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“Zero‑Strain” NiNb_(2)O_(6) Fibers for All‑Climate Lithium Storage

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Nano-Micro Letters 2025年第1期17卷 348-360页

作者： Yan Zhao Qiang Yuan Liting yang Guisheng Liang Yifeng cheng Limin Wu Chunfu Lin Renchao che College of Physics Donghua UniversityShanghai 201620People’s Republic of China School of Materials Science and Engineering Institute of Materials for Energy and EnvironmentQingdao UniversityQingdao 266071People’s Republic of China Laboratory of Advanced Materials Shanghai Key Laboratory of Molecular Catalysis and Innovative MaterialsAcademy for Engineering&TechnologyFudan UniversityShanghai 200438People’s Republic of China Zhejiang Laboratory Hangzhou 311100People’s Republic of China Inner Mongolia University Hohhot 010021People’s Republic of China

Niobates are promising all-climate Li^(+)-storage anode material due to their fast charge transport,large specific capacities,and resistance to electrolyte ***,their moderate unit-cellvolume expansion(generally 5%–10%)during Li^(+)storage causes unsatisfactory long-term ***,“zero-strain”NiNb_(2)O_(6) fibers are explored as a new anode material with comprehensively good electrochemical *** Li^(+)storage,the expansion of electrochemical inactive NiO_(6) octahedra almost fully offsets the shrinkage of active NbO_(6) octahedra through reversible O *** superior volume-accommodation capability of the NiO_(6) layers guarantees the“zero-strain”behavior of NiNb_(2)O_(6) in a broad temperature range(0.53%//0.51%//0.74%at 25//−10//60℃),leading to the excellent cyclability of the NiNb_(2)O_(6) fibers(92.8%//99.2%//91.1%capacity retention after 1000//2000//1000 cycles at 10C and 25//−10//60℃).This NiNb_(2)O_(6) material further exhibits a large reversible capacity(300//184//318 mAh g−1 at 0.1C and 25//−10//60℃)and outstanding rate performance(10 to 0.5C capacity percentage of 64.3%//50.0%//65.4%at 25//−10//60℃).Therefore,the NiNb_(2)O_(6) fibers are especially suitable for large-capacity,fast-charging,long-life,and all-climate lithium-ion batteries.

关键词： NiNb_(2)O_(6)porous fiber “Zero-strain”mechanism Electrochemical property Harsh-temperature operation Operando characterization

Dynamic event-triggered data-driven iterative learning bipartite tracking control for nonlinear MASs with prescribed performance

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Science China(Information Sciences) 2025年第1期 292-305页

作者： Tao SHI wei-wei che School of Mechatronic Engineering and Automation Shanghai University State Key Laboratory of Synthetical Automation for Process Industries Northeastern University College of Information Science and Engineering Northeastern University

This article proposes a distributed dynamic event-triggered data-driven iterative learning control(DET-DDILC)scheme under a predefined performance to tackle the bipartite tracking control problem for multiagent systems(MASs). An improved dynamic linearization technique is utilized to convert the nonlinear MASs into an iterative linear data model. First,a peer-to-peer mapping function is introduced to map the constrained distributed system output homeomorphism to an unconstrained one. In addition, a DET mechanism based on a time-iteration-varying function is devised to conserve network communication resources. Based on the unconstrained transformation and the designed DET mechanism, the DET-DDILC algorithm is devised to ensure that the bipartite tracking performance of MASs can be within the preset range. Finally, the effectiveness and feasibility of the designed control scheme are demonstrated via a simulation case by a comparison.

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Reinforcement learning-based unknown reference tracking control of HMASs with nonidentical communication delays

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Science China(Information Sciences) 2023年第7期66卷 46-57页

作者： Yong XU Zheng-guang WU wei-wei che Deyuan MENG School of Automation Beijing Institute of Technology Institute of Cyber-Systems and Control Zhejiang University College of Mathematics and Computer Science Zhejiang Normal University Department of Automation Qingdao University School of Automation Science and Electrical Engineering Beihang University(BUAA)

