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Full-Text Articles in Chemistry
A Preliminary Examination Of An In Situ Dual Dye Approach To Measuring Light Fluxes In Lotic Systems, Elizabeth C. Minor, Elizabeth James, Jay A. Austin, Veronica Nelson, Ryan Lusk, Kenneth Mopper
A Preliminary Examination Of An In Situ Dual Dye Approach To Measuring Light Fluxes In Lotic Systems, Elizabeth C. Minor, Elizabeth James, Jay A. Austin, Veronica Nelson, Ryan Lusk, Kenneth Mopper
Chemistry & Biochemistry Faculty Publications
Light is a critical parameter in aquatic ecosystems, affecting primary production and in situ photochemistry. However, measuring light exposure for suspended particles or dissolved components in a dynamic water column can be challenging with existing Eulerian approaches. Here, we assess the simultaneous deployment of two dyes differing in photolability (rhodamine WT and fluorescein) as a Lagrangian measure of sunlight exposure in a lotic system. Fluorescein is sensitive to light exposure; rhodamine WT is relatively photostable. We examined dye fluorescence at various pH, salinity, and temperature conditions. We also tested dye photolability as a function of pH and wavelength range. In …
Role Of Extractable And Residual Organic Matter Fractions On Sorption Of Phenanthrene In Sediments, Yulong Zhang, Yong Ran, Jingdong Mao
Role Of Extractable And Residual Organic Matter Fractions On Sorption Of Phenanthrene In Sediments, Yulong Zhang, Yong Ran, Jingdong Mao
Chemistry & Biochemistry Faculty Publications
Two sediments were demineralized and sequentially fractionated into extracted fractions [free lipid (FL), bound lipid (BL) and lignin (LG)] and residual fractions [free lipid free (FLF), bound lipid free (BLF) and lignin free (LGF)]. The sorption isotherms of phenanthrene (Phen) were examined to evaluate the importance of various fractions on sorption. A lignin extraction procedure was for the first time applied to separate the lignin or degraded lignin fraction from sediment organic matter (SOM). The extracted LG was similar to model lignin in terms of elemental ratios and sorption behavior. FL and LG fractions were quite important, as their contents …
Interaction Mechanism Of Benzene And Phenanthrene In Condensed Organic Matter: Importance Of Adsorption (Nanopore-Filling), Ke Sun, Yong Ran, Yu Yang, Baoshan Xing, Jingdong Mao
Interaction Mechanism Of Benzene And Phenanthrene In Condensed Organic Matter: Importance Of Adsorption (Nanopore-Filling), Ke Sun, Yong Ran, Yu Yang, Baoshan Xing, Jingdong Mao
Chemistry & Biochemistry Faculty Publications
Although microporosity and surface area of natural organic matter (NOM) are crucial to mechanistic evaluation of the sorption process for nonpolar organic contaminants (NOCs), they have wrongly been estimated by the N2 adsorption technique. Nuclear magnetic resonance spectroscopy (13C NMR), and benzene, carbon dioxide, and nitrogen adsorption techniques were used to characterize structural and surface properties for different condensed NOM samples, which were related to the sorption behavior of phenanthrene (Phen). It was found that the revised Freundlich model by taking the chemical activity into account can well describe the isotherms for benzene and Phen. The benzene …