A REVIEW OF INVESTIGATION ON PITTING CORROSION OF ALUMINUM ALLOY

综述近年来国内外有关Al合金点腐蚀的研究概况 .包括特征电位的研究、点腐蚀发生发展机理的研究和缓蚀剂缓蚀机理研究等 .侧重介绍近几年在Al合金点腐蚀研究中具有空间分辨度的原位研究技术 .Pitting corrosion of aluminum alloy is a complex but important problem.This paper provides a review of the recent investigation of pitting corrosion of aluminum alloy.Characteristic potentials,mechanisms of the pitting initiation,protective mechanisms of inhibitors are included in this paper.In addition,some in situ imaging electrochemical techniques are discussed.These in situ methods include electrochemical scanning tunneling microscopy (ECSTM),atomic force microscopy (AFM),scanning Kelvin probe force microscopy (SKPFM),scanning microelectrode technique (SMET) and some other techniques.国家自然科学基金资助项目 (No .5 98710 43

钯原子修饰的金纳米颗粒乙醇氧化电催化剂（英文）

钯催化剂对碱性溶液的乙醇电催化氧化反应表现较好的催化活性.本文通过简单的化学沉积法,将钯原子成功修饰到金纳米颗粒表面,制备的催化剂对乙醇电催化氧化反应表现出比钯更好的催化性能.研究发现,钯原子不均匀地覆盖在金核表面,部分金原子暴露在外层.制备的催化剂的峰电流密度是钯催化剂的4.6倍,起始电势低100 m V.该催化剂较好的催化性能可能归因于金核的电子效应和表面双功能电催化反应机制.support from Research Grant Council(No.26206115) of the Hong Kong Special Administrative Region;;Scientific Research Fund of Zhejiang Provincial Education Department(No.Y201840545

仪器分析实验课程对拔尖人才培养的探讨与思考

以"拔尖班"实验教学为例,阐述了仪器分析实验课程如何实行多元化教学。仪器分析实验利用网络教学平台,实现了师生跨时间、空间的交流,通过开展拓展性实验,强化了"拔尖班"学生的探究与创新性思维体验。同时对"拔尖班"人才培养中存在的一些问题进行了探讨。国家基础科学人才培养基金(J1310024)2016年福建省本科高校教育教学改革研究项目(生物工程专业实验精品资源共享课建设项目)2017年福建省本科高校教育教学改革研究项目(FBJG20170277

高致病性禽流感病毒血凝素蛋白广谱中和表位模拟肽的筛选与鉴定

以H5N1型禽流感病毒HA蛋白广谱中和单抗8H5为基础,利用噬菌体展示肽库技术及类病毒颗粒融合表达技术研究HA模拟表位。ELISA检测结果显示:筛选获得模拟HA表位的模拟肽123,进行类病毒颗粒融合蛋白表达后,仍具有与8H5单抗特异结合的能力。免疫荧光检测结果说明,类病毒颗粒免疫小鼠后产生了能与HA交叉反应的抗体。禽流感病毒HA模拟表位的研究与性质的分析及类病毒颗粒融合蛋白的表达与活性分析、免疫原性分析,都为研制禽流感通用表位疫苗奠定了基础

Theoretical Studies of Metal-N-C for Oxygen Reduction and Hydrogen Evolution Reactions in Acid and Alkaline Solutions

单原子催化剂（SAC）由于其低成本和在各种电催化反应中潜在的高催化活性而被认为是铂族金属的有前景的替代材料,但仍然缺乏对不同金属氮碳材料催化剂之间活性差异的原子机理的理解。在此,通过实验和理论研究相结合,研究了非贵金属氮碳材料（Me-N-C,Me = Fe和Co）作为模型催化剂,以探索在普遍的pH值下氧还原反应（ORR）和氢析出反应（HER）的催化活性以及相对应的反应机理。原子理论模拟表明,Fe-N-C具有比Co-N-C高的ORR活性,这是因为其速率决定步骤的反应势垒较低,而HER的活性趋势却相反。我们的模拟结果与实验观察结果一致。Single atom catalysts (SAC) have been regarded as the promising alternatives to platinum group metals due to their low costs and potentially high catalytic activities in various electrocatalytic reactions. The atomic mechanism understanding of activity discrepancy among different metal and nitrogen co-doped carbon-based catalysts is still lacking. Here, non-precious metal and nitrogen co-doped carbons (Me-N-C, Me = Fe and Co) as the model catalysts are investigated by combining experimental and theoretical studies to explore the catalytic activities and corresponding reaction mechanisms toward oxygen reduction reaction (ORR) and hydrogen evolution reaction (HER) at universal pHs. Atomic theoretical simulations suggest that Fe-N-C has higher ORR activity than Co-N-C due to its lower reaction barrier of the rate-determining step, while the activity trend is reversed for HER. Our simulation results are consistent with experimental observations.通讯作者:秦雪苹,邵敏华E-mail:[email protected];[email protected]:Xue-PingQin,Min-HuaShaoE-mail:[email protected];[email protected].化工与生物工程系,香港科技大学,香港 9990772.能源材料与电信研究中心,魁北克 加拿大1. Department of Chemical and Biological Engineering, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong 999077, China2. INRS-énergie, Matériaux et Télécommunications, 1650 Boulevard Lionel Boulet, Varennes, Québec, Canada J3X 1S

