Electrochromic properties of nano-composite nickel oxide film

In this study, we develop a nano-composite nickel oxide (NNO) film on the indium tin oxide (ITO)-coated glass substrate for electrochromic applications. The NNO film is composed of the core-shell structure of NiO/conducting ITO nano-particles. High porosity in the NNO film offers large active surface area for redox reaction. Electrochromic electrodes fabricated with the NNO films produce high transmittance variation (66.2% at a wavelength of 550 nm), fast switching speed (coloring: 3.5 s; bleaching: 4 s) and good durability, which are much better than those of ones made with the traditional nickel oxide films. The structure, morphology, and electrochromic properties are characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS) and UV-vis spectroscopy.     

Investigation on Rijke pipe＇s acoustic characteristics by numerical simulation： modeling the pulsing flow field coupled the inner of pipe with its outer space

Based on the results of fluid dynamics, heat transfer and acoustics, a Computational Fluid Dynamics （CFD） method was utilized to study the acoustic characteristics and self-excited pulsation mechanism inside a Rijke pipe. To avoid settling the irrational boundary conditions of the finite-amplitude standing wave in the Rijke thermo-acoustic system, the simulation modeling in the flow field, which coupled the inner of pipe with its outer space, was carried out to replace the traditional way in form of internal flow field numerical investigations. A hypothesis for heat source in energy equation including the relationship on unsteady heat of air around heat source, oscillation pressure and oscillation velocity was presented. To reflect the essence of Rijke pipe, simulation on self-excited oscillation was conducted by means of its own pulsation of pressure, velocity and temperature. This method can make the convergence process steady and effectively avoid divergence. The physical phenomenon of the self-excited Rijke pipe was analyzed. Moreover, the mechanisms on the Rijke pipe＇s self-excited oscillation were explained. Based on this method, comparative researches on the acoustic characteristic of the Rijke pipe with different size and different shape of nozzle were performed. The simulation results agreed with the experimental data satisfactorily. The results show that this numerical simulation can be used to study the sound pressure of nozzle for the engineering application of Rijke pipes.     

Hawking Radiation from Topological Kerr Anti-de-Sitter Black Hole with One Rotational Parameter via Covariant Anomalies

Using anomalous viewpoint, we study the Hawking radiation from a kind of topological Kerr Anti-de-Sitter （Kerr-AdS） black hole with one rotational parameter. We employ the covariant gauge and gravitational anomalies. The result supports the Robinson-Wilczek opinion and shows that the Hawking temperature can be correctly determined by cancelling covariant gauge and gravitational anomalies at the horizon.     

纳米团簇B92的密度泛函理论研究

利用密度泛函理论(DFT)研究了一种新颖的准球形纳米团簇B92.经过结构优化和频率分析,这一准球形笼状团簇的直径为0.968 nm,其结构满足Eoustani提出的"Aufbau principle".团簇B92的平均结合能、能隙(HOMO-LUMO gap)、垂直电离势(VIP)及垂直电子亲和势(VEA)分别为5.28 eV,1.19 eV,5.47eV及2.45 eV.计算所得到的红外谱(IR)上有一个明显的峰在895 Cm-1处.此谱将有助于从实验上确定本文所提出的团簇B92的结构,团簇B92的电荷分布表明,其有望成为未来纳米电子学中的一种电容器,另外,作为比较,本文也给出了其他一些笼状硼团簇的性质.     

一维自旋-1/2XY模型的磁场效应

本文主要利用Haldane的谐振流理论——玻色化方法研究外场中的自旋-1/2XY模型。本文首先将无磁场情况下该模型的哈密顿进行了玻色化与对角化,并单独讨论了磁场项,最后两者联合给出外磁场中一维自旋-1/2模型哈密顿的玻色化形式。在这种形式下哈密顿量中的协变问题可以通过平移费米点来解决,所以,在阿贝尔玻色化方案下对玻色场算符做了重新定义,得到一个新的协变的哈密顿,从而解决了由于扰动所带来的问题,各关联函数也随之给出;最后简单讨论了平移费米点给模型关联函数的表达式带来的变化,以及玻色化方法较之其他方法的优长。     

混沌振子系统周期解几何特征量分析与微弱周期信号的定量检测

提出了一种对微弱周期信号的定量检测方法.分析混沌振子系统在大尺度周期状态下的相对稳定输出时,发现了混沌振子系统输出周期解的平均面积是一个比较稳定的几何特征量.该几何特征量与待测信号幅值之间存在比较稳定的单调递增关系.在一定的参数条件下,几何特征量精度可达到10^-6V².利用混沌系统对随机噪声信号的免疫性和对微弱周期信号的敏感性,进一步建立了微弱周期信号的定量检测方法.仿真实验表明,随着待检测幅度的增加,在保证检测精度的同时,抗噪性能也随之增强. 关键词： 混沌振子系统 大尺度周期相态 周期解的几何特征量 微弱周期信号的定量检测     

金纳米颗粒的有序制备及其光学特性

采用纳米球蚀刻技术在石英衬底上制备了不同高度的金纳米颗粒阵列.通过扫描电子显微镜对其表面形貌进行了观测,表明金纳米颗粒为有序分布的三棱柱结构.通过红外—紫外吸收光谱仪在190—900nm波长范围内对其光吸收特性进行了测量, 并成功观测到了金纳米颗粒表面等离子体振荡效应引起的光吸收峰,结果表明随着金纳米颗粒高度的增加,其吸收峰的位置向短波方向移动(蓝移).同时对金纳米颗粒的光吸收特性进行了基于离散偶极子近似的理论计算,并与实验结果进行了比较. 关键词： 纳米球蚀刻技术 金纳米颗粒 离散偶极子近似     

基于TE-TM模变换的新型相位自补偿磁光隔离器

讨论了由45°非互易模变换器与45°互易模变换器构成波导型光隔离器时两者之间须满足的条件,并由此设计了一种新型的相位自补偿磁光隔离器. 利用全矢量有限差分光束传输法对隔离器进行仿真,得到了插入损耗为-12dB,隔离度为-34dB的结果. 关键词： 集成光学 磁光隔离器 非互易模变换器 互易模变换器     

Nambu力学系统的Lie对称性及其守恒量

讨论了Nambu力学系统的Lie对称性;建立了系统Lie对称性的确定方程;得到了该对称性引起的守恒量;研究了Lie对称性逆问题. 并以Euler方程为例说明了本文的主要结果. 关键词： Nambu力学系统 Lie对称性 守恒量     

2D NMR对金钱松皮中的一个三萜皂苷进行结构解析

通过核磁共振谱并结合文献对一个三萜皂苷dammar-24(25)-ene-3β, 6α, 12β, 20 (S)-tetraol-20-O-β-D- pyranoglucoside 进行结构解析. 通过2D NMR(1H-1H COSY、HMQC、HMBC)对其进行了NMR全归属.