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介孔碳载体缓解碱性聚电解质燃料电池阳极水淹

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Chinese Journal of Catalysis 2024年第2期57卷 51-58页

作者：江文涌葛创新王功伟陆君涛肖丽庄林武汉大学化学与分子科学学院化学电源材料与技术湖北省重点实验室湖北武汉430072 武汉大学索维奇分子科学中心湖北武汉430072 武汉大学高等研究院湖北武汉430072

碱性聚电解质燃料电池(APEFCs)相较于目前研究最多的质子交换膜燃料电池(PEMFCs),其优势体现在阴/阳两极均可使用价格低廉的非贵金属催化剂,有望降低燃料电池的使用成本.APEFCs的研究在过去20年飞速发展,主要集中在高效碱性聚电解质(APE... 详细信息

碱性聚电解质燃料电池(APEFCs)相较于目前研究最多的质子交换膜燃料电池(PEMFCs),其优势体现在阴/阳两极均可使用价格低廉的非贵金属催化剂,有望降低燃料电池的使用成本.APEFCs的研究在过去20年飞速发展,主要集中在高效碱性聚电解质(APE)隔膜和阴/阳极催化剂等关键材料的研发.目前,APEFCs的性能已接近于PEMFCs,针对其研究也逐渐从关键材料的研发扩展到电池的稳定性和水管理等更深层次问题.相较于PEMFCs,APEFCs的水管理问题更为复杂.每当阳极产生4个水分子,阴极会消耗2个水分子,容易导致阴极缺水和阳极水淹,进而影响电池的性能和稳定性.对APEFCs水管理的优化将是实现电池性能和稳定性突破的重要方向.本文主要研究碳载体对APEFCs水管理的影响,合成了一系列介孔碳负载的Ru催化剂(Ru/MCP-x,x为MCP的孔径,x=30,50,100 nm),并以Ru/XC72催化剂为对照.扫描电镜和N2吸附-脱附结果表明,介孔碳载体具有三维贯通的孔结构,而XC72为实心碳颗粒.溶液电化学测试结果表明,不同催化剂在0.1 mol/L的KOH溶液中的氢氧化反应(HOR)活性相当.以Ru/MCP-x和Ru/XC72为阳极催化剂进行电池装配(记为Ru/MCP-x电池和Ru/XC72电池),结果表明,当使用高进气流量(1000 mL/min)时,Ru/MCP-x电池和Ru/XC72电池性能接近;当使用更接近实际工况的低进气流量(200 mL/min)时,所有电池性能均有所下降,且降幅存在明显差距.其中,Ru/MCP-50电池和Ru/MCP-100电池的降幅分别为36%和35%,而Ru/MCP-30电池和Ru/XC72电池的降幅分别为43%和72%.通过在低进气流量下改变进气湿度,结果发现,Ru/MCP-30电池和Ru/XC72电池性能大幅下降的原因是阳极发生水淹.弛豫时间分布(DRT)方法可以将不同弛豫时间的极化过程在时域中分离开来,从而可以分辨各极化过程对电池性能的影响.利用电化学交流阻抗(EIS)技术结合DRT方法进一步分析各电池在不同电流密度下的阻抗行为,DRT结果表明,在低进气流量下Ru/XC72电池的传质极化电阻显著高于Ru/MCP-x电池,说明阳极水淹导致了Ru/XC72电池的气体传质受阻,因而电池性能大幅下降.当MCP孔径增加至50和100 nm时,传质极化电阻在不同电流密度下始终处于较低水平,电池未发生明显水淹.这说明孔径的增加有效地缓解了低进气流量下阳极的水淹问题,从而保持较高的电池性能.综上,本文利用EIS-DRT方法比较了不同阳极碳载体对APEFCs性能和气体传质极化电阻的影响,表明介孔碳载体有利于缓解APEFCs中的阳极水淹问题,具有作为阳极载体的潜力.

