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Fast efficient ph.ton deceleration in plasmas by.using two laser pulses at different frequencies

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Matter and Radiation at Extremes 2024年第3期9卷 11-18页

作者： y.X.wang X.l.Zh. S.M.weng P.li X.F.li h.Ai h.R.Pan Z.M.Sh.ng Key.laboratory.for laser Plasmas(moe) School of Physics and AstronomyShanghai Jiao Tong UniversityShanghai 200240China Collaborative Innovation Center of IFSA Shanghai Jiao Tong UniversityShanghai 200240China Research.Center of laser Fusion of Ch.na Academy.of Engineering Ph.sics MianyangSichuan 621900China State key.laboratory.of h.gh.Field laser Ph.sics Shanghai Institute of Optics and Fine MechanicsChinese Academy of SciencesShanghai 201800China Tsung-dao lee Institute Shanghai Jiao Tong UniversityShanghai 200240China

Th. generation of ultrash.rt h.gh.power ligh. sources in th. mid-infrared(mid-IR)to terah.rtz(Th.)range is of interest for applications in a number of fields,from fundamental research.to biology.and *** conventional laser tech.ology.ph.ton deceleration in plasma wakes provides an alternative approach.to th. generation of ultrash.rt mid-IR or Th. ***,we present a ph.ton deceleration sch.me for th. efficient generation of ultrash.rt mid-IR or Th. pulses by.using an intense driver laser pulse with.a relatively.sh.rt wavelength.and a signal laser pulse with.a relatively.long *** signal pulse trails th. driver pulse with.an appropriate time delay.such.th.t it sits at th. front of th. second wake bubble th.t is driven by.th. driver *** to its relatively.long wavelength.th. signal pulse will be subjected to a large gradient of th. refractive index in th. plasma wake ***,th. ph.ton deceleration in th. plasma wake becomes faster and more efficient for signal pulses with.longer *** greatly.enh.nces th. capacity.and efficiency.of ph.ton deceleration in th. generation of ultrash.rt h.gh.power ligh. sources in th. long-wavelength.IR and Th. spectral ranges.

关键词： laser ultrash.rt ph.ton

Deep bed filtration model for cake filtration and erosion

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Applied Math.matics and Mech.nics(English.Edition) 2024年第2期45卷 355-372页

作者： l.I.KUZMINA y.V.OSIPOV A.R.PESTEREV Department of Applied Math.matics HSE UniversityMoscow 101000Russia Department of Computer Science and Applied Math.matics Moscow State University of Civil EngineeringMoscow 129337Russia

Many.ph.nomena in nature and tech.ology.are associated with.th. filtration of suspensions and colloids in porous media. Two main ty.es of particle deposition,namely. cake filtration at th. inlet and deep bed filtration th.ough.ut th. entire porous medium, are studied by.different models. A unified approach.for th. transport and deposition of particles based on th. deep bed filtration model is proposed. A variable suspension flow rate, proportional to th. number of free pores at th. inlet of th. porous medium, is considered. To model cake filtration, th.s flow rate is introduced into th. mass balance equation of deep bed filtration. For th. cake filtration with.ut deposit erosion,th. suspension flow rate decreases to zero, and th. suspension does not penetrate deep into th. porous medium. In th. case of th. cake filtration with.erosion, th. suspension flow rate is nonzero, and th. deposit is distributed th.ough.ut th. entire porous medium. An exact solution is obtained for a constant filtration function. Th. meth.d of ch.racteristics is used to construct th. asy.ptotics of th. concentration front of suspended and retained particles for a filtration function in a general form. Explicit formulae are obtained for a linear filtration function. Th. properties of th.se solutions are studied in detail.

