Browsing by Subject "Oxygen"
Now showing items 1-3 of 3
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Fluorescence quenching method for monitoring oxygen diffusion into PS/CNT composite films
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Publisher and Date:(Elsevier Science SA, 2013)Oxygen permeabilities of nanocomposite films consisting of multi wall carbon nanotubes (MWNT) and polystyrene (PS) were determined to investigate the oxygen diffusion depending on MWNT and temperature. A method which is based on quenching of an excited phosphorescent by oxygen was applied for the measurements. The composite films were prepared from mixtures of (MWNT) and surfactant-free pyrene (P)-labeled (PS) latexes of various compositions at room temperature. These films were then annealed at ...
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Measurement of oxygen diffusion in PS/PNIPAM films using fluorescence quenching
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Publisher and Date:(Taylor & Francis Ltd, 2015)The diffusion of oxygen into pyrene labelled polystyrene (PS) latex/poly(N-isopropylacrylamide) (PNIPAM) composite films (PS/PNIPAM) was studied based on PS content with the use of fluorescence quenching method. Fluorescence experiments were carried out on composite films containing pyrene as a sensor dye. The Stern-Volmer equation for fluorescence quenching is combined with Fick's law for diffusion to derive mathematical expressions. Diffusion coefficients (D) were produced and found to be decreased ...
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Oxygen Diffusion into Multiwalled Carbon Nanotube Doped Polystrene Latex Films Using Fluorescence Technique
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Publisher and Date:(Springer/Plenum Publishers, 2013)This study examines the oxygen diffusion into polystyrene (PS) latex/multiwalled carbon nanotube (MWNT) nanocomposite films (PS/MWNT) consisting of various amounts of MWNT via steady state fluorescence technique (SSF). PS/MWNT films were prepared from the mixture of MWNT and pyrene (P)-labeled PS latexes at various compositions at room temperature. These films were then annealed at 170 A degrees C above glass transition (T-g) temperature of PS. Fluorescence quenching measurements were performed ...