This paper focuses on the optimal output synchronization control problem of heterogeneous multiagent systems(HMASs) subject to nonidentical communication delays by a reinforcement learning *** with existing studies assuming that the precise model of the leader is globally or distributively accessible to all or some of the followers, the leader’s precise dynamical model is entirely inaccessible to all the followers in this paper. A data-based learning algorithm is first proposed to reconstruct the leader’s unknown system matrix online. A distributed predictor subject to communication delays is further devised to estimate the leader’s state, where interaction delays are allowed to be nonidentical. Then, a learning-based local controller, together with a discounted performance function, is projected to reach the optimal output synchronization. Bellman equations and game algebraic Riccati equations are constructed to learn the optimal solution by developing a model-based reinforcement learning(RL) algorithm online without solving regulator equations, which is followed by a model-free off-policy RL algorithm to relax the requirement of all agents’ dynamics faced by the model-based RL algorithm. The optimal tracking control of HMASs subject to unknown leader dynamics and communication delays is shown to be solvable under the proposed RL algorithms. Finally, the effectiveness of theoretical analysis is verified by numerical simulations.

关键词： heterogeneous multiagent systems HMAS reinforcement learning RL optimal output synchronization communication delays

A power-aware code-compression design for RISC/VLIW architecture

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Journal of Zhejiang University-Science C(Computers and Electronics) 2011年第8期12卷 629-637页

作者： che-wei LIN Chang hong LIN wei Jhih WANG Department of Electronic Engineering National Taiwan University of Science and Technology Taiwan 106 Taipei

We studied the architecture of embedded computing systems from the viewpoint of power consumption in memory systems and used a selective-code-compression (SCC) approach to realize our *** on the LZW (Lempel-Ziv-Welch) compression algorithm,we propose a novel cost effective compression and decompression *** goal of our study was to develop a new SCC approach with an extended decision policy based on the prediction of power *** decompression method had to be easily implemented in hardware and to collaborate with the embedded *** hardware implementation of our decompression engine uses the TSMC 0.18μm-2p6m model and its cell-based *** calculate power consumption more accurately,we used a static analysis method to estimate the power overhead of the decompression *** also used variable sized branch blocks and considered several features of very long instruction word (VLIW) processors for our compression,including the instruction level parallelism (ILP) technique and the scheduling of *** code-compression methods are not limited to VLIW machines,and can be applied to other kinds of reduced instruction set computer (RISC) architecture.

关键词： LZW compression Cell-based libraries Instruction level parallelism (ILP) VLIW processors

Nonlinear dynamic analysis of a rotor/bearing/seal system

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2011年第1期12卷 46-55页

作者： wei LI Yi yang De-ren SHENG Jian-hong cheN Yong-qiang che Department of Energy Engineering Zhejiang University Hangzhou 310027 China

In this study a new dynamic model of a rotor system is established based on the Hamilton principle and the finite element method (FEM). We analyze the dynamic behavior of the rotor system with the coupled effects of the nonlinear oil film force, the nonlinear seal force, and the mass eccentricity of the disk. The equations of the motion are solved effectively using the fourth order Runge-Kutta method in MATLAB. The dynamic behavior of the system is illustrated by bifurcation diagrams, largest Lyapunov exponents, phase trajectory diagrams, and Poincaré maps. The numerical results show that the rotational speed of the rotor, the pressure drop in the seal, the seal length, the seal clearance, and the mass eccentricity of the disk are the key parameters that significantly affect the dynamic characteristics of the rotor system. The motion of the rotor system exhibits complex types of periodic, quasi-periodic, double-periodic, multi-periodic, and chaotic vibrations. This analysis can be used to guide the design of seal parameters and to diagnose the vibration of rotor/bearing/seal systems.

关键词： Nonlinear Rotor system Hamilton principle Dynamic Finite element method (FEM)

Spontaneous Orientation Polarization of Anisotropic Equivalent Dipoles Harnessed by Entropy Engineering for Ultra‑Thin Electromagnetic Wave Absorber

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Nano-Micro Letters 2025年第1期17卷 424-438页

