Infrared Photoluminescence
Mostrando 25-31 de 31 artigos, teses e dissertações.
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25. SÃntese e estudo espectroscÃpico de complexos de Ãons lantanÃdeos incorporados em materiais hÃbridos orgÃnicos-inorgÃnicos
In this work two new europium and gadolinium b-diketonate complexes, [Ln(btfa)3(4,4 -bpy)(EtOH)] (Ln = Eu, Gd; 4,4 -bpy = 4,4 -bipyridine; btfa = 4,4,4- trifluoro-l-phenyl- 1,3-butanedione), were prepared and incorporated into a organicinorganic hybrid material. The general formulae of these complexes were confirmed by X-rays single crystal data and elementa
Publicado em: 2007
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26. Silício poroso obtido por ataque químico / Porous silicon obtained by chemical etching
This work reports on a detailed study of porous Si layers produced by chemical etch in p+-type (001) Si wafers with solutions of HF:HNO3 at concentrations of 50:1 and 500:1 added with NaNO2 diluted at 0.1 g/L. Sets of samples with etching times from 1 to 30 min were fabricated. Porous layers etched with the 500:1 solution during 1 to 10 min were found to be
Publicado em: 2006
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27. Optical properties of K2LiAlF6:Cr3+ / Propriedades ópticas do K2LiAlF6:Cr3+
The interest in the study of insulating materials doped with transition metals arises from the fact that these systems present wide emission bands in the visible and near infrared regions, which turns them especially attractive as active media for tunable radiation. In this work we will present photoluminescence, absorption and excitation measurements at roo
Publicado em: 2006
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28. CaracterizaÃÃo de filmes de CdS preparados pela tÃcnica de deposiÃÃo por laser pulsado (PLD)
In this work, we have designed and installed a system for thin films deposition using a Nd:YAG laser as the source of energy for evaporation. The technique is known as: Pulsed Laser Deposition, PLD. The excitation wavelengths used were 1064 nm and 532 nm. The target was a pressed powder tablet of CdS. Characterization of the films was performed using X-rays
Publicado em: 2002
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29. Propriedades Ópticas de Semicondutores Orgânicos à Base de Polímeros Emissores de Luz / Optical proprieties of organic semiconductors based on light emitting polymers.
In this work, we studied the optical proprieties of absorption and emission of luminescent conjugated polymers based on poly(p-phenylene vinylene) (PPV). This material was processed in thin films by casting, spin-coating, self-assembled (SA) e Langmuir-Blodgett (LB) techniques, available in the Grupo de Polímeros Bernhard Gross, where the samples were chara
Publicado em: 2001
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30. Propriedades opticas de carvões minerais e grafites
Coals from southern Brazil with high mineral matter content were studied with infrared absorption spectroscopy and reflectivity measurements. The results of Raman and photoluminescence experiments are also reported. Reference measurements were performed on coals with low mineral content and graphite?s (which are structurally similar to the coals with the hig
Publicado em: 1981
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31. Solid-state fluorescence of the trihydrate phases of ampicillin and amoxicillin
The purpose of this work was to study the effects of crystal structure on the solid-state photoluminescence of the trihydrate phases of ampicillin and amoxicillin, and to contrast these spectra with analogous spectra obtained on the molecules dissolved in a solution phase. The polymorphic identity of the analytes was established using x-ray powder diffractio
Springer-Verlag.