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The Cauchy problem of generalized Landau-Lifshitz equation into S^n

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Science China Mathematics 2013年第2期56卷 283-300页

作者： song chong YU Jie School of Mathematical Sciences Xiamen University Academy of Mathematics and Systems Science Chinese Academy of Sciences

In this paper,we study the Cauchy problem of an integrable evolution system,i.e.,the n-dimensional generalization of third-order symmetry of the well-known Landau-Lifshitz *** rewriting this equation in a geometric form and applying the geometric energy method with a forth-order perturbation,we show the global well-posedness of the Cauchy problem in suitable Sobolev spaces.

关键词： generalized Landau-Lifshitz geometric energy method

Broadcast-Based Spatial Queries

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Journal of Computer Science & Technology 2005年第6期20卷 811-821页

作者： Kwang-Jin Park Moon-Bae song chong-Sun Hwang Department of Computer Science and Engineering Korea University 5-1 Anam-Dong Seongbuk-Ku Seoul 136-701 Korea

Indexing techniques have been developed for wireless data broadcast environments, in order to conserve the scarce power resources of the mobile clients. However, the use of interleaved index segments in a broadcast cycle increases the average access latency for the clients. In this paper, the broadcast-based spatial query processing methods （BBS） are presented for the location-based services. In the BBS, broadcasted data objects are sorted sequentially based on their locations, and the server broadcasts the location dependent data along with an index segment. Then, a sequential prefetehing and caching scheme is designed to reduce the query response time. The performance of this scheme is investigated in relation to various environmental variables, such as the distributions of the data objects, the average speed of the clients and the size of the service area.

关键词： broadcasting location-aware caching prefetching mobile computing

Ab initio Study of the Potential Energy Surface and Product Branching Ratios for Reaction of O（^1D） with C2H5CI

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Chinese Journal of Chemical Physics 2009年第1期22卷 87-96页

作者： chong-fu song Zhi-mei Tian Quan-xin Li Tian-jing He Department of Chemistry Fuyang Teacher's College Fuyang 236041 China Department of Chemical Physics University of Science and Technology of China Hefei 230026 China

The potential energy surface of O（^1D）＋C2H5Cl reaction was studied using QCISD（T）/6- 311＋＋G（d,p）//MP2/6-31G（d,p） method. The calculations reveal an insertion-elimination mechanism. The insertion reaction of O（^1D） and C2H5Cl produces two energy-rich intermediates, IM1 and IM2, which subsequently decompose into various products. The calculations of the branching ratios of various products formed through the two intermediates were carried out using RRKM （Rice-Ramsperger-Kassel-Marcus） theory at the collision energies of 0, 20.9, 41.8, 62.7, 83.6, 104.5, and 125.4 kJ/mol. HCl is the main decomposition product for IM1; CH2OH is the main decomposition product for IM2. Since IM1 is more stable than IM2, HCl is probably the main product of the O（^1D）＋C2H5Cl reaction.

关键词： C2H5Cl Branching ratio Rate constant

Effect of orbital errors on the geosynchronous circular synthetic aperture radar imaging and interferometric processing

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Journal of Zhejiang University-Science C(Computers and Electronics) 2011年第5期12卷 404-416页

作者： Lei-lei KOU Xiao-qing WANG Mao-sheng XIANG Jin-song chong Min-hui ZHU National Key Laboratory of Microwave Imaging Technology Institute of Electronics Beijing 100190 China Graduate University of Chinese Academy of Sciences Beijing 100190 China

The geosynchronous circular synthetic aperture radar (GEOCSAR) is an innovative SAR system,which can produce high resolution three-dimensional (3D) images and has the potential to provide 3D deformation *** an orbit altitude of approximately 36 000 km,the orbit motion and orbit disturbance effects of GEOCSAR behave differently from those of the conventional spaceborne *** this paper,we analyze the effects of orbit errors on GEOCSAR imaging and interferometric ***,we present the GEOCSAR imaging geometry and the orbit errors model based on perturbation ***,we give the GEOCSAR signal formulation based on imaging geometry,and analyze the effect of the orbit error on the output focused *** interferometric processing on the 3D reconstructed images,the relationship between satellite orbit errors and the interferometric phase is *** demonstrate the effects of orbit errors on the GEOCSAR images,interferograms,and the *** conclusions are that the required relative accuracy of orbit estimation should be at centimeter level for GEOCSAR imaging at L-band,and that millimeter-scale accuracy is needed for GEOCSAR interferometric processing.

关键词： Geosynchronous circular synthetic aperture radar (GEOCSAR) Orbit error Imaging Interferometric processing

Preparation of High Surface Area, Large Pore Volume Alumina by Using β-Cyclodextrin as a Non-surfactant Template

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Chinese Chemical Letters 2006年第9期17卷 1239-1242页

作者： Lai Jun WANG Ming Fen WEN Yu Shan LI Dong YANG Jing CHEN chong Li song Laboratory 201 Institute of Nuclear and New Energy Technology Tsinghua University Beijing 102201

A series of alumina samples were prepared using β-cyclodextrin as the non-surfactant template. These samples were characterized by XRD, BET and TEM. The results showed that the alumina samples prepared using β-cyclodextrin template had the higher surface areas （124-484 m^2/g）, larger pore volumes （0.7-1.27 mL/g） and more thermal stability than samples prepared without using β-cyclodextrin.

