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Mechanism of forming an ink-bottle-like pore structure based on SBA-15 by a novel MOCVD technique

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Chinese Science Bulletin 2010年第4期55卷 446-451页

作者： ZHANG Ying frank leung-yuk lam YAN ZiFeng HU XiJun School of Chemistry & Chemical Engineering China University of Petroleum Dongying 257061 China Department of Chemical Engineering Hong Kong University of Science and Technology Clear Water Bay Kowloon Hong Kong China

Metallorganic chemical vapor deposition is used as a novel simple pore tailoring method to fine-tune the pore opening size of SBA-15 materials without significant loss in pore volume and surface area. By using acetylene as carbon source and copper (II) acetylacetonate as precursor, the poremouth of SBA-15 is effectively reduced from 5.78 nm to 3.67 nm while maintaining the pore body at 5.78 nm. The effect of four pore modification factors-the ratio of acetylene/nitrogen, the feeding time of carbon precursor, the ratio of SBA-C/Cu(acac)2 and the cycles of MOCVD on the final pore structure of the SBA-15/carbon/copper composite is studied. The morphology and microstructure of the resulting product SBA-C-Cu are characterized by XRD patterns, TEM images and EDS analysis. The XRD and TEM reveal that the SBA-C-Cu composite is highly hexagonally ordered and has similar particle morphology as the original SBA-15.

关键词：金属有机化学气相沉积化学气相沉积技术 SBA 分子筛孔结构铜复合材料化学气相沉积法透射电子显微镜

Mechanism of forming an ink-bottle-like pore structure based on SBA-15 by a novel MOCVD technique

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Science Bulletin 2010年第Z1期 446-451页

作者： frank leung-yuk lam Department of Chemical Engineering Hong Kong University of Science and Technology Clear Water Bay Kowloon Hong Kong China

关键词： ink-bottle-like pore MOCVD SBA-15

Fabrication of copper (Ⅰ) nitride nanorods within SBA-15 by metal organic chemical vapor deposition

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Science China(Technological Sciences) 2009年第2期52卷 352-356页

作者： ZHANG Ying1,2, frank leung-yuk lam2, YAN ZiFeng1 & HU XiJun2 1 School of Chemistry & Chemical Engineering, China University of Petroleum, Dongying 257061, China 2 Department of Chemical Engineering, Hong Kong University of Science and Technology, Hong Kong, China School of Chemistry & Chemical Engineering China University of Petroleum Dongying China Department of Chemical Engineering Hong Kong University of Science and Technology Hong Kong China

Copper (Ⅰ) nitride nanorods grown in channels of mesoporous silica SBA-15 by chemical vapor deposition method has been synthesized. The morphology and microstructure of the resulting product were characterized by XRD patters, TEM images, EDS analysis and Raman spectra. The XRD and TEM revealed that the Cu3N phase was confined in channels of SBA-15 forming continuous nanowires with 6 nm around and hundreds of nanometers in length. Raman spectra of the final product and pure Cu3N showed peaks shift due to the quantum confinement effect of the nanowires. This preparation methodology only requires a mild working condition and is capable of template synthesis of other binary nitride nanostructures with controlled morphology inside the channels of mesoporous materials.

关键词： nanorods copper nitride CVD SBA-15

Load-sharing mechanism in timber-steel hybrid shear wall systems

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Frontiers of Structural and Civil Engineering 2015年第2期9卷 203-214页

作者： Zheng LI Minjuan HE frank lam Minghao LI Department of Structural Engineering Tongji University Shanghai 200092 China Department of Wood Science University of British Columbia Vancouver V6T 1Z4 Canada Department of Civil & Natural Resources Engineering University of Canterbury Christchurch New Zealand

The lateral performance of timber-steel hybrid shear wall systems with regard to the interaction between the steel frame and the infill wood shear wall was investigated in this paper. A numerical model for the timber-steel hybrid shear wall system was developed and verified against test results. Design parameters, such as the lateral infill-to-frame stiffness ratio and the arrangements of wood-steel bolted connections were studied using the numerical model. Some design recommendations were also proposed based on the parametric analysis. In the hybrid shear wall system, the infill wood wall was found to resist a major part of the lateral load within relatively small wall drifts, and then the steel frame provided more lateral resistance. Under seismic loads, the infill wood wall could significantly reduce the inter-story drift of the hybrid system, and a complementary effect between the infill wood wall and the steel frame was observed through different lateral load resisting mechanisms, which provided robustness to the hybrid shear wall systems.