作者： honghan Wang Xinyu Xiao Shangru Zhai Chuang Xue guangping Zheng Deqing Zhang Renchao che Junye cheng Liaoning Key Lab of Lignocellulose chemistry and BioMaterials Liaoning Collaborative Innovation Center for Lignocellulosic BiorefinerySchool of Light Industry and Chemical EngineeringDalian Polytechnic UniversityDalian 116034People’s Republic of China School of Life Science and Biotechnology Dalian University of TechnologyDalian 116024People’s Republic of China Department of Mechanical Engineering Hong Kong Polytechnic UniversityHung HomKowloonHong Kong 999077People’s Republic of China School of Materials Science and Engineering Qiqihar UniversityQiqihar 161006People’s Republic of China Laboratory of Advanced Materials Shanghai Key Lab of Molecular Catalysis and Innovative MaterialsAcademy for Engineering&TechnologyFudan UniversityShanghai 200438People’s Republic of China Department of Materials Science Shenzhen MSU-BIT UniversityShenzhen 517182People’s Republic of China

The synthesis of carbon supporter/nanoscale high-entropy alloys(HEAs)electromagnetic response composites by carbothermal shock method has been identified as an advanced strategy for the collaborative competition engineering of conductive/dielectric *** migration modes within HEAs as manipulated by the electronegativity,valence electron configurations and molar proportions of constituent elements determine the steady state and efficiency of equivalent ***,enlightened by skin-like effect,a reformative carbothermal shock method using carbonized cellulose paper(CCP)as carbon supporter is used to preserve the oxygencontaining functional groups(O·)of carbonized cellulose fibers(CCF).Nucleation of HEAs and construction of emblematic shell-core CCF/HEAs heterointerfaces are inextricably linked to carbon metabolism induced by O·.Meanwhile,the electron migration mode of switchable electronrich sites promotes the orientation polarization of anisotropic equivalent *** virtue of the reinforcement strategy,CCP/HEAs composite prepared by 35%molar ratio of Mn element(CCP/HEAs-Mn_(2.15))achieves efficient electromagnetic wave(EMW)absorption of−51.35 dB at an ultra-thin thickness of 1.03 *** mechanisms of the resulting dielectric properties of HEAs-based EMW absorbing materials are elucidated by combining theoretical calculations with experimental characterizations,which provide theoretical bases and feasible strategies for the simulation and practical application of electromagnetic functional devices(e.g.,ultra-wideband bandpass filter).

关键词： High-entropy alloys Carbothermal shock Switchable electron migration modes Emblematic shell-core heterointerfaces Ultra-thin thickness

Improving the efficiency of magnetic coupling energy transfer byetching fractal patterns in the shielding metals

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Frontiers of Information Technology & Electronic Engineering 2016年第1期17卷 74-82页

作者： Qing-feng LI Shao-bo che wei-ming WANG hong-wei HAO Lu-ming LI School of Aerospace Tsinghua University Beijing 100084 China National Engineering Laboratory for Neuromodulation Beijing 100084 China Center of Epilepsy Beijing Institute for Brain Disorders Beijing 100084 China

Thin metal sheets are often located in the coupling paths of magnetic coupling energy transfer(MCET) systems. Eddy currents in the metals reduce the energy transfer efficiency and can even present safety risks. This paper describes the use of etched fractal patterns in the metals to suppress the eddy currents and improve the efficiency. Simulation and experimental results show that this approach is very effective. The fractal patterns should satisfy three features, namely, breaking the metal edge, etching in the high-intensity magnetic field region, and etching through the metal in the thickness direction. Different fractal patterns lead to different results. By altering the eddy current distribution, the fractal pattern slots reduce the eddy current losses when the metals show resistance effects and suppress the induced magnetic field in the metals when the metals show inductance effects. Fractal pattern slots in multilayer high conductivity metals(e.g., Cu) reduce the induced magnetic field intensity significantly. Furthermore, transfer power, transfer efficiency, receiving efficiency, and eddy current losses all increase with the increase of the number of etched layers. These results can benefit MCET by efficient energy transfer and safe use in metal shielded equipment.

