威尼斯娱人城官网

Sep.2008-Apr.2012, Shanghai Jiao Tong University, Doctor
Sep.2006-Apr.2008, Shanghai Jiao Tong University, Master
Sep.2002-Jun.2006, Shanghai Jiao Tong University, Bachelor

2016-Now, Associate Professor (Ph.D. Supervisor), School of Mechanical Engineering, Shanghai Jiao Tong University
2014-2015, Lecturer, School of Mechanical Engineering, Shanghai Jiao Tong University;
2012-2014, Post Doctoral Research Assistant, Shanghai Jiao Tong University;

2013-2013, Visiting Scholar, Wu Xianming Manufacturing Research Center, University of Michigan
2007-2008, Exchange Visiting Students, College of Engineering, University of Michigan

Micro/Meso-scale Modeling Method;
Micro forming process and Polar Plate of Fuel Cell Forming Process;
Functional Micro-Structure Surface Roll-to Roll Forming Process;
Flexible Electronics Manufacturing Technology.

2017-2020 “Study on Scale Effect and Process Rule of Flexible Transparent Electrode Roll-to-Roll Stamping”, General Program of The National Natural Science Foundation of China, Person in Charge
2018-2022 "Basic Research of XXX Key Technology ", Defense Basic Strengthening Plan of National Key Basic Research Program of China (Former National Defense 973 Program), Subject Leader.
2018-2021 "Antifriction Mechanism and Sputtering Process of Solid Lubricating Coating for Aerospace Pyrotechnic Separation", Key Project of China Aerospace Science and Technology Corporation Aerospace Advanced Manufacturing Technology Research Joint Fund, National Natural Science Foundation of China, Subject Leader.
2017-2021 "Development of High Performance and Long Life Engine of the Fuel Cell System.", National Key R&D Program of China, Person in Charge in Shanghai Jiaotong University
2017-2019 "Multi-Step Forming and Precision Blanking Combined Processing Technology of XXX Butterfly Diaphragm ", Equipment Pre-Research-Aerospace Technology Joint Fund, Person in Charge
2014-2016 "Mechanical Behavior Modeling and Forming Process of Layer Structure in Fuel Cell Metal Gas Diffusion ", Youth Program of the National Natural Science Foundation of China, Person in Charge
2013-2015 "Technology of Low Platinum and High Performance Automotive Fuel Cell Stack-Precision Stamping of Metal Bipolar Plates", Sub-program of National High-tech R&D Program (863 Program), Person in Charge
2015-2016 CALT Space Fund, Person in Charge
2015-2016 "Study on Water and Gas Transmission Characteristics in Fuel Cell Dynamic Loading and Unloading Processing", SAIC Fund, Person in Charge
2014-2016 “Mesoscopic Mesoscale Contact Mechanism and Cascading Assembly Modeling for Fuel Cells”, “Dawn Light Project” in Shanghai, Person in Charge
2014-2016 “SMC Dawn Light Young Scholars Award Scheme” of Shanghai Jiaotong University, Type B, Person in Charge
2014-2017 New Scientific Research Foundation for Young Teachers of Shanghai Jiaotong University, Person in Charge
2014-2015 “Research on Metal Fuel Cell Plate”, Crosswise Task of Wuhan WUT New Energy Company, Person in Charge
2014-2015 "Fuel Cell Stack", Task of Shanghai Sunrise Power Company, Person in Charge
2013-2014 The Sixth Batch of Special Funded Project, China Postdoctoral Science Fund, Person in Charge
2012-2014 The Fifty-Second Batch of Projects Funded, China Postdoctoral Science Fund, Person in Charge
2013-2014 Shanghai Postdoctoral Research Funding Program (Type A), Person in Charge
2013-2017 "Mesoscopic Scale Effect of Continuous Hot Roll Forming of Thin Film Surface and its New Method of Shape Control", the State Key Program of National Natural Science Foundation of China, Project participants
2009-2012 "Technology and Theoretical Basic Research of Proton Exchange Membrane Fuel Cell Stack Plate Manufacturing and Assembling ", Projects of International Cooperation and Exchanges NSFC, Project participants
2013-2014 "Manufacturing Technology Development of Fuel Battery Metal Plate ", Shanghai Automotive Industry (Group) Corporation, Project participants

