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Annals of Differential Equations 2009年第2期25卷 150-160页

作者： renji han,wei jiang (School of Math. and Computation Science,Anhui University,Hefei 230039) School of Math. and Computation Science Anhui University Hefei 230039

The problem of delay-dependent robust stability for uncertain linear singular neutral systems with time-varying and distributed delays is investigated. The uncertainties under consideration are norm bounded,and possibly time varying. Some new stability criteria,which are simpler and less conservative than existing results,are derived based on a new class of Lyapunov-Krasovskii functionals combined with the descriptor model transformation and the decomposition technique of coeffcient matrix and formulated in...

关键词： uncertain singular neutral differential systems time-varying delay distributed delay Lyapunov-functional LMI asymptotic stability

Parity-dependent skin effects and topological properties in the multilayer nonreciprocal Su−Schrieffer−Heeger structures

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Frontiers of physics 2024年第3期19卷 115-133页

作者： Jia-Rui Li Cui jiang han Su Di Qi Lian-Lian Zhang wei-jiang Gong College of Sciences Northeastern UniversityShenyang 110819China Basic Department Shenyang Institute of EngineeringShenyang 110136China

We concentrate on the skin effects and topological properties in the multilayer non-Hermitian Su−Schrieffer−Heeger (SSH) structure, by taking into account the nonreciprocal couplings between the different sublattices in the unit cells. Following the detailed demonstration of the theoretical method, we find that in this system, the skin effects and topological phase transitions induced by nonreciprocal couplings display the apparent parity effect, following the increase of the layer number of this SSH structure. On the one hand, the skin effect is determined by the parity of the layer number of this SSH system, as well as the parity of the band index of the bulk states. On the other hand, for the topological edge modes, such an interesting parity effect can also be observed clearly. Next, when the parameter disorders are taken into account, the zero-energy edge modes in the odd-layer structures tend to be more robust, whereas the other edge modes are easy to be destroyed. In view of these results, it can be ascertained that the findings in this work promote to understand the influences of nonreciprocal couplings on the skin effects and topological properties in the multilayer SSH lattices.

关键词： multilayer SSH lattice nonreciprocal couplings band structure skin effect

Seismic safety assessment with non-Gaussian random processes for train-bridge coupled systems

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Earthquake Engineering and Engineering Vibration 2024年第1期23卷 241-260页

作者： Zhao han Gao Lei wei Biao Tan Jincheng Guo Peidong jiang Lizhong Xiang Ping Key Laboratory of Geomechanics and Embankment Engineering of Ministry of Education Hohai UniversityNanjing 210024China School of Civil Engineering Central South UniversityChangsha 410075China

Extensive high-speed railway(HSR)network resembled the intricate vascular system of the human body,crisscrossing *** events,known for their unpredictability,pose a significant threat to both trains and bridges,given the HSR’s extended operational ***,ensuring the running safety of train-bridge coupled(TBC)system,primarily composed of simply supported beam bridges,is *** methods like the Monte Carlo method fall short in analyzing this intricate system ***,efficient algorithm like the new point estimate method combined with moment expansion approximation(NPEM-MEA)is applied to study random responses of numerical simulation TBC *** of the NPEM-MEA’s feasibility is conducted using the Monte Carlo *** analysis confirms the accuracy and efficiency of the method,with a recommended truncation order of four to six for the ***,the influences of seismic magnitude and epicentral distance are discussed based on the random dynamic responses in the TBC *** methodology not only facilitates seismic safety assessments for TBC systems but also contributes to standard-setting for these systems under earthquake conditions.