关键词： Fractal pattern,Metal-layer-shield,Eddy current,Magnetic coupling energy transfer

Designing Electronic Structures of Multiscale Helical Converters for Tailored Ultrabroad Electromagnetic Absorption

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Nano-Micro Letters 2025年第1期17卷 439-455页

作者： Zhaobo Feng Chongbo Liu Xin Li guangsheng Luo Naixin Zhai Ruizhe Hu Jing Lin Jinbin Peng Yuhui Peng Renchao che Key Laboratory of Jiangxi Province for Persistent Pollutants Control and Resources Recycle School of Environmental and Chemical EngineeringNanchang Hangkong UniversityNanchang 330063People’s Republic of China School of Physics and Materials Nanchang UniversityNanchang 330031People’s Republic of China Key Laboratory of Nondestructive Testing Ministry of EducationNanchang Hangkong UniversityNanchang 330063People’s Republic of China Laboratory of Advanced Materials Shanghai Key Lab of Molecular Catalysis and Innovative MaterialsAcademy for Engineering and TechnologyFudan UniversityShanghai 200438People’s Republic of China

Atomic-scale doping strategies and structure design play pivotal roles in tailoring the electronic structure and physicochemical property of electromagnetic wave absorption(EMWA)***,the relationship between configuration and electromagnetic(EM)loss mechanism has remained ***,drawing inspiration from the DNA transcription process,we report the successful synthesis of novel in situ Mn/N co-doped helical carbon nanotubes with ultrabroad EMWA *** calculation and EM simulation confirm that the orbital coupling and spin polarization of the Mn–N4–C configuration,along with cross polarization generated by the helical structure,endow the helical converters with enhanced EM *** a result,HMC-8 demonstrates outstanding EMWA performance,achieving a minimum reflection loss of−63.13 dB at an ultralow thickness of 1.29 *** precise tuning of the graphite domain size,HMC-7 achieves an effective absorption bandwidth(EAB)of 6.08 GHz at 2.02 mm ***,constructing macroscale gradient metamaterials enables an ultrabroadband EAB of 12.16 GHz at a thickness of only 5.00 mm,with the maximum radar cross section reduction value reaching 36.4 dB *** innovative approach not only advances the understanding of metal–nonmetal co-doping but also realizes broadband EMWA,thus contributing to the development of EMWA mechanisms and applications.

关键词： Metal-nonmetal co-doping 3d-2p orbital coupling Spin polarization Helical structure Broadband EM wave absorption

Effectiveness of a hydroxynaphthoquinone fraction from Arnebia euchroma in rats with experimental colitis

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World Journal of Gastroenterology 2013年第48期19卷 9318-9327页

作者： Hua-Ying Fan Zi-Liang Zhang Ke Liu Ming-Yan yang wei-hong Lv Xin che Hui Xu wei-wei Song School of Pharmacy Yantai University College of Life Science Jilin University Shandong Target Drug Research Co. Ltd.

AIM:To evaluate the potential effectiveness of hydroxynaphthoquinone mixture(HM)in rats with 2,4,6-trinitrobenzene sulfonic acid(TNBS)-induced ***:Colitis was induced by intracolonic administration of TNBS(80 mg/kg,dissolved in 50%ethanol).Rats were treated daily for 7 d with HM(2.5,5,10 mg/kg)and mesalazine 100 mg/kg 24 h after TNBS *** progression was monitored daily by observation of clinical signs and body weight *** the end of the experiment,macroscopic and histopathologic lesions of rats were scored,and myeloperoxidase(MPO)activity was *** also determined inflammatory cytokine tumor necrosis factor(TNF)-αlevel by ELISA,Western blotting and immunochemistry to explore the potential mechanisms of ***:After intracolonic instillation of TNBS,animals developed colitis associated with soft stool,diarrhea and marked colonic *** of HM significantly attenuated clinical and histopathologic severity of TNBS-induced colitis in a dose-dependent *** abrogated body weight loss,diarrhea and inflammation,decreased macroscopic damage score,and improved histological signs,with a significant reduction of inflammatory infiltration,ulcer size and the severity of goblet cell depletion(all P<0.05 vs TNBS alone group).HM could reduce MPO *** addition,it also decreased serum TNF-αlevel and down-regulated TNF-αexpression in colonic *** reduction was statistically significant when the dose of HM was 10 mg/kg(P<0.05 vs TNBS alone group),and the effect was comparable to that of mesalazine and showed no apparent adverse *** underlying mechanism may be associated with TNF-α***:These findings suggest that HM possesses favourable therapeutic action in TNBS-induced colitis,which provides direct pharmacological evidence for its clinical application.

关键词： Arnebia euchroma(Royle) Johnst Hydroxynaphthoquinones Inflammatory bowel disease 2,4,6-trinitrobenzene sulfonic acid-induced colitis Tumor necrosis factor