CHEMISTRY AND STRUCTURE-LINKED PROPERTIES OF ORGANIC AEROSOL COMPOUNDS

• Sponsoring Institution: National Institute of Food and Agriculture
• Project Status: TERMINATED
• Funding Source: HATCH
• Reporting Frequency: Annual
• Accession No.: 1010513
• Project No.: CA-D-ETX-2345-H
• Project Start Date: Oct 1, 2016
• Project End Date: Sep 30, 2021

Project Director
Nguyen, TR.

Recipient Organization
UNIVERSITY OF CALIFORNIA, DAVIS
410 MRAK HALL
DAVIS,CA 95616-8671

Performing Department
Environmental Toxicology

Non Technical Summary
The microscopic particles in the air we breathe make up only a tiny amount of the atmosphere (a million times less by weight than carbon dioxide), but they are disproportionately important. Particles change how the Earth reflects sunlight (as you can see from a red sunset) and they change how clouds are formed - both of which impact the Earth's climate. The impact on clouds also effect weather patterns, such as rainfall and (some scientists suspect) tropical storm formation. Small (or "fine") particles are also linked to negative health effects in humans. The effects can be as small as irritation, and as large as early death, depending on the type of particles and dose. That is why the EPA controls fine particles as "criteria pollutants." Most fine particles are formed in the atmosphere from chemical reactions, not directly emitted. And most of them are "organic", meaning they are made out of the Carbon building blocks that come from living things like people and plants, instead of "inorganic" like the minerals from rocks. Our research asks the following questions:1. "How are atmospheric organic particles formed in areas where human pollution mixes with the vapors from plants?" - This is important because in these areas, the amount of particles that are made is several times more than what we can predict. This means that we don't understand the processes as well as we should.2. "How do atmospheric organic particles change in the atmosphere?" - Particles float around for days. During that time, they are exposed to sunlight and other conditions. We know that they change, or "age", but we don't quite understand the aging chemistry. We want to know about this process because the chemicals that we study when the particle is "fresh" may not be there any longer as it travels in the atmosphere.3. "How can we improve the measurement tools to measure the chemicals in the air and in the particles?" - Perhaps the first question should be "why" do we need to improve the measurements? This is because a large fraction of organics in the particles are so hard to detect that we are pretty much blind to them. In order to study the science, we have to upgrade the tools.4. "Which organic chemicals in particles are linked to negative health effects in humans?" - This is a big question that we don't expect to answer by ourselves. We will use the tools we have and our knowledge of atmospheric chemistry to identify new toxicants and link them to specific health effects, but much more study will need to be done to really nail down the "reasons" why some particles are bad for human health.Our group explores these questions using a highly-controlled simulated atmosphere (a big transparent bag) that has only one reaction going at a time. This is because the real atmosphere is filled to too many reactions that confound the chemistry we try to study. We also have to build a few custom scientific tools before we start to answer the questions, but our group is confident that we have the expertise to do this. We believe that in five years, we'll be able to discuss the questions outlined in 1 - 4 in a meaningful way, and, hopefully, be in a position to ask new questions.

Animal Health Component

0%

Research Effort Categories

Basic

70%

Applied

20%

Developmental

10%

Classification

Knowledge Area (KA)	Subject of Investigation (SOI)	Field of Science (FOS)	Percent
132	0410	2000	25%
133	0430	2010	25%
141	0440	2020	25%
404	0499	1150	25%

Knowledge Area
133 - Pollution Prevention and Mitigation; 132 - Weather and Climate; 404 - Instrumentation and Control Systems; 141 - Air Resource Protection and Management;

Subject Of Investigation
0430 - Climate; 0499 - Atmosphere, general/other; 0410 - Air; 0440 - Solar radiation;

Field Of Science
2010 - Physics; 2020 - Engineering; 2000 - Chemistry; 1150 - Toxicology;

Keywords

particles

particulate matter

semivolatile

urban pollution

atmospheric chemistry

svoc

pm

environmental mass

spectrometry

cims

desi

air pollution

climate change

Goals / Objectives
1. Identify formation and "aging" pathways for organic PM and SVOC that involve sunlight, agricultural emissions (e.g., ammonia and amines), and urban emissions (e.g., NOx and SO2).2. Improve the characterization of organic PM components that contain peroxide moieties (analysis of organic acid, nitrogen- and sulfur-containing compounds will also be performed).3. Characterize the toxicological effects of "fresh" or "aged" organic PM

