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Acta Metallurgica Sinica(English Letters) 1993年第8期6卷 130-136页

作者： wu Chuansong,cao Zhenning,wu Lin Harbin Institute of Technology,Harbin,China

A model is established to analyze three-dimensional fluid flow and heat transfer in TICweld pools with full *** considers the deformation of the molten pool surfaceat the condition of full penetrated workpieees,takes the are pressure as the drivingforce of the pool surface deformation,and determines the surface configuration of weldpool based on the dynamic balance of arc pressure,pool gravity and surface tension atdeformed weld pool surface. The SIMPLER algorithm is used to calculate the fluid flowfield and temperature distribution in TIG weld pools of stainless steel *** experiments are made to verify the validity of the *** shows the calculatedresults by the model are in good agreement with experimental measurements. professor,Dept of Welding Engineering,Harbin Institute of Technology,Harbin 150006,China

关键词： TIG weld pool full penetration fluid flow heat transfer numerical analysis

Enhanced AC Fault Ride-through Control for MMC-integrated System Based on Active PCC Voltage Drop

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现代电力系统与清洁能源学报(英文) 2023年第4期11卷 1316-1330页

作者： Haihan Ye wu Chen Heng wu wu cao Guoqing He Guanghui Li Center for Advanced Power Conversion Technology and Equipment School of Electrical EngineeringSoutheast UniversityNanjing 210096China Department of Energy Technology Aalborg University9220 AalborgDenmark China Electric Power Research Institute Beijing 100192China

When a renewable energy station(RES)connects to the rectifier station(RS)of a modular multilevel converterbased high-voltage direct current(MMC-HVDC)system,the voltage at the point of common coupling(PCC)is determined by RS control *** example,RS control may become saturated under fault,and causes the RS to change from an equivalent voltage source to an equivalent current source,making fault analysis more *** addition,the grid code of the fault ride-through(FRT)requires the RES to output current according to its terminal *** changes the fault point voltage and leads to RES voltage regulation and current redistribution,resulting in fault response *** address these issues,this study describes how an MMC-integrated system has five operation modes and three common characteristics under the duration of the *** study also reveals several instances of RS performance degradation such as AC voltage loop saturation,and shows that RS power reversal can be significantly *** enhanced AC FRT control method is proposed to achieve controllable PCC voltage and continuous power transmission by actively reducing the PCC voltage *** robustness of the method is theoretically proven under parameter variation and operation mode ***,the feasibility of the proposed method is verified through MATLAB/Simulink results.

关键词： Modular multilevel converter-based high-voltage direct current(MMC-HVDC)system fault ride-through(FRT) voltage loop saturation continuous power transmission point of common coupling(PCC) active voltage drop control

碳/铝复合材料界面Al_(4)C_(3)相的形成与调控研究进展

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中国有色金属学报 2024年第5期34卷 1453-1474页

作者：李肖亮李昱桦董正学万梓涵任可聪邓海亮杨康吴操安徽工业大学先进金属材料绿色制备与表面技术教育部重点实验室马鞍山243002 安徽工业大学材料科学与工程学院先进陶瓷研究中心马鞍山243002 四川航天天盛装备科技有限公司成都610100

石墨烯、碳纳米管和碳纤维等碳材料作为铝基复合材料的增强体时,其界面润湿性差、与Al基体结合弱等缺点限制了其增强效果。利用C与Al反应使界面黏接形式转变为部分反应结合的形式,可有效提升碳/铝(C/Al)界面强度及其载荷与功能传递的效... 详细信息

石墨烯、碳纳米管和碳纤维等碳材料作为铝基复合材料的增强体时,其界面润湿性差、与Al基体结合弱等缺点限制了其增强效果。利用C与Al反应使界面黏接形式转变为部分反应结合的形式,可有效提升碳/铝(C/Al)界面强度及其载荷与功能传递的效率。然而,高温下C/Al界面反应易生成大量脆性Al_(4)C_(3),且会损伤增强体。针对C/Al界面Al_(4)C_(3)的调控,本文首先介绍了其形成机制、对C/Al复合材料界面结合和性能的作用,随后从碳增强体表面涂层、纳米颗粒修饰、Al基体合金化,以及复合制备、热加工与处理工艺优化等方面,综述了Al_(4)C_(3)生成量与形貌的控制研究及效果,最后展望了C/Al复合材料界面与性能的研究方向,以期通过碳增强体跨尺度设计与界面构型控制,挖掘石墨烯、碳纳米管和碳纤维增强Al基体的最大潜能。

