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Electronic Structure of New Superconducting Perovskite MgCNi3

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Journal of Materials Science & Technology 2004年第2期20卷 203-205页

作者： Li CHEN, Hua LI and Liangmo MEIphysics and Microelectronic School, shandong {2., jinan 2.0100, china department of physics, Linyi Teachers {2., shandong 2.6005, china Phys. and Microelectron. Sch. Shandong Univ. Ji'nan 250100 China Dept. of Phys. Linyi Teachers Univ. Linyi 276005 China

The electronic structures of new superconducting perovskite MgCNi3 and related compounds MgCNi2. (T=Co, Fe, and Cu) have been studied using MS-Xa method. In MgCNi3, the main peak of density of states is located below the Fermi level and dominated by Ni d. From the results of total energy calculations, it was found that the number of Ni valence electron decreases faster for the Fe-doped case than that for the Co-doped case. The valence state of Ni changes from +1.43 in MgCNi2.o to +3.02.in MgCNi2.e. It was confirmed that Co and Fe dopants in MgCNi3 behave as a source of d-band holes and the suppression of superconductivity occurs faster for the Fe-doped case than that for the Co-doped case. In order to explain the fact that Co and Fe dopants in MgCNi3 behave as a source of d-band holes rather than magnetic scattering centers that quench superconductivity, we have also investigated the effects of electron (Cu) doping on the superconductivity and found that both electron (Cu) doping and hole (Co, Fe) doping quench superconductivity exist. Comparing with the hole (Co) doping, there was no much difference between Cu and Co doping. This suggests that Co and Fe doping do not act as magnetic impurity.

关键词： Electronic structure Superconductivity Density of states

The Existence of Periodic Orbits for Nonlinear Impulsive Differential Systems

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Communications in Nonlinear Science and Numerical Simulation 1999年第1期4卷 50-53页

作者： Xilin FU Jiangang QI and Yansheng LIU (department of Mathematics, shandong normal university,{2., china) department of Mathematics Shandong Normal University Jinan 250014 China

In this paper, we gave the necessary and sufficient condition for the existence of the periodic solutions of nonlinear impulsive differential systems by using a special function and study the stable properties of suc... 详细信息

关键词： impulsive differential equation periodic orbit stable

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, shandong normal university,{2., china 2. department 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

A Hybrid of Theorems of Goldbach and Piatetski-Shapiro

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Chinese Annals of Mathematics,Series B 2006年第3期27卷 341-352页

作者： Xianmeng MENG Mingqiang WANG School of Computer Science and Technology, shandong university, {2. 2.0100, china department of Statistics and Mathematics, shandong Finance Institute, jinan 2.0014, china. School of Computer Science and Technology, shandong university, {2. 2.0100, china department of Mathematics, Qufu normal university, Qufu 2.3165, shandong, china. School of Computer Science and Technology Shandong University Jinan 250100 China department of Statistics and Mathematics Shandong Finance Institute Jinan 250014 China department of Mathematics Qufu Normal University Qufu 273165 Shandong China

It is proved that for almost all sufficiently large even integers n, the prime variable equation n = p1 ＋ p2. p1 ∈ Pγ is solvable, with 13/15 〈γ≤ 1, where Pγ = {p ｜p = [m^1/γ], for integer m and prime p} is t... 详细信息

关键词： Circle method Sieve method Goldbach problem

Particle tunnels across the horizon of Garfinkle-Horowitz-Strominger dilaton black hole

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Science china(physics,Mechanics & Astronomy) 2007年第5期50卷 601-610页

作者： FANG HengZhong1 & ZHAO Zheng2.1 department of physics,{2. university of Petroleum, Dongying 2.7061,{2. 2.department of physics, Beijing normal university, Beijing 100875,{2. department of physics China University of Petroleum Dongying 257061 China department of physics Beijing Normal University Beijing 100875 China

We promote the work of Parikh and Wilczek on the black hole radiation to the emission of massive and charged particles from Garfinkle-Horowitz-Strominger black hole. The energy and charge of the space-time are conservational during the course of the evaporation. The calculation shows that the emission spectrum is not precisely thermal, while has a correction, and the conclusion supports the view- point of information conservation.

