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51.
The cutoff wavelength of dominant mode in unilateral finline is analyzed by finite element method. The cutoff wavelength can be changed by adjusting the thickness of metallic fins and dielectric constant of dielectric substrate. Numerical results provide in this paper have important values in practical applications. 相似文献
52.
A 3D hierarchical computational model of damage and strength of wood is developed. The model takes into account the four scale microstructures of wood, including the microfibril reinforced structure at nanoscale, multilayered cell walls at microscale, hexagon-shape-tube cellular structure at mesoscale and annual rings at the macroscale. With the use of the developed hierarchical model, the influence of the microstructure, including microfibril angle (MFA), the cell shape and the wood density (annual ring structure), differences between earlywood and latewood as well as microstructural arrangements and cellulose strength distributions on the tensile strength of wood is studied numerically. Good agreement of the theoretical results with experimental data has been obtained. 相似文献
53.
简述铝基板冲板模具的设计、调试的要点及发生问题的解决方案,重点叙述了通过利用压板翘模具得以成功解决铝基板冲板后板翘的问题。 相似文献
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介绍澳大利亚和新加坡在交通行业从业人员培训和考试的现状,以及相关职业资格制度的建设,对上海如何加快推进交通行业职业资格工作带来的启示。 相似文献
57.
采用共焦Z扫描系统,以λ=532nm.脉冲宽度0.7ns.重复频率15.79kHz的脉冲半导体激光器作为入射光源,研究了AgOx超分辨近场结构(SuperRENS)薄膜样品的非线性光学性质.实验获得了其三阶非线性折射率系数随入射光功率的变化曲线.并与Au,Ag薄膜作了比较.讨论了光致非线性变化过程。结果表明,在聚焦激光作用下.AgOx超分辨近场结构薄膜样品存在一相变点.即解析出纳米Ag颗粒,满足了产生局域表面等离子体的激发和增强效应的条件。 相似文献
58.
Highly Efficient Three Primary Color Organic Single‐Crystal Light‐Emitting Devices with Balanced Carrier Injection and Transport 下载免费PDF全文
Ran Ding Jing Feng Feng‐Xi Dong Wei Zhou Yang Liu Xu‐Lin Zhang Xue‐Peng Wang Hong‐Hua Fang Bin Xu Xian‐Bin Li Hai‐Yu Wang Shu Hotta Hong‐Bo Sun 《Advanced functional materials》2017,27(13)
Organic single crystals have a great potential in the field of organic optoelectronics because of their advantages of high carrier mobility and high thermal stability. However, the application of the organic single crystals in light‐emitting devices (OLEDs) has been limited by single‐layered structure with unbalanced carrier injection and transport. Here, fabrication of a multilayered‐structure crystal‐based OLED constitutes a major step toward balanced carrier injection and transport by introducing an anodic buffer layer and electron transport layer into the device structure. Three primary color single‐crystal‐based OLEDs based on the multilayered structure and molecular doping exhibit a maximum luminance and current efficiency of 820 cd cm?2 and 0.9 cd A?1, respectively, which are the highest performance to date for organic single‐crystal‐based OLEDs. This work paves the way toward high‐performance organic optoelectronic devices based on the organic single crystals. 相似文献
59.
Since the first demonstration of light‐emitting electrochemical cells (LECs) in 1995, much effort has been made to develop this technology for display and lighting. A common LEC generally contains a single emissive layer blended with a salt, which provides mobile ions under a bias. Ions accumulated at electrodes facilitate electrochemical doping such that operation voltage is low even when employing high‐work‐function inert electrodes. The superior properties of simple device architecture, low‐voltage operation, and compatibility with inert metal electrode render LECs suitable for cost‐effective light‐emitting sources. In addition to enormous progress in developing novel emissive materials for LECs, optical engineering has been shown to improve device performance of LECs in an alternative way. Light outcoupling enhancement technologies recycle the trapped light and increase the light output from LECs. Techniques to estimate emission zone position provide a powerful tool to study carrier balance of LECs and to optimize device performance. Spectral tailoring of the output emission from LECs based on microcavity effect and localized surface plasmon resonance of metal nanoparticles improves the intrinsic emission properties of emissive materials by optical means. These reported optical techniques are overviewed in this review. 相似文献
60.