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Chinese Journal of Chemistry 2023年第24期41卷 3521-3527页

作者： Xing Gao Xiaoxiao Ren Wei Deng Xingang Zhang Key Laboratory of Organofluorine Chemistry Shanghai Institute of Organic ChemistryUniversity of Chinese Academy of Sciences Chinese Academy of Sciences345 Lingling RoadShanghai200032 China School of Chemistry and Material Sciences Hangzhou Institute for Advanced StudyUniversity of Chinese Academy of Sciences1 Sub-lane XiangshanHangzhouZhejiang310024 China

Despite the paramount applications of organofluorine compounds in life and materials sciences,efficient strategies for stereoselectively constructing the C(sp^(3))-CF_(2)R bond at the stereogenic center remain limited.Here,we report a copper-catalyzed hydrodifluoroallylation of cyclopropenes and alkenyl boronates with 3,3-difluoroallyl sulfonium salts(DFASs).The use of DFASs overcomes the previous challenge of suppressing the reduction of fluoroalkylating reagents with M-H species.The reaction provides an array of gem-difluoroallyl cyclopropanes and borylalkanes with high efficiency and stereoselectivity under mild reaction conditions.Using chiral phosphine ligand could provide gem-difluoroallyl borylalkanes with high enantioselectivities,paving a new way for the catalytic asymmetric fluoroalkylation with ubiquitous alkenes.The advantages of this protocol are synthetic convenience,high functional group tolerance,and the synthetic versatility of the resulting gem-difluoroallyl cyclopropanes and borylalkanes.The synthetic utility of this approach has also been demonstrated by the diversified transformations of the gem-difluoroallylated products and the rapid synthesis of bioactive molecule analogs.

关键词： Asymmetric catalysis Copper hydride Cross-coupling Synthetic methods Hydrofluoroalkylation Sulfonium salts

Review of Operational Control Strategy for DC Microgrids with Electric-hydrogen Hybrid Storage Systems

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CSEE Journal of Power and Energy Systems 2022年第2期8卷 329-346页

作者： wei Pei Xue Zhang Wei Deng Chenghong Tang Liangzhong Yao the Institute of Electrical Engineering Chinese Academy of SciencesBeijing 100190 University of Chinese Academy of Sciences Beijing 100049China the Institute of Electrical Engineering Chinese Academy of SciencesBeijing 100190China the NARI Group Corporation Nanjing 211106China the School of Electrical Engineering and Automation Wuhan UniversityWuhan 430072China

Hydrogen production from renewable energy sources(RESs)is one of the effective ways to achieve carbon peak and carbon neutralization.In order to ensure the efficient,reliable and stable operation of the DC microgrid(MG)with an electric-hydrogen hybrid energy storage system(ESS),the operational constraints and static dynamic characteristics of a hydrogen energy storage system(HESS)needs to be fully considered.First,different hydrogen production systems,using water electrolysis are compared,and the modeling method of the electrolyzer is summarized.The operational control architecture of the DC MG with electric-hydrogen is analyzed.Combined with the working characteristics of the alkaline electrolyzer,the influence of hydrogen energy storage access on the operational mode of the DC MG is analyzed.The operational control strategies of the DC MG with electric-hydrogen hybrid ESS are classified and analyzed from four different aspects:static and dynamic characteristics of the hydrogen energy storage system,power distribution of the electric-hydrogen hybrid ESS and the efficiency optimization of hydrogen energy storage.Finally,the advantages of a modular hydrogen production system(HPS)are described,and the technical problems and research directions in the future are discussed.

关键词： Hydrogen energy DC microgrid modeling method operation control renewable energy sources

Operational Control of Low-voltage MTDC Systems in a Cyber-physical Environment

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CSEE Journal of Power and Energy Systems 2022年第6期8卷 1569-1582页

作者： Wei Deng wei Pei Ningning Li Xue Zhang Yin Yi Li Kong Institute of Electrical Engineering Chinese Academy of SciencesBeijing 100190China School of Electronic Electrical and Communication Engineering(EECE)University of Chinese Academy of SciencesBeijing 100049China

Based on the standardized cyber-physical modeling and communication system-IEC 61850,this paper establishes the operational control architecture of a low-voltage multi-terminal DC(LV-MTDC)system.The coordinated operational control strategies,including power electronic transformer(PET),and voltage source converter(VSC),are proposed.Then a cyberphysical model of the system based on IEC 61850 is built,according to the application requirements of operational control in the LV-MTDC system.On this basis,the implementation method of system operational control based on IEC 61850 is proposed,including the software/hardware design of the intelligent electronic device(IED),dispatching operations and uninterrupted power supply.The simulation environment is further built to verify the system operational control technology,and the test platform is used to carry out the actual tests.The research results show that the operational control technology for the LV-MTDC system proposed in this paper is feasible,which can guarantee the rapid and accurate information exchange of control commands and settings,and thus effectively realize the operational control of the LV-MTDC system under complex conditions.

