Search Results - "Lopez Hilfiker, Felipe"

Fine particle pH and the partitioning of nitric acid during winter in the northeastern United States by Guo, Hongyu, Sullivan, Amy P., Campuzano‐Jost, Pedro, Schroder, Jason C., Lopez‐Hilfiker, Felipe D., Dibb, Jack E., Jimenez, Jose L., Thornton, Joel A., Brown, Steven S., Nenes, Athanasios, Weber, Rodney J.

“…Particle pH is a critical but poorly constrained quantity that affects many aerosol processes and properties, including aerosol composition, concentrations,…”
Get full text

An Iodide-Adduct High-Resolution Time-of-Flight Chemical-Ionization Mass Spectrometer: Application to Atmospheric Inorganic and Organic Compounds by Lee, Ben H, Lopez-Hilfiker, Felipe D, Mohr, Claudia, Kurtén, Theo, Worsnop, Douglas R, Thornton, Joel A

“…A high-resolution time-of-flight chemical-ionization mass spectrometer (HR-ToF-CIMS) using Iodide-adducts has been characterized and deployed in several…”
Get full text

Molecular identification of organic vapors driving atmospheric nanoparticle growth by Mohr, Claudia, Thornton, Joel A., Heitto, Arto, Lopez-Hilfiker, Felipe D., Lutz, Anna, Riipinen, Ilona, Hong, Juan, Donahue, Neil M., Hallquist, Mattias, Petäjä, Tuukka, Kulmala, Markku, Yli-Juuti, Taina

“…Particles formed in the atmosphere via nucleation provide about half the number of atmospheric cloud condensation nuclei, but in many locations, this process…”
Get full text

Ambient observations of dimers from terpene oxidation in the gas phase: Implications for new particle formation and growth by Mohr, Claudia, Lopez‐Hilfiker, Felipe D., Yli‐Juuti, Taina, Heitto, Arto, Lutz, Anna, Hallquist, Mattias, D'Ambro, Emma L., Rissanen, Matti P., Hao, Liqing, Schobesberger, Siegfried, Kulmala, Markku, Mauldin, Roy L., Makkonen, Ulla, Sipilä, Mikko, Petäjä, Tuukka, Thornton, Joel A.

“…We present ambient observations of dimeric monoterpene oxidation products (C16–20HyO6–9) in gas and particle phases in the boreal forest in Finland in spring…”
Get full text

The role of chlorine in global tropospheric chemistry by Wang, Xuan, Jacob, Daniel J, Eastham, Sebastian D, Sulprizio, Melissa P, Zhu, Lei, Chen, Qianjie, Alexander, Becky, Sherwen, Tomas, Evans, Mathew J, Lee, Ben H, Haskins, Jessica D, Lopez-Hilfiker, Felipe D, Thornton, Joel A, Huey, Gregory L, Liao, Hong

“…We present a comprehensive simulation of tropospheric chlorine within the GEOS-Chem global 3-D model of oxidant–aerosol–halogen atmospheric chemistry. The…”
Get full text

Chemical feedbacks weaken the wintertime response of particulate sulfate and nitrate to emissions reductions over the eastern United States by Shah, Viral, Jaeglé, Lyatt, Thornton, Joel A., Lopez-Hilfiker, Felipe D., Lee, Ben H., Schroder, Jason C., Campuzano-Jost, Pedro, Jimenez, Jose L., Guo, Hongyu, Sullivan, Amy P., Weber, Rodney J., Green, Jaime R., Fiddler, Marc N., Bililign, Solomon, Campos, Teresa L., Stell, Meghan, Weinheimer, Andrew J., Montzka, Denise D., Brown, Steven S.

“…Sulfate ( SO 4 2 − ) and nitrate ( NO 3 − ) account for half of the fine particulate matter mass over the eastern United States. Their wintertime…”
Get full text

High Upward Fluxes of Formic Acid from a Boreal Forest Canopy by Schobesberger, Siegfried, Lopez-Hilifiker, Felipe D., Taipale, Ditte, Millet, Dylan B., D'Ambro, Emma L., Rantala, Pekka, Mammarella, Ivan, Zhou, Putian, Wolfe, Glenn M., Lee, Ben H., Boy, Michael, Thornton, J. A.

“…Eddy covariance fluxes of formic acid, HCOOH, were measured over a boreal forest canopy in spring/summer 2014. The HCOOH fluxes were bidirectional but mostly…”
Get full text

Estimating the contribution of organic acids to northern hemispheric continental organic aerosol by Yatavelli, Reddy L. N., Mohr, Claudia, Stark, Harald, Day, Douglas A., Thompson, Samantha L., Lopez-Hilfiker, Felipe D., Campuzano-Jost, Pedro, Palm, Brett B., Vogel, Alexander L., Hoffmann, Thorsten, Heikkinen, Liine, Äijälä, Mikko, Ng, Nga L., Kimmel, Joel R., Canagaratna, Manjula R., Ehn, Mikael, Junninen, Heikki, Cubison, Michael J., Petäjä, Tuukka, Kulmala, Markku, Jayne, John T., Worsnop, Douglas R., Jimenez, Jose L.

