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Updated: Jul 12, 2026
13:29
Production and Measurement of Organic Particulate Matter in a Flow Tube Reactor
Published on: December 15, 2018
Characterizing multiphase organic/inorganic/aqueous aerosol droplets
Jariya Buajarern1, Laura Mitchem, Jonathan P Reid
1School of Chemistry, University of Bristol, Bristol, BS8 1TS, U.K.
The Journal of Physical Chemistry. A
|August 28, 2007
Summary
Researchers used optical tweezers to study how volatile organic compounds partition within aerosol droplets. They observed phase segregation and measured organic layer thickness with nanometer accuracy, revealing insights into aerosol behavior.
Area of Science:
- Physical Chemistry
- Aerosol Science
- Spectroscopy
Background:
- Aerosols play a critical role in atmospheric processes and climate.
- Understanding the behavior of multicomponent aerosols is essential for accurate atmospheric modeling.
- Immiscible organic and aqueous phases in aerosols can significantly alter their physical and chemical properties.
Purpose of the Study:
- To investigate the partitioning of immiscible volatile organic components within aqueous aerosol droplets.
- To characterize the phase segregation and equilibrium geometries of mixed organic-aqueous aerosols.
- To determine the thickness of organic layers on aqueous droplets with high precision.
Main Methods:
- Utilized optical tweezers to manipulate single aerosol droplets.
- Employed brightfield microscopy for visual characterization.
- Applied spontaneous and stimulated Raman scattering for chemical analysis.
- Compared nonlinear spectroscopic signatures with Mie scattering predictions for core-shell structures.
Main Results:
- Observed equilibrium geometries of immiscible phases consistent with surface energy predictions.
- Identified the formation of thin organic films or lenses on aqueous droplets at low organic volume fractions.
- Estimated organic layer thickness with nanometer accuracy.
- Monitored the dynamic partitioning of volatile organic components between condensed and vapor phases.
Conclusions:
- The study provides a detailed understanding of phase segregation in mixed organic-aqueous aerosols.
- Optical tweezers and Raman spectroscopy are powerful tools for characterizing aerosol microstructures.
- The findings contribute to more accurate modeling of aerosol behavior and their atmospheric impact.
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