关键词： timer-steel hybrid shear wall load sharing mechanism seismic performance parametric analysis

Catalytically active interfaces in titania nanorod-supported copper catalysts for CO oxidation

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Nano Research 2020年第2期13卷 533-542页

作者： Wasim U.Khan Season S.Chen Daniel C.W.Tsang Wey Yang Teoh Xijun Hu frank L.Y.lam Alex C.K.Yip Department of Chemical and Process Engineering The University of Canterbury Christchurch 8041New Zealand Department of Civil and Environmental Engineering.The Hong Kong Polytechnic University Hong Kong.China School of Chemical Engineering The University of New South WalesSydneyNSW 2052Australia Department of Chemical and Biological Engineering The Hong Kong University of Science and TechnologyHong KongChina

One-dimensional titanium dioxide nanorod(TNR)-supported Cu catalysts(2.5 wt.%-12.5 wt.%)were synthesized using deposition-precipitation.X-ray photoelectron spectroscopy,temperature programmed reduction and CO chemisorption measurements showed that Cu doping over TNR offered metal-support interactions and interfacial active sites that had a profound impact on the catalytic *** role of the Cu-TNR interface was investigated by comparing the catalytic activity of Cu-TNR catalysts with that of pure CuO nanoparticles in CO *** presence of highly dispersed copper species,a high number of interfacial active sites,CO adsorption capacity and surface/lattice oxygen were found to be responsible for the excellent activity of 7.5CU-TNR(ie,Cu loading of 7.5 wt.%on TNR).Moreover,the Cu-TNR catalysts followed the Langmuir-Hinshelwood reaction mechanism with 7.5CU-TNR,exhibiting an apparent activation energy of 44.7 kJ/*** TNR-supported Cu catalyst gave the highest interfacial catalytic activity in medium-temperature CO oxidation(120-240℃)compared to other commonly used supports,including titanium dioxide nanoparticles(TiO2-P25),silica(SiO2)and alumina(Al20g)in which copper species were nonhomogeneously *** study confirms that medium-temperature CO oxidation is highly sensitive to the morphology and structure of the supporting material.

关键词： supported catalysts nanorod oxygen species interfacial active sites CO oxidation

Sampled-data control through model-free reinforcement learning with effective experience replay

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Journal of Automation and Intelligence 2023年第1期2卷 20-30页

作者： Bo Xiao H.K.lam Xiaojie Su Ziwei Wang frank P.-W.Lo Shihong Chen Eric Yeatman Department of Electrical and Electronic Engineering Imperial College LondonLondon SW72AZUK Department of Engineering King’s College LondonLondon WC2B 4BGUK Department of Automation Chongqing UniversityShapingba DistrictChong QingChina School of Engineering Lancaster UniversityLA14YWUK Hamlyn Centre Imperial College LondonLondon SW72AZUK

Reinforcement Learning(RL)based control algorithms can learn the control strategies for nonlinear and uncertain environment during interacting with *** by the rewards generated by environment,a RL agent can learn the control strategy directly in a model-free way instead of investigating the dynamic model of the *** the paper,we propose the sampled-data RL control strategy to reduce the computational *** the sampled-data control strategy,the whole control system is of a hybrid structure,in which the plant is of continuous structure while the controller(RL agent)adopts a discrete *** that the continuous states of the plant will be the input of the agent,the state–action value function is approximated by the fully connected feed-forward neural networks(FCFFNN).Instead of learning the controller at every step during the interaction with the environment,the learning and acting stages are decoupled to learn the control strategy more effectively through experience *** the acting stage,the most effective experience obtained during the interaction with the environment will be stored and during the learning stage,the stored experience will be replayed to customized times,which helps enhance the experience replay *** effectiveness of proposed approach will be verified by simulation examples.

关键词： Reinforcement learning Neural networks Sampled-data control Model-free Effective experience replay

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肢体无力的男性患者一例

英国医学杂志中文版 2021年第1期24卷 59-60页

作者： Shing Fung Lee Pui lam Yip frank Chi Sing Wong 毛晨晖(译) Department of Clinical Oncology Tuen Mun HospitalNew Territory West Cluster Hospital AuthorityHong Kong 中国医学科学院北京协和医院神经科

58岁男性,以进行性右侧肢体无力和头痛一周就诊。他每周饮酒约7个单位,20年前戒烟(既往吸烟10包/年)。近期无头外伤史,未服用药物或毒品。神志清楚,无发热、体重下降或盗汗等症状。体格检查一般情况好,无发热,无脑膜炎体征或视乳头水肿... 详细信息

58岁男性,以进行性右侧肢体无力和头痛一周就诊。他每周饮酒约7个单位,20年前戒烟(既往吸烟10包/年)。近期无头外伤史,未服用药物或毒品。神志清楚,无发热、体重下降或盗汗等症状。体格检查一般情况好,无发热,无脑膜炎体征或视乳头水肿,右侧上下肢肌力4级,左侧肌力5级1。血常规、肝功能、电解质、C反应蛋白正常。颅脑钆增强磁共振成像(MRI)如图所示(图1)。

关键词：下肢肌力视乳头水肿 C反应蛋白体格检查脑膜炎体重下降外伤史血常规