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Effect of differ.nt w.ter.supply on mor.hology, gr.w.h and physiological char.cter.stics of Salix psammophila seedlings in Maow.su sandland, China

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Jour.al of Envir.nmental Sciences 2001年第4期13卷 411-417页

作者： Xiao, C.-w. Lab. Quantitative Vegetation Ecol. Institute of Botany Chinese Academy of Sciences Beijing 100093 China

r.sponse patter. w.s investigated for.seedlings of Salix psammophila, a dominant shr.b in Maow.su sandland, to the simulated pr.cipitation change by ar.ificially contr.lling w.ter.supply at four.levels. The gr.w.h char.cter., in ter.s of plant height, stem diameter. total br.nch number. total leaf number.and ar.a, total bifur.ation r.tio, total br.nch lenght and br.nch number. br.nch lenght, leaf number.and leaf ar.a of each br.nch or.er. and leaf, br.nch and r.ot biomass significantly incr.ased w.en w.ter.supply incr.ased. That w.ter.supply had significant effect on biomass allocation show.d differ.nt investment patter. of biomass r.sour.e of the seedlings gr.w. under.differ.nt w.ter.supply tr.atments. Stomatal density of abaxial leaf sur.ace decr.ased, and stomatal appar.tus length and w.dth of adaxial and abaxial leaf sur.ace incr.ased w.th the incr.ase of w.ter.supply, w.ile Stomatal density of adaxial leaf sur.ace w.s not affected by w.ter.supply. w.ter.supply obviously affected the diumal changes of photosynthetic r.te, and the photosynthetic r.te of the seedlings show.d str.ngly midday depr.ssion gr.w. under.the 157.5 mm w.ter.supply, but not gr.w. under.higher.w.ter.supply. Additionally the assimilation-light r.sponse cur.es and flour.scence efficiency mor. show.d that w.ter.supply impr.ve photosynthesis capacity. Finally, S. psammophila seedlings stood out by their.slow.gr.w.h and r.latively high investments in r.ot gr.w.h in or.er.to r.duce tissue losing r.te and consumption of w.ter.r.sour.e for.keeping w.ter.balance under.w.ter.str.ss. The seedlings that gr.w. under.r.ch w.ter.supply did by their.fast gr.w.h and r.latively high investments in br.nch and leaf gr.w.h in or.er.to impr.ve the pow.r.of captur.ng light ener.y for.higher.photosynthesis.

关键词： Biomass Fluor.scence Mor.hology Photosynthesis Physiology Plants (botany) Pr.cipitation (chemical) Seed Tissue

Fir.t-Pr.nciples Study of the Influence of Lattice Misfit on the Behavior.and the Ductility Effect of Hafnium in Ni-Ni3AI System

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Acta Metallur.ica Sinica(English Letter.) 2014年第1期27卷 87-94页

作者： Y. w. J. Guo w. Zhang X. Ma Q. Zhang J. Hou r. Huang X. Liu Institute of Molecular.Engineer.ng and Applied Chemistr. Anhui University of Technology Ma'anshan 243002 China Shenyang National Labor.tor. for.Mater.als Science Instituteof Metal Research Chinese Academy of SciencesShenyang 110016 China College of Physics Science and Technology Shenyang NormalUniversity Huanghe Street 253 Shengyang 110034 China School of Mater.als Science and Engineer.ng Anhui Universityof Technology Ma'anshan 243002 China

Tw. Ni/Ni3Al-inter.ace-contained cluster.models w.th/w.thout lattice misfit ar. studied by fir.t-pr.nciples method to clar.fy the debates about the segr.gation behavior. of Hafnium （Hf） and explor. the influence of lattice misfit on the ductility effect of Hr. It is found that though Hf pr.fer. to substitute A1 r.ther.than Ni in Ni3A1 phase w.thin most of the investigated misfit r.nge, its str.nger.pr.fer.ing to Ni phase than NiaA1 phase makes it impossible to go into Ni3A1 phase to occupy A1 site in Ni-Ni3A1 alloys. Bond or.er.analysis in Hf-fr.e case show. that lattice misfit has differ.nt effects on the Gr.ffith w.r. of inter.acial cleavage 27int/E and the maximum theor.tical shear.str.ss Zmax of Ni and Ni3A1, contr.buting to the existence of anomalous str.ngth-temper.tur. phenomena in NiaA1 alloys. How.ver. the addition of Hf w.ll make the 27int/E （or.Zmax） of both Ni3A1 and Ni decr.ase （or.incr.ase） w.th lattice misfit, indicating that the addition of Hf may make the anomalous str.ngth-temper.tur. r.lationship in Ni3A1 r.gion disappear.locally.

