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IEEE/CAA Journal of Automatica Sinica 2024年第8期11卷 1865-1876页

作者： Weiwei Sun Xinci Gao Lusong Ding Xiangyu Chen the Institute of Automation Qufu Normal University

This paper is aimed at the distributed fault estimation issue associated with the potential loss of actuator efficiency for a type of discrete-time nonlinear systems with sensor saturation. For the distributed estimation structure under consideration,an estimation center is not necessary, and the estimator derives its information from itself and neighboring nodes, which fuses the state vector and the measurement vector. In an effort to cut down data conflicts in communication networks, the stochastic communication protocol(SCP) is employed so that the output signals from sensors can be selected. Additionally, a recursive security estimator scheme is created since attackers randomly inject malicious signals into the selected data. On this basis, sufficient conditions for a fault estimator with less conservatism are presented which ensure an upper bound of the estimation error covariance and the mean-square exponential boundedness of the estimating error. Finally, a numerical example is used to show the reliability and effectiveness of the considered distributed estimation algorithm.

关键词： Actuators Sufficient conditions Protocols Upper bound Estimation Vectors Security

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Event-triggered adaptive output feedback control for hyperbolic PDEs: swapping-based design

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Science China(Information Sciences) 2024年第5期67卷 327-328页

作者： Chunting JI Zhengqiang ZHANG Xue-Jun XIE School of Engineering Qufu Normal University Institute of Automation Qufu Normal University

Partial differential equations(PDEs) characterize transport phenomena and fluid flow, and common cases include heat exchangers and road traffic [1]. Recently, scholars have become enthusiastic about event-triggered control(ETC) of hyperbolic PDEs, primarily because it can help conserve computing and communication resources. For example,Ref. [2] presented an output feedback ETC scheme for 2 × 2hyperbolic PDEs.

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Small-sized Ni-Co/Mo_(2)C/Co_(6)Mo_(6)C_(2)@C for efficient alkaline and acidic hydrogen evolution reaction by an anchoring calcination strategy

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Frontiers of Chemical Science and Engineering 2024年第5期18卷 95-103页

作者： Jianxia Gu Ying Zhu Haiyan Zheng Chunyi Sun Zhongmin Su Department of Chemistry Xinzhou Normal UniversityXinzhou 034000China School of Chemistry Northeast Normal UniversityChangchun 130024China

A novel,cheap and highly efficient Ni-Co/Mo_(2)C/Co_(6)Mo_(6)C_(2)@C nanocomposite has been successfully constructed through simple one-step carbonization method in a nitrogen *** in the precursor can effectively anchor molybdenum-based Keggin-type polyoxometallate and NiCo-layered double hydroxide through electrostatic and coordination interactions,which avoids the aggregation of catalyst particles during the pyrolysis *** optimization,the obtained Ni-Co/Mo_(2)C/Co_(6)Mo_(6)C_(2)@C possesses small size(3-8 nm),large specific surface area and hierarchical pore *** importantly,Ni-Co/Mo_(2)C/Co_(6)Mo_(6)C_(2)@C presents remarkable hydrogen evolution reaction activity with low overpotentials in 0.5 mol·L^(-1)H_(2)SO_(4)(102.3 mV)and 1 mol·L^(-1)KOH(95 mV)to afford the current density of 10 mA·cm^(-2),as well as small Tafel slopes of 82.49 and 99.92 mV·dec^(-1),***,this catalyst also shows outstanding stability for 12 h without a significant change in current *** excellent catalytic performance of Ni-Co/Mo_(2)C/Co_(6)Mo_(6)C_(2)@C can put down to the synergistic effect between multiple components and the small size of the *** work provides unique insights into the preparation of efficient transition metal-based catalysts for HER.

关键词： polyoxometallates layered double hydroxide transition metal-based electrocatalysts hydrogen evolution reaction

Boosted sustained-release with iron-based MOF-derived mesoporouscarbon-spheres as a nitroimidazole drugs carrier

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Particuology 2024年第3期86卷 269-280页

作者： Danping Wu Jiaying Zou Junyi Chen Yan Li Na Ma Wei Dai College of Chemistry and Materials Science Zhejiang Normal UniversityJinhua321004China College of Life Sciences Zhejiang Normal UniversityJinhua321004China College of Geography and Environmental Sciences Zhejiang Normal UniversityJinhua321004China

