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141.
FAN CuiLing LEI JianGuo & SHAN XiuLing School of Sciences Nantong University Nantong China College of Mathematics Information Science Hebei Normal University Shijiazhuang 《中国科学 数学(英文版)》2011,(1)
Difference systems of sets (DSSs) are combinatorial configurations which were introduced in 1971 by Levenstein for the construction of codes for synchronization. In this paper, we present two kinds of constructions of difference systems of sets by using disjoint difference families and a special type of difference sets, respectively. As a consequence, new infinite classes of optimal DSSs are obtained. 相似文献
142.
CHEN ShengBo & SONG JinHong College of Geoexploration Science Technology Jilin University Changchun China College of Resources Environment Jilin Agricultural University Changchun 《中国科学:物理学 力学 天文学(英文版)》2011,(8)
Atmospheric temperature-humidity profiles and land or sea surface temperature are coupled actions in the earth system process. Based on the numerical perturbation form of the atmospheric radiative transfer equation, a physics-based algorithm is pre- sented to integrate four pairs of MODIS measurements from the Terra and Aqua satellites to retrieve simultaneously atmospheric temperature-humidity profile, land-surface temperature and emissivity. Three pairs of MODIS data at two field sites in China, Luancheng... 相似文献
143.
LONG LiuRong LI HongWei ZHOU Ping FAN Chao & YIN CaiLiu College of Physics Electronic Engineering Guangxi University for Nationalities Nanning China 《中国科学:物理学 力学 天文学(英文版)》2011,(3)
We present a scheme for multiparty-controlled teleportation of an arbitrary high-dimensional GHZ-class state with a d-dimensional (N+2)-particle GHZ state following some ideas from the teleportation (Chinese Physics B, 2007, 16: 2867). This scheme has the advantage of transmitting much fewer particles for controlled teleportation of an arbitrary multiparticle GHZ-class state. Moreover,we discuss the application of this scheme by using a nonmaximally entangled state as its quantum channel. 相似文献
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We create a GaN photocathode based on graded Alx Ga1-x N buffer layers to overcome the influence of buffer-emission layer interface on the photoemission of transmission-mode GaN photocathodes.A gateshaped spectral response with a 260-nm starting wavelength and a 375-nm cut-off wavelength is obtained.Average quantum efficiency is 15% and short wavelength responses are almost equivalent to long wavelength ones.The fitted interface recombination velocity is 5×104 cm/s,with negligible magnitude,proving that the design of the graded buffer layers is efficient in obtaining good interface quality between the buffer and the emission layer. 相似文献
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利用密度泛函理论和弹性散射格林函数方法,对硫醇分子膜的电学特性进行了理论模拟,计算结果表明,分子结的导电能力随着压力增加而增加,对单分子构成的分子结来说,电流的增加主要是由于电极距离的变化导致单个分子与电极的耦合增强,对于由多个分子构成的分子膜来说,由于外加压力的变化,导致分子结的链内隧穿和链间隧穿几率增大,从而导致导... 相似文献
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In the framework of the relativistic mean field theory, the effects of the δ meson on the direct Urca (DURCA) processes are investigated. In a neutron star, the DURCA processes involving nucleons, Λ and Ξ- can take place while the process involving the Ξ0 can not. With the inclusion of the δ meson, the threshold densities for the DURCA processes become lower. With the δ included, the threshold neutron star mass for the DURCA process among nucleons and electrons becomes smaller while the threshold masses for the processes involving hyperons become larger. When the δ meson is included, the total neutrino emissivity remarkably increases in the density range of 0.32--0.41 fm-3. The total neutrino luminosity increases with the neutron star mass first and then decreases. The neutrino luminosity gets larger with the inclusion of the δ meson. The cooling of the EXO0748-676 is sensitive to the isovector scalar interaction. 相似文献