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131.
Alignment of liquid crystal and dichroic dye molecules in mixed Langmuir and Langmuir-Blodgett films
A study of dichroic dye-liquid crystal mixtures (guest-host systems) in monolayers formed at a gas-liquid interface (Langmuir films) and at a solid surface (Langmuir-Blodgett films) has been made. As a host 4- n -octyl-4′-cyanobiphenyl (8CB) or 4- n -pentyl-4″-cyano- p -terphenyl (5CT) were chosen, while three dichroic azo dyes with various molecular structures were used as guest species. The dyes were added to the liquid crystal matrices at a concentration corresponding to the whole range of molar fractions and the surface pressure-mean molecular area isotherms for Langmuir films were recorded. On the basis of the isotherms, conclusions about the molecular organization and the miscibility of the components in the ultrathin films were drawn. The Langmuir films were transferred onto the quartz plates at surface pressures below the collapse point. The polarized absorption spectra of the Langmuir-Blodgett films were recorded and information about the alignment and intermolecular interactions in the mixtures of the non-amphiphilic dichroic dyes and the liquid crystals with strongly polar terminal groups were obtained. 相似文献
132.
方差分析自试验设计诞生以来一直是用于分析试验中各因子是否显著的统计方法,对于正交试验设计而言其更是唯一的分析方法.然而,当正交表各列放满了被考虑的各个因子及其交互作用并且各条件组合下只能进行一次试验时,方差分析中的误差项将恒等于0,从而方差分析不再能用于对此试验设计的分析.对此,本文针对使用多水平完备正交表的单次正交试验,提出了一种新的统计分析方法.示例表明:本文提出的检验法不仅解决了方差分析无法胜任的问题,而且在表头设计有空白列从而方差分析仍能实施时,其比方差分析具有更大的局部功效. 相似文献
133.
134.
Existing fusion rules focus on retaining detailed information in the source image, but as the thermal radiation information in infrared images is mainly characterized by pixel intensity, these fusion rules are likely to result in reduced saliency of the target in the fused image. To address this problem, we propose an infrared and visible image fusion model based on significant target enhancement, aiming to inject thermal targets from infrared images into visible images to enhance target saliency while retaining important details in visible images. First, the source image is decomposed with multi-level Gaussian curvature filtering to obtain background information with high spatial resolution. Second, the large-scale layers are fused using ResNet50 and maximizing weights based on the average operator to improve detail retention. Finally, the base layers are fused by incorporating a new salient target detection method. The subjective and objective experimental results on TNO and MSRS datasets demonstrate that our method achieves better results compared to other traditional and deep learning-based methods. 相似文献
135.
136.
氧钒酞菁在激光光盘系统中的应用研究 总被引:3,自引:0,他引:3
氧钒酞菁在激光光盘系统中的应用研究董长征,沈永嘉,任绳武(华东理工大学精细化工研究所上海200237)袁海俊(中国科学院上海光学精密机械研究所上海201800)关键词:信息储存,激光光盘,功能染料,氧钒酞菁自1972年Philips公司推出激光光盘(... 相似文献
137.
轴向进气位置对转静盘腔传热影响的分析 总被引:2,自引:1,他引:1
本文对具有不同轴向进气位置的两个转静盘腔的流动和传热进了数值模拟。这两个盘腔除进气位置不同外,具有相同的几何结构,进气流量及温度边界条件。在盘腔的核心区采用标准k-ε紊流模型,近壁区采用单方程模型。求解并分析了包括流体域,固体域的整体温度分布以及流固界面上的努塞尔数分布。 相似文献
138.
S. Sankarapapavinasam 《Journal of polymer science. Part A, Polymer chemistry》1993,31(5):1105-1109
The kinetics and mechanism of electropolymerization of m-aminophenol (mAP) has been investigated in acetonitrile (AN) and methanol (MeOH) media. The rate of polymerization is found to be proportional to [mAP] (current)0.5 at moderate current densities; at higher current densities, the rate of polymerization is independent of current density. A suitable mechanism has been proposed and the rate equation is derived to explain the observed factors. Rotating disc voltametry revealed that at low current densities, the rate of polymerization is charge controlled, while at high current densities it is diffusion controlled. The physicochemical characteristics of AN make it a better solvent than MeOH. © 1993 John Wiley & Sons, Inc. 相似文献
139.
本文对作者提出的圆盘式折射率计里的光线,特别是非平行光线的传输问题进行了详尽的分析.分析及计算机计算表明,圆盘式折射率计的线性度甚至可对非平行光线仍良好保持.圆盘内光线的多次反射克服了非全内反射的影响,使得输出线性度仍然得以保持.有关参数设计及改进精度的讨论亦在本文作了讨论. 相似文献
140.
In the present paper lattice packings of open unit discs are considered in the Euclidean plane. Usually, efficiency of a packing
is measured by its density, which in case of lattice packings is the quotient of the area of the discs and the area of the
fundamental domain of the packing. In this paper another measure, the expandability radius is introduced and its relation
to the density is studied. The expandability radius is the radius of the largest disc which can be used to substitute a disc
of the packing without overlapping the rest of the packing. Lower and upper bounds are given for the density of a lattice
packing of given expandability radius for any feasible value. The bounds are sharp and the extremal configurations are also
presented. This packing problem is related to a covering problem studied by Bezdek and Kuperberg [BK97].
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献