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控制理论与应用（英文版） 2008年第1期6卷 2-10页

作者： Linying XIANG zhongxin liu Zengqiang CHEN Fei CHEN Ge GUO Zhuzhi YUAN Department of Automation Nankai University Tianjin 300071 China Institute of Systems and Control School of Automation and Electric Engineering Dalian Maritime University Dalian Liaoning 116026 China

The stabilization properties of various typical complex dynamical networks composed of chaotic nodes are theoretically investigated and numerically simulated in detail. Some local stability properties of such pinned networks are derived and the valid stability regions are estimated based on eigenvalue analysis. Numerical simulations of such networks are given to explain why significantly less local controllers are needed by the specifically pinning scheme, which pins the most highly connected nodes in scale-free networks, than that required by the randomly pinning scheme. Also, it is explained why there is no significant difference between the two schemes for controlling random-graph networks and small-world networks.

关键词： Complex dynamical network Specifically pinning control Randomly pinning control Lorenz system Chaotic

Relations between structural properties and synchronizability on local world dynamical networks

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Progress in Natural Science:Materials International 2007年第8期17卷 956-961页

作者： Sun Shiwen~(**) liu zhongxin Chen Zengqiang Yuan Zhuzhi (Department of Automation,Nankai University,Tianjin 300071,China) [a]Department of Automation Nankai University Tianjin China

In this paper,the effects of various structural properties on the synchronization of coupled oscillators with local-world coupling configurations are *** is found that for local world networks,the larger heterogeneity of the degree distribution,the enhanced interconnection of nodes,and the increased clustering do not improve the synchronizability of dynamical *** the con- trary,the increase of the maximum betweenness centrality appears to be responsible for the decrease of the synchronizability.

关键词： complex dynamical network local-world evolving model synchronizability structural properties betweenness centrality

Sampled data based containment control of second-order multi-agent systems under intermittent communications

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Frontiers of Information Technology & Electronic Engineering 2021年第8期22卷 1059-1067页

作者： Fuyong WANG zhongxin liu Zengqiang CHEN Department of Automation College of Artificial IntelligenceNankai UniversityTianjin 300350China Tianjin Key Laboratory of Intelligent Robotics College of Artificial IntelligenceNankai UniversityTianjin 300350China

This paper studies the sampled data based containment control problem of second-order multi-agent systems with intermittent communications,where velocity measurements for each agent are unavailable.A novel controller for second-order containment is put forward via intermittent sampled position data *** necessary and sufficient conditions are derived to achieve intermittent sampled containment control by means of analyzing the relationship among control gains,eigenvalues of the Laplacian matrix,the sampling period,and the communication ***,several simulation examples are used to testify the correctness and effectiveness of the theoretical results.

关键词： Containment control Second-order multi-agent system Sampled position data Intermittent communication Communication width

Epidemic spreading behavior with time delay on local-world evolving networks

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Frontiers of Electrical and Electronic Engineering in China 2008年第2期3卷 129-135页

作者： Chengyi XIA zhongxin liu Zengqiang CHEN Shiwen SUN Zhuzhi YUAN Department of Automation Nankai UniversityTianjin 300071China School of Computer Science and Technology Tianjin University of TechnologyTianjin 300191China

An improved susceptible-infected-susceptible(SIS)model in the local-world evolving network model is presented to study the epidemic spreading behavior with time delay,which is added into the infected *** local-world evolving model displays a transition from the exponential network to the scale-free network with respect to the degree *** typical delay regimes,i.e.,uniform and degree-dependent delays are incorporated into the SIS epidemic model to investigate the epidemic infection processes in the local-world net-work *** results indicate that the infection delay will promote the epidemic outbreaks,increase the prevalence and reduce the critical threshold of epidemic *** is also found that local-world size M will considerably influence the epidemic spreading behavior with time delay in the local-world network through large-scale numerical *** results are also of relevance to fight epidemic outbreaks.

