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121.
In this review, we introduce the operating principle of photoinduced force microscopy (PiFM) and its applications. First, we introduce that the photoinduced force includes the gradient force and the scattering force. Next, we explain how to eliminate the effects of photothermal effects on the metal tip and sample surface caused by light irradiation. Then, we introduce a PiFM operating in air based on the tapping mode and present images of SiNc clusters. Furthermore, we introduce a PiFM operating in vacuum based on the frequency modulation (FM) mode, and present the results of three-dimensional photo-induced force vector measurements of semiconductor quantum dots. 相似文献
122.
通过Raman散射声子谱研究了Pr掺杂对Bi2212体系顶点氧振动频率的影响,发现掺杂导致振动频率向低频方向移动.分析表明体系中BiO双层收缩是导致声子发生软化的主要原因.结合体系的结构特征,从能量关系角度上讨论了BiO双层随掺杂发生收缩的原因. 相似文献
123.
Falin Liu Weidong Wang Lingyun Zhou Qingguo He 《International Journal of Infrared and Millimeter Waves》2003,24(9):1531-1538
Based on a miniaturized NRD-guide coupling structure, a new switch circuit is proposed. The 3dB coupler and two schottky barrier diodes with improved diode mounts and matching circuits are used. It features with wideband performance and compact size. The high isolation performance can also be realized using the same circuit by adjusting the bias currents of the diodes. An experimental prototype is implemented and the tested characteristics are supplied. 相似文献
124.
In this paper, we give the necessary and sufficient conditions for the boundedness of fractional integral operators on the modulation spaces. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
125.
Time resolved spectral interferometry is applied to femtosecond pulse coherent measurement. A new configuration that can be directly applied to single shot detection is presented. The efficiency of this self-referenced real-time passive technique is experimentally demonstrated during the characterization of chirped pulses. Additionally, we quantitatively retrieve the spectral phase shift which is associated to the propagation through a F4 glass parallel plate. Numerical results are also reported showing examples of complex pulse characterization. Finally, limitations of the technique are discussed. 相似文献
126.
本文使用DC-PBH型激光二极管芯片,设计制作了实用化封装形式的激光器组件;在理论上和实验上研究了组件的封装模型和小信号频率调制特性,其光响应3dB带宽大于1.8GHz。该器件可满足六次群的光通信系统的带宽要求,也可用于GHz级的微波副载波光通信系统。 相似文献
127.
This paper studies spectral density estimation based on amplitude modulation including missing data as a specific case. A
generalized periodogram is introduced and smoothed to give a consistent estimator of the spectral density by running local
linear regression smoother. We explore the asymptotic properties of the proposed estimator and its application to time series
data with periodic missing. A simple data-driven local bandwidth selection rule is proposed and an algorithm for computing
the spectral density estimate is presented. The effectiveness of the proposed method is demonstrated using simulations. The
application to outlier detection based on leave-one-out diagnostic is also considered. An illustrative example shows that
the proposed diagnostic procedure succeeds in revealing outliers in time series without masking and smearing effects.
Supported by Chinese NSF Grants 10001004 and 39930160, and Fellowship of City University of Hong Kong. 相似文献
128.
通过对仪器的扩展函数的计算、分析,选择出单光栅等效双光栅型SISAM中面光源的最佳尺寸以及调制器的最佳调制幅度。 相似文献
129.
降解裙带菜多糖对纳米硒的形成与稳定作用 总被引:2,自引:0,他引:2
在常温下的降解裙带菜多糖(Degraded Undaria Pinnatifida Charv. Suringer polysaccharide, DUP)水溶液中, 由适当过量的抗坏血酸(Vc)与二氧化硒(SeO2)反应制备纳米单质硒(Se0). 通过共振瑞利散射、激光散射和透射电镜(TEM)研究了DUP对Se0粒径的调控和在液相中的稳定作用. 结果表明, DUP通过控制还原速度和表面修饰而把Se0粒子调节在较窄的粒径分布范围内当Se0浓度为0.0507—3.245 mmol/L时, DUP表面修饰的球状纳米硒的平均粒径稳定地保持在24—65 nm范围内, 4 ℃时可在水溶液中稳定保存1个月. 相似文献
130.