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Impurity Effects at Surfaces of a Photon-Dressed Bi2Se3 Thin Film

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Chinese Physics Letters 2018年第10期35卷 72-76页

作者： Qiu-Shi wang Bin Zhang Wei-Zhu Yi Meng-Nan Chen baigeng wang R.Shen National Laboratory of Solid State Microstructures and Department of Physics Nanjing University Nanjing 210093 School of Science Hangzhou Dianzi University Hangzhou 310018 Collaborative Innovation Center of Advanced Microstructures Nanjing 210093

We investigate the impurity effects on surfaces of a thin film topological insulator, applied by an off-resonant circular polarized light. It is found that the off-resonant driving induces a quantized total Hall conductivity, when the driving strength is larger than a critical value and the Fermi level lies in the band gap, indicating that our system is converted into the topological phase. We also find that with the increasing disorder strength, the Dirac masses of top and bottom surfaces are renormalized and then fixed to half of their initial values, respectively,which will shrink the widths of the half-integer plateau of anomalous Hall conductivities.

关键词： Impurity Effects at Surfaces of a Photon-Dressed Bi2Se3 Thin Film Bi

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Dynamic Output Feedback Based Robust Controller Design for Selective Catalytic Reduction Systems

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Dynamic Output Feedback Based Robust Controller Design for S...

Carrier balance and linear magnetoresistance in type-II Weyl semimetal WTe2

第31届中国过程控制会议（CPCC2020）

作者： wang baigeng LI Shurong Automation school Beijing University of Posts and Telecommunications

Selective catalytic reduction(SCR) is an effective way to deal with the flue gas at the outlet of coal-fired boiler. The working process of SCR systems is to use the ammonia(NH3) adsorbed on the catalyst to react with nitrogen oxide(NOx) to generate nitrogen and water. This paper presents an observer based dynamic output feedback control for SCR systems. Since NH3 coverage ratio cannot be measured directly, a reduced order observer is designed first. And then it is proved that the error of observer tends to 0 by using Lyapunov function. Furthermore, the dynamic equation of the composite system including the observer state is obtained. Finally, the controller is designed to adjust the rate of NH3 injection in order to satisfy the industrial demand.

关键词： Selective catalytic reduction Dynamic output feedback Reduced order observer Robust control Lyapunov function

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Frontiers of physics 2017年第3期12卷 73-80页

作者： Xing-Chen Pan Yiming Pan Juan Jiang Huakun Zuo Huimei Liu Xuliang Chen Zhongxia Wei Shuai Zhang Zhihe wang Xiangang Wan Zhaorong Yang Donglai Feng Zhengcai Xia Liang Li Fengqi Song baigeng wang Yuheng Zhang Guanghou wang National Laboratory of Solid State Microstructures Collaborative Innovation Center of Advanced Microstructures and Colleae of Physics. Naniina University. Nanjina 210093. China State Key Laboratory of Surface Physics Coliaborative Innovation Center of Advanced MicrostructuresDepartment of Physics and Advanced Materials Laboratory Fudan University Shanghai 200433 China Wuhan National High Magnetic Field Center Huazhong University of Science and Technology Wuhan 430074 China High Magnetic Field Laboratory Chinese Academy of Sciences Hefei 230031 China

Unsaturated magnetoresistance （MR） has been reported in type-II Weyl semimetal WTe2, manifested as a perfect compensation of opposite carriers. We report linear MR （LMR） in WTe2 crystals, the onset of which was identified by constructing the MR mobility spectra for weak fields. The LMR further increased and became dominant for fields stronger than 20 T, while the parabolic MR gradually decayed. The LMR was also observed in high-pressure conditions.

关键词： WTe2 type-II Weyl semimetal carrier balance linear magnetoresistance

Transport Properties of Two Coupled Quantum Dots Under Optical Pumping

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Journal of Semiconductors 2006年第4期27卷 598-603页

作者：葛传楠温俊彭菊王伯根南京大学物理系固体微结构国家实验室南京210093

Using the Keldysh-Green function,we present a theoretical study on the electron transport properties of two coupled quantum dots under optical pumping. Plateaus in the I-V curve and resonant peaks in the transmission coefficient occur and can be explained by the local electron density of states in the quantum dots. The effects of the optical pumping frequency and intensity on the transport properties of the system are also discussed. The electron dynamical localization phenomenon occurs when the optical pumping frequency is equal to the discrete hole energy level. This result can be used to realize optical control switches.

