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排序方式: 共有983条查询结果,搜索用时 281 毫秒
91.
Zhiwei Xiao Qiang Wu Sida Luo Chuck Zhang Jeffery Baur Ryan Justice Tao Liu 《Particle & Particle Systems Characterization》2013,30(4):338-345
With incorporation of gold nanoparticles, i.e., nanorods (AuNR) and nanospheres (AuNS), into a polyurethane‐based shape‐memory polymer (SMP) EG‐72D matrix, SMP nanocomposite films capable of being remotely triggered by low‐power laser are fabricated and characterized using UV‐vis‐NIR spectroscopy, X‐ray scattering, and dynamic mechanical analysis (DMA). It is demonstrated that, with incorporation of very low concentration of gold nanorods (≈0.1 wt%), the mechanically programmed EG‐72D/AuNR nanocomposite presents rapid response to low power laser irradiation (785 nm, ≈10 mW). Comparative studies on the laser irradiation response of EG‐72D/AuNS and EG‐72D/AuNR nanocomposite films suggest that AuNRs have significantly higher photothermal conversion efficiency than AuNS and on‐resonance laser irradiation, matching the wavelength of the incident laser with the longitudinal plasmon resonance of AuNR, is necessary to induce the fast response of gold nanoparticle enabled SMP nanocomposites. 相似文献
92.
ZHANG Jingfu XIE Jingyi DENG Zhiwei & LU Zhiheng Key Laboratory for Quantum Information Measurements Department of Physics Tsinghua University Beijing China Center for Quantum Information Tsinghua University Beijing China Department of Materials Science Engineering Beijing Normal University Beijing China Testing Analytical Center Beijing Normal University Beijing China Department of Physics Beijing Normal University Beijing China 《中国科学G辑(英文版)》2005,48(1):57-67
Dense coding using superpositions of Bell-states is proposed. The generalized Grover's algorithm is used to prepare the initial entangled states, and the reverse process of the quantum algorithm is used to determine the entangled state in the decoding measurement. Compared with the previous schemes, the superpositions of two Bell-states are exploited. Our scheme is demonstrated using a nuclear magnetic resonance (NMR) quantum computer. The corresponding manipulations are obtained. Experimental results show a good agreement between theory and experiment. We also generalize the scheme to transmit eight messages by introducing an additional two-state system. 相似文献
93.
本文叙述了在感应耦合等离子体中,原子激发过程可以用台阶式模型来近似,从而证实了激发态粒子数的局部非玻尔兹曼分布是等离子体光学薄性质的必然结果。从理论上讨论了局部非玻尔兹曼分布公式以及分布曲线弯曲时的拐点能量。 相似文献
94.
全息光存储以其高密度、大容量、高速并行数据存取而成为光存储领域的一个重要研究方向。生物光致变色材料———菌紫质是一种新型可擦重写全息记录介质。实验证明了使用菌紫质薄膜进行角度复用和偏振复用全息存储的可行性。利用菌紫质的光致变色特性,采用90°角度复用全息存储光路,在BR-D96N薄膜样品同一位置上实现了6幅全息图存储,并分别读出了无串扰的再现像。利用菌紫质薄膜的光致各向异性进行了偏振复用全息存储,在BR-D96N薄膜样品的同一位置上存储了两幅正交偏振光记录的图像,用原参考光再现和偏振片选择,可分别读出这两幅图像。 相似文献
95.
Zhiwei Zhao Benxue Jiang Yinghua Zhang Yupu Liu Xiaodong Xu Pingxin Song Xiaodan Wang Jun Xu 《中国光学快报(英文版)》2005,3(3)
High-quality neodymium doped GGG laser crystals have been grown by Czochralski (Cz) method. Results of Nd:GGG thin chip laser operating at 1.064 μm pumped by Ti:sapphire laser operating at 808 nm were reported. The slop efficiency was as high as 20%. 相似文献
96.
Tracking an active sound source involves the modeling of non-linear non-Gaussian systems. To address this problem, this paper proposed scaled unscented particle filter (SUPF) algorithm for tracking moving sound source. The particle filter part of the SUPF provides the general probabilistic framework to handle non-linear non-Gaussian systems, and the scaled unscented Kalman filter (SUKF) part of the SUPF generates better proposal distributions by taking into account the most recent observation. Meanwhile, models used in SUPF algorithm were also explored for the sound source motion, observation and the likelihood of the sound source location in the light of the Langevin process. Compared with the conventional PF approach, the simulated results demonstrated that the SUPF algorithm had superior tracking performance. 相似文献
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Christian Taubitz Zhiwei Hu Nils Hollmann Yi‐Ying Chin Karsten Kuepper Vladimir Tsurkan H.‐J. Lin C. T. Chen L. H. Tjeng Manfred Neumann 《固体物理学:研究快报》2010,4(11):338-339
Here we present X‐ray absorption measurements of a vacuum cleaved Fe0.5Cu0.5Cr2S4 single crystal. Measurements at different positions on the cleaved sample surface clearly reveal a difference between the valence state of the Fe ions in the sur‐ face layers and the valency of the Fe ions present in the bulk. These results confirm the findings of recent measurements outlined previously. (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献