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Applied Mathematics and Mechanics(English Edition) 2024年第7期45卷 1225-1242页

作者： zhou HU Zhibo WEI Yan CHEN Rui ZHU School of Aerospace Engineering Beijing Institute of Technology School of Mechanical Engineering Tianjin University Key Laboratory of Mechanism Theory and Equipment Design of Ministry of Education Tianjin University

Elastic metamaterials with unusual elastic properties offer unprecedented ways to modulate the polarization and propagation of elastic waves. However, most of them rely on the resonant structural components, and thus are frequency-dependent and unchangeable. Here, we present a reconfigurable 2D mechanism-based metamaterial which possesses transformable and frequency-independent elastic properties. Based on the proposed mechanism-based metamaterial, interesting functionalities, such as ternarycoded elastic wave polarizer and programmable refraction, are demonstrated. Particularly, unique ternary-coded polarizers, with 1-trit polarization filtering and 2-trit polarization separating of longitudinal and transverse waves, are first achieved. Then, the strong anisotropy of the proposed metamaterial is harnessed to realize positive-negative bi-refraction, only-positive refraction, and only-negative refraction. Finally, the wave functions with detailed microstructures are numerically verified.

关键词： elastic metamaterial elastic wave reconfigurable design zero mode ternary code programmable refraction O343 74j05

A novel approach to determine residual stress field during FSW of AZ91 Mg alloy using combined smoothed particle hydrodynamics/neuro-fuzzy computations and ultrasonic testing

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journal of Magnesium and Alloys 2021年第4期9卷 1311-1335页

作者： A.R.Eivani H.Vafaeenezhad H.R.jafarian j.zhou School of metallurgy and materials engineering iran university of science and technology^nartnaktehraniran department of biomechanical engineering delft university of technologymekehveg 22628 cd delftthe netherlands

The faults in welding design and process every so often yield defective parts during friction stir welding(FSW).The development of numerical approaches including the finite element method(FEM)provides a way to draw a process paradigm before any physical *** is not practical to simulate all possible designs to identify the optimal FSW practice due to the inefficiency associated with concurrent modeling of material flow and heat dissipation throughout the *** study intends to develop a computational workflow based on the mesh-free FEM framework named smoothed particle hydrodynamics(SPH)which was integrated with adaptive neuro-fiizzy inference system(ANFIS)to evaluate the residual stress in the FSW *** integrated SPH and ANFIS methodology was established and the well-trained ANIS was then used to predict how the FSW process depends on its *** verify the SPH calculation,an itemized FSW case was performed on AZ91 Mg alloy and the induced residual stress was measured by ultrasonic *** suggested methodology can efficiently predict the residual stress distribution throughout friction stir welding of AZ91 alloy.

关键词： Friction stir welding(FSW) Smoothed particle hydrodynamics(SPH) Adaptive neuro-fuzzy inference system(ANFIS) Ultrasonic Residual stress

A Note of the Interpolating Sequence in Qp∩H~∞

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Wuhan University journal of Natural Sciences 2024年第1期29卷 1-6页

作者： zhou jizhen SUN Hejie School of Mathematics and Big Data Anhui University of Science and Technology

In this paper,{zn}n=1~∞ acts as an interpolating sequence for Qp∩H~∞.An analytic function f is constructed,and f(zn)=∑jλjfzj(zn)=λn,n=1,2,…for any {λn}∈l~∞,wheref and ■ belong to Qp∩H~∞.As a result,the st... 详细信息

关键词： Q_p space H∞ space F (p,p - 2,s) ∩H~∞ interpolating sequence

Full-spectrum Bi@SrTiO_(3) for bi-directional promotion effects on photocatalytic redox reaction:Insight into intermediates and mechanism

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journal of Rare Earths 2024年第5期42卷 917-929,I0004页

作者： Bin Liu Nanhao zhou jun Liu Xinglei Wang Peter K.j.Robertson Xiaoyuan Chen Chao Chen jianmin Luo Chuanyi Wang School of Chemistry and Civil Engineering Shaoguan UniversityShaoguan512005China Chengdu Customs Technology Center Chengdu610041China Key Laboratory of Pollutant Chemistry and Environmental Treatment College of Chemistry and Environmental ScienceYili Normal UniversityYining835000China School of Chemistry and Chemical Engineering Queen's University BelfastStranmillis RoadBelfastBT95AGUnited Kingdom Guangzhou Institute of Industrial Intelligence(GIII) Guangzhou511400China

