surface passive film. For the anodic polarization of the sample, the substrate generation-tip collection mode enables to observe local generation of iron (II) ions, as well as formation of molecular oxygen. For the uncoated AISI 446 sample, localized corrosion is detected in sodium sulphate solution simultaneously with oxygen formation at anodic potentials of 1.0 V vs. Ag/AgCl, whereas significant pitting corrosion is observed even at 0.2 V vs. Ag/AgCl in potassium chloride solution. The Ti-coated AISI 446 sample reveals enhanced corrosion resistance in both test solutions, without any evidence of iron (II) ions generation at anodic potentials of 1.2 V vs. Ag/AgCl, where only oxygen formation is observed.

关键词： Ferritic stainless steel Corrosion Ti coating Scanning electrochemical microscopy(SECM) Magnetron sputtering Proton exchange membrane water electrolysis(PEMWE)

Ultra-high-aspect-ratio structures through silicon using infrared laser pulses focused with axicon-lens doublets

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Light(Advanced Manufacturing) 2024年第3期5卷 1-15页

作者： Niladri Ganguly Pol Sopena David Grojo Aix-Marseille University CNRSLP3 UMR 7341F-13009 MarseilleFrance

We describe how a direct combination of an axicon and a lens can represent a simple and efficient beam-shaping solution for laser material processing *** produce high-angle pseudo-Bessel micro-beams at 1550 nm,which would be difficult to produce by other *** with appropriate stretching of femtosecond pulses,we access optimized conditions inside semiconductors allowing us to develop high-aspect-ratio refractive-index writing *** ultrafast microscopy techniques,we characterize the delivered local intensities and the triggered ionization dynamics inside silicon with 200-fs and 50-ps *** similar plasma densities are produced in both cases,we show that repeated picosecond irradiation induces permanent modifications spontaneously growing shot-after-shot in the direction of the laser beam from front-surface damage to the back side of irradiated silicon *** conditions for direct microexplosion and microchannel drilling similar to those today demonstrated for dielectrics still remain ***,this work evidences higher energy densities than those previously achieved in semiconductors and a novel percussion writing modality to create structures in silicon with aspect ratios exceeding~700 without any motion of the *** estimated transient change of conductivity and measured ionization fronts at near luminal speed along the observed microplasma channels support the vision of vertical electrical connections optically controllable at GHz repetition *** permanent silicon modifications obtained by percussion writing are light-guiding structures according to a measured positive refractive index change exceeding *** findings open the door to unique monolithic solutions for electrical and optical through-silicon-vias which are key elements for vertical interconnections in 3D chip stacks.

关键词： Beam-shaping Infrared ultrafast laser Silicon processing Through-silicon-via

Optimizing laser coupling,matter heating,and particle acceleration from solids using multiplexed ultraintense lasers

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Matter and Radiation at Extremes 2024年第4期9卷 16-28页

作者： Weipeng Yao Motoaki Nakatsutsumi Sébastien Buffechoux Patrizio Antici Marco Borghesi Andrea Ciardi Sophia N.Chen Emmanuel d’Humières Laurent Gremillet Robert Heathcote Vojtech Horny Paul McKenna Mark N.Quinn Lorenzo Romagnani Ryan Royle Gianluca Sarri Yasuhiko Sentoku Hans-Peter Schlenvoigt Toma Toncian Olivier Tresca Laura Vassura Oswald Willi Julien Fuchs LULI-cnrs CEASorbonne UniversitéEcole PolytechniqueInstitut Polytechnique de ParisF-91128 Palaiseau CedexFrance Sorbonne Université Observatoire de ParisUniversité PSLCNRSLERMAF-75005 ParisFrance INRS-EMT 1650 BoulLionel-BouletVarennesQuebec J3X 1S2Canada Center for Plasma Physics School of Mathematics and PhysicsQueen’s University BelfastBelfast BT71NNUnited Kingdom “Horia Hulubei”National Institute for Physics and Nuclear Engineering 30 Reactorului StreetRO-077125 Bucharest-MagureleRomania University of Bordeaux Centre Lasers Intenses et ApplicationsCNRSCEAUMR 5107F-33405 TalenceFrance CEA DAMDIFF-91297 ArpajonFrance Université Paris-Saclay CEALMCE91680 Bruyères-le-ChatelFrance Central Laser Facility STFC Rutherford Appleton LaboratoryDidcotUnited Kingdom SUPA Department of PhysicsUniversity of StrathclydeGlasgow G40NGUnited Kingdom Department of Physics University of NevadaRenoNevada 89557USA Institute of Laser Engineering Osaka University2-6 YamadaokaSuitaOsaka 565-0871Japan Institut fur Laser und Plasmaphysik Heinrich Heine Universitat DusseldorfDusseldorfGermany

Realizing the full potential of ultrahigh-intensity lasers for particle and radiation generation will require multi-beam arrangements due to technology ***,we investigate how to optimize their coupling with solid ***,we show that overlapping two intense lasers in a mirror-like configuration onto a solid with a large preplasma can greatly improve the generation of hot electrons at the target front and ion acceleration at the target *** underlying mechanisms are analyzed through multidimensional particle-in-cell simulations,revealing that the self-induced magnetic fields driven by the two laser beams at the target front are susceptible to reconnection,which is one possible mechanism to boost electron *** addition,the resistive magnetic field generated during the transport of the hot electrons in the target bulk tends to improve their *** simulations also indicate that such effects can be further enhanced by overlapping more than two laser beams.

