Background
Teaching
Research
Interests
Publications
and Presentations
Other
Interesting Links
Background
I grew up near Chicago, but went to Los Angeles for my liberal
arts education at Occidental
College . There, I had my first exposure to research working
with David West and Eileen Spain. After graduating (1996), I decided
to do something unrelated to science and went to Argentina. I volunteered
in a home for boys in Buenos Aires, learned Spanish, and ate a lot
of beef. Chemistry still called me, however, and so I went to the
University of
Minnesota for graduate school. Working in the lab of Jeffrey
T. Roberts, I learned about ultra high vacuum systems and applications
to atmospheric chemistry. I left Minnesota in 2002 for NASA
Ames Research Center, where I was immersed in the atmospheric
science community. After three fun years, I came to Randolph-Macon
in 2005.
Teaching
Fall 2005: General Chemistry Lab, Physical Chemistry I, and Advanced
Lab I
Spring 2006: General Chemistry Lab, Physical Chemistry II, and Advanced
Lab II
Research Interests
Interfaces are ubiquitous in the atmosphere, from
the tiny surfaces of aerosol particles miles above the ground to
the extensive sea ice and snow pack of high latitudes. Aerosol particles
can serve as miniature chemical reactors, taking up gases and converting
them to different compounds, affecting the concentrations of trace
species in the atmosphere. Furthermore, cloud droplets form on aerosol
seed particles. Both aerosol and cloud particles absorb radiation
and reflect it back to space and/or back to earth, and therefore
play an important role in climate change. In snow and ice covered
regions, organic gases evolve from the snow and appear to affect
ozone and mercury chemistry. Such snow-induced chemistry may also
occur in cities that experience snowfall, leading to concerns for
human health. Our research focuses on laboratory studies that elucidate
chemistry and dynamics at atmospheric interfaces. In particular,
three projects are currently being developed. 1) In order to understand
the composition of acidic sulfate aerosols, we will investigate
the dissolution and speciation (fast reversible reactions) of volatile
organic compounds in sulfate solutions. 2) The feasibility of cross-reactions
in such solutions under atmospheric conditions will be assessed
in an ongoing collaboration with NASA Ames Research Center. 3) We
will explore ice surfaces at atmospherically relevant temperature
and pressure. We will attempt to measure the properties of the ice
surface, such as its ability to solvate, and its effective pH.
Recent Publications
R.R. Michelsen, S.J.R. Staton, and L.T. Iraci. “Uptake and
Dissolution of Gaseous Ethanol in Sulfuric Acid.” submitted
to Journal of Physical Chemistry A, October 2005.
R.R. Michelsen, S.F.M. Ashbourn, and L.T. Iraci. “Dissolution,
Speciation and Reaction of Acetaldehyde in Cold Sulfuric Acid.”
Journal of Geophysical Research D, 109, D23205, doi:10.1029/2004JD005041,
2004.
R.R. Michelsen and J.T. Roberts. "The Pressure-Dependent Kinetics
of Acetone Uptake by Sulfuric Acid: Evidence for a Second-Order
Heterogeneous Reaction." in press, Atmospheric Environment,
2004.
R.R. Michelsen and J.T. Roberts. “Reactive Uptake of 2,5-Hexanedione
by Ultrathin Sulfuric Acid Films,” manuscript in preparation
for Journal of Physical Chemistry.
L.T. Iraci, R.R. Michelsen, S.F.M. Ashbourn, T.A. Rammer, and D.
Golden. “Uptake of Hypobromous Acid (HOBr) by Aqueous Sulfuric
Acid Solutions: Low-Temperature Solubility and Reaction,”
Atmospheric Chemistry and Physics Discussions, 5, 1213-1239,
2005.
B. Riffel, R.R. Michelsen, S.J.R. Staton, and L.T. Iraci. “Acid
catalyzed nitration of methanol: Formation of methyl nitrate via
aerosol chemistry,” manuscript in preparation for Journal
of Atmospheric Chemistry.
Recent Presentations
R.R. Michelsen and L.T. Iraci. “Cross-Reactions of Organic
Trace Compounds in Cold, Acidic Sulfate Particles.” American
Geophysical Union 2005 Fall Meeting, San Francisco, CA, December
2005.
R.R. Michelsen, S.J.R. Staton, and L.T. Iraci. “Ethanol as
a Fuel Component: Effect on Aerosol Composition” Air Pollution
as a Climate Forcing: A Second Workshop, Honolulu, HI, April 2005.
R.R. Michelsen, S.F.M. Ashbourn, S.J.R. Staton, and L.T. Iraci.
“Accommodation of Oxygenated Organic Vapors into Sulfate Particles:
Dissolution, Speciation and Reaction.” 8th Scientific Conference
of the IGAC Project, Christchurch, New Zealand, September 2004.
R.R. Michelsen, S.J.R. Staton, and L.T. Iraci. “How Does
Chemistry Affect Gas Uptake? Oxygenated Organics and Sulfuric Acid.”
American Chemical Society National Meeting, Philadelphia, PA, August
2004.
S.J.R. Staton, R.R. Michelsen and L.T. Iraci. “Ethanol Emissions:
Interactions with Particles.” Posters on the Hill, Council
for Undergraduate Research, Washington, DC, April 2004.
R.R. Michelsen, S.F. Ashbourn and L.T. Iraci. “Dissolution
and Speciation of Oxygenated Organic Compounds in Sulfate Particles:
Acetaldehyde.” American Geophysical Union 2003 Fall Meeting,
San Francisco, CA, December 2003.
Other Interesting Links
Ozone data
from NASA
Snowcrystals
Physical
Chemistry Data (see 36 for character tables):
Another
character table
NIST webbook
NASA
Undergraduate Student Research Program