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61.
Fabrication of Alumina Films with Three-Dimensional Ordered Macropores by Self-Assembly of Binary Colloidal Spheres 总被引:1,自引:0,他引:1 下载免费PDF全文
We present a new process to obtain a three-dimensional ordered macroporous structure (3DOM). The 3DOM films were fabricated using a coassembly of monodispersed polystyrene spheres and alumina hydroxide sols in aqueous suspensions on a vertical substrate followed by a calcination treatment. The 3DOM film structure, quality and morphology have been characterized by scanning electron microscopy and transmission spectra. 相似文献
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本文介绍了主要由意大利政府资助和支持的三个国际性科学组织:国际理论物理中心(ICPP)、第三世界科学院(TWAS)、国际科学和高技术中心(ICS).第三世界国家的科学工作者根据需要,可以向这三个组织申请资助,以开展有关的科学交流和研究活动。 相似文献
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用2660(?)的紫外激光解离PbCl_2分子时,发现在3740(?)和3734(?)波长上有较强的受激辐射输出.根据它们的光谱特性和铅原子的能级结构判断,这些辐射是基于双光子解离PbCl_2分子得到的铅原子在6p~(23)P_2亚稳能级上的布居而产生的光泵共振激光辐射和受激喇曼散射.提出了描述整个过程的理论模型,通过拟合实验结果,确定了2660(?)激光双光子解离PbCl_2产生6p~(23)P_2亚稳态铅原子的光解系数.当PbCl_2分子密度为N_(00)=6.21×10~(16)cm~(-3)时,光解产生的铅原子在6p~(23)P_2和6p~(21)D_2这两个亚稳态的最大布居数近似相等,称为2.0×10~(16)cm~(-3). 相似文献
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1.IUPAP简介 纯粹与应用物理国际联合会(简称IUPAP)是一国际性的学术团体,由三十四个国家物理机构的代表组成,每三年召开一次代表大会.代表大会选举产生执委会委员和各专业委员会委员.执委会负责日常事务,通常每年召开一次执委会议. IUPAP下设18个专业委员会,分别是: C_2──符号、单位、名词、原子质量和基本常数委员会; C_3──热力学和统计力学专业委员会; C_4──字苗射线专业委员会; C_5──低温物理专业委员会; C_6──出版专业委员会; C_8──半导体专业委员会; C_9──磁学专业委员会; C_(10)──凝聚态结构和动力学专业… 相似文献
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Optical properties of the direct-coupled Y-branch filtersby using photonic crystal slabs 总被引:1,自引:0,他引:1 下载免费PDF全文
We fabricated a new type of two-dimensional photonic crystal slab filter. The
resonant cavities were directly put into the waveguide arms. The optical
transmissions of the filters were measured and the results show that the optimized
two-channel filters give good intensity distribution at the output ports of the
waveguide. A minimum wavelength spacing of 5~nm of the filter outputs isrealized
by accurately controlling the size of the resonant cavities. 相似文献
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Near-field imaging of a square-lattice metallic photonic-crystal slab at the second band 总被引:1,自引:0,他引:1 下载免费PDF全文
Imaging properties of a two-dimensional photonic crystal slab lens are
investigated through the finite-difference time-domain method. In this
paper, we consider the photonic crystal slab consisting of a square lattice
of square metallic rods immersed in a dielectric background. Through the
analysis of the equifrequency-surface contours and the field patterns of a
point source placed in the vicinity of the photonic crystal slab, we find
that a good-quality image can form at the frequencies in the second
TM-polarized photonic band. Comparing the images formed at different
frequencies, we can clearly see that an excellent-quality image is formed by
the mechanisms of simultaneous action of the self-collimation effect and the
negative-refraction effect. 相似文献
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Controlling the focusing properties of a triangular-lattice metallic photonic-crystal slab: 总被引:1,自引:0,他引:1 下载免费PDF全文
This paper studies the focusing properties of a two-dimensional
photonic crystal (PC) slab consisting of a triangular lattice of
metallic cylinders immersed in a dielectric background. Through the
analysis of the equifrequency-surface contours and the field
patterns of a point source placed in the vicinity of the PC slab, it
finds that both the image distance and image quality can be
controlled by simply adjusting the refractive index of the
background material. 相似文献
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