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Search Results: 1 - 10 of 345601 matches for " 魏子栋<br>WANG Yao "
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过渡金属氧化物氧还原催化剂的研究进展
Recent Process in Transition-Metal-Oxide Based Catalysts for Oxygen Reduction Reaction

王尧,<br>WANG Yao, WEI Zi-dong
- , 2018, DOI: 10.13208/j.electrochem.180147
Abstract: 摘要 过渡金属氧化物(TMOs)是阴离子交换膜燃料电池最有前途的氧还原催化剂之一. 目前,TMOs的氧还原活性同铂基催化剂相比仍然有一定的差距,研究如何合成具有高催化活性的TMOs催化剂非常重要. 导电性和本征活性一直被认为是开发高性能TMOs催化剂的两个关键因素,本文着重总结与评述了近年来有关TMOs氧还原催化剂在导电性和本征活性方面的研究进展,尝试提出了未来提高TMOs氧还原催化活性的努力方向
通过载体提高燃料电池催化剂的稳定性
Enhancing Stability of PEM Fuel Cell Catalysts via Support Changing

谢小红,<br>XIE Xiao-hong, WEI Zi-dong
- , 2015, DOI: 10.13208/j.electrochem.141052
Abstract: 摘要 Pt/C是目前质子交换膜燃料电池使用最广泛的一种催化剂,制约其实际应用的关键技术之一是稳定性,增强燃料电池催化剂稳定性研究一直是该领域的热点. 本文结合作者课题组的研究工作,综述了通过改进载体材料来提高Pt基催化剂稳定性的一些方法,指出采用更稳定的载体材料以及发展与金属催化剂纳米颗粒有强相互作用的载体材料,是增强催化剂稳定性的努力方向
Progress of SinoProbe-Deep Exploration in China 2008—2012
我国深部探测技术与实验研究与国际同步

DONG Shu-wen,LI Ting-dong,GAO Rui,Lü Qing-tian,WEI Wen-bo,YANG Jing-sui,WANG Xue-qiu,CHEN Qun-ce,SHI Yao-lin,HUANG Da-nian,CHEN Xuan-hua,ZHOU Qi,<br>董树文,李廷,高锐,吕庆田,文博,杨经绥,王学求,陈群策,石耀霖,黄大年,陈宣华,周琦
地球学报 , 2013,
Abstract: 深部探测技术与实验研究专项(SinoProbe,2008—2012)是我国历史上实施的规模最大的地球深部探测计划。专项成功实现了技术创新与重大科学发现的并举,完成了6000km深地震反射剖面,使我国进入国际深部探测大国的行列。专项建立了全国大地电磁参数网和地球化学基准网,实施的6口科学钻探获得重要发现,实现矿集区立体探测,关键地区地应力监测、岩石圈动力学模拟、大陆地壳结构与演化研究取得长足进展,探测仪器装备研制取得重要突破。专项被认为是我国由地质大国向地质强国转变的标志性重大地学计划,在世界地球科学领域具有很强的影响力,具有经济社会意义巨大创新价值,在大科学计划组织实施方面做了有益的探索,为实施"地壳探测工程"重大科技专项奠定了坚实基础。专项被两院院士评为"2011年度中国十大科技进展新闻"。"深部探测技术与实验研究专项与国际同步",获得中国地质科学院2012年度十大科技进展的特别进展。
磷化过程的Taguchi设计

电化学 , 1996,
Abstract: 通过对磷化液配方及磷化工艺的改进,解决了磷化液沉淀多,不稳定及磷化膜微观结构差的问题.针对钢铁磷化过程中出现的磷化膜质量与磷化面积之间的非线性关系,应用Taguchi方法,对磷化过程进行了优化,实现了磷化膜质量与磷化件面积之间的线性关系,磷化液连续循环使用的性能也得到根本的改进
“中庸”与“催化”随想
Rambling between “Zhong Yong” and “Catalysis”


