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91.
Effect of Li+ ions on structure,properties, and actuation of cellulose electro‐active paper actuator
We have reported an electro‐active paper actuator from regenerated cellulose. After dissolving cellulose fibers with a solution of lithium chloride in N,N‐dimethylacetamide, cellulose was regenerated by combining distillation of cellulose solution along with washing with the mixture of deionized water, isopropyl alcohol, and running water. However, the effect of Li+ ions on structure, properties, and the actuation behavior of the actuator was not studied. This article describes the changes in these parameters when the Li+ ions are removed by subjecting it to different running water exposure time. The structure and properties of cellulose electro‐active paper and its actuation behavior were studied. As Li+ ions content reduced from 4354.17 to 10.26 ppm by increasing the exposure time of running water, crystallinity, Young's modulus, and bending displacement decreased. Details about the investigation have been explained. This elimination of ions is important to increase the piezoelectric effect in EAPap by decreasing the ion migration effect. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci 2008 相似文献
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Zheng Liu Mingqin Xuan Zhaohui Zhao Yufeng Cong Kejian Liao 《Petroleum Science and Technology》2003,21(7):1317-1325
In this article, the compatibilities between different components of a base asphalt and styrene butadiene styrene (SBS) have been analyzed from microscopic structures. Specifically, the asphalt was separated into three components: saturates, aromatics, and resins, by Solvent Recycled Absorption Chromatography Separation Technology (SRACST). The compatibilities between these different components and the polymer were compared with the help of Fluorescence Microscope (FM) with which the existing state of the polymer SBS in these different components could be examined obviously. The modified effects indicated that aromatics could cause SBS swollen and, resins dissolved SBS better than saturates, though both the two components could partially dissolve SBS and the two mixtures presented two immiscible phase systems. In order to further investigate the compatibility between aromatics and SBS, from macroscopic properties, an additive rich in aromatics was added to the SBS/asphalt mixture, and the result was satisfactory. 相似文献
96.
在不同反应温度条件下采用原位聚合法在石英基片上制备了聚苯胺薄膜.对薄膜样品进行了紫外光谱、SEM、电性能表征。实验结果表明,过高的合成温度会加速聚合反应过程,抑制膜厚的增长,引起薄膜的热降解,进而对样品的导电性产生不良影响。根据生长速率与合成温度的依赖关系,估算了聚合反应的活化能Ea=34.4kJ/mol。 相似文献
97.
针对有限元仿真分析中结构自振周期减小的问题,讨论了几种主要的影响因素,并借用商品化设计软件TBSA,ETABS 和有限元分析软件ANSYS,通过对一个简单结构的多次计算,比较了这些因素的影响大小。 相似文献
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The rate of filtration and the water content of cake are influenced by the existence of a dense skin in a highly compressible
cake. The phenomenon of the dense skin has been rarely studied, and its existence has not been verified experimentally. In
this study, the porosity variation in a very compressible cake is measured by using a new experimental apparatus, and with
this the existence of dense skin has been established experimentally. ‘Unified theory on solid-liquid separation’, a recently
developed theory, is utilized for calculating the porosity variation in a very compressible cake. 相似文献
100.