2018
[61] Yi Peiyun, Zhang Di, Peng Linfa, Lai Xinmin. Impact of Film Thickness on Defects and the Graphitization of Nanothin Carbon Coatings Used for Metallic Bipolar Plates in Proton Exchange Membrane Fuel Cells. ACS Applied Materials & Interfaces. 2018.
[60] Yi Peiyun, Zhang Weixin, Bi Feifei, Peng Linfa, Lai Xinmin. Enhanced Corrosion Resistance and Interfacial Conductivity of TiCx/a-C Nanolayered Coatings via Synergy of Substrate Bias Voltage for Bipolar Plates Applications in PEMFCs. ACS Applied Materials & Interfaces. 2018;10:19087–96.
[59] Yi Peiyun, Deng Yujun, Shu Yunyi, Peng Linfa. Experimental studies on a novel roll-to-roll powder hot embossing for large-area fabrication of micropyramid arrays on polymers. Journal of Micromechanics and Microengineering, 2018;28:085007.
[58] Weixin Zhang, Peiyun Yi, Linfa Peng, Xinmin Lai. Strategy of alternating bias voltage on corrosion resistance and interfacial conductivity enhancement of TiCx/a-C coatings on metallic bipolar plates in PEMFCs. Energy. 2018;162:933-43.
[57] Diankai Qiu, Linfa Peng, Peiyun Yi, Xinmin Lai, Werner Lehnert. Flow channel design for metallic bipolar plates in proton exchange membrane fuel cells: Experiments. Energy Conversion and Management. 2018;174:814-23.
[56] Qiu Diankai, Peng Linfa, Liang Peng, Yi Peiyun, Lai Xinmin. Mechanical degradation of proton exchange membrane along the MEA frame in proton exchange membrane fuel cells. Energy. 2018.
[55] Liang Peng, Qiu Diankai, Peng Linfa, Yi Peiyun, Lai Xinmin, Ni Jun. Contact resistance prediction of proton exchange membrane fuel cell considering fabrication characteristics of metallic bipolar plates. Energy Conversion and Management 2018, 169:334-44.
[54] Huang Jihui, Deng Yujun, Yi Peiyun, Peng Linfa. Experimental and numerical investigation on thin sheet metal roll forming process of micro channels with high aspect ratio. The International Journal of Advanced Manufacturing Technology. 2018.

2017
[53] Yi Peiyun, Zhang Chengpeng, Peng Linfa, Lai Xinmin, Flexible silver-mesh electrodes with moth-eye nanostructures for transmittance enhancement by double-sided roll-to-roll nanoimprint lithography. RSC Advances 2017, 7 (77), 48835-48840.
[52] Zhang Chengpeng, Yi Peiyun*, Peng Linfa, Lai Xinmin, Chen Jie, Huang Meizhen, Ni Jun. Continuous fabrication of nanostructure arrays for flexible surface enhanced Raman scattering substrate. Scientific Reports 2017;7:39814.
[51] Zhang Chengpeng, Yi Peiyun*, Peng Linfa, Ni Jun. Optimization and continuous fabrication of moth-eye nanostructure array on flexible polyethylene terephthalate substrate towards broadband antireflection. Applied Optics 2017;56:2901-2907.
[50] Wang Zhaozhao, Yi Peiyun*, Peng Linfa, Lai Xinmin, Ni Jun. Continuous Fabrication of Highly Conductive and Transparent Ag Mesh Electrodes for Flexible Electronics. IEEE Transactions on Nanotechnology 2017.
[49] Wang Jin, Yi Peiyun*, Deng Yujun, Peng Linfa, Lai Xinmin, Ni Jun. Recovery behavior of thermoplastic polymers in micro hot embossing process. Journal of Materials Processing Technology 2017;243:205-216.
[48] Qiu Diankai, Peng Linfa, Yi Peiyun, Lai Xinmin. A micro contact model for electrical contact resistance prediction between roughness surface and carbon fiber paper. International Journal of Mechanical Sciences 2017;124:37-47.
[47] Liang Peng, Qiu Diankai, Peng Linfa, Yi Peiyun, Lai Xinmin, Ni Jun. Structure failure of the sealing in the assembly process for proton exchange membrane fuel cells. International Journal of Hydrogen Energy 2017;42:10217-10227.
[46] Li Wenjun, Song Shiqiang, Zhai Yinghao, Zhang Yong, Yi Peiyun, Lai Xinmin. Rheological behavior of ethylene-vinyl acetate copolymer and fabrication of micropyramid arrays by roll-to-roll hot embossing on its thin films. Journal of Applied Polymer Science 2017;134.
[45] Jiang Tianhao, Peng Linfa, Yi Peiyun, Lai Xinmin. Investigation of Deformation Behavior of SS304 and Pure Copper Subjected to Electrically Assisted Forming Process. Journal of Manufacturing Science and Engineering 2017;139:011004.
[44] Chengpeng Zhang, Yuwen Zhu, Peiyun* Yi, Linfa Peng, Xinmin Lai. Fabrication of flexible silver nanowire conductive films and transmittance improvement based on moth-eye nanostructure array. Journal of Micromechanics and Microengineering 2017;27:075010.
[43] Bi Feifei, Li Xiaobo, Yi Peiyun*, Hou Kun, Peng Linfa, Lai Xinmin. Characteristics of amorphous carbon films to resist high potential impact in PEMFCs bipolar plates for automotive application. International Journal of Hydrogen Energy 2017;42:14279-14289.
[42] Bi Feifei, Hou Kun, Yi Peiyun, Peng Linfa, Lai Xinmin. Mechanisms of growth, properties and degradation of amorphous carbon films by closed field unbalanced magnetron sputtering on stainless steel bipolar plates for PEMFCs. Applied Surface Science 2017.