关键词：钌介孔碳碱性聚电解质燃料电池水淹弛豫时间分布

The Role of Hydroxide Binding Energy in Alkaline Hydrogen Oxidation Reaction Kinetics on RuCr Nanosheet

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Chinese Journal of Chemistry 2022年第21期40卷 2495-2501页

作者： Chaoyi Yang Yunbo Li Chuangxin Ge wenyong jiang Gongzhen Cheng Lin Zhuang Wei Luo College of Chemistry and Molecular Sciences Wuhan UniversityWuhanHubei 430072China Hubei Key Labon Organic and Polymeric Opto-Electronic Materials Wuhan UniversityWuhanHubei 430072China

Unveiling the role of adsorbed hydroxide involved in the hydrogen oxidation reaction(HOR)under alkaline electrolyte is crucial for the development of advanced HOR electrocatalysts for the alkaline polymer electrolyte fuel cells(APEFCs).Herein,we report the synthesis of amorphous RuCr nanosheets with different molar ratios and their HOR performances under alkaline *** find a volcano correlation between the Cr content in RuCr nanosheets and their alkaline HOR *** results and density functional theory(DFT)calculation reveals that the optimized Cr content in RuCr nanosheets could lead to the optimum hydroxide binding energy(OHBE),contributes to their remarkable alkaline HOR performance with mass activity of 568.1 A·gPGM^(–1) at 50 mV,13-fold higher than that of Ru *** RuCr nanosheet is further used as the anodic electrocatalyst,a peak power density of 1.04 W·cm^(–2 )can be achieved in an APEFC.

关键词： Fuel cells Hydrogen oxidation reaction Hydroxide binding energy Electrochemistry Ruthenium

Microstructure in the Semi-solid State and Mechanical Properties of AZ80 Magnesium Alloy Reheated from the As-cast and Extruded States

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Acta Metallurgica Sinica(English Letters) 2013年第4期26卷 473-482页

作者： wenyong jiang Tian CHEN Liping WANG Yicheng FENG Yan ZHU Kaifeng WANG Jiapeng LUO Shouwei ZHANG College of Materials Science and Engineering Harbin University of Science and Technology

The multi-axial forging （MAF） process was introduced into the strain induced metal activation （SIMA） process to replace conventional forging. Microstructure evolution of MAF formed AZ80 magnesium alloy during partial remelting was investigated. Furthermore, the tensile mechanical properties for AZ80 magnesium alloy thixoextruded from the starting materials treated by MAF were determined. For comparison, as-cast AZ80 magnesium alloy was also thixoextruded. The results show that the SIMA route produced ideal, fine semi-solid microstructure, in which almost completely spheroidal primary solid grains had a little amount of entrapped liquid. The microstructure of the as-cast alloy in the semi-solid state is less spheroidized compared with the MAF alloy under the similar isothermal holding conditions. With prolonged holding time, the size of the solid grain increases and the degree of spheroidization is improved in the MAF formed alloys. However, the solid grain size of the as-cast alloys decreases initially, and then increases with further increasing temperature. The tensile mechanical properties for AZ80 magnesium alloy thixoextruded from the starting material produced by MAF are better than those of AZ80 magnesium alloy thixoextruded from the starting material produced by casting. The ultimate tensile strength, yield strength and elongation of the alloy thixoextruded from the starting material produced by MAF are 314 MPa, 238 MPa and 14%, respectively.

关键词： Magnesium alloy Microstructure Mechanical properties Partial remelting

Physical modeling of spent-nuclearfuel container

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China Foundry 2012年第4期9卷 366-369页

作者： Wang Liping Guo Erjun jiang wenyong Xue Muyu Liu Dongrong Ren Shanzhi School of Materials Science and Engineering Harbin University of Science and TechnologyHarbin 150040China School of Materials Science and Engineering Harbin Institute of TechnologyHarbin 150001China

