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Journal of Energy Chemistry 2025年第01期 760-769页

作者： lin peng Yu Bai Hang Li Meixiu Qu Zhenhua Wang Kening Sun Advanced Research Institute of Multidisciplinary Science Beijing Institute of Technology Beijing Key Laboratory of Chemical Power Source and Green Catalysis School of Chemistry and Chemical Engineering Beijing Institute of Technology

Lithium-sulfur （Li-S） batteries have gained great attention due to the high theoretical energy density and low cost,yet their further commercialization has been obstructed by the notorious shuttle effect and sluggish redox ***,we supply a strategy to optimize the electron structure of Ni2P by concurrently introducing B-doped atoms and P vacancies in Ni2P （Vp-B-Ni2P）,thereby enhancing the bidirectional sulfur *** study indicates that the simultaneous introduction of B-doped atoms and P vacancies in Ni2P causes the redistribution of electron around Ni atoms,bringing about the upward shift of d-band center of Ni atoms and effective d-p orbital hybridization between Ni atoms and sulfur species,thus strengthening the chemical anchoring for lithium polysulfides （LiPSs） as well as expediting the bidirectional conversion kinetics of sulfur ***,theoretical calculations reveal that the incorporation of B-doped atoms and P vacancies in Ni2P selectively promotes Li2S dissolution and nucleation ***,the Li-S batteries with Vp-B-Ni2P-separators present outstanding rate ability of 777 m A h g-1at 5 C and high areal capacity of 8.03 mA h cm-2under E/S of 5μL mg-1and sulfur loading of 7.20 mg *** work elucidates that introducing heteroatom and vacancy in metal phosphide collaboratively regulates the electron structure to accelerate bidirectional sulfur conversion.

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Distributed gradient-based sampling algorithm for least-squares in switching multi-agent networks

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Science China(Information Sciences) 2020年第9期63卷 284-293页

作者： peng lin Hongsheng QI Key Laboratory of Systems and Control Academy of Mathematics and Systems ScienceChinese Academy of Sciences School of Mathematical Sciences University of Chinese Academy of Sciences

Dear editor,Recent years have witnessed a rapid growth of distributed design in multi-agent networks because of the scalability, robustness and low cost. Compared with the conventional centralized and parallel design, all agents in fully distributed design aim to achieve the global goal only based on the local measurement and information sharing with

关键词： multi-agent systems distributed algorithms least-squares gradient-based sampling time-varying networks

Distributed regression estimation with incomplete data in multi-agent networks

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Science China(Information Sciences) 2018年第9期61卷 168-181页

作者： Yinghui WANG peng lin Yiguang HONG University of Chinese Academy of Sciences Key Laboratory of Systems and Control Academy of Mathematics and Systems ScienceChinese Academy of Sciences

In this paper, distributed regression estimation problem with incomplete data in a time-varying multi-agent network is investigated. Regression estimation is carried out based on local agent information with incomplete in the non-ignorable mechanism. By virtue of gradient-based design and adaptive filter, a distributed algorithm is proposed to deal with a regression estimation problem with incomplete data. With the help of convex analysis and stochastic approximation techniques, the exact convergence is obtained for the proposed algorithm with incomplete data and a jointly-connected multi-agent topology. Moreover, online regret analysis is also given for real-time learning. Then, simulations for the proposed algorithm are also given to demonstrate how it can solve the estimation problem in a distributed way, even when the network configuration is time-varying.

关键词： multi-agent systems time-varying network estimation with incomplete data online learning stochastic approximation

A high-order model of rotating stall in axial compressors with inlet distortion

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Chinese Journal of Aeronautics 2017年第3期30卷 898-906页

作者： peng lin Cong WANG Yong WANG School of Automation Science and Engineering South China University of Technology Department of Mechanics and Engineering Science Peking University

In this paper,a high-order distortion model is proposed for analyzing the rotating stall inception process induced by inlet distortion in axial compressors.A distortion-generating screen in the compressor inlet is *** assuming a quadratic function for the local flow total pressure-drop,the existing Mansoux model is extended to include the effects of static inlet distortion,and a new high-order distortion model is *** illustrate the effectiveness of the distortion model,numerical simulations are performed on an eighteenth-order *** is demonstrated that long length-scale disturbances emerge out of the distorted background flow,and further induce the onset of rotating stall in *** addition,the circumferential non-uniform distribution and time evolution of the axial flow are also shown to be consistent with the existing *** is thus shown that the high-order distortion model is capable of describing the transient behavior of stall inception and will contribute further to stall detection under inlet distortion.

