Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 2 de 2
Filtrar
Mais filtros

Base de dados
Ano de publicação
Tipo de documento
Intervalo de ano de publicação
1.
J Fluoresc ; 32(4): 1509-1516, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35522344

RESUMO

Optical and photophysical properties of 6-substituted-1,2,4-Triazine fluorescent derivative dye doped in silicate based sol-gel, homopolymer of methyl methacrylate (PMMA), and copolymer (MMA/diethylene glycol dimethacrylate) (DEGDMA) were investigated. The pores of different hosts and caging of the dye were found to effect on the parameters such as molar absorptivity, cross sections of singlet-singlet electronic absorption and emission spectra, excited state lifetime, quantum yield of fluorescence. The dipole moment of electronic transition, the length of attenuation and oscillator strength of electronic transition from So → S1 have been calculated. The dye was pumped with different powers using 3rd harmonic Nd: YAG laser of 355 nm and pulse duration 8 ns, with repetition rate 10 Hz. Good photo stability for dye was attained. After 55,000 pumping pulses of (10 mJ/pulse), the photo-stabilities were decreased to 53%, 48%, and 45% of the initial ASE of dye in sol gel, PMMA, and Co-polymer respectively. The dye in sol-gel matrix showed improvement of photo stability compared with those in organic polymeric matrices.

2.
Spectrochim Acta A Mol Biomol Spectrosc ; 232: 118145, 2020 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-32066064

RESUMO

The optical properties of a visible absorption range6-Substituted-1, 2, 4-Triazine mono glucosyl fluorescent derivative dye, such as absorption spectra, emission spectra in different solvents, were experimentally investigated. As well, some important photo physical parameters such as extinction coefficient (ε), cross-sections of the absorption (σa) and the emission (σe), quantum yield (фf), fluorescence lifetime, oscillator strength (f), the dipole moment (µ), decay rate radiative constant (kr), energy yield of fluorescence (Ef) and the length of attenuation Λ (λ) were assessed. The ground-state (µg) and excited-state (µe) dipole moments by solvatochromic correlations method were reported. The dye amplified spontaneous emission (ASE) of 2 × 10-4M with different input pumping energies of a continuous wave blue diode laser (λ = 450 nm) was studied. Photostability of dye was observed that was decreased to 53% of its initial energy by pumping with 100 mW of diode laser after exposure to 120 min.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA