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Journal of Magnesium and Alloys 2024年第5期12卷 1841-1853页

作者： M.Lv H.L.Ge Q.Q.Jin X.H.Shao y.t.zhou B.Zhang X.L.Ma Shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of Sciences72 Wenhua RoadShenyang 110016China School of Materials Science and Engineering University of Science and Technology of ChinaShenyang 110016China Materials Science and Engineering Research Center Guangxi University of Science and TechnologyLiuzhou 545006China

In-situ electron irradiation and aging are applied to introduce high-density precipitates in an Mg-10Gd-3y-1Zn-0.5Zr(GWZ1031K,wt.%)alloy to improve the *** results show that the hardness of the Mg alloy after irradiation for 10 h and aging for 9 h at 250℃ is 1.64 GPa,which is approximately 64% higher than that of the samples before being *** is mainly attributed to γ'precipitates on the basal plane after irradiation and the high-density nanoscale β'precipitates on the prismatic plane after aging,which should be closely related to the irradiation-induced homogenous *** latter plays a key role in precipitation *** result paves a way to improve the mechanical properties of metallic materials by tailoring the precipitation through irradiation and aging.

关键词： Mg alloy Electron beam irradiation Hardening Precipitates In-situ tEM

Structure evolution of the Fe_(3)C/Fe interface mediated by cementite decomposition in cold-deformed pearlitic steel wires

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Journal of Materials Science & technology 2022年第6期101卷 28-36页

作者： y.t.zhou X.H.Shao S.J.Zheng X.L.Ma Shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China tianjin Key Laboratory of Materials Laminating Fabrication and Interface Control technology School of Materials Science and EngineeringHebei University of TechnologyTianjin 300130China

Cold-drawn pearlitic steel wire is irreplaceably used in industry owing to its outstanding mechanical property which is dominated by the cementite/ferrite(Fe_(3)C/Fe) interfaces in the material. However, the fine structures of the Fe3C/Fe interfaces in the deformed wires are less known to date. In this work, transmission electron microscopic investigation was performed on the atomic structures of the interfaces with the Isaichev orientation relationship(OR) in the wires with progressive deformation strains. In addition to the effect of the dislocation/interface interactions, this work revealed that the deformation-induced partial decomposition of cementite plays an important role in the interface reconstruction during deformation. the interfacial carbon vacancies generated by cementite decomposition and particularly, the amorphization of cementite layers in the sample with ε > 1 could effectively annihilated the interfacial dislocations and consequently relaxed the interfacial stress. the correlations between the interface structure changes and the mechanical properties of the wires were discussed.

关键词： Pearlitic steel Cementite decomposition Interface structure Deformation transmission electron microscopy

Formation of β' phase in LPSO structures in an Mg88Co5y7 alloy

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Journal of Magnesium and Alloys 2022年第1期10卷 175-182页

作者： Q.Q.Jin X.H.Shao y.t.zhou B.Zhang S.J.Zheng X.L.Ma Shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of Sciences72 Wenhua Road110016 ShenyangChina Materials Science and Engineering Research Center Guangxi University of Science and TechnologyLiuzhou 545006China School of Materials Science and Engineering Research Institute for Energy Equipment MaterialsHebei University of TechnologyTianjin 300130China

Formation of β’ phase in long-period stacking ordered(LPSO) structures in an Mg;Co;y;(at.%) alloy after aging at 200 °C for 24 h or electron beam(EB) irradiation has been studied by high-angle annular dark-field scanning transmission electron microscopy(HAADFStEM). β’ phase was precipitated only in the Mg matrix but not in LPSO structures after aging at 200 °C for 24 h. LPSO structure containing stacking defects transforms into the β’-long phase during EB irradiation, which plays a key role in accelerating solute atoms’ diffusion. New complex β’(LPSO) structures formed in the alloy after EB irradiation, such as β’(12 H) structure with an orthorhombic lattice(Mg;y, Cmcm,a = 2 _(a0)= 0.642 nm, b=4√3_(a0), c = 6 _(c0)= 3.12 nm).

