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Failure of EB-PVD Thermal Barrier Coatings Subjected to Thermo-Mechanical Loading

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Chinese Journal of Aeronautics 2006年第B12期19卷 82-85页

作者： CHEN Chen zhang Chun-xia GUO Hong-bo GONG sheng-kai zhang Yue School of Materials Science and Engineering Beij＇ing University of Aeronautics and Astronautics Beijing 100083 China

Thermal barrier coatings （TBCs） were developed to protect metallic blades and vanes working in turbo-engines. The two-layered structure TBCs, consisting of NiCoCrAlY bond coat and yttria stabilized zirconia （YSZ）, were deposited on a cylinder of superalloy substrate by the electron beam-physical vapor deposition （EB-PVD）. The failure mechanism of the TBCs was investigated with a thermo-mechanical fatigue testing system under the service condition similar to that for turbine blades. Non-destructive evaluation of the coated specimens was conducted through the impedance spectroscopy. It is found that the crack initiation mainly takes place on the top coat at the edge of the heated zones.

关键词： electron beam-physical vapor deposition (EB-PVD) thermal barrier coatings (TBCs) thermal-mechanical loading impedance spectroscopy failure

Visible light promoted polyhalomethylation of alkenes: alkylation and cyclization

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Organic Chemistry Frontiers 2022年第4期9卷 1004-1009页

作者： Tong-Lin Wang bo-sheng zhang Jing-Jiang Liu Xiao-Jun Liu Xi-Cun Wang Zheng-Jun Quan Laboratory of Eco-Environment-Related Polymer Materials Ministry of EducationChina.College of Chemistry and Chemical EngineeringNorthwest Normal UniversityLanzhouGansu 730070People’s Republic of China

We report a visible light promoted carbochloromethylation of 2-bromomethyl acrylate and N-arylmethacrylamide,and a series of trihalomethyl substituted allylic acid esters and indolone derivatives were *** reaction used common and inexpensive chloroform and tribromomethane as tri-halomethyl reagents,iodobenzene diacetate(PIDA)as an oxidant and Eosin Y as a *** reaction conditions are mild and the substrate scope is wide.

关键词： promoted light cyclization

Reductive Coupling of Aryl Halides via C-H Activation of Indene

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Chinese Journal of Chemistry 2021年第6期39卷 1573-1579页

作者： bo-sheng zhang Ying-Hui Yang Fan Wang Xue-Ya Gou Xi-Cun Wang Yong-Min Liang Yuke Li Zheng-Jun Quan College of Chemistry and Chemical Engineering Gonsu International Scientific and Technological Cooperation Base of Water-Retention Chemical Functional MaterialsNorthwest Normal UniversityLanzhouGansu 730070China State Key Laboratory of Applied Organic Chemistry Lanzhou UniversityLanzhouGansu 730000China Department of Chemistry and Centre for Scientific Modeling and Computation Chinese University of Hong KongShatinHong KongChina

This paper describes the first case of a reductive coupling reaction with indene,a non-heteroatom olefin used as a reducing *** scope of the substrate is *** homo-coupling,cross-coupling,and synthesis of 12 and 14-membered rings were *** control experiment,indene-product curve and density functional theory calculations showed that the η^(3)-palladium indene intermediate was formed by C-H activation in the presence of cesium *** speculate that the final product was obtained through a Pd(IV)intermediate or aryl ligand *** addition,we excluded the formation of palladium anion(Pd(0)^(-))intermediates.

关键词： C-C coupling Palladium Reduction Indene C-H activation

Single-cell immune profiling reveals distinct immune response in asymptomatic COVID-19 patients

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Signal Transduction and Targeted Therapy 2021年第10期6卷 3108-3118页

作者： Xiang-Na Zhao Yue You Xiao-Ming Cui Hui-Xia Gao Guo-Lin Wang sheng-bo zhang Lin Yao Li-Jun Duan Ka-Li Zhu Yu-Ling Wang Li Li Jian-Hua Lu Hai-Bin Wang Jing-Fang Fan Huan-Wei Zheng Er-Hei Dai Lu-Yi Tian Mai-Juan Ma Center for Disease Control and Prevention of Chinese People's Liberation Army BeijingChina The Walter and Eliza Hall Institute of Medical Research ParkvilleVicAustralia Department of Medical Biology The University of MelbourneParkvilleVicAustralia State Key Laboratory of Pathogen and Biosecurity Beijing Institute of Microbiology and EpidemiologyBeijingChina The Fifth Hospital of Shijiazhuang Hebei Medical UniversityShijiazhuangChina

