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Acta Mechanica Sinica 2000年第3期16卷 223-239页

作者： D.C.wan g.w.wei Shanghai Univ Shanghai Inst Appl Math&MechShanghai 200072Peoples R China Natl Univ Singapore Dept Computat SciSingapore 119260Singapore

An efficient discrete singular convolution (DSC) method is introduced to the numerical solutions of incompressible Euler and Navier-Stokes equations with periodic boundary conditions. Two numerical tests of two-dimensional Navier-Stokes equations with periodic boundary conditions and Euler equations for doubly periodic shear layer flows are carried out by using the DSC method for spatial derivatives and fourth-order Runge-Kutta method for time advancement, respectively. The computational results show that the DSC method is efficient and robust for solving tho problems of incompressible flows, and has the potential of being extended to numerically solve much broader problems in fluid dynamics.

关键词： incompressible flows periodic boundary DSC method fourth-order Runge-Kutta method

Dynamic event-triggered data-driven iterative learning bipartite tracking control for nonlinear MASs with prescribed performance

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Science China(Information Sciences) 2025年第1期68卷 292-305页

作者： Tao SHI wei-wei CHE School of Mechatronic Engineering and Automation Shanghai University State Key Laboratory of Synthetical Automation for Process Industries Northeastern University College of Information Science and Engineering Northeastern University

This article proposes a distributed dynamic event-triggered data-driven iterative learning control(DET-DDILC)scheme under a predefined performance to tackle the bipartite tracking control problem for multiagent systems(MASs). An improved dynamic linearization technique is utilized to convert the nonlinear MASs into an iterative linear data model. First,a peer-to-peer mapping function is introduced to map the constrained distributed system output homeomorphism to an unconstrained one. In addition, a DET mechanism based on a time-iteration-varying function is devised to conserve network communication resources. Based on the unconstrained transformation and the designed DET mechanism, the DET-DDILC algorithm is devised to ensure that the bipartite tracking performance of MASs can be within the preset range. Finally, the effectiveness and feasibility of the designed control scheme are demonstrated via a simulation case by a comparison.

关键词： bipartite tracking control prescribed performance event-triggered iterative learning control multiagent systems

Modeling the potential distribution of Argentine shortfin squid in the southwest Atlantic Ocean

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Journal of Oceanology and Limnology 2025年第1期43卷 326-340页

作者： Hewei LIU wei YU College of Marine Living Resource Sciences and Management Shanghai Ocean UniversityShanghai 201306China National Engineering Research Center for Oceanic Fisheries Shanghai Ocean UniversityShanghai 201306China Key Laboratory of Sustainable Exploitation of Oceanic Fisheries Resources Ministry of EducationShanghai Ocean UniversityShanghai 201306China Key Laboratory of Oceanic Fisheries Exploration Ministry of Agriculture and Rural AffairsShanghai Ocean UniversityShanghai 201306China

The Argentine shortfin squid Illex argentinus is an economically important short-lived species widely distributed in the southwest Atlantic *** abundance and distribution of *** are associated with climate change and environmental *** potential distribution of *** was modeled with various environmental variables including sea surface temperature(SST),sea surface height(SSH),chlorophyll a,sea surface salinity(SSS),net primary productivity(NPP),mixed layer depth(MLD),eddy kinetic energy(EKE),and photosynthetically active radiation(PAR)using the maximum entropy(MaxEnt)approach during the peak fishing seasons(January–April).The habitat suitability index(HSI)was defined as the probability of species emergence from the MaxEnt model and the area of HSI≥0.6 was regarded as *** indicate that the predicted habitat correlated with the actual fishing position,with similar trends in the percentages of suitable habitats and catch per unit effort(CPUE)of *** from January to ***,SST,SSH,PAR,and MLD were identified critical environmental variables for the distribution of *** addition,the median of preferred ranges of the critical environmental variables were concentrated within the suitable habitats of *** Area under the Receiver Operating Characteristic Curve(AUC)was greater than 0.96 for all four *** in latitudinal and longitudinal gravity centers(LATg and LONg)of fishing effort were consistent with latitudinal and longitudinal gravity centers(LATg_H and LONg_H)of the *** findings suggest that the MaxEnt model is an effective tool to predict the potential distribution of ***,SST,SSH,PAR,and MLD should be given with more extensive attention in predicting the potential distribution of ***,as they are important environmental indicators that can help decision-makers search for the fishing ground of *** in the Southwest Atlantic.

