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Sy.chronized off-harmonic probe laser with highly.variable pulse duration for laser-plasma interaction experiments

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High Power Laser Science and Engineering 2024年第1期12卷 99-107页

作者： J.Hornung y.Zobus H.Lorenté C.Brabetz B.Zielbauer V.Bagnoud GSI Helmholtzzentrum für Schwerionenforschung GmbH DarmstadtGermany Institut d’Optique UniversitéParis-SaclayPalaiseauFrance Institut für Angewandte Phy.ik Technische Universität DarmstadtDarmstadtGermany

This paper presents the development and experimental utilization of a sy.chronized off-harmonic laser sy.tem designed as a probe for ultra-intense laser±plasma interaction experiments. The sy.tem exhibits a novel seed-generation design,allowing for a variable pulse duration spanning over more than three orders of magnitude, from 3.45 picoseconds to 10 nanoseconds. This makes it suitable for various plasma diagnostics and visualization techniques. In a side-view configuration, the laser was employ.d for interferometry.and streaked shadowgraphy.of a laser-induced plasma while successfully.suppressing the self-emission background of the laser±plasma interaction, resulting in a signal-to-self-emission ratio of 110 for this setup. These properties enable the probe to y.eld valuable insights into the plasma dy.amics and interactions at the PHELIX facility.and to be deploy.d at various laser facilities due to its easy.to-implement design.

关键词： interferometry laser-plasma interaction off-harmonic probe laser streaked shadowgraphy

Microstructure evolution and shape memory.behaviors of Ni_(47)Ti_(44)Nb_(9)alloy.subjected to multistep thermomechanical loading with different prestrain levels

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Journal of Materials Science & Technology 2024年第4期171卷 80-93页

作者： y.H.Zhang H.Li Z.W.y.ng X.Liu Q.F.Gu State Key.Laboratory.of Solidification Processing School of Materials Science and EngineeringNorthwestern Polytechnical UniversityXi’an 710072China Shaanxi Key.Laboratory.of High-Performance Precision Forming Technology.and Equipment Northwestern Polytechnical UniversityXi’an 710072China

Ni_(47)Ti_(44)Nb_(9)shape memory.alloy.SMA)is a promising material in the aerospace field due to its wide transformation *** application of shape memory.effect depends on multistep thermomechan-ical loading,viz.,low-temperature deformation and subsequent heating to ***-temperature deformation prestrain play. a pivotal role in shape memory.properties tailoring of SMA ***,microstructure evolution and deformation mechanisms of Ni_(47)Ti_(44)Nb_(9)SMA subjected to vari-ous prestrain levels are still *** this end,microstructure evolution and shape memory.behaviors of Ni_(47)Ti_(44)Nb_(9)alloy.subjected to multistep thermomechanical loading with prestrain levels of 8%-16%at-28℃(M_(s)+30℃)were *** results demonstrate that the stress-strain curve of the specimen exhibits four distinct stages at a maximal prestrain of 16%.Whereas stageⅡand stageⅢend at prestrains of∼8%and∼12%,*** stageⅡ,the stress-induced martensitic transformation is accompanied by.the dislocation slip of the NiTi matrix andβ-Nb *** stageⅢ,in addition to the higher density.of dislocations and further growth of stress-induced martensite variants(SIMVs),(001)compound twins are introduced as a result of the(001)deformation twinning in stress-induced ***{20-1}martensite twins are gradually.introduced in stageⅣ.Correspondingly.after subsequent unloading and heating,a higher density.of{114}austenite twins form in the specimen with a larger prestrain of 16%.With increasing prestrain from 8%to 16%,the recoverable strainε_(re)^(T)upon heating increases first and then ***ε_(re)^(T)obtains a maximum of 7.03%at 10%prestrain and de-creases to 6.17%at 16%*** increase ofε_(re)^(T)can be attributed to the formation of new SIMVs,the further growth of existing SIMVs,and the recoverable(001)compound *** the decrease ofε_(re)^(T)is mainly.associated with the irrecoverable strain by.20−1}martensite *** effe

关键词： Ni_(47)Ti_(44)Nb_(9)shape memory.alloy Wide transformation hy.teresis Thermomechanical loading Microstructure evolution Shape memory.behaviors Stress-induced martensitic transformation Deformation twinning

Recent Advances in Computational Simulation of Macro-,Meso-,and Micro-Scale Biomimetics Related Fluid Flow Problems

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Journal of Bionic Engineering 2007年第2期4卷 97-107页