关键词： train-bridge coupled(TBC)system random vibration new point estimate method(NPEM) seismic safety assessment moment expansion approximation(MEA) non-Gaussian distributions

Electrocatalysts with atomic-level site for nitrate reduction to ammonia

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Journal of Energy Chemistry 2024年第9期96卷 642-668页

作者： Shuai Yin Rong Cao Yifan han Jiachangli Shang Jing Zhang wei jiang Guigao Liu National Special Superfine Powder Engineering Research Center School of Chemistry and Chemical EngineeringNanjing University of Science and TechnologyNanjing 210094JiangsuChina School of Pharmacy Jiangsu UniversityZhenjiang 212013JiangsuChina

Ammonia(NH_(3))is an important raw material for modern agriculture and industry,being widely demanded to sustain the sustainable development of modern ***,the industrial production methods of NH_(3),such as the traditional Haber-Bosch process,have drawbacks including high energy consumption and significant carbon dioxide *** recent years,the electrocatalytic nitrate reduction reaction(NO_(3)RR)powered by intermittent renewable energy sources has gradually become a multidisciplinary research hotspot,as it allows for the efficient synthesis of NH_(3)under mild *** this review,we focus on the research of electrocatalysts with atomic-level site,which have attracted attention due to their extremely high atomic utilization efficiency and unique structural characteristics in the field of NO_(3)***,we introduce the mechanism of nitrate reduction for ammonia synthesis and discuss the in-situ characterization techniques related to the mechanism ***,we review the progress of the electrocatalysts with atomic-level site for nitrate reduction and explore the structure-activity relationship to guide the rational design of efficient ***,the conclusions of this review and the challenges and prospective of this promising field are presented.

关键词： Ammonia synthesis Nitrate reduction Electrocatalysts with atomic-level site Reaction mechanism In-situ characterization techniques

High-Performance Anion Exchange Membrane Fuel Cells Enabled by Nitrogen Configuration Optimization in Graphene-Coated Nickel for Enhanced Hydrogen Oxidation

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Energy & Environmental Materials 2024年第5期7卷 345-352页

作者： Pan Li jiang Zhong Yanqing Fu Zhentao Du Lan jiang Yi han Jan Luxa Bing Wu Zdenek Sofer Qiliang wei weiyou Yang School of Resources Environment and Materials State Key Laboratory of Featured Metal Materials and Life-cycle Safety for Composite Structures Guangxi University Institute of Micro/Nano Materials and Devices Ningbo University of Technology Department of Inorganic Chemistry University of Chemistry and Technology Prague

Anion exchange membrane fuel cell （AEMFC） technology is attracting intensive attention,due to its great potential by using non-precious-metal catalysts （NPMCs） in the cathode and cheap bipolar plate materials in alkaline ***,in such case,the kinetics of hydrogen oxidation reaction （HOR） in the anode is two orders of magnitude sluggish than that of acidic electrolytes,which is recognized as the grand challenge in this ***,we report the rationally designed Ni nanoparticles encapsulated by N-doped graphene layers （Ni@NG） using a facile pyrolysis *** on the density functional theory calculations and electrochemical performance analysis,it is witnessed that the rich Pyridinic-N within the graphene shell optimizes the binding energy of the intermediates,thus enabling the fundamentally enhanced activity for HOR with robust *** a proof of concept,the resultant Ni@NG sample as the anode with a low loading(1.8 mg cm-2) in AEMFCs delivers a high peak power density of500 mW cm-2,outperforming all of those of NPMC-based analogs ever reported.

关键词： anion-exchange-membrane fuel cells density functional calculations hydrogen oxidation reaction Ni-based non-precious-metal catalysts pyridinic N-doped graphene

Evolution exploration and structure prediction of Keggin-type group IVB metal-oxo clusters

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Chinese Chemical Letters 2024年第5期35卷 487-492页

作者： Run-han Li Tian-Yi Dang wei Guan jiang Liu Ya-Qian Lan Zhong-Min Su School of Chemistry South China Normal UniversityGuangzhou 510006China Institute of Functional Material Chemistry Faculty of ChemistryNortheast Normal UniversityChangchun 130024China Institute of Theoretical Chemistry Jilin UniversityChangchun 130023China

The fascinating chemical structure and broad application prospect of Keggin-type polyoxometalates(POMs)have attracted many chemists to explore and discover *** the traditional Keggin,larger metal atomic radius,higher metal coordinated numbers,lower metal valence states and other features allow the group IVB metal-based Keggin(IVB-Keggin)more space and unknown in terms of structure and ***,density functional theory(DFT)calculations were performed to explore the influences including cores,shells,caps,and terminal ligands,et *** IVB-Keggin,and analyze the possibility of novel structure *** the perspective of multi-layer onion-like clusters,molecular energy level,host-guest interaction energy,surface charge and covalent bond polarity can be further adjusted to achieve the oriented design of functional *** insights are expected to provide theoretical support for experimental synthesis,opening a new perspective to understand the growth of Keggin.

