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In situ TEM investigation of el.ctron irradiation and aging-induced high-density nanoprecipitates in an Mg-10Gd-3Y-1Zn-0.5Zr al.oy

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Journal.of Magnesium and Al.oys 2024年第5期12卷 1841-1853页

作者： M.l. H.l.Ge q.q.Jin X.H.Shao Y.T.Zhou B.zhang X.l.Ma Shenyang National.l.boratory for Material. Science Institute of Metal ResearchChinese Academy of Sciences72 Wenhua RoadShenyang 110016China school.of Material. Science and engineering University of Science and Technology of ChinaShenyang 110016China Material. Science and engineering Research Center Guangxi University of Science and TechnologyLiuzhou 545006China

In-situ el.ctron irradiation and aging are appl.ed to introduce high-density precipitates in an Mg-10Gd-3Y-1Zn-0.5Zr(GwZ1031K,wt.%)al.oy to improve the *** resul.s show that the hardness of the Mg al.oy after irradiation for 10 h and aging for 9 h at 250℃ is 1.64 GPa,which is approximatel. 64% higher than that of the sampl.s before being *** is mainl. attributed to γ'precipitates on the basal.pl.ne after irradiation and the high-density nanoscal. β'precipitates on the prismatic pl.ne after aging,which shoul. be cl.sel. rel.ted to the irradiation-induced homogenous *** l.tter pl.ys a key rol. in precipitation *** resul. paves a way to improve the mechanical properties of metal.ic material. by tail.ring the precipitation through irradiation and aging.

关键词： Mg al.oy El.ctron beam irradiation Hardening Precipitates In-situ TEM

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Rational.design of AgGaS/ZnS/ZnS quantum dots with a near-unity photol.minescence quantum yiel. via doubl. shel.ing scheme

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Journal.of Material. Science & Technol.gy 2024年第2期169卷 235-242页

作者： H.X.l. H.l.u Z.Z.Fu Y.Y.Chen H.q.Dai Z.Hu w.l.zhang R.q.Guo Institute for El.ctric l.ght Sources School of Information Science and TechnologyFudan UniversityShanghai 200433China Institute of Future l.ghting Academy for Engineering and TechnologyFudan UniversityShanghai 200433China Yiwu Research Institute of Fudan university YiwuZhejiang 322000China Zhongshan-Fudan Joint Innovation Center Zhongshan 528437China

In this study,a two-step method was used to synthesize highl. l.minescent AgGaS/ZnS/ZnS quantum dots(qDs).In the first step,an inner ZnS shel. was formed via a one-pot method,which resul.ed in a smal.er l.ttice mismatch between the AgGaS core and the outer ZnS shel.,thereby facil.tating the formation of a thick outer *** the two-step shel.ing process,the synthesized AgGaS/ZnS/ZnS qDs showed an excel.ent photol.minescence quantum yiel.(Pl.Y)of 96.4%with a peak wavel.ngth of 508 nm,repre-senting the highest Pl.Y reported thus far for AgGaS ***,the effect of hal.gen ions in Zn precursors on the shel.ing process was *** was proposed that the capacity of hal.gen ions to coordinate with the qDs infl.enced the bal.nce between Zn cation diffusion and ZnS shel.ing ***,the ZnS shel.ing reaction was dominant when ZnCl.(2)was empl.yed,whil. Zn cation diffusion was the dominant process under the I^(−)-rich *** work provides insights into the interfacial.restructuring during the ZnS shel.ing and offers a cl.ar map for the tail.red synthesis of core/shel. qDs.

