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Preparation of CePO_4-coated zirconia ceramics and their mechanical behavior

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Rare Metals 2011年第3期30卷 282-286页

作者： ZI Wei SU Cunping LIN Yuanhua WANG yong deng Xuliang Department of VIP Dental Service Peking University School and Hospital of Stomatology Beijing 100081 China Department of Materials Science and Engineering Tsinghua University Beijing 100084 China Jiamusi University School and Hospital of Stomatology Heilongjiang Jiamusi 154002 China

Tetragonal ZrO2-3 mol% Y2O3 （3Y-TZP） coated with CePO4 was synthesized by a co-precipitation method and the effects of CePO4 content and sintering temperature on its mechanical properties were investigated. The microstructure and phase composition of the products were characterized using scanning and transmission electron microscopy as well as X-ray diffraction, respectively. The machinability index of CePO4-coated zirconia was calculated to be 1.05 when the CePO4 content is 25 wt.%. The sample hardness, bending strength and fracture toughness are 7.08 GPa, 457.85 MPa and 9.75 MPa m1/2, respectively, when the sintering temperature is 1400°C. The results show that as-prepared CePO4-coated 3Y-TZP ceramics are highly suitable biomaterials for dental applications and are expected to be used in a com-puter-aided design and computer-aided manufacturing （CAD/CAM） system to make dental crowns or bridge prostheses in a one-step sinter-ing process.

关键词： ceramic materials zirconia machinability X-ray analysis biomedical engineering

Effects of environmental factors on corrosion behaviors of metal-fiber porous components in a simulated direct methanol fuel cell environment

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International Journal of Minerals,Metallurgy and Materials 2014年第9期21卷 913-918页

作者： Wei Yuan Bo Zhou yong Tang Zhao-chun Zhang Jun deng Key Laboratory of Surface Functional Structure Manufacturing of Guangdong Higher Education Institutes School of Mechanical and Automotive Engineering South China University of Technology

Abstract： To enable the use of metallic components in direct methanol fuel cells （DMFCs）, issues related to corrosion resistance must be considered because of an acid environment induced by the solid electrolyte. In this study, we report the electrochemical behaviors of metal-fiber-based porous sintered components in a simulated corrosive environment of DMFCs. Three materials were evaluated： pure copper, AISI304, and AISI316L. The environmental factors and related mechanisms affecting the corrosion behaviors were analyzed. The results demonstrated that AISI316L exhibits the best performance. A higher SO4^2- concentration increases the risk of material corrosion, whereas an increase in methanol concentration inhibits corrosion. The morphological features of the corroded samples were also characterized in this study.

关键词： corrosion metal fibers porous sintering direct methanol fuel cells environmental factors

A fuzzy grey cognitive maps-based decision support system for maintaining water quality

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A fuzzy grey cognitive maps-based decision support system fo...

Flow resistance in the channel-bar landscape of large alluvial rivers

第25届中国控制与决策会议

作者： Bingyi Kang yong deng Jiangsu Key Laboratory of Resources and Environmental Information Engineering China University of Mining and Technology School of Computer and Information Science Southwest University

ISBN: (纸本)9781467355339

Maintaining water quality is of great importance for consumer’s health. How to evaluate and predict the aging water quality is an open issue. In this paper, a framework based on fuzzy grey cognitive maps （FGCMs） is proposed to quantify overall potential for water quality failures. A new method of aggregating different experts based on interval number is presented in the process of constructing FGCM. At last, a case study is utilized to illustrate the efficiency of the proposed method.

关键词： Water Quality Management Fuzzy Grey Cognitive Maps Interval number

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Frontiers of Earth Science 2024年第2期18卷 412-421页

作者： yong HU Congcong LIU Jinyun deng Wei ZHANG Yitian LI State Key Laboratory of Water Resources and Hydropower Engineering Science Wuhan UniversityWuhan 430072China CCCC Second Harbor Engineering Company Ltd Wuhan 430040China Key Laboratory of Large-span Bridge Construction Technology Wuhan 430040China Research and Development Center of Transport Industry of Intelligent Manufacturing Technologies of Transport Infrastructure Wuhan 430040China CCCC Highway Bridge National Engineering Research Centre Co.Ltd Wuhan 430040China