Project Methods
SVOC detection will use a custom chemical ionization mass spectrometer (CIMS) with a CF3O- reagent source. The CIMS is has a detection limit of 100 part per trillion and is sensitive to gas-phase organic acids, organic nitrates, organic peroxides, and other polar volatile compounds. The CIMS will be built as part of this project.Organic PM analysis will utilize a high-resolution linear-ion-trap Orbitrap instrument with and without HPLC separation. Fractionation based on HPLC-HR-MS will be performed after chromatogram is collected, on a standard C18 column. An additional analysis protocol will change the liquid ionization source to a surface technique, by building a new ionization stage based on the desorption electrospray techniques.Mass analysis will use a custom Labview protocol that de-isotopes, deconvolutes (by peak fitting), subtracts background, and assign using the exact mass of the elements and strict chemical valency rules.High-throughput preliminary analysis of mutigenicity and cytotoxicity will utilize commercial bacterial assays that rely on colorimetric and fluorescence determination. Analysis will utilize a UV-Vis spectrometer with microplate fluorescence analyzer.

Progress 10/01/16 to 09/30/21

Outputs
Target Audience:The target audience for this research include members of the public, regulatory agencies (such as Environmental Protection Agency and California Air Resources Board), the National Science Foundation, and atmospheric modelers who use the environmental data as inputs for their models. Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided?The project has provided opportunities for the professional development of four Environmental Toxicology undergraduate students (Helena Bayat, LamKam Chan, Amanda Burns, and Lillian Tran). Three of these undergraduate students have graduated and are all attending graduate or professional school. Lillian is still doing research as part of the lab. Two Chemistry undergraduate researchers (Karizza Abellar, Haley Cavenaugh-Fulton) were also trained as part of this project - they are now employed in industry. The project also provided training opportunities for one Ag Chem PhD student (Dr. Yichen Li), one Atmospheric Science masters student (Mr. Guy Burke) and one Forensics masters student (Ms. Khanh Nguyen). Dr. Li and Ms. Nguyen are now employed in industry, and Mr. Burke is now a physical scientist with the U.S. EPA. How have the results been disseminated to communities of interest?The project results have been disseminated in the form of conference and journal publications as described in the products section of annual reports. What do you plan to do during the next reporting period to accomplish the goals? Nothing Reported

Impacts
What was accomplished under these goals? The following lists our accomplishments over the 5 year period: * We published research which improved the scientific understanding of how smoldering woodsmoke fires affect air quality (PM and SVOC emissions), health (EC50 for cell death, AhR activity), and visibility (mass absorption coefficient). [Chan et al (2017)] *We published research which improved the scientific understanding of how biogenic hydrocarbons in the presence of urban NOx pollution affect air quality and climate. [Link et al., 2020, Cope et al., 2021, Bates et al., 2021a, Abellar et al., 2021, Bates et al., 2021b] *We published research which improved the scientific understanding of how PM in industrial cities in CA effect health. [D'Evelyn et al., 2017] * We published research which improved the scientific understanding chemical toxicity from vaping aerosols [Li et al., ES&T 2020, Li et al., CRT 2021, Li et al., CRT 2022 in review] *We developed a national open-access database for atmospheric chamber research in air quality and climate (icarus.ucdavis.edu)

Publications

• Type: Journal Articles Status: Published Year Published: 2021 Citation: Yichen Li, Amanda E. Burns, Lillian N. Tran, Karizza A. Abellar, Morgan Poindexter, Xiaohan Li, Amy K. Madl, Kent E. Pinkerton, Tran B. Nguyen*, Impact of e-Liquid Composition, Coil Temperature and Puff Topography on the Aerosol Chemistry of Electronic Cigarettes, Chemical Research in Toxicology, DOI: 10.1021/acs.chemrestox.1c00070.
• Type: Journal Articles Status: Published Year Published: 2021 Citation: James D. Cope, Karizza A. Abellar, Kelvin H. Bates, Xuan Fu, Tran B. Nguyen*, Aqueous Photochemistry of 2-Methyltetrol and Erythritol as Sources of Formic Acid and Acetic Acid in the Atmosphere, ACS Earth and Space Chemistry, Mario Molina Special Issue, 2021, 5, 6, 12651277
• Type: Journal Articles Status: Published Year Published: 2021 Citation: Kelvin H. Bates, James D. Cope, Tran B. Nguyen*, Gas-phase oxidation rates and products of 1,2-dihydroxy isoprene, Environmental Science & Technology, 55, 20, 1429414304
• Type: Journal Articles Status: Published Year Published: 2021 Citation: Karizza A. Abellar, James D. Cope, Tran B. Nguyen*, Second-order kinetic rate coefficients for the aqueous-phase hydroxyl radical (OH) oxidation of isoprene-derived secondary organic aerosol compounds at 298 K, Environmental Science & Technology, 2021
• Type: Journal Articles Status: Published Year Published: 2021 Citation: Kelvin H. Bates, Guy J.P. Burke, James D. Cope, Tran B. Nguyen*, Secondary organic aerosol and organic nitrogen yields from the nitrate radical (NO3) oxidation of alpha-pinene from various RO2 fates, Atmospheric Chemistry and Physics, 22 (2), 1467-1482
• Type: Theses/Dissertations Status: Published Year Published: 2021 Citation: Aerosolization and Thermal Degradation Chemistry of Electronic Cigarettes

