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Rare Metals 2021年第12期40卷 3494-3500页

作者： Hai-Feng Huang yi-na gui Fu Sun Zhi-Jian Liu Hui-Long Ning Chen Wu Li-Bao Chen State Key Laboratory of Powder Metallurgy Central South UniversityChangsha 410083China Institute of Bioenergy and Bioprocess Technology Chinese Academy of SciencesQingdao 266101China

The practical application of the lithium anode in lithium metal batteries(LMBs) has been hindered by the uncontrollable growth of lithium dendrite and the high volumetric change during cycling. Herein, the in situ formed three-dimensional(3D) lithium-boron(Li-B) alloy is suggested as an excellent alternative to the Li metal, in which the 3D Li B skeleton can mitigate the growth of Li dendrites and volumetric change. In this study, the Li-B alloy anodes with different B contents were manufactured by high-temperature melting. It was found that the boron content had a significant effect on the electrochemical performance of the Li-B alloy. The Li-B alloy with the least B content(10 wt%, 10LiB) demonstrated the lowest overpotential of 0.0852 V after 300 h and the lowest interface resistance. However, the full cell with 15LiB as the anode displayed the best cycling performance of 115 m Ah·g^(-1) after 100 cycles with a columbic efficiency greater than 97%. The obtained results suggest that the in situ formed three-dimensional Li-B alloy anode can be an excellent alternative to the Li anode via tuning B contents for next-generation high energy density LMBs.

关键词： Li-B alloy 3D skeleton Solid electrolyte interface(SEI) Anode Lithium metal battery

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Traffic safety helmet wear detection based on improved YOLOv5 network

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Optoelectronics Letters 2025年第1期21卷 35-42页

作者： gui Dongdong SUN Bo College of Software Southeast University Quanzhou Equipment Research Centre Haixi Institute Chinese Academy of Sciences

Aiming at the problem that the current traffic safety helmet detection model can't balance the accuracy of detection with the size of the model and the poor generalization of the model, a method based on improving you only look once version 5(YOLOv5) is proposed. By incorporating the lightweight Ghost Net module into the YOLOv5 backbone network, we effectively reduce the model size. The addition of the receptive fields block(RFB) module enhances feature extraction and improves the feature acquisition capability of the lightweight model. Subsequently, the high-performance lightweight convolution, GSConv, is integrated into the neck structure for further model size compression. Moreover, the baseline model's loss function is substituted with efficient insertion over union(EIoU), accelerating network convergence and enhancing detection precision. Experimental results corroborate the effectiveness of this improved algorithm in real-world traffic scenarios.

关键词： Traffic control

Offload Strategy for Edge Computing in Satellite Networks Based on Software Defined Network

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Computers, Materials & Continua 2025年第1期82卷 863-879页

作者： Zhiguo Liu Yuqing gui Lin Wang yingru Jiang Communication and Network Laboratory Dalian UniversityDalian116622China College of Environment and Chemical Engineering Dalian UniversityDalian116622China

Satellite edge computing has garnered significant attention from researchers;however,processing a large volume of tasks within multi-node satellite networks still poses considerable *** sharp increase in user demand for latency-sensitive tasks has inevitably led to offloading bottlenecks and insufficient computational capacity on individual satellite edge servers,making it necessary to implement effective task offloading scheduling to enhance user *** this paper,we propose a priority-based task scheduling strategy based on a Software-Defined Network(SDN)framework for satellite-terrestrial integrated networks,which clarifies the execution order of tasks based on their ***,we apply a Dueling-Double Deep Q-Network(DDQN)algorithm enhanced with prioritized experience replay to derive a computation offloading strategy,improving the experience replay mechanism within the Dueling-DDQN ***,we utilize the Deep Deterministic Policy Gradient(DDPG)algorithm to determine the optimal resource allocation strategy to reduce the processing latency of *** results demonstrate that the proposed d3-DDPG algorithm outperforms other approaches,effectively reducing task processing latency and thus improving user experience and system efficiency.

关键词： Satellite network edge computing task scheduling computing offloading

Efficient photocatalytic reduction of CO2 to formate by a molecular noble metal-free system

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Science China Chemistry 2025年第1期68卷 152-156页

作者： Lihua Zhang Lingjing Chen Huatian Shi Yue Wei gui Chen Tai-Chu Lau School of Environment and Civil Engineering Research Center for Eco-environmental Engineering Dongguan University of Technology Department of Chemistry and Institute of Molecular Functional Materials City University of Hong Kong

Reducing CO2to carbon-neutral solar fuels can not only alleviate the energy demand but also mitigate the greenhouse *** present,developing an efficient non-noble metal photo/electrocatalytic system for converting CO2to a specific product beyond CO is still a big ***,we report a new cobalt complex bearing 2,2′-bi-1,10-phenanthroline ligand that can photocatalytically reduce CO2to formate （HCOO-）.Turnover number （TON） for HCOO-up to 677 with 99%selectivity can be achieved using organic dyes purpurin as photosensitizer and 1,3-dimethyl-2-phenyl-2,3-dihydro-1H-benzo[d]imidazole （BIH） as sacrificial reductant in a CO2-saturated NMP/TEA （v/v,3:1） solution under visible light *** potential electrolysis at-1.41 V （***/Ag Cl） in the presence of 12 m M Et3NHBF4also produced HCOO-with Faradaic efficiency of 39%.Spectroscopic and electrochemical studies suggest that a[CoI-H]species is the key intermediate for CO2reduction.

