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FEM Analysis of Force Parameters During Hot Extrusion Expanding and Reducing Tube Process

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武汉理工大学学报 2006年第S2期28卷 737-740页

作者： WANG Fenghui JIAO anyuan LI Haidong gao Xingqi YANG Siqiong (Anshan University of Science & Technology,Anshan 114044,China Anshan University of Science & Technology Anshan 114044China

In this paper,based on the plastic forming large deformation theory and thermodynamic elastic-plastic FEM,the process of expanding and reducing tube was analyzed by using nonlinear finite element software *** coupled thermal-me- chanical models for the thermal-extrusion tube process were established,and the dynamic simulation to them was carried *** the study on 3 D deformation regulation of the thermal-extrusion tube,the distribution of stress,strain and the curves between the force of extrusion and the distance were *** a result,with only a small quantity of necessary experiments,the select of the schemes and parameters can conveniently be performed in the ***,not only large numbers of experiments can be avoided, but also trial-manufacture period is consumedly shortened and some costs may be *** addition,in order to validate our nu- merical calculation,an experiment of the tube made of 20 steel is presented in this *** agreement is shown between mea- sured and predicted results of the theoretical analysis *** study provides a scientific basis for parametric optimizations of the thermal extrusion expanding and reducing tube production *** the same time,the method used in the present paper has important referential value for studying the similar thermal extrusion parts.

关键词： finite element method thermodynamic couple numerical simulation

Design of highly active and durable oxygen evolution catalyst with intrinsic chlorine inhibition property for seawater electrolysis

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Nano Materials Science 2024年第4期6卷 413-418页

作者： Jieli Chen Xiaodong Shi Suyang Feng Jing Li Xiaohong gao Xiao Wu Ke Li anyuan Qi Chenghang You Xinlong Tian School of Marine Science and Engineering School of Chemical Engineering and Technology Hainan University National Energy Group Ledong Power Generation Co. Ltd

High-efficiency seawater electrolysis is impeded by the low activity and low durability of oxygen evolution catalysts due to the complex composition and competitive side reactions in ***,a heterogeneousstructured catalyst is constructed by depositing NiFe-layered double hydroxides （NiFe-LDH） on the substrate of MXene （V2CTx） modified Ni foam （NF）,and abbreviated as NiFe-LDH/V2CTx/*** demonstrated,owing to the intrinsic negative charge characteristic of V2CTx,chlorine ions are denied entry to the interface between NiFeLDH and V2CTx/NF substrate,thus endowing NiFe-LDH/V2CTx/NF catalyst with high corrosion resistance and durable stability for 110 h at 500 mA ***,the two-dimensional structure and high electrical conductivity of V2CTxcan respectively enlarge the electrochemical active surface area and guarantee fast charge transfer,thereby synergistically promoting the catalytic performance of NiFe-LDH/V2CTx/NF in both deionized water electrolyte (261 m V at 100 m A cm-2) and simulated seawater electrolyte (241 mV at 100 mA cm-2).This work can guide the preparation of oxygen evolution catalysts and accelerate the industrialization of seawater electrolysis.

关键词： NiFe-LDH/V 2 CT x /NF catalyst Oxygen evolution reaction Seawater electrolysis Chlorine inhibition

Networking retinomorphic sensor with memristive crossbar for brain-inspired visual perception

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National Science Review 2021年第2期8卷 74-82页

作者： Shuang Wang Chen-Yu Wang Pengfei Wang Cong Wang Zhu-An Li Chen Pan Yitong Dai anyuan gao Chuan Liu Jian Liu Huafeng Yang Xiaowei Liu Bin Cheng Kunji Chen Zhenlin Wang Kenji Watanabe Takashi Taniguchi Shi-Jun Liang Feng Miao National Laboratory of Solid State Microstructures School of PhysicsCollaborative Innovation Center of Advanced MicrostructuresNanjing University School of Electronic Science and Engineering Nanjing University National Institute for Materials Science

Compared to human vision, conventional machine vision composed of an image sensor and processor suffers from high latency and large power consumption due to physically separated image sensing and processing. A neuromorphic vision system with brain-inspired visual perception provides a promising solution to the problem. Here we propose and demonstrate a prototype neuromorphic vision system by networking a retinomorphic sensor with a memristive crossbar. We fabricate the retinomorphic sensor by using WSe2/h-BN/Al2O3van der Waals heterostructures with gate-tunable photoresponses, to closely mimic the human retinal capabilities in simultaneously sensing and processing images. We then network the sensor with a large-scale Pt/Ta/Hf O2/Ta one-transistor-one-resistor(1 T1 R) memristive crossbar,which plays a similar role to the visual cortex in the human brain. The realized neuromorphic vision system allows for fast letter recognition and object tracking, indicating the capabilities of image sensing, processing and recognition in the full analog regime. Our work suggests that such a neuromorphic vision system may open up unprecedented opportunities in future visual perception applications.