作者： y. y. y.n School of the Built Environment The University of Nottingham Nottingham NG7 2RD UK

Over the last decade, computational methods have been intensively.applied to a variety.of scientific researches and engineering designs. Although the computational fluid dy.amics （CFD） method has play.d a dominant role in study.ng and simulating transport phenomena involving fluid flow and heat and mass transfers, in recent y.ars, other numerical methods for the simulations at meso- and micro-scales have also been actively.applied to solve the phy.ics of complex flow and fluid-interface interactions. This paper presents a review of recent advances in multi-scale computational simulation of biomimetics related fluid flow problems. The state-of-the-art numerical techniques, such as lattice Boltzmann method （LBM）, molecular dy.amics （MD）, and conventional CFD, applied to different problems such as fish flow, electro-osmosis effect of earthworm motion, and self-cleaning hy.rophobic surface, and the numerical approaches are introduced. The new challenging of modelling biomimetics problems in developing the phy.ical conditions of self-clean hy.rophobic surfaces is discussed.

关键词： biomimetics computational simulation macro- meso- micro-scale hy.rophobic surfaces

Four Late-ty.e Galaxies with Double Radio Lobes and Properties of Such Galaxies

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Research in Astronomy.and Astrophy.ics 2024年第4期24卷 84-90页

作者： Z.S.y.an X.y.Gao Z.L.Wen J.L.Han National Astronomical Observatories Chinese Academy of SciencesBeijing 100101China CAS Key.Laboratory.of FAST National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100101China School of Astronomy.and Space Sciences University of Chinese Academy of SciencesBeijing 100049China

The triggering mechanism for radio lobes from late-ty.e galaxies is not fully.*** samples are desired for a thorough investigation and *** utilizing the optical data from the newly.released Dark Energy.Spectroscopic Instrument imaging survey. and the radio sources from the NRAO VLA Sky.Survey.and the Faint Images of the Radio Sky.at Twenty.centimeter,we identify.four Late-ty.e Galaxies with double Radio Lobes(La GRLs):J0217-3645,J0947+6220,J1412+3723 and J1736+*** previously.known La GRLs,we confirm the correlation between radio power P_(1.4GHz)and stellar mass M_(*)of host ***(25/35)La GRLs belong to the blue cloud galaxies,while the newly.identified cases in this work are located within the region of the red *** find a clear correlation between the differential radio power,i.e.,the offset from the P_(1.4GHz)-M_(*)relation,and the galaxy.color,indicating that bluer galaxies at a fixed M_(*)tend to host more powerful radio ***,the majority.31/36)of La GRLs are either located in a galaxy.group or display.ng a disturbed *** suggest that all of the galaxy.mass,color and surrounding environment could play.important roles in triggering radio lobes in late-ty.e galaxies.

关键词： galaxies:active galaxies:jets galaxies:spiral radio continuum:galaxies

Dy.amics of Plate Equations with Memory.Driven by.Multiplicative Noise on Bounded Domains

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Journal of Applied Mathematics and Phy.ics 2024年第4期12卷 1492-1521页

作者： Mohamed y. A. Bakhet Abdelmajid Ali Dafallah Jing Wang Qiaozhen Ma Fadlallah Mustafa Mosa Ahmed Eshag Mohamed Paride O. Lolika Makur Mukuac Chinor School of Mathematics University of Juba Juba South Sudan Department of Mathematics Faculty of Petroleum and Hydrology Engineering Alsalam University Almugled Sudan College of Mathematics and Statistics Northwest Normal University Lanzhou China Department of Mathematics and Phy.ics Faculty of Education University of Kassala Kassala Sudan Department of Mathematics School of Education University of Juba Juba South Sudan

This article examines the dy.amics for stochastic plate equations with linear memory.in the case of bounded domain. We investigate the existence of solutions and bounded absorbing set by.using the uniform pullback attractors on the tails estimates, and the asy.ptotic compactness of the random dy.amical sy.tem is proved by.decomposition method, and then we obtain the existence of a random attractor.