关键词： laser acceleration particle

Flotation a Mature Technology in Deinking Processes： New Challenges and Applications

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国际造纸 2013年第1期32卷 30-42页

作者： D.Beneventi A.Lascar F.Vaulot S.Pottier 关颖 lgp2-cnrs KADANT

自20世纪50年代用于矿物加工的Denver槽首次工业应用以来,通过化学添加剂配方和浮选单元/多级浮选设计两方面的改进大大提高了浮选脱墨技术.如今,使用适合的浮选化学和先进的多级浮选可达到较高的油墨去除率/选择性,而且浮选脱墨一直被... 详细信息

自20世纪50年代用于矿物加工的Denver槽首次工业应用以来,通过化学添加剂配方和浮选单元/多级浮选设计两方面的改进大大提高了浮选脱墨技术.如今,使用适合的浮选化学和先进的多级浮选可达到较高的油墨去除率/选择性,而且浮选脱墨一直被认为是一项成熟技术.然而,在整个脱墨过程中,浮选单元要承受最高的污泥产生量,并且其对原材料和工艺水质的波动非常敏感.尽管现代浮选脱墨生产线的效率较高,但造纸工业目前仍通过优化浮选单元/多级浮选竭力降低成本(如能源消耗、污泥产生量和污泥处理、过程运行性能),并在脱墨车间和造纸厂探寻浮选脱墨技术的新应用.

关键词：摘要编辑部编辑工作读者

Oxidation behavior and improvement in nonflammability of LPSO-type Mg–Zn–Y–Sr alloy

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Journal of Magnesium and Alloys 2024年第2期12卷 742-749页

作者： Shin-ichi Inoue Kazumasa Iwanaga Yoshihito Kawamura Magnesium Research Center Kumamoto University2-39-1 KurokamiChuo-kuKumamoto 860-8555Japan Department of Materials Science Graduate School of Science and TechnologyKumamoto University2-39-1 KurokamiChuo-kuKumamoto 860-8555Japan

Mg_(97)Zn_(1)Y_(2)alloys with high ignition temperatures were developed by adding *** addition of Sr resulted in the formation of a uniform and thin Y_(2)O_(3)***–Zn–Y alloys containing at least 0.25 at.%Sr exhibited ignition temperatures of 1270–1320 *** a result of EDS measurement,Sr was found to be concentrated in the Y_(2)O_(3)*** addition,a mixed film of MgO and Sr O formed on the outer layer in the 1.5 at.%Sr-containing Mg_(97)Zn_(1)Y_(2)*** findings suggest that the uniform and thin Y_(2)O_(3)film that maintains high soundness at high temperatures was formed owing to valence control and the formation of a protective outer oxide film.

关键词： Magnesium alloy Yttrium Strontium High-temperature oxidation Nonflammability

Time-consistent pension policy with minimum guarantee and sustainability constraint

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Probability, Uncertainty and Quantitative Risk 2024年第1期9卷 35-64页

作者： Caroline Hillairet Sarah Kaakar Mohamed Mrad CREST UMR CNRS 9194ENSAEInstitut Polytechnique de ParisFrance LMM Institut du Risque et de I'AssuranceLe Mans UniversiteFrance LAGA UMR CNRS 7539Universite Sorbonne Paris NordFrance

This paper proposes and investigates an optimal pair investment/pension policy for a pay-as-you-go(PAYG)pension *** social planner can invest in a buffer fund in order to guarantee a minimal pension *** model aims at taking into account complex dynamic phenomena such as the demographic risk and its evolution over time,the time and age dependence of agents preferences,and financial *** preference criterion of the social planner is modeled by a consistent dynamic utility defined on a stochastic domain,which incorporates the heterogeneity of overlapping generations and its evolution over *** preference criterion and the optimization problem also incorporate sustainability,adequacy and fairness *** paper designs and solves the social planner's dynamic decision criterion,and computes the optimal investment/pension policy in a general framework.A detailed analysis for the case of dynamic power utilities is provided.

关键词： Consistent dynamic utility PAYG pension policy Sustainability and actuarial fairness Demographic and financial risk sharing Stochastic control