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Frontiers of Structural and Civil engineering 2022年第2期16卷 239-249页

作者： Pengfei LI Jinquan zhang Shengqi MEI zhenhua DONG Yan MAO Bridge and Tunnel technology Research Center Research Institute of HighwayMinistry of TransportBeijing100088China National engineering laboratory of Bridge Structure Safety technology Research Institute of HighwayMinistry of TransportBeijing100088China State key laboratory of mechanical Behavior and System Safety of Traffic engineering Structures Shijiazhuang Tiedao UniversityShijiazhuang050043China school of Civil engineering Shijiazhuang Tiedao UniversityShijiazhuang050043China

Damping is known to have a considerable influence on the dynamic behavior of *** fixed damping ratios recommended in design codes do not necessarily represent the complicated damping characteristics of bridge *** study investigated the application of stress-dependent damping associated with vehicle-bridge coupling vibration and based on that investigation proposed the stress-dependent damping *** results of the investigation show that the stress-dependent damping ratio is significantly different from the constant damping ratio(5%)defined in the standard *** vehicles travel at speeds of 30,60,and 90,the damping ratios of the bridge model are 3.656%,3.658%,and 3.671%,*** peak accelerations using the regular damping ratio are 18.9%,21.3%,and 14.5%of the stress-dependent damping ratio,*** the vehicle load on the bridge is doubled,the peak acceleration of the mid-span node increases by 5.4 times,and the stress-related damping ratio increases by 2.1%.A corrugated steel-web bridge is being used as a case study,and the vibration response of the bridge is compared with the measured *** acceleration response of the bridge which was calculated using the stress-dependent damping ratio is significantly closer to the measured acceleration response than that using the regular damping ratio.

关键词： vehicle-bridge vibration system dynamic analysis stress-dependent damping energy dissipation

High-strength and thermally stable TiB_(2)-modified Al-Mn-Mg-Er-Zr alloy fabricated via selective laser melting

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International Journal of Minerals,Metallurgy and Materials 2024年第10期31卷 2221-2232页

作者： Jiang Yu Yaoxiang Geng Yongkang Chen Xiao Wang Zhijie zhang Hao Tang Junhua Xu Hongbo Ju Dongpeng Wang school of Materials Science and engineering Jiangsu University of Science and TechnologyZhenjiang 212003China beijing Advanced Innovation Center for Materials Genome engineering Institute for Advanced Materials and TechnologyUniversity of Science and Technology BeijingBeijing 100083China National engineering Research Center of Near-Net Shape Forming for Metallic Materials Guangdong Provincial Key Laboratory for Processing and Forming of Advanced Metallic MaterialsSouth China University of TechnologyGuangzhou 510640China CEMMPRE-Centre for mechanical engineering Materials and Processes Department of Mechanical EngineeringUniversity of CoimbraRua Luís Reis SantosCoimbra 3030-788Portugal

To increase the processability and plasticity of the selective laser melting(SLM)fabricated Al-Mn-Mg-Er-Zr alloys,a novel TiB_(2)-modified Al-Mn-Mg-Er-Zr alloy with a mixture of Al-Mn-Mg-Er-Zr and nano-TiB_(2) powders was fabricated by *** pro-cessability,microstructure,and mechanical properties of the alloy were systematically investigated by density measurement,microstruc-ture characterization,and mechanical properties *** alloys fabricated at 250 W displayed higher relative densities due to a uni-formly smooth top surface and appropriate laser energy *** maximum relative density value of the alloy reached(99.7±0.1)%,demonstrating good *** alloy exhibited a duplex grain microstructure consisting of columnar regions primarily and equiaxed regions with TiB_(2),Al6Mn,and Al3Er phases distributed along the grain *** directly aging treatment at a high tem-perature of 400℃,the strength of the SLM-fabricated TiB_(2)/Al-Mn-Mg-Er-Zr alloy increased due to the precipitation of the secondary Al6Mn *** maximum yield strength and ultimate tensile strength of the aging alloy were measured to be(374±1)and(512±13)MPa,*** SLM-fabricated TiB_(2)/Al-Mn-Mg-Er-Zr alloy demonstrates exceptional strength and thermal stability due to the synergistic effects of the inhibition of grain growth,the incorporation of TiB_(2) nanoparticles,and the precipitation of secondary Al6Mn nanoparticles.

