Title: | Production and Measurement of Organic Particulate Matter in the Harvard Environmental Chamber |
Author(s): | Zhang Y; Gong Z; Sa S; Bateman AP; Liu Y; Li Y; Geiger FM; Martin ST; |
Address: | "School of Engineering and Applied Sciences, Harvard University; Department of Environmental Science and Engineering, Gillings School of Global Public Health, University of North Carolina; yzhang01@live.unc.edu. School of Engineering and Applied Sciences, Harvard University. Department of Chemistry, Northwestern University; geigerf@chem.northwestern.ed. School of Engineering and Applied Sciences, Harvard University; Department of Earth and Planetary Sciences, Harvard University; scot_martin@harvard.ed" |
ISSN/ISBN: | 1940-087X (Electronic) 1940-087X (Linking) |
Abstract: | "The production and the evolution of atmospheric organic particulate matter (PM) are insufficiently understood for accurate simulations of atmospheric chemistry and climate. The complex production mechanisms and reaction pathways make this a challenging research topic. To address these issues, an environmental chamber, providing enough residence time and close-to-ambient concentrations of precursors for secondary organic materials, is needed. The Harvard Environmental Chamber (HEC) was built to serve this need, simulating the production of gas and particle phase species from volatile organic compounds (VOCs). The HEC has a volume of 4.7 m(3) and a mean residence time of 3.4 h under typical operating conditions. It is operated as a completely mixed flow reactor (CMFR), providing the possibility of indefinite steady-state operation across days for sample collection and data analysis. The operation procedures are described in detail in this article. Several types of instrumentation are used to characterize the produced gas and particles. A High-Resolution Time-of-Fight Aerosol Mass Spectrometer (HR-ToF-AMS) is used to characterize particles. A Proton-Transfer-Reaction Mass Spectrometer (PTR-MS) is used for gaseous analysis. Example results are presented to show the use of the environmental chamber in a wide variety of applications related to the physicochemical properties and reaction mechanisms of organic atmospheric particulate matter" |
Keywords: | Aerosols/analysis/chemistry Air Pollutants/analysis/chemistry Environmental Monitoring/instrumentation/*methods Mass Spectrometry/methods Particulate Matter/*analysis/*chemistry Tandem Mass Spectrometry/*methods Volatile Organic Compounds/analysis/chemist; |
Notes: | "MedlineZhang, Yue Gong, Zhaoheng Sa, Suzane de Bateman, Adam P Liu, Yingjun Li, Yongjie Geiger, Franz M Martin, Scot T eng Research Support, Non-U.S. Gov't Research Support, U.S. Gov't, Non-P.H.S. Video-Audio Media 2018/12/07 J Vis Exp. 2018 Nov 18; (141). doi: 10.3791/55685" |