Excited State
Mostrando 1-12 de 313 artigos, teses e dissertações.
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1. Temperature Dependent Emission Properties of ReI Tricarbonyl Complexes with Dipyrido-Quinoxaline and Phenazine Ligands
In this work, the emission properties of fac-[Re(CO)3(NN)(py)]+, NN = 1,10-phenanthroline (phen), dipyrido[3,2-f:2’,3’-h]quinoxaline (dpq) and dipyrido[3,2-a:2’3’-c]phenazine (dppz); py = pyridine were investigated in different temperatures, ranging from 80 to 300 K, and in different solvent mixtures and in polymethyl methacrylate. The changes observ
Journal of the Brazilian Chemical Society. Publicado em: 2022
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2. Complexes with Furyl-Substituted 3-Hydroxychromone: Synthesis, Characterization and Fluorescence Studies
2-(2-Furyl)-3-hydroxychromone (HL) reacts with MII ions in the formation of quadratic [Cu(L)2] (3), octahedral [M(L)2(OH2)2] (M = Co (1), Ni (2), Zn (4), Mn (5)) and seesaw [M(L)2] (M = Sn (6), Pb (7)) complexes. Recrystallization of complexes 1-3 in presence of pyridine lead to [M(L)2(py)2] (1a-3a) aducts. All compounds were characterized by Fourier transfo
J. Braz. Chem. Soc.. Publicado em: 2021-08
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3. RECENTES APLICAÇÕES DO ORGANOFOTOCATALISADOR 1,2,3,5-TETRAQUIS(CARBAZOL-9-IL)-4,6-DICIANOBENZENO EM TRANSFORMAÇÕES QUÍMICAS
Ruthenium and iridium polypyridine complexes are among the most employed photocatalysts described in literature. The broad applicability is due to the redox potentials and long half-life times of the excited state which these molecules presented. The pursuit for metal-free alternatives has been intensified in the last few years, therefore, many organic fluor
Quím. Nova. Publicado em: 2021-03
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4. Shortcomings in the training program of medical residency during the COVID-19 pandemic in Brazil. How will they be repaired?
Ruthenium and iridium polypyridine complexes are among the most employed photocatalysts described in literature. The broad applicability is due to the redox potentials and long half-life times of the excited state which these molecules presented. The pursuit for metal-free alternatives has been intensified in the last few years, therefore, many organic fluor
Rev. Bras. Ginecol. Obstet.. Publicado em: 2021-03
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5. Where’s the Spin? A DFT Study of Mixed-Valence Cyanide-Bridged Ruthenium Polypyridines
This article discusses the use of density functional theory (DFT) calculations in classifying and characterizing bimetallic ruthenium mixed-valence systems in terms of their electronic localization/delocalization degree. A standard B3LYP/LanL2DZ methodology including integral equation formalism-polarizable continuum model (IEF-PCM) solvent model is evaluated
J. Braz. Chem. Soc.. Publicado em: 2020-11
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6. Mackie B. Corra para ser feliz: como a corrida salvou minha vida. Rio de Janeiro: Harper Collins; 2019.
This article discusses the use of density functional theory (DFT) calculations in classifying and characterizing bimetallic ruthenium mixed-valence systems in terms of their electronic localization/delocalization degree. A standard B3LYP/LanL2DZ methodology including integral equation formalism-polarizable continuum model (IEF-PCM) solvent model is evaluated
Ciênc. saúde coletiva. Publicado em: 2020-11
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7. JUDD-OFELT ANALYSIS OF Tb3+ AND UPCONVERSION STUDY IN Yb3+-Tb3+ CO-DOPED CALIBO GLASSES
We report on the study of the spectroscopic properties in Ytterbium-Terbium (Yb3+-Tb3+) co-doped calcium lithium borate (CaLiBO) glasses, with the study’s focus being on the upconversion process. Intensity parameters Ωλ for CaLiBO:Tb3+ are determined by the Judd-Ofelt method to be Ω2 = 15.5 × 10-20 cm2, Ω4 = 1.90 × 10-20 cm2 and Ω6 = 3.69 × 10-20 c
Quím. Nova. Publicado em: 2020-02
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8. Water-Soluble Benzazole Dyes Fluorescent by ESIPT: Structural Characterization, Photophysical Properties and Its Application as a Probe for Direct Staining of Helminths
A series of four water-soluble benzazole dyes that emit fluorescence by the excited state intramolecular proton transfer (ESIPT) mechanism were structurally characterized by Fourier transform infrared spectroscopy (FTIR), 1H and 13C nuclear magnetic resonance (NMR) attached proton test (APT) and mass spectrometry. Their photophysical properties were systemat
J. Braz. Chem. Soc.. Publicado em: 2019-03
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9. Pirates vs. Press Gangs: The Battle for the Atlantic
Resumo Os piratas instigam a imaginação coletiva desde quando saqueavam navios mercantes e lutavam por embarcações no Oceano Atlântico, durante a Idade da Vela. Não obstante, os piratas também contribuem para ilustrar um processo por vezes subestimado no estudo do desenvolvimento dos Estados e Impérios modernos: a luta entre atores estatais e não es
História. Publicado em: 31/01/2019
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10. Synthesis, Photophysical and Electrochemical Properties of Novel D-π-D and D-π-A Triphenylamino-Chalcones and β-Arylchalcones
A series of triphenylamino (TPA)-chalcones and triphenylamino-β-arylchalcones, displaying either D-π-D or D-π-A architecture, were synthesized through aldol condensations and Heck reactions. The chalcone derivatives display intense absorption bands ranging from 389 to 432 nm and molar extinction coefficients of ca. 105 L mol-1 cm-1 corresponding to π-π*
J. Braz. Chem. Soc.. Publicado em: 2019-01
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11. Photoluminescence of Solvent-Selected Fluorescent Moieties in MEH-PPV Solutions and Films
In this work, we examined how photoluminescence in poly[2-methoxy-5-(2-ethylhexyloxy)-1,4-phenylenevinylene] (MEH-PPV) is affected by morphology, dictated by the mode of preparation. For that, MEH-PPV dilute solutions in good and non-solvents, thick cast films with poly[methylmethacrylate] (PMMA) as inert matrix and spin-coated thin films were prepared. Thes
J. Braz. Chem. Soc.. Publicado em: 2018-03
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12. Brazilian Bioluminescent Beetles: Reflections on Catching Glimpses of Light in the Atlantic Forest and Cerrado
ABSTRACT Bioluminescence - visible and cold light emission by living organisms - is a worldwide phenomenon, reported in terrestrial and marine environments since ancient times. Light emission from microorganisms, fungi, plants and animals may have arisen as an evolutionary response against oxygen toxicity and was appropriated for sexual attraction, predation
An. Acad. Bras. Ciênc.. Publicado em: 2018