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Accurate studies on the full vibrational energy spectra and molecular dissociation energies for some electronic states of N_(2.molecule

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Science china(physics,Mechanics & Astronomy) 2005年第4期48卷 385-398页

作者： REN Weiyi1,2. SUN Weiguo1, HOU Shilin3 & FENG Hao4 1. Institute of physics, College of Chemical Engineering, Sichuan University, Chengdu 610065, china 2. Institute of Theoretical physics, Xihua normal University, Nanchong 637002. china 3. department of physics, china Oceanography University, Qingdao 2.6003, china 4. College of physics, Sichuan University, Chengdu 610065, china 1. Institute of physics College of Chemical Engineering Sichuan University 610065 Chengdu China 2. Institute of Theoretical physics Xihua Normal University 637002 Nanchong China 3. department of physics China Oceanography University 266003 Qingdao China 4. College of physics Sichuan University 610065 Chengdu China

It is usually very difficult to directly obtain molecular dissociation energy De and all accurate high-lying vibrational energies for most diatomic electronic states using modern experimental techniques or quantum theories, and it is also very difficult to give accurate analytical expression for diatomic molecular dissociation energy. This study proposes a new analytical formula for obtaining accurate molecular dissociation energy based on the LeRoy and Bernstein’s energy expression in dissociation limit. A set of full vibrational energy spectra for some electronic states of N2.molecule are studied using the algebraic method (AM) suggested recently, and the corresponding accurate molecular dissociation energies are evaluated using the proposed new formula and high-lying AM vibrational energies. The results show that the AM spectra and the new theoretical dissociation energies agree excellently with experimental data, and thereby providing a new physical approach to generating accurate dissociation energies for electronic states of diatomic molecules.

关键词： vibrational energy, dissociation energy, nitrogen molecule, algebraic method.

Arbuscular mycorrhizal for-mation of crucifer leaf mus-tard induced by flavonoids apigenin and daidzein

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Chinese Science Bulletin 2004年第12期49卷 1254-1261页

作者： DONG Changjin1,2.& ZHAO Bin1 1. State Key Laboratory of Agricultural Microbiology, Huazhong Agri- cultural University, wuhan 430070, china 2. {2. of Biology, Hubei normal University, Huangshi 435002. china 1. State Key Laboratory of Agricultural Microbiology Huazhong Agricultural University 430070 Wuhan China 2. department of Biology Hubei Normal University 435002 Huangshi China

Flavonoids from legume root secretion may probably act as signal molecules for expression of Rhizobial “nod” nodulation genes and AM fungal symbiotic gene. Leaf mustard is a non-mycorrhizal plant; it does not contain fla- vonoids and other signal molecules. AM fungi could not in- fect the roots of leaf mustard and form a symbiont in nature, when it was treated with flavonoids (apigenin or daidzein). The results of trypan blue staining showed that two kinds of AM fungi (G. intraradices and G. mosseae) successfully in- fected the roots of non-mycorrhizal plant leaf mustard. AM fungi grew towards and colonized the roots of leaf mustard, producing young spores and completing the course of life. AM fungi are the only one kind of fungi with ALP activity. The result of ALP staining has also proved that AM fungi infected successfully the roots of leaf mustard. AM fungi (G. intraradices and G. mosseae) that existed in the roots of non-mycorrhizal plant leaf mustard were probed by nested PCR and special molecular probes. The above-mentioned proof chains have fully proved that flavonoids induced AM fungi (G. intraradices and G. mosseae) to infect non-my- corrhizal plant and establish symbiotic relationship.

关键词：非菌根植物免疫十字花科叶芥菜芹甙元大豆黄酮类黄酮灌木菌根真菌嵌套PCR trypan蓝色染色

Energy Efficient Beacon Discovering Scheme for Node Localization in Wireless Sensor Networks

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wuhan University Journal of Natural Sciences 2010年第4期15卷 303-307页

作者： LIU Xinxin1,2. ZHAO Erdun3, CHEN Kun2.1. School of Computer, wuhan University, wuhan 430072. Hubei,{2. 2. wuhan Digital Engineering Research Institute, wuhan 430074, Hubei,{2. 3. department of Computer Science, Huazhong normal University, wuhan 430079, Hubei,{2. School of Computer Wuhan University Wuhan Hubei China wuhan Digital Engineering Research Institute Wuhan Hubei China department of Computer Science Huazhong Normal University Wuhan Hubei China

Efficient sensor node localization is a crucial part of many location-dependent applications that utilize wireless sensor networks (WSNs). To cope with the problem of insufficient bea-con node for localization,we design a beacon discovery protocol in this paper that helps the blind node to find beacons nearby and present an energy efficient scheme for the beacon that receives the request from a blind node to adjust its radio range. We obtain the relationship between the mean energy consumption with adjust-ment number by the mathematical analysis. Numerical results show that great energy saving is achieved when the optimal ad-justment number is adopted.

