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采用两种光致变色俘精酸酐体系化合物[1,2,4-三甲基-5-苯基-3-吡咯甲叉(异丙叉)俘精酸酐和对-N,N-二甲基苯基-2-甲基-3-恶唑甲叉(异丙叉)俘精酸酐]制备了单层双色聚甲基丙烯酸甲酯(PMMA)复合薄膜感光记录材料。采用双波长(650nm和488nm)图像存储和读出光路,实现了用两种波长在双色复合薄膜的同一位置同时记录两幅图像。当分别用各自对应的波长读出时,两幅图像各自获得了高衬比度,且二者之间的串扰很小,证明了在双色光致变色俘精酸酐材料上进行双波长复用图像光存储的可行性。 相似文献
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As the information acquisition of mobile terminals such as mobile phones becomes more and more convenient, new media has gradually become the major way for people to obtain information. The WeChat public account is one of the main channels for people to receive information in their daily lives. This article introduces some practices of using the WeChat public account "Chemical Science Park" to carry out popular science work, as well as the difficulties encountered in the process and reflections. 相似文献
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BR-D96N is a kind of genetically site-specific mutant of bacteriorhodopsin (BR) with obvious photochromic effect. Compared to the wild type BR, the lifetime of M state of BR-D96N is prolonged to several minutes so that the photochromic kinetics and the intermediates formation can be studied by the conventional spectra analysis. In the experiment, the absorption spectra of the sample at different time after light illumination are measured with spectrophotometer. By fitting and analyzing the variation of the spectra, we suppose there are three main states in the photochromic process, i.e. B state (light-adapted state), M state and D state (dark-adapted state). The absorption spectra of the B state, M state and D state are extracted from the experimental data based on this three-state model and the spectra at various time are fitted with the least square method. So, the variations of population percentages of the M state, B state and D state are obtained and the M state and B state lifetimes are estimated. In another way, from measuring the absorption dynamics at 407 nm and 568 nm, the M state and B state lifetimes are also obtained by two exponential data fitting, which give coincident results with those of the spectra analysis. 相似文献
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According to the risk management process of financial markets,a financial risk dynamic system is constructed in this paper.Through analyzing the basic dynamic properties,we obtain the conditions for stability and bifurcation of the system based on Hopf bifurcation theory of nonlinear dynamic systems.In order to make the system’s chaos disappear,we select the feedback gain matrix to design a class of chaotic controller.Numerical simulations are performed to reveal the change process of financial market risk.It is shown that,when the parameter of risk transmission rate changes,the system gradually comes into chaos from the asymptotically stable state through bifurcation.The controller can then control the chaos effectively. 相似文献
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We investigate the photoinduced anisotropy of a photochromic material of pyrrylfulgide/PMMA films. It is proven that when the film is illuminated with a linear polarization light, an optical axis that has the same polarization as the excitation light could be induced in the film. A matrix of light spots with different polarizations is recorded 相似文献
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可擦写俘精酸酐/PMMA薄膜的全息记录特性研究 总被引:10,自引:10,他引:0
对一种新型可擦写有机光致变色材料-吡咯俘精酸酐的光全息记录特性进行了实验研究.用涂布法制成厚度约10 μm 的吡咯俘精酸酐/PMMA聚合物薄膜.样品无色态吸收峰在373 nm处,经紫外光照射发色后,变为呈色态,其吸收峰移动到626 nm处,呈色态在氦氖激光照射下可以重返为无色态.无色态和呈色态在室温下都是稳定的.以呈色态吡咯俘精酸酐/PMMA薄膜作为记录材料,以氦氖激光作为记录光,分别建立了双光束干涉衍射记录装置和四波耦合实验系统.实验测得该薄膜的空间分辨率至少可以达到1680 lines/mm,一级衍射效率大于2%,全息记录中的最佳曝光量约为1 J/cm2.实验测量了衍射效率与曝光量的特性曲线,分析了衍射光强度和光斑模式随曝光时间的变化关系. 相似文献
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本文纠正了论文“de Sitter空间中具有平行中曲率的完备类空子流形”证明中的一些失误,证明了de Sitter空间中具有平行中曲率的n维完备类空子流形的—个刚性定理. 相似文献