The development of full-spectrum photocatalysts active in the near-infrared(NIR)region has gained increasing attention for deleterious pollutant *** integration of plasmonic metals with semico nductors is an effective way to widen the light re sponse range of photocatalysts due to the strong light absorption and fast plasmonic energy transfer of the localized surface plasmon resonance(LSPR).In this work,the full-spectrum responsive Bi@SrTiO_(3) was prepared via facile solvothermal chemical *** optimal Bi@SrTiO_(3) achieves exceptional photocatalytic Cr(VI)reduction efficiency and tetracycline degradation,realizing bi-directional promotion effects on redox *** to density functional theory(DFT)simulations,the extraordinary photocatalytic performance is attributed to the tunable builtin electric field(IEF)of the Ohmic *** favorable adaptability in real water and high stability of BSTO-25 were proved by experime ntal *** the po ssible photocatalytic mechanism was proposed based on theoretical calculation and experimental ***,the non-toxicity of the BSTO-25 was evaluated by *** cultivation,which further proves the feasibility of treating wastewater with *** work provides a new perspective on constructing full-spectrum-driven photocatalysts for applications dealing with environmental remediation.

关键词： Full-spectrum photocatalysts Localized surface plasmon resonance Ohmic contact Cr(Ⅵ)reduction Antibiotic degradation Rare earths

The effect of bacterial challenge on ferritin regulation in the yellow fever mosquito, Aedes aegypti

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Insect Science 2013年第5期20卷 601-619页

作者： Dawn L. Geiser Guoli zhou jonathan j. Mayo joy j. Winzerling Department of Nutritional Sciences College of Agriculture and Life Sciences the University of Arizona Tucson Arizona 85721 USA

Secreted ferritin is the major iron storage and transport protein in insects. Here, we characterize the message and protein expression profiles of yellow fever mosquito （Aedes aegypti） ferritin heavy chain homologue （HCH） and light chain homologue （LCH） subunits in response to iron and bacterial challenge. In vivo experiments demonstrated tissue-specific regulation of HCH and LCH expression over time post-blood meal （PBM）. Transcriptional regulation of HCH and LCH was treatment specific, with differences in regulation for na？ve versus mosquitoes challenged with heat-killed bacteria （HKB）. Translational regulation by iron regulatory protein （IRP） binding activity for the iron-responsive element （IRE） was tissue-specific and time-dependent PBM. However, mosquitoes challenged with HKB showed little change in IRP/IRE binding activity compared to na？ve animals. The changes in ferritin regulation and expression in vivo were confirmed with in vitro studies. We challenged mosquitoes with HKB followed by a blood meal to determine the effects on ferritin expression, and demonstrate a synergistic, time-dependent regulation of expression for HCH and LCH.

关键词： Aedes aegypti bacteria ferritin iron IRP mosquito

Effect of Mo on microstructural characteristics and coarsening kinetics of γ' precipitates in Co–Al–W–Ta–Ti alloys

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journal of Materials Science & Technology 2018年第5期34卷 799-805页

作者： H.j.zhou F.Xue H.Chang Q.Feng State Key Laboratory for Advanced Metals and Materials University of Science and Technology Beijing National Center for Materials Service Safety University of Science and Technology Beijing

The solvus temperature,volume fraction,coarsening behavior of γ＇ precipitates and the partitioning behavior of alloying elements as well as lattice misfit of γ/γ＇ phases influence the creep behavior of Ni-and Co-base ***,few investigations about the microstructural characteristics and the coarsening behavior of γ＇ precipitates were reported in multicomponent novel Co-base superalloys during thermal *** alloys containing different contents of molybdenum and tungsten have been investigated to explore the effect of molybdenum on γ＇ solvus temperature,γ ＋γ＇ microstructure and γ＇ coarsening in Co–Al–W–Ta–Ti-base *** results showed that the γ＇ solvus temperature decreases with the addition of *** addition reduces the Y＇ volume fractions after aging above 1000℃,but results in negligible influence on the γ＇ volume fractions aging at 900℃.Meanwhile,γ＇ coarsening is controlled by diffusion in experimental alloys after aging at 900℃ and 1000℃,and the kinetics of Y＇growth in experimental alloys are consistent with the predictions of LSW theory.

