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961.
Mei‐Yi Liao Cheng‐Ham Wu Ping‐Shan Lai Jiashing Yu Hong‐Ping Lin Tzu‐Ming Liu Chih‐Chia Huang 《Advanced functional materials》2013,23(16):2044-2051
The development of fluorescent iron oxide nanomaterials is highly desired for multimodal molecular imaging. Instead of incorporating fluorescent dyes on the surface of iron oxides, a ligand‐assisted synthesis approach is developed to allow near‐infrared (NIR) fluorescence in Fe3O4 nanostructures. Using a trimesic acid (TMA)/citrate‐mediated synthesis, fabricated Fe3O4 nanostructures can generate a NIR two‐photon florescence (TPF) peak around 700 nm under the excitation by a 1230‐nm femtosecond laser. By tailoring the absorption of Fe3O4 nanostructures toward NIR band, the NIR‐TPF efficiency can be greatly increased. Through internal etching, surface peeling, and ligand replacement, spectroscopic results validated that such resonantly enhanced NIR‐TPF is mediated by surface states with strong NIR‐IR absorption. This TPF signal evolution can be generalized to other iron oxide nanomaterials like magnetite nanoparticles and α‐Fe2O3 nanoplates. Using the developed fluorescent Fe3O4 nanostructures, it is demonstrated that their TPF and third harmonic generation (THG) contrast in the nonlinear optical microscopy of live cells. It is anticipated that the synthesized NIR photofunctional Fe3O4 will serve as a versatile platform for dual‐modality magnetic resonance imaging (MRI) as well as a magnet‐guided theranostic agent. 相似文献
962.
属性证书的管理与应用 总被引:1,自引:0,他引:1
公钥基础设施PKI很好地解决了身份认证问题,但是无法满足权限管理问题,而属性证书(Attribute Certificate)提供了全新的方法来解决细粒化访问控制问题,将PKI框架扩展到了授权领域。本文就当前有关属性证书的标准和相关文献,针对其技术概貌作了一些综述,并介绍了属性证书的应用。 相似文献
963.
964.
具有高清晰度三维图像的模压全息图母版制作技术 总被引:2,自引:0,他引:2
从理论上分析了在模压三维全息图母版的记录光路中,为消除或减小像散和像场弯曲以及扩展照明光源产生的像模糊所应采取的参数设置。试验结果表明用此方法制作的模压三维全息图即使在漫射照明光下亦能呈现出清晰、明亮的图像。 相似文献
965.
966.
967.
孤子效应脉冲压缩中的三阶色散抑制 总被引:4,自引:2,他引:4
提出并通过数值计算证明,若周期性地改变光纤的三阶色散系数,则可有效地抑制三阶色散对色散位移光纤中孤子效应脉冲压缩的影响 相似文献
968.
969.
Long Keping Cheng Shiduan 《电子科学学刊(英文版)》1999,16(2):123-129
In this paper, the concept of the Shortest-Route Traffic Matrix(SRTM) was first presented, and the generalized formula for computing ring capacity requirement in use of SRTM is given. Then, a new capacity design algorithm which is based on SRTM was presented for Synchronous Digital Hierarchical(SDH) Bi-directional Self-Healing Ring (BSHR). The algorithm simulation results demonstrate that this algorithm is very efficient for SDH BSHR capacity design and can make less project investment and make high utilization of lines and equipment. By means of the algorithm in this paper, capacity optimization assignment for SDH Hierarchical Self-Healing Ring (HSHR) and for ATM Virtual Path (VP)-based Self-Healing Ring (SHR) is also discussed. 相似文献
970.
Resolving Deep Sub-Wavelength Scattering of Nanoscale Sidewalls Using Parametric Microscopy 下载免费PDF全文
Nagendra Parasad Yadav Ji-Chuan Xiong Wei-Ping Liu Wei-Ze Wang Yun Cao Ashish Kumar Xue-Feng Liu 《电子科技学刊:英文版》2021,19(3):233-242
The quantitative optical measurement of deep sub-wavelength features with sub-nanometer sensitivity addresses the measurement challenge in the semiconductor fabrication process. Optical scatterings from the sidewalls of patterned devices reveal abundant structural and material information. We demonstrated a parametric indirect microscopic imaging (PIMI) technique that enables recovery of the profile of wavelength-scale objects with deep sub-wavelength resolution, based on measuring and filtering the variations of far-field scattering intensities when the illumination was modulated. The finite-difference time-domain (FDTD) numerical simulation was performed, and the experimental results were compared with atomic force microscopic (AFM) images to verify the resolution improvement achieved with PIMI. This work may provide a new approach to exploring the detailed structure and material properties of sidewalls and edges in semiconductor-patterned devices with enhanced contrast and resolution, compared with using the conventional optical microscopy, while retaining its advantage of a wide field of view and relatively low cost. 相似文献