关键词：铝基复合材料石墨烯碳纳米管碳纤维 Al_(4)C_(3)相

帕金森病合并运动过弱型构音障碍诊治的研究进展

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中国临床神经外科杂志 2024年第4期29卷 236-238,242页

作者：王宇航曹胜武南京医科大学第一附属医院神经外科南京210000

大多数帕金森病(PD)病人会有不同程度的构音障碍,称为运动过弱型构音障碍(HD)。HD不仅对PD病人语言清晰度、有效沟通、参与社会活动等产生不利的影响,甚至会诱发或加重PD病人的抑郁、自闭等心理疾病,从而引起生活质量的严重下降。本文... 详细信息

大多数帕金森病(PD)病人会有不同程度的构音障碍,称为运动过弱型构音障碍(HD)。HD不仅对PD病人语言清晰度、有效沟通、参与社会活动等产生不利的影响,甚至会诱发或加重PD病人的抑郁、自闭等心理疾病,从而引起生活质量的严重下降。本文就PD病人合并HD的病理生理学机制、言语特征、早期诊断意义、治疗等研究进展进行综述,为临床提供参考。

关键词：帕金森病运动过弱型构音障碍多巴胺肌肉僵硬早期诊断

Resilience-incorporated seismic risk assessment of precast concrete frames with“dry”connections

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Earthquake Engineering and Engineering Vibration 2024年第2期23卷 403-425页

作者： wu Chenhao Tang Yuchuan cao Xuyang wu Gang Key Laboratory of Concrete and Prestressed Concrete Structures of the Ministry of Education Nanjing 211102China Department of Civil and Environmental Engineering University of CaliforniaLos AngelesCA 90095USA School of Civil Engineering Southeast UniversityNanjing 211102China College of Civil and Transportation Engineering Hohai UniversityNanjing 210024China

A resilience-incorporated risk assessment framework is proposed and demonstrated in this study to manifest the advantageous seismic resilience of precast concrete frame(PCF)structures with“dry”connections in terms of their low damage and rapid *** framework integrates various uncertainties in the seismic hazard,fragility,capacity,demand,loss functions,and post-earthquake *** this study,the PCF structures are distinguished from ordinary reinforced concrete frame(RCF)structures by characterizing multiple limit states for the PCF based on its unique damage ***,probabilistic story-wise pushover analyses are performed to yield story-wise capacities for the predefined limit *** the seismic resilience analysis,a step-wise recovery model is proposed to idealize the functionality recovery process,with separate considerations of the repair and non-repair *** recovery model leverages the economic loss and downtime to delineate the stochastic post-earthquake recovery curves for the resilience loss *** such,contingencies in the probabilistic post-earthquake repairs are incorporated and the empirical judgments on the recovery parameters are largely *** proposed framework is demonstrated through a comparative study between two“dry”connected PCFs and one RCF designed as alternative structural systems for a prototype *** results from the risk quantification indicate that the PCFs show reduced loss hazards and lower expected losses relative to the ***,the PCF equipped with energy dissipation devices at the“dry”connections largely reduces the expected economic loss,downtime,and resilience loss by 29%,56%,and 60%,respectively,compared to the RCF.

