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191.
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
192.
To study the ion‐conductive and dielectric properties of polymer electrolytes based on poly(ethylene carbonate) (PEC) with lithium bis(trifluoromethanesulfonyl)imide (LiTFSI), the complex permittivity and conductivity were measured using broadband dielectric spectroscopy. The temperature dependence of the relaxation frequency and ionic conductivity for PEC‐LiTFSI electrolytes (1 – 200 mol%) indicates that the segmental motion of PEC chains decreases with the addition of just 1 mol% of Li salt and increases with increasing concentration above 10 mol%. According to the Walden rule for PEC‐based electrolytes, the value of deviation from the reference line increased, and the fragility and decoupling exponents decreased with increasing salt concentration. These results indicate that there are large numbers of ion pairs and aggregated ions, which imply low ionicity and reduced fragility in highly concentrated PEC‐based electrolytes. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
193.
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