三峡成库后香溪河库湾底栖动物群落演变及库湾纵向分区格局动态

水库生态系统演替是水库生态学研究及水库管理过程中都比较关注的问题。三峡水库自2003年6月成库以来，有关水库生态系统演替的研究却鲜见报道。以三峡水库香溪河库湾底栖动物为研究对象，分析了自2003年8月-2010年7月3个不同蓄水阶段底栖动物群落的演变状况，并对库湾纵向分区格局的动态变化进行了探讨。结果表明，水库蓄水后，摇蚊科和颤蚓科成为第一批定殖者，并以摇蚊科为主；随后，颤蚓科中的霍甫水丝蚓逐渐成为优势类群；直到2004年4月仙女虫科的肥满仙女虫与霍甫水丝蚓共同主导群落。一期蓄水后约1a，底栖动物密度和物种数呈现出明显的增长趋势，空间上呈现出"中间高、两头低"的格局。库湾总体密度于2006年4月达到最高值，高达24146个/m 2 。二期蓄水导致底栖动物总密度显著降低，而三期蓄水后则变化相对较小。随着时间的增长，库湾底栖动物偶见种出现的频率逐渐降低，群落逐渐趋于稳定。基于TWINSPAN（two-way indicator species analysis）的分析，一期蓄水后期，香溪河库湾纵向上底栖动物群落结构呈现出稳定的分区格局，库湾中部区域呈现出相同的群落类型，无季节变化；而自二期蓄水开始，库湾纵向上大部分样点的群落类型发生改变，表明二期蓄水的干扰较强；之后呈现出季节性波动，此种格局与水位的季节波动相关联，表明三峡水库底栖动物逐渐适应水库周期性的调度，群落结构呈现稳定的季节性周期波动

基于非贵金属氧还原催化剂的质子交换膜燃料电池性能

质子交换膜燃料电池的成本和寿命问题是制约其商业化的主要瓶颈. 开发高效稳定的新型非铂氧还原催化剂是降低电池成本的重要途径. 过渡金属鄄氮鄄碳型非贵金属催化剂具有较高催化活性尧资源丰富尧价格低廉等优点, 被认为是未来最有希望替代铂的氧还原催化剂. 本综述从催化剂的设计构筑尧 催化层结构优化以及电池测试等方面, 对过渡金属鄄氮鄄碳型非贵金属催化剂的国内外最新研究进展进行了重点讨论, 并对未来其发展趋势提出展望. The commercialization of proton exchange membrane fuel cells (PEMFCs) is hindered by high cost and low durability of Pt based electrocatalysts. Developing efficient and durable non-precious metal catalysts is a promising approach to addressing these conundrums. Among them, transition metals dispersed in a nitrogen (N)-doped carbon support (M-N-C) show good oxygen reduction reaction activity. This article reviews recent progress in M-N-C catalysts development, focusing on the catalysts design, membrane electrode assembly fabrication, fuel cell performance, and durability testing. Template-assisted approach is an efficient way to synthesize M-N-C materials with homogeneously dispersed single atom active site and reduced metal particles, carbides formation. However, the issue related to low intensity of active sites should be addressed via strengthening metal-ligand interaction and using high surface area precursors. In general, the catalyst loading for the membrane electrode assembly (MEA) of non-precious catalyst is high (3 ~ 4 mg·cm-2) in order to obtain acceptable performance, which is also highly dependent on ink preparation and coating protocol, ionomer/catalyst ratio, etc. The highest power densities for Fe-N-C and Co-N-C are reported to be 1.18 and 0.87 W·cm-2 with O2 at the cathode, respectively. Despite the significant progress in non-precious metal catalysts development, the undesired durability (only a few hundreds of hours) is still far from the target of 5000 h by 2025. Thus, much more efforts should be spent on improving their durability

三峡水库香溪河库湾底泥中总氮、总磷含量的时空分布

2004年10月—2006年7月,对三峡水库香溪河库湾底泥中总氮(TN)、总磷(TP)含量的时空分布特征及其影响因素进行了分析.结果表明:香溪河库湾底泥中TN、TP含量均表现为"中间高,两头低"的空间分布规律,其中,TN含量最高值为1.08 mg.g-1,出现在库湾中部区域,最低值为0.89 mg.g-1,出现在河口附近区域;TP含量最高值为1.07 mg.g-1,最低值为0.80 mg.g-1,分别出现在库湾中部和库尾.TN含量按秋季、冬季、春季的顺序依次降低,从春季到夏季则大幅上升,夏季达最高值;T

Fabrication of Composite Scanning Micro pH Electrode and Its Application in Localized Corrosion

研制了一种新型的微米级复合型扫描叫探针.该探针具有体积小、响应速度快、稳定性好和制作方便等优点,能很好地满足微区 PH快速测定的要求 应用复合型扫描微pH电极技术研究了Al/Cu合金在0.01mol·L-1NaCl溶液中开路状态下局部腐蚀发生的早期过程.A novel composite scanning micro pH electrode was fabricated. The IrOx-pH electrode produced in a carbonate melt exhibited high stability, a fast potential response and ideal Nernstian response. The slope of the electrode at 15℃ was 56. 8 mV/pH, which was very close to the theoretical value. The 90% potential response time for a pH change from 1. 75 to 13. 90 was less than 0. 5 s. The composite scanning micro pH electrode is a promising apparatus for detecting the pH distribution on metal/solution interface. pH image on the surface of Al/Cu galvanic couple showed that both the anodic and cathodic areas could be sensed well. Localized corrosion took place on the interface of Al/Cu couple. The localized corrosion developed with time and pH value around the pitting decreased gradually.国家自然科学基金（59871043）资助项