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From Femtochemistry to 4D Microscopy

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Science China(Physics,Mechanics & Astronomy) 2010年第6期53卷 977-986页

作者： zhong dongping Departments of Physics,Chemistry,and Biochemistry,Programs of Biophysics,Chemical Physics,and Biochemistry,191 West Woodruff Avenue,The Ohio State University,Columbus,OH 43210,USA Departments of Physics Chemistry and Biochemistry Programs of Biophysics Chemical Physics and Biochemistry The Ohio State University Columbus USA

To celebrate the 10th anniversary of the Nobel Prize for Femtochemistry,the field is overviewed with several classic examples and the new extension to Femtobiology. The revolutionary breakthrough in 4D electron microscopy is briefly introduced here and a new age to structural dynamics is rising on the horizon,an exciting time and a great opportunity for China and for the world.

关键词： femtosecond dynamics molecular coherence structural dynamics and complexity

Dynamics and mechanism of UV-induced DNA damage repair

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Dynamics and mechanism of UV-induced DNA damage repair

第一届全国生物物理化学会议暨生物物理化学发展战略研讨会

作者： dongping zhong~* Departments of Physics,Chemistry and Biochemistry,Programs of Biophysics,Chemical Physics and Biochemistry,This Ohio State University,Columbus,USA 43210

＜正＞Photolyases use photon energy to split ultraviolet-induced cyclobutane pyrimidine dimers or （6-4） photoproducts in damaged DNA,a precursor of skin *** this enzyme has been discovered for about 50 years,the molecular mechanism has never been directly revealed. Here,we report the direct mapping of entire catalytic processes through femtosecond

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来源： cnki会议评论

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cnki会议

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PAN中空纤维超滤膜污染与膜阻力测定

科学技术与工程 2006年第14期6卷 2191-2193页

作者：马立艳钟冬平福建工程学院环境与设备工程系福州350007

对膜污染问题进行了研究,指出浓差极化、滤饼层形成和膜孔堵塞是造成膜污染的主要原因。同时测定了PAN膜阻力,试验结果表明,PAN膜超滤过程中主要阻力来源为膜孔吸附、凝胶层及浓差极化等引起的膜污染阻力,占总阻力的71.61%。膜自身阻力... 详细信息

对膜污染问题进行了研究,指出浓差极化、滤饼层形成和膜孔堵塞是造成膜污染的主要原因。同时测定了PAN膜阻力,试验结果表明,PAN膜超滤过程中主要阻力来源为膜孔吸附、凝胶层及浓差极化等引起的膜污染阻力,占总阻力的71.61%。膜自身阻力和不可逆阻力分别占总阻力的28.39%和11.76%,所占比例较小,有利于实际应用。

关键词：超滤膜污染膜阻力

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大型客机蒙皮生产线制造效率分析

教练机 2022年第1期 65-68页

作者：熊旭钟冬平唐姗文松涛航空工业洪都江西南昌330095

为满足大型客机蒙皮批量生产要求,提高生产效率,本文对大型客机蒙皮生产线制造效率进行分析,找出了影响大型客机蒙皮交付进度的关键因素,并提出了提升蒙皮制造效率的方法。

关键词：蒙皮生产效率镜像铣工序流转

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一种带加强筋槽超薄铝合金蒙皮成形工艺研究

教练机 2021年第4期 54-58页

作者：周军朱乐宗钟冬平徐晏清航空工业洪都江西南昌330096

某型号带加强筋槽超薄铝合金飞机蒙皮零件成形工艺复杂,成形过程中经常出现鼓动和翘曲变形。为解决此类问题,本文对带加强筋槽超薄铝合金蒙皮成形工艺进行研究,通过对比分析零件落压成形工艺和橡皮囊液压成形工艺方法、设计合理的模具... 详细信息

某型号带加强筋槽超薄铝合金飞机蒙皮零件成形工艺复杂,成形过程中经常出现鼓动和翘曲变形。为解决此类问题,本文对带加强筋槽超薄铝合金蒙皮成形工艺进行研究,通过对比分析零件落压成形工艺和橡皮囊液压成形工艺方法、设计合理的模具结构、选择合理的毛料状态及下料尺寸,确定了该零件最终的成形工艺。结果表明:超薄铝蒙皮合金采用"CZ"料、下料尺寸为1260mmX360mm,橡皮囊液压成形的工艺方法能保证零件成形质量,降低制造成本,缩短零件生产制造周期。本文的研究成果在超薄铝合金蒙皮成形的实际生产中获得了应用。