关键词： Cyber-physical system distributed energy resources IEC 61850 intelligent electronic device low-voltage multi-terminal DC system

Review on grid-forming converter control methods in high-proportion renewable energy power systems

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Global Energy Interconnection 2022年第3期5卷 328-342页

作者： Yuting Teng Wei Deng wei Pei Yifeng Li Li Ding Hua Ye Institute of Electrical Engineering Chinese Academy of Sciences Beijing 100190P.R.China University of Chinese Academy of Sciences Beijing 100049P.R.China

Grid-forming(GFM)converters can provide inertia support for power grids through control technology,stabilize voltage and frequency,and improve system stability,unlike traditional grid-following(GFL)converters.Therefore,in future“double high”power systems,research on the control technology of GFM converters will become an urgent demand.In this paper,we first introduce the basic principle of GFM control and then present five currently used control strategies for GFM converters:droop control,power synchronization control(PSC),virtual synchronous machine control(VSM),direct power control(DPC),and virtual oscillator control(VOC).These five strategies can independently establish voltage phasors to provide inertia to the system.Among these,droop control is the most widely used strategy.PSC and VSM are strategies that simulate the mechanical characteristics of synchronous generators;thus,they are more accurate than droop control.DPC regulates the active power and reactive power directly,with no inner current controller,and VOC is a novel method under study using an oscillator circuit to realize synchronization.Finally,we highlight key technologies and research directions to be addressed in the future.

关键词： Grid-forming control Droop control Power synchronization control Virtual synchronous machine control Direct power control Virtual oscillator control

Advances in the construction of diverse SuFEx linkers

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National Science Review 2023年第6期10卷 226-244页

作者： Daming Zeng wei-Ping deng Xuefeng Jiang Shanghai Frontiers Science Center of Optogenetic Techniques for Cell Metabolism School of Pharmacy East China University of Science and Technology Shanghai Key Laboratory of Green Chemistry and Chemical Process School of Chemistry and Molecular Engineering East China Normal University

Sulfur fluoride exchange(SuFEx),a new generation of click chemistry,was first presented by Sharpless,Dong and co-workers in 2014.Owing to the high stability and yet efficient reactivity of the SⅥ-F bond,SuFEx has found widespread applications in organic synthesis,materials science,chemical biology and drug discovery.A diverse collection of SuFEx linkers has emerged,involving gaseous SO2F2and SOF4hubs;SOF4-derived iminosulfur oxydifluorides;O-,N-and C-attached sulfonyl fluorides and sulfonimidoyl fluorides;and novel sulfondiimidoyl fluorides.This review summarizes the progress of these SuFEx connectors,with an emphasis on analysing the advantages and disadvantages of synthetic strategies of these connectors based on the SuFEx concept,and it is expected to be beneficial to researchers to rapidly and correctly understand this field,thus inspiring further development in SuFEx chemistry.

关键词： SuFEx SuFEx linker SVI–F bond synthetic strategy

Characteristics of air flow driven by the free surface of the open channel

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Journal of Hydrodynamics 2022年第1期34卷 69-75页

作者： Jing Gong Jun deng Wang-ru wei wei-wei Li State Key Laboratory of Hydraulics and Mountain River Engineering Sichuan UniversityChengdu610065China

Spillway tunnels are a key structure in large-scale water conservancies. The high-head water inlet makes the water surface-velocity extremely high, and the air is driven by the free surface of the water to move downstream. This paper studies the air velocity distribution above the water surface through the model tests, under the assumption that the airflow is a turbulent boundary layer with a rough interface, and the influence of the water depth and the water velocity on the air velocity distribution is analyzed. It is shown that the air velocity is in an exponential distribution. As the measured position moves upward, the air velocity gradually decreases, and the gradient decreases. When the water depth increases, the air velocity increases but with the same distribution form. With the increase of the water surface-velocity, the air velocity at the same measuring point increases, the variation range near the water surface is large, the air boundary layer height increases slightly, and the index coefficient of the air velocity distribution function decreases. Through numerical fitting, the calculation formula of the air boundary layer thickness at different water surface velocities is obtained, along with the numerical value of the index coefficient.