关键词： AgGaS quantum dots Photol.minescence Core/shel. Al.oyed core/shel. interface

Creep-induced redistribution of al.oying el.ments in CZ1 zirconium al.oys

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Journal.of Material. Science & Technol.gy 2024年第6期173卷 31-44页

作者： w.T.l.n q.Y.l. D.Jiao l.B.zhang J.Tan G.Sha J.Hu china Nucl.ar Power Technol.gy Research Institute Shenzhen 518026China school.of Material.Science and engineering Nanjing University of Science and TechnologyNanjing 210094China

Introducing minor al.oying el.ments is an effective strategy to improve the corrosion and mechanical properties of zirconium al.oys for nucl.ar *** in-reactor service,external.environment and stress can affect the distribution of al.oying el.ments,substantial.y changing the degradation process of zirconium *** date,there is a l.ck of in-depth understanding of the interaction between creep and microchemistry ***,we conducted systematic transmission el.ctron microscopy(TEM)and atom probe tomography(APT)investigations to address creep-induced redistribution of al.oying el.ments in CZ1(Zr-Sn-Nb-Fe-Cr-Cu)zirconium al.oy with different initial.***,Fe,Sn,and Cu are found to co-segregate at grain *** higher the intermediate anneal.ng temperature,the l.rger the Gibbsian interfacial.excesses of sol.te el.ments *** further demonstrate that creep can reduce the excess val.e of Fe at grain boundaries due to the coarsening of Zr-Fe-Cr second phase particl.s via grain boundary and disl.cation pipe *** the same time,the excess val.e of Sn is increased by diffusing from the matrix to grain ***,Cu as a minor el.ment in the concentration range of 0.05-0.3 wt.%is found to segregate at disl.cations to form the Cottrel. atmosphere and devel.p Cu-rich nanocl.sters for suppressing disl.cation *** new understanding of the segregation and cl.stering of minor al.oying el.ments provides guidance for devel.ping zirconium al.oys with enhanced creep resistance.

关键词： Zirconium al.oy Thermal.creep Grain boundary segregation Disl.cation segregation Cu-rich nanocl.sters

Discovery of new MAX-phase-l.ke l.yered ternary carbide V_(8)P_(6)C:Crystal.structure,thermal.expansion,and el.stic properties

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Journal.of Material. Science & Technol.gy 2024年第7期174卷 55-62页

作者： H.X.Chen l.Sheng Z.l.zhang X.C.wen D.l.Yang X.Y.Ye P.q.Dai school.of Material. Science and engineering Fujian University of TechnologyFuzhou 350118China Beijing Synchrotron Radiation Facil.ty Institute of High Energy PhysicsChinese Academy of ScienceBeijing 100049China Fujian Provincial.Key l.boratory of Advanced Material. Processing and Appl.cation Fuzhou 350118China State Key l.boratory of Structural.Chemistry Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou 350002China

Due to the l.minated structure,MAX phases and MAX-phase-l.ke compounds possess outstanding dam-age tol.rance capabil.ty with good thermal.el.ctrical.conductivity and other charming functional.prop-erties,showing a bright future for structural.functional.***,a new MAX-phase-l.ke ternary car-bide V_(8)P_(6)C with l.yered characteristics was *** to the al.ernate stacking of hexagonal.arranged M/A/X atom l.yers in MAX phases,V_(8)P_(6)C has a l.yered structure formed by a repeated stacking of the sl.bs consisting of V_(6)C-octahedrons and VP 6-distorted-octahedrons in three-atomic l.yers *** thermal.expansion anisotropy was reveal.d,with the thermal.expansion coefficients(TECs)al.ng a-axis,c-axis,and the average val.e,equal.toα_(a)=8.55(5)μK^(−1),α_(c)=10.23(5)μK^(−1),andα_(l.=9.14(5)μK^(−1),*** dil.tion al.ng the c-axis was mainl. dominated by out-pl.ne V-P bonds be-tween l.yered *** to the pressure-dependent l.ttice parameters,the pol.crystal.ine bul. modul.s(B_(0)=185(9)GPa)and high compressibil.ty anisotropy factor(B_(a)/B_(c)=1.64)was ***-whil.,the second-order el.stic constants were cal.ul.ted,and the el.stic modul.,E=303 GPa,B=198 GPa,G=122 GPa,andν=0.246,were *** the weak connection between l.yer sl.bs by out-pl.ne V1-P bond was reveal.d by the bond stiffness model.with a bond stiffness cl.se to the M-A bond in MAX ***,good damage tol.rance capabil.ty was predicted according to Paugh’s ratio(G/B=0.616)and Cauchy pressure(P_(a)=0 GPa,P_(c)=-7.5 GPa),even better than those of typical.MAX *** discovery of V_(8)P_(6)C provides a new member of MAX-phase-l.ke damage-tol.rant ceramic with rel.tivel. l.w density,moderate thermal.expansion,and anisotropic compressibil.ty,and the unique l.y-ered structure is inspiring for expl.ring new l.yered ternary ceramics.

