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31.
32.
Kurt Egger und Manfred Keil 《Fresenius' Journal of Analytical Chemistry》1965,210(3):201-208
Zusammenfassung Durch Anwendung lipophiler Lösungsmittel (z. B. Chloroform— Methanol— Methyl-äthyl-keton = 942) werden Flavonverbindungen auf Polyamid nach vorwiegend verteilungschromatographischen Gesetzmäßigkeiten getrennt. Dadurch kommen gegenüber den bisher verwendeten Fließmitteln neuartige Aufspaltungen zustande. Es erfolgt eine Trennung auch jener Aglykone und Glykoside, die in den bisher beschriebenen Gemischen identische Rf-Werte hatten. Durch Kombination von polarer und lipophiler Entwicklung im zweidimensionalen Chromatogramm sind weitgehende Rückschlüsse auf die Struktur der Verbindungen zu gewinnen. Die Rf-Werte zahlreicher Flavonverbindungen in einer chloroformhaltigen und einer wäßrigen Fließmittelfolge werden vergleichend diskutiert.
Wertvolle Testsubstanzen wurden uns in dankenswerter Weise von Herrn Prof. Dr. Hörhammer, München (K-3-rham. gluc.) und Herrn Prof. Dr. Beckmann, Stuttgart-Hohenheim (K-3-rham. gluo.-7-gluo.) zur Verfügung gestellt. — Die Deutsche Forschungsgemeinschaft hat die Untersuchung durch Sachmittel gefördert. 相似文献
Summary Flavone compounds are separated on polyamide by lipophilic solvent mixtures in a partition-chromatographic way. In contrast to solvent systems used so far, new separations were obtained. Aglycones and glycosides difficultly to resolve hitherto can be easily differentiated now. Combination of polar and lipophilic development in a 2-dimensional chromatogram helps to identify the structure of the compounds. The Rf-values of a number of flavones obtained with solvents containing CHCl3 are compared with those obtained with solvents containing water.
Wertvolle Testsubstanzen wurden uns in dankenswerter Weise von Herrn Prof. Dr. Hörhammer, München (K-3-rham. gluc.) und Herrn Prof. Dr. Beckmann, Stuttgart-Hohenheim (K-3-rham. gluo.-7-gluo.) zur Verfügung gestellt. — Die Deutsche Forschungsgemeinschaft hat die Untersuchung durch Sachmittel gefördert. 相似文献
33.
B. Chabloz R. Corfu J.-P. Egger J.-F. Germond P. Gretillat C. Lunke J. Piffaretti E. Schwarz C. Perrin J.E. Bolger J. Zichy 《Physics letters. [Part B]》1979,81(2):143-146
Pion-carbon 12 elastic and inelastic scattering was measured for both π+ and π? at 162 MeV between 135° and 180°. For this purpose, the angular range of the SIN pion spectrometer was increased to 180° by placing a magnet at the target position. In addition, an amplitude analysis taking Coulomb effects into account was performed. 相似文献
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This paper is based on an Air Force Flight Dynamics Laboratories-sponsored program to evaluate strain gages embedded in boron-epoxy test coupons. The strain gages, embedding techniques and specimen configurations used were relatively uncomplicated. The results of the program showed that the embedded-gage performance was comparable to surface-mounted-gage performance and are intended to provide a basis for more complex applications such as in joints, near holes and in sandwiched metal/fibrous composites. 相似文献
36.
Monteverde M Garbarino G Núñez-Regueiro M Souletie J Acha C Jing X Lu L Pan ZW Xie SS Egger R 《Physical review letters》2006,97(17):176401
We report that the conductance of macroscopic multiwall nanotube (MWNT) bundles under pressure shows power laws in temperature and voltage, as corresponding to a network of bulk-bulk connected Tomonaga-Luttinger liquids (LLs). Contrary to individual MWNTs, where the observed power laws are attributed to Coulomb blockade, the measured ratio for the end and bulk obtained exponents, approximately 2.4, can be accounted for only by LL theory. At temperatures characteristic of interband separation, it increases due to thermal population of the conducting sheets unoccupied bands. 相似文献
37.
S. Bartalucci S. Bertolucci M. Bragadireanu M. Cargnelli C. Curceanu? S. Di Matteo J.-P. Egger C. Guaraldo M. Iliescu T. Ishiwatari M. Laubenstein J. Marton E. Milotti D. Pietreanu T. Ponta A. Romero Vidal D. L. Sirghi F. Sirghi L. Sperandio O. Vazquez?Doce E. Widmann J. Zmeskal 《Foundations of Physics》2010,40(7):765-775
In this paper we describe an experimental test of the validity of the Pauli Exclusion Principle (for electrons) which is based on a straightforward idea put forward a few years ago by Ramberg and Snow (Phys. Lett. B 238:438, 1990). We perform a very accurate search of X-rays from the Pauli-forbidden atomic transitions of electrons in the already filled 1S shells of copper atoms. Although the experiment has a very simple structure, it poses deep conceptual and interpretational problems. Here we describe the experimental method and recent experimental results, which we interpret in the framework of quon theory. We also present future plans to upgrade the experimental apparatus using Silicon Drift Detectors. 相似文献
38.
We derive and analyze the effective low-energy theory for interacting electrons in a cylindrical nanowire made of a strong topological insulator. Three different approaches provide a consistent picture for the band structure, where surface states forming inside the bulk gap correspond to one-dimensional bands indexed by total angular momentum. When a half-integer magnetic flux pierces the nanowire, we find a strongly correlated helical Luttinger liquid topologically protected against weak disorder. We describe how transport experiments can detect this state. 相似文献
39.
Nonlinear transport through interacting single-wall nanotubes containing a few impurities is studied theoretically. Extending the Luttinger liquid theory to incorporate trigonal warping and chirality effects, we derive the current contribution Ie even in the applied voltage V and odd in an orbital magnetic field B, which is nonzero only for chiral tubes and in the presence of interactions. 相似文献
40.