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The cycloaddition reaction of ethylene and methane mediated by Ir^(+) to generate a half-sandwich structure Ir HCp^(+)

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Chinese Chemical Letters 2023年第1期34卷 192-197页

作者： Wei Li Hechen Wu xunlei ding Xiaonan Wu School of Mathematics and Physics North China Electric Power UniversityBeijing 102206China Department of Chemistry Fudan UniversityShanghai 200433China Institute of Clusters and Low Dimensional Nanomaterials North China Electric Power UniversityBeijing 102206China

The cycloaddition reactions of methane and ethylene mediated by Ir^(+) have been designed and studied by the techniques of mass spectrometry in conjunction with theoretical *** have shown that Ir^(+) can mediate the cycloaddition reaction of CH4and two C_(2)H_(4) to generate a half-sandwich structure IrHCp^(+)(Cp=η^(5)-C_(5)H_(5))including pentamethylcyclopentadienyl ligand by continuous dehydrogenation reaction with the forming of three C-C bonds and seven C-H *** orbital analysis indicates the mechanism of the cyclization reaction to generation of pentamethylcyclopentadienyl ligand with odd number carbon atom depends on the overlap ofπorbitals in-C_(2)H_(2) and carbene,which is more difficult than the forming of cyclobutadiene ligand and *** study may help to understand the reaction mechanism in the cycloaddition reactions of organic compounds,which will be useful to guide the rational design of new catalysts with tailored selectivity and increased efficiency.

关键词： Cycloaddition reaction Mass spectrometry Theoretical calculation Half-sandwich structure

Theoretical study of partial oxidation of ethylene by vanadium trioxide cluster cation

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Chinese Science Bulletin 2009年第16期54卷 2814-2821页

作者： WANG ZheChen ding xunlei MA YanPing CAO Hai WU XiaoNan ZHAO YanXia HE ShengGui Beijing National Laboratory for Molecular Sciences (BNLMS) and State Key Laboratory for Structural Chemistry of Unstable and Stable Species Institute of Chemistry Chinese Academy of Sciences Beijing 100190 China Graduate University of Chinese Academy of Sciences Beijing 100039 China

Density functional theory (DFT) study of reaction between vanadium trioxide cluster cation (VO3+) and ethylene (C2H4) to yield VO2+ + CH3CHO (acetaldehyde) and VO2CH2+ + HCHO (formaldehyde) is carried out. Structures of all reactants, products, intermediates, and transition state in the reaction have been optimized and characterized. The results show unexpected barriers in the reaction due to the existence of a η2-O2 moiety in the ground state structure of VO3+. The initial reaction steps combining ethylene adsorption, C=C activation and O-O cleavage are proposed as rate limiting processes. Comparison of reactions of VO3+ + C2H4 with VO3 + C2H4 and VO2+ + C2H4 in the previous studies is made in detail. The results of this work may shed light on the understanding of C=C bond cleavage in related heterogeneous catalysis.

关键词：氧化乙烯氧化钒离子簇氧化反应密度泛函理论基团结构反应步骤速率限制

Geometric structures,electronic characteristics,stabilities,catalytic activities,and descriptors of graphene-based single-atom catalysts

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Nano Materials Science 2020年第2期2卷 120-131页

作者： Weijie Yang Shaopeng Xu Kai Ma Chongchong Wu Ian D.Gates xunlei ding Weihua Meng Zhengyang Gao School of Energy and Power Engineering North China Electric Power UniversityBaoding071003China Department of Chemical and Petroleum Engineering University of CalgaryT2N 1N4CalgaryAlbertaCanada School of Mathematics and Physics North China Electric Power UniversityBeijing102206China The Flame Retardant Material and Processing Technology Engineering Research Center of Hebei Province College of Chemistry and Environmental ScienceHebei UniversityBaoding071002China

Single-atom catalysts(SACs)have been a research hotspot due to their high catalytic activity,selectivity,and atomic utilization ***,the theoretical research of SACs is relatively fragmented,which restricts further understanding of SAC stability and *** address this issue,we report our analysis of the geometric structures,electronic characteristics,stabilities,catalytic activities,and descriptors of 132 graphene-based singleatom catalysts(M/GS)obtained from density functional theory *** on the calculated formation and binding energies,a stability map of M/GS was established to guide catalyst *** effects of metal atoms and support on the charge of metal atoms are *** catalytic activities of M/GS in both nitrogen and oxygen reduction reactions are predicted based on the calculated magnetic moment and the adsorption *** with the electronegativity and d-band center,a two-dimensional descriptor is proposed to predict the O adsorption energy on M/*** importantly,this theoretical study provides predictive guidance for the preparation and rational design of highly stable and active single-atom catalysts using nitrogen doping on graphene.