关键词： localization wireless sensor networks energy- efficient radio range adjustment

Molecular modeling and spectroscopic studies on the binding of guaiacol to human immunoglobulin

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Science china Chemistry 2006年第6期49卷 550-559页

作者： HE Wenying1,2. YAO Xiaojun1, LIU Pengjun2. GAO Zhenxia2.& HU Zhide1 1. department of Chemistry, Lanzhou University, Lanzhou 730000, china 2. department of Chemistry, Hainan normal University, Hainan 571158, china 1. department of Chemistry Lanzhou University Lanzhou 730000 China 2. department of Chemistry Hainan Normal University Hainan 571158 China

The fluorogenic property of guaiacol was exploited for the first time to analyze the interaction with target protein as a probe by molecular modeling, fluorescence, circular dichroism (CD) and Fourier transform infrared (FT-IR) spectroscopy. Molecular docking was performed to reveal the possible binding mode or mechanism and suggested that guaiacol can strongly bind to human immu- noglobulin (HIgG). It is considered that guaiacol binds to HIgG mainly by a hydrophobic interaction and there are two hydrogen bond interactions between the drug and the residues LEU 80 and ASP 65, which is in good agreement with the results from the experimental thermodynamic parameters (the enthalpy change △H0 and the entropy change △S0 were calculated to be 65.55 kJ·mol-1 and 132.95 J·mol-1·K-1 according to the Vant’ Hoff equation). Data obtained by the fluorescence spectroscopy indicated that binding of guaiacol with HIgG leads to dramatic enhancement in the fluorescence emission intensity along with significant occurrence of efficient Frster resonance energy transfer (FRET) from the residue of HIgG to the protein bound guaiacol. From the low value of fluorescence anisotropy (r = 0.06), it is argued that the probe molecule is located in the motionally unrestricted environment of the protein. The alterations of protein’s secondary structure in the presence of guaiacol in aqueous solution were quantitatively calculated by the evidences from FT-IR and CD spectroscopes.

关键词： guaiacol, human immunoglobulin, molecular modeling, fluorescence enhancement, Fourier transform infrared (FT-IR) spectroscopy, circular dichroism (CD).

Modulation on the collective response behavior by the system size in two-dimensional coupled cell systems

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Science china(physics,Mechanics & Astronomy) 2006年第3期49卷 304-312页

作者： ZHANG Jiqian1, SHEN Chuansheng1,2.& CUI Zhifeng1 1. College of physics and Electronic Information, Anhui normal University, Wuhu 2.1000,{2. 2. department of Educational Technology, Anqing Teachers College, Anqing 2.6011,{2. College of physics Electronic Information Anhui Normal University Wuhu 241000 China department of Educational Technology Anqing Teachers College Anqing 246011 China

By the intracellular calcium ionic minimal model proposed by Berridge, we investigated the collective response of two-dimensional (N×N) coupled cell systems to the external stimulation using numerical simulation methods. With a coupled intensity fixed and an appropriate coupled cell number chosen, the kinetic system size resonance was discovered. At the same time, it was found that the system size responding to the external stimulation for different coupled intensities transferred too, especially when the coupled intensity increased, the range of the corresponding system size extended. These phe- nomena illustrate that the coupled cell number and the coupled intensity can play con- structive roles in noisy coupled systems, by which the biology system would probably improve its capability to respond to the external stimulation.

关键词： cell coupling,collective response,system size resonance

Stochastic bi-resonance induced by external noise for Ca^2. signaling in hepatocytes

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Science china Chemistry 2005年第4期48卷 286-291页

作者： ZHANG Jiqian1,2.HOU Zhonghuai1 & XIN Houwen1 1.department of Chemical physics,University of Science and Technology of{2.,Hefei 2.002.,china 2.College of physics and Electronic Information,Anhui normal University,Wuhu 2.1000,china 1. department of Chemical physics University of Science and Technology of China 230026 Hefei China 2. College of physics and Electronic Information Anhui Normal University 241000 Wuhu China

The influence of external noise on intracellular Ca2. oscillations dynamics in a single cell of rat hepatocytes is *** coherence of noise-induced intracellular Ca2. oscillations reached two maxima for multiple external noise intensity,indicating the occurrence of external noise stochastic bi-resonance (SBR).This phenomenon is compared with our previous result that was induced by internal ***,the deterministic bifurcation character of the system was also discussed.

