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101.
As existing facilities / structures are modi.ed, as engineering knowledge advances and as the requirements to extend life increase, industries must demonstrate that operations can continue safely and economically. This is one objective of the Thematic Network SAFERELNET [1], where reassessment strategies are covered. One possibility to enhance the knowledge is an experimental assessment. This study aims to identify system parameters like mass, damping and stiffness of a dynamical system using wavelet packets. (© 2005 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
102.
Lorenz Beckmann Uta Sandy Tretbar Reni Kitte Maik Tretbar 《Molecules (Basel, Switzerland)》2022,27(8)
Drimane and coloratane sesquiterpenoids are present in several plants, microorganisms, and marine life. Because of their cytotoxic activity, these sesquiterpenoids have received increasing attention as a source for new anticancer drugs and pharmacophores. Natural drimanes and coloratanes, as well as their semi-synthetic derivatives, showed promising results against cancer cell lines with in vitro activities in the low micro- and nanomolar range. Despite their high potential as novel anticancer agents, the mode of action and structure–activity relationships of drimanes and coloratanes have not been completely enlightened nor systematically reviewed. Our review aims to give an overview of known structures and derivatizations of this class of sesquiterpenoids, as well as their activity against cancer cells and potential modes-of-action. The cytotoxic activities of about 40 natural and 25 semi-synthetic drimanes and coloratanes are discussed. In addition to that, we give a summary about the clinical significance of drimane and coloratane sesquiterpenoids. 相似文献
103.
G. Lehmann B. Binkle und A. Scheller 《Fresenius' Journal of Analytical Chemistry》1986,323(4):355-358
Zusammenfassung Lebensmittel sind Vielkomponentengemische unterschiedlicher Substanzen, wobei die zum Färben verwendeten Farbstoffe durch die Matrix der Lebensmittel unterschiedlich fest adsorbiert werden können. In der vorliegenden Arbeit wird erstmals ein umfassender Analysengang zur Isolierung und Identifizierung von Lebensmittelfarbstoffen in Lebensmitteln unterschiedlicher Zusammensetzung durch Ionenpaar-Extraktion und Chromatographie beschrieben. Als Ionenpaarbildner hat sich besonders Cetylpyridiniumchlorid für Anionfarbstoffe bewährt.
Dem Vorsitzenden der Farbstoffkommission der DFG, Herrn Prof. Dr. D. Schmähl, Heidelberg, zum 60. Geburtstag gewidmet
Dem Verband der Chemischen Industrie, Fonds der Chemischen Industrie, danken wir für die gewährte Unterstützung, der Deutschen Forschungsgemeinschaft für die Gewährung einer Sachbeihilfe. 相似文献
Identification of dyes in foodstuffs by ion-pair extraction
Summary Foodstuffs are multi-component mixtures of different inorganic and organic compounds. Therefore, the identification of dyes in foodstuffs is a most difficult task. A scheme of analysis is given for dyes in different foodstuffs by use of ion-pair extraction and ion-pair chromatography. Cetylpyridinium chloride has proved to be particularly advantageous for forming ion-pairs with anionic dyes.
Dem Vorsitzenden der Farbstoffkommission der DFG, Herrn Prof. Dr. D. Schmähl, Heidelberg, zum 60. Geburtstag gewidmet
Dem Verband der Chemischen Industrie, Fonds der Chemischen Industrie, danken wir für die gewährte Unterstützung, der Deutschen Forschungsgemeinschaft für die Gewährung einer Sachbeihilfe. 相似文献
104.
U. Wollenberger F. Scheller D. Pfeiffer V.A. Bogdanovskaya M.R. Tarasevich G. Hanke 《Analytica chimica acta》1986
The electrode involves a layer of co-immobilized glucose oxidase and laccase in a gelatin membrane placed over a modified oxygen electrode. Hexacyanoferrate(III) is added to the samples to oxidize reductive interferents such as ascorbic acid, and the hexacyanoferrate(II) formed is re-oxidized by a laccase-catalyzed reaction. Ascorbic acid is completely eliminated up to a concentration of 20 mM in the sample. 相似文献
105.
106.
107.
NMR-spectroscopic Investigations on Solvation of Lanthanoide Complexes of Tetraphenylimidodiphosphate The additional coordination of solvent molecules to chelate complexes LnA3 of rare earth ions (Ln3+) and tetraphenylimidodiphosphate ions (A?) has been studied by 1H-NMR spectroscopy. The nature of the solvent has a great influence on the spectra observed especially in the case of paramagnetic Ln3+ ions. In acetone as solvent TmA3 forms a disolvate preferably. The brutto stability constants for the additional coordination of acetone as ligands by TmA3 are β1 = (0.013 ± 0.003) mol?1 · l and β2 = (0.016 ± 0.001) mol?1 · l2. 相似文献
108.
109.
Maik Nowak 《Rheologica Acta》2001,40(4):366-372
The first normal stress differences N
1 of a highly dilute cationic surfactant solution are investigated in a cone-and-plate rheometer. In continuation of a previous
paper (Nowak 1998), where the buildup of a shear induced structure in such a solution was attained after a reduced deformation,
the N
1 turned out to be in proportion to the square of the shear rate γ˙ reduced by a critical value γ˙
c
in a first range above γ˙
c
. At higher shear rates the N
1 tend to lower values than predicted by this relation.
Relaxation experiments were performed in the same geometry to determine the characteristic time scales of the shear induced
state's decay. In the lower range above &γdot;
c
the stress decay is a monoexponential process, while a second time constant has to be introduced to describe the relaxation
in that range, where the N
1 deviate from the parabolic dependence of the reduced shear rate.
Received: 10 May 1999 Accepted: 15 November 2000 相似文献
110.