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Journal of Pharmaceutical Analysis 2009年第3期21卷 149-154页

作者： Jing Li1,2.Zhi-ying Ma11. School of Electrical engineering,Xi’an Jiaotong University,Xi’an 710049 2. School of Electrical Information,Hunan institute of engineering,Xiangtan 411101,China. School of Electrical engineering Xi'an Jiaotong University Xi'an 710049 China School of Electrical Information Hunan Institute of Engineering Xiangtan 411101 China

By using a self-developed IF power and a ASTM contact material experimental system of small-capacity and variable frequency,the value of arcing characteristics and the welding force of the silver-based contact material are acquired under low voltage,resistive load and small current at 400 Hz and 50 Hz. By means of an electricity-ray analytical balance,SEM and EDAX,the weighing values of the contact materials and the changes of AgCdO,AgNi,AgC and AgW contact material surface profile and micro-area constituent are obtained and analyzed. The arc erosion causes of silver-based alloy contact materials at 400 Hz and 50 Hz are also discussed.

关键词： silver-based alloy low voltage 400 Hz 50 Hz contact material arc erosion

A Review of Ion Beam Assisted Deposition of Thermal Barrier Coatings

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稀有金属材料与工程 2011年第S4期40卷 215-217页

作者： Liu Liang1,2.Gao Wei2.Zhang Huafang2.Lei Xingen2.Cui Xiangzhong2.Zheng Yufeng1 1Centre for Biomedical Materials and engineering,Harbin engineering University,Harbin 150001,China2.cience and Technology on Power Beam Processes Laboratory,AVIC Beijing Aeronautical Manufacturing Technology {2. institute,Beijing 10002.,China Harbin Engn Univ Ctr Biomed Mat & Engn Harbin 150001 Peoples R China AVIC Beijing Aeronaut Mfg Technol Res Inst Sci & Technol Power Beam Proc Lab Beijing 100024 Peoples R China

Ion beam assisted deposition (IBAD) technology has been employed more and more in the fabrication of films and/or coatings,especially in the composite *** the present work,after the introduction about IBAD,the latest development of IBAD in thermal barrier coatings (TBCs) is briefly summarized and the future trend is also concluded.

关键词： ion beam assisted deposition ion source thermal barrier coatings thermal conductivity

Assessment on Chloride Contaminated Resistance of Concrete with Non-steady-state Migration Method

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Journal of Wuhan University of Technology(Materials Science) 2004年第4期19卷 6-8页

作者：候浩波 Wuhan University

A preparation technology of chloride contaminated resistant concrete was presented. The newly developed non-steady-state migration test method was employed for the evaluation of chloride ions diffusion coefficient of the concrete. The experimental results show that this method has a good correlation with the traditional NT Build 443 method, and it provides an effective and quick approach to assess the resistant capacity of concrete against chloride ions.

关键词： high performance concrete durability chloride contaminated diffusion coefficient

Synthesis and Luminescence Properties of Pr^(3+) Doped Ca_xBa_(1-x)TiO_3 (0.3≤x<1) Fine Particles

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Journal of Wuhan University of Technology(Materials Science) 2009年第5期24卷 689-693页

作者：何声太 College of Materials Science and engineering Tianjin Polytechnic University

CaxBa1-xTiO3 （CBT） fine particles doped with red luminescence center of Pr3＋ ions （Pr： CBT） were successfully synthesized by salt assisted spray pyrolysis （SASP） process. Scanning electronic microscope （SEM） and laser scattering analysis demonstrate that salt can be removed from the surface of particles by washing with Milli-Q water and the particles can be further separated by ball-milling to get well-dispersed Pr^3＋ ions doped CBT fine particles. The luminescence properties, such as photoluminescence （PL） and mechanoluminescence （ML）, of as-synthesized Pr： CBT particles were investigated. For Pr： CBT fine particles with different Ca molar ratios, all the samples show one emission at 612.nm, with increasing Ca molar ratio, PL intensity of Pr： CBT fine particles become stronger and stronger. When pressure was loaded on the Pr： CBT pellet, mechanoluminescence（ML） emission was measured. The results show that the ML intensity is proportional to the applied pressure.

