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21.
A. Korn 《Acta Mathematica》1909,32(1):81-96
Ohne Zusammenfassung 相似文献
22.
Cristina M. Quintella Yuji N. Watanabe Mauro Korn Marcelo Embiruçu 《Analytica chimica acta》2004,523(2):293-300
A fully mechanized set-up was built for the experimental determination of bi-dimensional dispersion with high spatial resolution (2400 μm2). Gravitational and wall effects in a single stream were evaluated by using time-based sampling and a micro-flow cell. Vertical upward and downward flows as well as horizontal flows were investigated. Ethylene glycol (MEG) and Rhodamine B in MEG were used as carrier and sample solutions, respectively. Longitudinal profiles were obtained by laser induced total fluorescence (LIF) at up to 19 transversal sites and combined to generate high-resolution bi-dimensional profiles. A two frontal maxima pattern was observed for all flows. The volumetric fraction of RB shape was highly stretched for downward flow and there was high asymmetry for horizontal flow. The sensitivity of three dispersion parameters was evaluated: maximum peak value, peak half-width at half-height, and peak area.Data modeling showed that the tanks-in-series was more sensitive to wall effects, had good adjustment with only one tank for upward and horizontal flow and needed two tanks for downward flow which was attributed to the latter having higher dispersion. A black box empirical modeling described better the gravitational effect and allowed to identify a parameter sensitive to upward and downward flow as well as hinting to two inner streams within the horizontal flow. It also pointed to a wall dispersion contribution of twice that of the liquid-liquid dispersion. 相似文献
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Nagy K Redeuil K Williamson G Rezzi S Dionisi F Longet K Destaillats F Renouf M 《Journal of chromatography. A》2011,1218(3):491-497
There is a substantial amount of published literature on the bioavailability of various coffee components including the most abundant metabolites, caffeic and ferulic acids. Surprisingly, to date, the appearance of dimethoxycinnamic acid derivatives in humans has not been reported despite the fact that methylated form of catechol-type polyphenols could help maintain, modify or even improve their biological activities. This study reports an LC-MS method for the detection of dimethoxycinnamic acid in human plasma after treatment with an esterase. Liquid chromatography, including the combination of methanol and acetonitrile as organic eluent, was optimized to resolve all interferences and enable reliable detection and identification of 3,4-dimethoxycinnamic and 3,4-dimethoxy-dihydrocinnamic acids. In addition to the good mass accuracy achieved (better than 5 ppm), tandem mass spectrometric and co-chromatography experiments further confirmed the identity of the compounds. The optimized method was applied to analyze samples obtained immediately, 1 and 10 h after coffee ingestion. The results show that in particular 3,4-dimethoxycinnamic acid appears in high abundance (~380 nM at 60 min) in plasma upon coffee intake, indicating that it is important to consider these derivatives in future bioavailability and bioefficacy studies. 相似文献
26.
Balázsik K Szori K Szollosi G Bartók M 《Chemical communications (Cambridge, England)》2011,47(5):1551-1552
In competitive racemic hydrogenation of methyl benzoylformate (MBF) + ethyl pyruvate (EP) binary mixture over Pt/Al(2)O(3): k(MBF) > k(EP), but in competitive enantioselective hydrogenation k(MBF) < k(EP); the phenomenon verified for the first time is dependent on the adsorption strength of the surface complexes of various compositions (MBF-Pt, EP-Pt, MBF-CD-Pt, EP-CD-Pt, CD = cinchonidine). 相似文献
27.
By weakening the counit and antipode axioms of aC
*-Hopf algebra and allowing for the coassociative coproduct to be nonunital, we obtain a quantum group, that we call aweak C
*-Hopf algebra, which is sufficiently general to describe the symmetries of essentially arbitrary fusion rules. This amounts to generalizing the Baaj-Skandalis multiplicative unitaries to multipicative partial isometries. Every finite-dimensional weakC
*-Hopf algebra has a dual which is again a weakC
*-Hopf algebra. An explicit example is presented with Lee-Yang fusion rules. We briefly discuss applications to amalgamated crossed products, doubles, and quantum chains.Supported by the Hungarian Scientific Research Fund, OTKA T 016 233.Supported by the Hungarian Scientific Research Fund, OTKA-1815. 相似文献
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29.
Ralf Korn 《Mathematische Semesterberichte》2008,55(1):19-42
Zusammenfassung Es wird ein überblick über die Arbeitsgebiete und die wichtigsten Resultate der modernen
Finanzmathematik gegeben. Hierbei soll durch ein klares Herausstellen der wichtigsten Prinzipien und eine
Trennung zwischen ihrer Demonstration und der in der Praxis ben?tigten, theoretisch anspruchsvollen
stochastischen Analysis einem gro?en Leserkreis ein verst?ndlicher Zugang zur Finanzmathematik
erm?glicht werden. 相似文献
30.
C. Bar-Isaac U. Korn S. Shtrikman D. Treves 《Applied Physics A: Materials Science & Processing》1974,5(2):121-125
Dynamic measurements of velocity and temperature yield information on the temperature distribution and the thermal thickness of the evaporation front caused by focused laser irradiation on metals. The thermal thickness of the evaporation front is inversly proportional to the steady-state velocity of the front. Direct temperature values are obtained by measuring the thermoelectric signals from thermocouple junctions of 10 μm average dimensions, located at the back side of the drilled sample. Experimental results are compared to thermal models theory and the implications concerning the drilled efficiency are considered. 相似文献