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971.
972.
绝缘层LiF/Al电极对提高P-PPV发光器件发光性能的研究 总被引:1,自引:0,他引:1
为了提高聚合物电致发光器件中Ba(Ca)/Al阴极的稳定性,在该阴极与聚合物发光材料poly(2-(4-ethylexyl)phenyl-1,4-phenylene vinylene)(P-PPV)层之间插入一层7nm的LiF绝缘层,发光器件的发光性能在多项参数(发光器件的电压.电流特性、发光强度及外量子效率,以及电流效率等发光性能指标)上能够与工作性能优良但稳定性较差的Ba(Ca)/Al电极结构PLEDs器件的发光特性具有可比性。这对于研制高效率、高稳定的聚合物电致发光器件并最终将其用于商业目的,具有重大现实意义。 相似文献
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977.
载能团簇离子进入固体时, 由于集体相互作用,在入射路径上产生非常高的能量沉积密度。 实验发现, 载能团簇离子的作用结果并不等于团簇中各原子独立作用的总和, 而是具有非线性效应。 就二次离子发射而言, 这种非线性通常与团簇的能量、 团簇的大小、 离子的电荷态以及靶物质的结构有关。 通过研究二次离子发射有助于理解载能团簇离子与物质相互作用过程中的能量沉积与释放机制。 Using energetic cluster as projectile is a unique way to produce simultaneous impacts of several atoms and deposit extremely high energy density in a very small area. The cluster impingement on solids has exhibited some non linear effects not presented in collisions of individual atoms with those solids. The study of the secondary ion emissions can give insight into the energy deposition and relaxation steps of the cluster solid interaction. The dependence of the yields of secondary ion emission induced by clusters on the energy of clusters,cluster sizes,charge states and material structures of the targets was reviewed in this paper. 相似文献
978.
The finite temperature properties of self-assembled dipole chains of polar molecules in strongly confined pancake traps are investigated. The single-chain vibrations at finite temperature, which become important for long chains in a strongly interacting regime, are found to lower the transition temperature and to shift the chain distribution by less than 10%. We also propose experimental parameters to observe such quantum phase transition. 相似文献
979.
Asymptotic Analysis of Vertical Branch-Cut Integral of Shear Waves in a Fluid-Filled Borehole Utilizing the Steepest-Descent Method 下载免费PDF全文
We obtain an asymptotic solution to the vertical branch-cut integral of shear waves excited by an impulsive pressure point source in a fluid-filled borehole, by taking the effect of the infinite singularity of the Hankel functions related to shear waves in the integrand at the shear branch point into account and using the method of steepest-descent to expand the vertical branch-cut integral of shear waves. It is theoretically proven that the saddle point of the integrand is located at ks-i/z, where ks and z are the shear branch point and the offset. The continuous and smooth amplitude spectra and the resonant peaks of shear waves are numerically calculated from the asymptotic solution. These asymptotic results are generally in agreement with the numerical integral results. It is also found by the comparison and analysis of two results that the resonant factor and the effect of the normal and leaking mode poles around the shear branch point lead to the two-peak characteristics of the amplitude spectra of shear waves in the resonant peak zones from the numerical integral calculations. 相似文献
980.
Guiding Neutral Atoms with Two Current-Carrying Wires and a Vertical Bias Field on the Atom Chip 总被引:1,自引:0,他引:1 下载免费PDF全文
We demonstrate the guiding of neutral atoms with two parallel microfabricated current-carrying wires on the atom chip and a vertical magnetic bias field. The atoms are guided along a magnetic field minimum parallel to the current-carrying wires and confined in the other two directions. We describe in detail how the precooled atoms are efficiently loaded into the two-wire guide. We present a detailed experimental study of the motional properties of the atoms in the guide and the relationship between the location of the guide and the vertical bias field. This two-wire guide with vertical bias field can be used to realize large area atom interferometer. 相似文献