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Variational construction of unbounded orbits in Lagrangian systems

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Science China mathematics 2010年第3期53卷 617-624页

作者： CHENG Chong-Qing 1, & LI Xia 2.1 department of mathematics, Nanjing {2., Nanjing 2.0093, China 2.department of mathematics, Suzhou {2. of Science and Technology, Suzhou 2.5001, China department of mathematics Nanjing University Nanjing China department of mathematics Suzhou University of Science and Technology Suzhou China

We show the existence of unbounded orbits in perturbations of generic geodesic flow in T2.by a generic periodic potential. Different from previous work such as in Mather (1997), the initial values of the orbits obtain... 详细信息

关键词： positive definite Lagrangian variational method unbounded orbit

Synthesis and crystal structure of complex of Ce(NO_3)_3 with N-(3-methyl-pyridin-2.yl)-formimidoyl-(3-methyl-pyridin-2.yl) hydrazone

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Science China Chemistry 2004年第3期47卷 251-256页

作者： JIANG Yinzhi1,2.& HU Weixiao1 1. department of Pharmaceutical Science, Zhejiang university of Technology, Hangzhou 310032. China 2. department of Applied Chemistry, Zhejiang Institute of Science and Technology, Hangzhou 310033, China department of Pharmaceutical Science Zhejiang University of Technology Hangzhou China department of Applied Chemistry Zhejiang Institute of Science and Technology Hangzhou China

The reaction of 3,6-di-(3-methyl-pyridin-2.yI)-s-tetrazine (DMPTZ, II) with CeIII salt [Ce(NO3)3 · 6H2.] generates a new ligand, N-(3-methyl-pyridin-2.yl)-formimidoyl-(3-methyl-pyridin-2.yl) hydrazone (L), and forms a new complex: a mononuclear complex [Ce(L)(NO3)2.(H2.)3] · NO3 (III). Crystal data for III: space group P-1, with a = 0.7133(4) nm, b = 1.1139(2. nm, c = 1.4572.3) nm, α= 102.13(2.°, β= 99.81(3)°, γ= 91.10(3)°, Z = 2. V = 1113.6(7) nm3, μ = 2.12. mm?1 and F(000) = 630. L acts as a tri-dentate chelating ligand in III. There are 10 coordination sites around Ce3+ of III, which are respectively occupied by seven oxygen atoms (four from two nitrate anions and three from three H2. molecules) and three nitrogen atoms (all from L). The cerium atom and three chelating nitrogen atoms are coplanar. The mechanism of the metal assisted decomposition is discussed briefly.

关键词： rare earth, complex, crystal structure, synthesize, 3,6-bis (3-methyl-pyridin-2.yl)-s-tetrazine, N-(3-methyl-pyridin- 2.yl)-formimidoyl-(3-methyl-pyridin-2.yl) hydrazone.

OPTIMIZATION OF ADAPTIVE DIRECT METHOD FOR APPROXIMATE SOLUTION OF INTEGRAL EQUATIONS OF SEVERAL VARIABLES

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Acta Mathematica Scientia 2004年第2期24卷 228-234页

作者：马万房艮孙 departmentofmathematics BeijingNormalUniversityBeijing100875China

This paper determines the exact error order on optimization of adaptive direct methods of approximate solution of the class of Fredholm integral equations of the second kind with kernel belonging to the anisotropic So... 详细信息

关键词： Integral equations direct methods anisotropic sobolev classes

Theoretical study on thermal decomposition of azoisobutyronitrile in ground state

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Science China Chemistry 2004年第5期47卷 373-380页

作者： SUN Chengke1,2. ZHAO Hongmei1 & LI Zonghe1 1. department of Chemistry, Beijing Normal university, Beijing 100875, China 2. department of Chemistry, Qujing Normal College, Qujing 655000, China Dept. of Chem. Beijing Normal Univ. Beijing 100875 China Dept. of Chem. Qujing Normal Coll. Qujing 655000 China

The thermal decomposition mechanisms of azoisobutyronitrile (AIBN) in the ground state have been investigated systematically. Based on the potential energy surfaces (PES) of various possible dissociation paths obtained using the semiempirical AM1 method with partial optimization, the density function theory B3LYP/6-311G* method was employed to optimize the geometric parameters of the reactants, the intermediates, the products and the transition states, which were further confirmed by the vibrational analysis. The obtained results show that the re- action process of the two-bond (three-body) simultaneous cleavage Me2.CN)C─ N=N─ C(CN)Me2. 2.e2.CN)C?+N2.is much more favorable than the reaction process of the two one- bond asynchronous cleavage Me2.CN)CN=N─C(CN)Me2.? Me2.CN)CN=N?+ Me2.CN)C?? Me2.CN)C?+ N2. It was suggested that the electron shrinking effect of double bond (─N=N─) in AIBN and the stabilities of the Me2.CN)C?radical as well as N2.molecule are main factors of leading to the reaction proceeding in the former pathway. The calculation results were consistent with all the experimental facts.

关键词： azoisobutyronitrile, radicals, thermal decomposition, density function theory (DFT).