关键词： synthesis luminescence mechanoluminescence photoluminescence Pr^3+ doped CaxBa1-xTiO3 fine particles

Nanostructured Sulfide Composite Coating Prepared by Atmospheric Plasma Spraying

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材料工程 2006年第Z1期34卷 281-284页

作者： GUAN Yao-hui~1,XU Yang~1,ZHENG Zhong-yu~2.TONG Xiao-hui~2.1 engineering College of China Agricultural University,Beijing 100083,China 2.Beijing research {2. of Mechanical & Electrical Technology,Beijing 100083,China) engineering College China Agricultural University Beijing 100083 China Beijing research institute of Mechanical and Electrical Technology Beijing 100083 China

Nanostructured FeS-SiC coating was deposited by atmospheric plasma spraying（APS）.The microstructure and phase composition of the coating were characterized with SEM and XRD,*** addition,the size distribution of the reconstituted powders and the porosity of the coating have been *** was found that the reconstitiuted powers with sizes in the range of 2. to 80 μm had excellent flowability and were suitable for plasma spraying *** as-sprayed FeS-SiC composite coating exhibited a bimodal distribution with small grains（30～80nm） and large grains（100～2.0nm）.The coating was mainly composed of FeS and SiC,a small quantity of Fe1-xS and oxide were also *** porosity of the coating was approximately 19%.

关键词： plasma spraying nanostructured FeS-SiC composite coating

Gas kinetic algorithm for flows in Poiseuille-like microchannels using Boltzmann model equation

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Science China(Physics,Mechanics & Astronomy) 2005年第4期48卷 496-512页

作者： LI Zhihui1,2. ZHANG Hanxin1 & FU Song2.⒈ National Laboratory for CFD, Hypervelocity Aerodynamics institute,China Aerodynamics research and Development Center,Mianyang 62.000,China 2.Department of {2. Mechanics,Tsinghua University,Beijing 100084,China 1. National Laboratory for CFD Hypervelocity Aerodynamics Institute China Aerodynamics Research and Development Center 621000 Mianyang China 2. Department of engineering Mechanics Tsinghua University 100084 Beijing China

The gas-kinetic unified algorithm using Boltzmann model equation have been extended and developed to solve the micro-scale gas flows in Poiseuille-like micro-channels from Micro-Electro-Mechanical Systems (MEMS). The numerical modeling of the gas kinetic boundary conditions suitable for micro-scale gas flows is presented. To test the present method, the classical Couette flows with various Knudsen numbers, the gas flows from short microchannels like plane Poiseuille and the pressure-driven gas flows in two-dimensional short microchannels have been simulated and compared with the approximate solutions of the Boltzmann equation, the related DSMC results, the modified N-S solutions with slip-flow boundary theory, the gas-kinetic BGK-Burnett solutions and the experimental data. The comparisons show that the present gas-kinetic numerical algorithm using the mesoscopic Boltzmann simplified velocity distribution function equation can effectively simulate and reveal the gas flows in microchannels. The numerical experience indicates that this method may be a powerful tool in the numerical simulation of micro-scale gas flows from MEMS.

关键词： Boltzmann model equation, discrete velocity ordinate method, finite-difference scheme, Couette flow, Poiseuille flow, gas flow in short-microchannel.

