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Recurrence spectra of He atoms in strong external fields

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Science china(Physics,Mechanics & Astronomy) 2004年第4期47卷 477-484页

作者： LIN Shenglu1. LI Hongyun1. WANG Dehua2. ZHAO Wenli1.& GAO Feng1.1. {1. of Physics, shandong {2. University, jinan 2.001., china 2. {1. of Mathematics and Physics, shandong Institute of Architecture and Engineering, jinan 2.001., china department of Physics Shandong Normal University Jinan China department of Mathematics and Physics Shandong Institute of Architecture and Engineering Jinan China

By employing a model potential including the electron exchange energy, we extend the semiclassical closed orbit theory to study the multielectron atoms. Using special region-splitting consistent and iterative method, we figure out the closed orbits in the corresponding classical system and calculate the recurrence spectra of triplet helium atoms in parallel electric and magnetic fields at scaled energy ε=?0.03,n≈40,n=0. The core-scattering effects have been taken into account, which lead to more peaks in the spectra. It has also been confirmed by means of the direct comparison between the spectral portrait in such a plot and those of hydrogen case. In order to compare the theoretic results with experiment, we investigate the closed orbits and recurrence spectra of helium atoms for the similar exchange potential but applied only by single electric field at scaled energy ε=?2.7 case. The spectra are in good agreement with the experimental observation. We conclude that our model is correct and it is necessary to consider the exchange effect for determining the photoabsorption spectra of multielectron atoms in strong external fields.

关键词： exchange potential, recurrence spectra, semiclassical closed orbit theory, core-scattering.

Prediction for RNA planar pseudoknots

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Progress in Natural Science:Materials International 2007年第6期17卷 717-724页

作者： Li Hengwu1.2. Zhu Daming1. Liu Zhendong1.and Li Hong2.1. School of Computer Science and Technology, shandong University, jinan 2.01.0,{2. 2. department of Computer, shandong Economic University, jinan 2.001.,{2.) School of Computer Science and Technology Shandong University Jinan 250100 China department of Computer Shandong Economic University Jinan 250014 China

Based on m-stems and semi-extensible structure, a model is presented to represent RNA planar pseudoknots, and corresponding dynamic programming algorithm is designed and implemented to predict arbitrary planar pseudoknots and simple non-planar pseudoknots with O(n4) time and O(n3) space. The algorithm folds total 2.5 sequences in the Pseudobase database, and the test results indicate that the algorithm has good accuracy, sensitivity and specificity.

关键词： algorithm RNA secondary structure pseudoknot dynamic programming.

Formation and Evolution of Ancient Lakes on South Coast Plain of Laizhou Bay

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Chinese Journal of Population,Resources and Environment 2005年第4期3卷 26-32页

作者： Han Mei 1. Zhou Baohua 2. Yang Peilin 1.Gao Guiqin 1.& Zhang Weiying 1.1. {1. of Geography, shandong {2. University, jinan 2.001., china 2. {1. of Geography, jinan University, jinan 2.0001. china department of Geography Shandong Normal University Jinan 250014 China department of Geography Jlnan University Jinan 250001 China

Based on the data of historical geography, the analysis of the stratigraphic section, and the textual research of place names and satellite photographic interpretations, the authors study the formation and evolution of ancient lakes on the south coast plain of Laizhou Bay where there were once three lakes: Judian Lake, Qingshuibo Lake and Biehua Lake. All the lakes formed 6000 years ago evolved from the lagoons near the estuary and went through two periods, the golden age in the Middle Holocene and the shrinking age in the Late Holocene. The disappearance of the lakes resulted from the drying climate, the migration of the river courses and the activities of human beings. Among the three reasons, the migration of the river courses is the main one.

关键词： ancient lake cause historical evolution south coast plain of Laizhou Bay

Exploration of Science Parks

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Chinese Journal of Population,Resources and Environment 2005年第1期3卷 55-59页

作者： Xiong Huibing & Sun Nengli 1.2.1. Huazhong Agricultural University, Wuhan Hubei 430079,{1. 2. shandong {2. University, jinan shandong 2.001.,{1. Huazhong Agricultural University Wuhan Hubei 430079 China shandong {1. University Jinan Shandong 250014 China

Science parks have developed greatly in the world, whereas empirical researches have showed that science parks based on linear model cannot guarantee the creation of innovation. Hi-tech innovation is derived from flow and management of information. The commercial and social interactions between in-parks and off-park firms and research institutions act as the key determinant for innovation. Industrial clustering is the rational choice for further developing Chinese science parks and solving some problems such as the lack of clear major industries and strong innovation sense, etc.