关键词：带加强筋槽超薄铝合金蒙皮 "CZ"料下料尺寸橡皮囊液压成形模具结构

Influence Mechanism of Sulfide Ions during Manganese Electrodeposition

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Journal of Wuhan University of Technology(Materials Science) 2019年第6期34卷 1451-1459页

作者： XUE Jianrong zhong Hong WANG Shuai LONG dongping College of Chemistry and Chemical Engineering Hunan University of Science and TechnologyXiangtan 411201China College of Chemistry and Chemical Engineering Hunan Provincial Key Laboratory of Efficient and Clean Utilization of Manganese ResourcesCentral South UniversityChangsha 410083China Intelligent Manufacturing Institute ofHNUST Hunan University of Science and TechnologyXiangtan 411201China

Influence mechanism of sulfide ions(S^2-) during manganese electrodeposition from sulphate electrolyte was investigated. Under the experimental conditions, S^2- ion concentration and electrolyte pH represented significant multiple effects on the cathode current efficiency. Scanning electron microscope(SEM) indicated that electrodeposition manganese layer(EML) became refinement as S^2- ion concentration was increased. X-ray Diffraction(XRD) displayed that S^2- ion had negligible influence on the preferred orientation of the crystalline layer of the EML. S^2- ion had no influence on the chemical composition of EML. S^2- ion could improve the corrosion resistance of EML. The interaction mechanism of S^2- ion with manganese electrodeposition was systematically explored by analysing E-pH diagram, cyclic voltammetry curve, cathode polarization curve and electrochemical impedance method.

关键词： S^2-ion Manganese electrodeposition E-pH diagram electrochemical behavior

Spatially-separated and photo-enhanced semiconductor corrosion processes for high-efficient and contamination-free electrochemical nanoimprint lithography

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Science China Chemistry 2022年第4期65卷 810-820页

作者： Hantao Xu Lianhuan Han Jian-Jia Su zhong-Qun Tian dongping Zhan Key Laboratory of Physical Chemistry of Solid Surfaces(PCOSS) Engineering Research Center of Electrochemical Technologies of Ministry of EducationDepartment of ChemistryCollege of Chemistry and Chemical EngineeringXiamen UniversityXiamen 361005China Department of Mechanical and Electrical Engineering School of Aerospace EngineeringXiamen UniversityXiamen 361005China

Free of any thermoplastic or photocuring resists, electrochemical nanoimprint lithography(ECNL) has emerged as an alternative nanoimprint way to fabricate three-dimensional micro/nano-structures(3D-MNSs) directly on a semiconductor wafer by a spatially-confined corrosion reaction induced by the metal/semiconductor contact potential. However, the consumption of electron acceptors in the ultrathin electrolyte between imprint mold and semiconductor wafer will slow down or even cease the corrosion rate. To solve this problem, we change the short-circuited corrosion cell into a spatially-separated primary cell: the imprint mold compacted gallium arsenide(GaAs) wafer in the anodic chamber while the platinum(Pt) plate connected to the imprint mold in the cathodic chamber. Thus, the GaAs corrosion rate will be stabilized in its limiting steady-state current density because of the abundant source of electron acceptors in the catholic chamber. The corrosion processes can be photo-enhanced by white-light illumination. Consequently, both the accuracy and the efficiency are promoted dramatically, which are demonstrated by the excellent performance of the fabricated binary optical elements. Moreover, the contamination problem caused by the electron acceptors is totally avoided. All the results prove that this novel ECNL mode is competitive and prospective in imprinting 3D-MNSs directly on semiconductor wafer.