关键词： van der Waals heterostructure retinomorphic sensor memristive crossbar brain-inspired visual perception neuromorphic computing

Design method with controllable velocity direction at throat for inward-turning inlets

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Chinese Journal of Aeronautics 2019年第6期32卷 1403-1415页

作者： Wenyou QIAO anyuan YU Wei gao Weixing WANG Research Center of Combustion Aerodynamics Southwest University of Science and TechnologyMianyang 621010China Jiangsu Province Key Laboratory of Aerospace Power System Nanjing 210016China Science and Technology on Scramjet Laboratory of Hypervelocity Aerodynamics Institute China Aerodynamics Research and Development CenterMianyang 621000China College of Energy and Power Engineering Nanjing University of Aeronautics and AstronauticsNanjing 210016China

In the design of a hypersonic inward-turning inlet by applying the traditional basic flowfield, a reflected shock-wave is formed in the isolator due to the continuous reflection of the cowlreflected shock wave in the basic flow-field, which interacts with the boundary layer to produce a considerable influence on the performance of the inlet. Here, a basic flow-field design method that can control the velocity direction at the throat section is developed, and numerical simulations are conducted to demonstrate the effectiveness of this method. The method presented in this paper can achieve the absorption of the reflected waves at the shoulder of the basic flow-field by adjusting the variation law of the center radius in the basic flow-field, and a smooth transition between the compression surface and the isolator can also be produced. The Mach number and total pressure recovery coefficient of the inlet designed according to this method are 3.00 and 0.657, respectively, at design point(the incoming flow Mach number Ma1= 6.0). The results show that with this method, the inlet can efficiently weaken both the reflection of the shock wave and the interaction between the boundary layer and the reflected shock waves, which improves the aerodynamic performance of the inlet.

关键词： Hypersonic Inverse design Inward-turning inlet Method of characteristic Shock wave

Global consistency check of AIRS and IASI total CO2 column concentrations using WDCGG ground-based measurements

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Frontiers of Earth Science 2017年第1期11卷 1-10页

作者： anyuan DIAO Jiong SHU Ci SONG Wei gao Key Laboratory of Geographic Information Science (Ministry of Education) School of Geographic Sciences East China Normal University Shanghai 200241 China Colorado State University Department of Ecosystem Science and Sustainability Fort Collins Colorado 80523 USA Colorado State University Natural Resource Ecology Laboratory Fort Collins Colorado 80523 USA

This article describes a global consistency check of CO2 satellite retrieval products from the Atmospheric Infrared Sounder （AIRS） and Infrared Atmospheric Sounding Interferometer （IASI） using statistical analysis and data from the World Data Centre for Greenhouse Gases （WDCGG）. We use the correlation coefficient （r）, relative difference （RD）, root mean square errors （RMSE）, and mean bias error （MBE） as evaluation indicators for this study. Statistical results show that a linear positive correlation between AIRS/IASI and WDCGG data occurs for most regions around the world. Temporal and spatial variations of these statistical quantities reflect obvious differences between satellite-derived and ground-based data based on geographic position, especially for stations near areas of intense human activities in the Northern Hemisphere. It is noteworthy that there appears to be a very weak correlation between AIRS/IASI data and ten ground- based observation stations in Europe, Asia, and North America. These results indicate that retrieval products from the two satellite-based instruments studied should be used with great caution.

关键词： CO2 consistency check AIRS IASI WDCGG

Templated synthesis of Ti02 nanotube macrostructures and their photocatalytic properties

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Nano Research 2015年第3期8卷 900-906页

作者： Hongbian Li Qiaoyu Zhou Yuntian gao Xuchun Gui Long Yang Mingde Du Enzheng Shi Jidong Shi anyuan Cao Ying Fang National Center for Nanoscience and Technology 11 Beiyitiao Street Zhongguancun Beijing 100190 China Department of Materials Science and Engineering College of Engineering Peking University Beijing 100871 China State Key Lab of Optoelectronic Materials and Technologies School of Physics and Engineering Sun Yat-sen University Guangzhou 510275 China

Controlled synthesis of hierarchically assembled titanium dioxide （TiO2） nano- structures is important for practical applications in environmental purification and solar energy conversion. We present here the fabrication of interconnected TiO2 nanotubes as a macroscopic bulk material by using a porous carbon nanotube （CNT） sponge as a template. The basic idea is to uniformly coat an amorphous titania layer onto the CNT surface by the infiltration of a TiO2 precursor into the sponge followed by a subsequent hydrolysis process. After calcination, the CNTs are completely removed and the titania is simultaneously crystallized, which results in a porous macrostructure composed of interconnected anatase TiO2 nanotubes. The TiO2 nanotube macrostructures show comparable photocatalytic activities to commercial products （AEROXIDE TiO2 P25） for the degradation of rhodamine B （RhB）. Moreover, the TiO2 nanotube macrostructures can be settled and separated from water within 12 h after photocatalysis, whereas P25 remains suspended in solution after weeks. Thus the TiO2 nanotube macrostructures offer the advantage of easy catalyst separation and recycle and can be a promising candidate for wastewater treatment.