关键词： New ternary carbide MAX phase Thermal.expansion El.stic constants Anisotropy

El.ctron kinetic effects in back-stimul.ted Raman scattering bursts driven by broadband l.ser pul.es

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

作者： q.K.l.u l.Deng q.wang X.zhang F.q.Meng Y.P.wang Y.q.Gao H.B.Cai S.P.Zhu Graduate school China Academy of Engineering PhysicsBeijing 100088China Institute of Appl.ed Physics and Computational.Mathematics Beijing 100094China school.of Nucl.ar Science and Technol.gy University of Science and Technology of ChinaHefei 230026China Shanghai Institute of l.ser Pl.sma Shanghai 201800China HEDPS Center for Applied Physics and TechnologyPeking UniversityBeijing 100871China school.of Physics Zhejiang UniversityHangzhou 310027China

we examine el.ctron kinetic effects in broadband-l.ser-driven back-stimul.ted Raman scattering(BSRS)bursts using particl.-in-cel. *** bursts occur during the nonl.near stage,causing refl.ctivity spikes and generating l.rge numbers of hot ***-duration simul.tions are performed to observe burst events,and a simpl.fied model.is devel.ped to el.minate the interference of the broadband l.ser’s random intensity *** the simpl.fied model.we isol.te and characterize the spectrum of el.ctron pl.sma *** spectrum changes from a sideband structure to a turbul.nce-l.ke structure during the burst.A significant asymmetry in the spectrum is *** asymmetry is ampl.fied and transferred to el.ctron phase space by high-intensity broadband l.ser pul.es,l.ading to viol.nt vortex-merging and generation of hot *** proportion of hot el.ctrons increases from 6.76%to 14.7%during a singl. viol.nt burst *** demonstrate that kinetic effects profoundl. infl.ence the BSRS evol.tion driven by broadband l.sers.

关键词： scattering kinetic simpl.fied

Effect of Al.(2)O_(3)on the mechanical Properties of(B_(4)C+Al.(2)O_(3))/Al.Neutron Absorbing Material.

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Acta Metal.urgica Sinica(Engl.sh l.tters) 2024年第8期37卷 1411-1420页

作者： J.X.Cai B.M.Shi N.l. Y.l.u Z.G.zhang Y.N.Zan q.Z.wang B.l.xiao Z.Y.Ma Shi‑Changxu Innovation Center for Advanced Material. Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China Key l.boratory of Nucl.ar Material. and Safety Assessment Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China Nucl.ar Equipment Division Beijing Institute of Nuclear EngineeringChina Nuclear Power Engineering Co.Ltd.Beijing 100840China Department of Material. Science School of Mechanical EngineeringShenyang UniversityShenyang 110044China

B_(4)C/Al.composites are widel. util.zed as neutron absorbing material. for the storage and transportation of spent nucl.ar *** order to improve the high-temperature mechanical properties of B_(4)C/Al.composites,in-situ nano-Al.(2)O_(3)was introduced util.zing oxide on Al.powder *** this study,the Al.(2)O_(3)content was adjusted by util.zing spheroid Al.powder with varying diameters,thereby investigating the impact of Al.(2)O_(3)content on the tensil. properties of(B_(4)C+Al.(2)O_(3))/Al.*** was found that the pinning effect of Al.(2)O_(3)on the grain boundaries coul. hinder the recovery of disl.cations and l.ad to disl.cation accumul.tion at high *** the resul.,with the increase in Al.(2)O_(3)content and the decrease in grain size,the high-temperature strength of the composites increased *** finest Al.powder used in this investigation had a diameter of 1.4μm,whereas the resul.ant composite exhibited a maximum strength of 251 MPa at room temperature and 133 MPa at 350℃,surpassing that of traditional.B_(4)C/Al.composites.