The integration of methanogenesis with denitrification and anaerobic ammonium oxidation in an expanded granular sludge bed reactor

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Journal of Environmental Sciences 2003年第3期15卷 423-432页

作者： ZHANG Dai-jun 1,2.(1. department of Environmental Science, Chongqing university, Campus A, Chongqing 400044, China 2. Key Laboratory for the Southwest China Resources Exploitation and Environmental Disaster Control Engineering, Ministry of Education, China.) department of Environmental Science Chongqing University Campus A 重庆 400044

The integration of methanogenesis with denitrification and anaerobic ammonium oxidation(ANAMMOX) was studied in an expanded granular sludge bed(EGSB) reactor in this work. Experimental results from the continuous treatment of wastewater with nitrite and ammonium, which lasted for 107 days, demonstrated that wastewater with high nitrite and ammonium could be anaerobically treated in an expanded granular sludge bed reactor. More than 91% to 97% of COD were removed at up to about 3.9 g COD/(L·d) of COD volumetric loading rate. More than 97% to 100% of nitrite was denitrified at up to about 0.8 g NO -_2.N/(L·d), which is 16 times higher than that in a conventional activated sludge system with nitrification/denitrification(0.05 gN/(L·d)). No dissimilatory reduction of nitrite to ammonium occurred in the process. However, maximum of about 40% ammonium was found to be lost. Batch tests of 15 days with sludge from the reactor showed that 100% of nitrite was denitrified completely, and about 3% of ammonium was removed when only ammonium (34.3 mg/L) and nitrite(34.3 mg/L) were added into the sludge suspension medium. Furthermore, about 15% of ammonium amounts were lost with organic COD addition. It suggested that the methanogenesis in the system could enhance ANAMMOX because of intermediate hydrogen produced during methanogenesis.

关键词： methanogenesis denitrification ANAMMOX EGSB reactor

Geometric characterizations for variational minimization solutions of the 3-body problem

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Chinese Science Bulletin 1999年第18期44卷 1653-1655页

作者： LONG Yiming and ZHANG Shiqing1. Nankai Institute of mathematics , Nankai university , Tianjin 300071 , China 2. {2. of Applied mathematics, Chongqing university, Chongqing 400044, China Associate Member of the ICTP. Nankai Institute of mathematics Nankai University Tianjin China department of Applied mathematics Chongqing University Chongqing China

For any given positive masses it is proved that the variational minimization solutions of the 3-body problem in 3 or 2.are precisely the planar equilateral triangle circular solutions found by J. Lagrange in 1772. and that the variational minimization solutions of the circular restricted 3-body problem in 3 or 2.are also planar equilateral triangle circular solutions.

关键词： 3-body problem variational minimization equilateral triangle circular solution.

Brassinosteroid signal trans-duction: An emerging picture

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Chinese Science Bulletin 2003年第18期48卷 1906-1912页

作者： WANG Qiaomei1 & MA Ligeng2.1. department of Horticultural Science, Zhejiang university, Hangzhou 31002., China 2. department of Biology, hebei Normal university, Shijiazhuang 050016, China Correspondence should be addressed to Ma Ligeng (e-mail: ligeng.ma @yale.edu) department of Horticultural Science Zhejiang University Hangzhou 310029 China department of Biology Hebei Normal University Shijiazhuang 050016 China

Steroid hormones play essential roles in animal growth and development. Steroid signaling in animal system is focused on the direct gene regulation response mediated by its nuclear receptors. Recently, steroid hormones are also found in plants. Identification of BRI1 — a critical compo-nent of the plasma-membrane steroid receptor complex, and the related signal transduction pathway mediated by the membrane receptor have revealed an elementary picture of BR signaling from the cell surface perception to the activa-tion of BR-responsive nuclear genes.

关键词： plants Brassinosteroids signal transduction BRI1 cross talk.

The truncated Second Main Theorem and uniqueness theorems

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Science China mathematics 2010年第3期53卷 605-616页

作者： CHEN ZhiHua 1 , RU Min 2. & YAN QiMing 1 1 department of mathematics, Tongji {2., Shanghai 2.0092. China 2.department of mathematics, {2. of Houston, Houston, TX 772.4, USA department of mathematics Tongji University Shanghai China department of mathematics University of Houston Houston USA

In this paper, we first establish a truncated Second Main Theorem for algebraically nondegenerate holomorphic mappings from the complex plane into a complex projective variety V intersecting hypersurfaces. We then prove some uniqueness results for meromorphic mappings. The result of Demailly about a partial solution to the Fujita’s conjecture is used.

关键词： value distribution theory uniqueness theorem meromorphic mappings Fujita’s conjecture

NONOSCILLATION RESULTS FOR A CLASS OF THIRD ORDER NONLINEAR DIFFERENTIAL EQUATIONS

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Applied mathematics and Mechanics(English Edition) 2002年第10期23卷 1170-1175页

作者： Pakize Temtek 1, Aydn Tiryaki 2.(1 department of mathematics, Faculty of Arts and Science, Erciyes {2., 38039, Kayseri, Turkey 2.department of mathematics, Faculty of Arts and Science, Gazi {2., Teknikokullar 06500 Ankara, Turke department of mathematics Faculty of Arts and Science Erciyes University Kayseri Turkey department of mathematics Faculty of Arts and Science Gazi University Ankara Turkey

Sufficient conditions for the nonoscillatory solutions of a class of third order nonlinear differential equations are presented. The results obtained generalize some criteria given by Parhi. In some special cases, som... 详细信息

关键词： differential equation nonlinear nonoscillatory solution Parhi criteria