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Chinese Journal of Chemistry 2024年第2期42卷 151-156页

作者： Ming Yang Xin-yu wang Jie wang yu-Long Zhao Jilin Province Key Laboratory of Organic Functional Molecular Design&Synthesis Faculty of ChemistryNortheast Normal UniversityChangchunJilin 130024China

A photocatalytic[3+2]annulation of alkenes with vinyl azides was developed under irradiation by visible light in the presence of organic dye *** substrate scope and high functional group tolerance were demonstrated by more than 50 *** reaction provides a novel and efficient method for the synthesis of polyfunctionalized pyrroles under very mild metal-free conditions without other additives.

关键词： Photocatalysis Vinyl azides Alkenes Pyrroles Annulation Radical reactions

Insights on advanced substrates for controllable fabrication of photoanodes toward efficient and stable photoelectrochemical water splitting

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Carbon Energy 2024年第4期6卷 164-221页

作者： Huilin Hou Gang shao Yang wang Wai‐Yeung Wong Weiyou Yang Institute of Micro/Nano Materials and Devices Ningbo University of TechnologyNingboChina School of Materials Science and Engineering Zhengzhou UniversityZhengzhouChina Department of Applied Biology and Chemical Technology and Research Institute for Smart Energy The Hong Kong Polytechnic UniversityHong KongChina

Conversion of solar energy into H_(2) by photoelectrochemical(PEC)water splitting is recognized as an ideal way to address the growing energy crisis and environmental *** a typical PEC cell,the construction of photoanodes is crucial to guarantee the high efficiency and stability of PEC reactions,which fundamentally rely on rationally designed semiconductors(as the active materials)and substrates(as the current collectors).In this review work,we start with a brief introduction of the roles of substrates in the PEC ***,we provide a systematic overview of representative strategies for the controlled fabrication of photoanodes on rationally designed substrates,including conductive glass,metal,sapphire,silicon,silicon carbide,and flexible ***,some prospects concerning the challenges and research directions in this area are proposed.

关键词： hydrogen photoanode photoelectrochemical substrates water splitting

Optimal decision-making method for equipment maintenance to enhance the resilience of power digital twin system under extreme disaster

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Global Energy Interconnection 2024年第3期7卷 336-346页

作者： Song Gao Wei wang Jingyi Chen Xinyu Wu Junyan shao Electric Power Scientific Research Institute State Grid Jilin Electric Power CoLtdChangchun132000P.R.China Department of Electrical Engineering Northeast Electric Power UniversityJilin132012P.R.China

Digital twins and the physical assets of electric power systems face the potential risk of data loss and monitoring failures owing to catastrophic events,causing surveillance and energy *** study aims to refine maintenance strategies for the monitoring of an electric power digital twin system post ***,the research delineates the physical electric power system along with its digital counterpart and post-disaster restoration ***,it delves into communication and data processing mechanisms,specifically focusing on central data processing(CDP),communication routers(CRs),and phasor measurement units(PMUs),to re-establish an equipment recovery model based on these data transmission ***,it introduces a mathematical optimization model designed to enhance the digital twin system’s post-disaster monitoring efficacy by employing the branch-and-bound method for its *** efficacy of the proposed model was corroborated by analyzing an IEEE-14 *** findings suggest that the proposed branch-and-bound algorithm significantly augments the observational capabilities of a power system with limited resources,thereby bolstering its stability and emergency response mechanisms.

关键词： Phasor measurement units Through-sequence optimization Resilience enhancement Communication networks Digital twins

Patterns and drivers of seasonal water sources for artificial sand-fixing plants in the northeastern Mu Us sandy land,Northwest China

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Pedosphere 2024年第1期34卷 63-77页

作者： Yanwu PEI Laiming HUANG Ming'an shao Jiao wang Yinglong ZHANG Yellow River Delta Modern Agricultural Engineering Laboratory Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China College of Natural Resources and Environment Northwest Agriculture and Forestry UniversityYangling 712100China State Key Laboratory of Urban and Regional Ecology Research Center for Eco-Environmental Sciences of Chinese Academy of SciencesBeijing 100085China College of Resources and Environment University of Chinese Academy of SciencesBeijing 100049China Shenmu Ecological Association Shenmu 719399China