- , 2016, DOI: 10.13208/j.electrochem.151144
Abstract: 摘要 “中庸”是传统的中国智慧,由孔子提出,不断被他的追随者丰富. “中庸”追求在各种矛盾中寻求平衡,并认为“过分”和“不及”都是不好的. 对于一个成功的催化剂,反应物的吸附,既不能太强,也不能太弱. 在这一点上,“催化”与“中庸”有极为相似之处. 本文以孔子与他的学生对话开始,先讲了3个 著名的“中庸”老故事,结合3个有“中庸”味道的“催化”案例,最后得出:好的“催化”,即是具有“中庸”味道的“催化”.
“Zhong Yong” represents a traditional Chinese wisdom, which was first proposed by Confucius and continuously richened by his followers. “Zhong Yong” pursues the balances among all kinds of contradictions, and insists that neither “too much” nor “not enough” is good. For a successful catalyst, on which the adsorption of reactants must be not so strong and not so weak either. On this point of view, there are the same pursuits for “Zhong Yong” and catalysis. In this paper, the author starts his story with a conversation between Confucius and his student, followed by 3 interesting stories happening in the ancient China, and then 3 examples in catalysis. In comparison with these stories and examples we can conclude that “Zhong Yong” and catalysis do share some common aesthetic standard. Doing catalysis with a taste of “Zhong Yong” must be very interesting and wonderful
《燃料电池电化学催化与催化剂》专辑序言 ——新能源产业的关键技术:燃料电池
Special issue: Electrocatalyst and Electrocatalysis in Fuel Cells Preface


- , 2016, DOI: 10.13208/j.electrochem.151140
Abstract: 摘要 随着世界石油储量的快速消耗以及由此带来的环境污染问题,世界各国都在积极寻找清洁无污染的可再生替代能源。以氢气的生产、储存、运输及利用为基础的“氢能经济”,对于摆脱人类对化石能源的依赖,实现可持续发展具有重要的意义。燃料电池作为将氢能直接转化为电能的洁净发电装置,是替代现有燃油发动机的最佳选择,不仅可以为现代交通工具提供理想的动力源,而且在移动通讯、潜艇、航空飞行器等方面也具有广阔的应用前景。
In the last two decades, fuel cells captured worldwide attention as a promising renewable emission-free technology to meet the increasing demand of clean energy for stationary and transportation applications. Currently, platinum (Pt) is the most widely used electrocatalyst for both hydrogen oxidation reaction (HOR) at anode and oxygen reduction reaction (ORR) at cathode. However, the high-cost and scarcity of Pt have become the major challenges for commercialization of fuel cells. To overcome the above mentioned problems, great progress has been made in developing more active electrocatalysts on the basis of Pt-based and Pt-free electro catalysts. For the Pt-based electrocatalysts, composition, morphology, surfaces tructure, synthesis method, and post-treatment play significant roles in determining their activity and stability. In general, theactivity of Pt-based electrocatalysts can be enhanced by alloying Pt with other transition metals, forming a core-shell structure to improve the utilization of Pt atoms, forming and maintaining structures with only the highest active facets exposed to electrolytes, and creating a porous structure toincrease the surface area and strain. For the Pt-free electrocatalysts, a great progress has been made in the last decade, including heteroatom-containing carbon, transition metal oxides and transition metal macrocyclic compounds. The best performing non-precious catalysts even exceed those Pt-based catalysts in alkaline electrolytes. Generally, their ORR activity is less competitive in acidic media. To review the achievements that have been madein China and push forward the further development of electrocatalyst and electrocatalysis in fuel cells, some leading scientists were invited to contribute their recent advances and prospects in this field. I wish to take this opportunity to thank all the authors, reviewers, and editorial staffs of Journal of Electrochemistry for their professional contributions to this special issue
Progress in Improving the Asymmetric Enantioselectivity of Lipase for Catalyzing Asymmetric Reaction
脂肪酶不对称立体选择性能改善的研究进展