2016
[41] Yi Peiyun, Peng Linfa, Huang Jiaqiang. Multilayered TiAlN films on Ti6Al4V alloy for biomedical applications by closed field unbalanced magnetron sputter ion plating process. Materials Science and Engineering: C 2016;59:669-676.
[40] Wu Hao, Yi Peiyun, Peng Linfa, Lai Xinmin. Study on bubble defects in roll-to-roll UV imprinting process for micropyramid arrays. I. Experiments. Journal Of Vacuum Science & Technology B 2016;34:021201.
[39] Zhao Yong, Wei Lin, Yi Peiyun, Peng Linfa. Influence of Cr-C film composition on electrical and corrosion properties of 316L stainless steel as bipolar plates for PEMFCs. International Journal Of Hydrogen Energy 2016;41:1142-1150.
[38] Xu Yifan, Peng Linfa, Yi Peiyun, Lai Xinmin. Analysis of the flow distribution for thin stamped bipolar plates with tapered channel shape. International Journal Of Hydrogen Energy 2016;41:5084-5095.
[37] Mao Mengyun, Peng Linfa, Yi Peiyun, Lai Xinmin. Modeling of the Friction Behavior in Metal Forming Process Considering Material Hardening and Junction Growth. Journal Of Tribology-transactions Of The Asme 2016;138:012202-012202.
[36] Jiang Tianhao, Peng Linfa, Yi Peiyun, Lai Xinmin. Analysis of the Electric and Thermal Effects on Mechanical Behavior of SS304 Subjected to Electrically Assisted Forming Process. Journal of Manufacturing Science and Engineering 2016;138:061004-061004.
[35] Bi Feifei, Peng Linfa, Yi Peiyun, Lai Xinmin. Multilayered Zr–C/a-C film on stainless steel 316L as bipolar plates for proton exchange membrane fuel cells. Journal Of Power Sources 2016;314:58-65.