关键词： photocatalysis noble metal-free CO2 reduction formate cobalt hydride

Observation of acoustic hybrid topological phases induced by the p-d orbital interactions

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 132-139页

作者： Xiao Xiang Feng Gao Yu-gui Peng Peng Wu Zong-Lin Li Xue-Feng Zhu School of Physics and Innovation Institute Huazhong University of Science and Technology

In spinless systems,growing attention has recently been attracted to synthetic gauge fields,which redefine the fundamental crystal symmetries by utilizing the projective algebraic ***,synthetic gauge fields have been commonly investigated in single orbital systems,and explorations on hybrid orbitals remain elusive in ***,we report the experimental observation of hybrid topological phases induced by hybrid synthetic gauge flux,which is formed by the interaction between p and d orbitals embedded in acoustic *** breaking the translation symmetries of Lxand/or Ly,we unambiguously demonstrate the first-order M?bius edge states and higher-order corner *** work establishes a platform for seeking exotic topological phases induced by hybrid-orbitals interactions and initializing the framework of hybrid-orbitalsrelated topological *** applications can be anticipated in scenarios such as high-quality sensing and robust wave trapping due to the stepwise energy distribution of the hybrid topological phase.

关键词： topological insulator synthetic gauge field projective symmetry corner states

Cooperative output regulation of heterogeneous directed multi-agent systems: a fully distributed model-free reinforcement learning framework

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Science China(Information Sciences) 2025年

作者： Xiongtao SHI Yanjie LI Chenglong DU Huiping LI Chaoyang CHEN Weihua gui Guangdong Key Laboratory of Intelligent Morphing Mechanisms and Adaptive Robotics School of Mechanical Engineering and Automation Harbin Institute of Technology (Shenzhen) School of Automation Central South University School of Marine Science and Technology Northwestern Polytechnical University School of Information and Electrical Engineering Hunan University of Science and Technology

In this paper, the cooperative output regulation (COR) problem of a class of unknown heterogeneous multi-agent systems (MASs) with directed graphs is studied via a model-free reinforcement learning (RL) based fully distributed eventtriggered control (ETC) strategy. First, we consider the scenario that the exosystem is accessible globally to all agents, an internal model-based augmented algebraic Riccati equation (AARE) is constructed, and its solution is learned by the proposed model-free RL algorithm via online input-output data. Further, for the scenario that the exosystem is accessible only to its adjacent followers, the distributed observers are designed for each agent to get the state of the exosystem, and an internal modelbased fully distributed adaptive ETC protocol is then synthesized to construct the corresponding AARE, and the feedback gain matrix is learned in a model-free fashion. The model-free RL-based control protocol proposed in this paper can not only remove the prior knowledge of agents’ dynamics, but also release the dependence on global information by the adaptive event-triggered mechanism (ETM) and the new graph-based Lyapunov function. Finally, simulation results are illustrated to show the feasibility and effectiveness of the proposed control scheme.

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Effect of the O2/Ar Pressure Ratio on the Microstructure and Surface Morphology of Epi-MgO/IBAD-MgO Templates for GdBa2Cu3O7？δ Coated Conductors

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Chinese Physics Letters 2014年第3期31卷 160-163页

作者： LUO Qiang LIU Lin-Fei XIAO gui-na LI yi-Jie Department of Physics and Astronomy Shanghai Jiao Tong University Shanghai 200240

High-quality epi-MgO buffer layers under different O2/Ar pressure ratios are fabricated by rf magnetron sputtering on textured IBAD-MgO templates. Under the total deposition pressure remaining constant （14 Pa）, the effect of changing the ratio of O2/Ar pressure from 1：4 to 3：2 on the microstructure and surface morphology of epi-MgO films is studied. The microstructure and morphology of epi-MgO are fully characterized by x-ray diffraction, atom force microscope and scanning electron microscope. The best texture quality of epi-MgO with an out-plane Δω value of 1.8° and an in-plane Δ？ value of 5.22° are obtained under the ratio of O2/Ar pressure 3：2. Further, the surface morphology indicates that the surface of epi-MgO is smooth with rms surface roughness about 4.7 nm at O2/Ar pressure ratio 3：2. After that, GdBa2Cu3O7？δ （GBCO） layers are deposited on the CeO2 cap layer buffered epi-MgO/IBAD-MgO templates to assess the efficiency of such a buffer layer stack. The critical current density of GBCO films （thickness of 200 nm） is higher than 3 MA/cm2, indicating that epi-MgO/IBAD-MgO is promising for depositing superconducting layers with a higher critical current density.

