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Low-temperature Synthesis of MoS2 @ CoS2 heterostructures in KSCN Molten Salt for Efficient Hydrogen Evolution Reaction

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材料导报 2020年第18期34卷 18001-18002页

作者： AI Wei He Song Institute of Flexible Electronics Northwestern Polytechnical UniversityXi’an 710072China

Transition metal sulfides(TMSs)have been recognized as potential electrocatalysts for hydrogen evolution reaction(heR),where the edges and defects of TMSs are known as the active sites[1-2].MoS2 with layered crystal structure is so far the most frequently investigated one,however,the associated heR activi-ty is restricted by its low conductivity because of the wide bandgap(1.73 eV)[3-4].Although constructing heterostructures,for example,MoS2@CoS2,presents higher heR activity,the synthetic methods are generally limited by either high-pressure hydrothermal or high-temperature annealing procedures,which lead to unsatisfactory electrochemical performance and low pro-ductivity[5-6].

关键词： annealing sulfide Transition

Note on higher-point correlation functions of the TT or JT deformed CFTs

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Science China(Physics,Mechanics & Astronomy) 2021年第9期64卷 15-28页

作者： song he Center for Theoretical Physics College of PhysicsJilin UniversityChangchun 130012China Max Planck Institute for Gravitational Physics(Albert Einstein Institute) Am M¨uhlenberg 1Golm 14476Germany

We investigate generic n-point correlation functions of conformal field theories(CFTs),with TT and JT deformations,in terms of the perturbative CFT approach.We systematically obtain the first order correction to the generic correlation functions of CFTs with TT or JT deformation.We compute the out of time ordered correlation function(OTOC)in the Ising model with TT or Jdeformation,which confirms that these deformations do not change the integrable property up to the first order level.

关键词： integrable deformation conformal field theory quantum chaos quantum integrability quantum entanglement

Rigid-Soft Coupled Robotic Gripper for Adaptable Grasping

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Journal of Bionic Engineering 2023年第6期20卷 2601-2618页

作者： Zhiyuan he Binbin Lian Yimin song Key Laboratory of Mechanism Theory and Equipment Design of Ministry of Education Tianjin UniversityTianjin300350China Department of Mechanical Engineering Tianjin Renai CollegeTianjin301636China

Inspired by the morphology of human fingers,this paper proposes an underactuated rigid-soft coupled robotic gripper whose finger is designed as the combination of a rigid skeleton and a soft tissue.Different from the current grippers who have multi-point contact or line contact with the target objects,the proposed robotic gripper enables surface contact and leads to flexible grasping and robust holding.The actuated mechanism,which is the palm of proposed gripper,is optimized for excellent operability based on a mathematical model.Soft material selection and rigid skeleton structure of fingers are then analyzed through a series of dynamic simulations by RecurDyn and Adams.After above design process including topology analysis,actuated mechanism optimization,soft material selection and rigid skeleton analysis,the rigid-soft coupled robotic gripper is fabricated via 3D printing.Finally,the grasping and holding capabilities are validated by experiments testing the stiffness of a single finger and the impact resistance of the gripper.Experimental results show that the proposed rigid-soft coupled robotic gripper can adapt to objects with different properties(shape,size,weight and softness)and hold them steadily.It confirms the feasibility of the design procedure,as well as the compliant and dexterous grasping capabilities of proposed rigid-soft coupled gripper.

