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61.
Bo Hoffmann Jørgensen Jens Nørkær Sørensen Nadine Aubry 《Theoretical and Computational Fluid Dynamics》2010,24(5):483-496
The flow within a closed cylinder with a rotating lid is considered as a prototype for fundamental studies of vortex breakdown.
Numerical simulations for various parameter values have been carried out to reproduce the known effect of a thin rotating
rod positioned along the center axis as well as analyze the influence of local vorticity sources. As expected, the results
show that the breakdown bubbles in the steady axisymmetric flow can be affected dramatically, i.e., fully suppressed or significantly
enhanced, by rotating the rod. The main contribution of this article is to show that the observed behavior can be explained
by the vorticity generated by the rod locally near the rotating lid and near the fixed lid, as analogous behavior is caused
by the introduction of local vorticity sources in the flow without a rod. Moreover, we describe the influence on the breakdown
bubbles of the vorticity sources by an analytical model. In addition to improving our understanding, this finding should also
open the door to other types of flow control devices capable of generating localized vorticity. 相似文献
62.
Wolfgang J. Philipp Pierre van Iwaarden Heinz Schimmel Nele Meeus Nadine Kollmorgen 《Accreditation and quality assurance》2007,12(3-4):134-138
The reliability of reference materials (RMs) depends on properties such as fitness, robustness, commutability, stability and
homogeneity. The development of RMs for microbiological analysis is especially challenged through questions around the stabilisation
and recovery of viable cells, the dispersion of precise numbers of cells, matrix effects and, when using molecular techniques,
the presence of nucleic acids (e.g. DNA) of dead and live target organisms. However, RMs are indispensable tools for quality
control in microbiological analysis. The Institute for Reference Materials and Measurements (IRMM), as part of the European
Commission, concentrates its efforts on the development of RMs to support the development, implementation and monitoring of
EU legislation. A special focus is given to highly precise RMs for presence/absence and enumeration tests in microbiological
food and water analysis. Another group of new RMs certified by the IRMM comprise DNA-based materials to control the identity
of micro-organisms in qualitative assays. All of these activities serve to improve quality control in microbiological analysis.
Presented at ‘BERM-10’, April 2006, Charleston, SC, USA. 相似文献
63.
64.
Dr. Tiago Rodrigues Nadine Hauser Daniel Reker Dr. Michael Reutlinger Tiffany Wunderlin Dr. Jacques Hamon Dr. Guido Koch Prof. Dr. Gisbert Schneider 《Angewandte Chemie (International ed. in English)》2015,54(5):1551-1555
We report a multi‐objective de novo design study driven by synthetic tractability and aimed at the prioritization of computer‐generated 5‐HT2B receptor ligands with accurately predicted target‐binding affinities. Relying on quantitative bioactivity models we designed and synthesized structurally novel, selective, nanomolar, and ligand‐efficient 5‐HT2B modulators with sustained cell‐based effects. Our results suggest that seamless amalgamation of computational activity prediction and molecular design with microfluidics‐assisted synthesis enables the swift generation of small molecules with the desired polypharmacology. 相似文献
65.
Nadine Große 《Differential Geometry and its Applications》2011,29(6):838-849
We prove the Hijazi inequality, an estimate for Dirac eigenvalues, for complete manifolds of finite volume. Under some additional assumptions on the dimension and the scalar curvature, this inequality is also valid for elements of the essential spectrum. This allows to prove the conformal version of the Hijazi inequality on conformally parabolic manifolds if the spin analog to the Yamabe invariant is positive. 相似文献
66.
??-Amyloid (A??) is a major component of the senile plaques characteristic of Alzheimer disease (AD). Chondroitin sulfate (CS) and glycoaminoglycan (GAG) are also localized throughout the senile plaques in AD. In previous studies, the interaction of the A?? protein with CS immobilized on a chromatographic support and the role of aluminum and copper cations was studied using a molecular chromatographic approach [1, 2]. Here, we demonstrated the direct implication of OH· radical formation on this binding via a novel analytical procedure. The binding of A?? amyloid on CS was accompanied by an OH· radical uptake. The A?¨CCS complex was stabilized by the OH· radical via the creation of about one to two hydrogen bonds. The addition in the medium of a radical scavenger allowed decreasing the A??/CS association and thus confirmed the positive role of these compounds in amyloidosis. 相似文献
67.
68.
Nadine v. Weimara 《Colloid and polymer science》1930,51(1):100-104
Ohne Zusammenfassung
Uebersetzt von Hans Erbring (Leipzig). 相似文献
69.
70.
D. Gotta M. Dörr W. Fetscher G. Schmidt H. Ullrich G. Backenstoss W. Kowald I. Schwanner H.-J. Weyer 《Physics letters. [Part B]》1982,112(2):129-132
The reactions π?3He → nnp and π?3He → nd have been measured in a kinematically complete experiment with stopped pions. The results show strong preference for collinear events. About three quarters of all absorption processes occur as quasi-free absorption on np- or pp-pairs with a ratio of R = 10.1 ± 1.5. The remaining quarter shows energy sharing among all three nucleons and is located in the final-state interaction regions. Branching ratios for all observed final states are given. 相似文献