关键词： Magnesia

Chinese prototype building models for simulating the energy performance of the nationwide building stock

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Building Simulation 2023年第8期16卷 1559-1582页

作者： Jingjing An yi Wu Chenxi gui Da Yan School of Environment and Energy Engineering Beijing University of Civil Engineering and ArchitectureBeijingChina Building Energy Research Center School of ArchitectureTsinghua UniversityBeijingChina

Building energy modeling(BEM)has become increasingly used in building energy conservation *** building models are developed to represent the typical urban building characteristics of a specific building type,meteorological conditions,and construction *** study included four residential buildings and 11 commercial buildings to represent nationwide building types in *** consideration of five climate zones and different construction years corresponding to national standards,a total of 151 prototype building models were *** building envelope properties,occupancy and energy-related behaviors,and heating,ventilation,and air-conditioning(HVAC)system characteristics were defined according to the corresponding building energy efficiency design standards,HVAC design standards,and through other sources,such as questionnaire surveys,on-site measurements,and literature,which reflect the real situation of existing buildings in *** on the developed prototype buildings,a large database of 9225 models in 270 cities was further developed to facilitate users to simulate building energy in different *** conclusion,the developed prototype building models can represent realistic building characteristics and construction practices of the most common residential and commercial buildings in China,serving as an important foundation for *** models can be used for analyses related to building energy conservation research on typical individual buildings,including energy-saving technologies,advanced controls,and new policies,and providing a reference for the development of building energy codes and standards.

关键词： prototype building models building stock modeling Chinese building building performance simulation energy conservation

Population dynamics and protection strategies of Litsea coreana *** with guizhou Province in China as an example

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Journal of Mountain Science 2023年第4期20卷 1090-1101页

作者： YUAN Gang-yi GUO Qi-qiang XIE na ZHANG Ya-qin LUO Si-qiong gui Qin YAO Shan Institute for Forest Resources and Environment of guizhou College of ForestryGuizhou UniversityGuiyang550025China

Studying the dynamics of plant populations is crucial to the conservation and management of endangered *** diameter at breast height(DBH),tree height,crown width,and environmental factors of a total of 15 plots in five populations in guizhou Province,China were measured in this *** method of substituting diameter at breast height for age was used to divide the population into 7 age *** age structure,static life table,and relationship between the population characteristics and environmental factors of the Litsea coreana *** population were ***,the time series model was used to predict the population *** showed that the age structure of population in Zhengan County(Population ZA)had an inverted Jshape with abundant seedlings and insufficient middle-aged and elderly *** age structures of populations in Daozhen County(Population DZ),Kaiyang County(KY),Meitan County(Population MT),and Xishui County(Population XS)were spindle-shaped with few young individuals and many middle-aged and elderly *** mortality rate of each population fluctuated with the increase in age class,and the populations were extremely *** survival curve was close to the Deevey III type,and the degree of deviation was related to the lack of young *** the age stages II,IV,and VI,the number of aged plants in the different populations initially increased then decreased,and population stability was difficult to *** analysis showed that the DBH,tree height and crown width of the population decreased with the increase of annual mean temperature,and the population density was restricted by soil nutrient conditions to a certain *** results of this work provide scientific basis for the conservation and sustainable utilization of natural populations of *** *** in guizhou Province,China.

关键词： Litsea coreana var.sinensis Age structure Survival curve Time series prediction Environmental factor

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Activation of Carbon Dioxide by Gas-phase Metal Species

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Chinese Journal of Structural Chemistry 2021年第10期40卷 1385-1403页

作者： LIU Yun-Zhu LI Xiao-na HE Sheng-gui State Key Laboratory for Structural Chemistty of Unstable and Stable Species Institute of ChemistryChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China Beijing national Laboratory for Molecular Sciences and CAS Research/Educatiou Center of Excellence in Molecular Sciences Beijing 100190China

Catalytic conversion of carbon dioxide(CO_(2)) into value-added chemicals is an important and active field in both of the condensed-phase and gas-phase studies. This mini-review summarizes a variety of experimentally identified reactions in the activation and transformation of CO_(2) by metal species in the gas phase. The use of advanced mass spectrometric instrumentation in conjunction with quantum chemistry calculations can uncover the mechanistic details and determine the vital factors that control the activation of CO_(2). This review focuses mainly on three topics: the activation of CO_(2) by(1) bare metal ions and metal oxide species,(2) metal hydrides, and(3) other gas-phase metal species. Emphasis is placed on the latest advances in the hydrogenation of CO_(2) mediated with metal hydrides. A potential prospect toward the future effort in the activation and transformation of CO_(2) in gas phase has also been discussed.

关键词： carbon dioxide activation gas-phase metal species mass spectrometry quantum chemistry calculations

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