Progress 10/01/19 to 09/30/20

Outputs
Target Audience:The target audience includes other scientists, regulatory agencies, and the general public. Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided?In the reporting period, this project has provided opportunities for training three undergraduate students in Environmental Toxicology and Chemistry, one PhD student in Agricultural and Environmental Chemistry, and two postdoctoral scholars. How have the results been disseminated to communities of interest?The results have been disseminated in the forms of peer-reviewed journal publications. Due to COVID-19, the PI's group is not participating in conference proceedings as a form of dissemination. What do you plan to do during the next reporting period to accomplish the goals?The Nguyen group plans to perform photochemical chamber experiments to (1) assess the kinetic lifetime of organic PM particles in the atmosphere under relevant aging conditions, (2) finalize the papers aqueous, gas, and multi-phase oxidation, and (3) further the work on toxicity and chemistry of particles from e-cigarette use.

Impacts
What was accomplished under these goals? During this reporting period, we have conducted a series of experiments on the chemistry and toxicological effects of electronic cigarette "smoke", outdoor particulate matter (PM) in California's Imperial County, PM and volaltile compounds above forests, and PM from smoldering woodsmoke. Toxicity testing included in-vitro cell assays as well as in-vivo animal exposures to air pollution mixtures and electronic cigarettes. In these works, we performed a number of untargeted chemical ionization mass spectrometry (CIMS), high-resolution mass spectrometery (HRMS) analyses to characterize the molecular composition of gases and aerosols, which enabled us to discuss links between the aerosol components and their toxicity effects. These works have been published in four peer-reviewed articles in prominent and high-impact journals. These accomplishments satisfy goals 2 and 3. We also performed number of aqueous phase, gas phase, and multi-phase experiments using photochemical chambers in order to elucidate the chemistry and kinetics of aerosol formation in areas of biogenic and agricultural influence. Much of this work will be included in a national database that Dr. Nguyen has developed (icarus.ucdavis.edu). This accomplishment achieves Goal 1.

Publications

• Type: Journal Articles Status: Published Year Published: 2020 Citation: Li, Y., A.E. Burns, G.J.P. Burke, M.E. Poindexter, A.K. Madl,K.E. Pinkerton, and T.B. Nguyen. Application of high-resolution mass spectrometry and a theoretical model to the quantification of multifunctional carbonyls and organic acids in e-cigarette aerosol. Environmental Science and Technology, 54(9): 56405650.
• Type: Journal Articles Status: Published Year Published: 2020 Citation: Chan, L.K., K.Q. Nguyen, N. Karim, Y. Yang, R.H. Rice, G. He, M.S. Denison, and T.B. Nguyen. Relationship between the molecular composition, visible light absorption, and health-related properties of smoldering woodsmoke aerosols. Atmospheric Chemistry and Physics, 20: 539-559.
• Type: Journal Articles Status: Published Year Published: 2020 Citation: Link, M., T.B. Nguyen, K.H. Bates, J.-F. M�ller, D.K. Farmer. Can isoprene oxidation explain high concentrations of atmospheric formic and acetic acid over forests? ACS Earth and Space Chemistry, (4) 730-740.
• Type: Journal Articles Status: Published Year Published: 2020 Citation: D'Evelyn SM, C.F.A. Vogel, K.J. Bein, B. Lara, E.L. Laing, R.A. Abarca, Q. Zhang, T.B. Nguyen, and K.E. Pinkerton. Differential inflammatory potential of particulate matter (PM) size fractions from Imperial Valley, CA. Atmospheric Environment, 244: 117992.