2015
[34] Yi PeiYun, Peng LinFa & Lai XinMin. Recent progress in fabrication methods for micro structures on optical thin film. Chinese Science Bulletin 2015;60:2707-2718.
[33] Yi Peiyun, Wu Hao, Zhang Chengpeng, Peng Linfa, Lai Xinmin. Roll-to-roll UV imprinting lithography for micro/nanostructures. AIP-Journal of Vacuum Science & Technology B 2015;33:060801.
[32] Yi Peiyun , Shu Yunyi , Deng Yujun , Peng Linfa , Lai Xinmin Mechanism of forming defects in roll-to-roll hot embossing of micro-pyramid arrays I: experiments. IOP-Journal of Micromechanics and Microengineering 2015;25:105017.
[31] Yi Peiyun, Du Xiangyong, Kan Yuyan, Peng Linfa, Lai Xinmin. Modeling and experimental study of laser welding distortion of thin metallic bipolar plates for PEM fuel cells. International Journal Of Hydrogen Energy 2015;40:4850-4860.
[30] Zhang C., Yi P., Peng L., Lai X., Ni J. Fabrication of Moth-eye Nanostructure Arrays using roll-to-roll UV-Nanoimprint Lithography with an Anodic Aluminum Oxide mold. Nanotechnology-IEEE Transactions 2015;PP:1127-1137.
[29] Wang Jin, Yi Peiyun, Deng Yujun, Peng Linfa, Lai Xinmin, Ni Jun. Mechanism of forming defects in roll-to-roll hot embossing of micro-pyramid arrays: II. Numerical study. Journal Of Micromechanics And Microengineering 2015;25:115030.
[28] Qiu Diankai, Yi Peiyun, Peng Linfa, Lai Xinmin. Channel Dimensional Error Effect of Stamped Bipolar Plates on the Characteristics of Gas Diffusion Layer Contact Pressure for Proton Exchange Membrane Fuel Cell Stacks. Journal of Fuel Cell Science and Technology-Transactions of the ASME 2015;12:041002-041002.
[27] Qiu Diankai, Yi Peiyun, Peng Linfa, Lai Xinmin. Assembly design of proton exchange membrane fuel cell stack with stamped metallic bipolar plates. International Journal Of Hydrogen Energy 2015;283:429-442.
[26] Peng Linfa, Yi Peiyun, Hu Peng, Lai Xinmin, Ni Jun. Analysis of Micro/Mesoscale Sheet Forming Process by Strain Gradient Plasticity and Its Characterization of Tool Feature Size Effects. Journal of Micro and Nano-Manufacturing 2015;3:011006-011006.
[25] Gao Zhaoyang, Peng Linfa, Yi Peiyun, Lai Xinmin. Grain and geometry size effects on plastic deformation in roll-to-plate micro/meso-imprinting process. Journal Of Materials Processing Technology 2015;219:28-41.
[24] Deng Yujun, Peiyun Yi, Linfa Peng, Xinmin Lai, Zhongqin Lin. Flow behavior of polymers during the roll-to-roll hot embossing process. Journal Of Micromechanics And Microengineering 2015;25:065004.
[23] Bi Feifei, Yi Peiyun, Zhou Tao, Peng Linfa, Lai Xinmin. Effects of Al incorporation on the interfacial conductivity and corrosion resistance of CrN film on SS316L as bipolar plates for proton exchange membrane fuel cells. International Journal Of Hydrogen Energy 2015;40:9790-9802.

2014
[22] Steven Peters, Gisela Lanza, Ni Jun, Jin Xiaoning, Yi PeiYun, Marcello Colledani. Automotive manufacturing technologies-an international viewpoint. Manufacturing Review 2014;1:1-12.
[21] Peng Linfa, Yi Peiyun, Lai Xinmin. Design and manufacturing of stainless steel bipolar plates for proton exchange membrane fuel cells. International Journal Of Hydrogen Energy 2014;39:21127-21153.
[20] Peng Linfa, Yi Peiyun, Hu Peng, Lai Xinmin, Ni Jun. Analysis of the Micro/Meso Scale Sheet Forming by Strain Gradient Plasticity and its Characterization of Tool Feature Size Effects. ASME 2014 International Manufacturing Science and Engineering Conference collocated with the JSME 2014 International Conference on Materials and Processing and the 42nd North American Manufacturing Research Conference: American Society of Mechanical Engineers; 2014. p. V001T003A006-V001T003A006.
[19] Peng Linfa, Deng Yujun, Yi Peiyun, Lai Xinmin. Micro hot embossing of thermoplastic polymers: a review. Journal Of Micromechanics And Microengineering 2014;24:013001.
[18] Deng Yujun, Yi Peiyun, Peng Linfa, Lai Xinmin, Lin Zhongqin. Experimental investigation on the large-area fabrication of micro-pyramid arrays by roll-to-roll hot embossing on PVC film. Journal Of Micromechanics And Microengineering 2014;24:045023.

