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Acta Metallurgica Sinica(English Letters) 2017年第5期30卷 464-469页

作者： Kai Yang Jin-Shan Zhang xi-mei zong Wei Liu Chun-xiang Xu College of Materials Science and Engineering TaiyuanUniversity of Technology Taiyuan 030024 China Shanxi Key Laboratory of Advanced Magnesium-based Materials Taiyuan 030024China

The spheroidizing mechanism of W-phase in the Mg–Zn–Y–Mn–（B） alloys during solid-solution treatment was investigated by using kinetic methodologies. The microstructure and mechanical properties of heat-treated Mg_（94）Zn_（2.5）-Y_（2.5）Mn_1 alloy containing 0.003 wt% B were compared with heat-treated Mg_（94）Zn_（2.5）-Y_（2.5）Mn_1 alloy. The heat-treated Mg_（94）Zn_（2.5）-Y_（2.5）Mn_1 alloy with 0.003 wt% B contained fine and uniform W-phase particles, which exhibited optimal mechanical performance. The ultimate tensile strength, yield strength and elongation were 287.7, 125.5 MPa and 21.1%,respectively.

关键词： Magnesium alloys W-phase Spheroidizing Kinetics Microstructure Mechanical properties

Effect of Precipitated Phases on Corrosion of Mg95.8Gd3Zn1Zr0.2 Alloy with Long-Period Stacking Ordered Structure

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Acta Metallurgica Sinica(English Letters) 2016年第1期29卷 32-38页

作者： xi-mei zong Dan Wang Wei Liu Kai-Bo Nie Chun-xiang Xu Jin-Shan Zhang College of Materials Science and Engineering Taiyuan University of Technology Taiyuan 030024 China Shanxi Key Laboratory of Advanced Magnesium-Based Materials Taiyuan 030024 China Department of Chemistry Taiyuan Normal UniversityTaiyuan 030031 China

The microstructure of the precipitated phases of ***3Zn1Zro.2 alloys with long-period stacking ordered structure before and after heat treatment is discussed. The corrosion properties of the as-cast （F）, solid-solution （T4） and aging-treated （T6） alloys in 1% NaC1 solution are studied. The hydrogen evolution and electrochemical measurements display that the as-cast ***3Zn1Zro.2 alloy with the continuous network eutectic phase exhibits the greatest corrosion resistance, while T6 sample with some needle-like phases and the particle phases is the worst among the three alloys. It is proposed to be mainly related to the amount, composition, microstructure and distribution of the precipitated phases.

关键词： Mg-Gd-Zn Corrosion properties Long-period stacking ordered (LPSO) Microstructure

Modular assembly of complex C-alkyl glycoside enabled via cooperative NHC and photoredox catalysis

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Science China Chemistry 2025年

作者： Rui-Qiang Jiao Ming Li xi Chen mei-Ze Xu Tian Ding xiao-Ping Gong Zhuo-mei Li Xue-Yuan Liu Yong-Min Liang State Key Laboratory of Applied Organic Chemistry Lanzhou University College of Chemistry and Chemical Engineering Northwest Normal University

C-Alkyl glycosides are found in natural products and are indispensable in drug development programs,owing to their diverse range of medicinal ***-component reactions involving glycosyl radical addition are well documented and proved efficient for the C-alkyl glycosides ***,multicomponent reactions for the rapid and controllable construction of structurally diversified C-alkyl glycosides in a single step remains a significant challenge due to the issues associated with balancing reactivity,compatibility,and ***,we report an NHC and photoredox co-catalyzed three-component method to access complex and valuable C-alkyl *** protocol exhibits broad substrate scope and excellent chemoand ***,nine types of sugars are compatible with this *** addition,the generality of this catalytic strategy was further highlighted by the potential for scalable production,the feasibility of further modifications of the products and its successful application in the late-stage functionalization of pharmaceutical skeletons.

