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161.
Randomized approximation of Sobolev embeddings, III 总被引:1,自引:1,他引:0
We continue the study of randomized approximation of embeddings between Sobolev spaces on the basis of function values. The source space is a Sobolev space with nonnegative smoothness order; the target space has negative smoothness order. The optimal order of approximation (in some cases only up to logarithmic factors) is determined. Extensions to Besov and Bessel potential spaces are given and a problem recently posed by Novak and Woźniakowski is partially solved. The results are applied to the complexity analysis of weak solution of elliptic PDE. 相似文献
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166.
Joerg Hippler Markus Hollmann Heinrich Juerling Alfred V. Hirner 《Chemical Papers》2009,63(6):742-744
After the synthesis and isolation of methylated bismuth cysteine, its initial identification by IR-spectroscopy was performed,
whereas for definitive identification, high resolution mass spectrometry (ESI-TOF-MS and LTQ Orbitrap) was carried out. 相似文献
167.
The influence of the thickness of a covering liquid layer and its viscosity as well as the impact velocity on energy loss during the normal impact on a flat steel wall of spherical granules with a liquid layer was studied. Free-fall experiments were performed to obtain the restitution coefficient of elastic–plastic Al2O3 granules by impact on the liquid layer, using aqueous solutions of hydroxypropyl methylcellulose with different concentrations for variation of viscosity (1–300 mPa s). In the presence of a... 相似文献
168.
Heinrich Haas und Lucien Lévy 《Fresenius' Journal of Analytical Chemistry》1890,29(1):600-604
Ohne Zusammenfassung 相似文献
169.
Rainer Cremer Mirjam Witthaut Dieter Neuschütz Cyril Trappe Martin Laurenzis Olaf Winkler Heinrich Kurz 《Mikrochimica acta》2000,133(1-4):299-302
Cu3N films for optical data storage were deposited on Si(100) wafers and 0.6 mm thick polycarbonate DVD base material discs at
a temperature of 50 °C by reactive magnetron sputtering. A copper target was sputtered in rf mode in a nitrogen plasma. For
basic investigations concerning the composition and structure of Cu3N, Si wafers were used as substrate material. To study the suitability of Cu3N as an optical data storage medium under technical conditions, Cu3N/Al bilayers were deposited on polycarbonate discs. The composition and structure of the films were investigated by X-ray
photoelectron spectroscopy (XPS) and X-ray diffraction (XRD).
The decomposition of Cu3N into metallic copper and nitrogen was induced and characterized with a dynamic tester consisting of an optical microscope
with an integrated high power laser diode. The change in reflectivity induced by the laser pulses was measured by a high sensitivity
photo detector. Optimized Cu3N films could be decomposed into metallic copper at pulse lengths of 200 ns. The reflectivity change from 3.2% to 33.2% for
completely transformed areas and to 12% for single bits as well as the maximum write data rate of 3.3 Mbit/s demonstrated
the suitability of Cu3N for write once optical data storage. Especially the carrier to noise ratio of 41 dB shows an increase of a factor of 3 for
this novel material as compared to conventional optical data storage media. 相似文献
170.