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Acta Metallurgica Sinica(English Letters) 2024年第2期37卷 255-265页

作者： x.Y.Yue S.Y.peng x.Zhang C.N.He Y.Z.Tian Key Laboratory for Anisotropy and Texture of Materials(Ministry of Education) School of Materials Science and EngineeringNortheastern UniversityShenyang110819China School of Materials Science and Engineering and Tianjin Key Laboratory of Composite and Functional Materials Tianjin UniversityTianjin300350China Research Centre for Metallic Wires Northeastern UniversityShenyang110819China

A Cu-10wt%Fe composite was prepared through hot-pressed sintering,and the material was subsequently solution *** hot-pressed sintered and solution treated materials were rolled and *** precipitation behavior and performance changes were systematically studied by using scanning electron microscopy and transmission electron *** contrast to the hot-pressed sintered specimen,the solution treatment significantly affects the thermal stability and properties of the Cu-10wt%Fe *** Cu-10wt%Fe composite was prepared after solid solution,cold rolling and aging at 773 K for 1 h,and it obtained excellent tensile strength of 494 MPa,uniform elongation of 16.3%,electrical conductivity of 51.1%IACS and softening temperature of 838 *** for the distinct difference in thermal stability and properties between hot-pressed sintered and solution treated specimens were *** findings provide a theoretical basis for designing high-performance Cu-based in-situ composites by post treatment.

关键词： Cu-Fe composite Hot-pressed sintering Thermal stability Strength Electrical conductivity

Layer Hall effect induced by hidden Berry curvature in antiferromagnetic insulators

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National Science Review 2024年第2期11卷 15-23页

作者： Rui Chen Hai-peng Sun Mingqiang Gu Chun-Bo Hua Qihang Liu Hai-Zhou Lu x.C.xie Shenzhen Institute for Quantum Science and Engineering and Department of Physics Southern University of Science and Technology(SUSTech) International Quantum Academy Institute for Theoretical Physics and Astrophysics University of Würzburg School of Electronic and Information Engineering Hubei University of Science and Technology Guangdong Provincial Key Laboratory of Computational Science and Material Design Southern University of Science and Technology Shenzhen Key Laboratory of Quantum Science and Engineering International Center for Quantum Materials School of PhysicsPeking University Collaborative Innovation Center of Quantum Matter CAS Center for Excellence in Topological Quantum Computation University of Chinese Academy of Sciences

The layer Hall effect describes electrons spontaneously deflected to opposite sides at different layers, which has been experimentally reported in the MnBi2Te4thin films under perpendicular electric fields. Here, we reveal a universal origin of the layer Hall effect in terms of the so-called hidden Berry curvature, as well as material design principles. Hence, it gives rise to zero Berry curvature in momentum space but non-zero layer-locked hidden Berry curvature in real space. We show that, compared to that of a trivial insulator, the layer Hall effect is significantly enhanced in antiferromagnetic topological insulators. Our universal picture provides a paradigm for revealing the hidden physics as a result of the interplay between the global and local symmetries, and can be generalized in various scenarios.

关键词： layerHall effect hidden Berry curvature antiferromagnetic insulator axion insulator, quantum transport

A time-space network-based model for transportation service optimization of China Railway Express

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High-speed Railway 2024年第3期2卷 153-163页

作者： Yin W. Hu W. Yan x. peng B. Yang x. College of Urban Rail Transit and Logistics Beijing Union University Beijing 100101 China School of Traffic and Transportation Beijing Jiaotong University Beijing 100044 China International School of Economics and Management Capital University of Economics and Business Beijing 100070 China

This paper describes the development and optimization plans for the China Railway Express (CR Express). As a new type of international land transport organization, CR Express has emerged with the continuous expansion of China toward European investment and trade, and in particular, has expanded with the continuous progress of the One Belt and One Road (OBOR) initiative. In addition to improving the service quality of CR Express, the operating costs must be reduced for developing “smart railways” that serve “smart cities”. We propose a dual-objective-based function mathematical optimization model; the satisfaction of the cargo owner is considered, and the timeliness, transportation capacity, and goods category constraints of CR Express transportation are designed. Moreover, we present the normalized equivalent method of the two-objective function of the model. Finally, a case study is conducted against the background of certain trains in the western corridor of CR Express to validate the effectiveness of the model and research methods proposed in this study. © 2024 Beijing Jiaotong University

关键词： China Railway Express Mathematical optimization One Belt and One Road Time-space network Transportation service

Ka-band thin film lithium niobate photonic integrated optoelectronic oscillator

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Photonics Research 2024年第6期12卷 1283-1293页

作者： RUI MA ZIJUN HUANG SHENGQIAN GAO JINGYI WANG xICHEN WANG xIAN ZHANG peng HAO x.STEVE YAO xINLUN CAI State Key Laboratory of Optoelectronic Materials and Technologies School of Electronics and Information TechnologySun Yat-sen UniversityGuangzhou 510275China Photonics Information Innovation Center and Hebei Provincial Center for Optical Sensing College of Physics Science and TechnologyHebei UniversityBaoding 071002China NuVison Photonics Inc.Las VegasNevada 89109USA

