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Existence of the solutions and the attractors for the large-scale atmospheric equations

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science china Earth sciences 2006年第6期49卷 650-660页

作者： HUANG Haiyang1 & GUO Boling2.1. department of Mathematics, beijing normal university,{2., china 2. Institute of Applied Physics and Computational Mathematics, beijing 100080, china 1. department of Mathematics Beijing Normal University Beijing 100875 China 2. Institute of Applied Physics and Computational Mathematics Beijing 100080 China

In this paper, firstly, the proper function space is chosen, and the proper expression of the operators is introduced such that the complex large-scale atmospheric motion equations can be described by a simple and abstract equation, by which the definition of the weak solution of the atmospheric equations is made. Secondly, the existence of the weak solution for the atmospheric equations and the steady state equations is proved by using the Galerkin method. The existence of the non-empty global attractors for the atmospheric equations in the sense of the Chepyzhov-Vishik’s definition is obtained by constructing a trajectory attractor set of the atmospheric motion equations. The result obtained here is the foundation for studying the topological structure and the dynamical behavior of the atmosphere attractors. Moreover, the methods used here are also valid for studying the other atmospheric motion models.

关键词： atmosphere equations, weak solution, trajectory attractor, global attractor, equilibrium.

Implementation of a multiple round quantum dense coding using nuclear magnetic resonance

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science china(Physics,Mechanics & Astronomy) 2005年第6期48卷 706-715页

作者： ZHANG Jingfu1, XIE Jingyi2. WANG Chuan1, DENG Zhiwei3, LU Zhiheng4, & LONG Guilu1,5 1. Key Laboratory For Quantum Information and Measurements of MOE, department of Physics, Tsinghua university, {2. 100084,china 2. department of materials science and Engineering, beijing normal university, beijing 100875, china 3. Testing and Analytical Center, beijing normal university, beijing 100875,china 4. department of Physics, beijing normal university, beijing 100875, china 5. Key Laboratory For atomic and Molecular Nanosciences, Tsinghua university, {2. 100084,china 1. Key Laboratory For Quantum Information and Measurements of MOE Department of Physics Tsinghua University 100084 Beijing China 2. department of materials {2. and Engineering Beijing Normal University 100875 Beijing China 3. Testing and Analytical Center Beijing Normal University 100875 Beijing China 4. department of Physics Beijing Normal University 100875 Beijing China 5. Key Laboratory For Atomic and Molecular Nanosciences Tsinghua University 100084 Beijing China

A multiple round quantum dense coding scheme based on the quantum phase estimation algorithm is proposed and implemented in a three qubit nuclear magnetic resonance (NMR) quantum computer. Using an m + 1 qubit system, Bob can transmit one of 2.+1 messages to Alice, through manipulating only one qubit and exchanging it between Alice and Bob for m rounds. The information capacity is enhanced to m + 1 bits as compared to m bits in a classical scheme. The scheme has been demonstrated in NMR system, and the experimental results show a good agreement between theory and experiment.

关键词： quantum dense coding, multiple round, nuclear magnetic resorance

An equality on Hochschild homology groups

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Chinese science Bulletin 1997年第8期42卷 624-627页

作者： ZHANG Pu and LIU Shaoxue1. department of Mathematics, university of {2. and Technology of china, Hefei 2.002., china 2. department of Mathematics, beijing normal university, beijing 100875, china department of Mathematics University of Science and Technology of China Hefei China department of Mathematics Beijing Normal University Beijing China

LET A be finite-dimensional algebra over field k,and Ae the enveloping algebra of A,i.e.Ae=A kAop,where Aop is the opposite algebra of *** A-bimodule has a natural left Ae-module structure as follows:

关键词： finite-dimensional algebra Hochschild homology groups dimensions.

The kink-soliton and antikink-soliton in quasi-one-dimensional nonlinear monoatomic lattice

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science china(Physics,Mechanics & Astronomy) 2005年第2期48卷 150-157页

作者： XU Quan1 & TIAN Qiang2.1. Scientific and Technological Office, Daqing Teacher College, Daqing 163712. china 2. department of Physics ,{2., beijing 100875, china Scientific and Technological Office Daqing Teacher College Daqing 163712 China department of Physics Beijing Normal University Beijing 100875 China

The quasi-one-dimensional nonlinear monoatomic lattice is analyzed. The kink-soliton and antikink-soliton are presented. When the interaction of the lattice is strong in the x-direction and weak in the y-direction, the two-dimensional (2.) lattice changes to a quasi-one-dimensional lattice. Taking nearest-neighbor interaction into account, the vibration equation can be transformed into the KPI, KPII and MKP equation. Considering the cubic nonlinear potential of the vibration in the lattice, the kink-soliton solution is presented. Considering the quartic nonlinear potential and the cubic interaction potential, the kink-soliton and antikink-soliton solutions are presented.

关键词： two-dimensional nonlinear lattice, quasi-one-dimensional nonlinear lattice, kink-soliton, antikink-soliton.

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,{2., china 2. department of Chemistry, Qujing normal College, Qujing 655000, china 1. department of Chemistry Beijing Normal University 100875 Beijing China 2. department of Chemistry Qujing Normal College 655000 Qujing 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).

