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Full-Text Articles in Chemistry
Iron Speciation In Pm2.5 From Urban, Agriculture, And Mixed Environments In Colorado, Usa, Joseph R. Salazar, David J. Pfotenhauer, Frank Leresche, Fernando L. Rosario-Ortiz, Michael P. Hannigan, Sirine C. Fakra, Brian Majestic
Iron Speciation In Pm2.5 From Urban, Agriculture, And Mixed Environments In Colorado, Usa, Joseph R. Salazar, David J. Pfotenhauer, Frank Leresche, Fernando L. Rosario-Ortiz, Michael P. Hannigan, Sirine C. Fakra, Brian Majestic
Chemistry and Biochemistry: Faculty Scholarship
Atmospheric iron solubility varies depending on whether the particles are collected in rural or urban areas, with urban areas showing increased iron solubility. In this study, we investigate if the iron species present in different environments affects its ultimate solubility. Field data are presented from the Platte River Air Pollution and Photochemistry Experiment (PRAPPE), aimed at understanding the interactions between organic carbon and trace elements in atmospheric particulate matter (PM). 24-hr PM2.5 samples were collected during the summer and winter (2016–2017), at three different sites on the Eastern Colorado plains: an urban, agricultural, and a mixed site. Downtown Denver had …
Technical Note: Swift - A Fast Semi-Empirical Model For Polar Stratospheric Ozone Loss, M. Rex, S. Kremser, P. Huck, G. Bodeker, I. Wohltmann, M. L. Santee, P. F. Bernath
Technical Note: Swift - A Fast Semi-Empirical Model For Polar Stratospheric Ozone Loss, M. Rex, S. Kremser, P. Huck, G. Bodeker, I. Wohltmann, M. L. Santee, P. F. Bernath
Chemistry & Biochemistry Faculty Publications
An extremely fast model to estimate the degree of stratospheric ozone depletion during polar winters is described. It is based on a set of coupled differential equations that simulate the seasonal evolution of vortex-averaged hydrogen chloride (HCl), nitric acid (HNO3), chlorine nitrate (ClONO2), active forms of chlorine (ClOx = Cl+ClO+2ClOOCl) and ozone (O3) on isentropic levels within the polar vortices. Terms in these equations account for the chemical and physical processes driving the time rate of change of these species. Eight empirical fit coefficients associated with these terms are derived by iteratively fitting the equations …
Middle Atmospheric Changes Caused By The January And March 2012 Solar Proton Events, C. H. Jackman, C. E. Randall, V. L. Harvey, S. Wang, E. L. Fleming, M. López-Puertas, B. Funke, P. F. Bernath
Middle Atmospheric Changes Caused By The January And March 2012 Solar Proton Events, C. H. Jackman, C. E. Randall, V. L. Harvey, S. Wang, E. L. Fleming, M. López-Puertas, B. Funke, P. F. Bernath
Chemistry & Biochemistry Faculty Publications
The recent 23-30 January and 7-11 March 2012 solar proton event (SPE) periods were substantial and caused significant impacts on the middle atmosphere. These were the two largest SPE periods of solar cycle 24 so far. The highly energetic solar protons produced considerable ionization of the neutral atmosphere as well as HOx (H, OH, HO2) and NOx (N, NO, NO2). We compute a NOx production of 1.9 and 2.1 Gigamoles due to these SPE periods in January and March 2012, respectively, which places these SPE periods among the 12 largest in the past 50 yr. Aura Microwave Limb Sounder (MLS) …
Abnormal Vapor Densities, Minnie Elizabeth Rice
Abnormal Vapor Densities, Minnie Elizabeth Rice
Student and Lippitt Prize essays
This essay questions Italian chemist Avogadro’s hypothesis about vapor densities, ultimately coming to the conclusion that Avogadro’s law is open to objection.