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Tortora P Abashin M Märki I Nakagawa W Vaccaro L Salt M Herzig HP Levy U Fainman Y 《Optics letters》2005,30(21):2885-2887
We apply heterodyne scanning near-field optical microscopy (SNOM) to observe with subwavelength resolution the amplitude and phase of optical fields propagating in several microfabricated waveguide devices operating around the 1.55 microm wavelength. Good agreement between the SNOM measurements and predicted optical mode propagation characteristics in standard ridge waveguides demonstrates the validity of the method. In situ observation of the subwavelength-scale distribution and propagation of optical fields in straight and 90 degrees bend photonic crystal waveguides facilitates a more detailed understanding of the optical performance characteristics of these devices and illustrates the usefulness of the technique for investigating nanostructured photonic devices. 相似文献
184.
TRACE METALS IN VANDA LAKE IN ANTARCTICA——A VERTICAL MIGRATION MODEL OF TRACE METALS IN CLOSED BASIN
Vanda Lake, a typical dimictic CaCl_2 type salt lake, is located in the Wright Valley inAntarctica. Based on the chemical and physical features of the salt lake water, the authorsdiscussed the vertical geochemical distribution of Fe, Mn, Pb, Cr, Cu, Co, Ni, Cd in the lake,and their vertical migration in lake waters, and have tried to set up a model of vertical mi-gration of these trace elements in the water of a closed chloride type salt lake. 相似文献
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John Lake 《Journal of Combinatorial Theory, Series B》1975,18(2):170-174
The de Bruijn-Erdös theorem states that the chromatic number of a graph is n (a finite number) if and only if the chromatic numbers of all its finite subgraphs are ≤n. We prove a generalization of this result. 相似文献
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A system has been developed and tested for the balancing of rotating systems without interrupting operation. Several procedures are proposed for balancing, in which only measurements of the bearing vibrations are used. Large generators, turbines, fans, pumps and compressors are potential applications. 相似文献
189.
Nurettin Pirinççioglu İrfan Açıkgöz Mustafa Saltı 《International Journal of Theoretical Physics》2007,46(5):1318-1333
In this work, in order to compute energy and momentum distributions (due to matter plus fields including gravitation) associated with the Brans–Dicke wormhole solutions we consider Møller’s energy-momentum complexes both in general relativity and the teleparallel gravity, and the Einstein energy-momentum formulation in general relativity. We find exactly the same energy and momentum in three of the formulations. The results obtained in teleparallel gravity is also independent of the teleparallel dimensionless coupling parameter, which means that it is valid not only in the teleparallel equivalent of general relativity, but also in any teleparallel model. Furthermore, our results also sustains (a) the importance of the energy-momentum definitions in the evaluation of the energy distribution of a given spacetime and (b) the viewpoint of Lessner that the Møller energy-momentum complex is a powerful concept of energy and momentum. (c) The results calculated supports the hypothesis by Cooperstock that the energy is confined to the region of non-vanishing energy-momentum tensor of matter and all non-gravitational fields. 相似文献
190.
H测定过MgSO_4-C_2H_5OH-H_2三元系在25℃、50℃、75℃的液固平衡和部分不饱和溶液汽液平衡的总压和分压。本文补充了30℃、0℃和-5℃时的溶解度数据,得到分层温度和浓度范围,绘出了溶解度图。测定了25℃和30℃饱和溶液的密度,粘度和平衡总压力。根据Jaques“假二元系”理论用Wilson、Uniquac和NRTL活度方程计算了溶 相似文献