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991.
Tungsten oxide (WO3) films were prepared on indium–tin oxide (ITO) glass by sol–gel method. The influence of annealing temperature on the structural, morphological, optical, electrochemical, and electrochromic properties has been investigated. The film annealed at 250 °C with an amorphous structure exhibits a noticeable electrochromic performance, such as the highest optical modulation of 58.5 % at 550 nm, high electrochemical stability, and excellent reversibility (Q b/Q c?=?96.3 %). An electrochromic (EC) device based on WO3/NiO complementary structure shows improved performance. It exhibits high optical transmittance modulation of 62 % at 550 nm, excellent cycling stability, and relatively fast electrochromic response time (10 s for coloration and 19 s for bleaching). 相似文献
992.
993.
994.
由于大部分环境样品的浓度非常低,为了实现其直接检测,提出将一种集成化的微型富集器应用到色谱系统中。富集器可实现色谱系统的进样与样品富集,能将色谱仪的检测限提高1~2个数量级。设计的富集器采用了高容量4平行通道结构,沟道内填充了高吸附率的Tenax-TA吸附材料,来实现对环境样品中挥发性有机化合物组分的富集。此外,为了密闭热解吸过程中所释放的组分,在微型富集器后集成了微型阀。试验结果表明,研制的微型富集器取得了15倍以上的富集因子。而且,通过微阀的控制,色谱峰的拖尾和峰展宽得到了有效的控制。因此,该微型富集器可广泛应用到环境样品的快速检测中,提高各检测器对复杂环境的适应能力。 相似文献
995.
996.
997.
998.
We examined the thermal stability of amorphous silicon oxycarbide (SiOC) and crystalline Fe composite by in situ and ex situ annealing. The Fe/SiOC multilayer thin films were grown via magnetron sputtering with controlled length scales on a surface-oxidized Si (100) substrate. These Fe/SiOC multilayers were in situ or ex situ annealed at temperature of 600 °C or lower. The thin multilayer sample (~10 nm) was observed to have a layer breakdown after 600 °C annealing. Diffusion starts from low groove angle triple junctions in Fe layers. In contrast, the thick multilayer structure (~70 nm) was found to be stable and an intermixed layer (FexSiyOz) was observed after 600 °C annealing. The thickness of the intermixed layer does not vary as annealing time goes up. The results suggest that the FexSiyOz layer can impede further Fe, Si and O diffusion, and assists in maintaining morphological stability. 相似文献
999.
The static and evolutionary properties of two-dimensional cellular structures, or froths, are discussed in the light of recent work on structuring of the froth into concentric shells. Of interest is the dual role of a topological dislocation (defect) in an otherwise uniform froth, considered both as a source of disorder and also as a source generating a shell-structured froth. We present simulations on an initially uniform hexagonal froth. A defect is introduced by forcing either a T1 or T2 process in the stable structure, after which the froth is allowed to evolve according to von Neumann's law. In the first case, topological inclusions are found in the first few layers early in the evolution. In the second case, no inclusions appear over the entire evolutionary period. The growing disorder (as measured by the second moment of the side distribution,
2) is isotropic. For the special case of a T2-formed froth in a uniform network, the SSI structure is retained with
20 only for the zeroth, first, and second layers. The ratio between topological perimeter and radius of the shells is close to 6, the value for a hexagonal froth. 相似文献
1000.