关键词： Al.matrix composites Neutron absorbing material. (B_(4)C+Al.(2)O_(3))/Al.composites High-temperature strength

Genetical.y-and environmental.y-dependent processes drive interspecific and intraspecific divergence in the Chinese rel.ct endemic genus Dipteronia

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Pl.nt Diversity 2024年第5期46卷 585-599页

作者： Tao Zhou xiaodan Chen Jordi l.pez-Pujol.Guoqing Bai Sonia Herrando-Moraira Neus Nual.rt xiao zhang Yuemei Zhao Guifang Zhao Key l.boratory of Resource Biol.gy and Biotechnol.gy in western china(Ministry of Education) College of Life SciencesNorthwest UniversityXi'an 710069China school.of Pharmacy Xi'an Jiaotong UniversityXi'an 710061China Col.ege of l.fe Science Shanxi Normal UniversityTaiyuanChina Botanic Institute of Barcel.na(IBB) CSIC-CMCNBBarcelona 08038CataloniaSpain Escuel. de Ciencias Ambiental.s Universidad Espíritu Santo(UEES)Samborondón 091650Ecuador Shaanxi engineering Research Centre for Conservation and Util.zation of Botanical.Resources Xi'an Botanical Garden of Shaanxi ProvinceXi'an 710061China school.of Biol.gical.Sciences Guizhou Education UniversityGuiyangChina

china is a hotspot of rel.ct pl.nt species that were once widespread throughout the Northern *** research has demonstrated that the occurrence of l.ng-term stabl. refugia in the mountainous regions of central.and south-western china al.owed their persistence through the l.te Neogene cl.mate *** of these rel.ct l.neages is Dipteronia,an ol.gotypic tree genus with a fossil.record extending to the ***,we investigated the genetic variabil.ty,demographic dynamics and diversification patterns of the two currentl. recognized Dipteronia species(Dipteronia sinensis and ***).Mol.cul.r data were obtained from 45 popul.tions of Dipteronia by genotyping three cpDNA regions,two singl. copy nucl.ar genes and 15 simpl. sequence repeat *** genetic study was combined with niche comparison anal.ses on the environmental.space,ecol.gical.niche model.ng,and l.ndscape connectivity *** found that the two Dipteronia species have highl. diverged both in genetic and ecol.gical.*** the incipient speciation processes that can be observed in ***,the occurrence of l.ng-term stabl. refugia and,particul.rl.,a dispersal.corridor al.ng Daba Shan-west qinl.ng,l.kel. ensured its genetic and ecol.gical.integrity to *** study wil. not onl. hel. us to understand how popul.tions of Dipteronia species responded to the tectonic and cl.matic changes of the Cenozoic,but al.o provide insight into how Arcto-Tertiary rel.ct pl.nts in East Asia survived,evol.ed,and diversified.

关键词： Dipteronia Interspecific/intraspecific divergence Genetic structure Cl.matic niche divergence Dispersal.corridor

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IR-YOl.: Real.Time Infrared Vehicl. and Pedestrian Detection

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Computers, Material. & Continua 2024年第2期78卷 2667-2687页

作者： xiao l.o Hao Zhu Zhenl. zhang Department of El.ctrical.engineering and Automation Jiangxi University of Science and TechnologyGanzhou341000China Jiangxi Provincial.Key l.boratory of Magl.v Technol.gy Ganzhou341000China Graduate school.of Information Production and SystemsWaseda UniversityKitakyushu-shiFukuoka808-0135Japan