关键词： selective laser melting aluminum alloy processability mechanical properties thermal stability

STATNet:One-stage coal-gangue detector based on deep learning algorithm for real industrial application

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Energy and AI 2024年第3期17卷 113-125页

作者： Kefei zhang a Teng Wang Xiaolin Yang Liang Xu Jesse Thé Zhongchao Tan Hesheng Yu key laboratory of Coal Processing and Efficient Utilization of Ministry of Education School of Chemical Engineering and TechnologyChina University of Mining and TechnologyXuzhouJiangsu 221116China Department of mechanical&Mechatronics engineering University of Waterloo200 University Avenue WestWaterlooOntario N2L 3G1Canada Lakes Environmental Research Inc. 170 Columbia St.W.Suite 1WaterlooOntarioN2L 3L3 Canada Eastern institute for Advanced Study Eastern Institute of TechnologyNingboZhejiang 315200China Department of Energy and Power engineering Tsinghua UniversityBeijing 100084China

Coal-gangue object detection has attracted substantial attention because it is the core of realizing vision-based intelligent and green coal separation. However, most existing studies have been focused on laboratory datasets and prioritized model lightweight. This makes the coal-gangue object detection challenging to adapt to the complex and harsh scenes of real production environments. Therefore, our project collected and labeled image datasets of coal and gangue under real production conditions from a coal preparation plant. We then designed a one-stage object model, named STATNet, following the “backbone-neck-head” architecture with the aim of enhancing the detection accuracy under industrial coal preparation scenarios. The proposed model utilizes Swin Transformer as backbone module to extract multi-scale features, improved path augmentation feature pyramid network (iPAFPN) as neck module to enrich feature fusion, and task-aligned head (TAH) as head module to mitigate conflicts and misalignments between classification and localization tasks. Experimental results on a real-world industrial dataset demonstrate that the proposed STATNet model achieves an impressive AP50 of 89.27 %, significantly surpassing several state-of-the-art baseline models by 2.02 % to 5.58 %. Additionally, it exhibits stronger robustness in resisting image corruption and perturbation. These findings demonstrate its promising prospects in practical coal and gangue separation applications.

关键词： Coal-gangue detection Swin transformer Impr oved path augmentation feature pyranid network Task-aligned head Object detection

Synergistically enhanced dielectric, insulating and thermally conductive performances of sandwich PMMA based dielectric films

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Progress in Natural Science:Materials International 2024年第3期34卷 591-597页

作者： Dongmei zhang Yufan Li Yuchao Li Zhonggui Sun Hanxue Zhu Lujia Yang Yanhu Zhan Yankai Li Shi Wang Jun-Wei Zha school of Mathematical Sciences Liaocheng University school of Materials Science and engineering Liaocheng University State key laboratory of Organic Electronics and Information Displays & institute of Advanced Materials (IAM) Nanjing University of Posts & Telecommunications school of Chemistry and Biological engineering University of Science and Technology Beijing

A tri-layered(B-G-B) dielectric films were simply prepared by alternatively spin-coating boron nitride/polymethylmethacrylate(BN/PMMA, B) and graphene nanosheets(GNS/PMMA, G) compound solutions. The structure, morphology, thermal conductivity, and particularly the dielectric and relaxation behaviors were systematically studied. Results showed that a good exfoliation and dispersion of BN and GNS can be simply achieved through intensive mechanical compounding with PMMA in the internal mixer. The dielectric constant and breakdown strength of the obtained 1-3-1(B-G-B) sandwich composite film reached 4.3(@1 kHz) and 458.6kV/mm, being 119 % and 113 % higher than that of pure PMMA, respectively. Furthermore, the overall thermal conductivity of sandwich 1-3-1 composite increased by 112 % due to the addition of thermally conductive BN and GNS. The sandwich design strategy provided an effective way of achieving good permittivity, high insulation, and improved thermal conductivity simultaneously, showing potential applications in the miniaturization and integration of electronic devices.

