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dynamic evolution of nitrogen and oxygen dual-coordinated single atomic copper catalyst during partial oxidation of benzene to phenol

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Nano Research 2022年第4期15卷 3017-3025页

作者： Weiming Chen Hongqiang Jin Feng He Peixin Cui Changyan Cao Weiguo Song Beijing National Laboratory for Molecular Sciences CAS Research/Education Center for Excellence in Molecular SciencesLaboratory of Molecular Nanostructures and NanotechnologyInstitute of ChemistryChinese Academy of SciencesBeijing 100190China Beijing National Laboratory for Molecular Sciences CAS Research/Education Center for Excellence in Molecular SciencesLaboratory of Organic SolidsInstitute of ChemistryChinese Academy of SciencesBeijing 100190China School of Chemical Sciences University of Chinese Academy of SciencesBeijing 100049China Key Laboratory of Soil Environment and Pollution Remediation Institute of Soil ScienceChinese Academy of SciencesNanjing 210008China

Single atom catalysts(SACs)with metal_(1)-N_(x)sites have shown promising activity and selectivity in direct catalytic oxidation of benzene to phenol.The reaction pathway is considered to be involving two steps,including a H_(2)O_(2)molecule dissociated on the metal single site to form the(metal_(1)-N_(x))=O active site,and followed by the dissociation of another H_(2)O_(2)on the other side of metal atom to form O=(metal_(1)-N_(x))=O intermediate center,which is active for the adsorption of benzene molecule via the formation of a C-O bond to form phenol.In this manuscript,we report a Cu SAC with nitrogen and oxygen dual-coordination(Cu1-N3O1 moiety)that doesn’t need the first H_(2)O_(2)activation process,as verified by both experimental and density function theory(DFT)calculations results.Compared with the counterpart nitrogen-coordinated Cu SAC(denoted as Cu1/NC),Cu SAC with nitrogen and oxygen dual-coordination(denoted as Cu1/NOC)exhibits 2.5 times higher turnover frequency(TOF)and 1.6 times higher utilization efficiency of H_(2)O_(2).Particularly,the coordination number(CN)of Cu atom in Cu1/NOC maintains four even after H_(2)O_(2)treatment and reaction.Combining DFT calculations,the dynamic evolution of single atomic Cu with nitrogen and oxygen dualcoordination in hydroxylation of benzene is proposed.These findings provide an efficient route to improve the catalytic performance through regulating the coordination environments of SACs and demonstrate a new reaction mechanism in hydroxylation of benzene to phenol reaction.

关键词： single atom catalyst coordination dynamic evolution benzene oxidation phenol

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Regional difference and dynamic evolution of development quality of power industry in China

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Chinese Journal of Population,Resources and Environment 2023年第1期21卷 1-12页

作者： Sha Yu Yongjian Pu Lefeng Shi Hao Yu Yixiang Huang School of Economics and Business Administration Chongqing UniversityChongqing 400044China National Center for Applied Mathematics in Chongqing Chongqing Normal UniversityChongqing 401331China College of Economics and Management Northwest A&F UniversityYangling 712100China

To achieve the goals of carbon peaking and carbon neutrality and maintain high-quality economic growth,China is currently striving to improve the quality of development of its power sector.In this regard,revealing the regional differences and evolutionary trends in the development quality of China’power sector has a high value to inspire the next improvement direction toward how to integrate regional power recourses to an overall optimization level.Motived by this purpose,this paper uses the entropy method to evaluate the com‐prehensive and subsystem indices of the development quality of the power industry,and reveals their re‐gional differences and evolutionary trends with the help of the Dagum Gini coefficient and Kernel density es‐timation methods.The findings show that:There are obvious regional differences in the development quality of China’s power industry,and the differences are steadily declining in all regions except the West.Regional differences are mainly derived from inter-regional differences,with the largest inter-regional differences in the East-Northeast region.Intra-regional differences show a distribution pattern of East>West>North‐east>Center.