Pyridine-H_5PMo_(10)V_2._(40) hybrid catalysts for liquid-phase hydroxylation of benzene to phenol with molecular oxygen

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Science China Chemistry 2009年第8期52卷 1264-1269页

作者： GE HanQing1,LENG Yan1,ZHANG FuMin1,PIAO JiaRui2.ZHOU ChangJiang1 & WANG Jun1 1 State Key Laboratory of Materials-Oriented Chemical engineering,College of Chemistry and Chemical engineering,Nanjing University of Technology,Nanjing 2.0009,China 2.Petrochemical {2. institute,PetroChina Company ltd.,Beijing 100083,China 1. State Key Laboratory of Materials-Oriented Chemical engineering College of Chemistry and Chemical Engineering Nanjing University of Technology Nanjing 210009 China 2. Petrochemical research institute PetroChina Company Ltd. Beijing 100083 China

Pyridine(Py)-modified Keggin-type vanadium-substituted heteropoly acids(PynPMo10V2.40,n=1 to 5) were prepared by a precipitation method as organic/inorganic hybrid catalysts for direct hydroxylation of benzene to phenol in a pressured batch reactor and their structures were detected by *** various catalysts,Py3PMo10V2.40 exhibits the highest catalytic activity(yield of phenol,11.5%),without observing the formation of catechol,hydroquinone and benzoquinone in the reaction with 80 vol% aqueous acetic acid,molecular oxygen and ascorbic acid used as the solvent,oxidant and reducing reagent,*** of reaction temperature,reaction time,oxygen pressure,amount of ascorbic acid and catalyst on yield of phenol were investigated to obtain the optimal reaction conditions for phenol *** can greatly promote the catalytic activity of the Py-free catalyst(H5PMo10V2.40),mostly because the organic π electrons in the hybrid catalyst may extend their conjugation to the inorganic framework of heteropoly acid and dramatically modify the redox properties,at the same time,pyridine adsorbed on heteropoly acids can promote the effect of "pseudo-liquid phase",thus accounting for the enhancement of phenol yield.

关键词： hydroxylation benzene organic/inorganic hybrid catalyst phenol heteropoly acid pyridine

Comparison of Photochemical Reactions of m-Cresol in Aqueous Solution and in Ice

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Chemical research in Chinese Universities 2012年第1期28卷 47-52页

作者： PENG Fei1, XUE Hong-hai1, TANG Xiao-jian1,2. KANG Chun-li1, LI Lin-lin1 and LI Zhe1 1. Key Laboratory of Groundwater Resources and Environment, Ministry of Education, Jilin University, Changchun 13002., P. R. China 2. School of Municipal and Environmental engineering, Jilin institute of Architecture and Civil engineering, Changchun 130118, P. R. China Jilin Univ Key Lab Groundwater Resources & Environm Minist Educ Changchun 130021 Peoples R China Jilin Inst Architecture & Civil Engn Sch Municipal & Environm Engn Changchun 130118 Peoples R China

We compared the photochemical reaction of m-cresol containing ·OH precursors such as H2.2. NO2.and NO3 in aqueous solution with those in ice. The results show that the conversion rate of m-cresol in aqueous solution was higher than that in ice. H2.2. NO2.and NO3 all accelerated the photoconversion of m-cresol in both aqueous solution and ice. The photochemical reactions of m-cresol obeys the first order kinetics equation. According to the photoproducts identified by GC-MS, we proposed that hydroxylation and nitration reactions occurred in both aqueous solution and ice. Coupling reaction was common in ice, however, in aqueous solution it was found only in UV system. Our results suggest that the photochemical reactions of m-cresol were different in aqueous solution and in ice.

关键词： m-Cresol Photochemistry Aqueous solution Ice Mechanism

UAV-Assisted Dynamic Avatar Task Migration for Vehicular Metaverse Services: A Multi-Agent Deep Reinforcement Learning Approach

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IEEE/CAA Journal of Automatica Sinica 2024年第2期11卷 430-445页