关键词： Breakdown strength Composites Dielectric constant Sandwich structure Thermal conductivity

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高功率化学电源体系发展及军事应用分析

储能科学与技术 2024年第2期13卷 436-461页

作者：李珂郝奕帆方振华王静张松通祝夏雨邱景义明海燕山大学环境与化学工程学院河北秦皇岛066004 轻工业化学电源研究所江苏苏州215600 军事科学院防化研究院北京100191

在全面电动化的背景下,各类电子产品应用的时空域快速转变对所配备的电池供电能力提出了更为苛刻的工况和环境适应要求,亟待发展充电时间短、小体积大电流输出的电源系统。本综述对近年来受到广泛关注的高功率化学电源体系在大倍率充放... 详细信息

在全面电动化的背景下,各类电子产品应用的时空域快速转变对所配备的电池供电能力提出了更为苛刻的工况和环境适应要求,亟待发展充电时间短、小体积大电流输出的电源系统。本综述对近年来受到广泛关注的高功率化学电源体系在大倍率充放电领域的进展进行了梳理,包括锂离子电池、钠离子电池、赝电容电容器、离子型电容器(锂/钠/钾离子等)、铅炭电池等,分别从电极材料、电解质调控和电池结构等角度出发,重点分析了当前影响各电源体系在其功率性能方面的发展瓶颈、能力水平以及亟待突破的关键技术,并对其在低温启动、动力供电和脉冲响应等军事应用领域及所增益效能进行了分析研究。综合分析表明,针对不同的应用场景,为进一步遴选性能更好、更匹配的化学电源体系服务于装备的迭代升级和应用创新,通过构筑高稳定性和导电性的电极材料,宽温域、高电导率的电解质材料和改良电池结构从而减小内阻的途径,显著提升功率性能,并明确提出高功率电池存在最佳工作区间和最优工作策略的问题,尤其是在大电流充放电和脉冲工况下,这对于后续如何根据实际工况用好电池具有借鉴意义。有望在提升各化学电源体系的功率性能的同时,以最佳的系统管控方法和应用策略进一步提升电池的循环寿命、能量转换效率、安全性和可靠性,获得满足市场所需和军民急用的高功率电源产品。

关键词：高功率锂离子电池钠离子电池电容器铅炭电池军事应用

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通过高通量研究识别用于本征陡坡晶体管的原子级薄孤立能带沟道材料

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Science Bulletin 2024年第10期69卷 1427-1436页

作者：屈恒泽张胜利曹江吴振华柴扬李卫胜李连忠任文才王欣然曾海波 MIIT key laboratory of Advanced Display Materials and Devices College of Material Science and EngineeringNanjing University of Science and TechnologyNanjing 210094China school of Electronic and Optical engineering Nanjing University of Science and TechnologyNanjing 210094China key laboratory of Microelectronics Device and Integrated technology Institute of Microelectronics of Chinese Academy of SciencesBeijing 100029China Department of Applied Physics The Hong Kong Polytechnic UniversityHong Kong 999077China National laboratory of Solid State Microstructures School of Electronic Science and Engineering and Collaborative Innovation Center of Advanced MicrostructuresNanjing UniversityNanjing 210023China Department of mechanical engineering The University of Hong KongHong Kong 999077China Shenyang National laboratory for Materials Science Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China school of Integrated Circuits Nanjing UniversitySuzhou 215163China Suzhou laboratory Suzhou 215009China

Developing low-power FETs holds significant importance in advancing logic circuits,especially as the feature size of MOSFETs approaches sub-10 ***,this has been restricted by the thermionic limitation of SS,which is limited to 60 mV per decade at room ***,we proposed a strategy that utilizes 2D semiconductors with an isolated-band feature as channels to realize subthermionic SS in *** high-throughput calculations,we established a guiding principle that combines the atomic structure and orbital interaction to identify their sub-thermionic transport *** guides us to screen 192 candidates from the 2D material database comprising 1608 ***,the physical relationship between the sub-thermionic transport performances and electronic structures is further revealed,which enables us to predict 15 systems with promising device performances for low-power applications with supply voltage below 0.5 *** work opens a new way for the low-power electronics based on 2D materials and would inspire extensive interests in the experimental exploration of intrinsic steep-slope MOSFETs.

关键词： 2D materials Electronic band structures Transport properties Steep-slope transistors DFT-NEGF calculations

Concurrent hetero-/homo-geneous electrocatalysts to bi-phasically mediate sulfur species for lithium-sulfur batteries

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Journal of Energy Chemistry 2024年第6期93卷 663-668,I0016页

作者： Rui-Bo LingHu Jin-Xiu Chen Jin-Hao zhang Bo-Quan Li Qing-Shan Fu Gulnur Kalimuldina Geng-Zhi Sun Yunhu Han Long Kong Xi’an institute of Flexible Electronics(IFE) Northwestern Polytechnical UniversityXi’an 710129ShaanxiChina institute of Advanced Materials Nanjing Tech UniversityNanjing 211816JiangsuChina Advanced Research institute of Multidisciplinary Science Beijing Institute of TechnologyBeijing 100081China Department of mechanical and Aerospace engineering School of Engineering and Digital SciencesNazarbayev UniversityKabanbay Batyr Ave.53Astana 010000Kazakhstan

