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Feng-Bin Liu 《Frontiers of Physics》2016,11(1):116804
To elucidate the effects of physisorbed active ions on the geometries and electronic structures of hydrogenated diamond films, models of HCO−3 , H3O+, and OH− ions physisorbed on hydrogenated diamond (100) surfaces were constructed. Density functional theory was used to calculate the geometries, adsorption energies, and partial density of states. The results showed that the geometries of the hydrogenated diamond (100) surfaces all changed to different degrees after ion adsorption. Among them, the H3O+ ion affected the geometry of the hydrogenated diamond (100) surfaces the most. This is well consistent with the results of the calculated adsorption energies, which indicated that a strong electrostatic attraction occurs between the hydrogenated diamond (100) surface and H3O+ ions. In addition, electrons transfer significantly from the hydrogenated diamond (100) surface to the adsorbed H3O+ ion, which induces a downward shift in the HOMO and LUMO energy levels of the H3O+ ion. However, for active ions like OH− and HCO−3 , no dramatic change appears for the electronic structures of the adsorbed ions. 相似文献
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以Chen系统为研究对象,研究其加入扰动项后的动力学特性。分析了时滞扰动Chen系统的平衡点及其稳定性等问题,计算特征根分布及其对应Hopf分岔特征量。根据Hopf分岔定理判断分岔类型及方向,给出分岔发生的条件并运用Matlab仿真验证了当系统经过临界点时会发生Hopf分岔现象。针对时滞扰动带来的Hopf分岔设计线性控制器并将其添加到系统方程中,对其进行滞后控制,仿真结果表明,该控制器使系统在不改变平衡点的前提下,将分岔临界点由0.1609延迟至0.1860,可对扰动引起的Hopf分岔进行有效控制。 相似文献
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本文采用一种新的测试技术——光热辐射计量术(PTh),对固体材料进行非接触式光谱研究,文中介绍了光热辐射计量理论,并在实验上获得Ce_2O_3粉末和果树叶的相对光谱吸收系数. 相似文献
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超快时间分辨光谱学为研究非线性光学,固体物理,化学反应动力学,能量传递和驰豫、生物过程动力学和相干光谱技术提供了一种有效的工具。本文报导了一种飞秒时间分辨光学多道光谱设备,该设备是由一台用氩离子激光器原浦且产生100fs光脉冲并调谐在720-980nm的飞秒掺钛兰宝石激光器,改进了光学多道器(OMA-II),386计算机及光学系统组成的。激光脉冲用LBO晶体倍频,谱仪装置的时间分辨率约120fs, 相似文献
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离子束溅射沉积Ti-Ni薄膜及其电化学性能的研究 总被引:1,自引:0,他引:1
利用离子束溅射沉积的方法在不同基片温度条件下制备了不同成分的Ti-Ni贮氢薄膜,研究了其电化学贮氢性能。结果表明:用离子束溅射沉积制备的Ti-Ni薄膜的结构为非晶状,薄膜对基片的附着力较强,在冲放电循环50次后仍为非晶态;在基片温度为350℃时制备的薄膜的结构为晶态,在多次放电循环后呈现非晶化趋势;Ti-Ni薄膜具有较高的电化学活性,晶化薄膜比晶态薄膜的最大放电容量高,但晶化薄膜的循环稳定性差。 相似文献
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本文在分析声光可调谐滤光器透过特性的基础上。对其引入了光谱传递函数的概念,并计算和讨论了光谱传递函数随滤光器结构参数的变化规律。 相似文献
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研究了气溶胶对大气偏振分布的影响。基于蒙特卡罗法的矢量辐射传输模式,对不同气溶胶条件下的偏振分布模式进行了仿真。利用图像式测试系统,对实际大气条件的偏振模式进行了测试,分析了气溶胶质量浓度变化对偏振模式的影响。结果表明,偏振度受气溶胶质量浓度的影响较大,随着气溶胶质量浓度的升高,偏振度不断变小。当PM10的质量浓度由27μg/m~3增加到53μg/m~3再增加到103μg/m~3,PM2.5的质量浓度由9μg/m~3增加到28μg/m~3再增加到66μg/m~3时,最大偏振度值平均减小了约25%。气溶胶对偏振方位角几乎没有影响,偏振方位角的分布稳定。 相似文献
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An easy and efficient way to treat Green's function for nano-devices with arbitrary shapes and multi-terminal configurations
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The efficiency of the calculation of Green's function (GF) for nano-devices is very important because the calculation is often needed to be repeated countlessly. We present a set of efficient algorithms for the numerical calculation of GF for devices with arbitrary shapes and multi-terminal configurations. These algorithms can be used to calculate the specified blocks related to the transmission, the diagonals needed by the local density of states calculation, and the full matrix of GF, to meet different calculation levels. In addition, the algorithms for the non-equilibrium occupation and current flow are also given. All these algorithms are described using the basic theory of GF, based on a new partition strategy of the computational area. We apply these algorithms to the tight-binding graphene lattice to manifest their stability and efficiency. We also discuss the physics of the calculation results. 相似文献