Quantum Coherence
Mostrando 1-12 de 34 artigos, teses e dissertações.
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1. A Calix[4]arene-Functionalized Perylene Imide and Its Luminescence Properties
In this study, new perylene-derived molecules were synthesized as perylene-3,4,9,10-tetracarboxylic acid monoanhydride monopotassium carboxylate 1; N-(3-propanol)perylene-3,4,9,10-tetracarboxylic-3,4-(monoimide)anhydride-9,10-acid potassium carboxylate 2; 5,11,17,23-tetra(tert-butyl)-25,27-bis(3’-bromopropoxy)-26,28-(dihydroxy)calix[4]arene 3; 5,11,17,23-t
J. Braz. Chem. Soc.. Publicado em: 2020-11
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2. Copaifera multijuga, Copaifera pubiflora and Copaifera trapezifolia Oleoresins: Chemical Characterization and in vitro Cytotoxic Potential against Tumoral Cell Lines
Copaifera species (Fabaceae) comprises approximately 70 species of large trees, from which 16 can be found in Brazil. The oleoresins obtained from their trunk are widely used in Brazilian folk medicine, which display important antitumoral potential. Chemically, these oleoresins are mainly composed of a mixture of sesquiterpenes and diterpenes. In this paper
J. Braz. Chem. Soc.. Publicado em: 2020-08
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3. A New Steroidal Saponin from the Tubers of Ophiopogon japonicus and Its Protective Effect Against Cisplatin-Induced Renal Cell Toxicity
A new furostanol saponin, ophiopogonin T, was isolated from the tubers of Ophiopogon japonicus. Its structure was established by extensive spectroscopic techniques including 1D (1H and 13C) and 2D nuclear magnetic resonance (NMR) experiments (correlation spectroscopy (COSY), heteronuclear single quantum coherence (HSQC), heteronuclear multiple bond correlati
J. Braz. Chem. Soc.. Publicado em: 2016-04
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4. Detailed 1H and 13C NMR Spectral Data Assignment for Two Dihydrobenzofuran Neolignans
In this work we present a complete proton (1H) and carbon 13 (13C) nuclear magnetic resonance (NMR) spectral analysis of two synthetic dihydrofuran neolignans (±)-trans-dehydrodicoumarate dimethyl ester and (±)-trans-dehydrodiferulate dimethyl ester. Unequivocal assignments were achieved by 1H NMR, proton decoupled 13C (13C{1H}) NMR spectra, gradient-selec
J. Braz. Chem. Soc.. Publicado em: 2016-01
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5. Cytotoxic Alkaloids from Hippeastrum solandriflorum Lindl.
One new alkaloid, 2α-10bα-dihydroxy-9-O-demethylhomolycorine, in addition to seven others known alkaloids, and 5-(hydroxymethyl)furfural, piscidic acid and eucomic acid, were isolated from the bulbs of Hippeastrum solandriflorum. The structures of all compounds were determined using nuclear magnetic resonance (NMR) spectroscopic techniques: 1H NMR and 13C
J. Braz. Chem. Soc.. Publicado em: 2015-10
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6. O campo eletromagnético quantizado submetido a ruído e acoplado a um oscilador mecânico / The quantized electromagnetic field submitted to noise and coupled to a mechanical oscillator
In this project we will investigate the influence of noise in the process of interaction of radiation (quantized field) with the matter (mesoscopic mechanical system). We will consider the mode field confined in a cavity of high quality factor with a fixed mirror and one moving mirror, this treated as a mechanical oscillator susceptible to radiation pressure
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 14/05/2012
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7. Coerência quântica macroscópica em sistemas ferromagnéticos / Macroscopic quantum coherence in ferromagnetic systems
Por muitas décadas, fenômenos quânticos foram observados com partículas microscópicas, tais como átomos, elétrons e fótons. No entanto, avanços na fabricação e controle de sistemas físicos com dimensões extremamente reduzidas vêm permitindo a manifestação de eventos quânticos em proporções gigantescas. Por exemplo, existem evidências de s
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 29/08/2011
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8. Entangled Brownian particles / Particulas Brownianas emaranhadas
This work consists in a study of entanglement in open quantum systems, within the brownian particles model. The interest comes from the possibility of understanding the mechanisms that lead the environment to create or to keep entanglement between quantum systems and not only make them lose energy or coherence. We start by making a review of the meaning of e
Publicado em: 2009
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9. Decoherence and relaxation time in an ensemble of quantum dots / Tempos de relaxação e decoerencia em ensembles de pontos quanticos
Experimental measurements were carried out to determine the scales of the relaxation and decoherence time for the electronic spin as quantum bit. The structure of the exciton states was investigated with the objective to serve as intermediate states in the spin manipulation. The system studied for the implementation of the quantum computation is an ensemble
Publicado em: 2007
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10. DC electric field effects on the electron dynamics in double rectangular quantum dots
The effect of a dc electric field on the temporal evolution of an electron in a double rectangular quantum dot is explored in this work. In the framework of the effective mass approximation, first-order scattering rates for interaction between confined electron-''free'' electron and electron-longitudinal acoustic phonon at room temperature are calculated in
Brazilian Journal of Physics. Publicado em: 2006-09
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11. Coherent properties and rabi oscillations in two-level donor systems
Coherent properties and Rabi oscillations in two-level donor systems, under terahertz excitation, are theoretically investigated. Here we are concerned with donor states in bulk GaAs and GaAs - (Ga, Al)As quantum dots. We study confinement effects, in the presence of an applied magnetic field, on the electronic and on-center donor states in GaAs - (Ga, Al)As
Brazilian Journal of Physics. Publicado em: 2006-06
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12. Prediction of the amount of secondary structure of proteins using unassigned NMR spectra: a tool for target selection in structural proteomics
With the advent of structural genomics, the need for fast structural information about unknown proteins has increased. We describe a new methodology, based on 13C, 15N and ¹H chemical shift dispersion to predict the amount of secondary structure of unassigned proteins from their 15N- and/or 13C-edited heteronuclear single quantum coherence (HSQC) spectra. T
Genetics and Molecular Biology. Publicado em: 2006