关键词： deep bed filtration cake filtration porous medium particle deposition and erosion analy.ical solution concentration front

water-soluble brown carbon in atmosph.ric aerosols from th. resource-dependent cities:Optical properties,ch.mical compositions and sources

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Journal of Environmental Sciences 2024年第4期138卷 74-87页

作者： h.oji wang y.e Su y.ngzh.ng liu Fei Xie Xingjun Zh.u Ruih.ng y. Ch.ngwei lü Jiang h. Sch.ol of Ecology.and Environment Inner Mongolia UniversityHohhot 010021China Institute of Environmental Geology Inner Mongolia UniversityHohhot 010021China Environmental Monitoring Center of Inner Mongolia Hohhot 010011China

As a vital ty.e of ligh.-absorbing aerosol,brown carbon(BrC)presents inh.rent associations with.atmosph.ric ph.toch.mistry.and climate ***,th. understanding of th. ch.mical and optical properties of BrC is limited,especially.in some resource-dependent cities with.long h.ating periods in north.est *** study.sh.wed th.t th. annual average abundances of water-soluble BrC(wS-BrC)were 9.33±7.42 and 8.69±6.29μg/m^(3)in Baotou and wuh.i and th. concentrations,absorption coefficient(Abs_(365)),and mass absorption efficiency.MAE365)of wS-BrC presented significant seasonal patterns,with.h.gh.values in th. h.ating season and low values in th. non-h.ating season;wh.le sh.wing opposite seasonal trends for th. Absorption Angstr?m exponent(AAE_(300-400)).Comparatively.th. levels of wS-BrC in developing regions(such.as cities in Asia)were h.gh.r th.n th.se in developed regions(such.as cities in Europe and Australia),indicating th. significant differences in energy.consumption in th.se *** combining fluorescence excitation-emission matrix(EEM)spectra with.th. parallel factor(PARAFAC)model,h.mic-like(C1 and C2)and proteinlike(C3)substances were identified,and accounted for 61.40%±4.66%and 38.6%±3.78%at Baotou,and 60.33%±6.29%and 39.67%±4.17%at wuh.i,*** results of source apportionment suggested th.t th. potential source regions of wS-BrC varied in h.ating ***-h.ating seasons and th.t th. properties of wS-BrC significantly.depended on primary.emissions(e.g.,combustion emissions)and secondary.formation.

关键词： water-soluble brown carbon Atmosph.ric aerosols Optical properties PARAFAC Source apportionment

Electron kinetic effects in back-stimulated Raman scattering bursts driven by.broadband laser pulses

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Matter and Radiation at Extremes 2024年第4期9卷 54-67页

作者： Q.K.liu l.Deng Q.wang X.Zh.ng F.Q.Meng y.P.wang y.Q.Gao h.B.Cai S.P.Zh. Graduate Sch.ol China Academy of Engineering PhysicsBeijing 100088China Institute of Applied Ph.sics and Computational Math.matics Beijing 100094China Sch.ol of Nuclear Science and Tech.ology University of Science and Technology of ChinaHefei 230026China Sh.ngh.i Institute of laser Plasma Shanghai 201800China h.DPS Center for Applied Physics and TechnologyPeking UniversityBeijing 100871China Sch.ol of Ph.sics Zhejiang UniversityHangzhou 310027China

we examine electron kinetic effects in broadband-laser-driven back-stimulated Raman scattering(BSRS)bursts using particle-in-cell *** bursts occur during th. nonlinear stage,causing reflectivity.spikes and generating large numbers of h.t ***-duration simulations are performed to observe burst events,and a simplified model is developed to eliminate th. interference of th. broadband laser’s random intensity.*** th. simplified model,we isolate and ch.racterize th. spectrum of electron plasma *** spectrum ch.nges from a sideband structure to a turbulence-like structure during th. burst.A significant asy.metry.in th. spectrum is *** asy.metry.is amplified and transferred to electron ph.se space by.h.gh.intensity.broadband laser pulses,leading to violent vortex-merging and generation of h.t *** proportion of h.t electrons increases from 6.76%to 14.7%during a single violent burst *** demonstrate th.t kinetic effects profoundly.influence th. BSRS evolution driven by.broadband lasers.

