Abstract
Organic particulate matter (PM) is increasingly recognized as important to the Earth’s climate system as well as public health in urban regions, and the production of synthetic PM for laboratory studies have become a widespread necessity. Herein, experimental protocols demonstrate approaches to produce aerosolized organic PM by a-pinene ozonolysis in a flow tube reactor. Methods are described for measuring the size distributions and morphology of the aerosol particles. The video demonstrates basic operations of the flow tube reactor and related instrumentation. The first part of the video shows the procedure for preparing gas-phase reactants, ozonolysis, and production of organic PM. The second part of the video shows the procedures for determining the properties of the produced particle population. The particle numberdiameter distributions show different stages of particle growth, namely condensation, coagulation, or a combination of both, depending on reaction conditions. The particle morphology is characterized by an aerosol particle mass analyzer (APM) and a scanning electron microscope (SEM). The results confirm the existence of non-spherical particles that have grown from coagulation for specific reaction conditions. The experimental results also indicate that the flow tube reactor can be used to study the physical and chemical properties of organic PM for relatively high concentrations and short time frames.
Original language | English (US) |
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Article number | e55684 |
Journal | Journal of Visualized Experiments |
Volume | 2018 |
Issue number | 142 |
DOIs | |
State | Published - Dec 2018 |
Funding
This material is based upon work supported by the National Science Foundation Environmental Chemical Sciences Program in the Division of Chemistry under Grant No. 1111418, the Atmospheric-GeoSciences Division of the U.S. National Science Foundation (NSF) under grant number 1524731, as well as Harvard Faculty Publication Award. We acknowledge Mona Shrestha, Adam Bateman, Pengfei Liu, and Mikinori Kuwata for useful discussions and assistance with the experiments.
Keywords
- Atmospheric Chemistry
- Environmental Sciences
- Flow Tube Reactor
- Issue 142
- Morphology
- Organic Aerosol
- Particulate Matter (PM)
- Secondary Organic Material (SOM)
- Size Distributions
ASJC Scopus subject areas
- General Neuroscience
- General Chemical Engineering
- General Biochemistry, Genetics and Molecular Biology
- General Immunology and Microbiology