Accurate approaches for estimating flow resistance in large alluvial rivers are fundamental for simulating discharge,sediment transport,and flood ***,methods for estimating riverbed resistance and additional resistance in the channel-bar landscapes remain poorly *** this study,we used in situ river bathymetry,sediment,and hydraulic data from the Shashi Reach in the Yangtze River to develop a semi-empirical approach for calculating flow *** method quantitatively separates flow resistance into riverbed resistance and additional resistance and shows high accuracy in terms of deviation ratio(~20%),root-mean-square error(~0.008),and geometric standard deviation(~3).Additional resistance plays a dominant role under low-flow conditions but a secondary role under high flows,primarily due to the reduction in momentum exchange in channel-bar regions as discharge *** resistance first decreases and then increases,which might be attributed to bedform changes in the lower and transitional flow regimes as flow velocity ***,our findings further the understanding of dynamic changes in flow resistance in the channel-bar landscapes of large river systems and have important implications for riverine ecology and flood management.

关键词： flow resistance channel-bar landscape interaction region large river bedform

Disturbance observer based finite-time coordinated attitude tracking control for spacecraft on SO(3)

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Journal of Systems Engineering and Electronics 2020年第6期31卷 1274-1285页

作者： SHI Zhen XIE Yaen deng Chengchen ZHAO Kun HE Yushan HAO yong College of Automation Harbin Engineering UniversityHarbin 150001China College of Aerospace and Civil Engineering Harbin Engineering UniversityHarbin 150001China

To solve the problem of attitude synchronization control for spacecraft formation flying(SFF)suffering from external disturbances under a directed communication topology,a sliding mode disturbance observer(SMDO)based on the finite-time control strategy is developed to observe the time-varying external disturbance via estimating the upper bound of its first ***,the rotation matrix is employed to describe the attitude of SFF for the purpose of the avoidance of singularity and unwinding *** for the attitude synchronization and the tracking control architecture,a sliding mode surface(SMS)is given such that the control objective can be *** effectiveness and the validity of the proposed method are elaborated via theoretical analysis and numerical simulations.

关键词： coordinated attitude control disturbance observer rotation matrix attitude synchronization control

Diffusion of nanochannel-confined knot along a tensioned polymer

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Communications in Theoretical Physics 2024年第4期76卷 158-166页

作者： Guobing Cai yong Li Yuyu Feng Zhouhui deng Yanhui Liu College of Physics Guizhou UniversityGuiyang 550025China Kechuang Industrial Development Company Limited Guian New AreaGuiyang 550025China State Key Laboratory of Public Big Data Guizhou UniversityGuiyang 550025China

The knots frequently occur in biopolymer and their diffusion plays an active role in the gene *** this work,Langevin dynamics simulations were carried out to detect the diffusion behaviours of a knot along a tensioned polymer in different spatial *** polymer accommodating a knot was tethered to two macrospheres to block the unravelling of the *** a result,the curves for the diffusion coefficients of the knot with different bending stiffness as a function of the tension in different spatial constraints were *** the space without constraints or with weak constraints,the corresponding curves for the knot with relatively large bending stiffness exhibited two turnover *** the contrary,for the knot with relatively small bending stiffness,the diffusion coefficients were monotonically reduced with increasing ***,in a space with strong constraints,all the curves showed one turnover behaviour regardless of the bending *** turnover behaviours divided the curves into different regimes,and the dominant diffusion mechanisms in the regimes,namely,knot-region breathing,self-reptation,and internal friction,were clearly *** effective friction coefficientsξof the knots with 3_(1),4_(1),5_(1) and 5_(2) types as a function of the knot size N at a fixed tension were well fitted by the relationξ∝*** effective friction coefficients of the knots at relatively large tension f>3 sharply increased with the knot complexity,which is not dependent on the spatial *** contrast,the values of these coefficients at relatively small tension f≤3 were remarkably dependent on the spatial *** work not only provides valuable simulation results to assist the understanding of the diffusion of DNA knot,but also highlights the single-molecule design for the manipulation of DNA knots in future.

关键词： knot langevin dynamics simulations diffusion coefficient self-reptation knot-region breathing internal friction

Combustion behavior and mechanism of molecular perovskite energetic material DAP-4-based composites with metal fuel Al

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Defence Technology（防务技术） 2023年第9期27卷 53-63页

作者： Peng deng Xue-yong Guo Hua Fang Rui Liu Peng-wan Chen State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing100081PR China