NIE Yao,XU Yan,WANG Dong,<br>聂尧,徐岩,
过程工程学报 , 2002,
Abstract: Lipase has been extensively used in asymmetric reaction for producing optically pure compounds. Focused on improving the enantioselectivity of lipase for catalyzing asymmetric reaction, the recent researches have been summarized in this article, including reformation of lipase structure, reaction condition optimization, improvement of asymmetric reaction process and enantioselective inhibitation. Microwave irradiation can also be used to enhance the enantioselectivity of lipase in some level. Some traditional and new approaches, such as immobilization of enzyme, chemical modification, in vitro directed evolution, bio-imprinting, and optimization of reaction conditions were introduced.
电化学催化的密度泛函研究
李莉,
电化学 , 2014, DOI: 10.13208/j.electrochem.130893
Abstract: 围绕电化学催化问题,综述了密度泛函理论研究电极电势、电催化剂结构与物种的吸附脱附、电子转移以及电催化剂活性、稳定性的关系.电极电势与金属催化剂d带中心影响着电极表面物种的形成、吸附和脱附,通过催化剂合金化或表面修饰、载体-催化剂相互作用可实现催化剂d带中心的调控,寻找最优吸附强度的催化剂,以期提高催化活性;通过电极电势与催化剂的HOMO能级的调控,实现与电子受体物质LUMO能级的匹配,达到促进或抑制催化剂与电子受体物质之间电子转移的快慢.
非贵金属氧还原催化剂的研究进展
Recent Progress in Non-Precious Metal Catalysts for Oxygen Reduction Reaction

王俊,()
- , 2017, DOI: 10.3866/PKU.WHXB201702092
Abstract: 开发可替代铂的非贵金属催化剂是今后燃料电池催化剂的重要发展方向,本文结合课题组研究的工作,总结了近年来非贵金属在氧还原催化方面的研究进展。并着重从材料合成和机理两个方面分析了目前在开发过渡金属氧化物、含过渡金属的氮掺杂碳材料和杂原子掺碳材料中存在的问题,提出了这些非金属催化剂今后的研究重点和努力方向。Email: zdwei@cqu.edu.cn; Tel: +86-23-65105161
Non-precious metal catalysts should be studied to substitute precious Pt catalysts. Recent developments of non-precious-metal catalysts (combined with the achievements of our group) are summarized in this paper. The main issues that exist in the transition metal oxides, metal-nitrogen-carbon material, and heteroatom-doped carbon material are highlighted from the aspects of the synthetic methods and mechanisms. The research tendency and perspective of these non-precious metal catalysts are provided
层状软岩隧道围岩破坏的连续-离散耦合分析
Failure Analysis on Surrounding Rock of Soft-Layered Rock Tunnel Using Coupled Continuum-Discrete Model

徐国文, 何川, 汪耀,全<br>XU Guowen, HE Chuan, WANG Yao, CHEN Ziquan
- , 2018, DOI: 10.3969/j.issn.0258-2724.2018.05.013
Abstract: 为了研究层状岩体中隧道开挖后围岩的破坏机理,以汶马高速鹧鸪山隧道为例,基于离散元-有限差分耦合算法,建立了一种新的层状软岩隧道开挖模拟方法,采用该方法对不同地应力场、层理间距等因素影响下围岩的破坏模式进行了数值模拟.研究结果表明:隧道开挖后,应力重分布导致强度较低的层理面首先发生滑移及张开破坏,岩体的滑移及张开使得应力场受到进一步扰动,导致层间岩体产生拉裂破坏;同种水平应力条件下,随着侧压力系数的减小,岩体产生的微裂纹不断增多.当侧压力系数为1.00、0.80、0.67、0.57、0.50时,微裂纹总数分别为304、391、602、999、1 240;当层理间距为0.6 m时,层理对围岩破坏形态起控制作用;随着层理间距从0.6 m增加至1.2 m,层理对围岩破坏模式的控制作用减弱,围岩的破坏形态与均质围岩相似.
:In order to study the failure mechanism of layered surrounding rock after tunnel excavation,taking the Zhegu mountain tunnel of Wenma highway as an example,a new numerical approach is put forward based on continuum-discrete coupling method. The failure patterns of surrounding rock under different geo-stress fields and bedding spacing are obtained through this method. The results show thatslipping and opening failure occurs on joint surface because of its low strength after stress redistribution during tunnel excavation. Then,stress field is disturbed furtherly and this disturbance leads to tensile failure of rock matrix;Micro-cracks in rock mass increases with the decrease of lateral pressure coefficient for the same stress level. When the lateral pressure coefficient is 1.00,0.80,0.67,0.57,and 0.50,the total number of micro-cracks is 304,391,602,999,and 1240,respectively. When the bedding spacing is 0.6 m,bedding has a controlling influence on the failure mode of surrounding rock,while this influence is weakened and the failure mode is similar to that of homogeneous surrounding rock with the increase of bedding spacing from 0.6 m to 1.2 m
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