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排序方式: 共有101条查询结果,搜索用时 31 毫秒
31.
In this work, we have investigated the effect of HCl concentration and particle packing on the sintering behavior of 8 mol% yttria-stabilized-zirconia (8YSZ) deposits. 8YSZ deposits were fabricated by electrophoretic deposition (EPD). For 8YSZ coatings, it was found that the concentration of HCl in the EPD suspension significantly influences the neck size to grain size ratio. High neck size to grain size ratio (0.8 ± 0.03) was found in the sintered 0.8 HCl coating. The grain growth was observed to depend on the initial particle packing in the green coating. The effect of chloride ions on the grain and neck growth as well as elemental segregation within the 8YSZ is investigated using photoelectron spectroscopy (XPS) which confirmed the presence of chloride ions in green and sintered 8YSZ coatings. This was later confirmed using high-resolution transmission electron microscopy (HRTEM) and thermal analysis techniques. It was found that the presence of chloride ions induced an increase in the oxygen vacancy concentration at the grain boundaries. High oxygen vacancy concentration in the grain boundaries could promote neck growth of 8YSZ.  相似文献   
32.
赵源 《光电子.激光》2010,(11):1650-1652,1667
通过仿真研究了10和40Gb/s RZ-DPSK电预失真(EPD)系统中的自相位调制(SPM)和交叉相位调制(XPM)等非线性效应。EPD系统中的非线性效应比光色散补偿(ODC)中的大,但在不同比特率下非线性效应不同。对800km标准单模光纤(SSMF)传输的仿真的结果表明:单信道传输时受到SPM影响,比特率为10Gb/s的EPD系统的非线性阈值比ODC系统的小6dBm以上,而当比特率为40Gb/s时的EPD系统非线性阈值只比ODC系统小2dBm。波分复用(WDM)系统中受到SPM和XPM的影响,比特率为10Gb/s的EPD系统的非线性阈值比ODC系统的小6dBm,而比特率为40Gb/s时的EPD系统非线性阈值比ODC系统的小2dBm。研究结果表明,当比特率升高时,EPD系统的非线性效应减弱。  相似文献   
33.
The aim of this study was to understand to what extent people can read e‐paper devices under various conditions of ambient illuminance that can occur indoors. In this study, 110 young to elderly subjects participated in an experiment to evaluate the effects of 14 different levels of ambient lighting on their reading from three different electronic devises and paper text. The participants were asked to undergo a timed read task and then to evaluate the readability of two eReader devices (a regular electronic display and one with a front light) in comparison with a backlit liquid crystal device and conventional paper text. The results indicated that backlit and front lit devices are easier to read at less than 200 lx and the reflective device is easier to read at levels above 500 lx.  相似文献   
34.
电泳沉积制备平行栅碳纳米管场发射阴极的研究   总被引:2,自引:0,他引:2  
利用磁控溅射、光刻、湿法刻蚀和电泳技术在玻璃基片上成功制备平行栅场发射阴极阵列,用光学显微镜、场发射扫描电镜和拉曼光谱观察了碳纳米管的形貌和结构,并测试所制备的平行栅碳纳米管阴极的场发射性能.光学显微镜和场发射电子显微镜测试表明,平行栅结构阴极和栅极交替地分布,同一个平面内,CNTs有选择性地沉积在平行栅结构中的阴极表...  相似文献   
35.
赵博选  王琦 《电视技术》2014,38(4):43-51
分析了近几年柔性显示技术的市场规模,并对未来市场做了展望及预测。全面地研究、分析、总结了主流的八种柔性显示技术(有机电致发光显示、电泳显示、TFT-LCD显示、无机电致发光显示、电子粉流体显示、干涉调制显示、电致变色显示、等离子管阵列显示等)的显示原理、研发现状、国内外主要研发机构及相关产品/样品模型,提出了对应柔性显示技术未来研发方向及思路。并对另外两种柔性显示技术(光子晶体显示及电润湿显示)做了技术原理、研发现状及研发方向等的研究与分析。最后对柔性显示技术研发中的共性焦点问题和未来关键研发思路及方向做了分析与论述。  相似文献   
36.
将无源元件及IC等全部埋入基板内部的三维封装,不仅能提高电子设备的整体性能,有利于轻薄短小化,而且 由于钎焊连接部位减少,可提高可靠性并能有效降低封装的总价格。  相似文献   
37.
报道了用 MBE的方法 ,在 Zn Cd Te衬底上制备 Hg Cd Te薄膜的位错密度研究结果。研究发现Hg Cd Te材料的位错密度与 Zn Cd Te衬底的表面晶体损伤、Hg Cd Te生长条件以及材料组分密切相关。通过衬底制备以及生长条件的优化 ,在 Zn Cd Te衬底上生长的长波 Hg Cd Te材料 EPD平均值达到 4.2× 1 0 5cm- 2 ,标准差为 3 .5× 1 0 5cm- 2 ,接近 Zn Cd Te衬底的位错极限。可重复性良好 ,材料位错合格率为 73 .7%。可以满足高性能Hg Cd Te焦平面探测器对材料位错密度的要求  相似文献   
38.
针对目前电子纸驱动依赖专用驱动芯片的现状,从ED060SC4型电子纸的驱动时序研究以及分析电子纸显示驱动原理出发,提出了基于FPGA为核心的电子纸驱动接口系统方案。系统的控制和驱动集成于FPGA中,首次采用该设计方案实现了16级灰度电子纸图像显示。提出不依赖驱动芯片的接口方案对今后国内电子纸驱动的进一步研究及产业化有着积极意义。  相似文献   
39.
Energy efficiency, which consists of using less energy or improving the level of service to energy consumers, refers to an effective way to provide overall energy. But its increasing pressure on the energy sector to control greenhouse gases and to reduce CO2 emissions forced the power system operators to consider the emission problem as a consequential matter besides the economic problems. The economic power dispatch problem has, therefore, become a multi-objective optimization problem. Fuel cost, pollutant emissions, and system loss should be minimized simultaneously while satisfying certain system constraints. To achieve a good design with different solutions in a multi-objective optimization problem, fuel cost and pollutant emissions are converted into single optimization problem by introducing penalty factor. Now the power dispatch is formulated into a bi-objective optimization problem, two objectives with two algorithms, firefly algorithm for optimization the fuel cost, pollutant emissions and the real genetic algorithm for minimization of the transmission losses. In this paper the new approach (firefly algorithm-real genetic algorithm, FFA-RGA) has been applied to the standard IEEE 30-bus 6-generator. The effectiveness of the proposed approach is demonstrated by comparing its performance with other evolutionary multi-objective optimization algorithms. Simulation results show the validity and feasibility of the proposed method.  相似文献   
40.
This research demonstrates a novel one-step electrochemical method to fabricate thick bilayer coatings on magnesium alloy in acid phosphate electrolyte containing aniline monomer and styrene-acrylic emulsion (SAE) with pulsed DC voltage, The morphologies, XRD and FTIR results show that the bilayer coating consists of an inner oxide layer and an outer polyaniline (PANI)/SAE composite layer, It is believed that the bilayered structure achieved results from a hybrid process combining electropoly-merization (EPM) of aniiine, electrophoretic deposition (EPD) of SAE and plasma electrolyte oxidation (PEO) of magnesium alloy substrate. Electrochemical corrosion tests indicate that the bilayer coating can provide superior corrosion protection to the magnesium alloy substrate in 3.5 wt.% NaCl solution.  相似文献   
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