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Stability analysis and stabilization of semi-Markov jump linear systems with unavailable sojourn-time information

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Science China(Information Sciences) 2024年第7期67卷 211-223页

作者： Xiaotai WU Yang tang Shuai mao Ying ZHAO School of Mathematics and Physics Anhui Polytechnic University Key Laboratory of Advanced Control and Optimization for Chemical Processes Ministry of EducationEast China University of Science and Technology

This study addresses the stability and stabilization problems of discrete-time semi-Markov jump linear systems(S-MJLSs) with unavailable sojourn-time information. The sojourn-time probability mass functions(S-TPMFs) of discrete-time semi-Markov chains are no longer confined to the geometric distribution, and it is difficult to obtain accurate and comprehensive information for S-TPMFs in practice. This is because S-TPMFs are usually deduced from the statistical characteristics according to the sampled-data, while adequate samples are often costly and time consuming. In this study, when the S-TPMFs for semi-Markov chains are assumed to be unavailable, the σ-error mean square stability is investigated for discrete-time S-MJLSs with some widely used assumptions; for semi-Markov chains, only the transition probability matrix of the embedded chain is used. In addition, the existence conditions of the effective controller are provided for closed-loop systems without using the information of S-TPMFs. Numerical examples are presented to illustrate the validity of the obtained theoretical results.

关键词： semi-Markov chain semi-Markov jump linear systems $\sigma$-error mean square stability unavailable sojourn-time information

Shape optimisation of basin insulator for DC gas insulated switchgear/gas insulated transmission lines based on artificial bee colony algorithm

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High Voltage 2024年第2期9卷 275-286页

作者： Yi Luo Shiyi mao Ju tang Zijun Pan Cheng Pan State Key Laboratory of Power Grid Environmental Protection School of Electrical Engineering and AutomationWuhan UniversityWuhanChina

The surface charge accumulation on the basin insulator is a particular problem in high-voltage direct current(HVDC)gas insulated switchgears(GIS)and gas insulated trans-mission lines(GIL),which restricts the development and application of extra/ultra high-voltage(EHV/UHV)*** surface charge distribution and anti-flashover performance are closely related to the insulator *** obtain the optimal basin insulator,a shape optimisation model based on artificial bee colony algorithm was established,and the minimisation objective functions based on capacitive(initial)electric field distribution and resistive(steady-state)electric field distribution were respectively *** optimisation results of the two objective functions were calculated,and the electric field and charge distribution on the surface of the insulator before and after optimisation were evaluated and compared using the simulation *** results indicated that the optimisation based on the capacitive electric field can significantly inhibit the surface charge accumulation,and the optimised insulator can significantly reduce the surface normal electric field and make the distribution of the tangential electric field more uniform,and the maximum tangential electric field can be reduced by 10%;the optimisation based on resistive electric field can achieve similar results,but requires more computational *** on the results,the‘anti-charge’basin insulator structure suitable for the DC field was given.

关键词： insulator artificial charge

Magnetically controllable multimode interference in topological photonic crystals

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Light(Science & Applications) 2024年第5期13卷 998-1005页

作者： Weiyuan tang Mudi Wang Shaojie Ma Che ting Chan Shuang Zhang New Cornerstone Science Laboratory Department of PhysicsThe University of Hong KongHong KongChina. Department of Physics The Hong Kong University of Science and TechnologyHong KongChina. Department of Optical Science and Engineering Fudan UniversityShanghai 200433China

Topological photonic insulators show promise for applications in compact integrated photonic circuits due to their ability to transport light robustly through sharp *** number of topological edge states relies on the difference between the bulk Chern numbers across the boundary,as dictated by the bulk edge *** interference among multiple topological edge modes in topological photonics systems may allow for controllable functionalities that are particularly desirable for constructing reconfigurable photonic *** this work,we demonstrate magnetically controllable multimode interference based on gyromagnetic topological photonic insulators that support two unidirectional edge modes with different *** successfully achieve controllable power splitting in experiments by engineering multimode interference with the magnetic field intensity or the frequency of *** work demonstrates that manipulating the interference among multiple chiral edge modes can facilitate the advancement of highly efficient and adaptable microwave devices.