关键词： Illex argentinus maximum entropy model potential distribution oceanographic environmental condition

Solar cycles during the seventeenth century revealed by equatorial aurora records

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Earth and Planetary Physics 2025年第1期9卷 182-187页

作者： Yong wei LiMei Yan Key Laboratory of Earth and Planetary Physics Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China College of Earth and Planetary Sciences University of Chinese Academy of SciencesBeijing 100049China

Solar cycles are fundamental to astrophysics,space exploration,technological infrastructure,and Earth's climate.A better understanding of these cycles and their history can aid in risk mitigation on Earth,while also deepening our knowledge of stellar physics and solar system *** the solar cycles between 1600 and 1700-especially the post-1645 Maunder Minimum,characterized by significantly reduced solar activity-poses challenges to existing solar activity *** study utilizes a new red equatorial auroral catalog from ancient Korean texts to establish solar cycle patterns from 1623 to ***,a further reevaluation of the solar cycles between 1610 and 1755 identified a total of 13 cycles,diverging from the widely accepted record of 12 cycles during that *** research enhances our understanding of historical solar activity,and underscores the importance of integrating diverse historical sources into modern analyses.

关键词： solar cycle Maunder Minimum solar activity red equatorial aurora west Pacific geomagnetic anomaly

Discovery of a new family member of arsenic–vanadium polyoxometalates with high catalytic performance for one-pot coupling of CO2, epoxides and amines

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Tungsten 2025年第1期7卷 80-87页

作者： Fang-Qian wang Yin Zhang wei-wei wang Mei-Qian Fu Hong-Bing Mo wei-Dong Yu Chao Liu Jun Yan College of Chemistry and Chemical Engineering Central South University Junior Education Department Changsha Normal University School of Science Hunan University of Technology and Business

Arsenic-vanadium polyoxometalates（POMs） represent a family of tremendous potential catalysts owing to their peculiar physical and chemical *** in CO2conversion,using POMs to catalyze the conversion of CO2and epoxide into chemical intermediates is the research ***,A new family number of arsenic-vanadium POMs,[N（CH3）4]4[As8V12O38（H2O）]·2H2O({As8V12O38}),was reported and characterized by single-crystal X-ray diffraction,fourier transform infrared spectroscopy,X-ray photoelectron spectroscopy,*** from other allotropicity,{As8V12O38}shows a different structure pattern with an I-43d *** obtained {As8V12O38} was employed as a catalyst for the *** initial catalytic reaction confirmed that {As8V12O38} can catalyze the formation of epoxy carbonate by using 1.01 kPa CO2and epoxide at 70℃.Furtherly,when added amine in the catalytic system,oxazolidinone could be obtained by high yields,which provides an efficient way to convert CO2into profitable ***,a possible catalytic reaction mechanism was proposed by using different characterization analyses.{As8V12O38} first catalyzes the epoxide and CO2to form an epoxy carbonate and then catalyzes epoxy carbonate and benzylamine into oxazolidinone.

关键词： Arsenic CO2 conversion Oxazolidinone Polyoxometalates Vanadium

From text to image:challenges in integrating vision into ChatgPT for medical image interpretation

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Neural Regeneration Research 2025年第2期20卷 487-488页

作者： Shunsuke Koga wei Du Department of Pathology and Laboratory Medicine Hospital of the University of PennsylvaniaPhiladelphiaPAUSA

Large language models(LLMs),such as ChatgPT developed by OpenAI,represent a significant advancement in artificial intelligence(AI),designed to understand,generate,and interpret human language by analyzing extensive text *** potential integration into clinical settings offers a promising avenue that could transform clinical diagnosis and decision-making processes in the future(Thirunavukarasu et al.,2023).This article aims to provide an in-depth analysis of LLMs’current and potential impact on clinical *** ability to generate differential diagnosis lists underscores their potential as invaluable tools in medical practice and education(Hirosawa et al.,2023;Koga et al.,2023).

关键词： image diagnosis text

Record-breaking bifunctional oxygen electrocatalyst accomplished by a data-driven approach for zinc-air batteries

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Journal of Energy Chemistry 2025年第1期100卷 144-145页

作者： Deviprasath Chinnadurai Zhi wei Seh Institute of Materials Research and Engineering(IMRE) Agency for ScienceTechnologyand Research(A*STAR)2 Fusionopolis WayInnovis#08-03Singapore 138634Singapore

Rechargeable zinc-air batteries(ZABs) have recently drawn great attention in energy research due to their high theoretical capacity,low costs, and inherently safe nature [1–3]. However, the sluggish cathode reactions necessitate the development of bifunctional oxygen electrocatalysts with lower ΔE indicator values. The ΔE indicator is commonly employed to quantitatively evaluate the electrocatalytic activity of a bifunctional oxygen electrocatalyst,representing the overall overpotential from oxygen reduction reaction(ORR) to oxygen evolution reaction(OER).

