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101.
Cu(In, Ga)Se2 (CIGS) thin films were fabricated by ion beam sputtering deposition from a single quaternary target at different substrate temperatures (T sub). The thin films were characterized with X-ray diffractometry, scanning electron microscopy, energy-dispersive X-ray spectroscopy and four-point probe technique to study the microstructures, surface morphology, composition and electrical properties, respectively. The results show that the films grown above 400?°C are of chalcopyrite structure. Cu(In0.7Ga0.3)Se2 thin film was obtained when T sub is 550?°C. The Cu and Se atomic percentage when T sub is above 500?°C is higher than when T sub is below 500?°C. With the increase in T sub, the surfaces morphology of the films is denser and the resistivity of the films decreases.  相似文献   
102.
综述了制备淀粉接枝共聚物过程中,淀粉种类、其是否糊化,引发剂及单体的选择及其用量,以及反应温度和反应时间等因素对制备淀粉接枝共聚物的影响,指出应根据所需产物性能要求,综合考虑各方面因素的影响.并提出开发新的廉价而高效的引发剂成为市场所需,淀粉制备工艺的简约处理以及性能优良的淀粉衍生物产品的开发值得人们进一步的深入探讨.  相似文献   
103.
Rare earth zirconates (Ln2Zr2O7, Ln = La, Nd, Sm, and Gd) with pyrochlore structure were prepared by hydrothermal method with polyethylene glycol as surfactant. X-ray diffraction, thermogravimetric analysis/differential scanning calorimetry, Fourier transform infrared spectroscopy, Raman spectroscopy, and field emission scanning electron microscopy were utilized to characterize the phase structure, thermal decomposition, and morphology of the products. Qualitative analysis indicates that the as-prepared zirconates are pyrochlore-type structures. The specific surface area, lattice parameter, and average crystallite size of the as-prepared products are closely related to the ionic radius. The activation energy of crystal growth shows an increasing trend with the decrease in ionic radii. The sintering behavior of compacted body was also investigated, revealing that the sintering-resistance properties of Ln2Zr2O7 are descending as the order of La2Zr2O7, Nd2Zr2O7, Sm2Zr2O7, and Gd2Zr2O7.  相似文献   
104.
本拟设计了一种用于汽车挡风玻璃上的自动雨点检测器及刮雨器控制装置,其原理利用了挡风玻璃中的光波导作用,并经模拟实验证实此方案可行。  相似文献   
105.
106.
采用离子束溅射镀膜装置制备了一种新的材料组合Si/C多层膜 ,用于 30 4nm波段的正入射多层膜反射镜。并用软X射线反射率计测得其反射比最大值为 0 14。有效地抑制了 15 0nm处的二级衍射峰。  相似文献   
107.
V-doped TiO2 with V/Ti ratio of 1–5% has been synthesized by hydrothermal method and then characterized by XRD, TEM, BET specific surface area, XPS and UV–vis. absorption spectra. The photocatalytic activity of the as-synthesized samples was investigated by the degradation of methylene blue in aqueous solution under visible light irradiation. Density functional theory (DFT) based calculations were performed to investigate the mechanism of band gap narrowing, the shift of light absorption edge, the location of V in the TiO2 lattice and the variation in electronic and optical properties of TiO2 with the increase of V doping concentration. Irrespective of the V doping concentration, TEM images indicate that all the doped samples were composed of equiaxed spherical anatase TiO2 particles with good crystallinity and uniform particle size distribution. Both the experimental results from XPS survey and the theoretical calculation argue that the doped V replaces the lattice Ti and form substitutional impurity. The visible light absorption can be optimized by adjusting the V doping concentration. Among the doped samples with different V doping concentrations, the sample with V/Ti ratio of 2% depicts better visible light photocatalytic activity due to the enhanced visible light absorption and improved separation of electron–hole pairs.  相似文献   
108.
利用SEM拉伸台,研究了Ti-33Al-3Cr-0.5Mo合金的室温拉伸断裂动态过程。试验结果表明,具有全层片状显微组织的TiAl合金室温断裂韧性较高,归因于合金拉伸过程中裂纹尖端发生分叉致使应力松弛而使裂纹钝化;在变形过程中,主裂纹尖端附近的微裂纹之间形成剪切韧带,剪切韧带韧化是TiAl合金的一种韧化机理。  相似文献   
109.
基于小波神经网络的煤矿瓦斯涌出量预测   总被引:4,自引:0,他引:4  
针对影响瓦斯涌出量的因素复杂多样化以及各因素之间的非线性问题,综合利用神经网络的自学习能力和小波变换的局部化性质,采用了一种基于黄金分割原理获得隐含层节点数的寻优算法,结合MATLAB强大的运算功能,建立了基于小波神经网络的煤矿瓦斯涌出量预测模型.仿真结果表明整个系统具有较强的逼近和容错能力,以及较快的收敛速度和良好的预报效果.  相似文献   
110.
Colibacillosis is an acute and chronic avian disease caused by avian pathogenic E. coli (APEC). Previous studies have demonstrated that RIP2 plays a significant role in APEC infection. Moreover, increasing evidence indicates that microRNAs (miRNAs) are involved in host–pathogen interactions and the immune response. However, the role of miRNAs in the host against APEC infection remains unclear. Herein, we attempted to reveal new miRNAs potentially involved in the regulation of the immune and inflammatory response against APEC infection, with a particular focus on those possibly correlated with RIP2 expression, via miRNA-seq, RT-qPCR, Western blotting, dual-luciferase reporter assay, and CCK-8. The results showed that a total of 93 and 148 differentially expressed (DE) miRNAs were identified in the knockdown of RIP2 cells following APEC infection (shRIP2+APEC) vs. knockdown of RIP2 cells (shRIP2) and shRIP2 vs. wild-type cells (WT), respectively. Among those identified DE miRNAs, the biological function of gga-miR-455-5p was investigated. It was found that gga-miR-455-5p regulated by RIP2 was involved in the immune and inflammatory response against APEC infection via targeting of IRF2 to modulate the expression of type I interferons. Additionally, RIP2 could directly regulate the production of the type I interferons. Altogether, these findings highlighted the crucial role of miRNAs, especially gga-miR-455-5p, in host defense against APEC infection.  相似文献   
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