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Multi-model ensemble learning for battery state-of-health estimation:Recent advances and perspectives

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Journal of Energy Chemistry 2025年第1期100卷 739-759页

作者： Chuanping Lin Jun Xu Delong Jiang Jiayang Hou Ying Liang Zhongyue Zou Xuesong mei State Key Laboratory for Manufacturing Systems Engineering Xi'an Jiaotong University Shaanxi Key Laboratory of Intelligent Robots School of Mechanical Engineering Xi'an Jiaotong University Department of Electrical Engineering and Automation Luoyang Institute of Science and Technology School of Mechanical Engineering Hangzhou Dianzi University

The burgeoning market for lithium-ion batteries has stimulated a growing need for more reliable battery performance monitoring. Accurate state-of-health(SOH) estimation is critical for ensuring battery operational performance. Despite numerous data-driven methods reported in existing research for battery SOH estimation, these methods often exhibit inconsistent performance across different application scenarios. To address this issue and overcome the performance limitations of individual data-driven models,integrating multiple models for SOH estimation has received considerable attention. Ensemble learning(EL) typically leverages the strengths of multiple base models to achieve more robust and accurate outputs. However, the lack of a clear review of current research hinders the further development of ensemble methods in SOH estimation. Therefore, this paper comprehensively reviews multi-model ensemble learning methods for battery SOH estimation. First, existing ensemble methods are systematically categorized into 6 classes based on their combination strategies. Different realizations and underlying connections are meticulously analyzed for each category of EL methods, highlighting distinctions, innovations, and typical applications. Subsequently, these ensemble methods are comprehensively compared in terms of base models, combination strategies, and publication trends. Evaluations across 6 dimensions underscore the outstanding performance of stacking-based ensemble methods. Following this, these ensemble methods are further inspected from the perspectives of weighted ensemble and diversity, aiming to inspire potential approaches for enhancing ensemble performance. Moreover, addressing challenges such as base model selection, measuring model robustness and uncertainty, and interpretability of ensemble models in practical applications is emphasized. Finally, future research prospects are outlined, specifically noting that deep learning ensemble is poised to advance ens

关键词： Contrastive Learning

8-ranks of Class Groups of Some Imaginary Quadratic Number Fields

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Acta Mathematica Sinica,English Series 2007年第11期23卷 2061-2068页

作者： xi mei WU Department of Mathematics Nanjing University of Aeronautics and AstronauticsNanjing 210016 P. R. China State Key Laboratory of Information Security Graduate School of Chinese Academy of Sciences Beijing 100039 P. R. China

Let F = Q（√-p1p2） be an imaginary quadratic field with distinct primes p1 = p2 = 1 mod 8 and the Legendre symbol （p1/p2） = 1. Then the 8-rank of the class group of F is equal to 2 if and only Pl if the following conditions hold：（1） The quartic residue symbols （p1/p2）4 = （p2/p1）4 = 1; （2） Either both p1 and p2 are represented by the form a^2 ＋ 32b^2 over Z and p^h2＋（2p1）/4=x^2-2p1y^2,x,y∈Z,or both p1 and p2 are not represented by the form a^2 ＋ 32b^2 over Z and p^h2＋（2p1）/4=ε（2x^2-p1y^2）,x,y∈Z,ε∈{±1},where h＋（2p1） is the narrow class number of Q（√2p1）,Moreover, we also generalize these results.

关键词： class group Rédei matrix reciprocity law

Effect of the Double Frequency of Trap Field in a Paul Trap

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Communications in Theoretical Physics 2001年第11期36卷 593-596页

作者： NIE zong-xiu FENG Mang LI Jiao-mei SHI Lei ZHU xi-Wen GAO Ke-Lin State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics Wuhan Institute of Physics and MathematicsThe Chinese Academy of SciencesWuhan 430071China

The effect of double frequency oftrap fieldφ=U-V1 cosΩt-V2 cos 2Ωt in a Paul trap can be described exactly by using a function series expansion to solve the corresponding Mathieu *** stability regions of a trapped ... 详细信息