关键词： Keldysh-Green function optical pumping quantum dot electron transport dynamical localization

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Hund-like interaction mechanism for the Kondo resonance splitting in a carbon nanotube quantum dot

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Hund-like interaction mechanism for the Kondo resonance spli...

Dual modulation of homogeneous nanomaterialization and electrochemical activation enhancing zinc ion storage

量子电荷和自旋输运研讨会

作者： Dept. of Physics, Nanjing University baigeng wang Collaborators: Dept. of Physics, Nanjing University, Prof. Dingyu Xing Dr. Jin wang Dr. Zhigao Chen Dept. of Physics, Hong Kong University, Prof. Jian wang

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Science China Chemistry 2025年第1期68卷 385-393页

作者： Jianwei wang Huan wang Kangning wang Wenhui wang Wenlin Zhang Yanzhong Zhen School of Chemistry & Chemical Engineering Yan'an University

Vanadium-based electrode materials are widely investigated,but the low specific capacity and slow electrochemical kinetics in aqueous zinc-ion batteries still limit their commercial ***,the VS2/Ca V4O9material with the morphology of nanoflower was synthesized by a one-step hydrothermal *** to the blocky structure of pure VS2material,the VS2/Ca V4O9material is composed of thinner homogeneous *** open structures could provide abundant electrochemical active sites and ion transport channels,and then promote the electrochemical reaction *** addition,they can also buffer the bulk strain during the reaction *** improve the utilization of vanadium elements,an in-situ electrochemical activation strategy is used to explore the storage performance of the VS2/Ca V4O9material,the different activation voltage range of 0.4–1.6 and 0.4–1.4 V are selected,*** with the longer activation plateau of activated-VS2,the VS2/Ca V4O9cathode could quickly reach the activation state in the range of 1.4–1.6 V and cause the release of additional Zn storage sites *** VS2/Ca V4O9cathode delivers a higher power density of 37,000 W kg-1and a significant energy density of 423 Wh *** the high current density of 15 A g-1,the VS2/Ca V4O9cathode still has a discharge capacity of 183.9m Ah g-1after 5,000 cycles,and the capacity decay rate per cycle is only 0.0042%.Continuous cyclic voltammetry （CV） curves,electrochemical impedance spectroscopy （EIS） measurements,density functional theory （DFT） calculation and galvanostatic intermittent titration technique （GITT） measurements demonstrate that the VS2/Ca V4O9cathode has a faster ion diffusion/charge transfer ***,the assembled flexible device has an excellent mechanical stability.

关键词： dual modulation homogeneous nanomaterialization electrochemical activation zinc ion storage

An Iterated Greedy Algorithm with Memory and Learning Mechanisms for the Distributed Permutation Flow Shop Scheduling Problem

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Computers, Materials & Continua 2025年第1期82卷 371-388页

作者： Binhui wang Hongfeng wang College of Information Science and Engineering Northeastern UniversityShenyang110819China

The distributed permutation flow shop scheduling problem(DPFSP)has received increasing attention in recent *** iterated greedy algorithm(IGA)serves as a powerful optimizer for addressing such a problem because of its straightforward,single-solution evolution ***,a potential draw-back of IGA is the lack of utilization of historical information,which could lead to an imbalance between exploration and exploitation,especially in large-scale *** a consequence,this paper develops an IGA with memory and learning mechanisms(MLIGA)to efficiently solve the DPFSP targeted at the ***,we incorporate a memory mechanism to make a more informed selection of the initial solution at each stage of the search,by extending,reconstructing,and reinforcing the information from previous *** addition,we design a twolayer cooperative reinforcement learning approach to intelligently determine the key parameters of IGA and the operations of the memory ***,to ensure that the experience generated by each perturbation operator is fully learned and to reduce the prior parameters of MLIGA,a probability curve-based acceptance criterion is proposed by combining a cube root function with custom *** last,a discrete adaptive learning rate is employed to enhance the stability of the memory and *** ablation experiments are utilized to verify the effectiveness of the memory mechanism,and the results show that this mechanism is capable of improving the performance of IGA to a large ***,through comparative experiments involving MLIGA and five state-of-the-art algorithms on 720 benchmarks,we have discovered that MLI-GA demonstrates significant potential for solving large-scale *** indicates that MLIGA is well-suited for real-world distributed flow shop scheduling.