关键词： Magnesium alloys Long-period stacking ordered(LPSO)structure HAADF-StEM β’phase

Phase field modeling of ferroelastic variant switching in yttria-stabilized t'zirconia with strain gradient elasticity and interface tension

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Science China(technological Sciences) 2024年第5期67卷 1443-1457页

作者： zhou QianQian WEI yueGuang zhou yiChun yANG Li College of Engineering BIC-ESATPeking UniversityBeijing100871China School of Advanced Materials and Nanotechnology Xidian UniversityXi’an710126China Frontier Research Center of thin Films and Coatings for Device Applications Academy of Advanced Interdisciplinary ResearchXidian UniversityXi’an710126China

the 6–8 wt%yttria-stabilized zirconia with a tetragonal structure(t’-ySZ)is extensively employed in thermal barrier *** exceptional fracture toughness of t’-ySZ can be attributed to its distinctive ferroelastic toughening *** and interface tension play a critical role in ferroelastic variant switching at the micro-and *** paper presents an original thermodynamically consistent phase field(PF)theory for analyzing ferroelastic variant switching at the micro-and nano-scale of t’-*** theory incorporates strain gradient elasticity using higher-order elastic energy and interface tension tensor via geometric nonlinearity to represent biaxial tension resulting from interface ***,a mixed-type formulation is employed to implement the higher-order theory through the finite element *** an interface in equilibrium,the effects of strain gradient elasticity result in a more uniform distribution of stresses,whereas the presence of interface tension tensor significantly amplifies the stress magnitude at the *** introduction of an interface tension tensor increases the maximum value of stress at the interface by a factor of 4 to *** nucleation and evolution of variants at a pre-existing crack tip in a mono-phase t’-ySZ have also been *** strain gradient elasticity is capable of capturing the size effect of ferroelastic variant switching associated with microstructures in ***,when the grain size approaches that of the specimen,the critical load required for variant switching at the crack tip increases,resulting in greater dissipation of elastic energy during ferroelastic variant ***,the interface tension accelerates the evolution of *** presented framework exhibits significant potential in modeling ferroelastic variant switching at the micro-and nano-scale.

关键词： thermodynamics strain gradient elasticity interface tension phase field method ferroelastic variant switching

track-before-detect for bistatic radar based on pseudo-spectrum

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Chinese Journal of Aeronautics 2024年第1期37卷 236-246页

作者： tao HAN Gongjian zhou School of Electronics and Information Engineering Harbin Institute of TechnologyHarbin 150001China Key Laboratory of Marine Environmental Monitoring and Information Processing Ministry of Industry and Information TechnologyHarbin 150001China

track-Before-Detect(tBD) is an efficient method to detect dim targets for radars. Conventional tBD usually follows an approximate motion model of the target, which may cause an inaccurate integration of the target energy. A tBD technique on basis of pseudo-spectrum in mixed coordinates adopting an accurate motion model for bistatic radar system is developed in this *** predicted position in bistatic polar plane is derived according to a nonlinear function that exactly describes the constant Cartesian velocity motion. then around the predicted position, a pseudo-spectrum is formulated and its samples are accumulated to the integration frame for energy integration. the evolution of the state and the procedure of accumulation of the target energy are derived elaborately. the superior performance of the proposed method is demonstrated by some simulations.

关键词： Weak target detection Bistatic radar track-before-detect Pseudo-spectrum Multiframe integration

High association strengths are linked to phenotypic similarity,including plumage color and patterns,of participants in mixed-species bird flocks of southwestern China

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Current Zoology 2024年第1期70卷 34-44页

作者： Liping zhou Christos Mammides youfang Chen Wenyi zhou Wenzhang Dai Edward L.Braun Rebecca t.Kimball yang Liu Scott K.Robinson Eben Goodale Guangxi Key Laboratory of Forest Ecology and Conservation College of ForestryGuangxi UniversityNanning 530004China Kunming Natural History Museum of Zoology Kunming Institute of ZoologyChinese Academy of SciencesKunming 650223China Nature Conservation Unit Frederick University7Yianni Frederickou StreetPallouriotissaNicosia 1036Cyprus State Key Laboratory of Vegetation and Environmental Change Institute of BotanyChinese Academy of SciencesBeijing 100093China Florida Museum of Natural History University of FloridaGainesvilleFL 34201USA Department of Biology University of FloridaGainesvilleFL 34201USA School of Life Science and Institute of Wetland Ecology Nanjing UniversityNanjing 210000China State Key Laboratory of Biocontrol School of EcologySun-Yatsen UniversityGuangzhou 510275China Department of Health and Environmental Science Xi'an Jiaotong Liverpool UniversitySuzhou 215123China