关键词： Development quality of power industry Regional difference The Dagum Gini dynamic evolution Kernel density

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dynamic investigation of oxygen defects on transition metal-based electrocatalysts:formation,characterization,and mechanism during alkaline oxygen evolution reaction

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Science China Chemistry 2023年第8期66卷 2221-2237页

作者： Rongrong Zhang Qilong Wu Peter Sherrell Daohao Li Keke Huang Jun Chen Xiangdong Yao State Key Laboratory of Inorganic Synthesis and Preparative Chemistry College of ChemistryJilin UniversityChangchun130012China Intelligent Polymer Research Institute and ARC Centre of Excellence for Electromaterials Science Australian Institute for Innovative MaterialsUniversity of WollongongWollongongNSW2500Australia School of Science STEM CollegeRMIT UniversityMelbourneVIC3001Australia State Key Laboratory of Bio-fibers and Eco-textiles College of Materials Science and EngineeringQingdao UniversityQingdao266071China College of Advanced Energy Shenzhen CampusSun Yat-Sen University(SYSU)Shenzhen518100China

Oxygen defects play a critical role in the electrocatalytic oxygen evolution reaction(OER).Therefore,in-depth understanding the structure-activity-mechanism relationship of these defects is the key to design efficient OER electrocatalysts.This relationship needs to be understood dynamically due to the potential for irreversible phase transitions during OER.Consequently,significant efforts have been devoted to study the dynamic evolution of oxygen defects to shed light on the OER mechanism.This review critically examines and analyzes the dynamic processes occurring at oxygen defect sites during OER,including defect formation and defect evolution mechanisms,along with the advanced characterization techniques needed to understand these processes.This review aims to provide a comprehensive understanding of high-efficiency electrocatalysts,with a particular emphasis on the importance of in situ monitoring the dynamic evolution of oxygen defects,providing a new perspective towards efficient OER electrocatalyst design.

关键词： oxygen evolution reaction oxygen defects dynamic evolution in situ characterization electrocatalysis

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Engineering and dynamics of heterogeneous catalysts via metal single atoms as promoters/precursors

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Science China Chemistry 2024年第8期67卷 2547-2565页

作者： Jiwei Li Junli Xu Jingyun Yang Zitao Duan Zhun Zhang Haifeng Xiong State Key Laboratory of Physical Chemistry of Solid Surfaces College of Chemistry and Chemical Engineering Xiamen University Innovation Laboratory for Sciences and Technologies of Energy Materials of Fujian Province

Metal single-atom catalysts(SACs) have emerged as a focal point of research, captivating the scientific community due to their distinctive electronic properties and unparalleled catalytic prowess in the realm of heterogeneous catalysis. However, their significance transcends their role as mere active sites. Recent investigations have illuminated the multifaceted capabilities of metal single atoms as catalyst promoters and precursors, paving the way for the engineering of highly efficient heterogeneous catalysts. Single-atom promoters not only enhance the stabilization of active metals and tailor the support material, but regulate the reactive interfacial structure, eventually tuning the catalytic performance. Furthermore, SACs were also used as catalyst precursors to design new catalyst active sites. During the pretreatment or catalytic reaction, the structure of the metal single sites is changed significantly and transformed into the new and more active state, which improve the adsorption and reactive ability of reactants or intermediates. In this critical review, we comment the recent development of metal SACs used as catalyst promoters/precursors in engineering heterogeneous catalysts, including thermal catalysis and electrocatalysis. Furthermore, the dynamic evolution of the SACs during the pretreatment or catalytic reaction is also discussed. Finally, we provide our insight to potentially guide the future development on this emerging field.

关键词： dynamic evolution single-atom catalysts single-atom precursor single-atom promoter

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Defect spinel oxides for electrocatalytic reduction reactions

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Nano Research 2024年第5期17卷 3547-3570页

作者： Zhijuan Liu Jinyu Guo Lu-yu Liu Fen Wang Zhijie Kong Yanyong Wang Henan Key Laboratory of Crystalline Molecular Functional Materials Henan International Joint Laboratory of Tumor Theranostical Cluster MaterialsKey Laboratory of Special Environmental Functional Materials(Zhengzhou University)Ministry of EducationGreen Catalysis Centerand College of ChemistryZhengzhou UniversityZhengzhou 450001China State Key Laboratory of Chem/Bio-sensing and Chemometrics College of Chemistry and Chemical EngineeringHunan UniversityChangsha 410082China

Electrocatalytic reduction reactions play a crucial role in electrochemical energy conversion and storage technology,which are emerging technologies to ameliorate environmental problems.Spinel oxides are widely explored in electrocatalytic oxidation reactions but have a poor intrinsic ability to reduction reactions,making their electrocatalytic ability less effective.To improve this,defect engineering is a valuable method for regulating the electronic structure and coordination environment.Herein,this manuscript discusses the use of defect spinel oxides in electrocatalytic reduction reactions,including the different types of defects,construction methods,and characterization techniques.It also outlines the various applications of defect spinel oxides in different electrocatalytic reduction reactions.Finally,it goes over the challenges and future outlooks for defect spinels.This review aims to thoroughly explain how defect spinels work in electrocatalytic reduction reactions and serve as a helpful guide for creating effective electrocatalysts.

