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HERO ID
193347
Reference Type
Journal Article
Title
Aggregation of titanium dioxide nanoparticles: Role of a fulvic acid
Author(s)
Domingos, RF; Tufenkji, N; Wilkinson, KJ
Year
2009
Is Peer Reviewed?
1
Journal
Environmental Science & Technology
ISSN:
0013-936X
EISSN:
1520-5851
Volume
43
Issue
5
Page Numbers
1282-1286
DOI
10.1021/es8023594
URL
http://pubs.acs.org/doi/abs/10.1021/es8023594
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Abstract
The increasing use of nanomaterials in consumer products has led to increased concerns about their potential environmental and health impacts. To better understand the transport, fate, and behavior of nanoparticles in aquatic systems, it is essential to understand their interactions with different components of natural waters including natural organic matter over a broad range of physicochemical conditions. Fluorescence correlation spectroscopy was used to determine the diffusion coefficients of TiO2 nanoparticles having a nominal size of 5 nm. The effects of a various concentrations of the Suwannee River Fulvic Acid (SRFA) and the roles of pH and ionic strength were evaluated. Aggregation of the bare TiO2 nanoparticles increased for pH values near the zero point of charge. At any given pH, an increase in ionic strength generally resulted in increased aggregation. Furthermore, conditions which favored adsorption of the SRFA resulted in less aggregation of the TiO2 nanoparticles, presumably due to increased steric repulsion. Under the conditions studied here, nanoparticle dispersions were often stable for environmentally relevant conditions of SRFA, pH, and ionic strength, suggesting that in the natural environment, TiO2 dispersion might occur to a greater extent than expected.
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Nanoscale Silver
External Review Draft
Final Case Study
Introduction to Document, Silver and Nanoscale Silver
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