Photonics integration of an optoelectronic oscillator(OEO)on a chip is attractive for fabricating low cost,compact,low power consumption,and highly reliable microwave sources,which has been demonstrated recently in silicon on insulator(SOI)and indium phosphide(InP)platforms at x-band around 8 *** we demonstrate the first integration of OEOs on the thin film lithium niobate(TFLN)platform,which has the advantages of lower Vπ,no chirp,wider frequency range,and less sensitivity to *** have successfully realized two different OEOs operating at Ka-band,with phase noises even lower than those of the x-band OEOs on SOI and InP *** is a fixed frequency OEO at 30 GHz realized by integrating a Mach–Zehnder modulator(MZM)with an add-drop microring resonator(MRR),and the other is a tunable frequency OEO at 20–35 GHz realized by integrating a phase modulator(PM)with a notch *** work marks the first step of using TFLN to fabricate integrated OEOs with high frequency,small size,low cost,wide range tunability,and potentially low phase noise.

关键词： optoelectronic modulator resonator

Numerical simulation of fluid flow and free surface fluctuations during wheel and belt casting process

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Journal of Iron and Steel Research International 2024年第5期31卷 1117-1126页

作者： Kun Gao Yan peng National Engineering Research Center for Equipment and Technology of Cold Strip Rolling Yanshan UniversityQinhuangdao066004HebeiChina

The unstable fluid flow and severe free surface fluctuations in the wheel and belt caster can affect the quality of the cast *** lower level height tends to entrap inclusions in the molten *** the other hand,the higher level height makes the production process more dangerous due to the overflow of high temperature fluid from the mold.A computational model of the molten metal pouring process was *** transient fluid flow and free surface fluctuations behavior were calculated using the three-dimensional large eddy simulation model and the volume of fluid *** results show that the flow velocity of the main jet gradually decreases under the influence of the low kinetic energy fluid in the *** is an obvious oscillation in the tail of the jet,while the flow field is asymmetric in *** jet is closer to the inside radius side due to the Coanda effect,and there is a recirculation zone on the inside radius and the outside radius respectively,according to the 10 s time-averaged *** with the industrial observation and simulation results,the shape of the free surface is a wave that varies with *** addition,the free surface height is lowest and the flow velocity is highest in the region near the jet.

关键词： Fluid flow Free surface Wheel and belt caster Large eddy simulation Volume of fluid method

Accelerated water harvesting from vapor via a bio-inspired hydrogel pattern

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National Science Review 2024年第3期11卷 48-49页

作者： Lianbin Zhang peng Wang State Key Laboratory of Material Processing and Die&Mould Technology Key Laboratory of Materials Chemistry for Energy Conversion and Storage of Ministry of Education School of Chemistry and Chemical Engineering Huazhong University of Science and Technology(HUST) School of Environmental Science and Engineering Sun Yat-sen University

Water and energy sustainability are integral parts of resource sustainability of the world. Due to water molecules' superior capability of serving as both hydrogenbond donor and acceptor, phase change of water, especially between liquid and vapor, underpins global water cycles,facilitates energy transformation and transfer, and thus helps shape the unique local weather and global climate patterns.

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Divergent contributions of spring and autumn photosynthetic phenology to seasonal carbon uptake of subtropical vegetation in China

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Journal of Geographical Sciences 2024年第7期34卷 1280-1296页

作者： peng Ying LI peng ZHOU xiaolu LUO Yunpeng ZHANG Cicheng WANG Longjun LI Tong peng Changhui School of Geographic Sciences Hunan Normal UniversityChangsha410081China Department for Biogeochemical Integration Max-Planck-Institute for BiogeochemistryJena07745Germany Department of Biology Sciences Institute of Environment SciencesUniversity of Quebec at MontrealC.P.8888Succ.Centre-VilleMontrealH3C 3P8Canada

Phenological changes play a central role in regulating seasonal variation in the ecological processes,exerting significant impacts on hydrologic and nutrient cycles,and ultimately influencing ecosystem functioning such as carbon ***,the potential impact mechanisms of phenological events on seasonal carbon dynamics in subtropical regions are *** knowledge gaps hinder from accurately linking photosynthetic phenology and carbon sequestration *** chlorophyll fluorescence remote sensing and productivity data from 2000 to 2019,we found that an advancement in spring phenology increased spring gross(GPP)and net primary productivity(NPP)in subtropical vegetation of China by 2.1 gC m^(-2)yr^(-1)and 1.4 gC m^(-2)yr^(-1),respectively.A delay in autumn phenology increased the autumnal GPP and NPP by 0.4 gC m^(-2)yr^(-1)and 0.2 gC m^(-2)yr^(-1),***,the contribution of the spring phenology to spring carbon uptake increased significantly during the study period,while this positive contribution showed a nonsignificant trend in *** comparison,the later autumn phenology could significantly contribute to the increase in autumnal carbon uptake;however,this contributing effect was *** analysis indicated that these phenomena have been caused by the increased leaf area and enhanced photosynthesis due to earlier spring and later autumn phenology,*** results demonstrate the diverse impacts of vegetation phenology on the seasonal carbon sequestration ability and it is imperative to consider such asymmetric effects when modeling ecosystem processes parameterized under future climate change.