关键词： defect spinel oxides electrochemical reduction reactions electrocatalytic mechanism dynamic evolution

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Uncovering the dynamic evolution of nucleotidebinding site-leucine-rich repeat(NBS-LRR) genes in Brassicaceae

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Journal of Integrative Plant Biology 2016年第2期58卷 165-177页

作者： Yan-Mei Zhang Zhu-Qing Shao Qiang Wang Yue-Yu Hang Jia-Yu Xue Bin Wang Jian-Qun Chen State Key Laboratory of Pharmaceutical Biotechnology Center of Plant Genetics and Molecular EvolutionSchool of Life SciencesNanjing University Institute of Botany Jiangsu Province and Chinese Academy of Sciences

Plant genomes harbor dozens to hundreds of nucleotide-binding site-leucine-rich repeat （NBS-LRR） genes; however, the long-term evolutionary history of these resistance genes has not been fully understood, This study focuses on five Brassicaceae genomes and the Carica papaya genome to explore changes in NBS-LRR genes that have taken place in this Rosid II lineage during the past 72 million years. Various numbers of NBS-LRR genes were identified from Arabidopsis lyrata （198）, A. thaliana （165）, Brassica rapa （204）, Capsella rubella （127）, Thellungiella salsuginea （88）, and C. papaya （51）. In each genome, the identified NBS-LRR genes were found to be unevenly distributed among chromosomes and most of them were clustered together. Phylogenetic analysis revealed that, before and after Brassicaceae speciation events, both toll/interleukin-1 receptor-NBS-LRR （TNL） genes and non-toll/interleukin-1 receptor-NBS-LRR （nTNL） genes exhibited a pattern of first expansion and then contraction, suggesting that both subclasses of NBS-LRR genes were responding to pathogen pressures synchronically. Further, by examining the gain/loss of TNL and nTNL genes at different evolutionary nodes, this study revealed that both events often occurred more drastically in TNL genes. Finally, the phylogeny of nTNL genes suggested that this NBS-LRR subclass is composed of two separate ancient gene types： RPW8-NBS-LRR and Coiled-coiI-N BS-LRR.

关键词： dynamic evolution nucleotide-binding site-leucine-rich repeat gene phylogenetic relationship plant disease resistance

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中国淡水养殖业绿色发展水平的动态演进及收敛性分析

农业经济研究

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农业经济研究 2024年第4期

作者：杨正勇彭乐威闫周府

加快水产养殖业绿色发展是推进生态文明建设和保障国家粮食安全的重要工作，现有研究对水产养殖业绿色发展特征缺乏全面认识。本文构建了“资源投入—经济增长—环境效应”为一体的绿色全要素生产率理论分析框架，采用超效率EBM模型和GM... 详细信息

加快水产养殖业绿色发展是推进生态文明建设和保障国家粮食安全的重要工作，现有研究对水产养殖业绿色发展特征缺乏全面认识。本文构建了“资源投入—经济增长—环境效应”为一体的绿色全要素生产率理论分析框架，采用超效率EBM模型和GML指数法对“十一五”时期以来中国及各省份淡水养殖业绿色全要素生产率进行测算，并分析其动态演进及收敛性特征。结果表明，“十一五”阶段以来中国淡水养殖业绿色全要素生产率年均增长1.7％，累计增长23.6％，呈现“小幅下降—小幅增长—显著增长”的阶段性特征，其增长动力主要源自绿色技术进步，绿色技术效率贡献有限；不同地区淡水养殖业绿色全要素生产率年均增长不均衡，呈现“西快、东平、中慢”的分布格局，超变密度是区域差异的主要来源，地区内差异的贡献次之，地区间差异的贡献最小；此外，全国及三大区域均存在明显的σ收敛、绝对β收敛和条件β收敛。研究认为，为促进中国淡水养殖业绿色发展，需在加快绿色技术创新的同时提升绿色技术效率，因地制宜制定相关政策，推动区域绿色协调发展。

关键词：淡水养殖业绿色发展绿色全要素生产率动态演进收敛性 GML指数 green development of freshwater aquaculture green total factor productivity dynamic evolution convergence GML index

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Quasinormal modes and late time tails of perturbation fields on a Schwarzschild-like black hole with a global monopole in the Einstein-bumblebee theory

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Science China(Physics,Mechanics & Astronomy) 2023年第10期66卷 33-43页

作者： Xiaolin Zhang Mengjie Wang Jiliang Jing School of Physics and Electronics Synergetic Innovation Center for Quantum Effects and Applicationsand Institute of Interdisciplinary StudiesHunan Normal UniversityChangsha 410081China

