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A Class of Finite-Dimensional Representations of U_q(sl_2)

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Acta Mathematica Sinica,English Series 2013年第9期29卷 1703-1712页

作者： dong Ming CHENG dong su Department of Mathematics and Applied Mathematics He'nan University of Science and Technology

In order to study a class of finite-dimensional representations of Uq（sl2）, we deal with the quotient algebra Uq （m, n, b） of quantum group Uq（sl2） with relations Kr=1, Emr=b, Fnr=0 in this paper, where q is a root of unity. The algebra Uq（m, n, b） is decomposed into a direct sum of indecomposable （left） ideals. The structures of indecomposable projective representations and their blocks are determined.

关键词： Quantum group representation root of unity

Lightweight and large-scale rGO reinforced SiBCN aerogels with hierarchical cellular structures exposed to high-temperature environments

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Journal of Materials Science & Technology 2024年第12期179卷 145-154页

作者： Huijie Wang Zhiwei Chen dong su Key Laboratory of Advanced Ceramics and Machining Technology of Ministry of Education School of Materials Science and EngineeringTianjin UniversityTianjin 300350China

SiBCN ceramic aerogel is an ideal potential candidate for ultra-high temperature thermal insulation due to its unique microscopic pore structure combined with the excellent thermal stability of SiBCN ***,reduced graphene oxide(rGO)modified SiBCN aerogels(rGO/SiBCN)were prepared through solvothermal,freeze-casting and pyrolysis,and the dimension of the aerogel is up toΦ130 mm×28 *** density of the rGO/SiBCN aerogel is as low as 0.024 g/cm^(3) and the microstructural regulation is achieved by controlling the rGO content in the *** hierarchical cellular structure endows the aerogel with a high specific surface area(148.6 m^(2)/g)and low thermal conductivity(0.057 W m^(-1) K^(-1)).The 10 mm-thick sample exhibits excellent thermal insulation and ablation resistance,as evidenced by its ability to reduce the temperature from~1100℃to~180℃under the intense heat of a butane ***,benefiting from the ultrahigh-temperature stability of SiBCN,the rGO/SiBCN aerogel exhibits good thermal stability up to 1200℃in argon and short-oxidation resistance at 800℃in ***-fore,the rGO/SiBCN aerogel with superior overall performance could expand its practical application in high-temperature thermal insulation under extreme environments.

关键词： rGO/SiBCN Lightweight Large size Hierarchical cellular structure Thermal insulation

Resonance scattering characteristics of double-layer spherical particles

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Particuology 2012年第1期10卷 117-126页

作者： Xuejin dong Mingxu su Xiaoshu Cai Institute of Particle and Two-Phase Flow Measurement University of Shanghai for Science and Technology Shanghai 200093 China

Based on the principle of ultrasonic resonance scattering, sound-scattering characteristics of double-layer spherical particles in water were numerically studied in this paper. By solving the equations of the scat- tering matrix, the scattering coefficient determined by the boundary conditions can be obtained, thus the expression for the sound-scattering function of a single double-layer spherical particle can be derived. To describe the resonance scattering characteristics of a single particle, the reduced scattering cross section and reduced extinction cross section curves were found through numerical calculation. Similarly, the numerically calculated sound attenuation coefficient curves were used to depict the resonance scattering characteristics of monodisperse and poIydisperse particles. The results of numerical calculation showed that, for monodisperse particles, the strength of the resonance was mainly related to the particle size and the total number of particles; while for polydisperse particles, it was primarily affected by the particle size, the coverage of the particle size distribution and the particle concentration.

关键词： UltrasonicResonance scatteringDouble-layerPolydisperseVisco-elastic

Molecular Dynamics Simulation of Microstructure Transitions in a Large-Scale Liquid Metal Al System During Rapid Cooling Processes

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Chinese Physics Letters 2002年第8期19卷 1144-1147页

作者： Liu Rang-su, dong Ke-Jun Department of Physics Hu"nan University Department of Chemistry Hu"nan University School of Materials Science and Engineering The University of New South Wales

We perform a molecular dynamics simulation of microstructure transitions in a large-scale system consisting of 400 000 atoms of liquid metal Al by the Clare supercomputer. A cluster-type index method is proposed to describe the structures of various short-range-order clusters in the liquid system. It is demonstrated that the icosahedron cluster (12 0 12 0) plays the most important role in the microstructure transition and that some larger clusters (containing more than 130 atoms) are formed in the system during the rapid cooling processes. It is obvious that the larger clusters are formed by means of combining some middle clusters, and that the middle clusters are formed with several smaller clusters. However, the larger clusters are not formed to be the multi-shell configuration as shown in the mass spectrum analysis of the cluster configurations of Al obtained by gaseous deposition, ionic spray methods and so on. This result can be used to explain the essential distinction between the cluster configurations of Al formed in two different ways