关键词： Single-atom catalyst Graphene Stability Activity Density functional theory Reaction descriptor

Oxygen Molecule Activation on Single-Atom Catalysts with Cu, Ag, and Au: A Cluster Model Study

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Journal of Materials Science and Chemical Engineering 2021年第4期9卷 46-59页

作者： Yangliu Wu xunlei ding Wei Li Joseph Israel Gurti School of Mathematics and Physics North China Electric Power University Beijing China Institute of Clusters and Low Dimensional Nanomaterials North China Electric Power University Beijing China

(M = Au, Ag, Cu;n= 1, 2, 3) clusters were used as a cluster model to study the activation of oxygen molecules on single-atom catalysts. Structures of clusters were studied by density functional calculations with global optimization. For each n, the most stable structures are quite similar for different metal types, and the oxygen molecule prefers to be adsorbed onto M atoms. It is found that the activation degree of oxygen is higher on clusters with non-noble metal Cu than that of Ag or Au containing clusters, by comparing the changes of O-O bond length and vibrational frequency, natural charge population analysis, Fuzzy bond order analysis, and energy barriers of O2 dissociation. CO oxidation was used as a probe reaction to study the reactivity of Cu-containing clusters, and it is found that the reactivity decreases with the increase of the size of silicon-oxygen clusters. Our results give a new aspect to understand the reaction mechanism of non-precious metal single-atom catalyst for oxygen activation with high efficiency.

关键词： Oxygen Activation Single-Atom Catalysis Non-Noble Metals Density Func-tion Theory Micro-Mechanism

CALCULATION OF NONLINEAR MAGNETIC FIELDS IN CYLINDRICALLY SYMMETRIC SYSTEM

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Journal of Electronics(China) 2003年第1期20卷 33-37页

作者： Wu xunlei Chen Xinqiao ding Yaogen (Institute of Electronics, Chinese Academy of Sciences, Beijing 100080) Institute of Electronics Chinese Academy of Sciences Beijing 100080

For the calculation of non-linear magnetic fields, a simple program can be as effective as a large commercialized software package. If relaxation methods are used, they must include successive over-relaxation and under-relaxation and much attention must be paid to the relaxation factor and the interpolation. In this paper some skills are proposed on the setting of an interpolation switch and the choosing of saturation point so as to assure satisfied convergence properties. The numerical results by using these methods conform well to the tests.

关键词： Saturation Convergence Interpolation

单个金或银原子掺杂的氧化钒团簇上的甲烷活化反应

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物理化学学报 2019年第9期35卷 1005-1013页

作者：王丹丁迅雷廖珩璐戴佳钰国防科技大学文理学院物理系长沙410073 华北电力大学数理学院北京102206

运用密度泛函理论系统研究了甲烷在MV3Oyq (M=Au/Ag,y=6–8,q=0或±1)团簇上的吸附和活化。研究得到了吸附体系的微观几何构型、吸附能、电荷分布等性质,找到了5个可以明显活化甲烷分子的含Au团簇。在这些体系中,Au均吸附在基底团簇V3Oy... 详细信息

运用密度泛函理论系统研究了甲烷在MV3Oyq (M=Au/Ag,y=6–8,q=0或±1)团簇上的吸附和活化。研究得到了吸附体系的微观几何构型、吸附能、电荷分布等性质,找到了5个可以明显活化甲烷分子的含Au团簇。在这些体系中,Au均吸附在基底团簇V3Oyq的O位置,而CH4均在Au原子上被活化。团簇电荷对活化能力有明显影响,阳离子团簇的活化能力最强,中性体系次之,阴离子团簇的活化能力很弱。测试计算表明引入D3色散矫正对于体系结构和能量的计算结果影响不大。本文作为单原子催化剂上甲烷吸附和活化反应的团簇模型研究,为进一步研究单原子催化剂上甲烷的活化机理提供了基础,也为合理设计低温下甲烷转化的单原子催化剂提供了有益的线索。