In this paper we complete a systematic study on quasinormal modes(QNMs) and late time tails for scalar,Dirac and Maxwell fields on a spherically symmetric Schwarzschild-like black hole with a global monopole in the Einstein-bumblebee theory.To look for QNMs,we solve the equations of motion for all perturbation fields considered herein numerically,by employing both the matrix and the WKB methods,and find good agreements for numeric data obtained by these two techniques in the regime when both are valid.The impact of the bumblebee parameter c,the monopole parameter η^(2),and the multipole number l on the fundamental quasinormal frequency are analyzed in detail.Our results are shown in terms of the quasinormal frequency measured by √1+c M ,where M is a black hole mass parameter.We observe,by increasing the parameter c(η^(2)) with fixed first few l,that the real part of QNMs increases for all spin fields;while the magnitude of the imaginary part decreases for scalar and Dirac fields but increases for Maxwell fields.By increasing the multipole numberlwith fixed other parameters,we disclose that the real part of QNMs for all spin fields increases while the magnitude of the imaginary part decreases for scalar and Dirac fields but increases for Maxwell fields.In the eikonal limit(l>>n),QNMs for all spin fields coincide with each other and the real part scale linearly with l.In particular,the asymptotic QNMs approach the corresponding results given by the first order WKB formula,and only the real part of QNMs is dependent on the bumblebee and monopole parameters.In addition,it is shown that the late time behavior is determined not only by the multipole number but also by the bumblebee and monopole parameters,and is distinct for bosonic and fermonic fields.Moreover,the presence of the bumblebee(monopole) field makes the spin fields decay faster.Our results indicate,both in the context of QNMs and late time tails,that the bumblebee field and the monopole field play the same role in determining the dynamic evolution of pertu

关键词： Einstein-bumblebee theory perturbation fields dynamic evolution

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Spatiotemporal evolution of ecosystem service value and topographic gradient effect in the Da-Xiao Liangshan Mountains in Sichuan Province,China

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Journal of Mountain Science 2023年第8期20卷 2344-2357页

作者： JIN Tao CHEN Yang SHU Bo GAO Min QIU Jian School of Architecture Southwest Jiaotong UniversityChengdu 611756China Leshan Municipal Bureau of Planning and Natural Resources Leshan 614000China School of Architecture and Civil Engineering Xihua UniversityChengdu 610039China

The Da-Xiao Liangshan mountains are critical ecological function areas and essential ecological barriers in the upper reaches of the Yangtze River in China.This study selected a total of six periods of land use land cover(LULC)data from 1995 to 2020,to estimate the ecosystem service value(ESV)and analyzed its spatiotemporal evolution and topographic gradient divergence.The results showed that:(1)The ESV increased by 1.1 billion yuan,with an increase rate of 1.47%from 1995 to 2020.Two time periods,2005–2010 and 2015–2020,showed more significant increases than other periods.(2)The elevation and slope of mountainous areas determine the type of land use and further influence the spatial pattern of ESV.(3)Although woodland and grassland are the main land use types of the study area(more than 90%),the hydrological regulation function of the water area partially compensated for the impact of the encroachment of the built-up area on the ESV of grassland.(4)The spatial distribution of ESVs showed an inverted V-shaped characteristic as the topographic gradient increased,with the dominant position being the 5th topographic gradient zone.Finally,this study provided relevant recommendations for ecosystem protection and optimization.The findings of this study clarified the influence of topographical factors on the spatial differentiation of ESV and provided novel insights into ecosystem protection.

关键词： Ecosystem service value(ESV) dynamic evolution Terrain gradient effect Spatial pattern Liangshan Yi region

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Half-plane diffraction of Gaussian beams carrying two vortices of equal charges

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Chinese Physics B 2011年第10期20卷 219-227页

作者：何德高曾辉吕百达 Key Laboratory of Computational Physics of Sichuan Province Yibin University Department of Physical Science and Electronic Engineering Yibin University Institute of Laser Physics and Chemistry Sichuan University

This paper derives explicit expressions for the propagation of Gaussian beams carrying two vortices of equal charges m = ±1diffracted at a half-plane screen, which enables the study of the dynamic evolution of vortices in the diffraction field. It shows that there may be no vortices, a pair or several pairs of vortices of opposite charges m -=±, -1 in the diffraction field. Pair creation, annihilation and motion of vortices may appear upon propagation. The off-axis distance additionally affects the evolutionary behaviour. In the process the total topological charge is equal to zero, which is unequal to that of the vortex beam at the source plane. A comparison with the free-space propagation of two vortices of equal charges and a further extension are made.

关键词： two vortices of equal charges diffraction at a half-plane screen dynamic evolution

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