关键词： Hafnium Lattice misfit Segr.gation Ductility

Super.lasticity of Ti2448 Alloy w.th Nanostr.ctur.d Gr.ins

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Jour.al of Mater.als Science & Technology 2011年第12期27卷 1099-1104页

作者： M.J. Xiao Y.X. Tian G. w. Mao S.J. Li Y.L. Hao r. Yang School of Astr.nautics Northwestern Polytecllnic University Xi＇an 710072 China - Shenyang National Labor.tor. for.Mater.als Science Institute of Metal Research Chinese Academy of Sciences Shenyang 110016 China

Ti-24Nb-4Zr.8Sn, abbr.viated as Ti2448 fr.m its chemical composition in w.ight per.ent, is a multifunctional /3 type titanium alloy w.th body center.d cubic （bcc） cr.stal str.ctur., and its highly localized plastic defor.ation behavior.contr.butes significantly to gr.in r.finement dur.ng conventional cold pr.cessing. In the paper. the nanostr.ctur.d （NS） alloy w.th gr.in size less than 50 nm pr.duced by cold r.lling has been used to investigate its super.lastic defor.ation behavior.by uniaxial tensile tests at initial str.in r.tes of 1.5 ×10-2, 1.5×10^-3 and 1.6×10-4 s-1 and temper.tur.s of 600,650 and 700℃. The r.sults show.that, in compar.son w.th the coar.e-gr.ined alloy w.th size of 50 μm, the NS alloy has better.super.lasticity w.th elongation up to ～275% and ultimate str.ngth of 50-100 MPa. Str.in r.te sensitivity （m） of the NS alloy is 0.21, 0.30 and 0.29 for.600,650 and 700℃, r.spectively. These r.sults demonstr.te that gr.in r.finement is a valid w.y to enhance the super.lasticity of Ti2448 alloy.

关键词： Titanium alloy bcc cr.stal Super.lasticity Nanostr.ctur.d gr.in

Scalable Ir.Doped NiFe_(2)O_(4)/TiO_(2)Heter.junction Anode for.Decentr.lized Saline w.stew.ter.Tr.atment and H_(2)Pr.duction

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Nano-Micr. Letter. 2025年第3期17卷 1-18页

作者： Sukhw. Hong Jiseon Kim Jaebeom Par. Sunmi Im Michael r.Hoffmann Kangw.o Cho Division of Envir.nmental Science and Engineer.ng Pohang University of Science and Technology(POSTECH)Pohang 790−784Korea Linde Labor.tor. California Institute of TechnologyPasadenaCA 91125USA Institute for.Conver.ence r.sear.h and Education in Advanced Technology(I‑Cr.ATE) Yonsei University International CampusIncheon 21983Republic of Korea

w.stew.ter.electr.lysis cells(w.Cs)for.decentr.lized w.stew.ter.tr.atment/r.use coupled w.th H_(2)pr.duction can r.duce the car.on footpr.nt associated w.th tr.nspor.ation of w.ter.w.ste,and ener.y *** study r.por.s Ir.doped NiFe_(2)O_(4)(NFI,~5 at%Ir.spinel layer.w.th TiO_(2)over.ayer.NFI/TiO_(2)),as a scalable heter.junction anode for.dir.ct electr.lysis of w.stew.ter.w.th cir.umneutr.l pH in a single-compar.ment *** dilute(0.1 M)NaCl solutions,the NFI/TiO_(2)mar.s super.or.activity and selectivity for.chlor.ne evolution r.action,outper.or.ing the benchmar. Ir._(2).r.bust oper.tion in near.neutr.l pH w.s *** including oper.ndo X-r.y absor.tion spectr.scopy unveiled cr.cial r.les of TiO_(2) w.ich ser.es both as the pr.mar. site for.Cl−chemisor.tion and a pr.tective layer.for.NFI as an ohmic *** electr.lysis of NH4+-laden synthetic w.stew.ter.demonstr.ted that NFI/TiO_(2)not only achieves quasi-stoichiometr.c NH_(4)^(+)-to-N_(2)conver.ion,but also enhances H_(2)gener.tion efficiency w.th minimal competing r.actions such as r.duction of dissolved oxygen and r.active *** scaled-up w.C w.th NFI/TiO_(2)w.s demonstr.ted for.electr.lysis of toilet w.stew.ter.

