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新型炭材料 2015年第5期30卷 385-390页

作者： Valeriy V.Bolotov Vasiliy e.kan egor V.Knyazev Peter M.Korusenko Sergey N.Nesov Yuriy A.Sten`kin Viktor A.Sachkov Irina V.Ponomareva Omsk Scientific Center of Siberian Branch Russian Academy of Sciences

采用拉曼光谱仪、透射电镜、俄歇能谱仪、X射线光电子能谱仪等研究在Si O2/Si基底上化学沉积的多壁碳纳米管(MWCNTs)经390℃的空气中热处理120 min前后与HCl溶液化学处理前后的结构变化情况。拉曼光谱集中测试低频(250-300 cm-1)带。结... 详细信息

采用拉曼光谱仪、透射电镜、俄歇能谱仪、X射线光电子能谱仪等研究在Si O2/Si基底上化学沉积的多壁碳纳米管(MWCNTs)经390℃的空气中热处理120 min前后与HCl溶液化学处理前后的结构变化情况。拉曼光谱集中测试低频(250-300 cm-1)带。结果表明,经热处理和化学处理后,在250-300 cm-1形成的拉曼带在峰位和半宽几乎没变。由透射电镜可知,小直径碳纳米管的内径值与拉曼光谱测试结果一致。这些结果表明,低频带产生于小直径碳纳米管的内壁中碳原子的径向呼吸振动。

关键词：碳纳米管径向振动模式拉曼化学气相沉积显微镜

Locally repairable codes from combinatorial designs

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Science China(Information Sciences) 2020年第2期63卷 174-188页

作者： Yu ZHANG Haibin kan Shanghai Key Laboratory of Intelligent Information Processing School of Computer ScienceFudan University Fudan-Zhongan Joint Laboratory of Blockchain and Information Security Shanghai Engineering Research Center of Blockchain Shanghai Institute for Advanced Communication and Data Science

Locally repairable codes（LRCs） were proposed to reduce the repair degree in distributed storage systems. In particular, LRCs with availability are highly desirable for distributed storage systems, since this kind of codes provide the mechanism of local repair for code symbols and parallel reading of hot *** this paper, we propose four types of（n, k, r, t）;LRCs from combinatorial designs. We introduce several constructions of LRCs with strict availability and some constructions of distance-optimal LRCs with information-symbol locality. Most of our constructions in this paper are over F;, i.e., they are suitable for implementation.

关键词： locally repairable codes erasure codes combinatorial designs distributed storage systems codes with availability

Applying the Theory of Numerical Radius of Operators to Obtain Multi-observable Quantum Uncertainty Relations

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Acta Mathematica Sinica,english Series 2022年第7期38卷 1241-1254页

作者： kan He Jin Chuan HOU College of Mathematics Taiyuan University of TechnologyTaiyuan 030024P.R.China College of Information and Computer Science Taiyuan University of TechnologyTaiyuan 030024P.R.China

Quantum uncertainty relations are mathematical inequalities that describe the lower bound of products of standard deviations of observables(i.e.,bounded or unbounded self-adjoint operators).By revealing a connection between standard deviations of quantum observables and numerical radius of operators,we establish a universal uncertainty relation for k observables,of which the formulation depends on the even or odd quality of *** universal uncertainty relation is tight at least for the cases k=2 and k=*** two observables,the uncertainty relation is a simpler reformulation of Schr?dinger’s uncertainty principle,which is also tighter than Heisenberg’s and Robertson’s uncertainty relations.

关键词： Numerical radius of operators quantum uncertainty principle quantum observables quantum deviations

A review of linear carbon chains

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Chinese Chemical Letters 2020年第7期31卷 1746-1756页

作者： kan Zhang Yifan Zhang Lei Shi Check for updates State Key Laboratory of Optoelectronic Materials and Technologies Nanotechnology Research CenterSchool of Materials Science and EngineeringSun Yat-sen UniversityGuangzhou 510275China

Linear carbon chains(LCCs)are a one-dimensional sp1-hybridized allo trope of ca *** are extre mely unstable:The longer the LCCs,the less stable the ***,it is a big challenge to synthesize long *** the research on the short LCCs,e.g.,polyynes,can be traced back to the 18th,LCCs are still not well-known compared to other allotropes of carbon,e.g.,fullerenes,carbon nanotubes and ***,introducing recent progress on LCCs is of great significance to draw more attention in the community of nanocarbons as well as nanomaterials in ***,various excellent properties have been ***,LCCs with different length in many kinds of forms have been successfully *** this review,we summarized recent studies of polyynic LCCs from both theoretical and experimental ***,perspectives are highlighted to point out the further investigations of the materials.

关键词： Linear carbon chains Polyyne Carbyne Carbon nanotubes electronic property

Stability and regeneration of metal catalytic sites with different sizes in Fenton-like system

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Chinese Chemical Letters 2023年第8期34卷 142-146页

作者： Yanan Shang Yujiao kan Xing Xu School of Safety and environmental engineering Shandong University of Science and TechnologyQingdao 266590China School of environmental Science and engineering Shandong UniversityQingdao 266237China

Metal-based catalysts with different site sizes(e.g.,metal nanoparticles(NPs)and single atom catalysts(SACs))demonstrated outstanding catalytic activities in versatile Fenton-like ***,the surface/structural instability is a critical issue,which will result in rapid passivation in Fenton-like reaction and fail in long-term *** catalytic stability of the catalysts with different metal sizes considering versatile peroxides(H_(2)O_(2),peroxymonosulfate(PMS),and peroxodisulfate(PDS))should be *** addition,strategies for catalyst regeneration and recyclability improvement are also important to realize the metal-based catalysts for practical *** this review,catalytic stability of catalysts with different metal sizes in the backgrounds of versatile peroxides and water matrixes in Fenton-like reactions were first *** of metal catalytic sites with different methods were also ***,major challenges and development of methods concerning the stability and regeneration of metal catalytic sites with different sizes were discussed to understand the future researches of metal catalytic sites in Fenton-like reactions.

