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61.
Alban A. Letailleur Sergey Yu Grachev Elin Søndergård Christophe Couteau Gilles Lérondel Emmanuelle Peter 《Journal of luminescence》2011,131(12):2646-2651
The application of alumina-doped ZnO (AZO) films as luminescent material for large area lighting sources has been evaluated. Thin films were grown on quartz using magnetron sputtering and subsequently annealed under argon atmosphere in a rapid thermal annealing experiment. Below 550 °C, red-shift of the optical band gap and increase of the visible emission are observed in agreement with Al diffusion and formation of interstitial oxygen atoms. At temperatures higher than 800 °C, diffusion is activated and Ostwald ripening leads to the formation of larger grains and an increase of the crystalline phase. The photoluminescence (PL) intensity is enhanced, specifically in the UV range. As a result the emission spectrum of AZO thin films can be adjusted by the annealing conditions, with equal contributions from the UV and orange parts of the PL spectrum resulting in an efficient white emission as quantified using the color space map of the Commission Internationale de l'Éclairage. 相似文献
62.
Batalioto F Martins OG Duarte AR Figueiredo Neto AM 《The European physical journal. E, Soft matter》2011,34(1):10
In this work we investigate the influence of the adsorption of ions on the impedance spectroscopy of an electrolytic cell.
We consider that the positive and negative ions present in a dielectric liquid are adsorbed in the electrode surfaces with
different adsorption energies. This difference in adsorption energies causes an additional plateaux in the limit of the low-frequency
range of the real part of the impedance Z . In the same frequency range, a second minimum in the imaginary part of Z is predicted. The theory is illustrated with measurements of the impedance of an electrolytic solution in the frequency range
from 10-2Hz to 1KHz. A comparison between the present model and others from the literature to describe the experimental results is
also made. 相似文献
63.
Sena C Godinho MH Sebastião PJ Sousa D Neto FA 《The European physical journal. E, Soft matter》2011,34(1):8-11
We report on an experimental study of the structures presented by urethane/urea elastomeric films without and with ferromagnetic
nanoparticles incorporated. The study is made by using the X-ray diffraction, nuclear magnetic resonance (NMR), optical, atomic
and magnetic force (MFM) microscopy techniques, and mechanical assays. The structure of the elastomeric matrix is characterized
by a distance of 0.46nm between neighboring molecular segments, almost independent on the stretching applied. The shear casting
performed in order to obtain the elastomeric films tends to orient the molecules parallel to the flow direction thus introducing
anisotropy in the molecular network which is reflected on the values obtained for the orientational order parameter and its
increase for the stretched films. In the case of nanoparticles-doped samples, the structure remains nearly unchanged although
the local order parameter is clearly larger for the undoped films. NMR experiments evidence modifications in the molecular
network local ordering. Micrometer size clusters were observed by MFM for even small concentration of magnetic particles. 相似文献
64.
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67.
Lange Camila Neves Figueiredo Ana Maria Graciano Enzweiler Jacinta Castro Liliana 《Journal of Radioanalytical and Nuclear Chemistry》2017,311(2):1323-1332
Journal of Radioanalytical and Nuclear Chemistry - The impact of a scrapyard of impounded vehicles in São Paulo state on topsoil was evaluated for As, Ba, Co, Cr, Cu, Mo, Ni, Pb, V, Zn and... 相似文献
68.
The basic relationships required to analyse permeability data of fluorite-based solid electrolytes are rewritten in order
to account for an overpotential term related to slow surface exchange. Results of a gadolinia doped ceria solid electrolyte
suggest that surface exchange might limit the permeability especially at low Po2 and temperature. However, the analysis of the data with different relationships leads to somewhat different estimates of
the electron and hole conductivity and overpotential values.
Paper presented at the 5th Euroconference on Solid State Ionics, Benalmádena, Spain, Sept. 13–20, 1998 相似文献
69.
M. M. Elin 《Siberian Mathematical Journal》1994,35(5):936-940
Translated fromSibirskiî Matematicheskiî Zhurnal, Vol. 35, No. 5, pp. 100–1005, September–October, 1994. 相似文献
70.
It has been shown by Trudinger and Moser that for normalized functions u of the Sobolev space ??1, N (Ω), where Ω is a bounded domain in ?N, one has ∫Ω exp(αN|u|N/(N ? 1))dx ≤ CN, where αN is an explicit constant depending only on N, and CN is a constant depending only on N and Ω. Carleson and Chang proved that there exists a corresponding extremal function in the case that Ω is the unit ball in ?N. In this paper we give a new proof, a generalization, and a new interpretation of this result. In particular, we give an explicit sequence that is maximizing for the above integral among all normalized “concentrating sequences.” As an application, the existence of a nontrivial solution for a related elliptic equation with “Trudinger‐Moser” growth is proved. © 2002 John Wiley & Sons, Inc. 相似文献