A new physical simulation model was developed to simulate the casting process of the ductile iron heavy section spent-nuclear-fuel *** this physical simulation model,a heating unit with DR24 Fe-Cr-Al heating wires was used to compensate the heat loss across the non-natural surfaces of the sample,and a precise and reliable casting temperature controlling/monitoring system was employed to ensure the thermal behavior of the simulated casting to be similar to the actual ***,a mould system was designed,in which changeable mould materials can be used for both the outside and inside moulds for different *** casting test was carried out with the designed mould and the cooling curves of central and edge points at different isothermal planes of the casting were *** show that for most isothermal planes,the temperature control system can keep the temperature differences within 6 ℃ between the edge points and the corresponding center points,indicating that this new physical simulation model has high simulation accuracy,and the mould developed can be used for optimization of casting parameters of spent-nuclear-fuel container,such as composition of ductile iron,the pouring temperature,the selection of mould material and design of cooling *** addition,to maintain the spheroidalization of the ductile iron,the force-chilling should be used for the current physical simulation to ensure the solidification of casting in less than 2 h.

关键词：计算机仿真计算机模拟铸造铸造工艺

Efect of residual Al content on microstructure and mechanical properties of Grade B+Steel for castings for locomotives

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China Foundry 2013年第6期10卷 391-395页

作者： Wang Kaifeng Guo Erjun Cao Guojian Wang Liping Feng Yicheng jiang wenyong Tao Chunguo College of Materials Science and Engineering Harbin University of Science and Technology Qiqihar Railway Rolling Stock (Group) Co. Ltd.

The bogie made of Grade B+ steel is one of the most important parts of heavy haul trains. Some accidents were found to be the result of fracture failure of the bogies. It is very important to find the reason why the fracture failure occurred. Because Al was added for the final deoxidation during the smelting process of the Grade B+Steel, residual Al existed to some extent in the castings. High residual Al content in the bogie casting was presumed to be the reason for the fracture. In this work, the influence of residual Al content in the range of 0.015wt.% to 0.3wt.% on the microstructure and mechanical properties of the Grade B+ Steel was studied. The experimental results showed that when the residual Al content is between 0.02wt.% and 0.20wt.%, the mechanical properties of the steel meet the requirements of technical specification for heavy haul train parts, and the fracture is typical plastic fractures. If the residual Al content is less than 0.02wt.%, the microstructures are coarse, and the mechanical properties can not meet the demand of bogie steel castings. When the residual Al content is more than 0.2wt.%, the elongation, reduction of area, and low-temperature impact energy markedly deteriorate. The fracture mode then changes from plastic fracture to cleavage brittle fracture. Therefore, the amount of Al addition for the final deoxidation during the smelting process must be strictly controlled. The optimum addition amount needs to be controlled within the range of 0.02wt.% to 0.20wt.% for the Grade B+Steel.

关键词： bogie Grade B+Steel Al content mechanical properties

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弛豫时间分布方法的原理与应用

科学通报 2023年第30期68卷 3899-3912页

作者：江文涌杨铠聪王功伟陆君涛肖丽庄林武汉大学化学与分子科学学院化学电源湖北省重点实验室武汉430072

电化学阻抗谱(EIS)作为一种常用的电化学分析方法,被广泛应用于各类电化学体系.EIS数据的解释通常依靠等效电路模型方法,但该方法存在着不唯一性、电路参数过多及初始值选择困难等问题.弛豫时间分布(DRT)方法的出现较好地解决了等效电... 详细信息

电化学阻抗谱(EIS)作为一种常用的电化学分析方法,被广泛应用于各类电化学体系.EIS数据的解释通常依靠等效电路模型方法,但该方法存在着不唯一性、电路参数过多及初始值选择困难等问题.弛豫时间分布(DRT)方法的出现较好地解决了等效电路模型方法存在的问题.该方法能够将频率域中难以区分的极化过程在时间域中区分开来,而且无需对电化学体系建模,也不需要任何先验假设.目前,DRT方法已广泛应用于燃料电池、二次电池和电解器等各类电化学体系中.本文首先介绍DRT方法的理论;随后主要回顾其在实际电化学体系中对于极化过程的分离、归属、等效电路的预识别及二次检验等方面的应用,同时介绍了该方法的诸多拓展;最后,对DRT方法进行了总结与展望.相信随着阻抗数据测量精度与稳定性的提升以及DRT函数算法的发展,DRT方法将为电化学体系分析提供更加深入的信息.

