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Study on sea water intrusion into palaeochannels on south coastal plain of the Laizhou Bay by the Bohai Sea

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Acta Oceanologica Sinica 2003年第1期22卷 69-74页

作者： Han Mei Geography Department, shandong normal university, jinan 250014, china shandong normal Univ Dept Geog Jinan 250014 Peoples R China

The palaeochannel evolution in the study region is divided into four stages by such methods as 14C dating. Sea water intrusion through palaeochannels has been studied as a focal point. Palaeochannels are the main passageways through which the sea water intrudes at a higher speed, through many means and in a changeable dynamic state.

关键词： Palaeochannel sea water intrusion south coastal plain of Laizhou Bay

A note on a result of Abercrombie

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Chinese Science Bulletin 1997年第14期42卷 1151-1154页

作者： ZHAI WenguangDepartment of Mathematics, shandong normal university, jinan 250014, china Department of Mathematics Shandong Normal University Jinan 250014 China

SUPPOSE θ∈[1,+ ∞) is any real number. The sequence B_θ={[nθ]|n∈N}is calledBeatty’s sequence determined by θ. Beatty sequences have been the subject of intensive inves-tigation in recent years on account of the... 详细信息

关键词： Bealty’s sequence divisor problem rational approximation.

Reciprocal sums of a class of additive functions in short intervals

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Chinese Science Bulletin 1997年第2期42卷 102-105页

作者： ZHAI WenguangDepartment of Mathematics, shandong normal university, jinan 250014, china Department of Mathematics Shandong Normal University Jinan China

USING the method of probabilistic number-theory, De Koninck, and De Koninck and Galambos studied the reciprocal sum of the additive function f（n） satisfying f（n）≥t0>0 （n≥2） and f（p）≡1 and obtained an asymptotic formula, where t0 is an absolute positive constant. Let B（x） denote the number of n≤x not satisfying the inequality loglogn-R（x）≤f（n）≤loglogn+R（x）, （1） where R（x） is a function tending to infinity. Then in refs. [1, 2], it is proved that if R（x）=o（loglogx） and B（x）=o（x/loglogx）,

关键词： additive functions Riemann zeta-function asymptotic formula.

The Ambient Gas Effects on Pulsed Laser Ablation of Target

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光电子·激光 1996年第1期7卷 12-15页

作者： Gongtang Wang Xiangtai Wang Baoyuan Mian(Department of physics,shandong normal university,jinan 250014)Bingzhang Xu Liangmo Mei(Department of physics.shandong university,jinan 250100) 山东师范大学物理系山东济南山东大学物理系山东济南

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ＴｈｅＡｍｂｉｅｎｔＧａｓＥｆｆｅｃｔｓｏｎＰｕｌｓｅｄＬａｓｅｒＡｂｌａｔｉｏｎｏｆＴａｒｇｅｔ￥ＧｏｎｇｔａｎｇＷａｎｇ；ＸｉａｎｇｔａｉＷａｎｇ；ＢａｏｙｕａｎＭｉａｎ（Ｄｅｐａｒｔｍｅｎｔｏｆｐｈｙｓｉｃｓ，ＳｈａｎｄｏｎｇＮｏｒｍａｌＵｎｉ...

关键词： Al￣+ ion mean projected range laser ablation ambient gas effect.

On the error term in Weyl’s law for the Heisenberg manifolds (Ⅱ)

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Science china Mathematics 2009年第5期52卷 857-874页

作者： ZHAI WenGuang School of Mathematical Sciences, shandong normal university, jinan 250014, china 1. School of Mathematical Sciences Shandong Normal University Jinan 250014 China

In this paper we study the mean square of the error term in the Weyl's law of an irrational (2l + 1)-dimensional Heisenberg manifold. An asymptotic formula is established.

关键词： Heisenberg manifold Weyl’s law error term mean square

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 Shenglu2 1. School of physics and Electronic Engineering, Yantai normal university, Yantai 264025, china 2. Department of physics, shandong normal university, jinan 250014, 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 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, jinan 250014, 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

Optical waveguides in LiNbO_3 and stoichiometric LiNbO_3 crystals by proton exchange

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Science china(physics,Mechanics & Astronomy) 2008年第10期51卷 1479-1488页

作者： LI ShiLing College of physics and Engineering, Qufu normal university, Qufu 273165, china School of physics and Microelectronics, shandong university, jinan 250100, china 1. College of physics and Engineering Qufu Normal University Qufu 273165 China 2. School of physics and Microelectronics Shandong University Jinan 250100 China

The formation of optical planar waveguides in LiNbO3 and stoichiometric LiNbO3 crystals by proton exchange was reported. The prism-coupling method was used to characterize the dark-line spectroscopy at the wavelength of 633 and 1539 nm, re-spectively. The mode optical near-field outputs from proton-exchanged LiNbO3 and SLN waveguides at 633 nm were presented. The mode field from stoichiometric LiNbO3 (SLN) waveguide is lighter and more uniform than that from LiNbO3 waveguide, which means the quality of the waveguide in SLN crystal is better than that of the LiNbO3 waveguide. For proton-exchanged LiNbO3 waveguides, the evo-lution of the refractive index profile with annealing was presented. The disorder profiles of Nb atoms in proton-exchanged LiNbO3 waveguides were obtained by Rutherford backscattering/channeling technique. It is shown that the longer the exchange time, the larger the displacement of Nb atoms.

关键词： optical waveguide proton exchange LiNbO3 crystal stoichiometric LiNbO3 crystal

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_2O_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_2O_3