关键词： nanoimprint lithography electrochemical microfabrication semiconductor corrosion semiconductor microdevices 3D functional micro/nano-structures

Nanofabrication of the gold scanning probe for the STM-SECM coupling system with nanoscale spatial resolution

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Science China Chemistry 2017年第5期60卷 649-655页

作者： Fang-Fang Wang Wei Wang Xi He Lianhuan Han Jian-Zhang Zhou zhong-Qun Tian Zhao-Wu Tian dongping Zhan State Key Laboratory of Physical Chemistry of Solid Surfaces College of Chemistry and Chemical EngineeringXiamen University Chemical Engineering and Environmental Engineering College of Chemistry Liaoning Shihua University

Scanning probe is the key issue for the electrochemical scanning probe techniques(EC-SPM) such as EC-scanning tunnel microscopy(STM), EC-atomic force microscopy(AFM) and scanning electrochemical microscopy(SECM), especially the insulative encapsulation of the nanoelectrode probe for both positioning and electrochemical feedbacks. To solve this problem,we develop a novel fabrication method of the gold nanoelectrodes: firstly, a micropipette with nanomter-sized orifice was prepared as the template by a laser puller; secondly, the inside wall of micropipette apex was blocked by compact and conic Au nano-piece through electroless plating; thirdly, the Au nano-piece was grown by bipolar electroplating and connected with a silver wire as a current collector. The fabricated Au nanoelectrode has very good voltammetric responses for the electrodic processes of both mass transfer and adsorption. The advantage lies in that it is well encapsulated by a thin glass sealing layer with a RG value lowered to 1.3, which makes it qualified in the SECM-STM coupling mode. On one hand, it can serve as STM tip for positioning which ensures the high spatial resolution; on the other hand, it is a high-quality nanoelectrode to explore the local chemical activity of the substrate. The nanofabrication method may promote the SPM techniques to obtain simultaneously the physical and chemical images with nanoscale spatial resolution, which opens a new approach to tip chemistry in electrochemical nanocatalysis and tip-enhanced spectroscopy.

关键词： scanning probe SECM bipolar nanoelectrode electrochemical imaging

Electrochemical hydrogen-storage capacity of graphene can achieve a carbon-hydrogen atomic ratio of 1:1

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Science China Chemistry 2022年第2期65卷 318-321页

作者： Quanfeng He Lanping Zeng Lianhuan Han Juan Peng Matthew M.Sartin Yuan-Zhi Tan dongping Zhan zhong-Qun Tian State Key Laboratory of Physical Chemistry of Solid Surfaces Fujian Science&Technology Innovation Laboratory for Energy Materials of ChinaEngineering Research Center of Electrochemical Technologies of Ministry of EducationGraphene Industry and Engineering Research InstituteDepartment of ChemistryCollege of Chemistry and Chemical EngineeringDepartment of Mechanical and Electrical EngineeringSchool of Aerospace EngineeringXiamen UniversityXiamen 361005China Department of Chemistry College of Chemistry and Chemical EngineeringNingxia UniversityYinchuan 750021China

As a promising hydrogen-storage material,graphene is expected to have a theoretical capacity of 7.7 wt%,which means a carbon-hydrogen atomic ratio of 1:***,it has not been demonstrated yet by experiment,and the aim of the *** of Energy is to achieve 5.5 wt%in *** designed a spatially-confined electrochemical system and found that the storage capacity of hydrogen adatoms on single layer graphene(SLG)is as high as 7.3 wt%,which indicates a carbon-hydrogen atomic ratio of 1:1 by considering the sp^(3) defects of ***,SLG was deposited on a large-area polycrystalline platinum(Pt)foil by chemical vapor deposition(CVD);then,a micropipette with reference electrode,counter electrode and electrolyte solution inside was impacted on the SLG/Pt foil(the working electrode)to construct the spatially-confined electrochemical *** SLG-uncovered Pt atoms act as the catalytic sites to convert protons(H^(+))to hydrogen adatoms(H_(ad)),which then spill over and are chemically adsorbed on SLG through surface diffusion during the cathodic *** the electrode processes are reversible,the H_(ad) amount can be measured by the anodic stripping *** is the first experimental evidence for the theoretically expected hydrogen-storage capacity on graphene at ambient environment,especially by using H+rather than hydrogen gas(H_(2))as the hydrogen source,which is of significance for the practical utilization of hydrogen energy.

关键词： graphene hydrogen storage surface electrochemistry adsorption desorption spillover surface diffusion