关键词： science parks hi-tech industry industrial clusters

Comparison of temporal and Spatial Characteristics of Ozone Pollution at Ground Level in the Eastern china

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Chinese Journal of Population,Resources and Environment 2006年第3期4卷 51-57页

作者： Liu Houfeng1.2.1. {1. normal University,{2., china 2. Chinese Research Academe of Environmental Sciences, Beijing 1.001.0} china shandong {1. University Jinan 250014 China Chinese Research Academe of Environmental Sciences Beijing 100012 China

Monitoring data from ozone（O3） automatic stations in three typical cities with different climatic areas in the southern and northern parts of eastern china are used to analyze temporal and spatial characteristics of ozone pollution at ground level. The results show that ozone pollution level has distinct regional differences and the concentration in the suburbs is higher than that in the urban areas. The seasonal variation of ozone concentration in different climatic areas is greatly affected by the variation of precipitation. Ozone concentration in Shenyang and Beijing , in the temperate zone, has one perennial peak concentration, occurring in early summer, May or June. Ozone concentration in Guangzhou, in sub-tropical zone, has two peak values year round. The highest values occur in October and the secondary high value in June. The ozone season in the south is longer than that in the north. The annual average daily peak value of ozone concentrations in different climates usually occur around 3 pm. The diurnal variation range of ozone concentration declines with the increase of latitude. Ozone concentration does not elevate with the increase of traffic flow. Ozone concentration in Guangzhou has a distinct reverse relation to CO and NOx. This complicated non-linearity indicates that the equilibrium of ozone photochemical reaction has regional differences. Exceeding the rate of Beijing＇s lh ozone concentration is higher than that of Guangzhou, whereas the average 8h ozone level is lower than that of Guangzhou, indicating that areas in low latitude are more easily affected by moderate ozone concentrations and longer exposure. Thus, china should work out standards for 8h ozone concentration.

关键词： ozone temporal and spatial characteristics 8h concentrations weekly variation

The optical near-field speckles and their first order statistics on the basis of the integral equations of electromagnetic field

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Science china(Physics,Mechanics & Astronomy) 2004年第3期47卷 365-380页

作者： CHENG Chuanfu1, 2. SONG Hongsheng2. LIU Chunxiang2. REN Xiaorong2. ZHANG Ningyu3, TENG Shuyun1 & XU Zhizhan1 1. Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, P. O. Box 800-2.1, Shanghai 2.1800, china 2. department of Physics, {2. normal University, jinan 2.001., china 3. {2. Institute of Architecture and Engineering, jinan 2.001., china Shanghai Institute of Optics and Fine MechanicsChinese Academy of SciencesShanghaichina department of Physics{1. {2. Universityjinanchina shandong Institute of Architecture and Engineering{1.{2.

From Helmholtz equation of the harmonic electromagnetic waves, the integral equations of the light field at the medium boundaries are obtained by use of the Green's theorem and are discretized into linear equation set with the values of the light field and its derivative as the unknowns. On solving the linear equation set, we realize the rigorous computations of the light fields at the boundaries. Then the intensities of the light waves scattered by the random self-affine fractal surfaces in the optical near-field are calculated, and the propagation characteristics, the evolutions of the contrast and the intensity probability density function of the near-field speckles are studied in detail. The near-field speckles are much different from the conventional speckles in the diffraction regions and in the imaging systems. There are obvious local fluctuations in the intensity distributions of the near-field speckles and such fluctuations disappear after propagating a distance of one wavelength from the medium surfaces. For the random surfaces with smaller lateral correlation lengths, the speckle contrasts approach the saturation values and the speckle fields approach Gaussian distribution within the near-field, while for the random surfaces with larger lateral correlation lengths, such evolutions become comparatively slow.

关键词： speckle, near-field optics, first order statistics, Green's function.

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. {1. of Chemistry, Beijing normal University, Beijing 1.0875,{2. 2. {1. of Chemistry, Qujing normal College, Qujing 655000,{2. 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/6-31.G* 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).

K-uniformly rotund spaces and k-uniformly smooth spaces

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Chinese Science Bulletin 1998年第2期43卷 92-95页

作者： Suyalatu 1.and WU Congxin 2.1. {1. of Mathematics,Inner Mongolia normal University, Huhhot 01.02.,{2. 2. {1. of Mathematics, Harbin Institute of Technology, Harbin 1.0006,{2. department of Mathematics Inner Mongolia Normal University Huhhot China department of Mathematics Harbin Institute of Technology Harbin China

The conception of k_uniform smoothness (KUS) is introduced. It is the extension of the conception of uniform smoothness. It is proved that the k_uniform smoothness and Sullivan’s K_uniform rotundity (KUR) are the daul notions. X+* is a KUR space if and only if X is a KUS space, X+* is a KUS space if and only if X is a KUR space. If X is a KUS space, then X is a (K+1.US space. It is also proved that the KUS space includes the Nan’s k_strongly smooth space.

关键词： K_uniform smoothness K_uniform convexity.

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. {1. of Mathematics, Beijing normal University, Beijing 1.0875,{2. 2. {1. of Mathematics, Neijiang Teacher's College, Neijiang 641.1.0}{2.) 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