Pereira, M, Leal CR, Parola AJ, Scheven UM.
2010.
Reversible Photorheology in Solutions of Cetyltrimethylammonium Bromide, Salicylic Acid, and trans-2,4,4 '-Trihydroxychalcone, 2010. Langmuir. 26:16715-16721.
AbstractWe show photorheology in aqueous solutions of weakly entangled wormlike micelles prepared with cetyltrimethylammonium bromide (CTAB), salicylic acid (HSal), and dilute amounts of the photochromic multistate compound trans-2,4,4'-trihydroxychalcone (Ct). Different chemical species of Ct are associated with different colorations and propensities to reside within or outside CTAB micelles. A light-induced transfer between the intra- and intermicellar space is used to alter the mean length of wormlike micelles and hence the rheological properties of the fluid, studied in steady-state shear Bow and in dynamic rheological measurements. Light-induced changes of fluid rheology are reversible by a the relaxation process. at relaxation rates which depend on pH and which are consistent with photochromic reversion rates measured by UV-vis absorption spectroscopy. Parameterizing viscoelostic rheological states by their effective relaxation time tau(c) and corresponding response modulus G(c), we find the light and dark states of the system to fall onto a characteristic state curve defined by comparable experiments conducted without photosensitive components. These reference experiments were prepared with the same concentration of CTAB, but different concentrations of HSal or sodium salicylote (NaSal), and tested at different temperatures.
Barbosa, PC, Rodrigues LC, Silva MM, Smith MJ, Parola AJ, Pina F, Pinheiro C.
2010.
Solid-state electrochromic devices using pTMC/PEO blends as polymer electrolytes, 2010. Electrochimica Acta. 55:1495-1502.
AbstractFlexible, transparent and self-supporting electrolyte films based on poly(trimethylene carbonate)/poly(ethylene oxide) (p(TMC/PEO) interpenetrating networks doped with LiClO(4) were prepared by the solvent casting technique. These novel solid polymer electrolyte (SPE) systems were characterized by measurements of conductivity, cyclic voltammetry, differential scanning calorimetry and thermogravimetry. The incorporation of solid electrolytes as components of electrochromic devices can offer certain operational advantages in real-world applications. In this study, all-solid-state electrochromic cells were characterized, using Prussian blue (PB) and poly-(3,4-ethylenedioxythiophene)-poly(styrenesulfonate) (PEDOT) as complementary electrochromic compounds on poly(ethyleneterphthalate) (PET) coated with indium tin oxide (ITO) as flexible electrodes. Assembled devices with PET/ITO/PB/SPE/PEDOT/ITO/PET "sandwich-like" structure were assembled and successfully cycled between light and dark blue, corresponding to the additive optical transitions for PB and PEDOT electrochromic layers. The cells required long cycle times (>600 s) to reach full color switch and have modest stability towards prolonged cycling tests. The use of short duration cycling permitted the observation of changes in the coloration-bleaching performance in cells with different electrolyte compositions. (C) 2009 Elsevier Ltd. All rights reserved.
Neves, P, Pereira CCL, Paz FAA, Gago S, Pillinger M, Silva CM, Valente AA, Romao CC, Goncalves IS.
2010.
Cyclopentadienyl molybdenum dicarbonyl eta(3)-allyl complexes as catalyst precursors for olefin epoxidation. Crystal structures of Cp ' Mo(CO)(2)(eta(3)-C3H5) (Cp ' = eta(5)-C5H4Me, eta(5)-C5Me5). Journal of Organometallic Chemistry. 695:2311-2319., Number 21
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Abrantes, M, Neves P, Antunes MM, Gago S, Almeida Paz FA, Rodrigues AE, Pillinger M, Goncalves IS, Silva CM, Valente AA.
2010.
Microwave-assisted molybdenum-catalysed epoxidation of olefins. Journal of Molecular Catalysis a-Chemical. 320:19-26., Number 1-2
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