关键词： Molecular dynamics

New insights into plasmonic hot-electron dynamics

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Light(Science & Applications) 2024年第11期13卷 2427-2430页

作者： Dangyuan Lei dong su Stefan A.Maier Department of Materials Science and Engineering Center for Functional Photonicsand Hong Kong Branch of National Precious Metals Material Engineering Research CentreCity University of Hong Kong83 Tat Chee AvenueHong Kong S.A.R.999077China School of Physics and Astronomy Monash UniversityClayton 3800 VICAustralia Blackett Laboratory Imperial College LondonLondon SW72AZUK

Recent advances in understanding the hot-electron dynamics in plasmonic nanostructures have significantly impacted a variety of plasmonically powered physical,chemical,and even biological *** insights into their quant... 详细信息

关键词： dynamics plasmon insight

In‐situ structural characterizations of electrochemical intercalation of graphite compounds

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Carbon Energy 2019年第2期1卷 200-218页

作者： Na Li dong su Beijing National Laboratory for Condensed Matter Physics Institute of PhysicsChinese Academy of SciencesBeijingChina Frontier Institute of Science and Technology jointly with College of Science Xi’an Jiaotong UniversityXi’anShaanxiChina

Graphite carbon has been successfully used for the anode materials of secondary ion batteries due to its capability of accommodating ions between graphite *** intercalation dynamics intrinsically determine the performance of the *** this review,we summarize recent research progresses of structural characterizations on graphite intercalation in electrochemical devices,especially on the in‐situ study on the intercalations of Li/Na/K ions,AlCl4−and other anions,or *** techniques,including X‐ray,electron microscopy,Raman,neutron scattering,nuclear magnetic resonance,and optical microscopy provide direct information of the reaction dynamics and help to understand the factors affecting the electrochemical performances of metallic ion batteries.

关键词： graphite intercalation in‐situ characterization Li/Na/K/Al ions batteries

Theoretical Investigation on Hyperfine Structures of Perfluoropolyether Radicals

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Chemical Research in Chinese Universities 2011年第1期27卷 117-122页

作者： dong su-li LIU Ya-jun Key Laboratory of Theoretical and Computational Photochemistry Ministry of Education College of Chemistry Beijing Normal University Beijing 100875 P. R. China

The geometries of CF3OCF2, CF3OCFCF3 and CF3OCF2CF2 radicals were investigated by density functional theory（DFT） method. The calculated results indicate that all the three radicals have pyramidal shapes at their centers, and the aC is one top of the pyramids. Based on the DFT optimized geometries, the hyperfine coupling constants（hfec＇s） of the 19F atoms of the three radicals were calculated by B3LYP, MP2（full） and QCISD（full） methods. The calculated values agree with the experimental values, especially for the a values of Fa, the a values are 125.6× 10 -4, 104.2× 10 - 4, and 83.2×10 -4 T of CF3OCF2, CF3OCFCF3 and CF3OCF2CF2, respectively. These results better explain the experimental observation.

关键词： Perfluoropolyether radical Hyperfine coupling constant Density functional theory

On interest-rate risk management of postal savings bureau

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The Journal of China Universities of Posts and Telecommunications 2007年第1期14卷 115-121页

作者： DU Chong-dong LI su-man Finance Department Shijiazhuang Post and Telecommunication Technical College Shijiazhuang 050021 China

This article analyzes interest-rate risks faced by the postal savings bureau （PSB） based on the complete balance sheet. It presents the extended gap model and the extended duration gap model to measure the interest-rate risk, and discusses the inner balance-sheet strategies and the off-balance-sheet strategies to manage the interest-rate risks.

关键词： interest-rate risk gap model duration gap model,financial engineering PSB

GA-Based Model Predictive Control of Semi-Active Landing Gear

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Chinese Journal of Aeronautics 2007年第1期20卷 47-54页

作者： WU dong-su GU Hong-bin LIU Hui College of Civil Aviation Nanjing Universityy of Aeronautics and AstronauticsNanjing 210016 China

Semi-active landing gear can provide good performance of both landing impact and taxi situation, and has the ability for adapting to various ground conditions and operational conditions. A kind of Nonlinear Model Predictive Control algorithm （NMPC） for semi-active landing gears is developed in this paper. The NMPC algorithm uses Genetic Algorithm （GA） as the optimization technique and chooses damping performance of landing gear at touch down to be the optimization object. The valve＇s rate and magnitude limitations are also considered in the controller＇s design. A simulation model is built for the semi-active landing gear＇s damping process at touchdown. Drop tests are carried out on an experimental passive landing gear systerm to validate the parameters of the simulation model. The result of numerical simulation shows that the isolation of impact load at touchdown can be significantly improved compared to other control algorithms. The strongly nonlinear dynamics of semi-active landing gear coupled with control valve＇s rate and magnitude limitations are handled well with the proposed controller.

关键词： landing gear semi-active control: nonlinear model predictive control impact load genetic algorithm