Understanding plant water-use patterns is important for improving water-use efficiency and for sustainable vegetation restoration in arid and semi-arid regions. However, seasonal variations in water sources and their control by different sand-fixing plants in water-limited desert ecosystems remain poorly understood. In this study, stable isotopic ratios of hydrogen(δ^(2)H) and oxygen(δ^(18)O) in precipitation, soil water, groundwater, and xylem water were determined to document seasonal changes in water uptake by three representative plant species(Pinus sylvestris var. mongolica Litv., Amygdalus pedunculata Pall., and Salix psammophila) in the northeastern Mu Us sandy land, Northwest China. Based on the depth distribution and temporal variation of measured gravimetric soil water content(SWC), the soil water profile of the three species stands was divided into active(0.01 g g^(-1)45%) layers. Annually, P. sylvestris, A. pedunculata, and S. psammophila obtained most water from deep(59.2%±9.7%, moist layer and groundwater),intermediate(57.4%±9.8%, stable and moist layers), and shallow(54.4%±10.5%, active and stable layers) sources, respectively. Seasonally, the three plant species absorbed more than 60% of their total water uptake from the moist layer and groundwater in the early(June) dry season;then, they switched to the active and stable layers in the rainy season(July–September) for water resources(50.1%–62.5%). In the late(October–November) dry season, P. sylvestris(54.5%–66.2%) and A. pedunculata(52.9%–63.6%) mainly used water from stable and moist layers, whereas S. psammophila(52.6%–70.7%) still extracted water predominantly from active and stable layers. Variations in the soil water profile induced by seasonal fluctuations in precipitation and groundwater levels and discrepancies in plant pheno

关键词： desert ecosystem MixSIAR model plant water uptake soil moisture stable isotopes vegetation restoration water-use efficiency

Genesis and Accumulation of Paleo-Oil Reservoir in Dabei Area,Kuqa Depression,Northwest China:Implications for Tight-Gas Accumulation

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Journal of Earth Science 2024年第2期35卷 655-665页

作者： Fujie Jiang Xiao Chen Pengwei wang Xinghe shao Haijun Yang State Energy Center for Shale Oil Research and Development Beijing102206China National Key Laboratory of Oil and Gas Resources and Engineering Beijing102249China College of Geosciences China University of PetroleumBeijing102249China CNOOC International Ltd. Beijing100027China Research Institute of Petroleum Exploration&Production SINOPECBeijing100083China Research Institute of Petroleum Exploration and Development Tarim OilfieldPetroChinaKorla841000China

Paleo-oil reservoir is of great importance to understand hydrocarbon enrichment mechanism and hydrocarbon exploration potential,but is yet poorly investigated in Kuqa *** occurrence of the paleo-oil reservoir in Dabei area was proved by quantitative grain fluorescence(QGF)and fluid inclusion *** history of the paleo-oil reservoir was reconstructed through:(1)oil-source correlation;(2)time coupling of source rock maturation,porosity evolution and migration *** impact of paleo-oil reservoir on tight-gas accumulation was consequently *** suggest that considerable oil was accumulated in the K_(1)bs reservoir with paleo oil-water contact in Dabei 2 Well and Dabei 201 Well at 5800 and 6040 m,*** oil was primarily sourced from Triassic source rocks with Jurassic source rocks of secondary importance,which was at oil generation window(0.7%–1.1%Ro)during 9–6 and 7.5–5 Ma,*** occurrence of K_(1)bs tight reservoir(porosity<12%)was about 25 Ma,while faults and associated fractures at Kelasue structural belt were developed approximately from 8 to 3.5 ***,the tight oil accumulation was formed during 8–5 *** paleo-oil reservoir in Dabei 1 gas field was destroyed by the evaporation fractionation in later stage.

