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31.
Image analysis is an important tool for characterizing nano/micro network structures. To understand the connection, organization and proper alignment of network structures, the knowledge of the segments that represent the materials inside the image is very necessary. Image segmentation is generally carried out using statistical methods. In this study, we developed a simple and reliable masking method that improves the performance of the indicator kriging method by using entropy. This method selectively chooses important pixels in an image (optical or electron microscopy image) depending on the degree of information required to assist the thresholding step. Reasonable threshold values can be obtained by selectively choosing important pixels in a complex network image composed of extremely large numbers of thin and narrow objects. Thus, the overall image segmentation can be improved as the number of disconnected objects in the network is minimized. Moreover, we also proposed a new method for analyzing high‐pixel resolution images on a large scale and optimized the time‐consuming steps such as covariance estimation of low‐pixel resolution image, which is rescaled by performing the affine transformation on high‐pixel resolution images. Herein, image segmentation is executed in the original high‐pixel resolution image. This entropy‐based masking method of low‐pixel resolution significantly decreases the analysis time without sacrificing accuracy. 相似文献
32.
将相反电荷的纳米Au和纳米CdTe通过静电作用得到纳米复合Au/CdTe粒子。在水溶液中分别用二甲氨基吡啶和巯基丙酸稳定纳米Au和CdTe粒子,使其表面分别带有正电荷与负电荷。Au/CdTe纳米复合材料的表面等离子体吸收光谱随着Au含量的增加而红移,表明纳米复合Au/CdTe粒子的长大是由于配位形成而引起的。纳米Au和纳米CdTe的比影响纳米复合Au/CdTe粒子的结构。复合纳米Au/CdTe粒子的尺寸和形状是影响金属/半导体纳米复合材料性能的重要参数。用小角X射线散射技术、透射电子显微镜、循环伏安法和X射线光电子能谱来表征纳米复合Au/CdTe粒子。 相似文献
33.
The hydrodenitrogenation, hydrodesulfurization and hydrocracking of solvent refined coals and lignites was accomplished with catalysts comprising high surface area, large pore diameter bases impregnated with MoO3,CoOand WO3. The most effective catalysts were those which performed well in hydrodenitrogenating nitrocellulose. This indicates that most of the pore diameter is consistently large enough to accommodate molecules of the size of liquified coal and lignite. 相似文献
34.
Construction methods are presented that generate Hermite interpolation quaternion curves on SO(3). Two circular curves C1(t) and C2(t), 0 ≤ t ≤ 1, are generated that interpolate two orientations q1 and q2, and have boundary angular velocities: C1′(0) = ω1 and C2′(1) = ω2, respectively. They are smoothly blended together on SO(3) to generate a Hermite quaternion curve Q(t) ∈ SO(3), 0 ≤ t ≤ 1, which satisfies the boundary conditions: Q(0) = q1, Q(1) = 2, Q′(0) = ω1, and Q′ (1) = ω2. 相似文献
35.
对Al-Cu合金进行析出强化和人工时效处理以获得优异的力学性能,如高的强度、好的韧性。其热处理工艺条件为:510~530℃固溶处理2h;60℃水淬;160~190℃人工时效2~8h。采用光学显微镜、扫描电镜、能谱分析、透射电镜和拉伸实验对经固溶和人工时效处理的Al-Cu合金的组织和力学性能进行表征。固溶处理实验结果表明,Al-Cu合金的力学性能随着固溶处理温度的升高先增加,然后降低。这是由于Al-Cu合金的残余相逐渐溶解进入基体中,从而导致析出相的数量和再结晶晶粒尺寸不断增加。相较于固溶处理温度,固溶处理时间对Al-Cu合金的影响较小。人工时效处理实验结果表明,合金经180℃时效8h,可以获得最大的拉伸强度。合金的最大拉伸强度和屈服强度随着时效时间的延长和温度的升高而升高。 相似文献
36.
Multichip on Aluminum Metal Plate(MOAMP) technology with simple structure and low thermal resistance is developed for effective heat removal of Light Emitting Diode(LED) p-n junction and LED lighting module to have high reliability. The thermal resistance of LED modules was numerical and experimental. Thermal resistance from the junction to aluminum metal plate, considering input power of LED module using MOAMP technology, is 3.02 K/W, 3.23 K/W for the measured and calculated, respectively. We expect that the reported MOAMP technology with low thermal resistance will be a promising solution for high power LED lighting modules. 相似文献
37.
韩国泡菜的制作工艺及营养价值 总被引:1,自引:0,他引:1
泡菜是韩国的传统食品,它是以蔬菜为主料,使用盐、姜、蒜、辣椒、糖、酱等多种调料,以湿态发酵方式加工制成的浸制食品。因其具有丰富的营养价值和多种保健功能,已备受世界人民的青睐。 相似文献
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39.
ROBERT H. KADLEC DAVID E. HAMMER IN-SIK NAM JAMES O. WILKES 《Chemical Engineering Communications》2013,200(1-6):331-344
An experimental study on mixing, degree of suspension and power consumption in solid-liquid suspensions was done. A system similar to those found in anaerobic fermentation processes of animal manures was used, and an existing mixing equipment was adapted for the study. Power consumption and degree of suspension for both mechanical mixing and mixing by gas was determined. The influence of variables such as geometry, solids concentration, stirrer velocity, and gas velocity was studied, discussed, and compared to data from the literature. Best results were obtained for gas mixing, the power consumption being about one fourth of that required by mechanical agitation. Finally, extended correlations relating Power and Reynolds numbers for mechanical mixing and mixing by gas are proposed. 相似文献
40.
Conversion efficiencies of 11.5-12% have been obtained for solar cells with an active layer epitaxially grown on upgraded metallurgical grade silicon substrates made by industry. An epilayer thickness of 30 μm was shown to be sufficient if the substrate doping is much larger than the epilayer doping. Spectral response measurements, fitted to simple models, showed that: ? the electron diffusion length reached 120 μm in the epilayer, ? a back surface field was efficient in increasing collection efficiency, ? Optical path enhancement due to texturisation decreased absorption losses. These results were confirmed by modeling of the short circuit current and open circuit voltage of the cells. Economic viability is discussed. The results can also be used to increase the efficiency of conventional solar cells built on thin wafers (< 150μm). 相似文献