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National Science Review 2020年第8期7卷 1360-1366页

作者： Xuan Zhao Yu Wang yunli da Xinxia Wang Tingting Wang Mingquan Xu Xiaoyun He Wu Zhou Yafei Li Jonathan N.Coleman Yanguang Li Institute of Functional Nano and Soft Materials (FUNSOM) Jiangsu Key Laboratory for Carbon-Based Functional Materials and Devices Soochow University College of Chemistry and Materials Science Nanjing Normal University College of Material Science and Opto-Electronic Technology University of Chinese Academy of Sciences School of Physical Sciences and CAS Key Laboratory of Vacuum Sciences University of Chinese Academy of Sciences School of Physics CRANN and AMBER Centers Trinity College Dublin

The two-electron reduction of molecular oxygen represents an effective strategy to enable the green, mild and on-demand synthesis of hydrogen peroxide. Its practical viability, however, hinges on the development of advanced electrocatalysts, preferably composed of non-precious elements, to selectively expedite this reaction, particularly in acidic medium. Our study here introduces 2H-MoTe;for the first time as the efficient non-precious-metal-based electrocatalyst for the electrochemical production of hydrogen peroxide in acids. We show that exfoliated 2H-MoTe;nanoflakes have high activity(onset overpotential ～140 mV and large mass activity of 27 A g;at 0.4 V versus reversible hydrogen electrode), great selectivity（H;O;percentage up to 93%） and decent stability in 0.5 M H;SO;. Theoretical simulations evidence that the high activity and selectivity of 2H-MoTe;arise from the proper binding energies of HOO;and O;at its zigzag edges that jointly favor the two-electron reduction instead of the four-electron reduction of molecular oxygen.

关键词： hydrogen peroxide production non-precious-metal-based electrocatalyst molybdenum telluride liquid phase exfoliation zigzag edges

Controlled fabrication of freestanding monolayer SiC by electron irradiation

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Chinese Physics B 2024年第8期33卷 31-37页

作者：笪蕴力罗瑞春雷宝季威周武 School of Physical Sciences University of Chinese Academy of SciencesBeijing 100049China Department of Physics and Beijing Key Laboratory of Optoelectronic Functional Materials&Micro-Nano Devices Renmin University of ChinaBeijing 100872China

The design and preparation of novel quantum materials with atomic precision are crucial for exploring new physics and for device *** irradiation has been demonstrated as an effective method for preparing novel quantum materials and quantum structures that could be challenging to obtain *** features the advantages of precise control over the patterning of such new materials and their integration with other materials with different ***,we present a new strategy for fabricating freestanding monolayer SiC within nanopores of a graphene *** regulating the energy of the incident electron beam and the in-situ heating temperature in a scanning transmission electron microscope(STEM),we can effectively control the patterning of nanopores and subsequent growth of monolayer SiC within the graphene *** resultant SiC monolayers seamlessly connect with the graphene lattice,forming a planar structure distinct by a wide direct *** in-situ STEM observations further uncover that the growth of monolayer SiC within the graphene nanopore is driven by a combination of bond rotation and atom extrusion,providing new insights into the atom-by-atom self-assembly of freestanding two-dimensional(2D)monolayers.

关键词： monolayer SiC 2D semiconductor in-situ growth in-situ STEM defect engineering graphene nanopores

An Evolved Human-specific Epigenetic Mechanism for Cortical Expansion and Gyrification

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Neuroscience Bulletin 2021年第9期37卷 1370-1372页

作者： dan Li yunli Xie Department of Anesthesia The State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain ScienceInstitutes of Brain Scienceand Zhongshan HospitalFudan UniversityShanghai 200032China

Over evolution,the human species has acquired higher cognitive function,which helps to distinguish Homo sapiens from other ***,humans have a large neocortex through the evolutionary expansion of the brain,which is believed to be instrumental in the establishment of comprehensive neuronal circuits[1,2].A hallmark of the human brain is the highly convoluted brain surface structure,named gyrification or cortical folding,consisting of gyri and sulci,which significantly increase the cortical surface ***,the mechanisms underlying the cortical expansion remain elusive.