关键词：甲烷活化金属氧化物团簇贵金属单原子催化密度泛函理论

化学气相沉积法控制合成单层MoSe_2薄膜

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中国科技论文 2018年第18期13卷 2082-2086页

作者：王鑫王文杰邓加军叶晨骁王雅雅车剑韬丁迅雷华北电力大学数理学院北京102206

为了寻找最优化的实验条件得到大面积且高晶体质量的二维过渡金属硫族化合物(two-dimensional transition metal dichalcogenides,2DTMDCs)薄膜材料,选择用化学气相沉积(chemical vapor deposition,CVD)法,通过不断优化实验参量,制备出... 详细信息

为了寻找最优化的实验条件得到大面积且高晶体质量的二维过渡金属硫族化合物(two-dimensional transition metal dichalcogenides,2DTMDCs)薄膜材料,选择用化学气相沉积(chemical vapor deposition,CVD)法,通过不断优化实验参量,制备出了单层MoSe_2薄膜,并利用Raman光谱及光致发光光谱对样品的层数和带隙宽度进行表征。通过大量实验发现,在用CVD法制备单层MoSe_2薄膜时,实验的初始压强及衬底与前驱体的距离会影响样品的生长。于是通过对比实验,探究了起始压强及衬底与前驱体的距离对单层MoSe_2薄膜生长的影响。得到了最优化的压强及衬底与前驱体的距离。

关键词：凝聚态物理学二维材料单层MoSe2 化学气相沉积法生长参数

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水工金属结构T型焊缝焊接质量相控阵检测

大坝与安全 2020年第1期34卷 63-65,68页

作者：黄迅雷丁鹏马光飞关磊岳高峰林光辉水利部产品质量标准研究所浙江杭州310012 水利部杭州机械设计研究所浙江杭州310012

通过简单仿真试验介绍CIVA软件在水工金属结构安全评估中的作用,可以与试验结合,确认缺陷的危害性等。对T型工件进行相控阵检测,发现了工件中存在的4个缺陷,其中一个母材缺陷、一个小缺陷,对缺陷进行了定量分析,验证了相控阵检测在T型... 详细信息

通过简单仿真试验介绍CIVA软件在水工金属结构安全评估中的作用,可以与试验结合,确认缺陷的危害性等。对T型工件进行相控阵检测,发现了工件中存在的4个缺陷,其中一个母材缺陷、一个小缺陷,对缺陷进行了定量分析,验证了相控阵检测在T型焊缝等异形结构检测中的可靠性和高效性。

关键词：相控阵检测 T型焊缝角接接头水工金属结构

论“三段六步”实战教学法对法律实践思维的培养——以湖南快乐阳光有限公司诉迅雷公司不正当竞争案为例

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当代教育理论与实践 2018年第3期10卷 23-28页

作者：夏新华丁广宇湖南师范大学法学院湖南长沙410081

"三段六步"实战教学法是由湖南师范大学法学院与长沙市中级人民法院共同推动的创新法治人才培养机制的一种全新的实践教学方式。在该教学改革的第一次实践活动中,模拟原告方通过湖南快乐阳光有限公司诉迅雷公司不正当竞争一案,体会到在... 详细信息

"三段六步"实战教学法是由湖南师范大学法学院与长沙市中级人民法院共同推动的创新法治人才培养机制的一种全新的实践教学方式。在该教学改革的第一次实践活动中,模拟原告方通过湖南快乐阳光有限公司诉迅雷公司不正当竞争一案,体会到在分析法律事实、提炼法律关系上存在的不足,对本案涉及到的竞争关系进行了更深入的思考,从多个角度提升自己的法律实践思维能力,充分体现"三段六步"实战教学法"指导专业性、比对及时性、多元视角性、角色转换性"的特点,为卓越法律人才培养模式的创新做出了积极的贡献。

关键词：三段六步实战教学法法律实践思维不正当竞争人才培养