关键词： breaking representing accomplished

water quality analysis and source apportionment in estuaries along the coast of the Bohai Sea,North China

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Journal of Oceanology and Limnology 2025年第1期43卷 73-89页

作者： guanghong wU Dan YE wei LUO Tianjin Key Laboratory of water Resources and Environment Tianjin Normal UniversityTianjin 300387China Laboratory of Solid waste Treatment and Recycling Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China

High-dimensional data(a dataset with many features)were collected from 64 sampling sites to analyze the water quality in estuaries along the coast of the Bohai Sea,North *** twenty-five water quality parameters analyzed were collected monthly from January 2021 to December *** statistical techniques,such as the absolute principal component score-multiple linear regression model(APCS-MLR),correlation analysis,and analysis of variance were used to identify and quantify the potential sources or factors affecting water quality and to analyze the spatial-temporal variation in water *** water quality indices(wQIs),ranging from 67.96 to 70.67,showed that the water quality was at an intermediate level in the estuaries during both the flood and nonflood *** concentrations of total phosphorus(TP),ammonia N(AN),and organic pollutants were greater in the Haihe River Basin than in the Liaohe River and Huanghe-Huaihe River *** concentration of total nitrogen(TN)in the Haihe River Basin was lower than that in the Liaohe River and Huanghe-Huaihe River *** metal concentrations in the Liaohe River Basin were greater than those in the Haihe River and Huanghe-Huaihe River *** annual mean concentrations of AN in the estuaries of the Haihe,Liaohe,and Huanghe(Yellow)rivers exhibited significant decreasing trends from 2013 to 2022,but no significant decreasing trends were found for permanganate index(COD_(Mn))or the *** concentrations of TN and AN were lower in the flood season than in the nonflood season,and the TP concentration was greater in the flood season than in the nonflood ***,the concentrations of organic pollutants did not exhibit significant *** sewage and industrial wastewater,substance exchange between air and water,nonpoint sources from rural and urban areas,and aquaculture wastewater were the major sources or factors responsible for water pollution in the estuaries.

关键词： water quality spatial-temporal variation source apportionment absolute principal component score-multiple linear regression estuary Bohai Sea

Dative B–N bonds weaven toward two-dimensional purely organic materials for single crystals

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Science China Chemistry 2025年第1期68卷 12-14页

作者： wei-Lei Zhou Siwei wang Yong Chen College of Chemistry and Materials Science Inner Mongolia Key Laboratory of Chemistry for Nature Products and Synthesis for Functional MoleculesInnovation Team of Optical Functional Molecular DevicesInner Mongolia Minzu UniversityTongliao 028000China College of Chemistry Nankai UniversityTianjin 300071China

Molecular topology is one of the important topics to study and understand the relationship between molecular structure and properties^([1]).Particularly,two-dimensional(2D)materials with extremely high surface area and ultra-thin morphology have attracted considerable attention due to their unexpected properties in materials and chemistry^([2,3]).

关键词： bonds purely dimensional

Applications of in-situ solid-state nuclear magnetic resonance in methanol to olefins reaction

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Science China Chemistry 2025年第1期68卷 134-151页

作者： Jing Niu Shutao Xu Yingxu wei Zhongmin Liu National Engineering Research Center of Lower-Carbon Catalysis Technology Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023China State Key Laboratory of Catalysis Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023China University of Chinese Academy of Sciences Beijing 100049China

The methanol-to-olefins(MTO)reaction offers an alternative pathway for the production of low-carbon olefins from non-oil *** research has been impeded by a lack of comprehensive understanding of its underlying mechanism,despite the significant progress made in ***-situ solid-state nuclear magnetic resonance(ss NMR)spectroscopy has emerged as a pivotal tool,offering crucial insights into key species under real-time operando ***,the host–guest interaction between zeolites or surface species residing on zeolites and the reactant/active intermediates is revealed by the combination of in-situ^(13)C MAS NMR and 2D correlation ***,recent technological advancements in hyperpolarization(HP)methods,including HP^(129)Xe NMR and dynamic nuclear polarization(DNP),have significantly improved the sensitivity of ssNMR,enabling detailed structural and kinetic analysis as well as the detection of trace *** this feature article,we summarized recent advancements in(in-situ)ssNMR spectroscopy applied to MTO reaction processes,encompassing mechanistic investigations at various stages and the intricate host–guest *** theoretical insights into the dynamic evolution of MTO reactions lay a solid foundation for the optimization of catalytic processes and the development of efficient catalysts,thereby advancing the techniques towards more sustainable and economical production route for olefins.

关键词： MTO zeolites in-situ ssNMR reactive intermediates reaction mechanism