关键词： Keggin Metal-oxo clusters Group IVB Onion pattern DFT

Synthesis-temperature-dependent phase composition manipulation toward high thermoelectric performance in tetrahedrites

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Journal of Materials Science & Technology 2024年第1期168卷 124-130页

作者： Yiqing wei Jiaqi Liu Zien Cheng Pengfei jiang Zizhen Zhou Bin Zhang Guoyu Wang Guang han Xu Lu Xiaoyuan Zhou Center of Quantum Materials and Devices College of PhysicsChongqing UniversityChongqing 401331China College of Materials Science and Engineering Chongqing UniversityChongqing 400044China College of Chemistry and Chemical Engineering Chongqing UniversityChongqing 401331China Analytical and Testing Center Chongqing UniversityChongqing 401331China

Tetrahedrite,an Earth-abundant natural mineral,has attracted extensive research interest because of its excellent thermoelectric ***,tetrahedrite samples comprising Cu-poor Cu_(12)Sb_(4)S_(13)and Cu-rich Cu_(14)Sb_(4)S_(13)phases have been synthesized using a colloidal method,in which the ratio of two phases is manipulated by controlling the synthesis temperature to improve the thermoelectric *** is found that an ultralow total thermal conductivity of∼0.3 W m^(−1)K^(−1)at 723 K is realized in the sample with a Cu-rich phase fraction of∼50%,which can be attributed to maximized phonon scattering by phase *** a result,combined with a decent power factor,this sample obtains an optimal zT of 1.15,which is about 85%higher than that of the sample with a Cu-rich phase fraction of∼64%and comparable to zT values of other eco-friendly,abundant Cu-based thermoelectric *** work demonstrates an effective synthesis-temperature-dependent phase composition manipulation strategy toward enhanced thermoelectric performance in tetrahedrites.

关键词： Tetrahedrite Thermoelectric Colloidal method Phase manipulation Thermal conductivity

Bioceramic scaffolds with two-step internal/external modification of copper-containing polydopamine enhance antibacterial and alveolar bone regeneration capability

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2024年第1期25卷 65-82页

作者： Xiaojian jiang Lihong LEI weilian SUN Yingming wei Jiayin han Shuaiqi ZHONG Xianyan YANG Zhongru GOU Lili CHEN Department of Oral Medicine the Second Affiliated HospitalZhejiang University School of MedicineHangzhou310009China Bio-nanomaterials and Regenerative Medicine Research Division Zhejiang–California International Nanosystem InstituteZhejiang UniversityHangzhou310058China

Magnesium-doped calcium silicate(CS)bioceramic scaffolds have unique advantages in mandibular defect repair;however,they lack antibacterial properties to cope with the complex oral ***,for the first time,the CS scaffold was functionally modified with a novel copper-containing polydopamine(PDA(Cu^(2+)))rapid deposition method,to construct internally modified(*P),externally modified(@PDA),and dually modified(*P@PDA)*** morphology,degradation behavior,and mechanical properties of the obtained scaffolds were evaluated in *** results showed that the CS*P@PDA had a unique micro-/nano-structural surface and appreciable mechanical *** the prolonged immersion stage,the release of copper ions from the CS*P@PDA scaffolds was rapid in the early stage and exhibited long-term sustained *** in vitro evaluation revealed that the release behavior of copper ions ascribed an excellent antibacterial effect to the CS*P@PDA,while the scaffolds retained good cytocompatibility with improved osteogenesis and angiogenesis ***,the PDA(Cu^(2+))-modified scaffolds showed effective early bone regeneration in a critical-size rabbit mandibular defect ***,it was indicated that considerable antibacterial property along with the enhancement of alveolar bone regeneration can be imparted to the scaffold by the two-step PDA(Cu^(2+))modification,and the convenience and wide applicability of this technique make it a promising strategy to avoid bacterial infections on implants.