Progress 10/01/18 to 09/30/19

Outputs
Target Audience:The target audience includes other scientists, regulatory agencies, and the general public. Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided?The project has provided opportunities for training two undergraduate students in Environmental Toxicology and two PhD students in Agricultural and Environmental Chemistry and Atmospheric Science. The project has provided the opportunity for the PI and two students to attend national scientific conferences in order to present their findings and to network with colleagues. How have the results been disseminated to communities of interest?The results have been disseminated in the forms of peer-reviewed journal publications and oral platform presentations. What do you plan to do during the next reporting period to accomplish the goals?The Nguyen group plans to perform photochemical chamber experiments to (1) assess the kinetic lifetime of organic PM particles in the atmosphere under relevant aging conditions, (2) finalize the paper on oxidation of alpha-pinene, and (3) further the work on toxicity and chemistry of particles from e-cigarette use.

Impacts
What was accomplished under these goals? During this reporting period, we have conducted a series of experiments on the toxicological effects of particulate matter (PM) from smoldering woodsmoke. The woodsmoke PM were subjected to in-vitro testing for toxicity, AhR activity, and estrogenic activity as well as light absorption characterization. We also performed a number of high-resolution mass spectrometery analyses and found statistical correlations between the PM components and their toxicity effects. This work has recently been accepted for publication in Atmospheric Chemistry and Physics. This accomplishment achieves Goals 2 and 3. Also, we performed number of experiments in our photochemical chamber on the oxidation of alpha-pinene (a major volatile emission in the atmosphere) with the nitrate radical and characterized its pathways for forming organic PM. We were able to distinguish the different radical branching fates of this reaction. This work has been published as two platform presentations at the American Association for Aerosol Research and the American Chemical Society. This accomplishment achieves Goal 1.

Publications

• Type: Journal Articles Status: Accepted Year Published: 2019 Citation: Chan, LK, Nguyen, K.Q., Karim, N., Yang, Y., Rice, R.H., He, G., Denison, M.S., Nguyen, T.B., Relationship between the molecular composition, visible light absorption, and health-related properties of smoldering woodsmoke aerosols, Atmos. Chem. Phys., [Accepted], 2019
• Type: Journal Articles Status: Published Year Published: 2019 Citation: Schwantes RH, Charan SM, Bates KH, Huang Y, Nguyen TB, Mai H, Kong W, Flagan RC, Seinfeld JH. Low-volatility compounds contribute significantly to isoprene secondary organic aerosol (SOA) under high-NO x conditions. Atmos Chem Phys. 2019;19(11):7255-78.
• Type: Journal Articles Status: Published Year Published: 2019 Citation: Schuster, D.C., M.S. Mayernik, C. Hou, G. Stossmeister, R.R. Downs, D. Kinkade, T.B. Nguyen, M. Ramamurthy, and F. Zhang, 2019: Challenges and Future Directions for Data Management in the Geosciences. Bull. Amer. Meteor. Soc., 100, 909912, https://doi.org/10.1175/BAMS-D-18-0319.1
• Type: Conference Papers and Presentations Status: Published Year Published: 2019 Citation: Nguyen T.B., Burke G.J.P., Li, Y., Mechanism of the nitrate oxidation of ?-pinene under simulated ambient conditions, American Chemical Society, March 2019 (Invited Talk)
• Type: Conference Papers and Presentations Status: Published Year Published: 2019 Citation: Burke G.J.P., Li, Y. and Nguyen T.B., MOrganic Nitrate and Secondary Organic Aerosol Formation from the Reaction of Alpha-Pinene and Nitrate Radical under Simulated Ambient Conditions, American Association for Aerosol Research, October 2019

Progress 10/01/17 to 09/30/18

Outputs
Target Audience:The target audience includes other scientists, regulatory agencies, and the general public. Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided?The project has provided opportunities for training three undergraduate students in Environmental Toxicology, one master's students in Forensic Science, two PhD students in Agricultural and Environmental Chemistry and Atmospheric Science, one postdoctoral scholar, and one staff researcher. The project has provided the opportunity for the PI and two students to attend national scientific conferences in order to present their findings and to network with colleagues. How have the results been disseminated to communities of interest?The results have been disseminated in the forms of peer-reviewed journal publications, oral platform presentation, poster presentations, and as classroom lectures when the PI incorporated her research in atmospheric and analytical chemistry into her class curricula for ETX 111 (Introduction to Mass Spectrometry) and ETX 102a (Environmental Fates of Toxicants). What do you plan to do during the next reporting period to accomplish the goals?The Nguyen group plans to perform photochemical chamber experiments to (1) assess the kinetic lifetime of organic PM particles in the atmosphere under relevant aging conditions, (2) investigate the yield of PM during the nighttime oxidation of alpha-pinene, and (3) further characterize the toxicity-linked composition of woodsmoke aerosols and publish the results.

