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The influence of laser pulse on the photoabsorption spectra of Li atom in strong external field

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Science china(Physics,Mechanics & Astronomy) 2006年第2期49卷 178-186页

作者： WANG Dehua1.& lin {1.2.1. School of Physics and Electronic Engineering, Yantai {1. {2., Yantai 2.402., china 2. Department of Physics, shandong normal university, jinan 2.001., china 1. School of Physics and Electronic Engineering Yantai Normal University Yantai 264025 China 2. Department of Physics Shandong Normal University Jinan 250014 China

Using the time-dependent perturbation theory and the calculation formula of the single- and double-pulse absorption spectra of the atom in strong external fields, we calculate the single- and double-pulse absorption spectra of Li atom in strong magnetic field for different pulse widths. The results show that a pulse of some width can reduce the contribution of the short period closed orbits and eliminate the contribution of the long period orbits. Compared with the single-pulse absorption spectra, we found that for some phase differences, the double-pulse laser absorption spectra are strengthened; while for others, they are reduced. Therefore, we can use the pulse laser to control the oscillation of the absorption spectra and obtain the optimization object.

关键词： laser pulse closed orbit absorption spectra.

The dynamical properties of Rydberg hydrogen atom near a metal surface

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Science china(Physics,Mechanics & Astronomy) 2005年第6期48卷 667-675页

作者： GE Meihua1. ZHANG Yanhui1. WANG Dehua2. DU Mengli3 & {2. 1. College of Physics and Electronics,{1.,{2., china 2. Department of Mathematics and Physics, shandong Institute of Architecture and Engineering,{2., china 3. Institute of Theoretical Physics, Chinese Academy of Sciences, Beijing 1.0080, china 1. College of Physics and Electronics Shandong Normal University 250014 Jinan China 2. Department of Mathematics and Physics Shandong Institute of Architecture and Engineering 250014 Jinan China 3. Institute of Theoretical Physics Chinese Academy of Sciences 100080 Beijing China

The dynamical properties of Rydberg hydrogen atom near a metal surface are presented by using the methods of phase space analysis and closed orbit theory. Transforming the coordinates of the Hamiltonian, we find that the phase space of the system is divided into vibrational and rotational region. Both the Poincaré surface of section and the closed orbit theory verify the same conclusion clearly. In this paper we choose the atomic principal quantum number as n = 2.. The dynamical character of the exited hydrogen atom depends sensitively on the atom-surface distance d. When d is sufficiently large, the atom-surface potential can be expressed by the traditional van der Waals force and the system is integrable. When d becomes smaller, there exists a critical value dc. For d > dc, the system is near-integrable and the motion is regular. While chaotic motion appears for d < dc, and the system tends to be non-integrable. The trajectories become unstable and the electron might be captured onto the metal surface.

关键词： Rydberg hydrogen atom, van der Waals interaction, Poincaré surface of section, closed orbit theory, chaos.

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 {2., Wuhan Hubei 430079,{1. 2.{2., jinan shandong 2.001.,{1. Huazhong Agricultural university Wuhan Hubei 430079 China shandong {1. {2. 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

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. Department of Geography,{1.,{1.,{2. 2. Department of Geography, jinan university, jinan 2.0001.{2. 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

Synthesis and structural characterization of Zn_3N_2.powder

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Science china(Physics,Mechanics & Astronomy) 2005年第2期48卷 201-210页

作者： ZONG Fujian1. MA Honglei1. XUE Chengshan2. ZHUANG Huizhao2. ZHANG Xijian1. MA Jin1. JI Feng1.& XIAO Hongdi1.1. School of Physics and Microelectronics, shandong {1., {2. 2.01.0, china 2. Institute of Semiconductor,{12., jinan 2.001., china School of Physics and Microelectronics Shandong University Jinan 250100 China Institute of Semiconductor Shandong Normal University Jinan 250014 China

Zinc nitride (Zn3N2. powder has been synthesized through the nitridation reaction of Zn powder with NH3 gas (at the flow rate of 500 ml/min) at the nitridation temperature of 600℃ for 1.0 min. X-ray diffraction (XRD) indicates that Zn3N2.is cubic in structure with the lattice constant being a = 0.9788 nm. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) show that Zn3N2.powder has surface morphology of various types. X-ray photoelectron spectroscopy (XPS) shows the differences in chemical bonding states between Zn3N2.and ZnO, and confirms the formation of N–Zn bonds. Observation through high resolution transmission electron microscopy (HRTEM) also indicates that the computer simulation of the structure of Zn3N2.is consistent with the structural model put forward by Partin.

关键词： nitridation, Zn3N2 powder, structure, XRD, SEM, TEM, HRTEM, XPS.

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.{2.,{1.,{2. 2. Chinese Research Academe of Environmental Sciences, Beijing 1.001.,{2. shandong {1. {2. 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 dec{1.es 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-{1.earity 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 800-2.0}, Shanghai 2.1.00, china 2. Department of Physics,{1.,{2., china 3. shandong Institute of Architecture and Engineering,{2., china 1. Shanghai Institute of Optics and Fine Mechanics Chinese Academy of Sciences P. O. Box 800-211 201800 Shanghai China 2. Department of Physics Shandong Normal University 250014 Jinan China 3. shandong Institute of Architecture and Engineering 250014 Jinan China

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.

Diffusion and Oxidation Wear of PCBN Tool based on Thermodynamics

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Journal of Wuhan university of Technology(Materials Science) 2010年第2期25卷 265-271页

作者：邵芳 Binzhou Vacational College School of Mechanical Engineering Shandong University

The rules of diffusion wear and oxidation wear for PCBN cutting tools were analyzed based on thermodynamics theory. Dissolution concentrations in typical normal workpice materials of PCBN tool material at different temperature were then calculated. Diffusion reaction rules in high temperature were developed and analyzed using the Gibbs free energy criterion. The machining tests were conducted using the PCBN tools at different cutting speeds of 50, 95,1.0 and 1.0 m/min, feed of 0.1. 0.2.and depth of cut of 0.1. 0.8, 1. and 1.5 mm respectively on a PUMA300LM numerically-controlled lathe. It was found that the theoretical results were uniform with the experimental data, and the results will provide useful references for tool material design and selection.

关键词： thermodynamics PCBN tool diffusion wear oxidation wear

Moment bounds for IID sequences under sublinear expectations

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Science china Mathematics 2011年第10期54卷 2155-2160页

作者： HU Feng1.2.1.epartment of Mathematics,Qufu {2. {1.,Qufu 2.31.5,{2. 2.chool of Mathematics,shandong {1.,jinan 2.01.0,{2. 1. Department of Mathematics Qufu Normal University Qufu 273165 China2. School of Mathematics Shandong University Jinan 250100 China

With the notion of independent identically distributed(IID) random variables under sublinear expectations introduced by Peng,we investigate moment bounds for IID sequences under sublinear expectations. We obtain a moment inequality for a sequence of IID random variables under sublinear expectations. As an application of this inequality,we get the following result:For any continuous functionsatisfying the growth condition |(x) | C(1.+ |x|p) for some C > 0,p 1.depending on ,the central limit theorem under sublinear expectations obtained by Peng still holds.

关键词： moment bound sublinear expectation IID random variables G-normal distribution central limit theorem