关键词： epidemic spreading time delay local-world model complex networks infection dynamics

Nitrogen-doped microporous graphite-enhanced copper plasmonic effect for solar evaporation

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Carbon Energy 2024年第3期6卷 215-223页

作者： Xintao Wu Chengcheng Li Ziqi Zhang Yang Cao Jieqiong Wang Xinlong Tian zhongxin liu Yijun Shen Mingxin Zhang Wei Huang School of Marine Science and Engineering School of Chemistry and Chemical EngineeringHainan UniversityHaikouHainanChina Key Laboratory of Child Cognition and Behavior Development of Hainan Province Qiongtai Normal UniversityHaikouHainanChina

Water scarcity is a global challenge,and solar evaporation technology offers a promising and eco-friendly solution for freshwater *** conversion materials(PCMs)are crucial for solar *** photothermal conversion efficiency and reducing water evaporation enthalpy are the two key strategies for the designing of *** desired PCMs that combine both of these properties remain a challenging task,even with the latest advancements in the ***,we developed copper nanoparticles(NPs)with different conjugated nitrogen-doped microporous carbon coatings(Cu@C–N)as *** microporous carbon enveloping layer provides a highly efficient pathway for water transport and a nanoconfined environment that protects Cu NPs and facilitates the evaporation of water clusters,reducing the enthalpy of water ***,the conjugated nitrogen nodes form strong metal-organic coordination bonds with the surface of copper NPs,acting as an energy bridge to achieve rapid energy transfer and provide high solar-to-vapor conversion *** Cu@C–N exhibited up to 89.4%solar-to-vapor conversion efficiency and an evaporation rate of 1.94 kgm^(−2) h^(−1) under one sun irradiation,outperforming conventional PCMs,including carbon-based materials and semiconductor *** findings offer an efficient design scheme for high-performance PCMs essential for solar evaporators to address global water scarcity.

关键词： nanoconfinement photothermal conversion materials plasmonic resonance seawater desalination solar evaporation

Rational design ternary platinum based electrocatalysts for effective methanol oxidation reaction

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Journal of Energy Chemistry 2022年第7期31卷 230-235,I0007页

作者： Hao Tian Daoxiong Wu Jing Li Junming Luo Chunman Jia zhongxin liu Wei Huang Qi Chen Chong Michael Shim Peilin Deng Yijun Shen Xinlong Tian State Key Laboratory of Marine Resource Utilization in South China Sea Hainan Provincial Key Lab of Fine ChemistrySchool of Chemical Engineering and TechnologyHainan UniversityHaikou 570228HainanChina

Exploring effective, durable, and affordable electrocatalysts of methanol oxidation reaction(MOR) is of vital significance for the industrial application of direct methanol fuel cells. Herein, an efficient, general,and expandable method is developed to synthesis two-dimensional(2D) ternary Pt Bi M nanoplates(NPLs), in which various M(Co, Ni, Cu, Zn, Sn) is severed as the third component to the binary Pt Bi system. The MOR performance of Pt Bi M NPLs is entirely investigated, demonstrating that both the MOR activity and durability is enhanced with the introduction of the additional composition. Pt3Bi3Zn NPLs shows much higher MOR activity and stability than that of the Pt Bi counterparts, not to mention the current advanced Pt Ru/C and Pt/C catalysts. The prominent performances are attributed to the modulated electronic structure of the surface Pt in Pt Bi NPLs by the addition of Zn, resulting in a weakened affination between Pt and the adsorbed poisoning species(mainly CO) compared with Pt Bi NPLs, verified by density functional theory(DFT) calculations. In addition, the absorbed OH can be generated on the surface of Zn atom due to its favorable water activation properties, thus the CO removal on the adjacent Pt atoms is accelerated, further leading to a high activity and anti-poisoning performance of the resulting Pt_(3)Bi_(3)Zn catalyst. This work provides new insights and robust strategy for highly efficient MOR electrocatalyst with extraordinary anti-poisoning performance and stability.

