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111.
112.
A separated pair calculation of the electronic structure of the Li2O molecule is described. Rather extensive calculations were made of the potential surface for symmetric configurations of Li2O using a double zeta Slater orbital basis. A linear configuration with LiO bond length of 1.71 Å is found to be most stable. The electron distribution and correlation effects are discussed. 相似文献
113.
TENG Honghui & JIANG Zonglin . Key Laboratory of High Temperature Gas Dynamics Institute of Mechanics Chinese Academy of Sci- ences Beijing China . Graduate University of Chinese Academy of Sciences Beijing China 《中国科学G辑(英文版)》2005,48(6):739-749
Shock wave focusing is a fundamental problem in the shock wave research and the instantaneous impulse of high temperature and pressure generated at the focal points has been applied recently in industrial and medical researches[1]. There are several methods to create shock wave focusing, among which the more commonly-used one is to make a planar shock wave reflect from a concave surface, such as the elliptical or parabolic re- flector. Toroidal shock wave focusing has been proposed and investi… 相似文献
114.
Back BB Baker MD Ballintijn M Barton DS Becker B Betts RR Bickley AA Bindel R Budzanowski A Busza W Carroll A Decowski MP García E Gburek T George N Gulbrandsen K Gushue S Halliwell C Hamblen J Harrington AS Henderson C Hofman DJ Hollis RS Hołyński R Holzman B Iordanova A Johnson E Kane JL Khan N Kulinich P Kuo CM Lee JW Lin WT Manly S Mignerey AC Noell A Nouicer R Olszewski A Pak R Park IC Pernegger H Reed C Remsberg LP Roland C Roland G Sagerer J Sarin P Sawicki P Sedykh I Skulski W Smith CE 《Physical review letters》2003,91(7):072302
We have measured transverse momentum distributions of charged hadrons produced in d+Au collisions at sqrt[s(NN)]=200 GeV. The spectra were obtained for transverse momenta 0.25
相似文献
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运用密度泛函理论体系下的平面波赝势(PWP)和广义梯度近似(GGA)方法,计算研究了闪锌矿结构的ZnS晶体在不同的外界压强下的电子结构. 通过分析发现,随着外界压强的增大,晶格常数和键长在不断缩小,从S原子向Zn原子转移的电荷越来越少,Zn—S键的共价性逐渐增强,Zn原子和S原子的态密度都有不同程度的变化,而且还有向低能量移动的趋势. 当外界压强达到24GPA时,ZnS从直接带隙半导体变成间接带隙半导体,而且随着压强的增大,间接带隙逐渐变小,直接带隙逐渐增大.
关键词:
闪锌矿结构
态密度
能带结构
密度泛函理论 相似文献
118.
C. Feng B.H. Li G. Han J. Teng T. Yang Y. Jiang G.H. Yu 《Applied Physics A: Materials Science & Processing》2007,87(1):121-124
We have studied the effect of a Bi underlayer on ordering and coercivity Hc of FexPt100-x thin films (atomic content of Fe x=40∼58). We found that the Bi underlayer enhances Hc remarkably. After annealing at 400 °C for 20 min, a Bi/Fe49Pt51 film can realize an Hc as high as 1.07×103 kA/m and a ratio of the remnant Mr to the saturated magnetization Ms as high as 0.93. The ordering process of FePt film was promoted by the diffusion of Bi atoms. Moreover, the Bi underlayer
broadens the range of x for high Hc from 49∼55 to 43∼55. Interestingly, with Bi underlayer, the high Hc is affected by x to a less extent.
PACS 75.50.Ss; 75.50.Vv; 75.60.Ej 相似文献
119.
L. Qian Z. Xu F. Teng X.-X. Duan Z.-S. Jin Z.-L. Du F.-S. Li M.-J. Zheng Y.-S. Wang 《Journal of nanoparticle research》2007,9(3):523-527
Efficiency of polymer light-emitting diodes (PLEDs) with poly(2-methoxy-5-(2-ethyl hexyloxy)-p-phenylene vinylene) (MEH-PPV) as an emitting layer was improved if a dehydrated nanotubed titanic acid (DNTA) doped hole-buffer
layer polyethylene dioxythiophene (PEDOT) was used. Photoluminescence (PL) and Raman spectra indicated a stronger interaction
between DNTA and sulfur atom in thiophene of PEDOT, which suppresses the chemical interaction between vinylene of MEH-PPV
and thiophene of PEDOT. The interaction decreases the defect states in an interface region to result in enhancement in device
efficiency, even though the hole transporting ability of PEDOT was decreased. 相似文献
120.
We study the Fresnel diffraction of Gaussian beam truncated by one circular aperture, and give the general analytic expression of the Fresnel diffraction of truncated Gaussian beam denoted by Bessel functions. Then the characteristic of the axial diffraction fluctuation and the influence of the caliber of the circular aperture and the wave waist of Gaussian beam on the diffraction distributions are discussed, respectively. Through the numerical calculations, the characteristics of the transverse diffraction are presented and the relationship of the fluctuation of the transverse diffraction profile and the position of the axial point is shown. The physical origin of the fluctuation of Fresnel diffraction intensities of truncated Gaussian beam is expressed in terms of Fresnel half-zone theory. These phenomena and the conclusions are important for the measurement of the parameters of the beam and its applications. 相似文献