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121.
122.
Min Wu Yan Lv Zhengping Fu Jiao Xu Ting Guo Yongxun Zhao 《Applied Surface Science》2010,256(23):7125-9486
The simultaneous Ag loaded and N-doped TiO2 hollow nanorod arrays with various contents of silver (Ag/N-THNAs) were successfully synthesized on glass substrates by one-pot liquid phase deposition (LPD) method using ZnO nanorod arrays as template. The catalysts were characterized by Raman spectrum, field-emission scanning electron microscopy (FESEM), high-resolution transmission electron microscope (HRTEM), ultraviolet-vis (UV-vis) absorption spectrum and X-ray photoelectron spectroscopy (XPS). The results suggest that AgNO3 additive in the precursor solutions not only can promote the anatase-to-rutile phase transition, but also influence the amount of N doping in the samples. The photocatalytic activity of all the samples was evaluated by photodegradation of methylene blue (MB) in aqueous solution. The sample exhibited the highest photocatalytic activity under UV light illumination when the AgNO3 concentration in the precursor solution was 0.03 M, due to Ag nanoparticles acting as electron sinks; When the AgNO3 concentration was 0.07 M, the sample performed best under visible light illumination, attributed to the synergetic effects of Ag loading, N doping, and the multiphase structure (anatase/rutile). 相似文献
123.
Elena Fernández Manuel Ortuño Andrés Márquez Rosa Fuentes Inmaculada Pascual 《Optik》2010,121(2):151-158
Holographic data pages were stored in a polyvinyl alcohol (PVA)/acrylamide (AA) photopolymer. This material is formed of AA photopolymers which are considered interesting materials for recording holographic memories. A liquid crystal device was used to modify the object beam and store the data pages in the material. During the storage process, some parameters like exposure time, beam ratio and reading beam intensity were controlled to obtain high image quality after the reconstruction process. The bit error rate (BER) was calculated fitting the histograms of the images to determine what parameters improve the quality of the images. 相似文献
124.
提出了利用数字全息干涉术可视化观测液相扩散过程.实验中,采用马赫-曾德干涉仪光路记录乙醇与水之间两相扩散过程的多幅数字全息图;再通过数值再现不同扩散状态的波前相位分布,获得液体中的摩尔浓度分布;最后,根据菲克定律获得两相流扩散系数.结果表明:利用数字全息干涉术可实现对液相扩散传质过程的快速、实时及高精度测量;该方法还具有可实现远程监控、拥有大量微观数据的优点;此外,采用文中全息干涉光路结合波分与角分复用技术可实现多相流扩散系数的测量,为获得溶液中非线性变化特征参量提供了有效技术手段. 相似文献
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采用分子动力学方法对液态Mg7Zn3合金的快速凝固过程进行了模拟研究,并采用双体分布函数、Honeycutt-Andersen键型指数法、原子团类型指数法(CTIM)以及遗传跟踪等方法对凝固过程中团簇结构的形成、演变特性进行了分析.结果表明:在以冷速为1×1012 K ·s-1的凝固过程中, Zn-Zn原子之间的相互成键的概率明显增加,形成以1551,1541,1431键型为主的非晶态结构.其特征键型1551随温度变化
关键词:
液态MgZn合金
快速凝固过程
微观结构演变
分子动力学模拟 相似文献
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129.
V.S.U. Fazio L. Komitov C. Radüge S.T. Lagerwall H. Motschmann 《The European physical journal. E, Soft matter》2001,5(3):309-315
The influence of capillary flow on the alignment of the nematic liquid crystal 5CB on fatty acid Langmuir-Blodgett monolayers
was studied by optical second-harmonic generation (SHG). The surface dipole sensitivity of the technique allows probing the
orientation of the first liquid crystal monolayer in the presence of the liquid crystal bulk. It was found that capillary
flow causes the first monolayer of liquid crystal molecules in contact with the fatty acid monolayer to be oriented in the
flow direction with a large pretilt (78 degrees), resulting in a quasi-planar alignment with splay-bend deformation of the
nematic director in the bulk. The large pretilt angle also suggests that the Langmuir-Blodgett film itself is affected by
the flow. The quasi-planar flow-induced alignment was found to be metastable. Once the flow ceases, circular domains of homeotropic
orientation nucleate in the sample and expand until the whole sample becomes homeotropic. This relaxation process from flow-induced
quasi-planar to surface-induced homeotropic alignment was also monitored by SHG. It was found that in the homeotropic state
the first nematic layer presents a pretilt of 38 degrees almost isotropically distributed in the plane of the cell, with a
slight preference for the direction of the previous flow.
Received 8 November 2000 and Received in final form 12 March 2001 相似文献
130.