关键词： Size effect Metal nanoparticles catalysts Single atom catalysts Fenton-like

Arithmetic progressions in self-similar sets

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Frontiers of Mathematics in China 2019年第5期14卷 957-966页

作者： Lifeng XI kan JIANG Qiyang PeI Department of Mathematics Ningbo UniversityNingbo 315211China

Given a sequence{bi}i=1^n and a ratio λ∈(0,1),let e=Ui=1^n(λe+bi)be a homogeneous self-similar *** this paper,we study the existence and maximal length of arithmetic progressions in *** main idea is from the multip... 详细信息

关键词： Self-similar sets arithmetic progression (AP) β-expansions

THe GeNeRALIZeD SMASH PRODUCT AND COPRODUCT

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Chinese Annals of Mathematics,Series B 2000年第3期21卷 381-388页

作者： kan HAIBIN(Department of Computer Science, Fudan University, Shanghai 200433, China.) e-mail: hbkan@*** Department of Computer Science Fudan University Shanghai 200433 China

The author discusses the braiding structures of the generalized smash product bialgebra and the cobraiding structures of the generalized smash coproduct bialgebra. It is pointed out that doublecrossed product determined by a cocycle is the generalized smash product and that doublecocrossed coproduct determined by a weak R-matrix is the generalized smash coproduct.

关键词： Generalized smash product Generalized coproduct Braiding structure Cobraiding structure

Developing silicon-based photocathodes for CO_(2) conversion

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Science China Chemistry 2024年第6期67卷 1904-1921页

作者： Weijie Zhuang Miao kan Tao Meng Jinlong Zhang Key Laboratory for Advanced Materials and Joint International Research Laboratory of Precision Chemistry and Molecular engineering Feringa Nobel Prize Scientist Joint Research CenterSchool of Chemistry and Molecular EngineeringEast China University of Science and TechnologyShanghai200237China Shanghai engineering Research Center for Multimedia environmental Catalysis and Resource Utilization East China University of Science and TechnologyShanghai200237China

Photoelectrochemical(PeC)conversion of CO_(2) presents a promising avenue for solar-driven chemical fuel production,with silicon emerging as a cost-effective and high-light-absorbing material pivotal to this *** at exploring opportunities for industrializing PeC CO_(2) reduction(PeC-CO_(2)R)by minimizing reaction energy consumption,enhancing reaction efficiency and selectivity,this review summarizes recent advancements in developing Si-based photocathodes for PeC-CO_(2)*** outlines the fundamental principles,advantages,and limitations of Si photocathodes with key performance *** on this understanding,the strategies to enhance the performance of the PeC-CO_(2)R system,including light absorption,charge separation,and catalytic reactions are categorized as the interfacial modification,active site decoration,and protective layer *** design ideas of this advantageous three-layer structure in promoting the efficiency,stability,and selectivity have been ***,this review scrutinizes the influence of the photocathodic chemical *** review consolidates the mechanism insights and notable breakthroughs of various fuel generation processes within Si-based PeC-CO_(2)R *** this wealth of information offers an up-to-date perspective on the dynamic developments in silicon-based PeC-CO_(2) conversion and underscores the promising pathways toward the sustainable fuel synthesis from pollutant CO_(2).

关键词： photoelectrochemistry solar fuels silicon photocathodes carbon dioxide reduction microenvironment

Towards energy efficient Shape Rolling:Roll Pass Optimal Design and Case Studies

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Chinese Journal of Mechanical engineering 2019年第3期32卷 78-88页

作者： kan Huang Bin Huang Lei Fu Kazem Abhary School of Civil engineering Changsha University of Science and TechnologyChangsha 410114China School of engineering University of South AustraliaAdelaideSouth Australia 5095Australia

Shape rolling is widely employed in the production of long workpieces with appropriate cross-section profiles for other industrial applications. In the development of shape rolling systems, roll pass design (RPD) plays an essential role on the quality control of products, service life of rolls, productivity of rolling systems, as well as energy consumption of rolling operations. This study attempts to establish a generic strategy based on hybrid modeling and an improved genetic algorithm, to support the optimizations of RPD and shape rolling operations at a systematic perspective. Objectives include improving the quality and efficiency of RPD, reducing energy consumption of shape rolling, as well as releasing the demands on costly trails and expert knowledge in RPD. Hybrid modeling based on cross-disciplinary knowledge is developed to overcome the limitations of isolated single-disciplinary models. And conventional genetic algorithm is improved for the implementation of optimal design. Targeting to integrate empirical data and published reliable solutions into optimizations, a parameters estimation method is proposed to transfer the initially misaligned models into a uniform pattern. A tool based on the Matlab platform is developed to demonstrate the optimal design operations, with case studies involved to validate the proposed methodology.

关键词： Roll pass optimal design Hybrid modelling Genetic algorithm Parameters estimation