Expediting redox kinetics of sulfur species on conductive scaffolds with limited charge accessible surface is considered as an imperative approach to realize energy-dense and power-intensive lithium-sulfur(Li-S)*** this work,the concept of concurrent hetero-/homo-geneous electrocatalysts is proposed to simultaneously mediate liquid-solid conversion of lithium polysulfides(LiPSs)and solid lithium disulfide/sulfide(Li_(2)S_(2)/Li_(2)S)propagation,the latter of which suffers from sluggish reduction kinetics due to buried conductive scaffold surface by extensive deposition of Li_(2)S_(2)/Li_(2)*** selected model material to verify this concept is a two-in-one catalyst:carbon nanotube(CNT)scaffold supported iron-cobalt(Fe-Co)alloy nanoparticles and partially carbonized selenium(C-Se)*** Fe-Co alloy serves as a heterogeneous electrocatalyst to seed Li_(2)S_(2)/Li_(2)S through sulphifilic active sites,while the C-Se sustainably releases soluble lithium polyselenides and functions as a homogeneous electrocatalyst to propagate Li_(2)S_(2)/Li_(2)S via solution *** bi-phasic mediation of the sulfur species benefits reduction kinetics of LiPS conversion,especially for the massive Li_(2)S_(2)/Li_(2)S growth scenario by affording an additional solution directed route in case of conductive surface being largely *** strategy endows the Li-S batteries with improved cycling stability(836 mA h g^(-1)after 180 cycles),rate capability(547 mA h g^(-1)at 4 C)and high sulfur loading superiority(2.96 mA h cm^(-2)at 2.4 mg cm^(-2)).This work hopes to enlighten the employment of bi-phasic electrocatalysts to dictate liquid-solid transformation of intermediates for conversion chemistry batteries.

关键词： Lithium-sulfur batteries Electrocatalysis Lithium polysulfides Sulfur cathode Energy density

Frontiers in high entropy alloys and high entropy functional materials

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Rare Metals 2024年第10期43卷 4639-4776页

作者： Wen-Tao zhang Wen Huang Fu-Jie Yu Qi Zhao Xin-Dong Zhu Tao Feng Yao Jiang Xiao-Ming Li Xue-Fei Miao He Zhu Si Lan Xue-Qian Wang Bao-Long Shen Zhe Jia Feng-Qi zhang Wei Wang Qi Liu Yang Ren Xun-Li Wang Xiao-Ya Cui Xiao-Yang Wang Ya-Nan Chen Bing-Bing Fan Meng-Ru Li Qi-Long Gao Jia-Ming Guo Zeng-Bao Jiao Zhi-Min Guo Yu-Ping Zhao Qian Yu Rui Huang Ling-Kun zhang Yi-Ping Lu Xu-Bo Li Huai-Jun Lin Yan Ma Wei-Ming Yang Zhi-Hua Shen Hai-Yan He Yong-Gang Sun Yong-Jiang Huang De-Zhuang Wang Qing-Feng Liu Fei-Yang Wang Hui Liu Hong-Hui Wu Li-Qiang Wang Yang Lu Nan Wang Tian-Li Wang Wei-Bing Liao Yi-Han Wang Yuan Wu Yu-Zhen Yin Jie Pan Yi zhang Qing Wang Jian-Yang zhang Tao Yang Yasir Sohail Jin-Yu zhang Hua Ji Qiang Li Wei-Di Liu Zhi-Gang Chen Xiong-Jun Liu Wen Ma Liang Mao Zhen-Duo Wu school of Materials Science and engineering Nanjing University of Science and Technology jiangsu key laboratory for Advanced Metallic Materials School of Materials Science and Engineering Southeast University Department of Physics City University of Hong Kong school of Materials Science and engineering Tianjin University school of Physics and Microelectronics Zhengzhou University Department of mechanical engineering Research Institute for Advanced Manufacturing The Hong Kong Polytechnic University Center of Electron Microscopy and State key laboratory of Silicon Materials School of Materials Science and Engineering Zhejiang University key laboratory of Solidification Control and Digital Preparation technology (Liaoning Province) School of Materials Science and Engineering Dalian University of Technology institute of Advanced Wear & Corrosion Resistance and Functional Materials Jinan University school of Mechanics and Civil engineering China University of Mining and Technology school of Physical Sciences Great Bay University school of Materials Science andengineering Harbin Institute of Technology State key laboratory of Materials-Oriented Chemical engineering College of Chemical Engineering Nanjing Tech University beijing Advanced Innovation Center for Materials Genome engineering Research Institute for Carbon Neutrality University of Science and Technology Beijing Department of mechanical engineering The University of Hong Kong school of Computing Macquarie University key laboratory of Optoelectronic Devices and Systems of Ministry of Education and Guangdong Province College of Physics and Optoelectronic Engineering Shenzhen University State key laboratory for Advanced Metals and Materials University of Science and Technology Beijing State key laboratory of Materials Processing and Die & Mould technology School of Materials Science and Engineering Huazhong University of Science and Technology institute of materials Shanghai University Department of Materials Science and engineering C