关键词： TiO2 nanotube macrostructure carbon nanotube sponge photocatalysis

固相萃取-气质色谱联用法测定PVC管材中邻苯二甲酸酯类增塑剂的含量

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聚氯乙烯 2017年第9期45卷 38-41页

作者：刘妍妍姜祖波郭兵林凤章赵秀平陈安源高建国孙卓军青岛市黄岛区食品药品监督管理局山东青岛266500 青岛双桃精细化工(集团)有限公司山东青岛266031 山东出入境检验检疫局检验检疫技术中心山东青岛266002 青岛出入境检验检疫局山东青岛266001

通过试验研究萃取剂、萃取方式等样品的前处理条件,建立了一种固相萃取-气质色谱联用测定PVC管材中10余种邻苯二甲酸酯类增塑剂环境激素含量的方法,填补了PVC管材检测在此领域的空白。

关键词：固相萃取气质色谱联用邻苯二甲酸酯环境激素 PVC管材

扫描速度对300M钢熔覆C276涂层组织及性能的影响

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红外与激光工程 2023年第1期52卷 99-107页

作者：杨广峰郜峰崔静薛安源中国民航大学航空工程学院天津300300 中国民航大学交通科学与工程学院天津300300 上海理工大学能源与动力工程学院上海200093

为了提升300M超高强度钢表面的耐蚀性能,在300M钢表面通过激光熔覆技术制备出四组扫描速度分别为5 mm/s,8 mm/s,11 mm/s和14 mm/s的涂层试样,通过光学显微镜、扫描电镜、X射线衍射仪、EDS能谱仪、显微硬度仪、摩擦磨损机、电化学工作站... 详细信息

为了提升300M超高强度钢表面的耐蚀性能,在300M钢表面通过激光熔覆技术制备出四组扫描速度分别为5 mm/s,8 mm/s,11 mm/s和14 mm/s的涂层试样,通过光学显微镜、扫描电镜、X射线衍射仪、EDS能谱仪、显微硬度仪、摩擦磨损机、电化学工作站仪器分别表征涂层的宏观形貌、显微组织、物相组成、元素分布、硬度性能、摩擦磨损性能和耐腐蚀性能。结果表明,300M钢熔覆C276后,涂层的耐蚀性和硬度都得到增强,但耐磨性能较原基体变差,涂层形貌受扫描速度的影响,扫描速度越大,平整度越趋于平整,且金属光泽也逐渐加深,同时在不同参数下的涂层物相种类未发生明显变化,主相均为Ni-Cr-Co-Mo,在扫描速度8 mm/s的参数下,涂层具有最高的硬度较基体提升约36.2%,同时也具有更佳的耐蚀性能与其他力学性能。

关键词：激光熔覆显微组织硬度摩擦磨损性能耐蚀性能

电磁搅拌对TiB2颗粒增强钢组织和力学性能的影响

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金属学报 2020年第9期56卷 1239-1246页

作者：张林郭晓高建文邓安元王恩刚东北大学材料电磁过程研究教育部重点实验室沈阳110819 东北大学冶金学院沈阳110819

在立式线型电磁搅拌器的作用下凝固制备TiB2颗粒增强钢,研究了电磁搅拌对组织中的颗粒形态和尺寸分布,以及对材料的Vickers硬度分布和拉伸力学性能的影响。结果表明,电磁搅拌有效地细化了颗粒增强钢中的初生TiB2颗粒尺寸,颗粒平均尺寸... 详细信息

在立式线型电磁搅拌器的作用下凝固制备TiB2颗粒增强钢,研究了电磁搅拌对组织中的颗粒形态和尺寸分布,以及对材料的Vickers硬度分布和拉伸力学性能的影响。结果表明,电磁搅拌有效地细化了颗粒增强钢中的初生TiB2颗粒尺寸,颗粒平均尺寸随励磁电流的上升而逐步减小。较高的励磁电流下颗粒的分布更均匀弥散,且去除了颗粒周围的裂缝缺陷。电磁搅拌降低了TiB2颗粒增强钢的宏观偏析,减小了铸锭中不同高度组织的硬度差。较大的励磁电流有助于提高材料的平均硬度,在350 A励磁电流下硬度达到275 HV。电磁搅拌可提高TiB2颗粒增强钢的抗拉强度和断裂应变,励磁电流为350 A时,抗拉强度达到520.2 MPa,断裂应变约为8.5%。颗粒细化的主要原因是受到电磁搅拌下的熔体流动冲击和电磁力的作用。理论分析了颗粒所受电磁力的影响因素,电磁力随磁场强度升高而增大,随熔体温度的上升而减小,随颗粒尺寸的增加而增大。

关键词：电磁搅拌 TiB2颗粒增强钢硬度抗拉强度