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151.
Summary. We analyze V–cycle multigrid algorithms for a class of perturbed problems whose perturbation in the bilinear form preserves the convergence
properties of the multigrid algorithm of the original problem. As an application, we study the convergence of multigrid algorithms
for a covolume method or a vertex–centered finite volume element method for variable coefficient elliptic problems on polygonal
domains. As in standard finite element methods, the V–cycle algorithm with one pre-smoothing converges with a rate independent of the number of levels. Various types of smoothers
including point or line Jacobi, and Gauss-Seidel relaxation are considered.
Received August 19, 1999 / Revised version received July 10, 2000 / Published online June 7, 2001 相似文献
152.
Two novel systems are proposed to perform the electro-optic (EO) mapping of the electric-field strength close to electrode structure using CW laser diodes. By these systems, mappings of both static (DC) and high-frequency electric-field can be obtained. For the static field, the field is chopped to increase the sensitivity performance. For the high-frequency field, an intensity modulation laser, instead of a pulse laser, is used to perform the mapping measurement in frequency domain, instead of in time domain. This approach greatly simplifies the system. An experiment set-up using a vertical cavity surface emitted laser diode (VCSEL) of a wavelength 850 nm and its mapping results for a coplanar waveguide (CPW) with the signal frequency around 1 GHz are reported. 相似文献
153.
154.
Using the notations of convergent series of sets and convergent products of relations, general open mapping theorems are presented which encompass classical results of Banach, Ptak, Khanh, and others. 相似文献
155.
Jiunn‐Hung Pan Yu‐Ma Chou Houn‐Lin Chiu Bo‐Cheng Wang 《Journal of Physical Organic Chemistry》2007,20(10):743-753
Recently, organic diamine compounds have been widely used as hole‐transporting materials. In this work, DFT B3LYP method with the 6‐31G* basis set was performed to investigate the influence of molecular conformation on the reorganization energy of a series of tetra(aryl)benzidine‐based hole‐transport materials. The results indicate that there are two types (i.e., ISB and BD/TPD) of geometric differences of the organic diamines with the relaxation processes. The reorganization energy of the ISB type is lower than that of the BD/TPD type. For the ISB type, the terminal phenyl moiety of the molecular framework plays an important role in determining the Marcus‐type reorganization energy and the central biphenyl moiety does not. A methyl group attached to a terminal phenyl can be used to tune the reorganization energy. According to the statistical analysis, four geometric parameters could affect the reorganization energy of the BD/TPD type. The conformation of either the central biphenyl or the terminal phenyl moiety of the BD/TPD type determines the Marcus‐type reorganization energy associated with the charge transport process at the molecular level. Presumably, this calculation can be employed to predict the electroluminescence (EL) character of the other organic diamines and to improve the design of new hole‐transporting materials in organic light‐emitting devices (OLEDs). Copyright © 2007 John Wiley & Sons, Ltd. 相似文献
156.
M. K. Kabadiyski F. Cristancho C. J. Gross A. Jungclaus K. P. Lieb D. Rudolph H. Grawe J. Heese K. -H. Maier J. Eberth S. Skoda W. -T. Chou E. K. Warburton 《Zeitschrift für Physik A Hadrons and Nuclei》1992,343(2):165-177
The reaction58Ni(36Ar, 4p)90Mo has been studied at a beam energy of 149 MeV. A detector array consisting of the OSIRIS spectrometer (12 Compton-suppressed Ge detectors), four charged-particleδE detectors and seven NE-213 neutron detectors at the VICKSI accelerator in Berlin has been used to measure the gamma radiation inγγ- and particle-γγ-coincidence mode. An additional Ge detector was placed at 162? to the beam direction to provide information on DCO ratios. The level scheme of90Mo has been extended up to an excitation energy of about 12 MeV and probable spin 23?. Some 70 transitions and 40 levels have been newly identified. Spin assignments have been proposed on the basis of measured DCO ratios. Shell model calculations in a model space consisting of the proton 1f 5/2, 2p 3/2, 2p 1/2, and 1g 9/2 orbits and the neutron 2p 1/2, 1g 9/2, 1g 7/2, 2d 5/2, 2d 3/2, and 3s 1/2 orbits with some truncation were made for states above 9? and the predicted structure of these states is discussed. 相似文献
157.
The synthesis of 9- and 10-methylbenz[a]anthracenes by improved methods are described. These new procedures are simple and convenient, and provide the title compounds in good yields and high purity. 相似文献
158.
Fluorescence microscopy has been utilized to investigate the effects of UV irradiation on the organization of keratin intermediate filaments in normal human epidermal keratinocytes. Sun lamp irradiation induced the condensation of keratin intermediate filaments into the perinuclear region and inhibited the reorganization of keratin filaments normally induced by Ca2+. Exposure to UVC appeared to disrupt keratin filaments similarly, whereas UVA had no discernible effect. 相似文献
159.
微分电位溶出分析法应用于金膜电极的研究 总被引:1,自引:0,他引:1
本文介绍将微分电位溶出分析法应用于金膜电极,建立了相应的理论体系和应用条件。可使用的金膜厚度在1.8×10~(-7)~4.3×10~(-7)cm范围。检测限较原法降低近两个数量极。用本法测定花生乳中的铜,回收率在94~102%间。 相似文献
160.
A new analytical method for phenylpropanolamine based on micellar electrokinetic chromatographic separation and laser‐induced fluorescence detection has been developed. Naphthalene‐2,3‐dicarboxaldehyde was used for precolumn derivatization of the nonfluorescent drug. Optimal separation and detection were obtained with an electrophoretic buffer of 50 mM sodium borate (pH 9.5) containing 15 mM sodium dodecyl sulfate and a He‐Cd laser (Δex: 442 nm, Δem: 500 nm). Linearity (r ≥ 0.99) of two orders of magnitude was generally obtained and the concentration limit of detection was in the ng/mL level. Coupled with a simple cleanup procedure, the method can be applied to the analysis of phenylpropanolamine in human plasma, with a limit of detection at 15 ng/mL. Recovery of phenylpropanolamine from plasma samples was about 90%. 相似文献