Owing to their exceptional properties, high-entropy alloys(HEAs) and high-entropy materials have emerged as promising research areas and shown diverse applications. Here,the recent advances in the field are comprehensively reviewed,organized into five sections. The first section introduces the background of HEAs, covering their definition, significance,application prospects, basic properties, design principles, and microstructure. The subsequent section focuses on cutting-edge high-entropy structural materials, highlighting developments such as nanostructured alloys, grain boundary engineering,eutectic systems, cryogenic alloys, thin films, micro-nano-lattice structures, additive manufacturing, high entropy metallic glasses, nano-precipitate strengthened alloys, composition modulation, alloy fibers, and refractory systems. In the following section, the emphasis shifts to functional materials, exploring HEAs as catalysts, magneto-caloric materials, corrosion-resistant alloys, radiation-resistant alloys, hydrogen storage systems, and materials for biomedicine. Additionally, the review encompasses functional high-entropy materials outside the realm of alloys, including thermoelectric, quantum dots, nanooxide catalysts, energy storage materials, negative thermal expansion ceramics,and high-entropy wave absorption materials. The paper concludes with an outlook, discussing future directions and potential growth areas in the field. Through this comprehensive review,researchers, engineers, and scientists may gain valuable insights into the recent progress and opportunities for further exploration in the exciting domains of high-entropy alloys and functional materials.

关键词： Cutting-edge structural materials Cutting-edgefunctional materials High entropy alloys

Graphene binding on black phosphorus enables high on/off ratios and mobility

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National Science Review 2024年第2期11卷 188-195页

作者： Fanrong Lin Zhonghan Cao Feiping Xiao Jiawei Liu Jiabin Qiao Minmin Xue Zhili Hu Ying Liu Huan Lu Zhuhua zhang Jens Martin Qingjun Tong Wanlin Guo Yanpeng Liu key laboratory for Intelligent Nano Materials and Devices of Ministry of Education State Key Laboratory of Mechanics and Control of Mechanical Structures and Institute for Frontier Science Nanjing University of Aeronautics and Astronautics Centre for Advanced 2D Materials National University of Singapore school of Physics and Electronics Hunan University Centre for Quantum Physics Key Laboratory of Advanced Optoelectronic Quantum Architecture and MeasurementSchool of PhysicsBeijing Institute of Technology Leibniz institute für Kristallzüchtung

Graphene is one of the most promising candidates for integrated circuits due to its robustness against short-channel effects, inherent high carrier mobility and desired gapless nature for Ohmic contact, but it is difficult to achieve satisfactory on/off ratios even at the expense of its carrier mobility, limiting its device applications. Here, we present a strategy to realize high back-gate switching ratios in a graphene monolayer with well-maintained high mobility by forming a vertical heterostructure with a black phosphorus multi-layer. By local current annealing, strain is introduced within an established area of the graphene, which forms a reflective interface with the rest of the strain-free area and thus generates a robust off-state via local current depletion. Applying a positive back-gate voltage to the heterostructure can keep the black phosphorus insulating, while a negative back-gate voltage changes the black phosphorus to be conductive because of hole accumulation. Then, a parallel channel is activated within the strain-free graphene area by edge-contacted electrodes, thereby largely inheriting the intrinsic carrier mobility of graphene in the on-state. As a result, the device can provide an on/off voltage ratio of >10～3 as well as a mobility of ～8000 cm2V-1s-1at room temperature, meeting the low-power criterion suggested by the International Roadmap for Devices and Systems.

关键词： graphene on/off ratio mobility black phosphorus reflective interface