“…Using chemical ionization mass spectrometry to detect particle‐phase acids and aerosol mass spectrometry (AMS) measurements from Colorado, USA, and two studies…”
Get full text

Enhanced formation of isoprene‐derived organic aerosol in sulfur‐rich power plant plumes during Southeast Nexus by Xu, Lu, Middlebrook, Ann M., Liao, Jin, Gouw, Joost A., Guo, Hongyu, Weber, Rodney J., Nenes, Athanasios, Lopez‐Hilfiker, Felipe D., Lee, Ben H., Thornton, Joel A., Brock, Charles A., Neuman, J. Andrew, Nowak, John B., Pollack, Ilana B., Welti, Andre, Graus, Martin, Warneke, Carsten, Ng, Nga Lee

“…We investigate the effects of anthropogenic sulfate on secondary organic aerosol (SOA) formation from biogenic isoprene through airborne measurements in the…”
Get full text

Contribution of Nitrated Phenols to Wood Burning Brown Carbon Light Absorption in Detling, United Kingdom during Winter Time by Mohr, Claudia, Lopez-Hilfiker, Felipe D., Zotter, Peter, Prévôt, André S. H., Xu, Lu, Ng, Nga L., Herndon, Scott C., Williams, Leah R., Franklin, Jonathan P., Zahniser, Mark S., Worsnop, Douglas R., Knighton, W. Berk, Aiken, Allison C., Gorkowski, Kyle J., Dubey, Manvendra K., Allan, James D., Thornton, Joel A.

“…We show for the first time quantitative online measurements of five nitrated phenol (NP) compounds in ambient air (nitrophenol C6H5NO3, methylnitrophenol…”
Get full text

Constraining the sensitivity of iodide adduct chemical ionization mass spectrometry to multifunctional organic molecules using the collision limit and thermodynamic stability of iodide ion adducts by Lopez-Hilfiker, Felipe D., Iyer, Siddarth, Mohr, Claudia, Lee, Ben H., D'Ambro, Emma L., Kurtén, Theo, Thornton, Joel A.

“…The sensitivity of a chemical ionization mass spectrometer (ions formed per number density of analytes) is fundamentally limited by the collision frequency…”
Get full text

Heterogeneous N2O5 Uptake During Winter: Aircraft Measurements During the 2015 WINTER Campaign and Critical Evaluation of Current Parameterizations by McDuffie, Erin E., Fibiger, Dorothy L., Dubé, William P., Lopez‐Hilfiker, Felipe, Lee, Ben H., Thornton, Joel A., Shah, Viral, Jaeglé, Lyatt, Guo, Hongyu, Weber, Rodney J., Michael Reeves, J., Weinheimer, Andrew J., Schroder, Jason C., Campuzano‐Jost, Pedro, Jimenez, Jose L., Dibb, Jack E., Veres, Patrick, Ebben, Carly, Sparks, Tamara L., Wooldridge, Paul J., Cohen, Ronald C., Hornbrook, Rebecca S., Apel, Eric C., Campos, Teresa, Hall, Samuel R., Ullmann, Kirk, Brown, Steven S.

“…Nocturnal dinitrogen pentoxide (N2O5) heterogeneous chemistry impacts regional air quality and the distribution and lifetime of tropospheric oxidants. Formed…”
Get full text

Widespread Pollution From Secondary Sources of Organic Aerosols During Winter in the Northeastern United States by Shah, Viral, Jaeglé, Lyatt, Jimenez, Jose L., Schroder, Jason C., Campuzano‐Jost, Pedro, Campos, Teresa L., Reeves, John M., Stell, Meghan, Brown, Steven S., Lee, Ben H., Lopez‐Hilfiker, Felipe D., Thornton, Joel A.

“…Secondary organic aerosol (SOA) from pollution sources is thought to be a minor component of organic aerosol (OA) and fine particulate matter beyond the urban…”
Get full text

Online molecular characterization of fine particulate matter in Port Angeles, WA: Evidence for a major impact from residential wood smoke by Gaston, Cassandra J., Lopez-Hilfiker, Felipe D., Whybrew, Lauren E., Hadley, Odelle, McNair, Fran, Gao, Honglian, Jaffe, Daniel A., Thornton, Joel A.

