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111.
Jianfeng Jia Kai Huang Qingtao Pan Deyan He 《Journal of Sol-Gel Science and Technology》2007,42(1):9-12
The leakage behavior and dielectric property of BST80/MgO heterostructured thin films deposited on LaNiO3 (LNO)/Si substrates by sol-gel were investigated. The dielectric constant and the leakage current are modified by MgO insertion.
The dramatic reduction in the leakage current effectively increased the charge retention of the capacitors consisted of heterostructured
thin films as compared to the pure BST films. The significant reduction in the leakage current can be attributed to the minute
solid solubility of MgO in the BST lattice and the potential barrier built in the interface between BST and MgO layers in
the heterostructured thin films. 相似文献
112.
简要介绍了同步辐射的原理、装置和特点,综述了它在高分子取向态结晶、熔化、相分离、相转变和银纹产生等高分子研究方面的应用。 相似文献
113.
非晶态聚对苯二甲酸乙二酯膜应力屈服机制的示差扫描量热研究 总被引:1,自引:2,他引:1
采用示差扫描量热法、应力应变测量研究了物理老化对非晶态聚对苯二甲酸乙二酯(PET)膜单轴拉伸过程中应力屈服行为的影响.结果表明,非晶高聚物经物理老化后屈服应力,应力屈服峰及热焓吸热峰均增大;屈服前后的DSC结果表明,经过屈服点后试样热焓吸热峰消失,屈服后的试样经物理老化后,应力屈服峰又再现.从凝聚缠结的观点解释了非晶高聚物物理老化和应力屈服的本质. 相似文献
114.
115.
We present ab initio calculation within the framework of the density‐functional theory (DFT) on band structure and vibrational properties of bulk V2O5. The structure of V2O5 comes from optimization of the experimental data with lattice parameters fixed. The band structure of the optimized structure has been calculated, and the result fits the experimental data very well and also gives similar results as those calculated by other methods. The phonon eigenwavenumbers of the Γ‐ point of V2O5 bulk have been calculated ab initio in density‐functional perturbation theory (DFPT). The calculated vibrational wavenumbers are in good agreement with observed infrared and Raman wavenumbers, and the predictive full phonon dispersion of bulk V2O5 has also been obtained. Further we calculated the Raman spectrum of vanadium pentoxide (V2O5) powder sample using the obtained Raman susceptibility. Calculated and measured intensities show overall good agreement. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
116.
Yongsheng Zhang Ke Yu Deyan Peng Hongmei Hu Wei Bai Ziqiang Zhu 《Applied Surface Science》2006,253(2):792-796
A simple and reliable method has been developed for synthesizing finely patterned tin dioxide (SnO2) nanostructure arrays on silicon substrates. A patterned Au catalyst film was prepared on the silicon wafer by radio frequency (RF) magnetron sputtering and photolithographic patterning processes. The patterned SnO2 nanostructures arrays, a unit area is of ∼500 μm × 200 μm, were synthesized via vapor phase transport method. The surface morphology and composition of the as-synthesized SnO2 nanostructures were characterized by means of scanning electron microscopy (SEM) and X-ray diffraction (XRD). The mechanism of formation of SnO2 nanostructures was also discussed. The measurement of field emission (FE) revealed that the as-synthesized SnO2 nanorods, nanowires and nanoparticles arrays have a lower turn-on field of 2.6, 3.2 and 3.9 V/μm, respectively, at the current density of 0.1 μA/cm2. This approach must have a wide variety of applications such as fabrications of micro-optical components and micropatterned oxide thin films used in FE-based flat panel displays, sensor arrays and so on. 相似文献
117.
Xianju Zhou Lihui Weng Jianming Zhang Deyan Shen Jian Xu 《Journal of Polymer Science.Polymer Physics》2003,41(19):2290-2295
A novel transmittance change of poly(acrylamide‐co‐acrylic acid) hydrogel in a DC electric field was observed. Transmittance of a specimen increased when the electric field was on and decreased by removing the electric force. In certain cases, the sample was able to switch from white opaque to colorless transparent. The rate and extent of the transition depended on the applied electric potential, ambient temperature, and composition of the specimen. These observations are closely related to the dissociation of hydrogen bonding in the network induced by an external electric field. © 2003 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 41: 2290–2295, 2003 相似文献
118.
尼龙1010的远红外光谱研究 总被引:1,自引:0,他引:1
本文研究了结晶程度不同的尼龙1010远红外光谱的差异,对其谱带进行了经验归属。用分峰方法详细地研究了尼龙1010结晶程度的变化对其远红外谱带的位置、宽度和强度的影响。并对由不同退火方式得到的结晶样品的远红外光谱作了比较,由此证明了两者的结晶结构有所差异。 相似文献
119.
在研究了激光光束质量因子M^2理论及测量技术基础上,作者提出了一种新的用干涉测量光束质量因子M^2的理论,技术与方法。文中概述了该技术的理论基础、实验结果及误差分析。结果表明,该方法具有精度高,适用性强,测量简便等优点,有可能进一步仪器化并推广应用。 相似文献
120.
Heinrich Stamerjohanns Michael Kohlhase Deyan Ginev Catalin David Bruce Miller 《Mathematics in Computer Science》2010,3(3):299-307
We describe an experiment transforming large collections of L a TEX documents to more machine-understandable representations. Concretely, we are translating the collection of scientific publications of the Cornell e-Print Archive (arχiv) using LaTeXML, a L a TEX to XML converter currently under development. While the long-term goal is a large body of scientific documents available for semantic analysis, search indexing and other experimentation, the immediate goals are tools for creating such corpora. The first task of our arXMLiv project is to develop LaTeXML bindings for the (thousands of) L a TEX classes and packages used in the arχiv collection, as well as methods for coping with the eccentricities that TEX encourages. We have created a distributed build system that runs LaTeXML over the collection, in part or entirely, while collecting statistics about missing bindings and other errors. This guides debugging and development efforts, leading to iterative improvements in both the tools and the quality of the converted corpus. The build system thus serves as both a production conversion engine and software test harness. We have now processed the complete arχiv collection through 2006 consisting of more than 400,000 documents (a complete run is a processor-year-size undertaking), continuously improving our success rate. We are now able to convert more than 90% of these documents to XHTML+MathML. We consider over 60% to be successes, converted with no or minor warnings. While the remaining 30% can also be converted, their quality is doubtful, due to unsupported macros or conversion errors. 相似文献