TY - JOUR
T1 - Chemical composition of atmospheric nanoparticles formed from nucleation in Tecamac, Mexico
T2 - Evidence for an important role for organic species in nanoparticle growth
AU - Smith, Jim N.
AU - Dunn, M. J.
AU - VanReken, T. M.
AU - Iida, K.
AU - Stolzenburg, Mark R
AU - McMurry, Peter H
AU - Huey, L. G.
PY - 2008/2/28
Y1 - 2008/2/28
N2 - We report Thermal Desorption Chemical Ionization Mass Spectrometer (TDCIMS) measurements of the composition of ambient 10-33 nm diameter particles formed from nucleation on 16 March 2006 in Tecamac, Mexico during the Megacity Initiative: Local and Global Research Observations (MILAGRO) field study. On this day, nucleated particles contained far more organics than sulfates: average ion molar ratios with measurement uncertainties for nitrate, organics and sulfur species were 6±2%, 84±5%, and 10±1%, respectively. The measured organic species include nitrogen-containing organic compounds, organic acids, and hydroxy organic acids. Independent calculations show that sulfuric acid condensation could have accounted for only 10±2% of the growth that was observed on this day, which is consistent with the TDCIMS measurements of composition. It follows that organic compounds play a dominant role the high growth rates that were observed.
AB - We report Thermal Desorption Chemical Ionization Mass Spectrometer (TDCIMS) measurements of the composition of ambient 10-33 nm diameter particles formed from nucleation on 16 March 2006 in Tecamac, Mexico during the Megacity Initiative: Local and Global Research Observations (MILAGRO) field study. On this day, nucleated particles contained far more organics than sulfates: average ion molar ratios with measurement uncertainties for nitrate, organics and sulfur species were 6±2%, 84±5%, and 10±1%, respectively. The measured organic species include nitrogen-containing organic compounds, organic acids, and hydroxy organic acids. Independent calculations show that sulfuric acid condensation could have accounted for only 10±2% of the growth that was observed on this day, which is consistent with the TDCIMS measurements of composition. It follows that organic compounds play a dominant role the high growth rates that were observed.
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U2 - 10.1029/2007GL032523
DO - 10.1029/2007GL032523
M3 - Article
AN - SCOPUS:43449119484
SN - 0094-8276
VL - 35
JO - Geophysical Research Letters
JF - Geophysical Research Letters
IS - 4
M1 - L04808
ER -
