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Spacelike Framed Curves with lightlike Components and Singularities of Their Evolutes and Focal Surfaces in Minkowski 3-space

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Acta Mathematica Sinica,English Series 2024年第6期40卷 1521-1532页

作者： peng cheng li Dong He PEI Xin ZHAO School of Mathematics and Statistics Northeast Normal UniversityChangchun 130024P.R.China Department of Mathematics Harbin Institute of TechnologyWeihai 264209P.R.China School of Mathematics and Statistics Qingdao UniversityQingdao 266071P.R.China

In this paper,we define the evolute and focal surface of a spacelike framed curve with lightlike components in Minkowski *** is a generalization of the previous results of regular spacelike curves,since singularities are allowed in the original spacelike curves studied by spacelike framed curves with lightlike ***,we show a new geometric invariant to characterise singularities of the focal ***,the classification theorem and recognition theorem for the singularities of the focal surface in generic are also given.

关键词： Evolutes focal surfaces spacelike framed curves singularities

Multiphoton quantum dynamics of many-electron atomic and molecular systems in intense laser fields

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Chinese Physics B 2020年第8期29卷 115-126页

作者： peng-cheng li Shih-I Chu Research Center for Advanced Optics and Photoelectronics Department of PhysicsCollege of ScienceShantou UniversityShantou 515063China Key Laboratory of Intelligent Manufacturing Technology of MOE Shantou UniversityShantou 515063China Department of Chemistry University of KansasLawrenceKansas 66045USA

We present the recent new developments of time-dependent Schrödinger equation and time-dependent density-functional theory for accurate and efficient treatment of the electronic structure and time-dependent quantum dynamics of many-electron atomic and molecular systems in intense laser *** extend time-dependent generalized pseudospectral(TDGPS)numerical method developed for time-dependent wave equations in multielectron *** TDGPS method allows us to obtain highly accurate time-dependent wave functions with the use of only a modest number of spatial grid point for complex quantum dynamical *** usefulness of these procedures is illustrated by a few case studies of atomic and molecular processes of current interests in intense laser fields,including multiphoton ionization,above-threshold ionization,high-order harmonic generation,attosecond pulse generation,and quantum dynamical processes related to multielectron *** conclude this paper with some open questions and perspectives of multiphoton quantum dynamics of many-electron atomic and molecular systems in intense laser fields.

关键词： multiphoton ionization above-threshold ionization high-order harmonic generation attosecond pulse generation

Effect of Ni doping on the microstructure and magnetic properties of FePt films

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Rare Metals 2009年第3期28卷 257-260页

作者： DONG Kaifeng cheng Xiaomin YAN Junbing cheng Weiming li peng YANG Xiaofei Department of Electronic Science and Technology Huazhong University of Science and Technology Wuhan 430074 China

FePtNi films with different Ni contents were deposited on glass substrates by RF magnetron sputtering, and the L10-FePtNi films were obtained after the asdeposited samples were subjected to vacuum annealing. The magnetic properties, structures, and orientations of the L10-FePt films with Ni doping were studied. The results show that with increasing Ni content, the （001） peak position of the FePtNi films shifts to a higher angle in comparison with FePt, which suggests that there is partial Ni substitution in the L10 lattice. The perpendicular coercivity decreases from 661 to 142 kA/m and magnetization decreases from 512 to 433 kA/m with increasing Ni content. In comparison with FePt films, the FePtNi films can effectively reduce the Curie temperature, which makes FePtNi films promising media candidates in thermally assisted recording （TAR）.

关键词： FePtNi films Curie temperature magnetization coercivity

Recent Progress in Covalent Organic Frameworks(COFs) for Electrocatalysis

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Chinese Journal of Structural Chemistry 2022年第11期41卷 84-99页

作者： Cha li Zining Qiu Hongming Sun Yijie Yang cheng-peng li College of Chemistry Tianjin Key Laboratory of Structure and Performance for Functional MoleculesTianjin Normal UniversityTianjin 300387China