关键词： Hawking radiation, black body spectrum, barrier, information loss, entropy of black hole, Komar energy

The incorporation of C_(60) in cavities of 5,10,15,2.-tetra-4-oxy(2.stearic acid)phenyl porphyrin in LB film

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Chinese Journal of Chemistry 1995年第5期13卷 415-422页

作者： LIU, Hong-Guo FENG, Xu-Sheng YANG, Kong-ZhangInstitute of Colloid and Interface Chemistry, shandong university, {2., shandong 2.0100, chinaCHENG, Chuan-Fu LI, Jian department of physics, shandong normal university, {2., shandong 2.0014, chinaLIANG, Wei-Andepartment of Chemistry, shandong university, {2., shandong 2.0100, china department of Chemistry Shandong University Jinan Shandong 250100 China

The structure and properties of mixed monolayer or LB film of 5,10,15,2.-tetra-4-oxy(2.stearic acid)phenyl porphyrin/C60 were studied. A isotherms and small angle X-ray diffraction (SAXD) results show that C60 molecules were incorporated into the cavities of por-phyrin molecules in mixed monolayer and LB film . UV-vis spectra of mixed LB films show that the absorption intensity of porphyrin varied compared with pure porphyrin film, probably arising from the interactions between C60 and porphyrin ring. C60 molecules in mixed systems are well-dispersed. The TPP(CO2.)/C60 mixed LB film is a kind of two-dimensional host-guest system.

关键词： C60 LB film porphyrin

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 Feng1,2.1department of Mathematics,Qufu normal {2.,Qufu 2.3165,china 2.chool of Mathematics,shandong {2.,jinan 2.0100,china 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

Transparent Conducting ZnO:Al Films on Different Organic Substrates Deposited by r.f. Sputtering

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Journal of Materials Science & Technology 2000年第1期16卷 23-26页

作者： Yuan CHEN, Deheng ZHANG and Qingpo WANG (department of physics, {2. university, jinan 2.0100, china) Jin MA and Tianlin YANG (Institute of Optoelectronic Materials and Devices, {2. university, jinan 2.0100, china) department of physics Shandong University Jinan 250100 China Institute of Optoelectronic Materials and Devices Shandong University Jinan 250100 China

Transparent conducting ZnO:AI films with good adhesion, low resistivity and high transmittance have been prepared on polyptopylene adipate (PPA), polyisocyanate (PI) and polyester substrates by r.f. magnetron sputtering. The structural, electrical and optical properties of the obtained films were studied. The polycrystalline ZnO:AI films with resistivity as low as 5.76xl0^-4 Ω.cm, carrier concentration 9.06xl0^2. cm^-3 and Hall mobility 11.98 cm^2.V^-1s^-1 were produced on PPA substrate by controlling the deposition parameters. The average transmittance of films on PPA is ～80% in the wavelength range of visible spectrum. The films on PPA substrates have better electrical and optical properties compared with the films on other kinds of substrates.

关键词： ZnO Sputtering Transparent Conducting ZnO Al

Fabrication of hexagonal gallium nitride films on silicon (111) substrates

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Rare Metals 2003年第3期22卷 221-225页

作者： YANGLi XUEChengshan WANGCuimei LIHuaixiang RENYuwen ChemistryFunctionMaterialsLab InstituteofSemiconductorsShandongNormalUniversityJinan250014China physicsDe0artment ShandongNormalUniversityJinan250014China InspectionInstituteforElectronicProductsofshandong Jinan250000China

Hexagonal gallium nitride films were successfully fabricated throughammoniating Ga_2._3 films deposited on silicon (111) substrates by electrophoresis. The structure,composition, and surface morphology of the formed films were characterized by X-ray diffraction(XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), and transmissionelectron microscopy (TEM). The measurement results reveal that the polycrystalline GaN films withhexagonal wurtzite structure were successfully grown on the silicon (111) substrates. Preliminaryresults suggest that varying the ammoniating temperature has obvious effect on the quality of theGaN films formed with this method.

关键词： semiconductor materials GaN films electrophoresis Ga_2._3