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121.
122.
The optical constants were measured by elliptical analysis of the reflected light in the visible region. The surface of the bulk specimen were untouched by any physical or chemical treatment. In this way the results seem to give the real optical constants. 相似文献
123.
D. Menzel 《Surface science》1975,47(1):370-383
A survey is given of the basic experimental findings in electron stimulated desorption and of the accepted theoretical model for their explanation. As an example for the test of the theory, the isotope effect in ESD of hydrogen on tungsten surfaces is described, which shows excellent agreement with the predictions of the model. The use of ESD as a surface probe is exemplified with recent work on hydrogen adsorption states on tungsten; the need for generalization of the one-dimensional model to three dimensions becomes clear in this case. Recent developments in theory (a quantum-mechanical treatment of the process) and experiment (promising measurements of the angular distribution of ionic ESD) are shortly discussed. 相似文献
124.
光学特异材料的设计 总被引:2,自引:0,他引:2
Christian Helgert Thomas Pertsch Carsten Rockstuhl Ekaterina PshenaySeverin Christoph Menzel ErnstBernhard Kleyet.al 《中国光学》2010,3(1):1-10
In this contribution we review our latest achievements of combined experimental and theoretical studies to tailor the properties of optical metamaterials(MMs) at will. We give three examples of metamaterial designs that have been realized by means of electron-beam lithography and whose spectroscopic characteristics have been comprehensively investigated. In every case, our experiments are complemented by rigorous numer ical simulations. Particular emphasis is put on the significance of such tailored effective properties of optical MMs 相似文献
125.
An essential property of biological tissues in vivo is the ability to adapt according to respective loading conditions--for example by changing its mass, shape, or internal structure, the latter for instance being associated with fibre reorientation and often denoted as remodelling. In this contribution, a three-dimensional micro-sphere-based constitutive model for anisotropic soft biological tissue is presented, which includes these fibre-reorientation-related remodelling effects. As a key aspect, time-dependent remodelling effects are incorporated by introducing evolution equations for the referential orientations of the integration directions, as present in the computational micro-sphere approach. Based on this, a remodelling formulation for the orthotropic case with two mean fibre orientations will be presented. (© 2010 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
126.
中波红外宽带通滤光膜通常膜系层数多,膜层总厚度非常大(厚度达到10 μm左右),膜层的镀制工艺难度较大。通过分析红外带通滤光片几种设计方法的特点,并结合实际镀制工艺技术,采用了长波通与短波通及非规整薄膜设计技术相结合的方法,设计了以锗材料为基底的中波3 μm~5 μm宽带通滤光膜。该设计大幅度降低了膜层的总厚度(约为8.65 μm),缩短了膜层的镀制周期,提高了膜层的牢固度;在膜层的镀制工艺过程中,通过改变薄膜材料的蒸发速率、修正蒸发硫化锌材料时电子枪的扫描方式、调整蒸发材料在坩埚中的装载方法,使膜层获得了优异的光谱性能,其通带平均透过率大于96%,截止区域的平均透过率小于1%。 相似文献
127.
Menzel D Fastl H Graf R Hellbrück J 《The Journal of the Acoustical Society of America》2008,123(5):2477-2479
This experiment investigates the effect of images of differently colored sports cars on the loudness of a simultaneously perceived car sound. Still images of a sports car, colored in red, light green, blue, and dark green, were displayed to subjects during a magnitude estimation task. The sound of an accelerating sports car was used as a stimulus. Statistical analysis suggests that the color of the visual stimulus may have a small influence on loudness judgments. The observed loudness differences are generally equivalent to a change in sound level of about 1 dB, with maximum individual differences of up to 3 dB. 相似文献
128.
F. Renz V. Martinez M. Klein M. Schott T. Hoffmann M. Blumers I. Fleischer G. Klingelhöfer R. Boča M. Menzel 《Hyperfine Interactions》2008,184(1-3):259-265
The precursors [Fe(III)(N???R???L)Cl] (N???R???LH2=N,N′-bis(2′-hydroxy- 5′-methyl-benzyliden)-1,7-diamino-4-R-4-azaheptane, R ?=? H, methyl(Me)) are high-spin (S?=?5/2) complexes. The Lewis-acidic precursors are combined with Lewis- Base-bridging-units [M(CN) x ] y??? (M = Fe(II), Ru(II), Co(III)) to form heptanuclear star-shaped [M{CN-Fe(III)(N???R???L)} x ]Cl y molecular switches. The star-shaped compounds are high-spin systems at room temperature. On cooling to 20 K some of the compounds exhibit multistability, i.e. several iron(III) centers within a molecule switch to the low-spin state as shown by Mössbauer spectroscopy. 相似文献
129.
F. Löwe Suhrmann Heinrich Menzel G. Schmid R. Brill L. Biermann W. Scheele R. E. Liesegang 《Colloid and polymer science》1942,101(3):329-332
Ohne Zusammenfassung 相似文献
130.
O. Wo R. E. Liesegang H. Menzel Friedrich Müller Haurowitz P. Krais 《Colloid and polymer science》1931,55(3):360-365
Ohne Zusammenfassung 相似文献