Browsing by Subject "kinetics"

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    A radiotracer study of the adsorption behavior of aqueous Ba2+ ions on nanoparticles of zero-valent iron
    (2007) Çelebi O.; Üzüm, C.; Shahwan, T.; Erten H.N.
    Recently, iron nanoparticles are increasingly being tested as adsorbents for various types of organic and inorganic pollutants. In this study, nanoparticles of zero-valent iron (NZVI) synthesized under atmospheric conditions were employed for the removal of Ba2+ ions in a concentration range 10-3 to 10-6 M. Throughout the study, 133Ba was used as a tracer to study the effects of time, concentration, and temperature. The obtained data was analyzed using various kinetic models and adsorption isotherms. Pseudo-second-order kinetics and Dubinin-Radushkevich isotherm model provided the best correlation with the obtained data. Observed thermodynamic parameters showed that the process is exothermic and hence enthalpy-driven. © 2007 Elsevier B.V. All rights reserved.
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    Transmission Near-Field Scanning Optical Microscopy Investigation on Cellular Uptake Behavior of Iron Oxide Nanoparticles
    (2012) Zhang, Y.; Kyle J.R.; Penchev, M.; Yazdanpanah V.; Yu J.; Li, Y.; Yang, M.; Budak G.; Özbay, Ekmel; Ozkan, M.; Ozkan, C.S.
    Cellular uptake behavior of iron oxide nanoparticles is investigated using a transmission near-field scanning optical microscopy (NSOM) without the need of fluorescent labeling. By using the transmission NSOM system, we could simultaneously explore the near-field optical analysis of the cell interior and record the topographic information of the cell surface. The cell endocytosis of iron oxide nanoparticles by normal breast MCF10A cells is first studied by this transmission NSOM system, and this dual functional nanoscale-resolution microscopy shows the capability of mapping the spatial localization of nanoparticles in/outside cell surface without the need of fluorescence labeling. Nanoscale optical signature patterns for iron oxide nanoparticle-loaded vesicles inside the cells were observed and analyzed. © Springer Science+Business Media, LLC 2012.