Optimal reactions for the synthesis of superheavy nucleus ^(2.0)Hs

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science china(Physics,Mechanics & Astronomy) 2006年第6期49卷 641-648页

作者： LIU Zuhua1,3 & BAO Jingdong1,2.1. Key Laboratory of Beam Technology and Material Modification of Ministry of Education, beijing normal university, beijing 100875,{2. 2. Physics department, beijing normal university, beijing 100875,{2. 3.{2. Institute of Atomic Energy, beijing 102.13,{2. Key Laboratory of Beam Technology Material Modification of Ministry of Education Beijing Normal University Beijing 100875 China Physics department Beijing Normal University Beijing 100875 China china Institute of Atomic Energy Beijing 102413 China

The superheavy nucleus 2.0Hs is expected to be a “double-magic” deformed nucleus. We have calculated its cross sections of evaporation residue for the reactions 2.8Cm(2.Mg,4n)2.0Hs, 2.4Pu(30Si,4n)2.0Hs, 2.8U(36S,4n)2.0Hs and 2.6Ra(48Ca,4n)2.0Hs using a two-parameter Smoluchowski equation. It is found from our results that 2.6Ra(48Ca,4n)2.0Hs and 2.8U(36S,4n)2.0Hs are two optimal reactions for the synthesis of the superheavy nucleus 2.0Hs due to their large negative Q-values.

关键词： diffused fusion barrier,Smoluchowski equation,superheavy nuclei.

ENERGY FLOWS IN COMPLEX ECOLOGICAL SYSTEMS:A REVIEW

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Journal of Systems science & Complexity 2009年第3期22卷 345-359页

作者： Jiang ZHANG department of Systems science,School of Management,{2. normal university,{2. 100875,china. department of Systems science School of Management Beijing Normal University Beijing 100875 China

Energy flow drives the complex systems to *** allometric scaling as the universalenergy flow pattern has been found in different scales of ecological *** reflects the generalpower law relationship between flow and *** underlying mechanisms of energy flow patterns areexplained as the branching transportation networks which can be regarded as the result of systematicoptimization of a biological target under *** flows in the ecological system may bemodelled by the food web model and population dynamics on the *** paper reviews thelatest progress on the energy flow patterns,explanatory models for the allometric scaling and modellingapproach of flow and network evolution dynamics in ***,the possibility of generalizingthese flow patterns,modelling approaches to other complex systems is discussed.

关键词： Allometric scaling energy flow flows in complex systems food web.

Electroluminescent properties of three ternary europium complexes with different phenanthroline derivatives

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science china Chemistry 2004年第4期47卷 326-334页

作者： BIAN Zuqiang1,2. GAO Deqing1, GUAN Min1, XIN Hao1, LI Fuyou1, HUANG Chunhui1, WANG Kezhi2.& JIN Linpei2.1. State Key Laboratory of Rare Earth materials Chemistry and Applications, Peking university, {2. 100871, china 2. department of Chemistry, beijing normal university, beijing 100875, china 1. State Key Laboratory of Rare Earth materials Chemistry and Applications Peking University 100871 Beijing China 2. department of Chemistry Beijing Normal University 100875 Beijing China

Three ternary Eu(III) complexes with general formula of Eu(DBM)3LN (DBM = dibenzoylmethanate, and LN (N = 1-3 ) stand for three different 1,10-phenanthroline derivatives) have been synthesized for vacuum deposition films-based electroluminescent devices. The complex Eu(DBM)3L3 (L3 = 2.phenyl-3-[3-(carbazol-9-yl)propyl]imidazo[4,5-f]1,10-phenan-throline) was designed with an effort to combine the electron-transporting phenanthroline platform and the hole-transporting carbazole group into one molecule expecting to improve both electron and hole transporting properties simultaneously. The results show that the variation of the neutral ligands in Eu(III) mixed ligand complexes is a simple and effective approach to the improvement in the thermal stability, PL and EL properties of materials. A double-layer device with the configuration of ITO/TPD (50 nm)/Eu(DBM)3L3 (50 nm)/Mg0.9Ag0.1 (2.0 nm)/Ag (100 nm) exhibited Eu(III)-based pure red emission with a maximum brightness of 561 cd/m2.at 16 V, and an onset driving voltage of 8 V. A device with the configuration of ITO/TPD (50 nm)/[Eu(DBM)3L3 (5 nm):BCP (5 nm)]4/BCP (2. nm)/AIQ (10 nm) Mg0.9Ag0.9 (110 nm)/Ag (100 nm) gave high efficient and pure red light emission with a luminance of 1419 cd/m2. Keywords dibenzoylmethane - electroluminescence - lanthanide - N ligands

关键词： dibenzoylmethane electroluminescence lanthanide N ligands

Fuzzy controllers based on some fuzzy implication operators and their response functions

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Progress in Natural science:materials International 2004年第1期14卷 16-21页

作者： LI Hongxing 1*, YOU Fei 1 and PENG Jiayin 2.1. department of Mathematics, beijing normal university,{2., china 2. department of Mathematics, Neijiang Teacher's College, Neijiang 641112. china) beijing normal Univ Dept Math Beijing 100875 Peoples R China

The fuzzy controllers constructed by 2. fuzzy implication operators based on CRI algorithm and their response functions are discussed. The conclusions show that the fuzzy controllers constructed by 9 fuzzy implication operators are universal approximators to continuous functions and can be used in practical fuzzy control systems. And these 9 fuzzy implication operators except for Einstein operator intersection are all the adjoint pairs of some fuzzy implication operators. Besides, there are 3 other fuzzy controllers formed by fuzzy implication operators being regarded approximately as fitted functions.

关键词： fuzzy implication operators CRI algorithm fuzzy controllers response functions universal approximators