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121.
In this paper, we give a convergence theorem and error estimates for an iteration method under new Kantorovitch-Ostrowski type condition using the information of higher derivatives at initial points. Compared with the corresponding study in [3],the convergence determination is established under one global condition, instead of two , on the function.  相似文献   
122.
In this paper, the authors prove that some oscillatory singular integral operators of non-convolution type with non-polynomial phases are bounded from the Herz-type Hardy spaces to the Herz spaces and from the Hardy spaces associated with the Beurling algebras to the Beurling algebras in higher dimensions, even though it is well-known that these operators are not bounded from the Hardy space H1(Rn) into the Lebesgue spaceL1(Rn).  相似文献   
123.
The properties of the excitonic luminescence for nanocrystalline ZnO thin films are investigated by using the dependence of excitonic photoluminescence (PL) spectra on temperature. The ZnO thin films are prepared by thermal oxidation of ZnS films prepared by low-pressure metalorganic chemical vapor deposition (LP-MOCVD) technique. The X-ray diffraction (XRD) indicates that ZnO thin films have a polycrystalline hexagonal wurtzite structure with a preferred (0 0 2) orientation. A strong ultraviolet (UV) emission peak at 3.26 eV is observed, while the deep-level emission band is barely observable at room temperature. The strength of the exciton-longitudinal-optical (LO) phonon coupling is deduced from the temperature dependence of the full-width at half-maximum (FWHM) of the fundamental excitonic peak, decrease in exciton-longitudinal-optical (LO) phonon coupling strength is due to the quantum confinement effect.  相似文献   
124.
荧光波长对共焦显微镜成像特性的影响   总被引:7,自引:0,他引:7  
导出了共焦显微镜中不同荧光波长情况下的荧光功率传输函数、三维脉冲响应函数(3D-PSF)和三维光学传递函数(3D-OTF)。结果表明,不同的荧光波长对共焦显微镜的空间截止频率、分辨率、光学传递函数存在明显的影响。当激发波长与荧光波长的比值下降到一定程度时,可以看到明显的失锥现象。  相似文献   
125.
Crack initiation and stable crack growth under monotonic loading in steels has been studied using an elastic-plastic finite element analysis. The fracture criterion used for crack initiation and stable crack growth was the critical strain energy density. In addition the shift core method for the analysis of crack extension was used. In the shift core modelling method, crack advance is simulated by moving the coordinates of the core region which surrounds the crack tip, to obtain the stiffness reduction. Simultaneously the core itself geometrically undergoes a simple rigid-body motion or translation during the crack extension. The analytically calculated and experimentally measured load for crack initiation and the subsequent stable crack growth agreed well.  相似文献   
126.
Patterned uniformly (100)-orientated silicon nanocrystallite (SiNC) films were fabricated based on hydrogen ion implantation technique and typical electrochemical anodic etching method. The surface morphology and microstructure characteristics of the films were characterized by scanning electron microscopy, transmission electron microscopy, X-ray diffraction, and atomic force microscopy. The efficient field emission with low turn-on field of about 3.2 V/μm at current density of 0.1 μA/cm2 was obtained. The emission current density from the SiNC films reached 1 mA/cm2 under a bias field of about 11 V/μm. The experimental results demonstrate that the SiNC films have great potential applications for flat panel displays.  相似文献   
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129.
This paper introduces a profile empirical likelihood and a profile conditionally empirical likelihood to estimate the parameter of interest in the presence of nuisance parameters respectively for the parametric and semiparametric models. It is proven that these methods propose some efficient estimators of parameters of interest in the sense of least-favorable efficiency. Particularly, for the decomposable semiparametric models, an explicit representation for the estimator of parameter of interest is derived from the proposed nonparametric method. These new estimations are different from and more efficient than the existing estimations. Some examples and simulation studies are given to illustrate the theoretical results. The first author is supported by NNSF projects (10371059 and 10171051) of China. The second author is supported by a grant from The Research Grants Council of the Hong Kong Special Administrative Region, China (#HKU7060/04P). The third author is supported by the University Research Committee of the University of Hong Kong and a grant from the Research Grants Council of the Hong Kong Special Administrative Region, China (Project No. HKU7323/01M).  相似文献   
130.
HL-1装置中LHCD和等离子体参数的关系   总被引:1,自引:1,他引:0  
本文研究了在HL-1托卡马克的不同放电阶段的低混杂波驱动特性。给出了驱动电流及驱动效率和等离子体参数,如电子平均密度ne、等离子体电流Ip及纵向磁场的关系。也给出和分析了波驱动和入射波功率的关系。在放电平段,对正反向驱动效率进行了研究和比较。  相似文献   
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