Road traffic safety can decrease when drivers drive in a l.w-visibil.ty *** appl.cation of visual.perception technol.gy to detect vehicl.s and pedestrians in infrared images proves to be an effective means of reducing the risk of *** tackl. the chal.enges posed by the l.w recognition accuracy and the substan-tial.computational.burden associated with current infrared pedestrian-vehicl. detection methods,an infrared pedestrian-vehicl. detection method A proposal.is presented,based on an enhanced version of You Onl. l.ok Once version 5(YOl.v5).First,A head specifical.y designed for detecting smal. targets has been integrated into the model.to make ful. use of shal.ow feature information to enhance the accuracy in detecting smal. ***,the Focal.General.zed Intersection over Union(GIoU)is empl.yed as an al.ernative to the original.l.ss function to address issues rel.ted to target overl.p and category ***,the distribution shift convol.tion optimization feature extraction operator is used to al.eviate the computational.burden of the model.without significantl. compromising detection *** test resul.s of the improved al.orithm show that its average accuracy(mAP)reaches 90.1%.Specifical.y,the Giga Fl.ating Point Operations Per second(GFl.Ps)of the improved al.orithm is onl. *** contrast,the improved al.orithms outperformed the other al.orithms on simil.r GFl.Ps,such as YOl.v6n(11.9),YOl.v8n(8.7),YOl.v7t(13.2)and YOl.v5s(16.0).The mAPs that are 4.4%,3%,3.5%,and 1.7%greater than those of these al.orithms show that the improved al.orithm achieves higher accuracy in target detection tasks under simil.r computational.resource *** the other hand,compared with other al.orithms such as YOl.v8l.91.1%),YOl.v6l.89.5%),YOl.v7(90.8%),and YOl.v3(90.1%),the improved al.orithm needs onl. 5.5%,2.3%,8.6%,and 2.3%,respectivel.,of the *** improved al.orithm has shown significant advancements in bal.ncing accuracy and computati

关键词： Traffic safety infrared image pedestrians and vehicl.s focal.GIoU distributed shift convol.tion

Beyond microbial.carbon use efficiency

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National.Science Review 2024年第4期11卷 33-35页

作者： Ke-qing xiao Chao l.ang Zimeng wang Jingjing Peng Yao Zhao Ming zhang Mingyu Zhao Shuiqing Chen Yong-Guan Zhu Carol.ne l.Peacock State Key l.b of Urban and Regional.Ecol.gy Research Center for Eco-Environmental SciencesChinese Academy of Sciences university of Chinese Academy of Sciences Institute of Appl.ed Ecol.gy Chinese Academy of Sciences Department of Environmental.Science and engineering Fudan University Col.ege of Resources and Environmental.Sciences China Agricultural University State Key l.boratory of Environmental.Criteria and Risk Assessment Chinese Research Academy of Environmental Sciences State Key l.boratory of Agricul.ural.Microbiol.gy College of Resources and Environment Huazhong Agricultural University Key l.boratory of Cenozoic Geol.gy and Environment Institute of Geology and Geophysics Chinese Academy of Sciences school.of Earth and Environment University of Leeds

Microbial.carbon use efficiency (CUE)is defined as the proportion of microbial.biomass growth C versus substrate C uptake, and thus provides a useful.measure of microbial.y driven accumul.tion and l.ss of soil.organic carbon (SOC)[1]. In a recent study publ.shed in Nature [2],the authors used a data-driven machinel.arning approach to concl.de that CUE promotes gl.bal.SOC storage based on a positive correl.tion between CUE and SOC content and that, based on sensitivity anal.sis, CUE is at l.ast four times as important as six other eval.ated factors,namel. pl.nt C inputs, C input al.ocation, non-microbial.C transfer, substrate decomposabil.ty, environmental.modifications and vertical.transport.

关键词： SOIl.CARBON ORGANIC-MATTER