关键词： Open channel air velocity distribution air boundary layer height index coefficient

Air-tolerant direct reductive N-methylation of amines using formic acid via simple inorganic base catalysis

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Chinese Chemical Letters 2020年第1期31卷 111-114页

作者： Yan Huang Wei Deng Bo-Lin Lin School of Chemical and Environmental Engineering Shanghai Institute of TechnologyShanghai 201418China School of Technology and Physical Science ShanghaiTech UniversityShanghai 201210China

The construction of N-methyl amine moieties is an important reaction that has found numerous applications.Development of new methylation agents that are more environmentally benign than classical agents,such as iodomethane and methyl sulfate,is still highly desirable.Herein,we report a convenient protocol for direct reductive N-methylation of amines using formic acid as the methylation agent via simple inorganic base catalysis.The present protocol operates under transition-metal-free and air-tolerant conditions.Both the catalyst,K2 HPO4,and the reductant,polymethylhydrosiloxane(PMHS),are cheap and easily separable from the crude reaction product mixture.Mechanistic investigations suggest that the reaction occur through the formation of an acetal inte rmediate followed by the C-N bond formation.

关键词： Air tolerant N-Methylation Formic acid Simple inorganic bas Transition-metal-free

The Importance of the Shape Parameter in a Bulk Parameterization Scheme to the Evolution of the Cloud Droplet Spectrum during Condensation

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Advances in Atmospheric Sciences 2023年第1期40卷 155-167页

作者： Jun ZHANG Jiming SUN Wei Deng Wenhao HU Yongqing WANG Laboratory of Cloud-Precipitation Physics and Severe Storms Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China Nanjing University of Information and Technology Nanjing 210044China University of Chinese Academy of Sciences Beijing 100049China Beijing Key Laboratory of Cloud Precipitation and Atmospheric Water ResourcesBeijing 100089China

The shape parameter of the Gamma size distribution plays a key role in the evolution of the cloud droplet spectrum in the bulk parameterization schemes. However, due to the inaccurate specification of the shape parameter in the commonly used bulk double-moment schemes, the cloud droplet spectra cannot reasonably be described during the condensation process. Therefore, a newly-developed triple-parameter condensation scheme with the shape parameter diagnosed through the number concentration, cloud water content, and reflectivity factor of cloud droplets can be applied to improve the evolution of the cloud droplet spectrum. The simulation with the new parameterization scheme was compared to those with a high-resolution Lagrangian bin scheme, the double-moment schemes in a parcel model, and the observation in a 1.5D Eulerian model that consists of two cylinders. The new scheme with the shape parameter varying with time and space can accurately simulate the evolution of the cloud droplet spectrum. Furthermore, the volume-mean radius and cloud water content simulated with the new scheme match the Lagrangian analytical solutions well, and the errors are steady, within approximately 0.2%.

关键词： cloud microphysics parameterization cloud droplet spectrum double-moment scheme shape parameter

Observer-based event-triggered control for linear MASs under a directed graph and DoS attacks

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Journal of Control and Decision 2022年第3期9卷 384-396页

作者： Shuo-Qiu Zhang wei-wei Che Chao deng College of the Institute of Complexity Science Shandong Key Laboratory of Industrial Control TechnologyQingdao UniversityQingdaoPeople’s Republic of China Institute of Advanced Technology Nanjing University of Posts and TelecommunicationsNanjingPeople’s Republic of China

In this paper,we investigate the observer-based event-triggered consensus problem for linear multi-agent systems(MASs)under a directed graph and denial-of-service(DoS)attacks.A type of DoS attacks launched by malicious attackers at irregular intervals is considered,which can cause communication channel disruption.A novel event-triggered secure control scheme based on a closed-loop observer is proposed to determine the scheduling of the controller update,and a separation method with less conservativeness is employed to design the controller and observer gains.Then,the frequency and duration of DoS attacks that can be tolerated are analysed for the observer-based secure consensus problem.In addition,a strictly positive minimal event-triggered time interval for each agent is designed with the help of the proposed eventtriggered condition to eliminate the Zeno behaviour.Finally,a numerical simulation is given to verify the theoretical analysis.

关键词： Directed graph DoS attacks event-triggered mechanism consensus control multi-agent systems

Quantitatively Evaluating the Erosion and Preservation of Supergene Oxide Zones:Evidence from the Yulong Porphyry Cu Deposit,Eastern Tibetan Plateau

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Journal of Earth Science 2024年第1期35卷 280-282页

作者： Xiao-Dong deng Jian-wei Li State Key Laboratory of Geological Processes and Mineral Resources and School of Earth ResourcesChina University of GeosciencesWuhan 430074China

INTRODUCTION.Weathering and erosion of sulfide ore deposits are important for understanding the post-mineralization processes that have significant effects on the preservation of primary orebodies(Velasco et al.,2013;Braxton et al.,2009;Brimhall et al.,1985).Supergene oxide zones are often developed in sulfide ore deposits,and are mainly composed of iron oxides and hydroxides zones in weathering profile(Andrew,1984;Thornber et al.,1981).

关键词： Eastern Tibetan weathering