Participants in mixed-species bird flocks(MSFs)have been shown to associate with species that are similar in body size,diet,and evolutionary history,suggesting that facilitation structures these *** addition,several studies have suggested that species in MsFs resemble each other in their plumage,but this question has not been systematically investigated for any MsF *** the nonbreeding season of 2020 and 2021,we sampled 585 MSFs on 14 transects in 2 habitats of tongbiguang Nature Reserve in western yunnan Province,*** performed social network analysis and the Multiple Regression Quadratic Assignment Procedure to evaluate the effect of 4 species traits(body size,overall plumage color,distinctive plumage patterns,and diet)and evolutionary history on species association strength at the whole-MSF and within-MSF *** 41 significant relationships showed that species with stronger associations were more similar in their various *** size had the strongest effect on association strength,followed by phylogeny,plumage patterns,and plumage color;diet had the weakest *** results are consistent with the hypotheses that the benefits of associating with phenotypically similar species outweigh the potential costs of interspecific competition,and that trait matching can occur in plumage characteristics,albeit more weakly than in other *** explanations exist as to why similarities in plumage may occur in MSFs,including that they could reduce predators'ability to target phenotypically"odd"*** trait matching in plumage occurs through assortative processes in ecological time or is influenced by co-evolution requires furtherstudy.

关键词： co-evolution interaction networks mixed-species animal groups phenotypic similarity trait convergence

Efficient guiding and focusing of intense laser pulse using periodic thin 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.Huang K.Jiang C.N.Wu H.Peng P.C.hen R.Li H.B.Zhuo C.t.zhou Shenzhen Key Laboratory of Ultraintense Laser and Advanced Material technology Center for Intense Laser ApplicationTechnologyand College of Engineering PhysicsShenzhen Technology UniversityShenzhen 518118People’s Republic of China

Slits have been widely used in laser-plasma interactions as plasma optical components for generating high-harmonic light and controlling laser-driven particle ***,we propose and demonstrate that periodic thin slits can be regarded as a new breed of optical elements for efficient focusing and guiding of intense laser *** fundamental physics of intense laser interaction with thin slits is studied,and it is revealed that relativistic effects can lead to enhanced laser focusing far beyond the pure diffractive focusing *** addition,the interaction of an intense laser pulse with periodic thin slits makes it feasible to achieve multifold enhancement in both laser intensity and energy transfer efficiency compared with conventional *** results provide a novel method for manipulating ultra-intense laser pulses and should be of interest for many laser-based applications.

关键词： laser pulse intense

Stabilization/solidification mechanisms of tin tailings and fuming slag-based geopolymers for different heavy metals

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Frontiers of Environmental Science & Engineering 2024年第5期18卷 43-55页

作者： Xian zhou Zhengfu Zhang Hui yang School of Materials Science and Engineering Kunming University of Science and TechnologyKunming650093China Kunming Metallurgical Research Institute Co. Ltd.Kunming650031China

tin mine tailings(tMt)and fuming slag(FS)contain many heavy metals(As,Cr,Cu,Zn and Mn)that cause severe pollution to the ***,geopolymers were prepared using tMt,FS and flue gas desulfurization gypsum(FGDG)to immobilize heavy metals,and their compressive strength and heavy metal leaching toxicity were *** was first determined that t4F5(tMt:FS=4:5)sample exhibited the highest compressive strength(7.83 MPa).t4F5 achieved 95%immobilization efficiency for As and Cr,and nearly 100%for Cu,Zn and Mn,showing good immobilization performance.A series of characterization analyses showed that heavy metal cations can balance the charge in the geopolymer and replace Al in the geopolymer structure to form covalent *** addition,about 2%–20%of heavy metal Fe was immobilized in hydration products,heavy metal hydroxides and non-bridging Si–O and Al–O coordination with silica-aluminate ***_(3)^(3−) was oxidized into AsO_(4)^(3−),which may form Ca–As or Fe–As ***_(2)O_(7)^(2−)was converted to CrO_(4)^(2−)under alkaline environment and then combined with OH−to form Cr(OH)3 ***^(2+)may react directly with dissolved silicate to form Mn_(2)SiO_(4) and also form Mn(OH)_(2) *** unstable Mn(OH)_(2) can be further oxidized to MnO_(2).the heavy metal cations were immobilized in the silicoaluminate lattice,while the anions tended to form insoluble *** results may benefit the industry and government for better handling of tMt,FS and solid wastes containing the abovementioned five heavy metals.

