To achieve a better balance between the refractive index and Abbe number, the thiol-functionalized polyhedral oligomeric silsesquioxane (POSS−SH) was incorporated as both nanoreinforcement and cross-linking reagent into high-refractive index polythiourethane (PTU). The influences of the POSS−SH on the microstructures and properties of PTU were investigated. It is found that all the nanocomposites exhibited a dense network structure and high structural homogeneity even at the POSS−SH loading up to 10 wt %. Besides great improvements in the thermal stability and mechanical property, the nanocomposite containing 1.5 wt % POSS− SH revealed a slight reduction in the refractive index from 1.6568 for neat PTU to 1.6557 but a significant increase in the Abbe number from 28 to 35, accompanied by excellent optical transparency. These results indicate that the covalent incorporation of bifunctional POSS− SH into the PTU network will be helpful for the rational design of advanced optical and optoelectronic materials.
A new chemiluminescence (CL) method is proposed for the determination of quinine sulphate, which is based on the dichloromethane solvent extraction of the ion-pair complex of tetrachloroaurate (III) with quinine sulphate, and luminol CL detection in a reversed micellar medium formed by the cation surfactant cetyltrimethylammonium bromide in a dichloromethane-cyclohexane (3:7, v/v)-water (0.35 mol/L Na2CO3 buffer solution, pH 11.5). The ion-pair complex of tetrachloroaurate (III) with quinine sulphate produced an analytical CL signal when it entered the reversed micellar water pool. In optimum conditions, CL intensities are proportional to the concentrations of the studied drug over the range 0.015-10 microg/mL, with a detection limit of 1.5 ng/mL. The relative standard deviation (RSD) is 1.38% for 2.5 microg/mL quinine sulphate (n=11). The method has been applied to the determination of the studied drug in biological fluids, with satisfactory results.
1,1′-Bichrysene-2,2′-diol and its thiophene analogs, 6,6′-biphenanthro-[1,2- b]thiophene-7,7′-diols, as a series of novel π-expanded chrysene-/phenanthro[1,2- b]thiophene-based axially chiral molecules are synthesized from 1,1′-bi-2-naphthols with key steps including a Suzuki coupling, a Wittig reaction, and acid-mediated cyclization.
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