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We present the fabrication and optical investigation of highly random self-assembled, nano-scale films, probing their influence
on the luminescence properties of near surface CdSe/ZnS colloidal quantum dots. When compared to quantum dots distributed
on unstructured quartz substrates, the average luminescence intensity is found to be enhanced by a factor of 160×. The silver
nanoparticles are prepared using slow thermal evaporation on quartz substrates and post-deposition annealing to produce a
randomly-arranged layer of smooth nano-islands. Clear polarization dependent hot spots are observed. Such hot spots deliver
a maximal enhancement of the emission intensity of 240× and have a spatial density of (0.050±0.002) μm − 2. The results show that silver nano-island films strongly enhance the optical efficiency of near quantum dots emitters. 相似文献
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Scott C. Hagen D. Michael Parrish ? 《International Journal of Computational Fluid Dynamics》2013,27(7):585-595
This paper presents an a posteriori approach to unstructured mesh generation via a localized truncation error analysis and applies it to the Western North Atlantic Tidal (WNAT) model domain. The WNAT model domain encompasses the Gulf of Mexico, the Caribbean Sea, and the North Atlantic Ocean east to the 60°W Meridian. Herein, we pay particular attention to the area surrounding the Bahamas. A bathymetric data set with fine resolution is employed in seven separate linear, harmonic simulations of shallow water tidal flow for seven different tidal-forcing constituents. Each set of simulation results is used to perform a truncation error analysis of a linear, harmonic form of the depth-averaged momentum equations for each of the seven different tidal-forcing frequencies. Truncation error is then driven to a more uniform, domain-wide value by solving for local node spacing requirements. The process is built upon successful research aiming to produce unstructured grids for large-scale domains that can be used in the accurate and efficient modeling of shallow water flow. The methodology described herein can also be transferred to other modeling applications. 相似文献
76.
Alfin D. N. Vaz Wei Wei Wang Andrew J. Bessire Raman Sharma Anne E. Hagen 《Rapid communications in mass spectrometry : RCM》2010,24(14):2109-2121
A simple procedure is described to identify acyl‐glucuronides by coupled liquid chromatography/mass spectrometry after derivatization to a hydroxamic acid with hydroxylamine. The reaction specificity obviates the need for isolation of the acyl‐glucuronide from an extract. Glucuronides derived from carbamic acids, and alkyl‐ and aromatic amines, are inert to the derivatization reaction conditions, making the hydroxamic acid derivative a fingerprint for acyl‐glucuronides. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
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Pavel Exner Takashi Ichinose Hagen Neidhardt Valentin A. Zagrebnov 《Integral Equations and Operator Theory》2007,57(1):67-81
We introduce a new product formula which combines an orthogonal projection with a complex function of a non-negative operator.
Under certain assumptions on the complex function the strong convergence of the product formula is shown. Under more restrictive
assumptions even operator-norm convergence is verified. The mentioned formula can be used to describe Zeno dynamics in the
situation when the usual non-decay measurement is replaced by a particular generalized observables in the sense of Davies. 相似文献
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Ohne Zusammenfassung
The online version of the original article can be found at http://dx.doi.org/10.1007/s00591-005-0103-z 相似文献
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