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Chemistry

LSU Doctoral Dissertations

Theses/Dissertations

2013

EPFRs

Articles 1 - 2 of 2

Full-Text Articles in Physical Sciences and Mathematics

Environmentally Persistent Free Radicals (Epfrs) In Pm₂.₅ : Their Contribution To Hydroxyl Radical Formation And Atmospheric Transformation, William Micheal Gehling, Jr. Jan 2013

Environmentally Persistent Free Radicals (Epfrs) In Pm₂.₅ : Their Contribution To Hydroxyl Radical Formation And Atmospheric Transformation, William Micheal Gehling, Jr.

LSU Doctoral Dissertations

Previous research demonstrated environmentally persistent free radicals (EPFRs) will form on particulate surfaces under combustion conditions (temperature range of 150-400 °C) from reactions of organic precursors with redox-active transition metals. With an understanding of how these EPFRs form, it is necessary to determine how they behave in a natural environment after emission. To better understand this, the nature of EPFRs in ambient PM2.5 under simulated atmospheric conditions was investigated. Ambient PM2.5 samples were collected at a roadside ambient monitoring site near heavy interstate traffic and major industrial activity. The EPFR concentration and general radical structure were determined with EPR spectroscopy. …


Experimental And Computational Studies Of Environmentally Persistent Free Radicals (Epfrs) Formation, Lucy W. Kiruri Jan 2013

Experimental And Computational Studies Of Environmentally Persistent Free Radicals (Epfrs) Formation, Lucy W. Kiruri

LSU Doctoral Dissertations

The first part of the thesis investigates the use of theoretical quantum calculations for the study of EPFRs as the initial and fundamental step in the formation of polychlorinated dibenzo-p-dioxin and dibenzofuran. The computational model comprised of density functionals (B3LYP, PBE1PBE, and M06) and two types of basis set namely: LANL2DZ for all atoms and GEN (LANL2DZ for metals and aug-cc-pVDZ for non-metals). Full mechanisms of EPFRs formation over (CuO)1-8, and aluminum oxide clusters were studied. The most stable intermediates and products have been determined and compared to available experimental data. In case of (CuO)1-8 clusters, the small clusters are …