Modulation Spectroscopy
Mostrando 1-12 de 37 artigos, teses e dissertações.
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1. Inhibición de la corrosión del acero ASTM A192 en solución de ácido clorhídrico por el mucilago de Linum usitatissimum
ABSTRACT In this study, the inhibition of the corrosion of ASTM A192 steel in HCl 0,5 M at temperature different, by the Linum usitatissimum mucilage, was investigated using techniques: Tafel extrapolation, linear polarization resistance, electrochemical impedance spectroscopy and electrochemical frequency modulation. The Linum mucilage acts as an optimum co
Matéria (Rio J.). Publicado em: 19/07/2018
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2. Sistemas CDMA ópticos coerentes baseados em codificação de fase espectral / Coherent optical CDMA systems based on spectral phase coding
In this work we perform a comprehensive analysis of a spectral phase-encoded time spreading optical code division multiple access (SPECTS-OCDMA) system. Despite being a numerical study, efforts were concentrated on the investigation of more realistic scenarios using as much information as possible from implemented test-beds in laboratories. In this context,
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 11/12/2012
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3. Espectroscopia de modulação de poços quânticos simples e duplos de GaAs/AlGaAs
Este trabalho tem como objetivo principal estudar os estados fundamental e excitado de poços quânticos duplos acoplados (PQDAs) de GaAs/AlxGa1-xAs com diferentes espessuras de "spikes", em função da temperatura.Poços quânticos duplos acoplados simétricos correspondem a dois poços quânticos simples idênticos separados por uma barreira estreita, de t
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 22/03/2010
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4. Modulation of ROS production in human leukocytes by ganglioside micelles
Recent studies have reported that exogenous gangliosides, the sialic acid-containing glycosphingolipids, are able to modulate many cellular functions. We examined the effect of micelles of mono- and trisialoganglioside GM1 and GT1b on the production of reactive oxygen species by stimulated human polymorphonuclear neutrophils using different spectroscopic met
Brazilian Journal of Medical and Biological Research. Publicado em: 2010-10
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5. Estudo da interação da peroxidase de raiz forte em interfaces nanoestruturadas / Study of horseradish peroxidase interaction in nanostructured interfaces
A study has been performed on the interaction of the enzyme horseradish peroxidase (HRP) in nanostructured interfaces and their possible application in biosensors for hydrogen peroxide. The nanostructured films were obtained with the Langmuir, Langmuir-Blodgett (LB) and layer-by-layer (LbL) methods. The interaction between HRP and species at interfaces was i
Publicado em: 2008
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6. Caracterização térmica e óptica por espectroscopia fotoacústica: um método inverso / Thermal and optical characterization by photoacoustic spectroscopy: a inverse approach
Photoacoustic spectroscopy is a very effective technique for optical and thermal characterization of materials. This technique is based on photoacoustic effect. It occurs when a material sample placed inside a closed cell filled with any gas is illuminated with periodically interrupted light. This effect depends on many parameters as modulation frequency of
Publicado em: 2007
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7. Acoplamento spin-fonon em sistemas magneticamente frustrados / Spin-phonon coupling in magnetically frustrated systems
In this thesis we present an investigation of two magnetically frustrated systems, namely the RMn2O5 series (R = Eu, Bi, Dy) and the intermetallic compound GdAl3, in addition to the double perovskite compound Sr2CoUO 6. These systems were studied mainly using the Raman spectroscopy technique and complemented with magnetic susceptibility measurements. For the
Publicado em: 2007
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8. Modulation of the lignification process for application of jasmonic acid and 2,4-dichlorophenoxyacetic acid in Eucalyptus urophylla S. T. Blake. / Modulação do processo de lignificação por aplicação de ácido jasmônico e ácido 2,4-diclorofenoxiacético em Eucalyptus urophylla S. T. Blake
Lignin is a important a biomacromolecule for several biologic process in plants, the most important process is to give necessary rigidity to keep the stem verticality, and water and minerals circulation. This research was carried out with Eucalyptus urophylla seedling and the result can help other biothecnological studies. In this research were applied diffe
Publicado em: 2005
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9. Espectroscopia de alta resolução num feixe supersônico de sódio / Ultra-high resolution spectroscopy in a supersonic sodium beam
This work reports measurements in the vibrational bands of the A1∑+u→X1∑+g transition for Sodium dimer, produced in a supersonic expansion of the metal vapor into the vacuum. For the determination of the molecular constants we used righ-resolution laser spectroscopy techniques: Resonance Fluorescence, Stimulated Raman and Optical Depletion.
Publicado em: 1993
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10. Mistura de ondas ressonante em absorvedores saturaveis
A study of resonant interactions of two or more waves coupled through population modulation in a saturable absorber (SA) is presented. In the case ot two strong, non collinear waves at equal frequencies, the population in the SA is spatially-modulated and the incident waves are scattered into the various orders of the population grating. A non perturbative r
Publicado em: 1984
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11. Electron-nuclear double resonance spectroscopy (and electron spin-echo envelope modulation spectroscopy) in bioinorganic chemistry
This perspective discusses the ways that advanced paramagnetic resonance techniques, namely electron-nuclear double resonance (ENDOR) and electron spin-echo envelope modulation (ESEEM) spectroscopies, can help us understand how metal ions function in biological systems.
The National Academy of Sciences.
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12. Dielectrophoretic dynamic light-scattering (DDLS) spectroscopy
Dielectrophoretic dynamic light-scattering (DDLS) spectroscopy is presented. DDLS identifies macromolecules based on their dielectric, or polarizability, properties. DDLS measurements are carried out in an oscillating, nonuniform electric field. The field induces macromolecules to undergo dielectrophoretic motion, which is detected by the modulation in t
National Academy of Sciences.