Equilibrium vapor pressure of water over multiple aerosol particles /
One of the fundamental problems in atmospheric aerosol
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| Format: | Thesis Book |
| Language: | English |
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[Place of publication not identified] :
[publisher not identified] ;
1996.
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| Online Access: | http://proxy.library.tamu.edu/login?url=http://proquest.umi.com/pqdweb?did=739669291&sid=1&Fmt=2&clientId=2945&RQT=309&VName=PQD |
| Summary: | One of the fundamental problems in atmospheric aerosol studies is determination of equilibrium vapor pressures over insoluble aerosol particles. In this study we investigate the influence of both solution and geometry on equilibrium vapor pressure over complex aerosol particles. The aerosol substrates in our investigation are single and multiple structureless adhering macroscopic (i.e. radius R> 50nm), relatively hydrophobic spheres. First, the equilibrium vapor pressures of water are calculated for two different geometric configurations: a liquid cap formed on a single substrate sphere and a liquid pendular ring formed about the contact point of a pair of adhering, identical spheres. For each configuration, pure water and sulfuric acid solution are used separately as the interface liquid. Our calculations utilize the tabulated data of activity of water over the sulfuric acid solution and the solution density. Second, we focus on the same problems as mentioned above by using the Surface Evolver program, which is an interactive program for the study of surfaces minimizing some energy subject to constraints, e.g. surface tension and other energies. Third, since numerous studies have been focused on soot aggregates, we use the Evolver program to study the equilibrium water vapor pressure over those configurations formed by three or four insoluble spherical particles.(the simplest and basis of chain aggregate formation), and to investigate whether configuration geometry can affect aerosol particles to be served as initial nuclei for cloud condensation whose relative humidity < 102%. The calculations show that the equilibrium water vapor pressure over a configuration containing sulfuric acid solution is always less than the equilibrium vapor pressure over the same configuration with pure water surface. Also our calculations indicate that geometrical configurations play an important role on equilibrium vapor pressure over aggregate aerosol particles. Formations formed on four substrate spheres are more favorable for condensation than the pendular ring formed by two spheres and other formations by three spheres, and in the cap configuration, condensational growth is usually limited for any subsaturation relative humidity. |
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| Item Description: | Vita. "Major Subject: Physics". |
| Physical Description: | xiii, 175 leaves : illustrations ; 28 cm. Issued also on microfiche from University Microfilms Inc. |
| Bibliography: | Includes bibliographical references: pages 89-95. |