关键词： Heavy metals Cementitious materials tin tailings Stabilization/solidification Redox

Cybersecurity Landscape on Remote State Estimation:A Comprehensive Review

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IEEE/CAA Journal of Automatica Sinica 2024年第4期11卷 851-865页

作者： Jing zhou Jun Shang tongwen Chen the Department of Electrical and Computer Engineering University of AlbertaEdmonton AB T6G 1H9Canada the Department of Control Science and Engineering and Shanghai Research Institute for Intelligent Autonomous Systems Tongji UniversityShanghai 200092China

Cyber-physical systems(CPSs)have emerged as an essential area of research in the last decade,providing a new paradigm for the integration of computational and physical units in modern control *** state estimation(RSE)is an indispensable functional module of ***,it has been demonstrated that malicious agents can manipulate data packets transmitted through unreliable channels of RSE,leading to severe estimation performance *** paper aims to present an overview of recent advances in cyber-attacks and defensive countermeasures,with a specific focus on integrity attacks against ***,two representative frameworks for the synthesis of optimal deception attacks with various performance metrics and stealthiness constraints are discussed,which provide a deeper insight into the vulnerabilities of ***,a detailed review of typical attack detection and resilient estimation algorithms is included,illustrating the latest defensive measures safeguarding RSE from ***,some prevalent attacks impairing the confidentiality and data availability of RSE are examined from both attackers'and defenders'***,several challenges and open problems are presented to inspire further exploration and future research in this field.

关键词： Cyber-attacks Kalman filtering remote state estimation unreliable transmission channels

Prediction of damage potential in mainshock–aftershock sequences using machine learning algorithms

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Earthquake Engineering and Engineering Vibration 2024年第4期23卷 919-938页

作者： zhou zhou Wang Meng Han Miao yu Xiaohui Lu Dagang School of Civil and transportation Engineering Beijing University of Civil Engineering and ArchitectureBeijing 100044China Multi-Functional Shaking tables Laboratory Beijing University of Civil Engineering and ArchitectureBeijing 100044China College of Civil Engineering Tongji UniversityShanghai 200092China College of Civil Engineering and Architecture Guilin University of TechnologyGuilin 541004China School of Civil Engineering Harbin Institute of TechnologyHarbin 150090China

Assessing the potential damage caused by earthquakes is crucial for a community’s emergency *** this study,four machine learning(ML)methods—random forest,extremely randomized trees,AdaBoost(AB),and gradient boosting(GB)—were employed to develop prediction models for the damage potential of the mainshock(DIMS)and mainshock–aftershock sequences(DIMA).Building structures were modeled using eight single-degree-of-freedom(SDOF)systems with different hysteretic rules.A set of 662 recorded mainshock–aftershock(MS-AS)ground motions was selected from the PEER *** intensity measures(IMs)were chosen to represent the characteristics of the mainshock and *** results revealed that the selected ML methods can well predict the structural damage potential of the SDOF systems,except for the AB *** GB model exhibited the best performance,making it the recommended choice for predicting DIMS and DIMA among the four ML ***,the impact of input variables in the prediction was investigated using the shapley additive explanations(SHAP)*** high-correlation variables were sensitive to the structural period(t).At t=1.0 s,the mainshock peak ground velocity(PGVM)and aftershock peak ground displacement(PGDA)significantly influenced the prediction of *** t increased to 5.0 s,the primary high-correlation factor of the mainshock IMs changed from PGVM to the mainshock peak ground displacement(PGDM);however,the highcorrelation variable of the aftershock IMs remained *** high-correlation factors for DIMS showed trends similar to those of ***,a table summarizing the first and second high-correlation variables for predicting DIMS and DIMA were provided,offering a valuable reference for parameter selection in seismic damage prediction for mainshock–aftershock sequences.

关键词： machine learning mainshock-aftershock damage potential prediction the high-correlation variables SDOF systems