Electrocatalysis provides various technologies for energy storage and conversion,which is an important part of realizing sustainable clean energy for the ***,as emerging porous crystalline polymers,possess high specific surface areas,tunable pore structures,high crystallinity and tailorable *** features endow COFs with abundant active sites and fast electron transport channels,making them potentially efficient *** recent years,COF-based electrocatalysts have been widely developed for hydrogen evolution reaction(HER),hydrogen oxidation reaction(HOR),oxygen evolution reaction(OER),oxygen reduction reaction(ORR),nitrogen reduction reaction(NRR)and carbon dioxide reduction reaction(CO_(2)RR).In this review,design strategies of COF-based electrocatalysts are briefly summarized,including applying COF as supports,introducing active metals in COF,constructing two-dimensional conductive COF,formation of COF-based hybrid and pyrolysis of COF to obtain carbon ***,the recent research progress in COF-derived catalysts for specific electrocatalytic reactions is introduced ***,the outlook and challenges of future applications of COFs in electrocatalysis are highlighted.

关键词： covalent organic frameworks electrocatalyst catalytic performance catalytic kinetics energy conversion

Synthesis of Diverse 1,4-(Azaindole)[60] fullerenes via Transition- Metal Free Three-Component Coupling Reaction of Azaindoles, C_(60), and Bromoalkanes/Triphenylamines

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Chinese Journal of Chemistry 2023年第22期41卷 2975-2980页

作者： Xinmin Huang Zi-Zheng liu Jia-Qi cheng cheng-Yu Cao peng-cheng li Jun Xuan Fei li Department of Chemistry Anhui UniversityKey Laboratory of Structure and Functional Regulation of Hybrid Materials(Anhui University)Ministry of EducationAnhui Province Key Laboratory of Chemistry for Inorganic/Organic Hybrid Functionalized Materials and Key Laboratory of Functional Inorganic Materials of Anhui ProvinceHefeiAnhui 230601China Department of Chemistry University of Science and Technology of ChinaHefeiAnhui 230026China

A transition-metal free three-component coupling reaction of azaindoles,C_(60),and bromoalkanes/triphenylamines has been developed to provide an efficient access to diverse azaindole functionalized 1,4-C_(60) *** prot... 详细信息

关键词： Azaindoles Fullerenes 1,4-(Azaindole)fullerenes Transition-metal free Cross-coupling

Effects of sequential decay on collective flows and nuclear stopping power in heavy-ion collisions at intermediate energies

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Nuclear Science and Techniques 2023年第4期34卷 175-184页

作者： Kui Xiao peng-cheng li Yong-Jia Wang Fu-Hu liu Qing-Feng li State Key Laboratory of Quantum Optics and Quantum Optics Devices and Collaborative Innovation Center of Extreme Optics Institute of Theoretical PhysicsShanxi UniversityTaiyuan 030006China School of Science Huzhou UniversityHuzhou 313000China School of Nuclear Science and Technology Lanzhou UniversityLanzhou 730000China Institut für Theoretische Physik Goethe Universität FrankfurtFrankfurt am Main 60438Germany Institute of Modern Physics Chinese Academy of ScienceLanzhou 730000China

In this study, the rapidity distribution, collective flows, and nuclear stopping power in ^(197)Au+^(197)Au collisions at intermediate energies were investigated using the ultrarelativistic quantum molecular dynamics(UrQMD) model with GEMINI++ code. The UrQMD model was adopted to simulate the dynamic evolution of heavy-ion collisions, whereas the GEMINI++ code was used to simulate the decay of primary fragments produced by UrQMD. The calculated results were compared with the INDRA and FOPI experimental data. It was found that the rapidity distribution, collective flows, and nuclear stopping power were affected to a certain extent by the decay of primary fragments, especially at lower beam energies. Furthermore, the experimental data of the collective flows and nuclear stopping power at the investigated beam energies were better reproduced when the sequential decay effect was included.

关键词： Heavy-ion collisions Sequential decay effect Collective flow Nuclear stopping power

Collective flow and nuclear stopping in heavy ion collisions in Fermi energy domain

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Nuclear Science and Techniques 2018年第12期29卷 54-61页

作者： peng-cheng li Yong-Jia Wang Qing-Feng li Hong-Fei Zhang School of Nuclear Science and Technology Lanzhou University School of Science Huzhou University Institute of Modern Physics Chinese Academy of Sciences

The effects of the in-medium nucleon-nucleon(NN) elastic cross section on the observables in heavy ion collisions in the Fermi energy domain are investigated within the framework of the ultrarelativistic quantum molecular dynamics model. The results simulated using medium correction factors of F=σ_(NN)^(in-medium)/σ_(NN)^(free)=0.2,0.3,0.5,and the density-and momentum-dependent factor obtained from the FU3 FP1 parametrization are compared with the FOPI and INDRA experimental data. It is found that the calculations using the correction factors F=0.2 and 0.5 reproduce the experimental data(i.e.,collective flow and nuclear stopping) at 40 and 150 MeV/nucleon, respectively. Calculations with the FU3 FP1 parametrization can best fit these experimental data. These conclusions can be confirmed in both^(197)Au+^(197)Au and^(129)Xe+^(120)Sn.