关键词： Al2O3 β-cyclodextrin templating method specific surface area.

Synthesis and Self-assembling of Coumarin-based Low-molecular Weight Organogelators

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Chemical Research in Chinese Universities 2009年第2期25卷 178-182页

作者： CHEN Guo-jun XUE Peng-chong LU Ran song Dong-po BAO Chun-yan XU Ting-hua ZHAO Ying-ying College of Chemistry Jilin University Changchun 130012 P. R. China

Four coumarin derivatives（4a-4d） with different alkoxy chains were synthesized. It was found that compound 4d showed a better gelation ability than the other compounds, for example, it could self-assemble into organogels in various organic fluids via ultrasound treatment or heating-cooling process, whereas compound 4c could only gel in a few mixed solvents and compounds 4a, 4b could not form organogel. The results from fluorescent and FT-IR spectra indicate that π-π interaction had an effect on the formation of the organogels of compound 4d besides H-bonding and van der Waals interaction, which were the driving forces for the self-assembling of compound 4c in gel state. The gel of compound 4d in toluene could emit strong fluorescence under UV irradiation and the [2＋2] cyclo-addition was suggested by ^1H NMR and fluorescence spectroscopy. This light-sensitive organogel might find application in optical materials.

关键词： Coumarin Organogelator Self-assembling [2+2] Cyclo-addition

四气门汽油机进气与压缩过程缸内流场的大涡模拟

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内燃机工程 2010年第3期31卷 48-51页

作者：曾文宋崇林沈阳航空工业学院动力与能源工程学院沈阳110136 天津大学内燃机燃烧学国家重点实验室天津300072

通过修改发动机多维CFD计算程序KIVA-3V,建立了内燃机缸内冷态流场的大涡模拟(LES)计算模型。利用此模型对4气门汽油机进气与压缩过程中缸内流场进行了详细分析,并与k-ε模型进行了比较。研究结果表明:与采用k-ε模型计算时相比,采用LE... 详细信息

通过修改发动机多维CFD计算程序KIVA-3V,建立了内燃机缸内冷态流场的大涡模拟(LES)计算模型。利用此模型对4气门汽油机进气与压缩过程中缸内流场进行了详细分析,并与k-ε模型进行了比较。研究结果表明:与采用k-ε模型计算时相比,采用LES计算时显示了更为复杂的湍流结构;采用LES计算时除了能够得到有序的大尺度涡团结构外,还能捕捉到大量不规则的小涡团结构,而采用k-ε模型计算时基本上捕捉不到不规则的小涡团结构。

关键词：内燃机湍流大涡模拟涡团结构 k-ε模型

Study on the Properties of Nanometer CeO_2 Doped with Zr^(4+),La^(3+),Pr^(3+)

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Journal of Materials Science & Technology 2004年第3期20卷 357-360页

作者： Mingfen WEN Bo YU Qiuping WANG chong1i song Jing CHEN Institute of Nuclear Energy Technology,Tsinghua University,Beijing 102201,China Tsinghua Univ Inst Nucl Energy Technol Beijing 102201 Peoples R China

Different nanometer CeO_2-ZrO_2 mixed oxides doped with lanthanum or praseodymium were prepared by coprecipi-tation. The characteristics of all mixed oxides were tested by XRD, SEM, TEM, and XPS. XRD results showed thatall oxides were formed solid solution with CaF_2 structure at low temperature and had good thermal stability. MoreCe^(4+) ions were rich on the surface by XPS, which were beneficial to oxygen storage. The particle mediun sizes (d_(50))of all oxides powders were approximately 10～20 nm by small angle scattering goniometer. When doped Zr^(4+) inCeO_2, the specific surface areas were improved at low or high temperature. The area of Ce_(0.6)Zr_(0.3)La_(0.04)Pr_(0.06)O_2powder had excess 110 m^2/g after calcining at 923 K for 4 h, even calcined at 1273 K for 4 h, the area was up to65 m^2/g.

关键词： Ceria-zirconia Solid solution Nanometer High surface area

A Single Photon Produces General W State of N 0ubits and Its Application

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Communications in Theoretical Physics 2007年第7期48卷 75-78页

作者： MEI Di LI chong song He-Shan Department of Physics,Dalian University of Technology,Dalian 116023,China Department of Physics Dalian University of Technology Dalian 116023 China

Based on the Wu's scheme[***,***,***,and ***,***.A 73(2006)012310],we prepare the general N-qubit W *** find that the concurrence of two qubits in general N-qubit Wstate is only related to their coefficients and we successfully apply the general N-qubit W state to quantum state transferand quantum state prepare like that in two-qubit system.

关键词： N-qubit W state concurrence quantum state transfer