Search Results - "Knighton, W. B."

Simulation of semi-explicit mechanisms of SOA formation from glyoxal in aerosol in a 3-D model by Knote, C, Hodzic, A, Jimenez, J. L, Volkamer, R, Orlando, J. J, Baidar, S, Brioude, J, Fast, J, Gentner, D. R, Goldstein, A. H, Hayes, P. L, Knighton, W. B, Oetjen, H, Setyan, A, Stark, H, Thalman, R, Tyndall, G, Washenfelder, R, Waxman, E, Zhang, Q

“…New pathways to form secondary organic aerosol (SOA) have been postulated recently. Glyoxal, the smallest dicarbonyl, is one of the proposed precursors. It has…”
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Characterization of submicron particles influenced by mixed biogenic and anthropogenic emissions using high-resolution aerosol mass spectrometry: results from CARES by Setyan, A, Zhang, Q, Merkel, M, Knighton, W. B, Sun, Y, Song, C, Shilling, J. E, Onasch, T. B, Herndon, S. C, Worsnop, D. R, Fast, J. D, Zaveri, R. A, Berg, L. K, Wiedensohler, A, Flowers, B. A, Dubey, M. K, Subramanian, R

“…An Aerodyne high resolution time-of-flight aerosol mass spectrometer (HR-ToF-AMS) was deployed during the Carbonaceous Aerosols and Radiative Effects Study…”
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Measurements of volatile organic compounds at a suburban ground site (T1) in Mexico City during the MILAGRO 2006 campaign: measurement comparison, emission ratios, and source attribution by Bon, D. M., Ulbrich, I. M., de Gouw, J. A., Warneke, C., Kuster, W. C., Alexander, M. L., Baker, A., Beyersdorf, A. J., Blake, D., Fall, R., Jimenez, J. L., Herndon, S. C., Huey, L. G., Knighton, W. B., Ortega, J., Springston, S., Vargas, O.

“…Volatile organic compound (VOC) mixing ratios were measured with two different instruments at the T1 ground site in Mexico City during the Megacity Initiative:…”
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Chemistry of new particle growth in mixed urban and biogenic emissions – insights from CARES by Setyan, A, Song, C, Merkel, M, Knighton, W. B, Onasch, T. B, Canagaratna, M. R, Worsnop, D. R, Wiedensohler, A, Shilling, J. E, Zhang, Q

“…Regional new particle formation and growth events (NPEs) were observed on most days over the Sacramento and western Sierra foothills area of California in June…”
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Investigation of the correlation between odd oxygen and secondary organic aerosol in Mexico City and Houston by Wood, E. C., Canagaratna, M. R., Herndon, S. C., Onasch, T. B., Kolb, C. E., Worsnop, D. R., Kroll, J. H., Knighton, W. B., Seila, R., Zavala, M., Molina, L. T., DeCarlo, P. F., Jimenez, J. L., Weinheimer, A. J., Knapp, D. J., Jobson, B. T., Stutz, J., Kuster, W. C., Williams, E. J.

“…Many recent models underpredict secondary organic aerosol (SOA) particulate matter (PM) concentrations in polluted regions, indicating serious deficiencies in…”
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Short-term variation in near-highway air pollutant gradients on a winter morning by Durant, J L, Ash, C A, Wood, E C, Herndon, S C, Jayne, J T, Knighton, W B, Canagaratna, M R, Trull, J B, Brugge, D, Zamore, W, Kolb, C E

“…Quantification of exposure to traffic-related air pollutants near highways is hampered by incomplete knowledge of the scales of temporal variation of pollutant…”
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Distribution, magnitudes, reactivities, ratios and diurnal patterns of volatile organic compounds in the Valley of Mexico during the MCMA 2002 & 2003 field campaigns by Velasco, E., Lamb, B., Westberg, H., Allwine, E., Sosa, G., Arriaga-Colina, J. L., Jobson, B. T., Alexander, M. L., Prazeller, P., Knighton, W. B., Rogers, T. M., Grutter, M., Herndon, S. C., Kolb, C. E., Zavala, M., de Foy, B., Volkamer, R., Molina, L. T., Molina, M. J.

“…A wide array of volatile organic compound (VOC) measurements was conducted in the Valley of Mexico during the MCMA-2002 and 2003 field campaigns. Study sites…”
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Particulate Emissions Measured During the TCEQ Comprehensive Flare Emission Study by Fortner, E. C, Brooks, W. A, Onasch, T. B, Canagaratna, M. R, Massoli, P, Jayne, J. T, Franklin, J. P, Knighton, W. B, Wormhoudt, J, Worsnop, D. R, Kolb, C. E, Herndon, S. C

“…During the 2010 TCEQ Comprehensive Flare Emission Study, a suite of instruments deployed on the Aerodyne Mobile Laboratory performed online measurements of…”
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A case study of ozone production, nitrogen oxides, and the radical budget in Mexico City by Wood, E. C., Herndon, S. C., Onasch, T. B., Kroll, J. H., Canagaratna, M. R., Kolb, C. E., Worsnop, D. R., Neuman, J. A., Seila, R., Zavala, M., Knighton, W. B.