Metal-organic framework(MoF)with a buildable internal structure has aroused great interest focus as self-sacrificing precursors of porous carbon(PC).However,as a drug carrier,the MOF-derived PC developed thus far are generally composed of irregular powder shape due to their crystalline nature,which consequently causing the cerebral infarction,cerebral thrombosis,and other blood *** this article,we propose a novel approach to constructing amorphous carbon microspheres(AcMs)by dis-torting the topological network through hydrothermal treatment precursors of MIL-101(Fe).Then,a distinctive MIL-101(Fe)-derived spherical porous carbons(MSPC)is achieved through high temperature calcination toward *** of the glucose initial concentration and hydrothermal treatment time on the sphericity of the as-prepared mesoporous MsPC were investigated in *** the loading capacities and sustained-release performances of nitroimidazole drugs over MsPC through simulation internal environment of human body at different pH values was systematically *** nitro-imidazole drugs loading rate and release time of MsPC are 10% and 17 h under preferred ***,the MSPC exhibited very low toxicity on Hela cells and 293T cells at the concentrations tested(10-800μg mL^(-1)).This study,therefore,supports the potential of the mesoporous carbon spheres as a carrierfor nitroimidazole drug delivery.

关键词： Ornidazole Metronidazole Carbon spheres Sustained-release performance Biocompatibility

Probing the peripheral self-generated magnetic field distribution in laser-plasma magnetic reconnection with Martin-Puplett interferometer polarimeter

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Chinese Physics B 2024年第4期33卷 129-134页

作者：张雅芃姚嘉文刘正东马作霖仲佳勇 Department of Astronomy Beijing Normal UniversityBeijing 100875China Institute for Frontiers in Astronomy and Astrophysics Beijing Normal UniversityBeijing 102206China

Magnetic reconnection of the self-generated magnetic fields in laser-plasma interaction is an important laboratory method for modeling high-energy density astronomical and astrophysical *** use the Martin-Puplett interferometer(MPI)polarimeter to probe the peripheral magnetic fields generated in the common magnetic reconnection configuration,two separated coplanar plane targets,in laser-target *** introduce a new method that can obtain polarization information from the interference pattern instead of the sinusoidal function fitting of the intensity.A bidirectional magnetic field is observed from the side view,which is consistent with the magneto-hydro-dynamical(MHD)simulation results of self-generated magnetic field *** find that the cancellation of reverse magnetic fields after averaging and integration along the observing direction could reduce the magnetic field strength by one to two orders of *** indicates that imaging resolution can significantly affect the accuracy of measured magnetic field strength.

关键词： laser-plasma experiment polarimeter self-generated magnetic field magnetic reconnection

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Nonlocal coherence harvesting from quantum vacuum

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Communications in Theoretical Physics 2024年第07期76卷 46-53页

作者： Rui-Di Wang Shu-Min Wu Xiao-Li Huang Department of Physics Liaoning Normal University

It is well known that nonlocal coherence reflects nonclassical correlations better than quantum entanglement. Here, we analyze nonlocal coherence harvesting from the quantum vacuum to particle detectors adiabatically interacting with a quantum scalar field in Minkowski *** find that the harvesting-achievable separation range of nonlocal coherence is larger than that of quantum entanglement. As the energy gap grows sufficiently large, the detectors harvest less quantum coherence, while the detectors could extract more quantum entanglement from the vacuum state. Compared with the linear configuration and the scalene configuration, we should choose the model of equilateral triangle configuration to harvest tripartite coherence from the vacuum. Finally, we find a monogamous relationship, which means that tripartite l1-norm of coherence is essentially bipartite types.

关键词： monogamous relationship nonlocal coherence quantum vacuum

Transition metal clusters with precise numbers of atoms anchored on graphdiyne as multifunctional electrocatalysts for OER/ORR/HER:a computational study

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Rare Metals 2024年第7期43卷 3107-3117页

作者： Xin-Yang Liu Jing-Wei Liu Gang Li Jing-Xiang Zhao College of Chemistry and Chemical Engineering Harbin Normal University

Subnanometer metal clusters play an increasingly important role in heterogeneous catalysis due to their high catalytic activity and *** this work,by means of the density functional theory（DFT） calculations,the catalytic activities of transition metal clusters with precise numbers of atoms supported on graphdiyne(TM1-4@GDY,TM=V,Cr,Mn,Fe,Co,Ni,Cu,Ru,Rh,Pd,Ir,Pt) were investigated for oxygen evolution reactions（OER）,oxygen reduction reactions（ORR） and hydrogen evolution reactions（HER）.The computed results reveal that the Pd2,Pd4and Pt1anchored graphdiyne can serve as trifunctional catalysts for OER/ORR/HER with the overpotentials of 0.49/0.37/0.06,0.45/0.33/0.12 and 0.37/0.43/0.01 V,respectively,while Pd1and Pt2@graphdiyne can exhibit excellent catalytic performance for water splitting（OER/HER） with the overpotentials of 0.55/0.17 and 0.43/0.03 *** addition,Ni1and Pd3anchored GDY can perform as bifunctional catalysts for metal-air cells（OER/ORR） and fuels cells（ORR/HER） with the overpotentials of 0.34/0.32 and 0.42/0.04 V,***,by precisely controlling the numbers of atoms in clusters,the TM1-4anchored graphdiyne can serve as promising multifunctional electrocatalysts for OER/ORR/HER,which may provide an instructive strategy to design catalysts for the energy conversation and storage devices.