关键词： cortex expansion folding

Design of Luenberger function observer with disturbance decoupling for matrix second-order linear systems-a parametric approach

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Journal of Systems Engineering and Electronics 2006年第1期17卷 156-162页

作者： Wu yunli Duan Guangren Center for Control Theory and Guidance Technology Harbin Inst. of Technology Harbin 150001 P. R. China

A simple method for disturbance decoupling for matrix second-order linear systems is proposed directly in matrix second-order framework via Luenberger function observers based on complete parametric eigenstructure assignment. By introducing the H2 norm of the transfer function from disturbance to estimation error, sufficient and necessary conditions for disturbance decoupling in matrix second-order linear systems are established and are arranged into constraints on the design parameters via Luenberger function observers in terms of the closed-loop eigenvalues and the group of design parameters provided by the eigenstructure assignment approach. Therefore, the disturbance decoupling problem is converted into an eigenstructure assignment problem with extra parameter constraints. A simple example is investigated to show the effect and simplicity of the approach.

关键词： matrix second-order linear systems Luenberger function observers eigenstructure assignment disturbance decoupling

Deep sea pollen record during 12-1.6 Ma from the southern South China Sea and its response to environmental change

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Chinese Science Bulletin 2007年第15期52卷 2115-2122页

作者： LUO yunli SUN XiangJun Institute of Botany Chinese Academy of Sciences Beijing 100093 China Key Laboratory of Marine Geology Ministry of Education Tongji University Shanghai 200092 China

Based on deep-sea pollen results (512-76 m) from ODP Site 1143 in the southern South China Sea (SCS),the climate and vegetation evolution sequence on the surrounding islands and the exposed continental shelf are discussed. The pollen records show that the pollen influx was quite low before 8.15 Ma and increased dramatically afterwards. The influx changes can be ascribed,on one side,to tectonics deformations around the southern SCS resulting in rapid uplift of islands and subsequent increase of the sediment rates and pollen influx and on the other side to climate cooling and monsoon enhancement. Around 2.63 Ma was another obvious boundary,the increasing of pollen and spores influx since this time was mainly related to global climate cooling. Spectrum analysis of pollen influx values shows that 2 Ma,0.67 Ma,and 0.19-0.17 Ma cycles existed during 12-3.0 Ma,while 0.1 Ma and 46.9 ka cycles existed during 3.0-2.0 Ma.

关键词：中国南海植被进化花粉传播季风

High-throughput screening of critical size of grain growth in gradient structured nickel

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Journal of Materials Science & Technology 2021年第23期82卷 33-39页

作者： yunli Lu Fenghui Duan Jie Pan Yi Li Shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of SciencesShenyang110016China School of Materials Science and Engineering University of Science and Technology of ChinaHefei230026China

Nanocrystalline metals with high Gibbs free energy have a strong tendency towards thermally driven grain growth,thus understanding the critical size or temperature of grain growth is vital for their *** investigations of thermal stability were usually conducted on the materials with a homogeneous structure;however,these methods are time-consuming and *** the present work,we reveal a high-throughput experimental strategy to characterize the size-dependent thermal stability via annealing the gradient structured *** this method,the critical size of grain growth(d_(c))at a given annealing temperature was rapidly *** critical size of grain growth was~95 nm when annealed at 503 K for 3 h,which is consistent with the value reported in the homogeneous structured ***,this critical size was found to be identical in three types of gradient structured Ni,i.e.,independent on the gradient *** present work demonstrates a high-throughput strategy for exploring the critical size of grain growth and size-dependent thermal stability of metals.

关键词： High-throughput Gradient structure Critical size Grain growth Thermal stablitiy

Track-before-detect for Infrared Maneuvering Dim Multi-target via MM-PHD

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Chinese Journal of Aeronautics 2012年第2期25卷 252-261页

作者： LONG yunli XU Hui AN Wei LIU Li College of Electronic Science and Engineering National University of Defense TechnologyChangsha 410073China

In this paper, we present a novel and efficient track-before-detect （TBD） algorithm based on multiple-model probability hypothesis density （MM-PHD） for tracking infrared maneuvering dim multi-target. Firstly, the standard sequential Monte Carlo probability hypothesis density （SMC-PHD） TBD-based algorithm is introduced and sequentially improved by the adaptive process noise and the importance re-sampling on particle likelihood, which result in the improvement in the algorithm robustness and convergence speed. Secondly, backward recursion of SMC-PHD is derived in order to ameliorate the tracking performance especially at the time of the multi-target arising. Finally, SMC-PHD is extended with multiple-model to track maneuvering dim multi-target. Extensive experiments have proved the efficiency of the presented algorithm in tracking infrared maneuvering dim multi-target, which produces better performance in track detection and tracking than other TBD-based algorithms including SMC-PHD, multiple-model particle filter （MM-PF）, histogram probability multi-hypothesis tracking （H-PMHT） and Viterbi-like.