关键词： double frequency trap field Paul trap

Theoretical Study of Haloacetonitrile Anions： CH2XCN^- （X=F, Cl）

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Chinese Journal of Chemical Physics 2008年第3期21卷 255-262页

作者： xin-wen Zhang mei Li Shan-xi Tian Hefei National Laboratory for Physical Sciences at Microscale University of Science and Technologyof China Hefei 230025 China Department of Chemical Physics University of Science and Technology of China Hefei 230026China

Haloacetonitrile anions CH2XCN- （X=F, Cl） were studied by HF-SCF, Becke3-LYP, and MP2 methods together with the Dunning＇s basis set aug-cc-PVTZ. The vertical electron attachments to the neutral are endothermic. The geometrically optimized CH2FCN^- is mainly a valence-bounded anion and CH2FCN→CH2CN＋F^- is a nonadiabatic dissociation. This theoretical study in good agreement with the experimental results shows that the Becke3-LYP method is reasonable in describing the electronic structures of anions and dissociative attachment dynamics, while significant differences between MP2 and Becke3-LYP results are shown for the dissociation potential curves of CH2ClCN→CH2CN＋Cl^-.

关键词： Haloacetonitrile Electron attachment Dissociation dynamics Electron correlation effect

A Note on Calculation of Threshold Resonance by the Method of Complex Scaling

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Chinese Physics Letters 1996年第4期13卷 241-244页

作者： ZHAO mei-shan xiE xi-shun The Janies Franck Institute The University of ChicagoChicagoIllinois 60637USA Department of Physics University of MinnesotaMinneapolisMinnesota 55455USA Department of Physics Southeastern UniversityNanjing210096

A new approach to threshold resonance calculation by the complex scaling method is *** to scattering over a model potential barrier is presented and compared to a direct quantum scattering calculation.

关键词： calculation. scaling quantum

Two-Level Linear Clustering Protocol Based on Wireless Sensor Networks

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Journal of Electronic Science and Technology 2016年第3期14卷 257-261页

作者： mei Hu Yong-xi Wang the School of Electronic and Information Engineering Lanzhou Institute of TechnologyLanzhou 730050China

Aiming at the defects of the nodes in the low energy adaptive clustering hierarchy （LEACH） protocol, such as high energy consumption and uneven energy consumption, a two-level linear clustering protocol is built. The protocol improves the way of the nodes distribution at random. The terminal nodes which have not been a two-level cluster head in the cluster can compete with the principle of equivalent possibility, and on the basis of the rest energy of nodes the two-level cluster head is selected at last. The single hop within the cluster and single hop or multiple hops between clusters are used. Simulation experiment results show that the performance of the two-level linear clustering protocol applied to the Hexi corridor agricultural field is superior to that of the LEACH protocol in the survival time of network nodes, the ratio of success, and the remaining energy of network nodes.

关键词： Clustering energy-efficient farmland Hexi corridor low energy adaptive clustering hierarchy (LEACH) linear wireless sensor network (WSN).

Effects of the shape and size of rectangular inclusions on the fatigue cracking behavior of ultra-high strength steels

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International Journal of Minerals,Metallurgy and Materials 2013年第4期20卷 360-364页

作者： Yan-ping Zeng Hong-mei Fan xi-shan xie School of Materials Science and Engineering University of Science and Technology Beijing

The fatigue cracking behavior of ultra-high strength steels containing rectangular inclusions of small sizes were investigated based on in situ observations by scanning electron microscopy （SEM）. The size and shape of rectangular inclusions affect markedly the initiation site and propagation path of a fatigue crack. Especially, the initiation site of a fatigue crack depends strongly on the angle between the long-axis of a rectangle inclusion and the loading direction, and the length/width ratio of this rectangle inclusion because the residual stress distribution fields vary with these conditions. The results coincide very well with those of finite element analysis.

关键词： high strength steel inclusions fatigue of materials crack initiation crack propagation