While some individuals infected by severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)present mild-to-severe disease,many SARS-CoV-2-infected individuals are *** sought to identify the distinction of immune response between asymptomatic and moderate *** performed single-cell transcriptome and T-cell/B-cell receptor(TCR/BCR)sequencing in 37 longitudinal collected peripheral blood mononuclear cell samples from asymptomatic,moderate,and severe patients with healthy *** patients displayed increased CD56^(bri)CD16^(-) natural killer(NK)cells and upregulation of interferon-gamma in effector CD4^(+) and CD8^(+) T cells and NK *** showed more robust TCR clonal expansion,especially in effector CD4^(+) T cells,but lack strong BCR clonal expansion compared to moderate ***,asymptomatic patients have lower interferon-stimulated genes(ISGs)expression in general but large interpatient variability,whereas moderate patients showed various magnitude and temporal dynamics of the ISGs expression across multiple cell populations but lower than a patient with severe *** data provide evidenee of different immune signatures to SARS-CoV-2 in asymptomatic infections.

关键词： patients asymptomatic interferon

Subretinal fibrosis secondary to neovascular age-related macular degeneration:mechanisms and potential therapeutic targets

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Neural Regeneration Research 2025年第2期20卷 378-393页

作者： Jingxiang zhang Xia sheng Quanju Ding Yujun Wang Jiwei Zhao Jingfa zhang Department of Ophthalmology People’s Hospital of Huangdao DistrictQingdaoShandong ProvinceChina Department of Urology People’s Hospital of Huangdao DistrictQingdaoShandong ProvinceChina Department of Ophthalmology Shanghai General Hospital(Shanghai First People’s Hospital)Shanghai Jiao Tong University School of MedicineShanghaiChina National Clinical Research Center for Eye Diseases Shanghai Key Laboratory of Ocular Fundus DiseasesShanghai Engineering Center for Visual Science and PhotomedicineShanghai Engineering Center for Precise Diagnosis and Treatment of Eye DiseasesShanghaiChina

Subretinal fibrosis is the end-stage sequelae of neovascular age-related macular *** causes local damage to photoreceptors,retinal pigment epithelium,and choroidal vessels,which leads to permanent central vision loss of patients with neovascular age-related macular *** pathogenesis of subretinal fibrosis is complex,and the underlying mechanisms are largely ***,there are no effective treatment options.A thorough understanding of the pathogenesis of subretinal fibrosis and its related mechanisms is important to elucidate its complications and explore potential *** current article reviews several aspects of subretinal fibrosis,including the current understanding on the relationship between neovascular age-related macular degeneration and subretinal fibrosis;multimodal imaging techniques for subretinal fibrosis;animal models for studying subretinal fibrosis;cellular and non-cellular constituents of subretinal fibrosis;pathophysiological mechanisms involved in subretinal fibrosis,such as aging,infiltration of macrophages,different sources of mesenchymal transition to myofibroblast,and activation of complement system and immune cells;and several key molecules and signaling pathways participating in the pathogenesis of subretinal fibrosis,such as vascular endothelial growth factor,connective tissue growth factor,fibroblast growth factor 2,platelet-derived growth factor and platelet-derived growth factor receptor-β,transforming growth factor-βsignaling pathway,Wnt signaling pathway,and the axis of heat shock protein 70-Toll-like receptors 2/*** review will improve the understanding of the pathogenesis of subretinal fibrosis,allow the discovery of molecular targets,and explore potential treatments for the management of subretinal fibrosis.

