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排序方式: 共有598条查询结果,搜索用时 187 毫秒
591.
Agáta Dujavová Michaela Valeriánová Vladimír Štrbík Zuzana Matkovičová Gustav Plesch Ivan Kostič 《Central European Journal of Physics》2007,5(2):229-235
Rhenium avoids air degradation of the target as well as of precursor thin films during the preparation of high temperature
Tl-based superconductors. Addition of Re has been used during synthesis of oriented Tl(Re)-Ba-Ca-Cu-O films. High temperature
superconducting Tl-based thin films were prepared by a two step method combining RF magnetron sputtering and ex-situ thallination. Precursors with a composition of Re0.1Ba2Ca2Cu3Ox were deposited on a CeO2 buffered R-plane sapphire substrate. The sputtered films were prepared at room temperature in an Ar atmosphere. The thallination
of the precursor films was performed in a one zone configuration, where both the pellet and precursor film were kept at the
same temperature. The thallination temperature varied in the range of 850–880°C and samples were held for 30, 45 and 60 min
at this temperature in a flowing oxygen atmosphere. Besides Tl-2212, X-ray diffraction reveals the possibility of also preparing
the Tl-2223 phase, which was until now not reported in a Re doped form.
Presented at 5-th International Conference Solid State Surfaces and Interfaces, November 19–24, 2006, Smolenice Castle, Slovakia 相似文献
592.
Aggregates of misfolded proteins play an important role in diseases such as Alzheimer's. Here it is demonstrated how the anionic oligothiophene p-FTAA interacts with and influences pre-fibrillar protein assemblies during the earlier stages of in vitro fibrillation. Conjugated polythiophenes have previously been demonstrated to detect and discriminate between different types of protein aggregates and also introduce luminescent or conductive properties to these nanoscale fiber structures. Fluorescence spectroscopy, DLS, TEM and FCS are employed to follow the interplay between p-FTAA and insulin during in vitro fibrillation. 相似文献
593.
Tobias Str?mgren Geert Brethouwer Gustav Amberg Arne V. Johansson 《Flow, Turbulence and Combustion》2011,86(3-4):477-495
An Eulerian turbulent two phase flow model using kinetic theory of granular flows for the particle phase was developed in order to study evolving upward turbulent gas particle flows in a pipe. The model takes the feedback of the particles into account and its results agree well with experiments. Simulations show that the pipe length required for particle laden turbulent flow to become fully developed is up to five times longer than an unladen flow. To increase the understanding of the dependence of the development length on particle diameter a simple model for the expected development length was derived. It shows that the development length becomes shorter for increasing particle diameters, which agrees with simulations up to a particle diameter of 100 ??m. Thereafter the development length becomes longer again for increasing particle diameters because larger particles need a longer time to adjust to the velocity of the carrier phase. 相似文献
594.
Sanders HM Iafisco M Pouget EM Bomans PH Nudelman F Falini G de With G Merkx M Strijkers GJ Nicolay K Sommerdijk NA 《Chemical communications (Cambridge, England)》2011,47(5):1503-1505
CryoTEM demonstrates that a CNA35-bearing liposomal MRI contrast agent selectively binds to poorly assembled collagen type I as opposed to well-assembled collagen fibrils, whereas monomeric CNA35 binds to all forms of collagen. It is shown that upon conjugation to liposomes and micelles CNA35 loses its ability to dissociate ordered collagen fibrils and thereby to create its own binding sites. 相似文献
595.
In situ photoexcitation of silver-doped titania nanopowders for activity against bacteria and yeasts
Kowal K Wysocka-Król K Kopaczyńska M Dworniczek E Franiczek R Wawrzyńska M Vargová M Zahoran M Rakovský E Kuš P Plesch G Plecenik A Laffir F Tofail SA Podbielska H 《Journal of colloid and interface science》2011,362(1):50-57
Photocatalytic and in situ microbial activity of the amorphous and annealed states of Ag-doped and un-doped titania were examined. Studies on their structure, morphology, composition, and the photo-absorption characteristics of these materials were performed. These results were correlated with the photocatalytic and microbial activity against methicillin resistant Staphylococcus aureus K324 (MRSA), methicillin susceptible S. aureus ATCC 25923 (MSSA), Escherichia coli PA 170, and yeasts Candida albicans ATCC 90028. The annealed powders containing anatase form of titania exhibited relatively higher photocatalytic activity,corresponding to activity against MRSA,when exposed to UV-A radiation. In comparison, amorphous powders exhibited low photoactivity and showed poor antibacterial performance against MRSA under UV-A exposure. Doping of amorphous titania with Ag resulted in an anti-MRSA effect without exposure to UV radiation. In the Ag-doped crystalline anatase samples, the size of Ag primary nanocrystallites increased, which led to the decrease in the surface concentration of Ag and detriment anti-MRSA activity. 相似文献
596.
597.
Gustav Grether 《PAMM》2017,17(1):797-798
As a major task of the DLR-internal project “Next Generation Train”, robust state feedback control with gain scheduling was sucessfully applied to guide the experimental running gear with independently rotating wheels (IRWs) at a 1:5 scaled roller rig, see [1]. However, the adaptation of the control structure to the 1:1 multibody model requires to additionally consider the properties of curved tracks. For that reason, an analytical model of a running gear with IRWs is deduced using Euler-Lagrange-equations and taking superelevation and track curvature into account. Furthermore, the complexity of the system is reduced to allow for a robust feedback control synthesis and feed-forward control including model inversion. Finally, the model is discussed and a first approach for a feed-forward control in transition curves is shown. (© 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
598.