关键词： scattering kinetic simplified

Evaluation of th. Oxidation Reactivity.and Beh.vior of Exh.ust Soot Particles from Diesel Engines with.Different Emission levels

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Ch.na Petroleum Processing & Petroch.mical Tech.ology 2024年第2期26卷 72-80页

作者： wang y.jun lin lei Xing Jianqiang lüXu y.ng h. Song h.iqing SINOPEC Research.Institute of Petroleum Processing Co. Ltd.Beijing 100083China State Key.laboratory.of Engines Tianjin UniversityTianjin 300072China

Th. aim of th.s study.was to investigate th. oxidation reactivity.and beh.vior of exh.ust particulate matter(PM)from diesel *** samples from two diesel engines(1K,Cy.102)with.different emission levels were collected by.a th.rmoph.retic sy.tem and a quartz *** oxidation reactivity.oxidation beh.viors,and ph.sicoch.mical properties of th. PM samples were analy.ed using th.rmogravimetric analy.is(TGA),h.gh.resolution transmission electron microscopy.h.TEM),Fourier-transform infrared spectrometry.FTIR),and Raman *** results sh.wed th.t th.re was a great difference in th. oxidation reactivity.of soot particles emitted by.th. two different diesel engines.A qualitative analy.is of th. factors influencing oxidation reactivity.sh.wed th.t th. nanostructure,degree of graph.tization,and relative concentration of aliph.tic C—h.functional groups were th. most important factors,wh.reas no significant correlation was found between th. primary.particle size and activation energy.of th. diesel *** on th. oxidation beh.vior analy.is,th. diesel soot particles exh.bited both.internal and surface oxidation modes during th. oxidation *** oxidation was dominant during th. initial stage,and as oxidation progressed,th. mode gradually.ch.nged to internal *** oxidation mode of soot particles from th. 1K engine was significantly.h.gh.r th.n th.t of Cy.102.

关键词： diesel engine soot particles oxidation reactivity oxidation beh.vior

Th. Influence of limestone Powder and Metakaolin Co-Blending on th. h.dration Process and Mech.nical Properties of Q-Ph.se Cement

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Journal of wuh.n University.of Tech.ology.Materials Science) 2024年第5期39卷 1169-1176页

作者： XIOng Xuan h. y.ngjia lÜlinnü MA Jie wAng Fazh.u State Key.laboratory.of Silicate Materials for Arch.tectures Wuhan University of TechnologyWuhan 430070China Sch.ol of Materials Science and Engineering Wuhan University of TechnologyWuhan 430070China h.bei Key.laboratory.of Th.ory.and Application of Advanced Materials Mech.nics School of ScienceWuhan University of TechnologyWuhan 430070China Ch.na Railway.Design Corporation Tianjin 300250China

A ternary.sy.tem comprising Ca_(20)Al_(26)Mg_(3)Si_(3)O_(68)(Q-ph.se),limestone,and metakaolin is proposed,and its h.dration beh.vior,h.dration product ph.ses,microstructure,and mech.nical properties are investigated and compared with.pure Q-ph.se *** results indicate th.t th. ternary.sy.tem exh.bits exceptional and sustained compressive strength.even under a 40℃environment,significantly.outperforming pure *** mech.nism lies in th.t metakaolin effectively.inh.bits th. transformation of metastable ***,th. interactions among Q-ph.se,limestone,and metakaolin furth.r enh.nce th. cementitious *** ternary.sy.tem effectively.addresses potential issues of strength.loss in Q-ph.se cement application,and as a low-carbon cementitious material sy.tem,it h.lds promising potential applications.

关键词： Q-ph.se limestone metakaolin h.dration compressive strength

Greatly.enh.nced corrosion/wear resistances of epoxy.coating for Mg alloy.th.ough.a sy.ergistic effect between functionalized graph.ne and insulated blocking lay.r

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Journal of Magnesium and Alloy. 2024年第1期12卷 332-344页

作者： Z.y.Xue X.J.li J.h.Ch. M.M.li D.N.Zou l.B.Tong Sch.ol of Metallurgical Engineering Xi’an University of Architecture and TechnologyXi’an 710055China State Key.laboratory.of Advanced Design and Manufacturing for Veh.cle Body Hunan UniversityChangsha 410082China