关键词： target tracking probability hypothesis density Monte Carlo track-before-detect importance re-sampling

A Novel Framework for IP DiffServ over Optical Burst Switching Networks

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Journal of Computer Science & Technology 2004年第6期19卷 948-954页

作者： Ke-PingLong yunli RodneyS.Tucker Chong-GangWang SpecialResearchCentreforOpticalInternetandWirelessInformationNetworks（COIWIN）SchoolofCommunicationandInformationEngineering ChongqingUniversityofPostsandTelecommunications（CQUPT）Chongqing400065P.R.China ARCSpecialResearchCentreforUltraBroadbandInformationNetworks（CUBIN） DepartmentofElectricalandElectronicEngineeringUniversityofMelbourneVictoria3010Australia HongKongUniversityofScienceandTechnology HongKongSpecialAdministrativeRegion2010P.R.China

This paper presents a novel framework for IP Differentiated Services (DiffServ) over optical burst switching (OBS), namely, DS-OBS. The network architecture, functional model of edge nodes and core nodes, the control packet format, a novel burst assembly scheme at ingress nodes and scheduling algorithm of core nodes are presented. The basic idea is to apply DiffServ capable burst assembly at ingress nodes and perform different per hop behavior (PHB) electronic treatments for control packets of different QoS class services at core nodes. Simulation results show that the proposed schemes can provide the best differentiated service for expedited forwarding (EF), assured forwarding (AF) and best effort (BE) services in terms of end-to-end delay, throughput and IP packet loss probability. Keywords IP quality of service - differentiated service - per hop behavior - optical burst switching NoteThis work is supported by the National Natural Science Foundation of China (Grant No.90304004), the National Hi-Tech Development 863 Program of China (Grant No.2003AA121540), and the research grants by the Ministry of Education of China (Grant No.204125), the Chongqing Education Commission (Grant No.050309) and the Chongqing Science Commission.

关键词： IP quality of service differentiated service per hop behavior optical burst switching

An anisotropic micromechamcal model for calculation of effective elastic moduli of Ni-based single crystal superalloys

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Science China(Technological Sciences) 2017年第3期60卷 452-458页

作者： LI ShuangYu WU WenPing LI yunli CHEN MingXiang Department of Engineering Mechanics School of Civil Engineering Wuhan University Wuhan 430072 China State Key Laboratory of Water Resources & Hydropower Engineering Science Wuhan University Wuhan 430072 China

An anisotropic micromechanical model based on Mori-Tanaka method is developed to calculate the effective elastic moduli of

关键词： Ni-based single crystal superalloys effective elastic moduli Mori-Tanaka method anisotropic inclusion

Observer design for matrix second order linear systems with uncertain disturbance input-a parametric approach

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Journal of Systems Engineering and Electronics 2006年第4期17卷 811-816,823页

作者： Wu yunli Li Zhibin Duan Cruangren National Laboratory of Space Intelligent Control Technology Beijing Inst. of Control Engineering Beijing 100080P.R.China Centre of Control Theory and Guidance Technology Harbin Inst. of Technology Harbin 150001P.R.China

A simple parametric approach to design a full-order observer for matrix second-order linear systems with uncertain disturbance input in the matrixsecond-order framework is proposed. The basic idea is to minimize the H2 norm of the transfer function from disturbance to estimation error using the design degrees of freedom provided by a parametric approach in the observer design. Besides the design parameters, the eigenvalues of the closed-loop system are also optimized within desired regions on the left-half of the complex plane. Using the proposed approach, additional specifications can be easily achieved. A spring-mass system is using to show the effect of the proposed approaches.

关键词： linear systems uncertain disturbance input observers parametric approach optimization.