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Energy Transfer from Fluorene Based Conjugated Polyelectrolytes to Onchain and ...
Marques, Ana T.; Pinto, Sara M. A.; Monteiro, Carlos J. P.; Melo, J. Sérgio Seixas de; Burrows, Hugh D.; Scherf, Ullrich; Calvete, Mário J. F.A new water soluble fluorene-based polyelectrolyte containing on-chain porphyrin units has been synthesized via Suzuki coupling, for use in optoelectronic devices. The material consist of a random copolymer of poly{1,4-phenylene-[9,9-bis(4-phenoxy butylsulfonate)]fluorene-2,7-diyl} (PBS-PFP) and a 5,15-diphenylporphyrin (DPP). The energy transfer process between the PBS-PFP units and the porphyrin has been inve...
Interaction between Poly(9,9-bis(6′-N,N,N-trimethylammonium)hexyl)fluorene phen...
Monteserín, María; Burrows, Hugh D.; Valente, Artur J. M.; Mallavia, Ricardo; Paolo, Roberto E. Di; Maçanita, António L.; Tapia, María J.The interaction between three poly(9,9-bis(6-N,N,N-trimethylammonium)hexyl)fluorene phenylene) bromide (HTMA-PFP) samples of different molecular weights (Mn = 14.5, 30.1 and 61.3 kg/mol) and both dsDNA and ssDNA secondary structures has been studied using UV−visible absorption and fluorescence spectroscopies (including steady-state, time-resolved, and anisotropy measurements for the latter), viscosity, and elec...
Solubilization of Poly1,4-phenylene-[9,9-bis(4-phenoxy-butylsulfonate)] fluoren...
Burrows, Hugh D.; Tapia, María J.; Fonseca, Sofia M.; Pradhan, Swapna; Scherf, Ullrich; Silva, Cláudia L.; Pais, Alberto A. C. C.; Valente, Artur J. M.In the presence of the nonionic alkyloxyethylene surfactant n-dodecylpentaoxyethylene glycol ether (C12E5), the anionic conjugated polyelectrolyte (CPE) poly1,4-phenylene-[9,9-bis(4-phenoxy-butylsulfonate)]fluorene-2,7-diyl (PBS-PFP) dissolves in water, leading to a blue shift in fluorescence and dramatic increases in fluorescence quantum yields above the surfactant critical micelle concentration (cmc). No sign...
Density functional theory study of the oxoperoxo vanadium(V) complexes of glyco...
Justino, Licínia L. G.; Ramos, M. Luísa; Kaupp, Martin; Burrows, Hugh D.; Fiolhais, Carlos; Gil, Victor M. S.The DFT B3LYP/SBKJC method has been used to calculate the gas-phase optimized geometries of the glycolate oxoperoxo vanadium(V) complexes [V2O2(OO)2(gly)2]2-, [V2O3(OO)(gly)2]2- and [VO(OO)(gly)(H2O)]-. The 51V, 17O, 13C and 1H chemical shifts have been calculated for the theoretical geometries in all-electron DFT calculations at the UDFT-IGLO-PW91 level and have been subsequently compared with the experimental...
Conformational Studies of Poly(9,9-dialkylfluorene)s in Solution Using NMR Spec...
Justino, Licínia L. G.; Ramos, M. Luísa; Abreu, Paulo E.; Carvalho, Rui A.; Sobral, Abilio J. F. N.; Scherf, Ullrich; Burrows, Hugh D.Relationships have been obtained between intermonomer torsional angle and NMR chemical shifts (1H and 13C) for isolated chains of two of the most important poly(9,9-dialkylfluorenes), poly[9,9-bis(2-ethylhexyl)fluorene-2,7-diyl] (PF2/6) and the copolymer poly(9,9-dioctylfluorene-co-[2,1,3]benzothiadiazole-4,7-diyl) (F8BT), using DFT calculations. The correlations provide a model for NMR spectral data interpreta...
Density functional theory study of the oxoperoxo vanadium(V) complexes of glyco...
Justino, Licínia L. G.; Ramos, M. Luísa; Kaupp, Martin; Burrows, Hugh D.; Fiolhais, Carlos; Gil, Victor M. S.The DFT B3LYP/SBKJC method has been used to calculate the gas-phase optimized geometries of the glycolate oxoperoxo vanadium(V) complexes [V2O2(OO)2(gly)2]2-, [V2O3(OO)(gly)2]2- and [VO(OO)(gly)(H2O)]-. The 51V, 17O, 13C and 1H chemical shifts have been calculated for the theoretical geometries in all-electron DFT calculations at the UDFT-IGLO-PW91 level and have been subsequently compared with the experimental...
Synthesis, spectroscopy, photophysics and thermal behaviour of stilbene-based t...
Gigante, Bárbara; Esteves, M. Alexandra; Pires, N.; Davies, Matthew L.; Douglas, Peter; Fonseca, Sofia M.; Burrows, Hugh D.; Pina, JoãoNovel stilbene-based triarylamines with dehydroabietic acid methyl ester moieties have been synthesised by palladium catalysed C–N coupling reactions. The presence of the bulky dehydroabietic acid group increases solubility, hinders crystallisation and permits their sublimation while preserving their electronic and optical characteristics. This makes them good candidates for various molecular electronic applica...
Using Lanthanides as Probes for Polyelectrolyte-Metal Ion Interactions. Hydrati...
Costa, Diana; Ramos, M. Luísa; Burrows, Hugh D.; Tapia, M. José; Miguel, Maria da Graçahttp://www.sciencedirect.com/science/article/B6TFM-4SWFNW8-1/1/aadd2972e76576ca7bf5c347abd5a683
Aggregation and micellization of sodium dodecyl sulfate in the presence of Ce(I...
Valente, Artur J. M.; Burrows, Hugh D.; Cruz, Sandra M. A.; Pereira, Rui F. P.; Ribeiro, Ana C. F.; Lobo, Victor M. M.Aggregation properties of sodium dodecyl sulfate (SDS) in the presence of cerium(III) chloride, at various temperatures (298.15-323.15 K) have been measured by the electrical conductance technique. The experimental data on aqueous solutions as a function of SDS concentration show the presence of two inflexion points indicating the presence of two distinct interaction mechanisms: the first, occurring at SDS conc...
Mean distance of closest approach of ions: Lithium salts in aqueous solutions
Ribeiro, Ana C. F.; Lobo, Victor M. M.; Burrows, Hugh D.; Valente, Artur J. M.; Amado, Ana M.; Sobral, Abílio J. F. N.; Teles, Ana S. N.Numerical values for the mean distance of closest approach of ions, "a", for lithium salts in aqueous solutions are presented and discussed. These values were obtained from both experimental activity and diffusion coefficients, and estimated by using different theoretical approaches. ; http://www.sciencedirect.com/science/article/B6TGR-4RR1NKM-1/1/b8d3cdac33991c5424d567940bc0c3a6
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