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Isocyanide-Based One-Pot Cascade Synthesis of 3-Acyl Isoindolinones

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Chinese Journal of Chemistry 2024年第3期42卷 259-263页

作者： jia liu Yi-Ming Zhu Xiao-ping Xu Shun-Jun ji Key Laboratory of Organic Synthesis of jiangsu Province College of ChemistryChemical Engineering and Materials Science & Collaborative Innovation Center of Suzhou Nano Science and TechnologySoochow UniversitySuzhouJiangsu215123 China Suzhou Baolidi Functional Materials Research Institute SuzhouJiangsu215144 China

A series of 3-acyl-substituted isoindolinone derivatives were synthesized in a one-pot manner via the reaction of o-bromobenzaldehydes,isocyanides,and carboxylic acids in the presence of palladium catalyst and base. The reaction employing easily available starting materials features simple operation and high efficiency. The mechanistic study showed that the reaction might undergo 1) Pd-catalyzed [3+2] cyclization of o-bromobenzaldehyde with isocyanide and the re-insertion of another molecule of isocyanide,2) addition of carboxylic acid to in situ formed ketenimine followed by a rearrangement relay to give 3,3-diacyl-substituted isoindolinone derivative. Further transformations of the obtained products through decarbonylation could also be realized.

关键词： One-pot reaction Isocyanide Pd catalysis Rearrangement reaction Isoindolinone

Effects of Grain Size and Cryogenic Temperature on the Strain Hardening Behavior of VCoNi Medium‑Entropy Alloys

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Acta Metallurgica Sinica(English Letters) 2023年第6期36卷 973-986页

作者： Guo‑Dong liu Xue‑Mei Luo ji‑Peng Zou Bin Zhang Guang‑ping Zhang Shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China School of Materials Science and Engineering University of Science and Technology of ChinaShenyang 110016China Key Laboratory for Anisotropy and Texture of Materials Ministry of EducationSchool of Materials Science and EngineeringNortheastern UniversityShenyang 110819China

The mechanical behavior of VCoNi medium-entropy alloys with five different grain sizes at three different temperatures was *** VCoNi alloys with different grain sizes exhibit a traditional strength–ductility trade-off at 77 K,194 K and 293 *** the yield strength and the uniform elongation of the VCoNi alloys with similar grain size increase with decreasing the deformation temperature from 293 to 77 *** strain hardening rate recovery characterized by an evident up-turn behavior at stage II is observed in VCoNi alloys with the grain size above 11.1μ*** is found that the extent of the strain hardening rate recovery increases with increasing grain size or decreasing deformation *** may mainly result from the faster increase in the dislocation multiplication rate caused by the decrease in the dislocation mean free path,the decrease in the absorption of dislocations by grain boundaries and the dynamic recovery from the cross-slip with increasing grain size,as well as the suppressed dynamic recovery at cryogenic *** critical grain sizes for the occurrence of the recovery of strain hardening rate are determined to be around 9.5μm,8.3μm and 3μm for alloys deformed at 293 K,194 K and 77 K,*** basic mechanism for the strain hardening behavior of the VCoNi alloys associated with grain size and deformation temperature is analyzed.

关键词： Medium-entropy alloy Strain hardening rate Cryogenic temperature Grain size Slip band refinement

Energy Spectra, g Factors and Their Pressure-Induced and/or Thermal Shifts of SrTiO3:Cr3+ and SrTiO3:Mn4+ Ⅲ: R-Line Thermal Shifts of SrTiO3:Mn4+

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Communications in Theoretical Physics 2001年第11期36卷 463-468页

作者： MA Dong-ping ZHANG ji-ping Department of Applied Physics Sichuan University Chengdu 610065 China International Centre for Materials Physics The Chinese Academy of Sciences Shenyang 110015 China Department of Applied Physics Sichuan University Chengdu 610065 China

By taking into account all the irreducible representations and their components in the electron-phonon interaction (EPI) as well as all the levels and the admixtures of basic wavefunctions within d3 electronic configuration,the values of the parameters in the expressions of thermal shift (TS) from EPI for the ground level, R level and R line of SrTiO3:Mn4+ have been evaluated; the R-line TS and various contributions to it have been calculated in the low-temperature region. It is found that all the three terms of R-line TS from EPI relevant to the lattice vibration are red shifts. The Raman term is the largest, the neighbor-level term is the second, and the optical-branch term is very small over the range of T ≤ 80 K. The contribution to R-line TS from thermal expansion has been approximately neglected in this work. The very strong EPI relevant to its lattice vibration for SrTiO3:Mn4+ causes its R-line TS to be an unusually large red-shift. Only by taking into account the strong softening of the low-frequency acoustic modes of the lattice vibration at low temperatures, can we successfully explain the variation of R-line TS of SrTiO3:Mn4+ with temperature.

关键词： crystal fields, optical properties, electron-phonon interaction, thermal shift, softening of acoustic modes

Coordination of Networked Nonlinear Multi-Agents Using a High-Order Fully Actuated Predictive Control Strategy

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IEEE/CAA Journal of Automatica Sinica 2022年第4期9卷 615-623页

作者： Guo-ping liu IEEE the Department of Electronic and Electrical Engineering Southern University of Science and Technology

This paper is concerned with the coordinative control problem of networked nonlinear multi-agents(NNM)with communication delays.A high-order fully actuated(HOFA)model is introduced to describe the nonlinear *** on this model,a HOFA predictive coordination method is proposed to compensate for the communication delays actively and achieve simultaneous stability and *** method largely simplifies the design of networked nonlinear multi-agents and makes the control performance be same for networked nonlinear multi-agents with and without communication *** analysis on the closed-loop systems derives the simultaneous stability and consensus criteria of networked nonlinear multiagents using the HOFA predictive coordination *** the presented way of designing HOFA predictive coordination controllers,a simulated example demonstrates the advantages of the proposed method.