关键词： multimode controllable microwave

Effects of thawing-induced softening on fracture behaviors of frozen rock

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第3期16卷 979-989页

作者： ting Wang Hailiang Jia Qiang Sun Xianjun Tan Liyun tang College of Geology and Environment Xi’an University of Science and TechnologyXi’an710054China College of Architecture and Civil Engineering Xi’an University of Science and TechnologyXi’an710054China State Key Laboratory of Geomechanics and Geotechnical Engineering Institute of Rock and Soil MechanicsChinese Academy of SciencesWuhan430064China

Due to the presence of ice and unfrozen water in pores of frozen rock,the rock fracture behaviors are susceptible to *** this study,the potential thawing-induced softening effects on the fracture behaviors of frozen rock is evaluated by testing the tension fracture toughness(KIC)of frozen rock at different temperatures(i.e.-20℃,-15℃,-12℃,-10℃,-8℃,-6℃,-4℃,-2℃,and 0℃).Acoustic emission(AE)and digital image correlation(DIC)methods are utilized to analyze the microcrack propagation during *** melting of pore ice is measured using nuclear magnetic resonance(NMR)*** results indicate that:(1)The KIC of frozen rock decreases moderately between-20℃ and-4℃,and rapidly between-4℃ and 0℃.(2)At-20℃ to-4℃,the fracturing process,deduced from the DIC results at the notch tip,exhibits three stages:elastic deformation,microcrack propagation and microcrack ***,at-4℃e0℃,only the latter two stages are observed.(3)At-4℃e0℃,the AE activities during fracturing are less than that at-20℃ to-4℃,while more small events are reported.(4)The NMR results demonstrate a reverse variation trend in pore ice content with increasing temperature,that is,a moderate decrease is followed by a sharp decrease and-4℃ is exactly the critical ***,we interpret the thawing-induced softening effect by linking the evolution in microscopic structure of frozen rock with its macroscopic fracture behaviors as follow:from-20℃ to-4℃,the thickening of the unfrozen water film diminishes the cementation strength between ice and rock skeleton,leading to the decrease in fracture ***-4℃ to 0℃,the cementation effect of ice almost vanishes,and the filling effect of pore ice is reduced significantly,which facilitates microcrack propagation and thus the easier fracture of frozen rocks.

关键词： Frozen sandstone Different thawing temperature Fracture toughness Microcrack propagation process Unfrozen water content

Li_(2)ZnTi_(3)O_(8)as the host–separator modifier with efficient polysulfides trapping and fast Li^(+)diffusion for lithium-sulfur batteries

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Nano Research 2024年第7期17卷 6087-6094页

作者： mao Qian Yakun tang Lang Liu Yue Zhang Xiaohui Li JiaJia Chen State Key Laboratory of Chemistry and Utilization of Carbon Based Energy Resources Xinjiang UniversityUrumqi 830017China State Key Laboratory of Physical Chemistry of Solid Surfaces Xiamen UniversityXiamen 361005China

The diffusion and loss of lithium polysulfides(LiPSs)in lithium-sulfur batteries(LSBs)reduce the sulfur utilization rate and the catalytic conversion efficiency of sulfur species,resulting in early battery ***_(2)ZnTi_(3)O_(8)(LZTO),characterized by its stable spinel structure,exhibits high Li+conductivity and holds great potential as an effective adsorbent for *** study proposes a collaborative design concept of LZTO host–separator modifier,which offers a complementary and matching approach in the cathode side,effectively addressing the challenges associated with dissolution and inadequate conversion of *** functional theory(DFT)calculation substantiates the pronounced chemical affinity of LZTO towards *** importantly,the high efficiency ion transport channels are achieved in separator coating due to the presence of the LZTO ***,the catalytic efficacy of LZTO is validated through meticulous analysis of symmetric batteries and Tafel ***,the LZTO host–separator modifier-based cell displays satisfactory rate capability(1449 and 1166 mAh·g^(−1)at 0.1 and 0.5 C)and an impressively capacity(606 mAh·g^(−1)after 500 cycles at 1 C).The coordinated strategy of host–separator modifier is supposed to have wide applications in LSBs.

