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991.
Super-hydrophilic properties of TiO2-DLC nanocomposite films fabricated by the simple electrochemical process 总被引:1,自引:0,他引:1
Anatase TiO2 nanoparticles incorporated DLC films were successfully deposited on single crystalline silicon substrates by the electrolysis of TiO2-methanol solution under ambient atmospheric pressure and low temperature. Anatase TiO2 nanoparticles were embedded into amorphous carbon matrix, forming the typical nanocrystalline/amorphous nanocomposite films, confirmed by transmission electron microscopy (TEM). TiO2 incorporation effectively increased the sp3-hybridized carbon concentration in the composite film, and further regulated the microstructure and surface morphology. Furthermore, the static contact testing completely displayed, TiO2 incorporation got the composite films super-hydrophilic, which fundamentally improved the wetting ability of DLC film. 相似文献
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The spatial structures of magnetic Co nanowire array embedded in anodic aluminium membranes were investigated by grazing incidence small angle X-ray scattering (GISAXS) and conventional small angle X-ray scattering (SAXS) techniques. Compared with SEM observation, the GISAXS and SAXS measurements can get more overall structural information in a large-area scale. In this study, the two-dimensional GISAXS pattern was well reconstructed by using the IsGISAXS program. The results demonstrate that the hexagonal lattice formed by the Co nanowires is distorted (a ≈ 105 nm, b ≈ 95 nm). These Co nanowires are isolated into many structure domains with different orientations with a size of about 2 μm. The SAXS results have also confirmed that the nanopore structures in the AAM can be retained after depositing Co nanowires although the Co nanowires can not completely but only just fill up the nanopores. These results are helpful for understanding the global structure of the Co nanowire array. 相似文献
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This study proposes an expectation–maximization (EM)-based curve evolution algorithm for segmentation of magnetic resonance brain images. In the proposed algorithm, the evolution curve is constrained not only by a shape-based statistical model but also by a hidden variable model from image observation. The hidden variable model herein is defined by the local voxel labeling, which is unknown and estimated by the expected likelihood function derived from the image data and prior anatomical knowledge. In the M-step, the shapes of the structures are estimated jointly by encoding the hidden variable model and the statistical prior model obtained from the training stage. In the E-step, the expected observation likelihood and the prior distribution of the hidden variables are estimated. In experiments, the proposed automatic segmentation algorithm is applied to multiple gray nuclei structures such as caudate, putamens and thalamus of three-dimensional magnetic resonance imaging in volunteers and patients. As for the robustness and accuracy of the segmentation algorithm, the results of the proposed EM-joint shape-based algorithm outperformed those obtained using the statistical shape model-based techniques in the same framework and a current state-of-the-art region competition level set method. 相似文献
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利用基尔霍夫衍射公式通过数值计算绘制出理想狭缝在不同区域的衍射光强分布,并与菲涅耳衍射公式及夫朗禾费衍射公式的计算的结果比较,对基尔霍夫衍射公式、菲涅尔衍射公式和夫朗禾费衍射公式的适用范围做了详细的讨论. 相似文献
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利用单调迭代法、数学归纳法以及序差距的性质,在半序Banach空间中探究不具有紧性、连续性以及任何凹凸性的单调算子不动点存在以及惟一性问题,得出其新不动点定理,这些结果对相关结论进行了推广,使其适用范围更广,同时将该结论应用于求解Volterra型积分方程组问题中. 相似文献
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Wang et al. (J Operat Res Soc 62: 1898–1902, 2011) studied the m identical parallel-machine and unrelated parallel-machine scheduling with a deteriorating maintenance activity to minimize the total completion time. They showed that each problem can be solved in O(n 2m+3) time, where n is the number of jobs. In this note, we discuss the unrelated parallel-machine setting and show that the problem can be optimally solved by a lower order algorithm. 相似文献