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91.
92.
K HondaM Yoshimura R UchikadoT Kondo Tata N Rao D.A TrykA Fujishima M WatanabeK Yasui H Masuda 《Electrochimica acta》2002,47(27):4373-4385
Electrochemical characteristics for several redox systems at diamond films with highly ordered nanometer-scale cylindrical pores (‘nano-honeycombs’) were examined with cyclic voltammetry (CV) and electrochemical impedance measurements. The cyclic voltammetric anodic-cathodic peak separations for these nano-honeycomb electrodes were in the same range as those for polished polycrystalline diamond films, indicating that the involvement of the oxygen-terminated surface of the nano-pore walls, which should give rise to large peak separations for certain redox couples was only slight. Moreover, the peak currents in the CV were not enhanced to the extent expected on the basis of the roughness factors of the nano-honeycomb films. Ac impedance plots results indicated the existence of a concentration gradient of the reactant in the nano-pores, which is in agreement with theoretical predictions for charge transfer reactions in porous electrodes. The average concentration of the reactant (Fe2+/3+) inside the nano-pores was a factor of ca. 80 lower than that in the bulk electrolyte. The results of the impedance analysis also indicated an increase in the reaction resistances with decreasing pore diameters. 相似文献
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Electroporation creates aqueous pathways by short high-voltage pulses resulting in a transient perme- abilization of stratum corneum and an increase in the transdermal delivery rate.However the aqueous pathways will reseal after pulsing,which leads to the rapid drop of transdermal flux.In the present study,the surfactants were added to the donor solution to hinder the shrinkage and resealing of the electropore,and to prolong the lifetime of the aqueous pathways with the consideration that the surfactants could reduce the surface energy of the electropore. These effects of surfactants were demonstrated by the dynamic electrical resistance of the skin and the fluorescent imaging of the local transport regions.Piroxicam(PIX)was transported percutaneously in the presence of surfactants in vitro.Owing to the longer lifetime of aqueous pathways,together with the promotion of PIX availability at the barrier exterior and the improvement in the partition of PIX into the aqueous pathways,the presence of surfactants led to a remarkable increase in the transdermal delivery rate during electroporation and a significant growth of the accumulative transdermal amount of PIX. 相似文献
95.
大坝安全不仅影响工程效益,还影响人民的生命和财产安全,溃坝洪水模拟可以对水库大坝的失事影响做出评估,对制定应急预案和防洪减灾具有重要意义。以深圳市龙华新区民治水库及下游片区为研究对象,基于MIKE FLOOD将MIKE11模型和MIKE21模型进行动态耦合,对溃坝洪水在下游的演进过程进行仿真模拟。模型采用瞬间溃(瞬间部分溃和瞬间全溃)以及逐渐溃两种溃决方式,分别模拟4种工况下的溃口流量过程线以及下游洪水演进过程。结果表明:瞬间溃的洪峰流量较大,出现在溃坝开始时刻,而逐渐溃的洪峰流量相对较小,出现在渗透破坏变形发展至上部坝体坍塌时刻,之后均随库区水位逐渐降低,下泄流量变小,直至库区水体排空。溃坝洪水对上游地区横岭村附近破坏较大,淹没水深较深。民治河中游段居民和商业区附近洪水流速接近5 m/s,对建筑物有一定破坏力,左侧向南村地势较低,淹没情况最为严重,并且在洪水消退后仍有3 m左右积水。民治河下游地区在洪水消退后也有少量积水。 相似文献
96.
美白产品始终是夏季护肤品市场竞争的焦点,旁氏推出“日夜美白不停顿”的新概念以应对传统美白产品的挑战,并利用策略发展和广告创意的源动力——“消费者洞察力”概念推出了一套精准的传播策略和创意出色的广告,对消费者产生了很强的吸引力。 相似文献
97.
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99.
Eiichi Hoshino Kazunari Maruta Yasunao Wada Kazuo Mori 《Journal of the American Oil Chemists' Society》1995,72(7):785-791
The interaction of highly purified alkaline protease fromBacillus sp. KSM-K16 with the horny cells of human skin contained in skin grime was directly visualized by electron microscopy. It
became clear that the protease first penetrates the horny cells and then adsorbs, mainly onto the internal structure of the
cells at the initial stage of hydrolysis, and directly hydrolyzes the keratin filaments, though the marginal band surrounding
them retains its original shape. Then, hydrolysate produced from the keratin filaments flows out of the cell, and early in
the hydrolysis process keratin filaments decrease and then disappear, leaving a marginal band, i.e., the cell turns to a hollow
state. As a result, the remaining marginal band loses support from inside the cell, thus promoting cleavage and dispersion.
Until this stage in the protease reaction, the remarkable liberation of hydrolysis products as water-soluble protein does
not occur. 相似文献
100.
为实时提取三维实体表面,提出一种基于GPGPU并行计算的实体表面实时提取方法。在分析深度剥离算法原理和GPU图形绘制管线的基础上,给出在GPU上利用深度剥离算法实现实时提取三维实体表面的算法;通过OpenGL的高级着色语言GLSL控制GPU的图形绘制管线实现了该算法,给出其伪代码。以龙、叶轮和刀具扫描体的模型为应用实例验证了该算法效果良好,特别是对于刀具扫描体表面的提取,可满足实时性要求。 相似文献