“…Observations at a mountain-top site within the Mexico City basin are used to characterize ozone production and destruction, nitrogen oxide speciation and…”
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Application of positive matrix factorization to on-road measurements for source apportionment of diesel- and gasoline-powered vehicle emissions in Mexico City by Thornhill, D. A., Williams, A. E., Onasch, T. B., Wood, E., Herndon, S. C., Kolb, C. E., Knighton, W. B., Zavala, M., Molina, L. T., Marr, L. C.

“…The goal of this research is to quantify diesel- and gasoline-powered motor vehicle emissions within the Mexico City Metropolitan Area (MCMA) using on-road…”
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Evaluation of mobile emissions contributions to Mexico City's emissions inventory using on-road and cross-road emission measurements and ambient data by Zavala, M., Herndon, S. C., Wood, E. C., Onasch, T. B., Knighton, W. B., Marr, L. C., Kolb, C. E., Molina, L. T.

“…Mobile emissions represent a significant fraction of the total anthropogenic emissions burden in the Mexico City Metropolitan Area (MCMA) and, therefore, it is…”
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Characterization of on-road vehicle emissions in the Mexico City Metropolitan Area using a mobile laboratory in chase and fleet average measurement modes during the MCMA-2003 field campaign by Zavala, M., Herndon, S. C., Slott, R. S., Dunlea, E. J., Marr, L. C., Shorter, J. H., Zahniser, M., Knighton, W. B., Rogers, T. M., Kolb, C. E., Molina, L. T., Molina, M. J.

“…A mobile laboratory was used to measure on-road vehicle emission ratios during the MCMA-2003 field campaign held during the spring of 2003 in the Mexico City…”
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Vehicle fleet emissions of black carbon, polycyclic aromatic hydrocarbons, and other pollutants measured by a mobile laboratory in Mexico City by Jiang, M., Marr, L. C., Dunlea, E. J., Herndon, S. C., Jayne, J. T., Kolb, C. E., Knighton, W. B., Rogers, T. M., Zavala, M., Molina, L. T., Molina, M. J.

“…Black carbon (BC) and polycyclic aromatic hydrocarbons (PAHs) are of concern due to their effects on climate and health. The main goal of this research is to…”
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Comparison of emissions from on-road sources using a mobile laboratory under various driving and operational sampling modes by Zavala, M., Herndon, S. C., Wood, E. C., Jayne, J. T., Nelson, D. D., Trimborn, A. M., Dunlea, E., Knighton, W. B., Mendoza, A., Allen, D. T., Kolb, C. E., Molina, M. J., Molina, L. T.

“…Mobile sources produce a significant fraction of the total anthropogenic emissions burden in large cities and have harmful effects on air quality at multiple…”
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Quantitatively resolving mixtures of isobaric compounds using chemical ionization mass spectrometry by modulating the reactant ion composition by Fortner, E. C., Knighton, W. B.

“…Acrolein (C3H4O) and 1‐butene (C4H8) can both be individually detected by proton transfer chemical ionization mass spectrometry (CI‐MS). However, because these…”
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Resolving interferences in negative mode ion mobility spectrometry using selective reactant ion chemistry by Daum, Keith A., Atkinson, David A., Ewing, Robert G., Knighton, W.B., Grimsrud, Eric P.

“…During the investigation of the degradation products of 2,4,6-trinitrotoluene (TNT) using ion mobility spectrometry (IMS), 2,4-dichlorophenoxyacetic acid…”
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Response to the Letter on Wormhoudt, J.; Wood, E.; Knighton, W.; Kolb, C.; Herndon, S.; Olaguer, E. 2015. Vehicle emissions of radical precursors and related species observed in the 2009 SHARP campaign; J. Air Waste Manage. Assoc. 65: 699-706 by Wormhoudt, J., Wood, E. C., Knighton, W. B., Kolb, C. E., Herndon, S.C.

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Vehicle emissions of radical precursors and related species observed in the 2009 SHARP campaign by Wormhoudt, J., Wood, E. C., Knighton, W. B., Kolb, C. E., Herndon, S. C., Olaguer, E. P.

“…The 2009 Study of Houston Atmospheric Radical Precursors (SHARP) field campaign had several components that yielded information on the primary vehicular…”
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Adaptation of a proton transfer reaction mass spectrometer instrument to employ NO+ as reagent ion for the detection of 1,3-butadiene in the ambient atmosphere by Knighton, W. B., Fortner, E. C., Herndon, S. C., Wood, E. C., Miake-Lye, R. C.

“…A proton transfer reaction mass spectrometer (PTR‐MS) instrument was adapted to employ NO+ as a chemical reagent ion without any hardware changes by switching…”
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Reaction of Chloride Ion with Isopropyl Bromide at Atmospheric Pressure by Ion Mobility Spectrometry by Sahlstrom, K. E, Knighton, W. B, Grimsrud, E. P

“…The SN2 nucleophilic displacement reaction of chloride ion with isopropyl bromide (i-PrBr) has been studied in nitrogen buffer gas at a pressure of 640 Torr…”
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