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A comprehensive review of the modeling of transport phenomenon in the flow channels of polymer electrolyte membrane fuel cells

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Frontiers of Chemical Science and Engineering 2024年第8期18卷 123-161页

作者： Niyi Olukayode Shenrong Ye Mingruo Hu Yanjun Dai Rui Chen sheng sui Institute of Fuel Cell Shanghai Jiao Tong UniversityShanghai 200240China Institute of Refrigeration and Cryogenics Shanghai Jiao Tong UniversityShanghai 200240China Low Carbon Engineering Loughborough UniversityLoughborough Leicestershire LE113TUUK

Reactant gas and liquid water transport phenomena in the flow channels are complex and critical to the performance and durability of polymer electrolyte membrane fuel *** polymer membrane needs water at an optimum level for proton *** management involves the prevention of dehydration,waterlogging,and the cell’s subsequent performance decline and *** process requires the study and understanding of internal two-phase *** experimental visualization techniques are used to study two-phase flows in polymer electrolyte membrane fuel ***,the experiments have limitations in in situ measurements;they are also expensive and time *** contrast,numerical modeling is cheaper and faster,providing insights into the complex multiscale processes occurring across the components of the polymer electrolyte membrane fuel *** paper introduces the recent design of flow *** reviews the numerical modeling techniques adopted for the transport phenomena therein:the two-fluid,multiphase mixture,volume of fluid,lattice Boltzmann,and pressure drop ***,this work describes,compares,and analyses the models’approaches and reviews the representative results of some selected ***,the paper summarizes the modeling perspectives,emphasizing future directions with some recommendations.

关键词： two-phase flows numerical model flow channel polymer electrolyte membrane fuel cells water management

Linearity optimization of edge filter demodulators in FBG_s

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Optoelectronics Letters 2008年第3期4卷 193-195页

作者： LI Dong-sheng sui Qing-mei CAO Yu-qiang Optical Fiber Sensor Technology and Engineering Research Center Shandong University Jinan 250061 China

A kind of electric circuit is improved to optimize the linearity of edge filter demodulators in FBG .By using a logarithm amplifier and an extraction operation, the linear range of optimized edge filter demodulators has been broadened effectively, and the requirement of optical filter＇s linear range has been reduced. Theoretical analyses and the simulation results indi-cated that the linear range of optimized edge fdter demodulator＇s covers the whole transition region of the edge filter, while a strict linearity of the optical filter is not necessary.

关键词：光纤解调器线性分析分析方法

Cathode Design for Proton Exchange Membrane Fuel Cells in Automotive Applications

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Automotive Innovation 2021年第2期4卷 144-164页

作者： Haojie Wang Ruiqing Wang sheng sui Tai Sun Yichang Yan Shangfeng Du School of Mechanical and Power Engineering East China University of Science and TechnologyShanghai 200237China Institute of Fuel Cells Shanghai Jiao Tong UniversityShanghai 200240China Research Institute of Rare Metals Guangdong Academy of SciencesGuangzhou 510650GuangdongChina School of Chemical Engineering University of BirminghamBirmingham B152TTUK

An advanced cathode design can improve the power performance and durability of proton exchange membrane fuel cells(PEMFCs),thus reducing the stack cost of fuel cell vehicles(FCVs).Recent studies on highly active Pt alloy catalysts,short-side-chain polyfluorinated sulfonic acid(PFSA)ionomer and 3D-ordered electrodes have imparted PEMFCs with boosted power *** achieve the compacted stack target of 6 kW/L or above for the wide commercialization of FCVs,developing available cathodes for high-power-density operation is critical for the ***,current developments still remain extremely challenging with respect to highly active and stable catalysts in practical operation,controlled distribution of ionomer on the catalyst surface for reducing catalyst poisoning and oxygen penetration losses and 3D(three-dimensional)-ordered catalyst layers with low Knudsen diffusion losses of oxygen *** review paper focuses on impacts of the cathode development on automotive fuel cell systems and concludes design directions to provide the greatest benefit.