关键词： stochastic bi-resonance, environment fluctuation, calcium oscillations.

Gas kinetic algorithm for flows in Poiseuille-like microchannels using Boltzmann model equation

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Science china(physics,Mechanics & Astronomy) 2005年第4期48卷 496-512页

作者： LI Zhihui1,2. ZHANG Hanxin1 & FU Song2.⒈ National Laboratory for CFD, Hypervelocity Aerodynamics Institute,china Aerodynamics Research and Development Center,Mianyang 62.000,china {2. of Engineering Mechanics,Tsinghua University,Beijing 100084,china 1. National Laboratory for CFD Hypervelocity Aerodynamics Institute China Aerodynamics Research and Development Center 621000 Mianyang China 2. department of Engineering Mechanics Tsinghua University 100084 Beijing China

The gas-kinetic unified algorithm using Boltzmann model equation have been extended and developed to solve the micro-scale gas flows in Poiseuille-like micro-channels from Micro-Electro-Mechanical Systems (MEMS). The numerical modeling of the gas kinetic boundary conditions suitable for micro-scale gas flows is presented. To test the present method, the classical Couette flows with various Knudsen numbers, the gas flows from short microchannels like plane Poiseuille and the pressure-driven gas flows in two-dimensional short microchannels have been simulated and compared with the approximate solutions of the Boltzmann equation, the related DSMC results, the modified N-S solutions with slip-flow boundary theory, the gas-kinetic BGK-Burnett solutions and the experimental data. The comparisons show that the present gas-kinetic numerical algorithm using the mesoscopic Boltzmann simplified velocity distribution function equation can effectively simulate and reveal the gas flows in microchannels. The numerical experience indicates that this method may be a powerful tool in the numerical simulation of micro-scale gas flows from MEMS.

关键词： Boltzmann model equation, discrete velocity ordinate method, finite-difference scheme, Couette flow, Poiseuille flow, gas flow in short-microchannel.

Constructing super Gabor frames:the rational time-frequency lattice case

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Science china Mathematics 2010年第12期53卷 3179-3186页

作者： LI ZhongYan 1 & HAN DeGuang 2. 1 department of Mathematics and physics, North{2. Electric Power University, Beijing 102.06,{2. 2.department of Mathematics, University of central Florida, Orlando, FL 32.16, USA 1. department of Mathematics and physics North China Electric Power University Beijing 102206 China2. Department of Mathematics University of Central Florida Orlando FL 32816 USA

For a time-frequency lattice Λ = A Z d × B Z d , it is known that an orthonormal super Gabor frame of length L exists with respect to this lattice if and only if |det( AB) | = 1 L . The proof of this result involves various techniques from multi-lattice tiling and operator algebra theory, and it is far from constructive. In this paper we present a very general scheme for constructing super Gabor frames for the rational lattice case. Our method is based on partitioning an arbitrary fundamental domain of the lattice in the frequency domain such that each subset in the partition tiles R d by the lattice in the time domain. This approach not only provides us a simple algorithm of constructing various kinds of orthonormal super Gabor frames with flexible length and multiplicity, but also allows us to construct super Gabor (non-Riesz) frames with high order smoothness and regularity. Several examples are also presented.

关键词： super Gabor frame orthonormal super frame full rank lattice tiles

Dimension and measure theoretic entropy of a subshift in symbolic space

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Chinese Science Bulletin 1997年第14期42卷 1193-1196页

作者： CHEN Ercai and XIONG Jincheng1. department of Astronomy, Nanjing University, Nangjing 2.0093, china 2. department of Mathematics, South china normal University, Guangzhou 510631, china department of Astronomy Nanjing University Nangjing China department of Mathematics South China Normal University Guangzhou China

1 Definitions and resultsWITH the development of the theory of dynamical systems and fractal geometry, one provedthat symbolic dynamics is a powerful tool to study chaos and fractals. It is useful to study thefractal characteristics of symbolic dynamics. In the present note we shall point out the relationbetween the dimension and measure theoretic entropy of any subshift in symbolic space. Weprove here that the Bowen’s formula for Hausdorff dimension holds without Markov struc-ture. A variational principle for dimension is obtained.

关键词： symbolic space subshift measure theoretic entropy dimension.