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121.
在KT-5C托卡马克上,采用多块组合的可偏压限制器控制等离子体边缘电场.进行了改善等离子体的边缘参数及其机制的研究.实验显示,限制器的正、负偏压都能改变等离子体电位,但正偏压更有效,能有效地建立边缘电场,进而抑制边缘扰动改善等离子体约束.利用可移动静电探针,测得正偏压期间边缘电子温度T_e(r)、电子密度n_e(r)、空间电位V_p(r)分布变陡,与计算得到的边缘粒子通量Г(a_(?))减少,整体粒子约束时间τ_p增加结果是一致的. 相似文献
122.
123.
Dynamics of vibrational chaos and entanglement in triatomic molecules: Lie algebraic model 下载免费PDF全文
In this paper, the dynamics of chaos and the entanglement in triatomic molecular vibrations are investigated. On the classical aspect, we study the chaotic trajectories in the phase space. We employ the linear entropy to examine the dynamical entanglement of the two bonds on the quantum aspect. The correspondence between the classical chaos and the quantum dynamical entanglement is also investigated. As an example, we apply our algebraic model to molecule H2O. 相似文献
124.
The effect of Rashba spin-orbit coupling (SOC) on electron transport in asymmetrically coupled regular polygonal quantum ring is investigated. In absence of SOC, two kinds of conductance zeros appear periodically. In presence of SOC, one kind of conductance zero can be lifted by the Rashba SOC, the others persist. 相似文献
125.
采用2维三温非平衡辐射流体力学程序LARED-H数值模拟辐射驱动内爆过程。针对2维三温能量方程九点差分格式离散后的线性方程组,采用了高效的Krysolv子空间迭代解法,改进了代数解法器。将1维间接驱动内爆总体程序CFJ与LARED-H程序的计算结果进行比对,验证了LARED-H程序数值模拟1维内爆问题的正确性。并数值模拟了不同腔长辐射温度源驱动下的2维靶球运动,数值结果显示:随着腔长的增加,高压缩内爆燃料区分别被压缩成香肠形、球形和铁饼形,数值模拟结果与神光Ⅱ的实验结果定性上相同。 相似文献
126.
(Pb0.5Ba0.5)ZrO3 (PBZ) and 1 mol% Mn-doped (Pb0.5Ba0.5)ZrO3 (Mn-PBZ) sol were successfully fabricated, and corresponding thin films were deposited on Pt(1 1 1)/TiO2/SiO2/Si(1 0 0) substrates by spin-coating method. Effects of Mn doping on the microstructure and electrical properties of PBZ thin films were investigated systemically. X-ray diffraction patterns showed that both films had a polycrystalline perovskite structure, and that the degree of (1 1 1) orientation were increased by Mn doping. Dielectric measurements illustrated that Mn-doped PBZ thin films not only had a larger dielectric constant, but also possessed a smaller dielectric loss. Accordingly, the tunability and the figure of merit of PBZ films were improved by Mn doping. 相似文献
127.
128.
在当今社会,噪声污染已经成为人类健康的一大威胁,如何有效地控制和消除噪声污染一直是科研领域的一个重要话题.本文以开口环嵌套结构为模型,设计并制备了一种声学超材料.通过理论分析、数值模拟和实验测试,发现由于模型内部空腔的强烈耦合共振效应,该超材料可以在低频区域实现接近完美的吸声效应.此外,通过简单地绕轴旋转其内腔开口方向,即可改变该超材料的相对阻抗值,进而在较宽的频带范围内实现对吸收峰位置的可调控制.由于该超材料具有深亚波长的尺寸,因此非常有利于低频吸声器件的小型化和集成化,同时该模型也为宽带吸收器的设计奠定了基础. 相似文献
129.
Peng-Wang Zhai Yongxiang Hu Jacek Chowdhary Charles R. Trepte Patricia L. Lucker Damien B. Josset 《Journal of Quantitative Spectroscopy & Radiative Transfer》2010,111(7-8):1025-1040
We report on an exact vector (polarized) radiative transfer (VRT) model for coupled atmosphere and ocean systems. This VRT model is based on the successive order of scattering (SOS) method, which virtually takes all the multiple scattering processes into account, including atmospheric scattering, oceanic scattering, reflection and transmission through the rough ocean surface. The isotropic Cox–Munk wave model is used to derive the ref and transmission matrices for the rough ocean surface. Shadowing effects are included by the shadowing function. We validated the SOS results by comparing them with those calculated by two independent codes based on the doubling/adding and Monte Carlo methods. Two error analyses related to the ocean color remote sensing are performed in the coupled atmosphere and ocean systems. One is the scalar error caused by ignoring the polarization in the whole system. The other is the error introduced by ignoring the polarization of the light transmitted through the ocean interface. Both errors are significant for the cases studied. This code fits for the next generation of ocean color study because it converges fast for absorbing medium as, for instance, ocean. 相似文献
130.
Based on the experimental device which is a non-uniform magnetic field to trap an atom, we show how to obtain a certain velocity of a Bose gas by controlling the magnetic coils. By comparing the relationship of the different current supply and delay time versus the ultimate velocity of the atom, we theoretically predict the method of accelerating the gases to an expected velocity. This method is of great convenience and significance for the applications in cold atom physics and precision measurements. 相似文献