关键词：电化学阻抗谱弛豫时间分布不适定问题正则化扩散时间分布微分电容分布

硅含量对耐热球墨铸铁显微组织和力学性能的影响

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金属热处理 2022年第9期47卷 227-233页

作者：赵竞王丽萍冯义成姜文勇王雷郭二军哈尔滨理工大学材料科学与化学工程学院黑龙江哈尔滨150040

采用光学显微镜、扫描电镜、电子万能拉伸试验机测试分析手段,研究硅含量对耐热球墨铸铁显微组织和室温、高温力学性能的影响规律。试验结果表明,随着硅含量的增加,石墨圆整度逐渐下降,硅含量(质量分数,下同)达到3.8%时,基体中开始出现... 详细信息

采用光学显微镜、扫描电镜、电子万能拉伸试验机测试分析手段,研究硅含量对耐热球墨铸铁显微组织和室温、高温力学性能的影响规律。试验结果表明,随着硅含量的增加,石墨圆整度逐渐下降,硅含量(质量分数,下同)达到3.8%时,基体中开始出现碎块状石墨,球化级别为3级。随着硅含量从2.8%增加至4.8%,珠光体含量从51.06%减少至8.65%。随着硅含量的增加,室温抗拉强度先上升后下降,伸长率逐渐下降,当硅含量为3.8%时,抗拉强度为726 MPa,伸长率为1.6%。随着硅含量的增加,高温抗拉强度逐渐上升,伸长率逐渐下降,当硅含量为4.8%时,抗拉强度为532 MPa,伸长率为6%。室温拉伸断口出现大量的解理面和河流花样,表现形式为脆性断裂。高温拉伸断口出现韧窝和撕裂棱,拉伸断口表现形式为韧-脆混合型断裂。

关键词：耐热球墨铸铁显微组织室温性能高温性能断口形貌

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如何提高企业集团管理的整体协同效应

中共贵州省委党校学报 2005年第6期 45-46页

作者：蒋文用贵州成黔集团贵州贵阳550001

本文主要从股权管理、法人治理结构、母子公司体制、企业文化建设等方面对提高企业集团整体协同效应进行探索和研究。

关键词：协同效应集权与分权全面预算文化整合

铜电解阴极钛板碳化硅悬浮液超声波协同清洗研究

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制造技术与机床 2024年第3期 140-146页

作者：蒋培民吴张永朱启晨蒋佳骏杨文勇张刚昆明理工大学机电工程学院云南昆明650500

铜电解阴极钛板作为铜电解工艺的重要组成部分,其表面质量对电解质量和效率及钛板本身使用寿命有显著影响。针对此问题,采用碳化硅悬浮液超声波协同清洗技术对钛板进行简单、高效、环保的表面处理。通过铝箔腐蚀法探究了最佳清洗参数,... 详细信息

铜电解阴极钛板作为铜电解工艺的重要组成部分,其表面质量对电解质量和效率及钛板本身使用寿命有显著影响。针对此问题,采用碳化硅悬浮液超声波协同清洗技术对钛板进行简单、高效、环保的表面处理。通过铝箔腐蚀法探究了最佳清洗参数,分析了清洗过程中的协同效应及其作用机理。通过SEM+EDS和接触角测量仪对钛板表面清洁度、微观形貌和湿润性进行表征和评价。结果表明:距离换能器78 mm、碳化硅颗粒质量分数为0.05%,粒径为70 nm、p H值为中性、温度为55℃时清洗效果最佳;碳化硅悬浮液作为清洗介质,其协同效应可以明显提高清洗效率,改善钛板表面质量;清洗前后的对比表明,协同清洗能够有效地去除钛板表面的污染物,提高表面洁净度和湿润性,恢复钛板表面微观形貌及金属光泽。研究为优化钛板清洗工艺提供参考依据。

关键词：铜电解阴极钛板超声波清洗铝箔腐蚀法协同效应表面质量