Combined with the oxidizer anions and fuel cations,molecular perovskite energetic materials show a good *** this work,the combustion behavior and mechanism of metal fuel aluminium(Al)with molecular perovskite energetic material(H_(2)dabco)[NH4(ClO_(4))_(3)](DAP-4)as a high-energy oxidant was *** DAP-4 based composites with metal fuel Al were designed and fabricated by the different mass *** showed that DAP-4 exhibits a good oxygen-supplied capacity for enhancing the combustion performance of *** maximum combustion heat of DAP-4/Al-3 at the Al/O mass ratio of 38:62 is up to 10,412 J/g in the inert gas,which is higher than those of other ratios and the mixtures of other energetic materials and *** evolution of pressure output,pressurization rate,and flame temperature was monitored for DAP-4/Al with different mass *** DAP-4/Al/F were characterized by burning *** combustion reaction mechanism of metal fuel Al with DAP-4 as a high-energy oxidant was ***-4 was ignited firstly and released acid and oxidizing gases,which corroded Al_(2)O_(3)shells on Al particle surfaces and accelerated the combustion reaction with Al to release a lot of *** work offered a new idea that molecular perovskite energetic materials have great potential in the high-energy Al-based solid rocket propellants.

关键词： DAP-4 Metal fuel al Oxidant Combustion behavior Reaction mechanism

Ionic Liquid/Poly(ionic liquid)-based Semi-solid State Electrolytes for Lithium-ion Batteries

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Chinese Journal of Polymer Science 2020年第5期38卷 506-513,I0006页

作者： deng-Zhou Zhang yong-Yuan Ren Yin Hu Liang Li Feng Yan Hubei Key Laboratory of Plasma Chemistry and Advanced Materials College of Materials Science and EngineeringWuhan Institute of TechnologyWuhan 430205China Jiangsu Key Laboratory of Advanced Functional Polymer Design and Application College of ChemistryChemical Engineering and Materials ScienceSoochow UniversitySuzhou 215123China

Ionic liquids(ILs)have appeared as the most promising electrolytes for lithium-ion batteries,owing to their unique high ionic conductivity,chemical stability and thermal stability ***(ionic liquid)s(PILs)with both IL-like characteristic and polymer structure are emerging as an alternative of traditional *** this review,recent progresses on the applications of IL/PIL-based semi-solid state electrolytes,including gel electrolytes,ionic plastic crystal electrolytes,hybrid electrolytes and single-ion conducting electrolytes for lithium-ion batteries are discussed.

关键词： Ionic liquids Poly(ionic liquid)s Semi-solid state electrolytes Lithium-ion batteries

Asymmetric Zn-N_4 atomic sites embedded hollow fibers as stable Zn anode for high-performance Zn-ion hybrid capacitor

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Journal of Energy Chemistry 2024年第10期97卷 460-469,I0009页

作者： Yukun Liu Bing Li Jin Wang Caiyun Li Hongrui Yang Yang Song sen Zhang Chao deng Key Laboratory for Photonic and Electronic Bandgap Materials Ministry of EducationCollege of Physics and Electronic EngineeringHarbin Normal UniversityHarbin 150025HeilongjiangChina College of Material Science and Chemical Engineering Harbin Engineering UniversityHarbin 150001HeilongjiangChina

Zn based electrochemical energy storage systems(EES)have attracted tremendous interests owing to their low cost and high intrinsic ***,the uncontrolled growth of Zn dendrites and the side reactions of Zn metal anodes(ZMAs)severely restrict their *** address these issues,we design the asymmetric Zn-N_(4) atomic sites embedded hollow fibers(AS-IHF)as the flexible host for stable *** introducing different nitrogen resources in the synthesis,two kinds of coordination,i,***-N(pyridinic)and Zn-N(pyrrolic),are introduced in the Zn-N_(4) atomic module *** asymmetric Zn-N_(4) module with regulated micro-environment facilitates the superior zincophilic features and promotes the Zn ***,the highly porous structure of the hollow fiber effectively reduces local current density,homogenize Zn ion flux,and alleviate structure *** the advantages endow the high efficiency and good stability for Zn plating/*** theoretical and experimental results demonstrate the high reversibility,low nucleation overpotential,and dendritefree behavior of the AS-IHF@Zn anode,which afford the high stability in high-rate and long-term ***,the solid-state Zn-ion hybrid capacitor(ZIHC)based on AS-IHF@Zn anode shows the high flexibility,reliability,and superior long-term cycling capability in a wide-range of temperatures(-20-25℃).Therefore,the present work not only gives a new strategy for modulating local environments of single atomic sites,but also propels the development of flexible power sources for diverse electronics.

关键词： Asymmetric coordination Single atomic sites Zincophilic sites Dendrite free behavior Zn-ion hybrid capacitor