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On the Cayley-Bacharach property and the construction of vector bundles

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Science China mathematics 2011年第9期54卷 1891-1898页

作者： SUN Hao 1,2.1 department of mathematics and Statistics,{2. normal university,Wuhan 430079,China 2.department of mathematics,East China normal university,Shanghai 2.02.1,China department of mathematics and Statistics Huazhong Normal University Wuhan China department of mathematics East China Normal University Shanghai China

We study the Cayley-Bacharach property on complex projective smooth varieties of dimension n≥2.for zero dimensional subscheme defined by the zero set of the wedge of r-n + 1 global sections of a rank r≥n vector bund... 详细信息

关键词： Cayley-Bacharach property vector bundle reflexive sheaf k-very ample

A NEIGHBORHOOD UNION CONDITION FOR PANCYCliC GRAPHS

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Systems Science and Mathematical Sciences 1998年第4期11卷 289-298页

作者： li xiangwen({2. of mathematics, huazhong normal university, Wuhan 43.070, China)WEI Bing(Institute of Systems Science, Academia Sinica, Beijing 100080, China)

Let C be a 2.connected graph on > 2.31 venices. G is called pancyclic if itcontains a cycle of length I for every I such that 3 l n. In this paper we shall prove thatif IN(u) U N(v) Z (2. - 3)/3 for any nonadjacent pa... 详细信息

关键词： Neighborhood union cycle pancyclic graph

Output Rate of Atomic Four-Wave Mixing in Two-Component Bose-Einstein Condensate

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Communications in Theoretical Physics 2004年第5期41卷 695-698页

作者： li Jia-Hua~1 li Wei-Bing~1 PENG Ju-Cun~2.1 {2. of Physics,huazhong university of Science and Technology,Wuhan 430074,China2.{2. of Physics,Xiaogan normal university,Xiaogan 432.00,China department of Physics Huazhong University of Science and Technology Wuhan 430074 China department of Physics Xiaogan Normal University Xiaogan 432100 China

In this letter,following the proposal of Heurich et al.[***.A63(2.01)033605],we analyze anddiscuss output rate of atomic four-wave mixing in the two-component Bose-Einstein condensate under the condition ofthe steady *** results show that the magnitude of the signal beam increases with the increase of the intensityof the probe beam,up to a saturated value,then it decreases as the probe beam *** influence of theinteraction range on the signal beam is also *** particular,it is worth while pointing out that in contrast tothe previous solutions,our obtained analytical solutions are of very simple and explicit forms,which open the door forfurther investigating the related physical mechanisms.

关键词： atomic four-wave mixing steady state Bose-Einstein condensate

Image interpretation of weak-coupling N-mer adsorbate's STM system

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Chinese Science Bulletin 1997年第5期42卷 371-374页

作者： HUANG Xintang, Ql Shouren, li Xinjiao and li Yongping1 {2. of Physics, Central China normal university, Wuhan 43.070, China {2. of Solid State Electronics, huazhong university of Science and Technology, Wuhan 430074, China 2. {2. of Physics, university of Science and Technology of China, Hefei 2.002., China department of Physics Central China Normal University Wuhan China department of Solid State Electronics Huazhong University of Science and Techndogy Wuhan China department of Physics University of Science and Technology of China Hefei China

Up to now, there have been many indistinctive points in the image interpretation of scanning tunnelhng microscopy (STM) system, and the problems have attracted almost all STM scientists’ attention. In 1992. Kenkre proposed the new programme which describes the behaviour of the electrons moving in the STM tunnelling by the method of exciton dynamics, and the programme not only breaks through the restrictions of Tersoff-Hamann theory, but also can be applied conveniently to discussing the effects of the tip structure, adsorbate structure, substrate structure, temperature, tunneling voltage, and the degree of coherence of elec-

关键词： weak-coupling N-mer adsorbates STM image interpretation exciton dynamics method.

Stability of a Neutral Stochastic Functional Differential Equations

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Wuhan university Journal of Natural Sciences 2005年第6期10卷 957-960页

作者： li Bi-wen~1,2.. department of {2., Hubei normal university, Huangshi 435002. Hubei, China 2. department of {2., huazhong university of Science and Technology, Wuhan 430074, Hubei, China department of mathematics Hubei Normal University Huangshi Hubei China department of mathematics Huazhong University of Science and Technology Wuhan Hubei China

Sufficient condition for stochastic unifrom stability of a neutral stochastic functional differential equation is given, especially, new techniques are developed to cope with the neutral delay case, we obtained the sufficient condition for asymptotic stability of neutral stochastic differential delay equations. Due to the new techniques developed in this paper, the results obtained arc very general and useful. The theory developed here gives a unified treatment for various asymptotic estimates e.g. exponential and polynomial bounds.

