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51.
Tsuchiya T Imai H Miyoshi S Glans PA Guo J Yamaguchi S 《Physical chemistry chemical physics : PCCP》2011,13(38):17013-17018
The electronic structure and modification of the local interatomic structure of a reactive sputtered amorphous tantalum oxide (a-TaO(x)) thin film with the variation of oxygen nonstoichiometry, x in a-TaO(x) have been investigated by X-ray absorption spectroscopy (XAS), X-ray photoemission spectroscopy (XPS), Raman scattering spectroscopy, and Rutherford back scattering spectroscopy. A parallel chemical shift of Ta4f(7/2) and O1s core levels observed with the variation of x indicates the Fermi level shift by reduction and oxidation in the framework of the rigid band model. Extended X-ray absorption fine structure (EXAFS) suggests both the increase of average coordination number of the first Ta-O shell in polyhedra and a considerable reduction of the average Ta-O bond length with the increase of x. The relative intensity of Raman shift peaks at 670 cm(-1) and 815 cm(-1), corresponding to Ta-O stretching of TaO(6) octahedra and TaO(5) probably with a pyramidal form, respectively, drastically changes between x = 2.47 to 1.86, suggesting the change in the predominant polyhedron from TaO(6) to TaO(5) with a modification in multiplicity of oxygen by the reorganization of the polyhedral network. 相似文献
52.
A tunable multi-function broadband splitter consisted of a silver film, Kerr medium and a silver grating sandwiched between linear dielectrics waveguides is proposed and numerically investigated. This splitter can realize the functions of the beam splitter, the polarization splitter and wavelength beam splitter. This surface plasmon based device provides a unique approach for polarization sensitive manipulation of light in an integrated circuit and will be essential for future classical and quantum information processes. 相似文献
53.
Hongxin Wang Anthony T. Young Jinghua Guo Stephen P. Cramer Stephan Friedrich Artur Braun Weiwei Gu 《Journal of synchrotron radiation》2013,20(4):614-619
X‐ray absorption and scattering spectroscopies involving the 3d transition‐metal K‐ and L‐edges have a long history in studying inorganic and bioinorganic molecules. However, there have been very few studies using the M‐edges, which are below 100 eV. Synchrotron‐based X‐ray sources can have higher energy resolution at M‐edges. M‐edge X‐ray absorption spectroscopy (XAS) and resonant inelastic X‐ray scattering (RIXS) could therefore provide complementary information to K‐ and L‐edge spectroscopies. In this study, M2,3‐edge XAS on several Co, Ni and Cu complexes are measured and their spectral information, such as chemical shifts and covalency effects, are analyzed and discussed. In addition, M2,3‐edge RIXS on NiO, NiF2 and two other covalent complexes have been performed and different d–d transition patterns have been observed. Although still preliminary, this work on 3d metal complexes demonstrates the potential to use M‐edge XAS and RIXS on more complicated 3d metal complexes in the future. The potential for using high‐sensitivity and high‐resolution superconducting tunnel junction X‐ray detectors below 100 eV is also illustrated and discussed. 相似文献
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55.
Zhirong Xin Yongtao Ding Jinghua Yin Zhuo Ke Xiaodong Xu Ying Gao Giovanna Costa 《Journal of Polymer Science.Polymer Physics》2005,43(3):314-322
Three nonionic surfactants, S1, S2, and S3 and their acrylates, AS1, AS2, and AS3, were synthesized with poly(ethylene oxide) and diols such as glycol, 1,6‐hexanediol, and 1,10‐decanediol as the main starting materials. Their chemical structures were characterized by means of Fourier transform infrared (FTIR) spectroscopy and 1H NMR. The surface activity and surface tension (γ) of S1, S2, and S3 were evaluated by a drop weight method. The surface tension was found to decrease with the length of the lipophilic spacer in the molecular chains (γS1 < γS2 < γS3). AS1, AS2, and AS3 were adopted as functionalizing monomers and grafted onto linear low density polyethylene (LLDPE) with a melt reactive extrusion procedure. The graft degrees of LLDPE were determined by FTIR. Three grafted LLDPE samples with grafting degrees of 1.16% (AS1), 0.82% (AS2), and 0.71% (AS3) were prepared. Thermal and rheological properties of grafted LLDPE samples were studied with differential scanning calorimetry and a rotational rheometer. Crystallization rates of grafted LLDPE were faster than that of plain LLDPE at a given crystallization temperature because graft chains could act as nucleating agents. The isothermal crystallization behavior of grafted LLDPE was in accordance with the Avrami model only in the first stage, and deviated from the model with an increase in the crystallization time. Shear thinning at high shear rates and shear thickening at low shear rates were observed for the grafted LLDPE. © 2004 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 43: 314–322, 2005 相似文献
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57.
引入了正切函数作为非线性光-电流关系函数,借地速率方程,建立了光学双稳半导体激光器的理论模型。对器件本身进行了理论分析,讨论了器件的主要特性,给出了数值分析结果,提出了器件性能改进方法。 相似文献
58.
Summary. In this paper we derive an error bound for the large time step, i.e. large Courant number, version of the Glimm scheme when used for the approximation
of solutions to a genuinely nonlinear, i.e. convex, scalar conservation law for a generic class of piecewise constant data.
We show that the error is bounded by for Courant numbers up to 1. The order of the error is the same as that given by Hoff and Smoller [5] in 1985 for the Glimm
scheme under the restriction of Courant numbers up to 1/2.
Received April 10, 2000 / Revised version received January 16, 2001 / Published online September 19, 2001 相似文献
59.
以强激光应用在化学工程中所遇到的物理问题为背景,研究介质的热透镜效应、吸收强弱、吸收饱和程度以及介质的流动等因素对激光传播的影响。根据一组简化模型,提出了描述光场行为的方程组,给出了不同情况下介质的温度分布情况、光线在介质中的变化行为以及激光光强的分布化情况。所得结果,对光化学工程设计有一定的参考价值。 相似文献
60.
A new acetogenin, polyporolide (1), was isolated from the mycelial solid cultures of a Polyporus basidiomycete. Its structure was elucidated as 4-hydroxy-5-(1-hydroxyhexyl)-dihydrofuran-2-one by spectroscopic methods. Its toxicity to brine shrimps was assessed. 相似文献