关键词： Plate Equations Random Attractors Memory.Term Dy.amical Sy.tems

Finite element analy.is and experimental validation of poly.er-metal contacts in block-on-ring configuration

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Friction 2024年第3期12卷 554-568页

作者： K.y.Eay.l AWWAD Khosro FALLAHNEZHAD B.F.y.USIF Ahmad MOSTAFA Omar ALAJARMEH A.SHALWAN Xuesen ZENG Mechanical Engineering Department Faculty of EngineeringTafila Technical UniversityTafila 66110Jordan Medical Device Research Institute College of Science and EngineeringFlinders UniversitySouth Australia 5042Australia Centre for Future Materials University of Southern QueenslandToowoomba 4350Australia Department of Manufacturing Engineering Technology Public Authority for Applied Education and TrainingKuwait 13092Kuwait

The wear profile analy.is,obtained by.different tribometers,is essential to characterise the wear ***,most of the available methods did not take the stress distribution over the wear profile in consideration,which causes inaccurate *** this study.the wear profile of poly.er–metal contact,obtained by.block-on-ring configuration under dry.sliding conditions,was analy.ed using finite element modelling(FEM)and experimental ***’s wear equation was integrated into a developed FORTRAN-UMESHMOTION code linked with Abaqus software.A vary.ng wear coefficient(k)values covering both running-in and steady.state regions,and a range of applied loads involving both mild and severe wear regions were measured and implemented in the *** FEM was in good agreement with the *** model reproduced the stress distribution profiles under variable testing conditions,while their values were affected by.the sliding direction and maximum wear depth(hmax).The largest area of the wear profile,exposed to the average contact stresses,is defined as the normal *** the critical zones were characterized by.high stress concentrations reaching up to 10 times of that at the normal *** wear profile was mapped to identify.the critical zone where the stress concentration is the key.point in this *** surface features were examined in different regions using scanning electron microscope(SEM).Ultimately.SEM analy.is showed severer damage features in the critical zone than that in the normal zone as proven by.***,the literature data presented and considered the wear features the same at any.point of the wear *** this study.the normal zone was determined at a stress value of about 0.5 MPa,whereas the critical zone was at about 5.5 *** wear behaviour of these two zones showed totally.different features from one another.

关键词： poly.er-to-metal contact block-on-ring wear profile wear model

Resistive field generation in intense proton beam interaction with solid targets

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Matter and Radiation at Extremes 2024年第1期9卷 35-43页

作者： W.Q.Wang J.J.Honrubia y.y.n X.H.y.ng F.Q.Shao Department of Phy.ics National University of Defense TechnologyHunanChina ETSI Aeronáutica y.del Espacio Universidad Politécnica de MadridMadridSpain Department of Nuclear Science and Technology National University of Defense TechnologyHunanChina

The Brown-Preston-Singleton(BPS)stopping power model is added to our previously.developed hy.rid code to model ion beam-plasma *** simulations show that both resistive field and ion scattering effects are important for proton beam transport in a solid target,in which they.compete with each *** the target is not completely.ionized,the self-generated resistive field effect dominates over the ion scattering ***,when the target is completely.ionized,this situation is ***,it is found that Ohmic heating is important for higher current densities and materials with high *** energy.fraction deposited as Ohmic heating can be as high as 20%-30%.Ty.ical ion divergences with half-angles of about 5°-10°will modify.the proton energy.deposition substantially.and should be taken into account.

关键词： interaction beam intense

Editorial for Multiscale&Multifield Coupling in Geomechanics

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第6期16卷 1919-1921页

作者： Min Wang Pengzhi Pan Andrew H.C.Chan y.T.Feng T-3 Fluid Dy.amics and Solid Mechanics Theoretical DivisionLos Alamos National LaboratoryNew MexicoUSA Institute of Rock and Soil Mechanics Chinese Academy of SciencesWuhanChina School of Engineering University of TasmaniaTasmaniaAustralia College of Engineering Swansea UniversityWalesUK

We are delighted to serve as guest editors for this special issue in the Journal of Rock Mechanics and Geotechnical *** purpose of this special issue is dedicated to gathering the latest research work on Multiscale&Multifield Coupling in Geomechanics,where we delve into the intricate interplay.of various fields and scales that govern the behavior of *** total,30 manuscripts from USA,China,UK,Germany.Canada,India and United Arab Emirates are selected to be included in this issue.

关键词： materials. gathering mechanics

On the extension of L^2 holomorphic functions VII： Hy.ersurfaces with isolated singularities

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Science China Mathematics 2017年第6期60卷 1083-1088页

作者： ohsawa Takeo Graduate School of Mathematics Nagoya University Nagoya 464-8602 Japan

An extension theorem for holomorphic functions with L^2 growth condition is strengthened for the case of the extension from hy.ersurfaces with isolated singularities.

关键词： L^2 holomorphic hy.ersurface isolated singularity