Publicaciones 2011-2020

@article{RN207,
title = {Binding of Phenols with Amphipathic Cationic Polyelectrolytes},
author = { H. Rios and G.A. Collio and M. Urz\'{u}a and V. Vargas},
url = {/brokenurl#<Go to ISI>://WOS:000331602300006},
doi = {10.1080/00222348.2013.845067},
issn = {0022-2348},
year = {2014},
date = {2014-01-01},
journal = {Journal of Macromolecular Science Part B-Physics},
volume = {53},
number = {3},
pages = {428-439},
abstract = {The association of phenols, such as p-cresol, tribromophenol, and trichlorophenol, with several amphipathic poly (n-alkylmethyldiallylammonium) chlorides in aqueous solution was studied by ultrafiltration. The n-alkyl residues were octyl, decyl, and dodecyl and the binding degrees were significantly higher than those found with the hydrophilic poly (diallyldimethylammonium) chloride. The results agreed well with the Satake and Yang's treatment and Hill's empirical equation for the association process, thereby revealing, in both cases, an increasing cooperative effect as the polyelectrolyte side chain increased in length for the same phenol, and when the hydrophobic nature of the phenol increased for the same kind of polyelectrolyte. From the phenomenological association constants, the estimated molar standard free energies of association ranged from -19kJmol(-1), for the more hydrophilic phenoxide-polyelectrolyte pair, to -28kJmol(-1) for the more hydrophobic pairs. The main result is that the amphipathic nature of these polyelectrolytes makes them efficient systems to trap anionic contaminants, better than hydrophilic flocculants.},
keywords = {amphipathic aqueous-solution, association, binding, cooperative decyl, liquid-chromatography, micelles, partition-coefficients, phenols, polyelectrolytes, salts solubilization, sulfonates},
pubstate = {published},
tppubtype = {article}
}

@article{RN57,
title = {Sorption of Polybrominated Diphenyl Ethers in Biosolid Model Samples},
author = { J. Rivas and M.I. Toral and P. Richter},
url = {/brokenurl#<Go to ISI>://WOS:000305169800005},
doi = {10.4067/S0717-97072012000200005},
issn = {0717-9707},
year = {2012},
date = {2012-01-01},
journal = {Journal of the Chilean Chemical Society},
volume = {57},
number = {2},
pages = {1087-1090},
abstract = {Biosolid model samples (BMSs) were developed to study the capacity of various matrixes to adsorb polybrominated diphenyl ethers (PBDEs) as a function of their composition. A commercial standard reference samples for biosolids containing a certified amount of PBDEs is currently not available for extraction evaluation. Therefore, this study will allow for the selection of an appropriate concentration of PBDEs to produce a reference material for analytes associated with the matrix., The sorption of PBDEs increased clearly concomitantly with the amount of organic matter present in the model, revealing that organic matter rather than the inorganic fraction is mainly responsible for the analyte-matrix interaction. Hydrophobic interactions are predominant in the retention of PBDEs in the biosolid matrix because more hydrophobic congeners are generally sorbed to a higher extent than those that are less hydrophobic., In order to know the probable PBDE sorption mechanism on the model sample of biosolid, the Gibbs free energies were calculated using the Freundlich model, giving values between -8 and -10 kJ/mol. These results suggest that the sorption mechanism of the PBDEs is through physiosorption. Therefore, the Freundlich model should be satisfactory for describing the analyte behavior.},
keywords = {biosolid brominated developmental exposure, extraction feed, fish flame low-dose matter, microextraction, model organic organic-matter, partition-coefficients, pbde-99, pbdes, phase polychlorinated-biphenyls, retardants, sample, sorption, thyroid-hormone},
pubstate = {published},
tppubtype = {article}
}