关键词： Rigid-soft coupled robotic gripper Parameter optimization Dynamic simulation Adaptive grasping Robust holding

Global Stability of a Time-delayed Malaria Model with Standard Incidence Rate

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Acta Mathematicae Applicatae Sinica 2023年第2期39卷 211-221页

作者： song-bai GUO Min he Jing-an CUI School of Science Beijing University of Civil Engineering and ArchitectureBeijing 102616China Academy of Mathematics and Systems Science Chinese Academy of SciencesBeijing 100190China

A four-dimensional delay differential equations(DDEs)model of malaria with standard incidence rate is proposed.By utilizing the limiting system of the model and Lyapunov direct method,the global stability of equilibria of the model is obtained with respect to the basic reproduction number R_(0).Specifically,it shows that the disease-free equilibrium E^(0)is globally asymptotically stable(GAS)for R_(0)he endemic equilibrium E^(*)is GAS and E^(0)is unstable for R_(0)>1.Especially,to obtain the global stability of the equilibrium E^(*)for R_(0)>1,the weak persistence of the model is proved by some analysis techniques.

关键词： malaria model delay differential equations Lyapunov functional weak persistence global stability

CLOF Based Outlier Detection Algorithm of Temperature Data for Ethylene Cracking Furnace

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Journal of Harbin Institute of Technology(New Series) 2023年第4期30卷 50-57页

作者： Yidan Xin Shaolin Hu Wenzhuo Chen He Song School of Automation and Information Engineering Xi’an University of TechnologyXi’an 710048China Guangdong Provincial Key Lab.of Petrochemical Equipment and Fault Diagnosis School of AutomationGuangdong University of Petrochemical TechnologyMaoming 525000GuangdongChina

The flue temperature is one of the important indicators to characterize the combustion state of an ethylene cracker furnace,the outliers of temperature data can lead to the false alarm.Conventional outlier detection algorithms such as the Isolation Forest algorithm and 3-sigma principle cannot detect the outliers accurately.In order to improve the detection accuracy and reduce the computational complexity,an outlier detection algorithm for flue temperature data based on the CLOF(Clipping Local Outlier Factor,CLOF)algorithm is proposed.The algorithm preprocesses the normalized data using the cluster pruning algorithm,and realizes the high accuracy and high efficiency outlier detection in the outliers candidate set.Using the flue temperature data of an ethylene cracking furnace in a petrochemical plant,the main parameters of the CLOF algorithm are selected according to the experimental results,and the outlier detection effect of the Isolation Forest algorithm,the 3-sigma principle,the conventional LOF algorithm and the CLOF algorithm are compared and analyzed.The results show that the appropriate clipping coefficient in the CLOF algorithm can significantly improve the detection efficiency and detection accuracy.Compared with the outlier detection results of the Isolation Forest algorithm and 3-sigma principle,the accuracy of the CLOF detection results is increased,and the amount of data calculation is significantly reduced.

关键词： temperature data outlier detection ethylene cracker furnace clustering data clipping LOF

Genus two correlation functions in CFTs with TT deformation

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Science China(Physics,Mechanics & Astronomy) 2023年第5期66卷 106-119页

作者： song he Yun-Ze Li Center for Theoretical Physics and College of Physics Jilin UniversityChangchun 130012China Max Planck Institute for Gravitational Physics(Albert Einstein Institute) Am Mühlenberg 114476 GolmGermany

Since the definition of TT deformation in the curved Riemann surface is obstructive in the literature,we propose a way to do the deformation in the genus two Riemann surfaces by sewing prescription.We construct the correlation functions of conformal field theories(CFTs)on genus two Riemann surfaces with the TT deformation in terms of the perturbative CFT approach.Thanks to sewing construction to form higher genus Riemann surfaces from lower genus ones and conformal symmetry,we systematically obtain the first-order TT correction to the genus two correlation functions in the TT deformed CFTs,e.g.,partition function and one/higher-point correlation functions.