关键词： method nonlinear coordination

Control Strategies for Digital Twin Systems

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IEEE/CAA Journal of Automatica Sinica 2024年第1期11卷 170-180页

作者： Guo-ping liu IEEE the Center for Control Science and Technology Southern University of Science and TechnologyShenzhen 518055China

With the continuous breakthrough in information technology and its integration into practical applications, industrial digital twins are expected to accelerate their development in the near future. This paper studies various control strategies for digital twin systems from the viewpoint of practical *** make full use of advantages of digital twins for control systems, an architecture of digital twin control systems, adaptive model tracking scheme, performance prediction scheme, performance retention scheme, and fault tolerant control scheme are proposed. Those schemes are detailed to deal with different issues on model tracking, performance prediction, performance retention, and fault tolerant control of digital twin systems. Also, the stability of digital twin control systems is analysed. The proposed schemes for digital twin control systems are illustrated by examples.

关键词： Digital twin control systems fault tolerant control model tracking performance prediction performance retention

Predictive Control of High-Order Fully Actuated Nonlinear Systems with Time-Varying Delays

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Journal of Systems Science & Complexity 2022年第2期35卷 457-470页

作者： liu Guo-ping Department of Electronic and Electrical Engineering Southern University of Science and TechnologyShenzhen 518055China

This paper investigates the control problem of high-order fully actuated nonlinear systems with time-varying delays in the discrete-time *** make the compensation for time-varying delays concise,active and universal,a novel nonlinear predictive control method is *** designed nonlinear predictive controller can achieve the same expected control performance as the nonlinear systems without *** the same time,the necessary and sufficient conditions for the stability of the closed-loop nonlinear predictive control systems are *** examples show that the proposed nonlinear predictive controller design method can completely compensate for the time-varying delays of nonlinear systems.

关键词： High-order fully actuated control systems nonlinear systems predictive control timevarying delays

Networked Learning Predictive Control of Nonlinear Cyber-Physical Systems

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Journal of Systems Science & Complexity 2020年第6期33卷 1719-1732页

作者： liu Guo-ping Department of Artificial Intelligence and Automation Wuhan UniversityWuhan 430072China

Cyber-physical systems integrate computing,network and physical environments to make the systems more efficient and cooperative,and have important and extensive application prospects,such as the Internet of *** paper studies the control problem of nonlinear cyber-physical systems with unknown dynamics and communication delays.A networked learning predictive control scheme is proposed for unknown nonlinear cyber-physical *** scheme recursively learns unknown system dynamics,actively compensates for communication delays and accurately tracks a desired *** multi-step predictors are presented to predict various step ahead outputs of the unknown nonlinear cyber-physical *** optimal design of controllers minimises a performance cost function which measures the tracking error predictions and control input increment *** system analysis leads to the stability criteria of closed-loop nonlinear cyber-physical systems employing the networked learning predictive control *** example illustrates the outcomes of the proposed scheme.

关键词： Cyber-physical systems learning control networked predictive control nonlinear systems

Tracking Control of Multi-Agent Systems Using a Networked Predictive PID Tracking Scheme

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IEEE/CAA Journal of Automatica Sinica 2023年第1期10卷 216-225页

作者： Guo-ping liu IEEE the Center for Control Science and Technology Southern University of Science and TechnologyShenzhen 518055China

With the rapid development of network technology and control technology,a networked multi-agent control system is a key direction of modern industrial control systems,such as industrial Internet *** paper studies the tracking control problem of networked multi-agent systems with communication constraints,where each agent has no information on the dynamics of other agents except their outputs.A networked predictive proportional integral derivative(PPID)tracking scheme is proposed to achieve the desired tracking performance,compensate actively for communication delays,and simplify implementation in a distributed *** scheme combines the past,present and predictive information of neighbour agents to form a tracking error signal for each agent,and applies the proportional,integral,and derivative of the agent tracking error signal to control each individual *** criteria of the stability and output tracking consensus of multi-agent systems with the networked PPID tracking scheme are derived through detailed analysis on the closed-loop *** effectiveness of the networked PPID tracking scheme is illustrated via an example.

关键词： Coordinative tracking control networked multiagent systems PID control predictive control

Maturing process of solitary wave train in a step-down chain

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Chinese Physics B 2012年第2期21卷 368-372页

作者： Xia ji-Hong Wang ping-jian liu Chang-Song Key Laboratory of Materials Physics Institute of Solid State PhysicsChinese Academy of SciencesHefei 230031China Department of Physics Chongqing University of Arts and SciencesChongqing 402160China

In a step-down chain a solitary wave （SW） evolves into an SW train （SWT）, but the formation of well-defined SWT takes time and space and little is known of the process from immature into mature SWT. We therefore perform a detailed numerical study of this process by analysing the local velocity amplitude and peak overlap of immature ordered SWs. The first SW continuously increases to maximal velocity amplitude and peak overlap until it is matured, but for following SWs there exist a minimal and maximal value of local velocity amplitude and, a minimal and maximal value of local peak overlap, clarifying the details of the energy propagation along the stepped chain. The immature and mature SWTs show the same dependence of the phase velocity on the SWs sequence. These provide guidelines for when or where the attention should be paid in the study of SWT.

关键词： granular systems solitary wave molecular dynamics simulation