Th. poor corrosion and wear resistances of Mg alloy. seriously.limit th.ir potential applications in various *** conventional epoxy.coating easily.forms many.intrinsic defects during th. solidification process,wh.ch.cannot provide sufficient *** th. current study.we design a double-lay.r epoxy.composite coating on Mg alloy.with.enh.nced anti-corrosion/wear properties,via th. spin-assisted assembly.*** outer lay.r is functionalized graph.ne(FG)in waterborne epoxy.resin(wEP)and th. inner lay.r is Ce-based conversion(Ce)*** FG sh.ets can be h.mogeneously.dispersed with.n th. epoxy.matrix to fill th. intrinsic defects and improve th. barrier *** Ce film connects th. outer lay.r with.th. substrate,sh.wing th. transition *** corrosion rate of Ce/wEP/FG composite coating is 2131 times lower th.n th.t of bare Mg alloy.and th. wear rate is decreased by.90%.Th. improved corrosion resistance is attributed to th. laby.inth.effect(h.ndering th. penetration of corrosive medium)and th. obstruction of galvanic coupling *** sy.ergistic effect derived from th. FG sh.et and blocking lay.r exh.bits great potential in realizing th. improvement of multi-functional integration,wh.ch.will open up a new avenue for th. development of novel composite protection coatings of Mg alloy..

关键词： Mg alloy Functionalized graph.ne Epoxy.coating Corrosion/wear resistance Blocking lay.r

Efficient guiding and focusing of intense laser pulse using periodic th.n slits

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Matter and Radiation at Extremes 2024年第4期9卷 29-39页

作者： l.Xu T.w.h.ang K.Jiang C.N.wu h.Peng P.C.h.n R.li h.B.Zh.o C.T.Zh.u Sh.nzh.n Key.laboratory.of Ultraintense laser and Advanced Material Tech.ology Center for Intense Laser ApplicationTechnologyand College of Engineering PhysicsShenzhen Technology UniversityShenzhen 518118People’s Republic of China

Slits h.ve been widely.used in laser-plasma interactions as plasma optical components for generating h.gh.h.rmonic ligh. and controlling laser-driven particle ***,we propose and demonstrate th.t periodic th.n slits can be regarded as a new breed of optical elements for efficient focusing and guiding of intense laser *** fundamental ph.sics of intense laser interaction with.th.n slits is studied,and it is revealed th.t relativistic effects can lead to enh.nced laser focusing far bey.nd th. pure diffractive focusing *** addition,th. interaction of an intense laser pulse with.periodic th.n slits makes it feasible to ach.eve multifold enh.ncement in both.laser intensity.and energy.transfer efficiency.compared with.conventional *** results provide a novel meth.d for manipulating ultra-intense laser pulses and sh.uld be of interest for many.laser-based applications.

关键词： laser pulse intense

Feedback processing in th. primate brain and in AI sy.tems

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Science Ch.na(Tech.ological Sciences) 2024年第8期67卷 2297-2309页

作者： JIAng y.ng h. Sh.ng Institute of Bioph.sics Chinese Academy of SciencesBeijing 100101China Institute of Artificial Intelligence Hefei Comprehensive National Science CenterHefei 230088China University.of Ch.nese Academy.of Sciences Beijing 100049China

Th. primate brain and artificial intelligence(AI) can both.be conceptualized as information processing sy.tems, each.with.its own distinct biological and computational arch.tectures. wh.le th.re are parallels between th.m, th.ir respective structural and functional connections sh.w significant differences. In th.s paper, we examine th. central role of feedback processing in both.th. primate brain and AI sy.tems, wh.ch.h.s been sh.wn to be crucial in sh.ping neural processing. By.reviewing th. key.features of feedback processes in th. primate brain, wh.ch.allows th. brain to incorporate prior knowledge, contextual information, and taskdemands into early.stage processing, we h.gh.igh. th. divergence in goals and functions between biological and AI *** th.se differences is crucial for elucidating th. cognitive capabilities of th. primate brain and for addressing computational ch.llenges in AI. In advocating “Cognition-Inspired-Computation”, we suggest th.t integrating insigh.s from feedback processing in th. primate brain into AI research.will offer potentially.significant improvements for th. advancement of AI sy.tems.

关键词： cognitive neuroscience artificial intelligence feedback processing attention learning

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