关键词： Paleo-oil reservoir Dabei area Kuqa Depression Northwest China petroleum geology

Atomically Dispersed Zinc Active Sites Efficiently Promote the Electrochemical Conversion of N2 to NH3

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Energy & Environmental Materials 2024年第03期7卷 179-185页

作者： Yanjiao Wei Xinyu wang Mengjie Sun Min Ma Jian Tian Minhua shao School of Materials Science and Engineering Shandong University of Science and Technology Department of Chemical and Biological Engineering The Hong Kong University of Science and Technology Energy Institute and Chinese National Engineering Research Center for Control & Treatment of Heavy Metal PollutionThe Hong Kong University of Science and Technology

At present,the research on highly active and stable nitrogen reduction reaction catalysts is still challenging work for the electrosynthesis of ammonia （NH3）.Herein,we synthesized atomically dispersed zinc active sites supported on N-doped carbon nanosheets （Zn/NC NSs） as an efficient nitrogen reduction reaction catalyst,which achieves a high ammonia yield of46.62μ***-0.85 V （vs RHE） and Faradaic efficiency of 95.8%at-0.70 V （vs RHE）.In addition,Zn/NC NSs present great stability and selectivity,and there is no significant change in NH3rate and Faradaic efficiencies after multiple *** structural characterization shows that the active center in the nitrogen reduction reaction process is the Zn-N4sites in the *** calculation confirms that Zn/NC with Zn-N4configuration has a lower energy barrier for the formation of*NNH intermediate compared with pure N-doped carbon nanosheets （N-C NSs）,thus promoting the hydrogenation kinetics in the whole nitrogen reduction reaction process.

关键词： electrocatalysis nitrogen reduction single-atom catalyst Zn–N4

Adaptive Trajectory Tracking Control for Nonholonomic Wheeled Mobile Robots:A Barrier Function Sliding Mode Approach

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IEEE/CAA Journal of Automatica Sinica 2024年第4期11卷 1007-1021页

作者： yunjun Zheng Jinchuan Zheng Ke shao Han Zhao Hao Xie Hai wang the School of Mechanical Engineering Hefei University of TechnologyHefei 230009China the School of Science Computing and Engineering TechnologiesSwinburne University of TechnologyHawthorn VIC 3122Australia the School of Civil Aviation Northwestern Polytechnical UniversityXi’an 710072China the Shanghai Aerospace Control Technology Institute Shanghai 201109 the School of Automation Science and Electrical Engineering Beihang UniversityBeijing 100191China the College of Science HealthEngineering and EducationMurdoch UniversityPerth WA6150Australia

The trajectory tracking control performance of nonholonomic wheeled mobile robots(NWMRs)is subject to nonholonomic constraints,system uncertainties,and external *** paper proposes a barrier function-based adaptive sliding mode control(BFASMC)method to provide high-precision,fast-response performance and robustness for *** with the conventional adaptive sliding mode control,the proposed control strategy can guarantee that the sliding mode variables converge to a predefined neighborhood of origin with a predefined reaching time independent of the prior knowledge of the uncertainties and disturbances *** advantage of the proposed algorithm is that the control gains can be adaptively adjusted to follow the disturbances amplitudes thanks to the barrier *** benefit is that the overestimation of control gain can be eliminated,resulting in chattering ***,a modified barrier function-like control gain is employed to prevent the input saturation problem due to the physical limit of the *** stability analysis and comparative experiments demonstrate that the proposed BFASMC can ensure the prespecified convergence performance of the NWMR system output variables and strong robustness against uncertainties/disturbances.

关键词： Adaptive sliding mode barrier function nonholonomic wheeled mobile robot(NWMR) trajectory tracking control

A Survey on an Emerging Safety Challenge for Autonomous Vehicles:Safety of the Intended Functionality

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Engineering 2024年第2期33卷 17-34页

作者： Hong wang Wenbo shao Chen Sun Kai Yang Dongpu Cao Jun Li Tsinghua Intelligent Vehicle Design and Safety Research Institute School of Vehicle and MobilityTsinghua UniversityBeijing 100084China CogDrive Lab Department of Mechanical and Mechatronics EngineeringUniversity of WaterlooWaterlooON N2L3G1Canada College of Mechanical and Vehicle Engineering Chongqing UniversityChongqing 400044China