关键词： Fuel cells Ternary nanoplates Durability Methanol oxidation reaction Anti-poisoning

One-dimensional PtFe hollow nanochains for the efficient oxygen reduction reaction

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Carbon Energy 2022年第6期4卷 1003-1010页

作者： Peng Rao Junming Luo Jing Li Wei Huang Wei Sun Qi Chen Chunman Jia zhongxin liu Peilin Deng Yijun Shen Xinlong Tian State Key Laboratory of Marine Resource Utilization in South China Sea Hainan Provincial Key Lab of Fine ChemistrySchool of Chemical Engineering and TechnologyHainan UniversityHaikouChina

Integration of electronic and strain effects with tailored structures is significant to tuning the electrocatalytic activity and stability of the electrocatalysts for the oxygen reduction reaction(ORR).In this study,onedimensional PtFe hollow nanochains are synthesized by a facile and effective method,which exhibit a highly open and porous *** modulated electronic and strain effects of Pt atoms are verified by extensive structural characterizations,and the mass and specific activities of the prepared catalyst are roughly 7.45 and 12.44 times higher than those of the commercial Pt/C catalyst,***,the catalyst demonstrates robust performance with negligible activity decay after an accelerated durability test for 30,000 *** high activity of the catalyst is probably due to the optimized absorption affinity of Pt-O accelerating the reaction kinetics induced by the cooperation of Fe atoms as well as the unique hollow and curved *** study provides new insights into the rational design of high-performance ORR catalysts with considerable durability.

关键词： electrocatalysts hollow nanochains one-dimensional oxygen reduction reaction zinc-air battery

Effect of the Structure of Cations and Anions of Ionic Liquids on Separation of Aromatics from Hydrocarbon Mixtures

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Petroleum Science 2006年第3期3卷 73-78页

作者： liu Yansheng Zhang zhongxin Zhang Guofu liu Zhichang Hu Yufeng Shi Quan Ji Dejun Faculty of Chemical Science and Engineering China University of Petroleum Beijing 102249 China

The effects of the structure of typical cations and anions of ionic liquids on the separation of benzene and toluene from aromatic/paraffin mixtures were studied. The .results showed that the corresponding separation factors were considerably larger than those of the traditional solvents （Benzene＋Hexane＋sulfolane）, and that the ionic liquids could be used as novel solvents for the separation of aromatics from hydrocarbon mixtures. The key parameters governing the ability of ionic liquids for separating aromatics from hydrocarbon sources were investigated. It was found that the effectiveness of the ionic liquids, based on the same anion, changed in the cation order of [BIqu]^＋〈 [BPy]^＋〈 [BMIM]^＋. The selectivity of the ionic liquid toward aromatics decreased apparently with the increasing length of the substituted alkyl chain of its cationic head ring. The separation factors, based on the same cation, changed in the anion order of [Tf2N]^-〈[PF6]^-〈[BF4]^-〈[C2H5SO4]^-. The solubilities of the aromatics were greater in the ionic liquids based on the former three anions than that in the ionic liquids involving [C2H5SO4]^-.

关键词： Aromatic and aliphatic compounds ionic liquids extractive solvents

Manifold alignment using discrete surface Ricci flow

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CAAI Transactions on Intelligence Technology 2016年第3期1卷 285-292页

作者： zhongxin liu Wenmin Wang Qun Jin School of Electronic and Computer Engineering Shenzhen Graduate School Peking University China Faculty of Human Sciences Waseda University Japan

Manifold alignment is useful to extract the shared latent structure among multiple data sets and the similarity among different datasets. As many kinds of real world data can be analyzed using low dimensional representations, manifold alignment algorithms can be used in a wide range of applications, such as data mining. In this paper, we propose a three-stage approach to manifold alignment using discrete surface Ricci flow. Our approach transforms the original intrinsic manifolds to hyper spheres using confonnal mapping in the first stage, and then zooms these hyper spheres into the same scale and aligns them in the following stages. We describe in details about our algorithm, its theoretical principles, our experimental results, and the comparison to previous alignment methods. To prove the effectiveness of our algorithm, three kinds of experiments are presented, including a toy dataset, one containing parallel corpus of parliament proceedings and another containing both images and texts. With these experiments, the latent utility in discovering the similarity among different kinds of data sets can be demonstrated, whether within the same kind of data or across different kinds of modals of data.

关键词： Cross-lingual retrieval Cross-media retrieval Dimensionality reduction Manifold alignment