关键词： w.stew.ter.electr.lysis cell Ir.doped NiFe_(2)O_(4) r.active chlor.ne species Decentr.lized H_(2)pr.duction On-site w.stew.ter.tr.atment

Coor.inated Cluster.Double Star.obser.ations of dayside flux tr.nsfer.events on 6 Apr.l 2004

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Science China(Technological Sciences) 2008年第10期51卷 1611-1619页

作者： Malcom w. DUNLOP Space Science and Technology Depar.ment Rutherford Appleton Laboratory Chilton Oxfordshire OX 11 0QX UK

w.th the Double Star.Pr.gr.m TC1 in the equator.al or.it and Cluster.tetr.hedr.n in the high latitude polar.or.it, a conjunct obser.ation of FTEs on the dayside magnetopause (MP) on Apr.l 6, 2004 is pr.sented in this study. The FTEs obser.ed by TC1 at low.latitudes ar. char.cter.zed to be gener.ted in the subsolar.r.gion and the obtained flux tube axes or.entate along the pr.dicted low.latitude component magnetic r.connection X-line, indicating that these FTEs w.r. mor. likely to be gener.ted thr.ugh multiple X-line r.connection or.single X-line bur.ty r.connec-tion. Dur.ng the same per.od, Cluster.also encounter.d a ser.es of magnetosheath FTEs w.th their.axes pointing r.ughly along the inter.lanetar. magnetic field. At last, the global FTE configur.tion is obtained fr.m obser.ations in differ.nt loca-tions, w.ich is in good agr.ement w.th the "elbow.shape" model.

关键词： magnetopause magnetic r.connection FTEs gener.tion mechanism global configur.tion

Effect of ter.ain and building str.ctur.s on the air.low.in an air.or.

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Jour.al of Zhejiang Univer.ity-Science A(Applied Physics & Engineer.ng) 2012年第6期13卷 461-468页

作者： Dennis Y. C. LEUNG w. Y. LO w. Y. CHOw.P. w. CHAN Depar.ment of Mechanical Engineer.ng The University of Hong Kong Hong Kong China Hong Kong Obser.ator. Hong Kong China

The aim of this study w.s to per.or. computational fluid dynamics (CFD) simulations on the air.low. at the Hong Kong Inter.ational Air.or. (HKIA). In par.icular. the effects of hangar.buildings and ter.ain w.r. studied to explor. the effects of tur.ulence on flying air.r.ft, especially dur.ng landing. The CFD simulation show.d that significant differ.nces in w.nd speeds may occur.betw.en the nor.h and the south r.nw.ys on the w.ster. par. of the HKIA under.typhoon conditions w.th a str.ng nor.h to nor.hw.ster.y w.nd. Simulation also show.d that the hanger.buildings betw.en the tw. r.nw.ys on the w.ster. side and the near.y ter.ain could be causing the obser.ed differ.nce in the w.nd speeds. The r.sults also indicated that these obstacles could cause significant w.nd speed var.ations at the w.ster. end of the south r.nw.y. This may affect the oper.tion of landing air.r.ft. The CFD r.sults for.a typical typhoon case w.r. analyzed and found to match the w.nd data r.cor.ed by an air.r.ft landing that day.

关键词： Computational fluid dynamics (CFD) Hong Kong Inter.ational Air.or. (HKIA) Low.level w.nd effect Hangar. Ter.ain

Using gr.und penetr.ting r.dar.to assess the var.ability of snow.w.ter.equivalent and melt in a mixed canopy for.st, Nor.her. Color.do

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Fr.ntier. of Ear.h Science 2017年第3期11卷 482-495页

作者： r.an w. w.BB Institute of Ar.tic and Alpine r.sear.h University of Colorado Boulder Boulder CO 80309-0450 USA

Snow.is an impor.ant envir.nmental var.able in headw.ter.systems that contr.ls hydr.logical pr.cesses such as str.amflow. gr.undw.ter.r.char.e, and evapotr.n- spir.tion. These pr.cesses w.ll be affected by both the amount of snow.available for.melt and the r.te at w.ich it melts. Snow.w.ter.equivalent （Sw.） and snow.elt ar. know. to var. w.thin complex subalpine ter.ain due to ter.ain and canopy influences. This study assesses this var.ability dur.ng the melt season using gr.und penetr.ting r.dar.to sur.ey multiple plots in nor.hw.ster. Color.do near.a snow.telemetr. （SNOTEL） station. The plots include south aspect and flat aspect slopes w.th open, conifer.us （subalpine fir. Abies lasiocar.a and engelman spr.ce, Picea engelmanii）, and deciduous （aspen, popu- lous tr.muooides） canopy cover. r.sults show.the high var.ability for.both Sw. and loss of Sw. dur.ng spr.ng snow.elt in 2014. The coefficient of var.ation for.Sw. tended to incr.ase w.th time dur.ng snow.elt w.er.as loss of Sw. r.mained similar. Cor.elation lengths for.Sw. w.r. betw.en tw. and five meter. w.th melt having cor.elation lengths betw.en tw. and four.meter.. The SNOTEL station r.gular.y measur.d higher.Sw. values r.lative to the sur.ey plots but w.s able to r.asonably captur. the over.ll mean loss of Sw. dur.ng melt. Gr.und Penetr.ting r.dar.methods can impr.ve futur. investiga- tions w.th the advantage of non-destr.ctive sampling and the ability to estimate depth, density, and Sw..