关键词： Density functional theory Graphdiyne Single-cluster catalysts Multifunctional electrocatalysts Overpotential

Anomalous time-reversal symmetric non-Hermitian systems

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Chinese Physics B 2024年第6期33卷 162-166页

作者：易益妃 Sichuan normal university Chengdu 610066China

The conditions for the emergence of the non-Hermitian skin effect, as a unique physical response of non-Hermitian systems, have now become one of the hot research topics. In this paper, we study the novel physical responses of nonHermitian systems with anomalous time-reversal symmetry, in both one dimension and two dimensions. Specifically, we focus on whether the systems will exhibit a non-Hermitian skin effect. We employ the theory of generalized Brillouin zone and also numerical methods to show that the anomalous time-reversal symmetry can prevent the skin effect in onedimensional non-Hermitian systems, but is unable to exert the same effectiveness in two-dimensional cases.

关键词： skin effect symmetry non-Hermitian systems

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Highly reversible Zn anode enabled by anticatalytic carbon layer with suppressed hydrogen evolution

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Rare Metals 2024年第7期43卷 3044-3054页

作者： Wen-Duo Zhang Chuang Sun Yu-Xuan Zhu Feng Gao Chao Lai School of Chemistry and Materials Science Jiangsu Normal University

Aqueous zinc-ion batteries（AZIBs） have emerged as a promising high-efficiency energy storage system due to the high energy density,low-cost and environmental ***,the practical application of AZIBs is severely restricted by the challenges faced by the Zn anode,which include uncontrollable dendrite growth,corrosion and hydrogen evolution ***,a simple and convenient physical vapor deposition（PVD）method is reported for fabricating uniform graphite as a protection layer on the surface of Zn *** high conductivity graphite layer on Zn anode（denoted as Zn@C） not only benefits the uniform distribution of the electric field,but also provides numerous Zn nucleation sites to regulate and navigate Zn-ion stripping/plating ***,the graphite layer with a poor catalytic activity endows the Zn@C anode with a highly suppressed hydrogen ***,a hydrogen and dendrite free anode is achieved with artificial anticatalytic carbon layer on Zn anode,exhibiting a high reversibility and excellent cycling stability over 2600 h at the current density of 5 mA·cm-2with a capacity of 2.5 mAh·cm-2and longtime cycling stability for assembled full *** work strategically designs the properties of the artificial interface layer to effectively address various challenges simultaneously,which presents insights for the future development of high-performance rechargeable AZIBs.

关键词： Zn metal anode Artificial anticatalytic layer Hydrogen suppression Dendrite free

Study on Coded Permutation Entropy of Finite Length Gaussian White Noise Time Series

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Chinese Journal of Electronics 2024年第1期33卷 185-194页

作者： Huihui SUN Xiaofeng ZHANG School of Physics and Information Technology Shaanxi Normal University

As an extension of permutation entropy(PE), coded permutation entropy(CPE) improves the performance of PE by making a secondary division for ordinal patterns defined in PE. In this study, we provide an exploration of the statistical properties of CPE using a finite length Gaussian white noise time series theoretically. By means of the Taylor series expansion, the approximate expressions of the expected value and variance of CPE are deduced and the Cramér-Rao low bound(CRLB) is obtained to evaluate the performance of the CPE estimator. The results indicate that CPE is a biased estimator, but the bias only depends on relevant parameters of CPE and it can be easily corrected for an arbitrary time series. The variance of CPE is related to the encoding patterns distribution,and the value converges to the CRLB of the CPE estimator when the time series length is large enough. For a finitelength Gaussian white noise time series model, the predicted values can match well with the actual values, which further validates the statistic theory of CPE. Using the theoretical expressions of CPE, it is possible to better understand the behavior of CPE for most of the time series.

关键词： Time series analysis White noise Predictive models Taylor series Entropy Encoding Time measurement

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