As the complexity of autonomous vehicles(AVs)continues to increase and artificial intelligence algorithms are becoming increasingly ubiquitous,a novel safety concern known as the safety of the intended functionality(SOTIF)has emerged,presenting significant challenges to the widespread deployment of *** focuses on issues arising from the functional insufficiencies of the AVs’intended functionality or its implementation,apart from conventional safety *** the systems engineering standpoint,this study offers a comprehensive exploration of the SOTIF landscape by reviewing academic research,practical activities,challenges,and perspectives across the development,verification,validation,and operation *** research encompasses system-level SOTIF studies and algorithm-related SOTIF issues and ***,it encapsulates practical SOTIF activities undertaken by corporations,government entities,and academic institutions spanning international and Chinese contexts,focusing on the overarching methodologies and practices in different ***,the paper presents future challenges and outlook pertaining to the development,verification,validation,and operation phases,motivating stakeholders to address the remaining obstacles and challenges.

关键词： Safety of the intended functionality Autonomous vehicles Artificial intelligence Uncertainty Verification Validation

A Comparison of Four Neural Networks Algorithms on Locomotion Intention Recognition of Lower Limb Exoskeleton Based on Multi-source Information

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Journal of Bionic Engineering 2024年第1期21卷 224-235页

作者： Duojin wang Xiaoping Gu Hongliu yu Institute of Rehabilitation Engineering and Technology University of Shanghai for Science and Technology516 Jungong RoadShanghai 200093China Shanghai Engineering Research Center of Assistive Devices 516 Jungong RoadShanghai 200093China

Lower Limb Exoskeletons(LLEs)are receiving increasing attention for supporting activities of daily *** such active systems,an intelligent controller may be *** this paper,we proposed a locomotion intention recognition system based on time series data sets derived from human motion *** of input data and Deep Learning(DL)algorithms,this framework enables the detection and prediction of users’movement *** makes it possible to predict the detection of locomotion modes,allowing the LLEs to provide smooth and seamless *** pre-processed eight subjects were used as input to classify four scenes:Standing/Walking on Level Ground(S/WOLG),Up the Stairs(US),Down the Stairs(DS),and Walking on Grass(WOG).The result showed that the ResNet performed optimally compared to four algorithms(CNN,CNN-LSTM,ResNet,and ResNet-Att)with an approximate evaluation indicator of 100%.It is expected that the proposed locomotion intention system will significantly improve the safety and the effectiveness of LLE due to its high accuracy and predictive performance.

关键词： Lower limb exoskeletons(LLEs) Locomotion intention ResNet Multi-source

BLS-identification:A device fingerprint classification mechanism based on broad learning for Internet of Things

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Digital Communications and Networks 2024年第3期10卷 728-739页

作者： yu Zhang Bei Gong Qian wang Faculty of Information Technology Beijing University of TechnologyBeijing100124China School of Information Science and Technology Zhengzhou Normal UniversityHenan450044China

The popularity of the Internet of Things(IoT)has enabled a large number of vulnerable devices to connect to the Internet,bringing huge security *** a network-level security authentication method,device fingerprint based on machine learning has attracted considerable attention because it can detect vulnerable devices in complex and heterogeneous access ***,flexible and diversified IoT devices with limited resources increase dif-ficulty of the device fingerprint authentication method executed in IoT,because it needs to retrain the model network to deal with incremental features or *** address this problem,a device fingerprinting mechanism based on a Broad Learning System(BLS)is proposed in this *** mechanism firstly characterizes IoT devices by traffic analysis based on the identifiable differences of the traffic data of IoT devices,and extracts feature parameters of the traffic packets.A hierarchical hybrid sampling method is designed at the preprocessing phase to improve the imbalanced data distribution and reconstruct the fingerprint *** complexity of the dataset is reduced using Principal Component Analysis(PCA)and the device type is identified by training weights using *** experimental results show that the proposed method can achieve state-of-the-art accuracy and spend less training time than other existing methods.

关键词： Device fingerprint Traffic analysis Class imbalance Broad learning system Access authentication