关键词： headw.ter. snow.elt snow.w.ter.equiva-lent gr.und penetr.ting r.ar SNOTEL

A differ.nt view. sensor. dr.ve in the polar.zed-light r.alm

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Cur.ent Zoology 2018年第4期64卷 513-523页

作者： Thomas w. Cr.NIN Depar.ment of Biological Sciences University of Maryland Baltimore MD 21250 USA

Sensor. dr.ve, the concept that sensor. systems pr.mar.ly evolve under.the influence of envir.nmen tal featur.s and that animal signals ar. evolutionar.ly shaped and tuned by these pr.viously existing sensor. systems, has been thor.ughly studied r.gar.ing visual signals acr.ss many animals. Much of this w.r. has focused on spectr.l aspects of vision and signals. Her., I r.view.w.r. on polar.zed light signals of animals and r.late these to w.at is know. of polar.zation visual systems, polar.zed light aspects of visual scenes, and polar.zationr.lated behavior.（e.g., or.entation, habitatfinding, contr.st enhancement）. Other.than the br.ad patter.s of scatter.d polar.zed light in the sky, most po lar.zation in both ter.estr.al and aquatic envir.nments r.sults fr.m either.r.flection or.scatter.ng in the hor.zontal plane. w.th over.ead illumination, hor.zontal featur.s such as the sur.aces of many leaves or.of air. w.ter.inter.aces r.flect hor.zontal polar.zation, and w.ter.scatter. hor.zontally polar.ized light under.most conditions. Sever.l animal species have been demonstr.ted to use hor.zontally polar.zed light fields or.featur.s in cr.tical aspects of their.biology. Significantly, most biological sig nals ar. also hor.zontally polar.zed. Her., I pr.sent r.levant polar.zationr.lated behavior.and discuss the hypothesis that sensor. dr.ve has evolutionar.ly influenced the str.ctur. of polar.zation signals. The paper.also consider. the evolutionar. or.gin of cir.ular.polar.zation vision and cir.ular.y polar.ized signals. It appear. that this class of signals did not evolve under.the influence of sensor. dr.ve. The study of signals based on polar.zed light is becoming a matur. field of r.sear.h.

关键词： animal communication polar.zed light sensor. dr.ve vision visual signal

Annual temper.tur.s dur.ng the last 2485 year. in the mid-easter. Tibetan Plateau infer.ed fr.m tr.e r.ngs

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Science China Ear.h Sciences 2009年第3期52卷 348-359页

作者： Hans w. LINDEr.OLM r.gional Climate Gr.up Department of Earth Sciences University of Gothenburg

By combining living tr.es and ar.haeological w.od, the annual mean temper.tur.s w.r. r.constr.cted based on r.ng-w.dth indices of the mid-easter. Tibetan Plateau for.the past 2485 year.. The climate var.ations r.vealed by the r.constr.ction indicate that ther. w.r. four.per.ods to have aver.ge tem- per.tur.s similar.to or.even higher.than that mean of 1970 to 2000 AD. A par.icular.y notable r.pid shift fr.m cold to w.r., w. call it the "Easter. Jin Event", occur.ed fr.m 348 AD to 413 AD. Calculation r.- sults show.that the temper.tur. var.ations over.the mid-easter. Tibetan Plateau ar. not only r.pr.- sentative for.lar.e par.s of nor.h-centr.l China, but also closely cor.espond to those of the entir. Nor.her. Hemispher. over.long time scales. Dur.ng the last 2485 year., the dow.fall of most major.dynasties in China coincides w.th inter.als of low.temper.tur.. Compar.d w.th the temper.tur. r.cor.s in other.r.gions of China dur.ng the last 1000 year., this r.constr.ction fr.m the Tibetan Plateau show. a significant w.r.ing tr.nd after.the 1950s.

关键词： mid-easter. Tibetan Plateau tr.e r.ngs temper.tur. var.ations dynasty’s dow.fall