关键词： precast concrete frame non-emulative precast system seismic resilience seismic risk functional recovery

The Method of Polynomial Particular Solutions for Solving Nonlinear Poisson-Type Equations

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Acta Mechanica Solida Sinica 2024年第1期37卷 155-165页

作者： Zhile Jia Yanhua cao Xiaoran wu School of Sciences East China Jiaotong UniversityNanchang 330013China

In this paper,the method of polynomial particular solutions is used to solve nonlinear Poisson-type partial differential equations in one,two,and three *** condition number of the coefficient matrix is reduced through the implementation of multiple scale technique,ultimately yielding a stable numerical *** methodological process can be divided into two main parts:first,identifying the corresponding polynomial particular solutions for the linear differential operator terms in the governing equations,and second,employing these polynomial particular solutions as basis function to iteratively solve the remaining nonlinear terms within the governing ***,we investigate the potential improvement in numerical accuracy for equations with singularities in the analytical solution by shifting the computational domain a certain *** experiments are conducted to assess both the accuracy and stability of the proposed method.A comparison of the obtained results with those produced by other numerical methods demonstrates the accuracy,stability,and efficiency of the proposed method in handling nonlinear Poisson-type partial differential equations.

关键词： Nonlinear equation Singularity Polynomial particular solutions Poisson type

Hollow Gradient-Structured Iron-Anchored Carbon Nanospheres for Enhanced Electromagnetic Wave Absorption

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Nano-Micro Letters 2023年第1期15卷 144-160页

作者： cao wu Jing Wang Xiaohang Zhang Lixing Kang Xun cao Yongyi Zhang Yutao Niu Yingying Yu Huili Fu Zongjie Shen Kunjie wu Zhenzhong Yong Jingyun Zou Bin Wang Zhou Chen Zhengpeng Yang Qingwen Li Key Laboratory of Multifunctional Nanomaterials and Smart Systems Advanced Materials DivisionSuzhou Institute of Nano-Tech and Nano-BionicsChinese Academy of SciencesSuzhou 215123JiangsuPeople’s Republic of China School of Science Nanchang Institute of TechnologyNanchang 330099JiangxiPeople’s Republic of China Division of Nanomaterials and Jiangxi Key Lab of Carbonene Materials Jiangxi Institute of NanotechnologyNanchang 330200JiangxiPeople’s Republic of China School of Nano-Tech and Nano-Bionics University of Science and Technology of ChinaHefei 230026AnhuiPeople’s Republic of China School of Materials Science and Engineering Nanyang Technological University50 Nanyang AvenueSingapore 639798Singapore Jiangsu Key Laboratory of Micro and Nano Heat Fluid Flow Technology and Energy Application School of Physical Science and TechnologySuzhou University of Science and TechnologySuzhou 215009People’s Republic of China School of Mechanical and Power Engineering Nanjing Tech UniversityNanjing 211800People’s Republic of China Henan Key Laboratory of Materials On Deep-Earth Engineering School of Materials Science and EngineeringHenan Polytechnic UniversityJiaozuo 454003People’s Republic of China College of Safety Science and Engineering Xi’an University of Science and TechnologyXi’an 710054People’s Republic of China

In the present paper,a microwave absorber with nanoscale gradient structure was proposed for enhancing the electromagnetic absorption *** inorganic-organic competitive coating strategy was employed,which can effectively adjust the thermodynamic and kinetic reactions of iron ions during the solvothermal *** a result,Fe nanoparticles can be gradually decreased from the inner side to the surface across the hollow carbon *** results reveal that it offers an outstanding reflection loss value in combination with broadband wave absorption and flexible adjustment ability,which is superior to other relative graded distribution structures and satisfied with the requirements of lightweight *** addition,this work elucidates the intrinsic microwave regulation mechanism of the multiscale hybrid electromagnetic wave *** excellent impedance matching and moderate dielectric parameters are exhibited to be the dominative factors for the promotion of microwave absorption performance of the optimized *** strategy to prepare gradient-distributed microwave absorbing materials initiates a new way for designing and fabricating wave absorber with excellent impedance matching property in practical applications.