关键词： Axial compressors Dynamic modeling Flow instability Inlet distortion Rotating stall Stall inception

NUMERICAL SIMULATION OF PROPAGATION AND BREAKING PROCESSES OF A FOCUSED WAVES GROUP

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Journal of Hydrodynamics 2012年第3期24卷 399-409页

作者： HUANG Zong-liu lin peng-zhi State Key Laboratory of Hydraulics and Mountain River Engineering Sichuan University Chengdu 610065China

A two-dimensional numerical wave flume is developed to study the focused waves group propagation and the consequent breaking processes. The numerical model is based on the Reynolds-Averaged Navier-Stokes （PANS） equations, with the standard k - c turbulence model to simulate the turbulence effects. To track the complicated and broken free-surface, the Volume Of Fluid （VOF） method is employed. The numerical model combines the ＂Partial Cell Treatment （PCT）＂ method with the ＂Locally Relative Stationary （LRS）＂ concept to treat the moving wave paddle so that various waves can be generated directly in a fixed Cartesian grid system. The theoretical results of the linear and nonlinear waves are used to validate the numerical wave flume firstly, and then a plunging breaking wave created by a focused waves group is simulated. The numerical results are compared to the experimental data and other simulation results, with very good agreements. The turbulence intensity, the flow field and the energy dissipation in the breaking processes are analyzed based on the numerical results. It is shown that the present numerical model is efficient and accurate for studying the waves group generation, the waves packet propagation, and the wave breaking processes.

关键词： focused waves group plunging breaking Volume Of Fluid (VOF) k - ε turbulence model irregular wave maker

Depth-resolved numerical model of dam break mud flows with Herschel-Bulkley rheology

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Journal of Mountain Science 2022年第4期19卷 1001-1017页

作者： TANG Jin-bo lin peng-zhi CUI peng State Key Laboratory of Hydraulics and Mountain River Engineering Sichuan UniversityChengdu 610065China Key Laboratory of Mountain Hazards and Earth Surface Processes Chinese Academy of SciencesInstitute of Mountain Hazards and EnvironmentChinese Academy of Sciences and Ministry of Water ConservancyChengdu 610041China Institute of Geographic Sciences and Natural Resources Research Chinese Academy of SciencesBeijing 100101China

Mud flows are common phenomena in mountainous areas,which can threaten human safety and cause property losses under certain extreme *** the dynamic characteristics of mud flows,especially in the vertical direction,is helpful for risk reduction and hazard *** this study,a 2D depth-resolved numerical model based on Herschel-Bulkley rheology was developed to study the vertical structures of unsteady mud flows with a *** numerical model was solved by the projection method,and the free surface of mud flows was captured through the VOF *** fully validate this new model,a series of laboratory experiments involving dam break mud flows were conducted,and the mud flow heights,bottom pressures and envelopes of mud residuum were *** numerical model proposed in this study was first validated by the steady-state solution for uniform flows of Herschel-Bulkley fluid on an inclined ***,the simulated and measured mud flow heights,bottom pressures at different x locations and envelopes with different bed slopes showed good ***,the numerical results for a Herschel-Bulkley fluid dam break flow were used to validate the proposed model,which further revealed good *** that,the scenarios in which mud flows impact on a structure were numerically studied,and the vertical profiles of the front velocity and impact pressure on the structure were analyzed and *** results show that a plug layer was formed in the mud flow under unsteady and nonuniform flow conditions,and the impact pressure on the structure was dominated by the dynamic *** addition,the vertical position with the maximum impact pressure acting on the structure was not at the bottom or the surface of the mud flows,and the normalized vertical position rose as the yield stress and consistency coefficient increase for Herschel-Bulkley fluids.

关键词： Mud flows Herschel-Bulkley rheology Depth-resolved model Numerical simulation Vertical profiles

Numerical Simulation of the Vortex-Induced Vibration of A Curved Flexible Riser in Shear Flow

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China Ocean Engineering 2018年第3期32卷 301-311页

作者： ZHU Hong-jun lin peng-zhi State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Southwest Petroleum University State Key Laboratory of Hydraulics and Mountain River Engineering Sichuan University

A series of fully three-dimensional(3 D) numerical simulations of flow past a free-to-oscillate curved flexible riser in shear flow were conducted at Reynolds number of 185–1015. The numerical results obtained by the two-way fluid–structure interaction(FSI) simulations are in good agreement with the experimental results reported in the earlier study. It is further found that the frequency transition is out of phase not only in the inline(IL) and crossflow(CF) directions but also along the span direction. The mode competition leads to the non-zero nodes of the rootmean-square(RMS) amplitude and the relatively chaotic trajectories. The fluid–structure interaction is to some extent reflected by the transverse velocity of the ambient fluid, which reaches the maximum value when the riser reaches the equilibrium position. Moreover, the local maximum transverse velocities occur at the peak CF amplitudes, and the values are relatively large when the vibration is in the resonance regions. The 3 D vortex columns are shed nearly parallel to the axis of the curved flexible riser. As the local Reynolds number increases from 0 at the bottom of the riser to the maximum value at the top, the wake undergoes a transition from a two-dimensional structure to a 3 D one. More irregular small-scale vortices appeared at the wake region of the riser, undergoing large amplitude responses.