2013
[17] Yi Peiyun, Peng Lin Fa, Zhou Tao, Wu Hao, Lai Xin Min. Cr–N–C multilayer film on 316L stainless steel as bipolar plates for proton exchange membrane fuel cells using closed field unbalanced magnetron sputter ion plating. International Journal Of Hydrogen Energy 2013;38:1535-1543.
[16] Yi Peiyun, Peng Linfa, Zhou Tao, Wu Hao, Lai Xinmin. Development and characterization of multilayered Cr–C/a-C:Cr film on 316L stainless steel as bipolar plates for proton exchange membrane fuel cells. Journal Of Power Sources 2013;230:25-31.
[15] Yi Peiyun, Peng Linfa, Zhou Tao, Huang Jiaqiang, Lai Xinmin. Composition optimization of multilayered chromium-nitride–carbon film on 316L stainless steel as bipolar plates for proton exchange membrane fuel cells. Journal Of Power Sources 2013;236:47-53.
[14] Yi Peiyun, Peng Linfa, Liu Ning, Lai Xinmin, Ni Jun. A micromechanics elastic–plastic constitutive model for sintered stainless steel fiber felt. Materials & Design 2013;51:876-885.
[13] Qiu Diankai, Yi Peiyun, Peng Linfa, Lai Xinmin. Study on shape error effect of metallic bipolar plate on the GDL contact pressure distribution in proton exchange membrane fuel cell. International Journal Of Hydrogen Energy 2013;38:6762-6772.
[12] Gao Zhao Yang, Peng Lin Fa, Yi Pei Yun, Lai Xin Min. Micro/Meso Roll-to-Plate (R2P) Imprinting Process to Fabricate Micro Channel/Riblet Features. Applied Mechanics and Materials2013. p. 611-616.
[11] Gao Zhaoyang, Peng Linfa, Yi Peiyun, Lai Xinmin. Modeling and size effect analysis of micro/meso roll-to-plate imprinting process. Jixie Gongcheng Xuebao(Chinese Journal of Mechanical Engineering) 2013;49:179-186.
[10] Gao Zhaoyang, Peng Linfa, Yi Peiyun, Lai Xinmin. An Experimental Investigation on the Fabrication of Micro/Meso Surface Features by Metallic Roll-to-Plate Imprinting Process. Journal of Micro and Nano-Manufacturing-Transactions of the ASME 2013;1:031004-031004.

2012
[9] Yi Peiyun, Peng Linfa, Lai Xinmin, Lin Zhongqin, Ni Jun. Performance Improvement of Wave-Like PEMFC Stack with Compound Membrane Electrode Assembly. Fuel Cells 2012;12:1019-1026.
[834] Yi PeiYun , Peng LinFa, Lai XinMin, Li MuTian, Ni Jun. Investigation of sintered stainless steel fiber felt as gas diffusion layer in proton exchange membrane fuel cells. International Journal Of Hydrogen Energy 2012;37:11334-11344.
[7] Xu Zhutian, Peng Linfa, Yi Peiyun, Lai Xinmin. Study on a Novel Electrical-Assisted Pressure Welding Process of Thin Metallic Foils. Applied Mechanics and Materials 2012;271-272:147-151.
[6] Xu Zhutian, Peng Linfa, Yi Peiyun, Lai Xinmin. Modeling of Microchannel Hydroforming Process With Thin Metallic Sheets. Journal Of Engineering Materials And Technology-transactions Of The Asme 2012;134:021017-021013.
[5] Peng Lin Fa, Qiu Dian Kai, Yi Pei Yun, Lai Xin Min. Investigation of Thermal Influence on the Assembly of Polymer Electrolyte Membrane Fuel Cell Stacks. Advanced Materials Research2012. p. 1509-1514.

2011
[4] Yi Peiyun, Peng Linfa, Lai Xinmin, Ni Jun. A Numerical Model for Predicting Gas Diffusion Layer Failure in Proton Exchange Membrane Fuel Cells. Journal of Fuel Cell Science and Technology-Transactions of the ASME 2011;8:011011-011010.
[3] Peng Lin Fa, Lai Xin Min, Yi Pei Yun, Mai Jian Ming. Design, Optimization, and Fabrication of Slotted-Interdigitated Thin Metallic Bipolar Plates for PEM Fuel Cells. Journal of Fuel Cell Science and Technology-Transactions of the ASME 2011;8:011002.

