Resonance Raman
Mostrando 13-24 de 160 artigos, teses e dissertações.
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13. Synthesis, Vibrational Spectroscopic and Thermal Properties of Oxocarbon Cross‑Linked Chitosan
In this work specimens of chitosan which have been cross-linked covalently and ionically with different oxocarbon and pseudo-oxocarbon anions have been synthesised and characterized using infrared and Raman spectroscopic techniques, solid state 13C nuclear magnetic resonance (NMR) and by thermogravimetry. According to the spectroscopic and thermal results, i
J. Braz. Chem. Soc.. Publicado em: 2015-06
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14. Kinetic Investigation of Thermal Formation Processes of SiOC Glasses Derived from C-Containing Hybrid Polymeric Networks
In this study, hybrid polymeric networks were prepared by hydrosilylation reaction as precursors to silicon oxycarbide (SiOC) glass. The polymeric networks were prepared from poly(methylsiloxane) (PMS) and divinylbenzene (DVB) in the 80:20 and 20:80 (PMS/DVB) compositions, with or without activated charcoal (AC), which was used as additional carbon source. F
J. Braz. Chem. Soc.. Publicado em: 2015-05
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15. Síntese e caracterização de misturas poliméricas condutoras para aplicação em membranas biodegradáveis e dispositivos eletroluminescentes / Synthesis and characterization of conducting polymeric blends for use in biodegradable membranes and electroluminescent devices
The electrical properties of some conducting polymers and their blends have contributed to the technological advancement in various areas such as medicine and microelectronics. Recently, photochemical synthesis and spinner techniques have been using to prepare polymeric blends with good conducting properties. In this study we report the preparation of conduc
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 02/08/2012
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16. Radial breathing mode resonance Raman cross-section analysis in single-walled carbon nanotubes
Amostras de nanotubos de carbono de parede única (SWNT) geralmente são compostas por uma mistura de um grande número de diferentes espécies de SWNTs, cujas diferentes propriedades podem ser determinadas a partir de um par de índices (n;m), ou, equivalentemente, pelo seu diâmetro e ângulo quiral (dt; ). Aqui, utilizamos a espectroscopia Raman ressonant
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 12/03/2012
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17. Spectroscopic study of molecular dynamics and packing in organic semiconductors / Estudo espectroscópico da dinâmica molecular e empacotamento em semicondutores orgânicos
In this dissertation we present a study of the molecular dynamics and packing in organics semiconductor with different conjugated chains lengths using a of multi-techniques approach, in particular, Nuclear Magnetic Resonance (NMR), Wide Angle X-ray Scattering (WAXS), Differential Scanning Calorimetry (DSC), Raman spectroscopy, UV-Vis absorption and fluoresce
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 22/07/2011
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18. Estudo da interação de nanotubos de carbono com substrato de quartzo cristalino
Single wall carbon nanotubes (SWNTs) are quasi-onedimensional structures consisting of a rolled up graphene nanoribbon. Due to their unusually large surface-to-volume ratio, SWNTs are strongly affected by the environment. Contact with a supporting substrate modifies their properties, and such interactions have been broadly studied as either a drawback or a s
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 24/03/2011
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19. Éxcitons em nanocristais de silício / Excitons in Silicon nanocrystals
As propriedades ópticas de nanocristais de silício (Si-ncs) têm sido extensivamente estudadas após a primeira demonstração em 1990 de fotoluminescência altamente eficiente em silício poroso. Apesar dos progressos no entendimento da natureza da alta eficiência da luminescência dos Si-ncs e da enorme versatilidade para aplicações optoeletrônicas,
Publicado em: 2010
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20. Estudo da interação elétron-fônon em nanotubos de carbono por Espectroscopia Raman Ressonante
In this work, we have used resonance Raman spectroscopy to the study of carbon nanotubes. We reviewed the literature concerning their structural, electronic and vibrational properties, emphasizing the role of many-body effects, particularly the electron-phonon interaction, on the latter two properties. We also reviewed how Raman spectroscopy can be applied t
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 01/09/2009
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21. Desenvolvimento de metodologias para o estudo do efeito Raman normal e ressonante utilizando modelos Ab initio dependentes do tempo / Development of methodologies for the study of normal and resonance Raman effect using Ab initio time-dependent models
In this work new methodologies for the calculation of absolute vibrational Raman intensities of gaseous systems are presented. In order to reduce the computational requirements in these calculations two families of compact basis functions were generated from the effective core potential valence basis sets SBKJC and Stuttgart-Cologne through the Sadlej s elec
Publicado em: 2009
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22. Interaction of SO2 with molecular and ionic species: Raman spectroscopy and theoretical calculations / Interação de SO2 com espécies iônicas e moleculares: espectrocopia raman e cálculos teóricos
In the present work molecular systems bearing the sulfur dioxide (SO2) as an electron acceptor species and several electron donor species as amines (aliphatic and aromatic), inorganic complexes and ionic liquids were investigated. Such complexes are commonly known as donor-acceptor complexes, and in particular, in the case of SO2 complexes are characterized
Publicado em: 2009
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23. Sínteses, caracterizações e estudo de pontos quânticos de calcogenetos de cádmio
CdS, CdSe, CdSxSe1-x and Cd1-xMnxS quantum dots were successfully grown in the glass matrix SNAB [40SiO2.30Na2CO3.1Al2O3.29B2O3 (mol%)] synthesized by the Fusion Method, when subjected to certain thermal treatment. The glass transition temperature (Tg) of the glass matrix SNAB was found by Differential Scanning Calorimetry (DSC) in order to set the temperatu
Publicado em: 2009
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24. Estudo da dopagem em nanotubos de carbono por espectroscopia Raman ressonante.
Doping of single wall carbon nanotubes with boron, nitrogen, phosphorous and sulfur was studied by resonance Raman spectroscopy. The doping atoms were inserted in the tube walls during synthesis, by using chemical vapor deposition, laser ablation and arc discharge methods. The analysis of the Raman spectra shows that the insertion of dopants generates tubes
Publicado em: 2009