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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 25.014, 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

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

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

Electronic structure and magnetism of compound Nd_2Fe_(17)N_3

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Chinese Science Bulletin 1998年第4期43卷 278-282页

作者： JIANG Tao and LI Hua department of physics, shandong university, jinan 250100, china department of physics Shandong University Jinan 250100 China

The electronic structure and magnetism of compound Nd\-2Fe 17 N\-3 has been studied with MS_Xα method. It was found that there are negative exchange couplings between Fe(f) and Fe(c) atoms in Nd\-2Fe 17 N x compounds. The interstitial N atoms make the unit cell volume of the compounds increase a little, and hence the strength of negative exchange coupling decreases.

关键词： compounds of R\-2Fe 17 type Curie temperature electronic density of states exchange splitting atomic magnetic moment.

STRUCTURE AND MAGNETIC PROPERTIES OF Fe/Pd COMPOSITIONALLY MODULATED FILMS

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Acta Metallurgica Sinica(English Letters) 1993年第8期6卷 112-115页

作者： ZHANG Lin LIU Yihua shandong university,jinan,china WANG Hao Dongnan university,Nanjing,china engineer,department of physics,shandong university,jinan 250100,china shandong Univ Jinan China

Metal Fe/Pd compositionally modulated films(CMFs) were prepared by vapour depo- sition from two sources onto glass substrate under *** modulation and crystal structures of the films were examined by X-ray *** magnetic properties were determined by vibrating sample *** Pd layers in the Fe/Pd CMFs are of fcc structure,and the Fe layer structure transits from bcc into amorphous,state with decreasing thickness of Fe *** dependence of specific saturation magnetization on thickness of Fe layers has also been discussed.

关键词： compositionally modulated films modulated structure specific saturation magnetization

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 university, jinan 250100, china department of physics, Linyi Teachers university, shandong 276005, 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 MgCNi2T (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 MgCNi2Co to +3.02 in MgCNi2Fe. 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

Conduction Properties and Scattering Mechanisms in F-doped Textured Transparent Conducting SnO_2 Films Deposited by APCVD

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Journal of Materials Science & Technology 1997年第1期13卷 50-56页

作者： Deheng ZHANG(Dept. of physics, shandong university, jinan 250100, china)Honglei MA(Institute of Optoelectronic Materials and Devices, shandong university, jinan 250100, china) Dept. of physics Shandong University Jinan 250100 China Institute of Optoelectronic Materials and Devices Shandong University Jinan 250100 China

Transparent conducting F-doped texture SnO2 films with resistivity as low as 5× 10-4 Ω ·cm,with carrier concentrations between 3.5 × 1020 and 7× 1020 cm-3 and Hall mobilities from 15.7 to 20.1 cm2/(V/s) have been prepared by atmosphere pressure chemical vapour deposition (APCVD). These polycrystalline films possess a variable preferred orientation, the polycrystallite sizes and orientations vary with substrate temperature. The substrate temperature and fluorine flow rate dependence of conductivity, Hall mobility and carrier conentration fOr the resultingfilms have been obtained. The temperature dependence of the mobiity and carrier concentrationhave been measured over a temperature range 16～400 K. A systematically theoretical analysis on scattering mechanisms for the highly conductive SnO2 films has been given. Both theoretical analysis and experimental results indicate that for these degenerate, polycrystalline SnO2 ：F films in the low temperature range (below 100 K), ionized impurity scattering is main scattering mechanism. However, when the temperature is higher than 100 K, the lattice vibration scattering becomes dominant. The grain boundary scattering makes a small contribution to limit the mobility of the films.

关键词： SnO cm Conduction Properties and Scattering Mechanisms in F-doped Textured Transparent Conducting SnO2 Films Deposited by APCVD

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 25.014, 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 25.014, 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