关键词： Fuel cell vehicle(FCV) Proton exchange membrane fuel cell(PEMFC) Cathode Mass transport Ionomer

A maximum power point tracker for photovoltaic energy systems based on fuzzy neural networks

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2009年第2期10卷 263-270页

作者： Chun-hua LI Xin-jian ZHU Guang-yi CAO Wan-qi HU sheng sui Ming-ruo HU Fuel Cell Research Institute Shanghai Jiao Tong University Shanghai 200240. China Institute of Process Engineering Chinese Academy of Sciences Beijing 100080 China

To extract the maximum power from a photovoltaic （PV） energy system, the real-time maximum power point （MPP） of the PV array must be tracked closely. The non-linear and time-variant characteristics of the PV array and the non-linear and non-minimum phase characteristics of a boost converter make it difficult to track the MPP for traditional control strategies. We propose a fuzzy neural network controller （FNNC）, which combines the reasoning capability of fuzzy logical systems and the learning capability of neural networks, to track the MPP. With a derived learning algorithm, the parameters of the FNNC are updated adaptively. A gradient estimator based on a radial basis function neural network is developed to provide the reference information to the FNNC. Simulation results show that the proposed control algorithm provides much better tracking performance compared with the filzzy logic control algorithm.

关键词： Photovoltaic array Maximum power point tracking (MPPT) Fuzzy neural network controller (FNNC) Radial basis function neural network (RBFNN)

Carbon matrix effects on the micro-structure and performance of Pt nanowire cathode prepared by decal transfer method

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Journal of Energy Chemistry 2015年第2期24卷 213-218页

作者： Zhaoxu Wei An He Kaihua Su sheng sui Institute of Fuel Cell Shanghai Jiao Tong University

High performance cathode for polymer electrolyte membrane fuel cell was prepared by depositing Pt nanowires in a carbon matrix coated on a substrate, and using decal transfer method to fabricate the membrane electrode assembly. The effects of carbon and ionomer contents on the electrode micro-structure and fuel cell performance are investigated by physical characterization and single cell testing. The Pt nanowires are gradient distributed across the cathode thickness, and more Pt exists near the membrane. Both the carbon and ionomer contents can affect the Pt nanowires distribution and aggregation. In addition, the carbon loading dominates the transport distance of gas and proton, and the ionomer content affects the triple phase boundaries and porosity in the cathode. The optimal structure of Pt nanowire cathode is obtained at 0.10 mg·cm^-2 carbon loading and 10 wt% ionomer.

关键词： Pt nanowire carbon matrix ionomer decal transfer method polymer electrolyte membrane fuel cell

Corrosion resistance and mechanisms of smart micro-arc oxidation/epoxy resin coatings on AZ31 Mg alloy: Strategic positioning of nanocontainers

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Journal of Magnesium and Alloys 2023年第12期11卷 4562-4574页

作者： Ai-meng Zhang Chengbao Liu Pu-sheng sui Cong Sun Lan-yue Cui M.Bobby Kannan Rong-Chang Zeng College of Materials Science and Engineering Shandong University of Science and TechnologyQingdao 266590China School of Materials Science and Engineering Zhengzhou UniversityZhengzhou 450002China School of Engineering University of NewcastleCallaghanNew South Wales 2308Australia

Smart micro-arc oxidation(MAO)/epoxy resin(EP) composite coatings were formed on AZ31 magnesium(Mg) alloy. Mesoporous silica nanocontainers(MSN) encapsulated with sodium benzoate(SB) corrosion inhibitors were strategically incorporated in the MAO micropores and in the top EP layer. The influence of the strategic positioning of the nanocontainers on the corrosion protective performance of coating was investigated. The experimental results and analysis indicated that the superior corrosion resistance of the hybrid coating is ascribed to the protection mechanisms of the nanocontainers. This involves two phenomena:(1) the presence of the nanocontainers in the MAO micropores decreased the distance between MSN@SB and the substrate, demonstrating a low admittance value(^5.18 × 10^(-8)Ω^(-1)), and thus exhibiting significant corrosion inhibition and self-healing function;and(2) the addition of nanocontainers in the top EP layer densified the coating via sealing of the inherent defects, and hence the coating maintained higher resistance even after 90 days of immersion(1.13 × 10^(10)Ω cm^(2)).However, the possibility of corrosion inhibitors located away from the substrate transport to the substrate is reduced, reducing its effective utilization rate. This work demonstrates the importance of the positioning of nanocontainers in the coating for enhanced corrosion resistance,and thereby providing a novel perspective for the design of smart protective coatings through regulating the distribution of nanocontainers in the coatings.