2010
[2] Yi Peiyun, Peng Linfa, Lai Xinmin, Liu Dongan, Ni Jun. A Novel Design of Wave-Like PEMFC Stack with Undulate MEAs and Perforated Bipolar Plates. Fuel Cells 2010;10:111-117.
[1] Yi Peiyun, Peng Linfa, Feng Lizhong, Gan Pin, Lai Xinmin. Performance of a proton exchange membrane fuel cell stack using conductive amorphous carbon-coated 304 stainless steel bipolar plates. Journal Of Power Sources 2010;195:7061-7066.

Engineering Materials, Undergradutes,Cridet 3;
Manufacturing Technology,Undergradutes,Cridet 4;

[1] A method for producing a proton exchange membrane fuel cell stack, Patent No.：ZL 200710043435.4
[2]. Proton exchange membrane fuel cell bipolar plates that based on sheet metal forming, Patent No.: ZL 200710044479.9
[3]. Composite manufacturing method of bipolar plate and membrane electrode assembling for proton exchange membrane fuel cell, Patent No.: ZL 200910049005.2
[4]. Metal gas diffusion layer for fuel cell and its preparation method, Patent No.: ZL 201010605127.8
[5].Automated assembly device for fuel cell stack, Patent No.: ZL 201110065618.2
[6].A micro imprinting device with fully hydraulically driven roller system, Patent No.: ZL 201210049165.9
[7].A micro-structure roll-to-roll hot forming device for polymer film products, Patent No.: ZL 201210208492.4
[8]. Fuel cell metal bipolar plate with conductive corrosion resistant coating and its preparation method, Patent No.: ZL 201210438569.7
[9]. Film processing apparatus and method of roll-to-roll hot forming process for polymer surface microstructure, Patent No.: ZL 201210292620.8
[10].A large-area metal bipolar plate for a fuel cell of vehicle, Patent No.: ZL 201210509907.1
[11].A continuous metal stamping mold for large-area metal bipolar plates of fuel cell, Patent No.: ZL 201310051905.7
[12].A device and measuring method of friction measuring, Patent No.: ZL201510224903.2
[13]. Method for manufacturing additive of functionally graded parts based on three-dimensional heterogeneous paving, Patent No.: ZL201510088107.0
[14].A multi-section clamping adaptive laser welding fixture of ultra-thin metal bipolar plate, Patent No.: ZL201410122678.7
[15].A UV curing forming device that based on roll-to-roll strip mold for double-sided microstructure of polymer film, Patent No.: ZL201310681917.8
[16].A automation assembly system for proton exchange membrane of fuel cell stack, Patent No.: ZL201510225541.9
[17]. Graphene composite coating for fuel cell metal plate and its preparation method, Patent No.: 201510399192.2
[18].A forming method and a device for metal powder electric auxiliary with micro channel structure, Patent No.: 201510594073.2
[19]. Reflective film with moth-eye structure and its preparation process, Patent No.: 201510866506.5
[20]. Surface vapor-deposited aluminum anti-slip film with anti-reverse performance and its preparation process. Patent No.: 201610120356.8
[21]. A Nanopore-structure omnidirectional anti-spy film and its manufacturing process, Patent No.: 201610120721.5

2017 First Prize of Chinese Automotive Industry Technology Invention Award (Top 5)
2015 First Prize of Education Nature Award by Chinese Ministry of Education (Top 4)
2015 Excellent Advisor Teacher for Bachelor's Degree Thesis of Shanghai Jiaotong University, （TOP1%）
2014 Member of “Dawn light Program” in Shanghai
2014 “SMC Dawn Light Young Scholars Award Scheme”of Shanghai Jiaotong University, Type B
2014 The first batch of College Students in the“Xiaoping Technology Innovation Team”, Responsible person
2014 Excellent Doctoral Dissertation Award of Shanghai
2013 Bronze Award of Hiwin Doctoral Dissertation Award
2010 Scholarship Award for Excellent Doctoral Student granted by Chinese Ministry of Education (Total 700/Whole Country)
2012 Excellent Graduates of Shanghai

2016 Excellent Teacher of Shanghai Jiaotong University
2015 Excellent Class Sponsor of Shanghai Jiaotong University
2011 Excellent Communist Party Member by Shanghai Education and Health Party Committee
2010 Ten "Three good" Student Model of SJTU (Total 10 in SJTU)
2010 “Touching ShangHai Jiaotong University” Campus News Person
2008 Excellent Individual of Social Practice in Shanghai