关键词：重离子碰撞原子精力流动集体修正因素动力学模型试验性

Recent Advances in C_(2) Gases Separation and Purification by Metal-Organic Frameworks

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Chinese Journal of Structural Chemistry 2022年第11期41卷 31-44页

作者： Zhengyi Di Xinjing Zheng Yu Qi Heng Yuan cheng-peng li College of Chemistry Tianjin Key Laboratory of Structure and Performance for Functional MoleculesTianjin Normal UniversityTianjin 300387China State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou 350002.China

Separation of C_(2) gases(C_(2)H_(2)/C_(2)H_(4),C_(2)H_(6)/C_(2)H_(4) and C_(2)H_(2)/CO_(2))mixtures is one of the most important and energy-demanding processes in chemical *** separation methods(fine distillation separation and selective catalytic hydrogenation separation)have the shortages of high energy consumption and inefficient use of resources,affecting the achievement of peak carbon dioxide emissions and carbon neutrality *** based on adsorption is considered as one of the best ways to achieve low-energy ***,it is of great importance to synthesize materials that enable the effective separation and purification of C_(2) gases under mild *** an emerging class of porous materials,metal-organic frameworks(MOFs)show great promise in the field of gas separation and purification due to their ultra-high specific surface area,easily modifiable pore surfaces,structural designability and ***,we summarize recent research advances by use of MOFs sorbents for the separation and purification of C_(2) gases,including C_(2)H_(2)/C_(2)H_(4),C_(2)H_(6)/C_(2)H_(4) and C_(2)H_(2)/CO_(2).Relationship between structures and separation mechanism is also ***,challenges and possible research directions related to the further exploration are also discussed.

关键词： MOFs adsorption and separation C_(2)gas design and synthesis pore size

Effect of ceramic work rolls on surface roughness of rolled SUS304 ultra-thin strips

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Journal of Iron and Steel Research International 2024年第7期31卷 1704-1718页

作者： peng-cheng li Tao Wang Chen-chen Zhao Qi liu Qing-xue Huang College of Mechanical and Vehicle Engineering Taiyuan University of TechnologyTaiyuan 030024ShanxiChina Engineering Research Center of Advanced Metal Composites Forming Technology and Equipment of Ministry of Education Taiyuan University of TechnologyTaiyuan 030024ShanxiChina National Key Laboratory of Metal Forming Technology and Heavy Equipment Taiyuan University of TechnologyTaiyuan 030024ShanxiChina

Surface morphology and roughness are important parameters of surface quality of cold-rolled ultra-thin strip *** order to study the effect of Si_(3)N_(4) ceramic work rolls on the surface roughness of SUS304 ultra-thin strip,ABAQUS finite element model calculation,3D laser profilometry,and other methods were adopted based on the physical characteristics of Si_(3)N_(4) ceramic roll and 9Cr2MoV steel roll,like anti-flattening performance and oil *** surface morphology and roughness of SUS304 ultra-thin strip rolled by different material work rolls under oil lubrication conditions were *** results showed that under the rolling force of 10 kN,the maximum flattening amount of Si_(3)N_(4) ceramic roll was reduced by 35.14%compared to that of 9Cr2MoV steel *** reduction rate of SUS304 ultra-thin strip rolled by ceramic roll was 34.19%,while that rolled by steel roll was only 22%;Si_(3)N_(4) ceramic roll can further increase the number of alternating convex peaks and concave valleys in the rolled thin strip,reduce the profile steepness,reduce surface roughness,and enhance the planarization effect of surface micro-convex bodies,with improving surface quality and surface ***,the mechanism of Si_(3)N_(4) ceramic roll significantly improving the surface roughness of rolled SUS304 ultra-thin strip was proposed.

关键词： Ceramic work roll-Steel roll SUS304 ultra-thin strip Reduction Surface roughness