关键词： Nanocontainers Self-healing coating Micro-arc oxidation Corrosion protection Magnesium alloys

Induction of immune tolerance with heart-thymus composite allotransplantation in rats

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Journal of Central South University of Technology 2005年第Z1期12卷 331-336页

作者： XIONG Hai-bo XIA sui-sheng WEN Hao HUANG Zu-fa YE Qi-fa Medical Academy of Transplantation the Third Xiangya Hospital Central South University Changsha 410013 China Institute of Transplantation Tongji Hospital Huazhong Science and Technological University Wuhan 430030 China Department of General Surgery the First Affiliated Hospital Xinjiang Medical University Urumqi 830054 China Medical Academy of Transplantation the Third Xiangya Hospital Central South University Changsha 410013 China Medical Academy of Transplantation the Third Xiangya Hospital Central South University Changsha 410013 China

Objective To study on the role of thymus transplantation for heart allograft in rats. Methods Vascularized heart-thymus combined transplantation was performed with microsurgical technique. Graft survival, histopathology, level of IL-2, IL-4 and its mRNA expression in serum and cardiac grafts were investigated. Results Heart-thymus combined transplantation achieved effect in the prolongation of cardiac graft survival with short-term administration of cyclosporine. Conclusions Vascularized thymus transplantation induced immune tolerance in thymectomized rats.

关键词： thymus transplantation immune tolerance rejection rat

T2 Mapping and Fat Quantification of Thigh Muscles in Children with Duchenne Muscular Dystrophy

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Current Medical Science 2019年第1期39卷 138-145页

作者： Liang YIN Zhi-ying XIE Hai-yan XU sui-sheng ZHENG Zhao-xia WANG Jiang-xi XIAO Yun YUAN Department of Radiology Peking University First HospitalBeijing 100034China Department of Neurology Peking University First HospitalBeijing 100034China Department of Radiology Second Affiliated Hospital of Anhui Medical UniversityHefei 230601China

Quantitative magnetic resonance image(MRI)in individual muscles may be useful for monitoring disease progression in Duchenne muscular dystrophy(DMD).The purpose of this study w批to measure丁2 relaxation time of thigh muscles in children with DMD and healthy boys,and to correlate the T2 relaxation time of muscles with the fat fraction(FF)at quantitative magnetic resonance and results of clinical ***-two boys with DMD and 18 healthy boys were evaluated with T2 mapping and three-point Dixon ***,body mass index(BMI),muscle strength assessment,timed functional tests(time to walk or run 10 metres,rise from the floor and ascend four stairs),and the North Star Ambulatory Assessment(NSAA)were ***’s correlation was used to assess the relationships between FF and clinical assessments and T2 relaxation *** mean T2 relaxation time of thigh muscles in DMD was significantly longer than that in the control group(P<0.05),except for the gracilis(P=0.952).The gracilis,sartorius and adductor longus were relatively spared by fatty infiltration in DMD *** T2 relaxation time was correlated significantly with the mean FF in all ***,BMI,total muscle strength score,timed functional tests and NSAA were significantly correlated with the overall mean T2 relaxation time.T2 mapping may prove clinically useful in monitoring muscle changes as a result of the disease process and in predicting the outcome of DMD patients.

关键词： T2 mapping Duchenne muscular dystrophy skeletal muscle fat infiltration

Establishment and improvement of model of vascularized heart-thymus composite transplantation in rats

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Journal of Central South University of Technology 2005年第z1期12卷 347-349页

Objective To establish and improve the model of heart-thymus composite *** Vascularized both lobes of the thymus is transplanted heterotopically with the heart as a composite graft in *** technique was developed and assessed,and viability of the grafts was evaluated *** Donor operation costed 38.5±3.52 min,vascular anastomosis costed 25.0±3.28 min,operating successful rate was 90%,acute rejection was observed in SD-Wistar group,viable thymus with normal microarchitecture was maintained in Wistar-Wistar *** The improved novel technique for combined heart-thymus transplantation is a valuable method for study of the role of thymus in transplantation immunity.

关键词： heart thymus composite transplantation rat animal model transplantation immunity