关键词： conformal field theory gauge/gravity duality TT deformation higher genus correlation function

A review of mobile robot motion planning methods:from classical motion planning workflows to reinforcement learning-based architectures

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Journal of Systems Engineering and Electronics 2023年第2期34卷 439-459页

作者： DONG Lu he Zichen song Chunwei SUN Changyin School of Cyber Science and Engineering Southeast UniversityNanjing 211189China Shanghai Institute of Intelligent Science and Technology Tongji UniversityShanghai 201804China College of Electronics and Information Engineering Tongji UniversityShanghai 201804China School of Automation Southeast UniversityNanjing 210096China

Motion planning is critical to realize the autonomous operation of mobile robots.As the complexity and randomness of robot application scenarios increase,the planning capability of the classical hierarchical motion planners is challenged.With the development of machine learning,the deep reinforcement learning(DRL)-based motion planner has gradually become a research hotspot due to its several advantageous feature.The DRL-based motion planner is model-free and does not rely on the prior structured map.Most importantly,the DRL-based motion planner achieves the unification of the global planner and the local planner.In this paper,we provide a systematic review of various motion planning methods.Firstly,we summarize the representative and state-of-the-art works for each submodule of the classical motion planning architecture and analyze their performance features.Then,we concentrate on summarizing reinforcement learning(RL)-based motion planning approaches,including motion planners combined with RL improvements,map-free RL-based motion planners,and multi-robot cooperative planning methods.Finally,we analyze the urgent challenges faced by these mainstream RLbased motion planners in detail,review some state-of-the-art works for these issues,and propose suggestions for future research.

关键词： mobile robot reinforcement learning(RL) motion planning multi-robot cooperative planning

Reduction potential of the energy penalty for CO_(2) capture in CCS

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Frontiers in Energy 2023年第3期17卷 390-399页

作者： Yawen ZheNG Lin GAO song he Hongguang JIN Laboratory of Integrated Energy System and Renewable Energy Institute of Engineering ThermophysicsChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China

CO_(2) capture and storage(CCS)has been acknowledged as an essential part of a portfolio of technologies that are required to achieve cost-effective long-term CO_(2) mitigation.However,the development progress of CCS technologies is far behind the targets set by roadmaps,and engineering practices do not lead to commercial deployment.One of the crucial reasons for this delay lies in the unaffordable penalty caused by CO_(2) capture,even though the technology has been commonly recognized as achievable.From the aspects of separation and capture technology innovation,the potential and promising direction for solving this problem were analyzed,and correspondingly,the possible path for deployment of CCS in China was discussed.Under the carbon neutral target recently proposed by the Chinese government,the role of CCS and the key milestones for deployment were indicated.

关键词： CO_(2)capture and storage(CCS) CO_(2)separation energy penalty

Coordination states of metal ions in molten salts and their characterization methods

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International Journal of Minerals,Metallurgy and Materials 2023年第7期30卷 1261-1277页

作者： Xin song Shaolong Li Shanshan Liu Yong Fan Jilin he Jianxun song School of Material Science and Engineering Zhengzhou UniversityZhengzhou 450001China Zhongyuan Critical Metals Laboratory Zhengzhou UniversityZhengzhou 450001China College of Resource and Environmental Engineering Wuhan University of Science and TechnologyWuhan 430081China

The macroscopic characteristics of molten salts are governed by their microstructures.Research on the structures of molten salts provides the foundation for a full understanding of the physicochemical properties of molten salts as well as a deeper analysis of the microscopic electrolysis process in molten salts.Information about the microstructure of matter can be obtained with the help of several speculative and experimental procedures.In this review,the advantages and disadvantages of the various test procedures used to determine the microstructures of molten salts are compared.The typical coordination configurations of metal ions in molten salt systems are also summarized.Furthermore,the impact of temperature,anions,cations,and metal oxides(O2-)on the structures of molten salts is discussed in detail.The accuracy and completeness of the information on molten salt structures need to be investigated by the integration of multiple methods and interdisciplinary fields.Information on the microstructure and coordination of molten salts deepens the understanding of the elementary elements of the microstructure of matter.This paper,which is based on the review of the coordination states of metal ions in molten salts,is hoped to inspire researchers to explore the inter-relationship between the microstructure and macroscopic properties of materials.

关键词： microstructure salts coordination