关键词： Lyapunov function D operator It's formula stochastic unifrom stabillty asymptotic stability

Reexploring the upper bound for the chromatic number of graphs

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Progress in Natural Science:Materials International 2004年第3期 84-86页

作者： li Shuchao 1,2. * and MAO Jingzhong 1(1. department of Control Science and Engineering, {2. university of Science and Technology, Wuhan 430074, China 2. Laboratory of Nonlinear Analysis, department of mathematics, Central China normal university, Wuhan 430079, China) LaboratoryofNonlinearAnalysis DepartmentofMathematicsCentralChinaNormalUniversityWuhan430079China departmentofControlScienceandEngineering HuazhongUniversityofScienceandTechnologyWuhan430074China

The upper bound of the chromatic number of simple graphs is explored. Its original idea comes from Coffman, Hakimi and Schmeichel, who recently studied the chromatic number of graphs with strong conditions. In this pa... 详细信息

关键词： chromatic number clique number.

Influence of Calcium Sulfate State and Fineness of Cement on Hydration of Portland Cements Using Electrical Measurement

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Journal of Wuhan university of Technology(Materials Science) 2006年第4期21卷 141-145页

作者：魏小胜 department of Civil Engineering Huazhong University of Science and Technology Wuhan 430074 China

The influence of calcium sulfate state and fineness of cement on hydration of Portland cement was studied using electrical resistivity measurement. The bulk resistivity curve of the paste from the abnormal cement mainly with hemihydrate had a characteristic abnormal peak and rapid increase in early period. The resistivity measurement technique can be used to discriminate abnormal setting. For normal cement with gypsum, the increase in fineness of the Portland cement decreases the minimum resistivhy due to a higher ionic concentration and increases the 2. hour resistivity due to a reduction in macroscopic pore size. The setting time, compressive strength, pore structure of pastes made from different cements were carried out to compare the influence of water to cement ratio, calcium sulfate state and fineness. It is found that the electrical and mechanical properties are strongly affected by the initial porosity, the presence of hemihydrate or gypsum, and the fineness of cement.

关键词： false setting electrical resistivity fineness hydration

Algebraic characterization of RNA operations for DNA-based computation

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Progress in Natural Science:Materials International 2004年第11期 83-86页

作者： li Shuchao 1,2.*(1. Faculty of mathematics and Statistics, Central China {2. university, Wuhan 430079, China 2. department of Control Science and Engineering, huazhong university of Science and Technology, Wuhan 430074, China) FacultyofmathematicsandStatistics CentralChinaNormalUniversityWuhan430079China

Any RNA strand can be presented by a word in the language X *, where X=｛A,C,G,U｝. By encoding A as 010, C as 000, G as 111, and U as 101, the RNA operations can be considered as the performance of concatenation, union, reverse, complement, in terms of the algebraic characterization. The concatenation and union play the roles of multiplication and addition over some algebraic structures, respectively. The rest of the operations turn out to be the homomorphisms or anti-homomorphisms of these algebraic structures. Using this technique, we find the relationship among these RNA operations.

关键词： concatenation code monoid semiring.

Nowhere-zero 3-flows in Cayley graphs on generalized dihedral group and generalized quaternion group

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Frontiers of mathematics in China 2015年第2期10卷 293-302页

作者： liangchen li {2. li department of mathematics Huazhong Normal University Wuhan 430079 China department of mathematics Luoyang Normal University Luoyang 471022 China

Tutte conjectured that every 4-edge-connected graph admits a nowhere-zero 3-flow. In this paper, we show that this conjecture is true for Cayley graph on generalized dihedral groups and generalized quaternion groups, which generalizes the result of F. Yang and X. li [Inform. Process. Lett., 2.11, 111： 416-419]. We also generalizes an early result of M. Nanasiova and M. Skoviera [J. Algebraic Combin., 2.09, 30： 103-110].

关键词： Nowhere-zero 3-flow Cayley graph generalized dihedral group,generalized quaternion group