Impacts
What was accomplished under these goals? The PI's group has performed research that has improved our understanding of how organic PM and SVOCs form from biomass burning (smoldering fires) and chemistry involving biogenic hydrocarbons in the presence of urban pollution (namely NOx). These data have been disseminated in the research products described above. Additionally, the PI has developed instruments and equipment for research in the reporting period, as described above.

Publications

• Type: Journal Articles Status: Published Year Published: 2017 Citation: Kurt�n T., K.H. M�ller, T.B. Nguyen, R.H. Schwantes, P.K. Misztal, L. Su, P.O. Wennberg, J.L. Fry, H.G. Kj�rgaard. Alkoxy Radical Bond Scissions Explain the Anomalously Low Secondary Organic Aerosol and Organonitrate Yields from ?-Pinene + NO3. Journal of Physical Chemistry Letters.
• Type: Journal Articles Status: Published Year Published: 2018 Citation: Wennberg, P.O.; K.H. Bates.; J.D. Crounse; L. Dodson; R. McVay; L. Mertens; T.B. Nguyen; E. Praske; R.H. Schwantes ; M. Smarte; J.M. St. Clair; A.P. Teng; X. Zhang; and J.H. Seinfeld. The gas-phase reactions of isoprene and its major oxidation products. Chemical Reviews, 118(1): 3337-3390.
• Type: Journal Articles Status: Accepted Year Published: 2018 Citation: Paulot, F., S. Malyshev, T.B. Nguyen, J.D. Crounse, and E. Shevliakova. Downscaling of nitrogen dry deposition in the GFDL climate model: implications for present and future nitrogen deposition in North America. Atmospheric Chemistry and Physics
• Type: Journal Articles Status: Published Year Published: 2018 Citation: Zare, A., P.S. Romer, T.B. Nguyen, F.N. Keutsch, K. Skog, and R.C. Cohen. A comprehensive organic nitrate chemistry: insights into the lifetime of atmospheric organic nitrate. Atmospheric Chemistry and Physics, 18: 15419-15436
• Type: Conference Papers and Presentations Status: Published Year Published: 2018 Citation: High resolution mass spectrometry analysis of biomass burning organic aerosol composition from different wood fuels and combustion conditions, K Nguyen, H Bayat, M Hengel, T Nguyen, ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY 255
• Type: Conference Papers and Presentations Status: Published Year Published: 2018 Citation: Characterization of thirdhand smoke constituents on aged smoke-exposed fabrics using high resolution mass spectrometry, H Bayat, A Whitlatch, W Jiang, Q Zhang, S Schick, T Nguyen, ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY 255

Progress 10/01/16 to 09/30/17

Outputs
Target Audience:The target audience for this research include members of the public, regulatory agencies (such as Environmental Protection Agency and California Air Resources Board), the National Science Foundation, and atmospheric modelers who use the environmental data as inputs for their models. Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided?As described in the accomplishments section, the project has provided opportunities for the professional development of one Environmental Toxicology undergraduate student, Ms. Helena Bayat (who is pursuing an Honor's thesis under the guidance of Prof. Nguyen) and one Forensics masters student, Ms. Khanh Nguyen. The project allowed for both of these young scientists to disseminate their work at a major national conference, the American Chemical Society conference. How have the results been disseminated to communities of interest?The current results of the project will be disseminated in the form of conference and journal publications as described in the research products section. What do you plan to do during the next reporting period to accomplish the goals?The Nguyen Group will be able to use the scientific infrastructure set up during this review period (atmospheric chamber, instruments, etc.) to further investigate the research themes described in the proposal. In particular, Prof. Nguyen will undertake a study on the photochemical fate of fine particulate matter (PM) that are formed from the interactions of biogenic and anthropogenic emissions. Continuted efforts include: (a) research on biomass burning PM and their toxicological properties, (b) the development of the ICARUS database, and (c) interdisciplinary research with UC Davis colleagues.

