Resonance Raman
Mostrando 1-12 de 160 artigos, teses e dissertações.
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1. Near-Infrared Luminescence from Visible-Light-Sensitized Ruthenium(II)-Neodymium(III) Heterobimetallic Bridged Complexes Containing Alkoxy(silyl) Functional Groups
New infrared emitting d-f (ruthenium(II)-neodymium(III)) heterobimetallic complexes with alkoxy(silyl) functional groups have been prepared. Visible excitation evidenced energy transfer processes from the ruthenium(II) donor to neodymium(III) acceptors leading to infrared emission. Energy transfer rates (kEnT) and efficiency of energy transfer (ηEnT) are, r
J. Braz. Chem. Soc.. Publicado em: 2020-04
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2. UNRAVELING THE SOLVATOCHROMISM OF A TRIARYLMETHANE DYE BY RESONANCE RAMAN SPECTROSCOPY
The effect of the solvent on the electronic properties of the triarylmethane dye rosolic acid (RA) is investigated by means of UV-VIS and resonance Raman (RR) spectroscopies. The comparison of the solvatochromic behavior of both neutral and dianionic species of RA in acetonitrile, dimethylsulfoxide, and methanol illustrates the effect of polarity and hydroge
Quím. Nova. Publicado em: 05/12/2019
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3. SPECTROSCOPIC CHARACTERIZATION OF PEDOT:PSS CONDUCTING POLYMER BY RESONANCE RAMAN AND SERRS SPECTROSCOPIES
Poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonate) (PEDOT:PSS) synthesis was monitored by resonance Raman (RR) and surface-enhanced resonance Raman scattering (SERRS) spectroscopies and both the oxidation of the polymer and the effects of chain length were assessed by vibrational analysis. It was supported by theoretical models of oligomers, with charge
Quím. Nova. Publicado em: 05/12/2019
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4. EFEITOS DA TEMPERATURA NOS ESPECTROS RAMAN DOS POLÍMEROS CONDUTORES PEDOT E MEH-PPV
The present work shows the temperature dependence of the Raman spectra of two conjugated polymers: poly[2-methoxy-5-(2-ethylhexyloxy)-1,4-phenylenevinylene] (MEH-PPV) and poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonate) (PEDOT:PSS). In situ resonance Raman spectra of PEDOT from 77 to 423 K at 633 nm and of MEH-PPV from 77 to 473 K at 785 nm suggest th
Quím. Nova. Publicado em: 05/12/2019
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5. RAMAN STUDIES OF BIS(PHENYLTERPYRAZINE)IRON(II) AND SUPRAMOLECULAR SPECIES WITH PENTACYANIDOFERRATE(II) IONS
The chemistry and spectroscopy of the iron(II) phenylterpyrazine complex, [Fe(phtpz)2]2+, were investigated in comparison with the analogous phenylterpyridine species, Fe(phtpy)2]2+, and the results indicated a strong electronic delocalization on the Fe(II) terimine chromophore encompassing the lateral pyrazyl groups. The delocalized nature of the molecular
Quím. Nova. Publicado em: 05/12/2019
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6. BIOSSENSORES PLASMÔNICOS BASEADOS EM ESPALHAMENTO RAMAN INTENSIFICADO POR SUPERFÍCIE UTILIZANDO NANOBASTÕES DE OURO
There is still a significant need for low cost, fast and trustworthy diagnostic devices based on biosensors, which may impact positively for applications in developing countries. Localized surface plasmon resonance (LSPR) based biosensors have been taken as powerful alternative to deal with the above limitations. The local electromagnetic field enhancement c
Quím. Nova. Publicado em: 05/12/2019
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7. Gold Nanoparticles and [PEDOT-Poly(D,L-Lactic Acid)] Composite: Synthesis, Characterization and Application to H2O2 Sensing
Biocompatible electrochemical devices are challenging to develop due to the toxicity of many advanced electrode materials and the difficulty to degrade the discarded material. Few recent advances were made in the synthesis of conducting biodegradable composites of polymers for electrode materials. In this article we describe the synthesis of two new inorgani
J. Braz. Chem. Soc.. Publicado em: 21/10/2019
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8. Influence of graphene oxide on ‘in situ’ preparation of nanocomposites with polyvinyl butyral
ABSTRACT In this work, polyvinyl butyral (PVB) nanocomposites reinforced with 0.5 to 2.5 wt% of graphene oxide (GO) were synthesized via ‘in situ’ polymerization. PVB was obtained by condensation of hydroxyl groups of polyvinyl alcohol (PVA) with butyraldehyde (BU) Thermogravimetric analyzes (TGA) showed the increase in the thermal conductivity of the na
Matéria (Rio J.). Publicado em: 16/09/2019
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9. Exploring the metallochromic behavior of pentacyanidoferrates in visual, electronic and Raman spot tests
Abstract: Pentacyanidoferrate(II) complexes of aromatic N-heterocycles, such as 4-cyanopyridine, exhibit characteristic colors and strong metallochromism associated with the donor-acceptor interactions of the metal ions with the cyanide ligands. In the presence of transition metal ions insoluble polymeric complexes are formed, displaying bright yellow, red,
An. Acad. Bras. Ciênc.. Publicado em: 25/04/2019
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10. New trends in plasmonic (bio)sensing
Abstract The strong enhancement and localization of electromagnetic field in plasmonic systems have found applications in many areas, which include sensing and biosensing. In this paper, an overview will be provided of the use of plasmonic phenomena in sensors and biosensors with emphasis on two main topics. The first is related to possible ways to enhance t
An. Acad. Bras. Ciênc.. Publicado em: 2018
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11. Spectroscopic Characterization of Charge Transfer Complexes of TCNE with Aromatic Amines - The First Step of Tricyanovinylation Reaction
The first step of electrophilic aromatic substitution reactions generally involves the formation of charge transfer complexes. Tetracyanoethylene (TCNE) in the presence of aromatic amines forms π-type complexes that subsequently lead to tricyanovinylation reaction. Although this kind of reaction was investigated in the past, the spectroscopic characterizati
J. Braz. Chem. Soc.. Publicado em: 2017-09
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12. Optical and Structural Studies of Mn2+ Doped SbPO4-ZnO-PbO Glasses
New glass compositions in the system 1-x(SbPO4-ZnO-PbO)-xMnO (with 0 ≤ x ≤ 20 in mol%) were prepared by melt-quenching methodology. Thermal, structural and optical properties of the new glasses were systematically studied by means of differential scanning calorimetry (DSC), UV-Vis and Raman spectroscopy, fluorescence and electronic paramagnetic resonance
J. Braz. Chem. Soc.. Publicado em: 2015-12