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81.
The interferometric intensity patterns from a 2D shearing interferometer are shown and discussed. The intensity patterns can be obtained in two different approaches incorporating differential and extended wavefront controlled displacements. The reliable directional sensitivity of this interferometer allows the optimization of the measurement parameters to estimate the wavefront of the intensity patterns by regularization techniques. 相似文献
82.
P. Nithiananthi 《Solid State Communications》2006,137(8):427-430
The binding energies of a hydrogenic donor both in the parabolic and non-parabolic conduction band model within the effective mass approximation have been computed for the low-dimensional semiconducting systems (LDSS) like quantum well, quantum well wire and quantum dot taking GaAs/AlxGa1−xAs systems as an example. It is observed that the effect of non-parabolicity is not effective when the system goes to lower dimensionality. The diamagnetic susceptibility of a hydrogenic donor impurity has also been computed in these LDSS in the infinite barrier model. Since no theoretical or experimental works on the diamagnetic susceptibility of LDSS are available in the literature, as a realistic case the diamagnetic susceptibility has been computed in the finite barrier model (x=0.3) for a quantum well and the results are discussed in the light of semiconductor-metal transition. 相似文献
83.
Polymethyl methacrylate (PMMA) is one of the most commonly used optical materials. However, the application of it in the area of optical communication is strongly limited by the intrinsic absorption loss of carbon-hydrogen stretching vibration. In this paper, we present a method to solve the problem by adopting the hollow-core fibers with cobweb cladding structure. The fibers use a single dielectric material and may solve the problem of structural support. Thus the feasibility of the “OmniGuide” fibers is improved, while a series of advantages of the “OmniGuide” hollow-core fiber are retained. It is promising that a fiber with low transmission loss, high bandwidth, large-core, and low costs can be designed and fabricated using PMMA. At the same time, a very broad range of the wavelengths (from visible to near infrared region, for instance, wavelengths at 0.65-1.12 μm, and even 1.30 μm, 1.54 μm and their neighbors) may be adopted for signal wavelength. 相似文献
84.
Peter Dräxler 《Journal of Pure and Applied Algebra》2002,169(1):33-42
We show that the cleaving functors introduced in [Bautista et al., Invent. Math. 81 (1985) 217] as a tool for proving infinite representation type of finite-dimensional algebras can also be used to establish controlled wildness. The main application is that an algebra is controlled wild if there is an indecomposable projective module with a Loewy factor having a homogeneous direct summand which is of length at least 3. As a second application we derive Han's covering criterion. 相似文献
85.
86.
本文定义了二阶微分方程的弱 Carathéodory解 ,在不涉及紧型条件的情形下 ,直接用迭代法证明了 Banach空间二阶非线性常微分方程两点边值问题存在唯一解 ,并给出逼近解迭代序列的误差估计 ,对周期边值问题得到类似的结果 相似文献
87.
Recursive algorithms for the computation of standard deviation and average deviation are derived and their applications in data acquisition are discussed. The relative speeds and accuracies of the two algorithms are compared for synthetic data. The performance of recursive estimation under shot and proportional noise limitations is also described. As an example of the utility of these algorithms, absorbance data with constant confidence intervals are collected regardless of incident and transmitted intensities. The desired precision is specified prior to data acquisition and used to control signal-averaging of the data in real time. 相似文献
88.
Volker Elling. 《Mathematics of Computation》2006,75(256):1721-1733
A particular case of initial data for the two-dimensional Euler equations is studied numerically. The results show that the Godunov method does not always converge to the physical solution, at least not on feasible grids. Moreover, they suggest that entropy solutions (in the weak entropy inequality sense) are not well posed.
89.
90.
Carlos Guerrero-Sanchez 《Applied Surface Science》2006,252(7):2555-2561
The application of combinatorial and high-throughput approaches in polymer research is described. An overview of the utilized synthesis robots is given, including different parallel synthesizers and a process development robot. In addition, the application of the parallel synthesis robots to reversible addition fragmentation termination (RAFT) radical polymerizations and ionic copolymerizations is overviewed. Moreover, first results concerning the process development of semi-batch free radical polymerizations are described. 相似文献