关键词： subtropics vegetation phenology remote sensing carbon cycle climate change

Edge and lithium concentration effects on intercalation kinetics for graphite anodes

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Journal of Energy Chemistry 2024年第3期90卷 337-347,I0009页

作者： Keming Zhu Denis Kramer Chao peng School of Mechanical and Precision Instrument Engineering Xi'an University of TechnologyXi'an 710048ShanxiChina Faculty of Mechanical Engineering Helmut-Schmidt UniversityHamburg 22043Germany School of Engineering University of SouthamptonSouthampton SO171BJUK Multiscale Crystal Materials Research Center Shenzhen Institute of Advanced TechnologyChinese Academy of SciencesShenzhen 518055GuangdongChina

Graphite interfaces are an important part of the anode in lithium-ion batteries(LIBs),significantly influencing Li intercalation *** anodes adopt different stacking sequences depending on the concentration of the intercalated Li *** this work,we performed first-principles calculations to comprehensively address the energetics and dynamics of Li intercalation and Li vacancy diffusion near the no n-basal edges of graphite,namely the armchair and zigzag-edges,at high Li *** find that surface effects persist in stage-Ⅱ that bind Li strongly at the edge ***,the pronounced effect previously identified at the zigzag edge of pristine graphite is reduced in LiC_(12),penetrating only to the subsurface site,and eventually disappearing in LiC_(6).Consequently,the distinctive surface state at the zigzag edge significantly impacts and restrains the charging rate at the initial lithiation of graphite anodes,whilst diminishes with an increasing degree of *** diffusion time for Li hopping to the bulk site from either the zigzag edge or the armchair edge in LiC_(6) was observed during high state of charge due to charge *** controlling Li occupation and diffusion kinetics at this stage is also crucial for enhancing the charge rate.

关键词： Graphite anode Edge Interface Lithium-ion batteries Density functional theory

Stability assessment of tree ring growth of Pinus armandii Franch in response to climate change based on slope directions at the Lubanling in the Funiu Mountains,China

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Journal of Forestry Research 2024年第3期35卷 197-208页

作者： Jinkuan Li Jianfeng peng xiaoxu Wei Meng peng xuan Li Yameng Liu Jiaxin Li College of Geography and Environmental Science Henan UniversityKaifeng 475004People’s Republic of China Key Laboratory of Earth System Observation and Simulation of Henan Province Kaifeng 475004People’s Republic of China

Global warming will affect growth strategies and how trees will *** compare the response of tree radial growth to climate warming in different slope directions,samples of Pinus armandii Franch were collected and treering chronologies developed on northern and western slopes from the Lubanling in the Funiu *** analyses showed that two chronologies were mainly limited by temperatures in the previous June–August and the combination of temperatures and moisture in the current May–*** difference of the climate response to slopes was small but not *** growth of the LBL01 site on the northern slope was affected by the combined maximum and minimum temperatures,while that of the LBL02 site was affected by maximum *** regards to moisture,radial growth of the trees on the north slope was influenced by the relative humidity in the current May–July,while on the western slope,it was affected by the relative humidity in the previous June–August,the current May–July and the precipitation in the current May–*** the change in climate,the effects of the main limiting factors on growth on different slopes were visible to a certain extent,but the differences in response of trees on different slopes gradually decreased,which might be caused by factors such as different slope directions and the change in diurnal temperature *** results may provide information for forest protection and ecological construction in this region,and a scientific reference for future climate reconstruction.

关键词： Tree ring width Lubanling Pinus armandii Franch Slope direction Climate response

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Gria:an efficient deterministic concurrency control protocol

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Frontiers of Computer Science 2024年第4期18卷 25-37页

作者： xinyuan WANG Yun peng Hejiao HUANG School of Computer Science and Technology Harbin Institute of TechnologyShenzhen 518055China Institute of Artificial Intelligence and Blockchain Guangzhou UniversityGuangzhou 510006China

Deterministic databases are able to reduce coordination costs in a *** property has fostered a significant interest in the design of efficient deterministic concurrency control ***,the state-of-the-art deterministic concurrency control protocol Aria has three ***,it is impractical to configure a suitable batch size when the read-write set is ***,Aria running in low-concurrency scenarios,e.g.,a single-thread scenario,suffers from the same conflicts as running in high-concurrency ***,the single-version schema brings write-after-write *** address these issues,we propose Gria,an efficient deterministic concurrency control *** has the following ***,the batch size of Gria is ***,Gria’s conflict probability in low-concurrency scenarios is lower than that in high-concurrency ***,Gria has no write-after-write conflicts by adopting a multi-version *** further reduce conflicts,we propose two optimizations:a reordering mechanism as well as a rechecking *** evaluation result on two popular benchmarks shows that Gria outperforms Aria by 13x.

关键词： deterministic concurrency control transaction processing