关键词： Li_(2)ZnTi_(3)O_(8) lithium-sulfur batteries host-separator modifier catalytic conversion diffusion and loss of LiPSs

Evaluating the relative importance of predictors in Generalized Additive Models using the *** R package

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Plant Diversity 2024年第4期46卷 542-546页

作者： Jiangshan Lai Jing tang tingyuan Li Aiying Zhang Lingfeng mao College of Ecology and Environment Nanjing Forestry UniversityNanjing210037China Research Center of Quantitative Ecology Nanjing Forestry UniversityNanjing 210037China University of Chinese Academy of Sciences Beijing100049China Guangzhou Climate and Agro-meteorology Center Guangzhou 511430China Guangdong Ecological Meteorological Center Guangzhou 510640China

Generalized Additive Models(GAMs)are widely employed in ecological research,serving as a powerful tool for ecologists to explore complex nonlinear relationships between a response variable and ***,evaluating the relative importance of predictors with concurvity(analogous to collinearity)on response variables in GAMs remains a *** address this challenge,we developed an R package named *** calculates individual R^(2) values for predictors,based on the concept of'average shared variance',a method previously introduced for multiple regression and canonical *** these individual R^(2)s,which add up to the overall R^(2),researchers can evaluate the relative importance of each predictor within *** illustrate the utility of the *** package by evaluating the relative importance of emission sources and meteorological factors in explaining ozone concentration variability in air quality data from London,*** believe that the *** package will improve the interpretation of results obtained from GAMs.

关键词： Average shared variance Coefficient of determination Commonality analysis GAMs Hierarchical partitioning Individual R^(2)

Two-dimensional bimetallic selenium-containing metal-organic frameworks and their calcinated derivatives as electrocatalysts for overall water splitting

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Frontiers in Energy 2024年第3期18卷 378-389页

作者： Zhao-ting SHANG tang-ming LI Bing-qian HU Min LIU Wang-ting LU Fan YU Yun ZHENG Key Laboratory of Optoelectronic Chemical Materials and Devices of Ministry of Education College of Optoelectronic Materials and TechnologyJianghan UniversityWuhan 430056China Institute of New Energy Materials and Engineering School of Materials Science and EngineeringFuzhou UniversityFuzhou 350108China Department of Chemical Engineering University of WaterlooWaterlooOntario N2L 3G1Canada

The use of two-dimensional(2D)layered metal-organic frameworks(MOFs)as self-sacrificial templates has been proven to be a successful method to create high-efficiency Selenium(Se)-containing electrocatalysts for overall water ***,two strategies are then utilized to introduce Se element into the Co–Fe MOF,one being the etching of as-prepared MOF by SeO_(2) solution,and the other,the replacing of SCN−with SeCN−as the construction *** electrochemical activity of the pristine 2D MOF and their calcinated derivatives for catalyzing the hydrogen evolution reaction(HER)and oxygen evolution reaction(OER)is evaluated and further *** is found that the effect of introducing Se on improving electrochemical catalytic activity is significant for the HER ***,the calcinated derivative in the replacing method exhibits an overpotential of 235 mV for HER and 270 mV for OER at a current density of 10 mA/*** comparing the two methods of introducing Se element into MOF,similar electrocatalytic activity can be achieved on the their calcinated *** high electrochemical performance of 2D CoFe-MOF derivatives may be resulted from the unique 2D hierarchical porous structure and strong synergistic effect between different components in the material.