作者： Jiawen Kang Junlong Chen Minrui Xu Zehui Xiong Yutao Jiao Luchao Han Dusit Niyato Yongju Tong shengli Xie IEEE School of Automation Guangdong University of TechnologyGuangzhou 510006China 111 Center for Intelligent Batch Manufacturing based on IoT Technology Guangzhou 510006China Key Laboratory of Intelligent Information Processing and System Integration of IoT Ministry of EducationGuangzhou 510006China School of Computer Science and engineering Nanyang Technological UniversitySingaporeSingapore Pillar of Information Systems Technology and Design Singapore University of Technology and DesignSingaporeSingapore College of Communication engineering Army Engineering University of PLANanjing 210007China National Natural Science Foundation of China Beijing 100085China Key Laboratory of Intelligent Detection and IoT in Manufacturing Ministry of EducationGuangzhou 510006China Guangdong Key Laboratory of IoT Information Technology Guangzhou 510006China

Avatars, as promising digital representations and service assistants of users in Metaverses, can enable drivers and passengers to immerse themselves in 3D virtual services and spaces of UAV-assisted vehicular Metaverses. However, avatar tasks include a multitude of human-to-avatar and avatar-to-avatar interactive applications, e.g., augmented reality navigation,which consumes intensive computing resources. It is inefficient and impractical for vehicles to process avatar tasks locally. Fortunately, migrating avatar tasks to the nearest roadside units(RSU)or unmanned aerial vehicles(UAV) for execution is a promising solution to decrease computation overhead and reduce task processing latency, while the high mobility of vehicles brings challenges for vehicles to independently perform avatar migration decisions depending on current and future vehicle status. To address these challenges, in this paper, we propose a novel avatar task migration system based on multi-agent deep reinforcement learning(MADRL) to execute immersive vehicular avatar tasks dynamically. Specifically, we first formulate the problem of avatar task migration from vehicles to RSUs/UAVs as a partially observable Markov decision process that can be solved by MADRL algorithms. We then design the multi-agent proximal policy optimization(MAPPO) approach as the MADRL algorithm for the avatar task migration problem. To overcome slow convergence resulting from the curse of dimensionality and non-stationary issues caused by shared parameters in MAPPO, we further propose a transformer-based MAPPO approach via sequential decision-making models for the efficient representation of relationships among agents. Finally, to motivate terrestrial or non-terrestrial edge servers(e.g., RSUs or UAVs) to share computation resources and ensure traceability of the sharing records, we apply smart contracts and blockchain technologies to achieve secure sharing management. Numerical results demonstrate that the proposed approach

关键词： Avatar blockchain metaverses multi-agent deep reinforcement learning transformer UAVs

Core-Shell Semiconductor-Graphene Nanoarchitectures for Efficient Photocatalysis:State of the Art and Perspectives

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Nano-Micro Letters 2024年第12期16卷 553-588页

作者： Jinshen Lan Shanzhi Qu Xiaofang Ye Yifan Zheng Mengwei Ma Shengshi Guo shengli Huang Shuping Li Junyong Kang engineering research Center of Micro-Nano Optoelectronic Materials and Devices Ministry of EducationFujian Key Laboratory of Semiconductor Materials and ApplicationsCI Center for OSEDDepartment of PhysicsXiamen UniversityXiamen 361005People’s Republic of China

Semiconductor photocatalysis holds great promise for renewable energy generation and environment remediation,but generally suffers from the serious drawbacks on light absorption,charge generation and transport,and structural stability that limit the *** core-shell semiconductorgraphene(CSSG)nanoarchitectures may address these issues due to their unique structures with exceptional physical and chemical *** review explores recent advances of the CSSG nanoarchitectures in the photocatalytic *** starts with the classification of the CSSG nanoarchitectures by the ***,the construction methods under internal and external driving forces were introduced and compared with each ***,the physicochemical properties and photocatalytic applications of these nanoarchitectures were discussed,with a focus on their role in *** ends with a summary and some perspectives on future development of the CSSG nanoarchitectures toward highly efficient photocatalysts with extensive *** harnessing the synergistic capabilities of the CSSG architectures,we aim to address pressing environmental and energy challenges and drive scientific progress in these fields.

关键词： Core-shell semiconductor-graphene Nanoarchitecture Photocatalysis Driving force Interface