“…We present on-line molecular composition measurements of wintertime particulate matter (PM) during 2014 using an iodide-adduct high-resolution, time-of-flight…”
Get full text

Electrocautery smoke exposure and efficacy of smoke evacuation systems in minimally invasive and open surgery: a prospective randomized study by Kocher, Gregor J., Koss, Abigail R., Groessl, Michael, Schefold, Joerg C., Luedi, Markus M., Quapp, Christopher, Dorn, Patrick, Lutz, Jon, Cappellin, Luca, Hutterli, Manuel, Lopez-Hilfiker, Felipe D., Al-Hurani, Mohammad, Sesia, Sergio B.

“…Worldwide, health care professionals working in operating rooms (ORs) are exposed to electrocautery smoke on a daily basis. Aims of this study were to…”
Get full text

Airborne Observations of Reactive Inorganic Chlorine and Bromine Species in the Exhaust of Coal‐Fired Power Plants by Lee, Ben H., Lopez‐Hilfiker, Felipe D., Schroder, Jason C., Campuzano‐Jost, Pedro, Jimenez, Jose L., McDuffie, Erin E., Fibiger, Dorothy L., Veres, Patrick R., Brown, Steven S., Campos, Teresa L., Weinheimer, Andrew J., Flocke, Frank F., Norris, Gary, O'Mara, Kate, Green, Jaime R., Fiddler, Marc N., Bililign, Solomon, Shah, Viral, Jaeglé, Lyatt, Thornton, Joel A.

“…We present airborne observations of gaseous reactive halogen species (HCl, Cl2, ClNO2, Br2, BrNO2, and BrCl), sulfur dioxide (SO2), and nonrefractory fine…”
Get full text

ClNO2 Yields From Aircraft Measurements During the 2015 WINTER Campaign and Critical Evaluation of the Current Parameterization by McDuffie, Erin E., Fibiger, Dorothy L., Dubé, William P., Lopez Hilfiker, Felipe, Lee, Ben H., Jaeglé, Lyatt, Guo, Hongyu, Weber, Rodney J., Reeves, J. Michael, Weinheimer, Andrew J., Schroder, Jason C., Campuzano‐Jost, Pedro, Jimenez, Jose L., Dibb, Jack E., Veres, Patrick, Ebben, Carlena, Sparks, Tamara L., Wooldridge, Paul J., Cohen, Ronald C., Campos, Teresa, Hall, Samuel R., Ullmann, Kirk, Roberts, James M., Thornton, Joel A., Brown, Steven S.

“…Nitryl chloride (ClNO2) plays an important role in the budget and distribution of tropospheric oxidants, halogens, and reactive nitrogen species. ClNO2 is…”
Get full text

Wintertime Gas‐Particle Partitioning and Speciation of Inorganic Chlorine in the Lower Troposphere Over the Northeast United States and Coastal Ocean by Haskins, Jessica D., Jaeglé, Lyatt, Shah, Viral, Lee, Ben H., Lopez‐Hilfiker, Felipe D., Campuzano‐Jost, Pedro, Schroder, Jason C., Day, Douglas A., Guo, Hongyu, Sullivan, Amy P., Weber, Rodney, Dibb, Jack, Campos, Teresa, Jimenez, Jose L., Brown, Steven S., Thornton, Joel A.

“…The formation of photolabile chlorine reservoirs depend on how much chloride is available in the particle to react, which requires the chlorine partitioning to…”
Get full text

Field intercomparison of the gas/particle partitioning of oxygenated organics during the Southern Oxidant and Aerosol Study (SOAS) in 2013 by Thompson, Samantha L., Yatavelli, Reddy L. N., Stark, Harald, Kimmel, Joel R., Krechmer, Jordan E., Day, Douglas A., Hu, Weiwei, Isaacman-VanWertz, Gabriel, Yee, Lindsay, Goldstein, Allen H., Khan, M. Anwar H., Holzinger, Rupert, Kreisberg, Nathan, Lopez-Hilfiker, Felipe D., Mohr, Claudia, Thornton, Joel A., Jayne, John T., Canagaratna, Manjula, Worsnop, Douglas R., Jimenez, Jose L.

“…We present results of the first intercomparison of real-time instruments for gas/particle partitioning of organic species. Four recently-developed instruments…”
Get full text

NOx Lifetime and NOy Partitioning During WINTER by Kenagy, Hannah S., Sparks, Tamara L., Ebben, Carlena J., Wooldrige, Paul J., Lopez‐Hilfiker, Felipe D., Lee, Ben H., Thornton, Joel A., McDuffie, Erin E., Fibiger, Dorothy L., Brown, Steven S., Montzka, Denise D., Weinheimer, Andrew J., Schroder, Jason C., Campuzano‐Jost, Pedro, Day, Douglas A., Jimenez, Jose L., Dibb, Jack E., Campos, Teresa, Shah, Viral, Jaeglé, Lyatt, Cohen, Ronald C.

“…Although urban NOx lifetimes have been examined extensively during summertime conditions, wintertime NOx chemistry has been comparatively less studied. We use…”
Get full text