关键词： 2D MOF selenium(Se)-containing materials hydrogen evolution reaction(HER) oxygen evolution reaction(OER)

Single Particle Colorimetric Acid Phosphatase Activity Assay with CeO_(2)-modified Gold Nanoparticles

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Chemical Research in Chinese Universities 2024年第2期40卷 320-325页

作者： ZHU tang Jiayao YUAN Xiang mao Guojiang WEI Lin XIAO Lehui Key Laboratory of Chemical Biology and Traditional Chinese Medicine Research National and Local Joint Engineering Laboratory for New Petrochemical Materials and Fine Utilization of ResourcesCollege of Chemistry and Chemical EngineeringHunan Normal UniversityChangsha410081P.R.China Henan Key Laboratory of Organic Functional Molecule and Drug Innovation Collaborative Innovation Center of Henan Province for Green Manufacturing of Fine ChemicalsKey Laboratory of Green Chemical Media and ReactionsMinistry of EducationSchool of Chemistry and Chemical EngineeringHenan Normal UniversityXinxiang453007P.R.China College of Chemistry and Chemical Engineering Central South UniversityChangsha410083P.R.China

Acid phosphatase(ACP)is a ubiquitous phosphatase in living *** abnormal variation of ACP is related to various ***,we propose a colorimetric method based on CeO_(2)-modified gold core shell nanoparticles(Au@CeO_(2)NPs)to analyze ACP activity with high sensitivity and *** this design,2-phospho-L-ascorbic acid trisodium salt(AAP)is dephosphorylated by ACP and produces reductive ascorbic acid(AA),which makes the CeO_(2)shell decomposition.A remarkable blue shift of localized surface plasmon resonance peak(LSPR,from yellow to green)along with the scattering intensity ratio changes from individual Au@CeO_(2)NPs are *** activity can be quantified by calculating the ratio changes of individual Au@CeO_(2)*** assay reveals limit of detection(LOD)of 0.044 mU/mL and the linear range of 0.05–5.0 mU/mL,which are much lower than most of spectroscopic measurements in bulk ***,the recovery measurements in real samples are satisfactory and the capacity for practical application is *** a consequence,Au@CeO_(2)NPs used in this assay will find new applications for the ultrasensitive detection of enzyme activity.

关键词： Single particle imaging Dark field Gold nanoparticle Enzyme activity Colorimetric detection

Cobalt-doped TiO_(2)@C hierarchical nanocomposites derived from Ti_(3)C_(2) MXene as cathodes for hybrid magnesium-lithium batteries

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Nano Research 2024年第1期17卷 253-261页

作者： Xiaohui Li Yakun tang Lang Liu Yue Zhang Yang Gao mao Qian Wenjie Ma State Key Laboratory of Chemistry and Utilization of Carbon Based Energy Resources College of ChemistryXinjiang UniversityUrumqi 830017China

TiO_(2)has been explored in hybrid magnesium-lithium batteries(HMLBs)due to the advantages of low self-discharge and small volume expansion during ion ***,how to improve the inherently low ionic and electrical conductivity of TiO_(2)is the problem that needs to be *** this work,a smart strategy is adopted to prepare cobalt-doped TiO_(2)@C(Co^(4+)-TiO_(2)@C)hierarchical nanocomposite derived from Co(II)(OH)n@*** with TiO_(2)@C(without cobalt doping),Co^(4+)-TiO_(2)@C shows the highest specific capacity(154.7 mAh·g^(-1)at 0.1 A·g^(-1)after 200 cycles)and extraordinary rate performance in *** excellent electrochemical performance of Co4+-TiO_(2)@C is ascribed to the synergistic effect of the hierarchical structure and *** experimental results and density functional theory(DFT)calculation reveal that the cobalt-doping has effectively improved the electronic conductivity and reduced the Li+migration *** work provides a new insight to design TiO_(2)-based cathode materials with high-performance in HMLBs.

关键词： Ti_(3)C_(2)MXene TiO_(2) hybrid magnesium-lithium batteries hierarchical structure cobalt-doping