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991.
Polyethersulfone(PES)film with regular microporous structure was formed using dichloromethane as the solvent via water vapor induced phase separation(VIPS).The effects of solution concentration,atmospheric humidity and temperature,as well as molecular weight of PES on the surface morphology of the polymer film were investigated.The surface morphology characterized by SEM showed that the pore size reduced as the solution concentration increased.There was an optimum range of relative humidity for the formation of regular pore structure, which was from 60%to 90%at concentration of 20 g·L-1 and 20°C.With the atmospheric temperature varied from 20 to 30°C,the pore became larger and the space between pores increased.The pore size in the PES film with low molecular weight was smaller than that with high molecular weight. 相似文献
992.
Polymer films consisting of nematic liquid crystal (LC) droplets and polymer networks were prepared by using a low-energy electron beam to irradiate a homogeneous mixture of nematic LC and bifunctional methacrylate monomer. Influences of such polymerization conditions as polymerization temperature, monomer concentration, and radiation energy on electrooptical properties of the compound films were examined. The polymer yield, affecting to a large extent the film properties, depended on the monomer concentration and the radiation energy. Compound films, which have a switching function from the scattering state to transparency by applying approximately 20–30 V between the two sides of the film, were obtained. In addition, it was found that a compound film with excellent electrooptical properties was prepared by changing impure LC in the droplets into pure LC. © 1997 John Wiley & Sons, Inc. J Appl Polym Sci 65:1675–1681, 1997 相似文献
993.
用电活性分子——硬脂酸二茂铁酯L-B膜修饰了薄膜CdSe电极,在单色光650nm光照下用循环伏安法研究修饰的薄膜电极的光电化学性能。研究结果指出经多层L-B膜修饰后,薄膜CdSe电极的,I-V性能和光稳定性都有明显改善。用界面能级关系讨论了硬脂酸二茂铁酯L-B膜在光照的CdSe薄膜/Fe(CN)_6~(4-)溶液界面起传递电荷的中介作用,加速了界面的电荷转移。 相似文献
994.
995.
采用电沉积方法在不同导电基体上制备出具有电化学控制离子交换(ESIX)性能的电活性NiHCF(nickel hexacyanoferrate)薄膜.在1 mol8226;L-1 KNO3溶液中采用电势循环可逆地置入与释放碱金属离子,比较了铂、铝和石墨基体上薄膜的电活性、离子交换容量及再生能力;在1 mol8226;L-1(KNO3+CsNO3)混合溶液中测定了不同浓度下薄膜的伏安特性曲线和电化学交流阻抗谱,分析了薄膜对Cs/K离子的选择性.重点考察了制膜液组成对薄膜电化学性能的影响,通过EDS测定薄膜组成并结合循环伏安曲线分析了薄膜组成和结构与其电化学特性之间的关系.实验表明,3种基体材料上均能制得性能稳定的NiHCF膜,铝和石墨基体上的NiHCF薄膜同样具有良好的ESIX性能;控制制膜液组成可得到不同组分占优的膜,由此可筛选较为理想的ESIX膜材料. 相似文献
996.
With the help of simulations based on energy minimization, we have studied the effect of roughness of a rigid contactor with sinusoidal and step patterns on the adhesion-debonding cycle of a soft thin elastic film. The surface instability engendered by attractive forces between the contactor and the film produces a regularly spaced array of columns in the bonding phase. The inter-column spacing is governed largely by periodicity of the contactor pattern. Decreased periodicity of the pattern favors intermittent collapse of columns rather than a continuous peeling of contact zones. An increase in the amplitude of roughness decreases the maximum force required for debonding and increases the snap-off distance. The net effect results in a reduced work for debonding. Introduction of noise and increased step-size in simulations decreases the pull-off force and the snap-off distance, as in the case of a smooth contactor. Finally the study reveals that a patterned contactor can be used as a potential template in the patterning of soft interfaces. 相似文献
997.
Fe-doped Ba0.65Sr0.35TiO3 (BST) thin films have been fabricated on Pt/Ti/SiO2/Si substrate using the sol–gel method. The structural and surface morphology, dielectric, and leakage current properties of undoped and 1 mol% and 2 mol% Fe-doped BST thin films have been studied in detail. The results demonstrate that the Fe-doped BST films exhibit improved dielectric loss, tunability, and leakage current characteristics as compared to the undoped BST thin films. The improved figure of merit (FOM) of Fe-doped BST thin film suggests a strong potential for utilization in microwave tunable devices. 相似文献
998.
用平膜法制备了抗菌双向拉伸聚丙烯(BOPP)薄膜,分别讨论了分子组装抗菌母料及载银复合物抗菌母料对薄膜抗菌效果、雾度、光泽度、拉伸强度、热封强度及起始热封温度的影响。分子组装类抗菌薄膜的抗菌效果略优;除载银复合物抗菌母料对薄膜雾度影响较大而用途受限外,上述两种抗菌母料对薄膜的抗张强度、光泽度、热封强度及起始热封温度并无显著影响。 相似文献
999.
1000.
On some properties of PZT-NZF composite films manufactured by hybrid synthesis route 总被引:1,自引:0,他引:1
Composite magnetoelectric films using ferroelectric lead zirconate titanate (PZT) and ferromagnetic nickel zinc ferrite (NZF) were prepared using the combination of sol-gel and hydrothermal process on Pt/Ti/SiO2/Si substrates. The thickness was estimated ∼2 μm using cross-sectional SEM. Structure, morphology and electro-magnetic characterization were assessed using XRD, XPS, SEM, dielectric, leakage current, ferroelectric, and magnetic property analyze. The composite films exhibit coexistence of ferroelectric and ferromagnetic ordering at room temperature with a remnant polarization (Pr), and coercive field (Ec) of 1.2 μC/cm2 and 7.8 kV/cm, respectively, and saturation magnetization (Ms) ∼20 emu/cm3. Polarization improved ∼5.2% upon poling the composite film using a magnetic field of 1 T. 相似文献