关键词： vortex-induced vibration flexible riser shear flow fluid–structure interaction computational fluid dynamics

Recent advances of allenes in the first-row transition metals catalyzed C-H activation reactions

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Chinese Chemical Letters 2019年第8期30卷 1495-1502页

作者： Xiang-Lei Han peng-peng lin Qingjiang Li School of Pharmaceutical Sciences Sun Yat-sen UniversityGuangzhou 510006China State Key Laboratory of Natural and Biomimetic Drugs Peking UniversityBeijing 100191China

Transition-metal-catalyzed C–H activation reaction has proven to be a powerful and efficient tool for the formation of diverse C-C and C–X bond and construction of functional complex *** the viewpoint of sustainable chemistry,the first-row transition metals,such as Mn,Fe,Co,Ni and Cu,have been recognized as cheap,environmentally friendly and reactively effective catalysts for a number of C-H functionalization ***,compared with the commonly used alkenes and alkynes in the first-row transition-metal-catalyzed C–H activations,considerable achievements have just been made by the use of structurally unique and reactively rich allenes as coupling partners in recent *** review summarizes the recent progress of the first-row transition-metal-catalyzed C–H activations with allenes.

关键词： Allene C-H functionalization First-row transition metal Annulation Regioselectivity

Probing the Missing Baryons via kSZ Stacking

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Research in Astronomy and Astrophysics 2016年第4期16卷 121-128页

作者： Han Miao Wei-peng lin peng-Jie Zhang Key Laboratory for Research in Galaxies and Cosmology Shanghai Astronomical Observatory School of Physics and Astronomy Sun Yat-Sen University Center for Astronomy and Astrophysics Department of Physics and Astronomy Shanghai Jiao Tong University

Kinetic Sunyaev-Zel＇dovich （kSZ） stacking has great potential to become a powerful probe of missing baryons, due to advances in CMB experiments and galaxy surveys. In this paper, we study kSZ stacking in hydrodynamic simulations with different gastrophysics. We quantify the kSZ stacking signal as a function of halo mass, redshift and projection depth. We compare between different simulations to estimate the impact of gastrophysics such as cooling and supernova feedback. Furthermore, we measure the contribution from warm-hot intergalactic medium （WHIM）, which is believed to be the reservoir for most, if not all, missing baryons. We find that the WHIM contribution is significant, at the level of ~ 10%-70%, depending on the angular separation from the stacked halos and other factors. However, contribution from the intracluster medium along the line of sight is in general non-negligible. This complexity requires more detailed and comprehensive analysis on probing the missing baryons with kSZ stacking.

关键词： cosmology: theory -- large scale structure -- kinetic Sunyaev-Zel'dovich effect -- missingbaryons

Multi-Bit Sliding Stack Decoding Algorithm for OVXDM

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China Communications 2018年第4期15卷 179-191页

作者： peng lin yafeng wang daoben li Key Laboratory of Universal Wireless Communications Ministry of Education Beijing University of Posts and Telecommunications Beijing 100876 China

Overlapped x domain multiplexing(OVXDM) is a promising encoding technique to obtain high spectral efficiency by utilizing inter-symbol interference(ISI) intelligently. However, the computational complexity of maximum likelihood sequence detection(MLSD) increases exponentially with the growth of spectral efficiency in OVXDM, which is unbearable for practical implementations. In this paper, based on a novel path metric associating adjacent symbols, we propose a multi-bit sliding stack decoding(Multi-Bit SSD) algorithm to achieve multiple-bit decoding simultaneously in OVXDM. Theoretical analysis is provided for the algorithm, which indicates the relationship between the performance and parameters including multiplexing waveform, overlapping fold and sliding window size. Simulation results show that the proposed algorithm can achieve better decoding performance and higher spectral efficiency than conventional fast decoding algorithms.

关键词： overlapped multiplexing princi-ple maximum likelihood (ML) rule spectralefficiency bit error rate (BER).