Impacts
What was accomplished under these goals? One of the stated "Products" of the research is "New instrument and instrumental techniques." Prof. Nguyen spent a major part of her startup timeline developing her group's scientific infrastructure. Within the review period, Prof. Nguyen has built a custom 8 m3 atmospheric chamber with 20 m3 insulated enclosure, custom mass spectrometry instrument, custom mass spectrometry ion source, custom combustion chamber, and have set up several other laboratory sensors in order to carry out the research described in the AES proposal. Prof. Nguyen has successfully fabricated the chemical ionization mass spectrometry (CIMS) instrument that was described in the original AES proposal, which is a unique and significant addition to campus analytical capabilities. While the CIMS is highly valuable for atmospheric chemistry research in the Nguyen group (and the larger Air Quality Research group), it has also proven to be useful for interdisciplinary collaborative science including wine vapor analysis (Boulton Group) and e-cigarette vapor analysis (Pinkerton Group). Prof. Nguyen's group members are in the process of collecting data for each stated goal in the AES proposal, including (1) formation pathways for particulate matter (PM) from agricultural and combustion emissions, (2) improving the characterization of PM components, and (3) characterizing the toxicological effects of organic PM. Students in the group (Khanh Nguyen and Helena Bayat), who performed the research, are presenting their findings at the March 2018 American Chemical Society meeting in New Orleans. Their conference papers are not listed on this report, however, because the presentations will not occur in the review period, even though the students' efforts occurred during the review period. In particular, Ms. Bayat has successfully developed analytical methods to analyze tobacco particulate matter on complex surfaces (such as drywall) and Ms. Nguyen has performed both analytical chemistry and toxicological assays on biomass burning PM. Ms. Nguyen performed the controlled burns herself, similarly to agricultural prescribed burns, using the group's combustion chamber. Lastly, although this was not described in the original proposal, Prof. Nguyen is spearheading a national effort to establish a database for atmospheric and aerosol science in the United States. The effort was initiated by the California Air Resources Board, who contracted Prof. Nguyen to do a feasibility study in 2016, and eventually funded by the National Science Foundation in 2017 after a collaborative proposal was submitted. While this major collaborative effort is not yet fully finished, its establishment should still be considered a significant accomplishment due to the large scale and the fact that it will be the first of its kind in the United States after nearly a decade of scientific interest and a sister database in Europe.

Publications

• Type: Conference Papers and Presentations Status: Published Year Published: 2016 Citation: P Misztal, L Su, J-H Park, R Holzinger, T Nguyen, A Teng, J St Clair, P Wennberg, J Crounse, R Seco, T Karl, L Kaser, A Hansel, E Canaval, E Partoll, B Mentler, B Lepesant, J-P Schnitzler, F Keutsch, J Mak, A Guenther, and A H Goldstein, "Flux observations of isoprene oxidation products above a South East US forest point to chemical conversions on leaf canopy surface", American Geophysical Union, 2016
• Type: Conference Papers and Presentations Status: Published Year Published: 2016 Citation: Kelvin H. Bates, Renee C. McVay, Alex P. Teng, John D. Crounse, Tran B. Nguyen, Eric Praske, Rebecca H. Schwantes, Jason M. St Clair, Hannah M. Allen, John H. Seinfeld, and Paul O. Wennberg, "Incorporating recent advances in isoprene photooxidation into GEOS-Chem: Effects on oxidant, NOx, and VOC budgets," American Geophysical Union, 2016
• Type: Conference Papers and Presentations Status: Published Year Published: 2017 Citation: TRAN NGUYEN, William P. L. Carter, David R. Cocker III, Neil Donahue, Lea Hildebrandt Ruiz, Jose-Luis Jimenez, Ajith Kaduwela, Nga Lee Ng, Sergey Nizkorodov, John Orlando, Spyros Pandis, Allen Robinson, John Seinfeld, Geoffrey Tyndall, Paul Ziemann,"ICARUS: An Online, Open-access, and Searchable Database for Atmospheric Chamber Research in the United States", American Association for Aerosol Research, 2017
• Type: Journal Articles Status: Under Review Year Published: 2018 Citation: Wennberg, P.O.; K.H. Bates.; J.D. Crounse; L. Dodson; R. McVay; L. Mertens; T.B. Nguyen; E. Praske; R.H. Schwantes ; M. Smarte; J.M. St. Clair; A.P. Teng; X. Zhang; and J.H. Seinfeld. The gas-phase reactions of isoprene and its major oxidation products. Chemical Reviews, Under Review after Minor Revisions