关键词： choroidal neovascularization epithelial-mesenchymal transition mesenchymal transition myofibroblast neovascular age-related macular degeneration submacular fibrosis subretinal fibrosis therapeutic targets transforming growth factor-β vascular endothelial growth factor

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基于族效应的波浪和砰击诱导应力的随机组合

上海交通大学学报 2003年第8期37卷 1155-1158,1163页

作者：黄文波张圣坤上海交通大学船舶与海洋工程学院上海200030

为了考查砰击的族效应对波浪和砰击诱导组合应力极值的影响 ,定义了泊松砰击族过程 .利用 Hansen的结果 ,确定平均族间距以及砰击族发生率 .当确定了相继两族砰击之间的组合极值后 ,可按传统的泊松砰击模型确定组合极值 .数值分析表明 ... 详细信息

为了考查砰击的族效应对波浪和砰击诱导组合应力极值的影响 ,定义了泊松砰击族过程 .利用 Hansen的结果 ,确定平均族间距以及砰击族发生率 .当确定了相继两族砰击之间的组合极值后 ,可按传统的泊松砰击模型确定组合极值 .数值分析表明 ,对于弱阻尼结构 ,考虑族效应会导致组合极值升高 ;对于强阻尼结构 ,考虑族效应会导致组合极值下降 .

关键词：波浪诱导应力砰击诱导应力族效应极值

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规范设计中一般平稳随机载荷过程的组合

上海交通大学学报 2001年第10期35卷 1433-1437页

作者：黄文波张圣坤上海交通大学船舶与海洋工程学院上海200030

给出了规范设计中确定载荷组合系数的一种新方法 .不同于 FBC模型及泊松模型 ,载荷用一般的平稳随机过程模拟 .利用 Grigoriu的非高斯载荷过程的平均上通率的一阶泊松近似 ,确定单个载荷及组合载荷的特征值 ,其中组合载荷过程的任一时... 详细信息

给出了规范设计中确定载荷组合系数的一种新方法 .不同于 FBC模型及泊松模型 ,载荷用一般的平稳随机过程模拟 .利用 Grigoriu的非高斯载荷过程的平均上通率的一阶泊松近似 ,确定单个载荷及组合载荷的特征值 ,其中组合载荷过程的任一时点分布用最大熵原理近似估计 .分析了不同载荷之间的相关性对组合系数的影响 ,对具有不同概率分布类型载荷的组合进行了数值分析 .最后该方法应用到波浪载荷与风载荷的组合 ,数值结果表明了方法的有效性 .

关键词：载荷组合随机过程平均上通率组合系数特征值规范设计结构设计

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非高斯平稳相关载荷过程的线性组合

上海交通大学学报 2001年第10期35卷 1450-1453页

作者：黄文波张圣坤上海交通大学船舶与海洋工程学院上海200030

采用 Winterstein的以矩为基础的上通率估计法 ,确定组合载荷的上通率及极值 .利用Terada的矩估计法 ,确定组合载荷的统计矩 .通过对具有不同概率密度函数的载荷过程的组合 ,分析了非高斯性和相关性对组合载荷特征值及载荷组合系数的影... 详细信息

采用 Winterstein的以矩为基础的上通率估计法 ,确定组合载荷的上通率及极值 .利用Terada的矩估计法 ,确定组合载荷的统计矩 .通过对具有不同概率密度函数的载荷过程的组合 ,分析了非高斯性和相关性对组合载荷特征值及载荷组合系数的影响 .结果表明 ,当用平稳随机过程模拟载荷过程时 ,忽略非高斯性及相关性会导致组合载荷特征值的低估 .

关键词：载荷组合随机过程平均上通率组合系数特征值结构设计

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船体时变可靠性分析

上海交通大学学报 2003年第8期37卷 1151-1154页

作者：黄文波张圣坤上海交通大学船舶与海洋工程学院上海200030

利用船体梁强度的单调退化特性 ,确定在设计寿命内船体强度的最小值 .由船体强度的最小值和载荷的最大值 ,根据经典的时不变可靠性理论 ,构造了一种新的时变可靠性表述形式 .同Guedes Soares和 Garbatov的基于随机过程上跨率的时变可靠... 详细信息

利用船体梁强度的单调退化特性 ,确定在设计寿命内船体强度的最小值 .由船体强度的最小值和载荷的最大值 ,根据经典的时不变可靠性理论 ,构造了一种新的时变可靠性表述形式 .同Guedes Soares和 Garbatov的基于随机过程上跨率的时变可靠性表述形式相比 ,这种新的时变可靠性表述形式 ,既能够展现疲劳和腐蚀所导致的船体可靠性随时间的连续变化 ,同时又避免了数值积分的麻烦 .因此这种方法计算量小 ,计算效率高 .

关键词：船体疲劳腐蚀时变可靠性