关键词： Copper-containing polydopamine Modification Antibacterial property Bone regeneration Angiogenesis Bioceramic scaffold

Red-emissive carbon quantum dots minimize phototoxicity for rapid and long-term lipid droplet monitoring

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Chinese Chemical Letters 2024年第10期35卷 341-347页

作者： Fengkai Zou Borui Su han Leng Nini Xin Shichao jiang Dan wei Mei Yang Youhua Wang Hongsong Fan Department of Orthopedics Affiliated Hospital of Nantong UniversityNantong 226001China Graduate School Dalian Medical UniversityDalian 116044China National Engineering Research Center for Biomaterials College of Biomedical EngineeringSichuan UniversityChengdu 610064China School of Chemistry and Chemical Engineering Liaoning Normal UniversityDalian 116029China

Long-term fluorescence monitoring of subcellular organelles is crucial for cellular physiology and pathology *** droplets(LDs)are increasingly recognized for their involvement in various biological processes,to influence disease development through diverse behaviors However,existing LD probes face challenges in achieving high targeting and long-term monitoring due to poor photostability and long-term *** quantum dots(CQDs)have gained prominence due to their exceptional fluorescence properties,but their prevalent blue excitation wavelength presents difficulties for long-term ***,we synthesized red-emissive carbon quantum dot(R-CQDs)with superior photobleaching resistance and red-emission,thus enabling harmlessly fluorescence monitoring of cells longer than3 *** addition,R-CQD exhibits suitable amphiphilicity and remarkable solvatochromic effect,allowing rapid targeting to LDs for immediate imaging without cumbersome washing ***,R-CQD shows high performance for extended observation of dynamic LD behavior in various biological processes,which is confirmed by documenting the course of LDs during starvation as well as *** to commercial probes,R-CQD extends live cell imaging time by at least 9-fold,facilitating the study of LD behavioral characteristics under diverse physiological or pathological *** work provides a reliable fluorescence tool for tracking intercellular microenvironment dynamically thus to understand the divers biological or disease mechanism.

关键词： Carbon quantum dots Solvatochromism Lipid droplet probe Fluorescence imaging Wash-free

On-chip integrated GeSe_(2)/Si vdW heterojunction for ultravioletenhanced broadband photodetection,imaging,and secure optical communication

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Nano Research 2024年第7期17卷 6544-6549页

作者： Zhiman Zhou Kunxuan Liu Di Wu Yunrui jiang Ranran Zhuo Pei Lin Zhifeng Shi Yongtao Tian wei han Longhui Zeng Xinjian Li School of Physics and Microelectronics Key Laboratory of Material Physics Ministry of EducationZhengzhou UniversityZhengzhou 450052China Department of Electrical and Computer Engineering University of California San DiegoLa JollaCalifornia 92093USA Institute of Microelectronics and Integrated Circuits School of MicroelectronicsHubei UniversityWuhan 430062China

Broadband photodetection,spanning from ultraviolet(UV)to infrared(IR),is pivotal in diverse technological domains including astronomy,remote sensing,environmental monitoring,and medical ***,current commercially available broadband photodetectors,predominately based on conventional narrow-bandgap semiconductors,exhibit limited sensitivity in the UV *** limitation,stemming from the significant energy disparity between the semiconductor bandgap and UV photon,narrows their application ***,we report an innovative approach involving the in-situ van der Waals(vdW)integration of two-dimensional(2D)GeSe_(2)layers onto a Si *** process yields a high-quality GeSe_(2)/Si vdW heterojunction device,which features a broad response range covering from UV to near-IR(NIR)with a greatly-enhanced sensitivity in the UV *** device possesses high responsivities of 325 and 533.4 mA/W,large detectivities of 1.24×10^(13)and 2.57×10^(13)Jones,and fast response speeds of 20.6/82.1 and 17.7/81.0μs under 360 and 980 nm,***,the broadband image sensing and secure invisible optical communication capabilities of the GeSe_(2)/Si heterojunction device are *** work provides a viable approach for UV-enhanced broadband photodetection technology,opening up new possibilities and applications across various scientific and technological domains.

关键词： germanium diselenide van der Waals(vdW)integration ultraviolet enhanced broadband photodetection imaging