关键词： Cobalt alloys Molybdenum Coarsening Microstructure

Study on Fluorescence Property of Sparfloxacin Derivatizing System and its Application

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Chinese Chemical Letters 2000年第3期11卷 255-258页

作者： Du, LM zhou, j Xu, QQ Fan, ZF Yuan, R Shanxi Normal Univ Ctr Anal & Test Linfen 041004 Peoples R China

In acid medium, sparfloxacin is oxidized by nitrous acid, then reacts with hydrobromic acid to form a new fluorescence substance, which can emit the strong fluorescence. which is 151 fold more than that of sparfloxacin itself. By this, a new sensitive method for the determination of sparfloxacin in human urine by derivative-synchronous fluorescence is presented with good results.

关键词： sparfloxacin nitrous acid derivative-synchronous fluorescence human urine

A NEW CYCLOPEPTIDE FROM VACCARIA SEGETALIS

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Chinese Chemical Letters 1995年第8期6卷 681-682页

作者： Zhang, RP Zou, C Chai, YK zhou, j Acad Sinica Kunming Inst Bot Lab Phytochem Kunming 650204 Peoples R China

A new cyclopeptide designated as vaccarin A were isolated from the seeds of Vaccaria segetalis, Its structure was obtained by spectral evidence.

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Ga(X)N/Si nanoarchitecture:An emerging semiconductor platform for sunlight-powered water splitting toward hydrogen

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Frontiers in Energy 2024年第1期18卷 56-79页

作者： Yixin LI Sharif Md.SADAF Baowen zhou Key Laboratory for Power Machinery and Engineering of the Ministry of Education Research Center for Renewable Synthetic FuelSchool of Mechanical EngineeringShanghai Jiao Tong UniversityShanghai 200240China Centre Energie Matériaux et TélécommunicationsInstitut National de la Recherche Scientifique(INRS)-Universitédu Québec1650 Boulevard Lionel-BouletVarennesQuébec J3X1S2Canada

Sunlight-powered water splitting presents a promising strategy for converting intermittent and virtually unlimited solar energy into energy-dense and storable green *** the pioneering discovery by Honda and Fujishima,considerable efforts have been made in this research *** various materials developed,Ga(X)N/Si(X=In,Ge,Mg,etc.)nanoarchitecture has emerged as a disruptive semiconductor platform to split water toward hydrogen by *** paper introduces the characteristics,properties,and growth/synthesis/fabrication methods of Ga(X)N/Si nanoarchitecture,primarily focusing on explaining the suitability as an ideal platform for sunlight-powered water splitting toward green hydrogen *** addition,it exclusively summarizes the recent progress and development of Ga(X)N/Si nanoarchitecture for photocatalytic and photoelectrochemical water ***,it describes the challenges and prospects of artificial photosynthesis integrated device and system using Ga(X)N/Si nanoarchitectures for solar water splitting toward hydrogen.

关键词： Ga(X)N/Si nanoarchitecture artificial photosynthesis water splitting solar toward hydrogen

Fault Estimation for a Class of Markov jump Piecewise-Affine Systems: Current Feedback Based Iterative Learning Approach

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IEEE/CAA journal of Automatica Sinica 2024年第2期11卷 418-429页

作者： Yanzheng Zhu Nuo Xu Fen Wu Xinkai Chen Donghua zhou IEEE College of Electrical Engineering and Automation Shandong University of Science and TechnologyQingdao 266590China College of Mechanical Engineering and Automation Huaqiao UniversityXiamen 361021China Department of Mechanical and Aerospace Engineering North Carolina State UniversityRaleigh NC 27695 USA Department of Electronic and Information Systems Shibaura Institute of TechnologySaitama 337-8570Japan

In this paper, the issues of stochastic stability analysis and fault estimation are investigated for a class of continuoustime Markov jump piecewise-affine(PWA) systems against actuator and sensor faults. Firstly, a novel mode-dependent PWA iterative learning observer with current feedback is designed to estimate the system states and faults, simultaneously, which contains both the previous iteration information and the current feedback mechanism. The auxiliary feedback channel optimizes the response speed of the observer, therefore the estimation error would converge to zero rapidly. Then, sufficient conditions for stochastic stability with guaranteed performance are demonstrated for the estimation error system, and the equivalence relations between the system information and the estimated information can be established via iterative accumulating ***, two illustrative examples containing a class of tunnel diode circuit systems are presented to fully demonstrate the effectiveness and superiority of the proposed iterative learning observer with current feedback.

关键词： Current feedback fault estimation iterative learning observer Markov jump piecewise-affine system