关键词： Gradient structures Carbon nanospheres Electromagnetic wave absorption Impedance matching

Experimental and Numerical Investigation of Non-synchronous Blade Vibration Excitation in a Transonic Axial Compressor

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Journal of Thermal Science 2024年第2期33卷 602-610页

作者： WANG Songbai wu Yadong CHEN Yong cao Zhipeng School of Mechanical Engineering Shanghai Jiao Tong UniversityShanghai200240China AECC Sichuan Gas Turbine Establishment Chengdu610500China

The complex flow phenomenon of rotating instability(RI) and its induced non-synchronous vibration(NSV) have become a significant challenge as they continuously increase aerodynamic *** study aims to provide an understanding of the non-synchronous blade vibration phenomenon caused by the rotating instability of a transonic axial compressor *** this case,blade vibrations and non-synchronous excitation are captured by strain gauges and unsteady wall pressure transducer *** numerical simulations for a full-annulus configuration are used to obtain the non-synchronous flow *** results show that the first-stage rotor blade exhibits an NSV close to the first bending mode;NSV is accompanied by a sharp increase in pressure pulsation;amplitude can reach 20%,and unsteady aerodynamic frequency will lock in a structural mode frequency when the blade vibrates in a large-amplitude *** predicted NSV frequency aligns well with the experimental *** dominant mode of circumferential instability flow structure is approximately 47% of the number blades,and the cell size occupies 2-3 pitches in the circumferential *** full-annulus unsteady simulations demonstrate that the streamwise oscillation of the shedding and reattachment vortex structure is the main cause of NSV owing to the strong interaction between the tip leakage and separation vortices near the suction surface.

关键词： non-synchronous vibration transonic axial compressor rotor blade rotating instabilities unsteady flow

Targeting synaptic pathology in Alzheimer’s disease

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Zoological Research 2024年第4期45卷 875-876页

作者： Jing cao Yun-wu Zhang Fujian Provincial Key Laboratory of Neurodegenerative Disease and Aging Research Institute of NeuroscienceSchool of MedicineXiamen UniversityXiamenFujian 361102China

Alzheimer’s disease(AD)is a neurodegenerative disorder characterized by memory and cognitive *** two primary pathological hallmarks of AD include the accumulation ofβ-amyloid(Aβ)plaques and formation of neurofibrillary tangles(NFTs)composed predominantly of hyperphosphorylated tau protein(Zhang et al.,2023).Moreover,synaptic dysfunction is considered another crucial factor in AD pathogenesis and is closely associated with cognitive ***,synaptic damage,loss,and dysfunction manifest earlier than the pathological features of Aβplaques and NFTs(Knopman et al.,2021).Therefore,understanding the mechanisms underlying synaptic dysfunction in AD is vital for providing insights into disease mechanisms and developing novel therapeutic strategies.

关键词： Alzheimer Aβ tau

Ultrafast optical modulation of the fluorescence from a single-photon emitter in silicon carbide

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Photonics Research 2024年第5期12卷 941-946页

作者： MENGTING HE YUJING cao JUNJIE LIN ZHIPING JU BOTAO wu E wu State Key Laboratory of Precision Spectroscopy East China Normal UniversityShanghai 200241China Photon Technology(Zhejiang)Co. Ltd.Jiaxing 314100China National Key Laboratory of Materials for Integrated Circuits Shanghai Institute of Microsystem and Information TechnologyChinese Academy of SciencesShanghai 200000China Department of Physics and Shanghai Key Laboratory for Magnetic Resonance East China Normal UniversityShanghai 200241China Chongqing Key Laboratory of Precision Optics Chongqing Institute of East China Normal UniversityChongqing 401120China Collaborative Innovation Center of Extreme Optics Shanxi UniversityTaiyuan 030006China

The quest for the room-temperature optical transistor based on nonlinearities in single atoms or molecules is attracting a lot of *** this work,a single-photon emitter in cubic silicon carbide is verified that can operate as an optical switch at room temperature under pulsed green laser illumination with a near-infrared pulsed laser as the control *** demonstrated an ultrafast and reversible optical modulation with a high photoluminescence intensity suppression ratio up to 97.9%and a response time as short as 287.9±5.7 *** current development provides insights for high-precision and ultrafast optical switches,with possibilities for integration with emerging electronic installations to realize more intelligent photoelectric integrated devices.

关键词： emitter carbide photon