关键词： Distributed permutation flow shop scheduling makespan iterated greedy algorithm memory mechanism cooperative reinforcement learning

Controlled cationic ring-opening polymerization of L-lactide by organic ion pair: novel approach to isotactic-rich and crystalline polylactide

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Science China Chemistry 2025年第1期68卷 394-402页

作者： Zhiqiang Ding Mingqian wang Zijing Zhou Bin wang Yuesheng Li Tianjin Key Laboratory of Composite & Functional Materials School of Materials Science and Engineering Tianjin University

Living/controlled cationic ring-opening polymerization （ROP） of L-lactide is a promising approach to isotactic-rich and crystalline poly（L-lactide）.In contrast with the unsubstituted lactones,L-LA can not be polymerized by organic Lewis acids or carbenium ions,and the state of the art in this field is the cationic ROP of L-LA catalyzed by Br?nsted acid/alcohol system via activated monomer ***,we reported the first example of controlled cationic ROP of L-LA by using Meerweintype ion pair[Me3O]+[B（C6F5）4]-as the catalyst.[Me3O]+[B（C6F5）4]-promoted rapid L-LA cationic polymerization in the absence of alcohol,producing isotactic-rich and crystalline PLLA without transesterification and epimerization side *** activated chain end mechanism,involving twice SN2 substitution and configuration-inversion （S→R→S） with the assistance of released Me2O,was proposed and further verified by density functional theory and control *** work expands the catalytic toolbox of isotactic-rich and crystalline polylactide *** represents a unique example of cationic-controlled polymerization of L-LA catalyzed by an organic ion pair.

关键词： organic ion pair controlled cationic ring-opening polymerization activated chain end mechanism isotactic-rich polylactide

Impact of Startup Strategy and Buffer Tank Volume on the Compressor Inlet State for a 3-MW sCO2 Brayton Cycle

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Journal of Thermal Science 2025年第1期34卷 159-175页

作者： ZHAO Decai wang Bo Key Laboratory of Advanced Energy and Power Institute of Engineering Thermophysics(IET)Chinese Academy of Sciences (CAS) University of Chinese Academy of Sciences

The supercritical carbon dioxide（sCO2） Brayton cycle system has become an emerging and highly promising method of thermal power conversion due to its efficiency advantage,system compactness,and excellent adaptability of the heat *** the low carbon sCO2Brayton cycle testbed with cycle output power approaching 3 MW,a relatively detailed dynamic simulation model of the entire system is constructed to explore the dynamic response characteristics of the system with different startup strategies and different buffer tank volumes during the startup *** simulation results indicate that the smaller the volume of the buffer tank,the more rapid and obvious the parameter fluctuation in the buffer tank during the *** the allowable relative deviation limit of density is 5%,then the ratio of the buffer tank volume to the volume of the entire closed loop should not be lower than 36.80%.The strategy of simultaneous temperature and speed increase during turbine bypass start can effectively reduce the fluctuation of compressor inlet parameters and reach the steady-state more *** paper provides the recommended matching table for the opening of the turbine bypass valve（TBV） and the main regulating valve（MGV） to reduce the parameter fluctuation during the bypass *** effectiveness of the proposed turbine bypass and bypass switching startup strategy is verified by simulation,which may be used as a reference for test bench's future debugging and operation.

关键词： buffer tank dynamic characteristic dynamic model sCO2 Brayton cycle startup strategy