Earth
and Space Sciences Faculty |
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Evan
Abramson |
Research Group:
Mineral
Physics Group
Education:
Ph.D. in Physical Chemistry, MIT,
1985
Personal Research:
Little information is available
concerning the thermodynamic properties of fluids above pressures of ~1 GPa
(10 kbar) and practically no information on their transport properties (i.e.,
chemical diffusivity, thermal diffusivity, shear viscosity). For the most part,
this situation is a result of the lack of techniques suitable to the exigencies
of the high-pressure, diamond-anvil cell and also to the necessity, for all
but a very few substances, of working at elevated temperatures.
In the last several years, our group has pioneered the application of transient optical gratings to the measurement both of speed of sound (a thermodynamic function) and thermal diffusivity within the diamond-anvil cell. These methods are being constantly improved and are being applied to a broad sampling of simple fluids, from hydrogen-bonded water and ammonia, to the noble gases, up to the pressures, associated densities and temperatures readily accessible in the diamond-anvil cell. Several new possibilities for the measurement both of viscosity and mass diffusion are also being explored. Our goal is to acquire data which can form the basis for an understanding of the basic properties of fluids under conditions of high pressure and density.
In addition to fluids, we have used some of the same techniques to study simple solids such as (crystalline) argon and oxygen, metals such as iron and tantalum, and silicate minerals.
Here's a figure which shows a few of the interesting phenomena which occur at high pressures, both from a geophysical and general perspective.
Here's a schematic of a diamond-anvil cell and a photograph taken through the backs of the diamonds. In the photo the pink, vaguely rectangular object is a single crystal of oxygen held at room temperature and 57 kbar, floating in supercritical fluid oxygen. The adjacent, colorless crystal is a piece of ruby, our pressure gauge. A platinum sphere, used to measure the viscosity of the fluid, is visible as a round, dark object. Several of the diamond facets can be seen around the perimeter.
Selected Publications:
“Speed of sound and equation
of state for fluid oxygen to 10 GPa”, E.H. Abramson, L.J. Slutsky, M.D.
Harrell, J.M Brown, Journal of Chemical Physics, 110, 21, 10493 (1999).
“Thermal diffusivity of fluid oxygen to 12 GPa and 300 degrees C”, E.H. Abramson, L.J. Slutsky, J.M. Brown, Journal of Chemical Physics, 111, 20, 9357 (1999).
“Applications of Impulsive Stimulated Scattering in the Earth and Planetary Sciences”, E.H. Abramson, J.M. Brown, L.J. Slutsky, Annu. Rev. Phys. Chem., 50, 279 (1999).
"Surface Acoustic Waves in the Diamond-Anvil Cell: An Application of Impulsive Stimulated Light Scattering", J.C. Crowhurst, E.H. Abramson, L.J. Slutsky, J.M. Brown, J.M Zaug and M.D. Harrell, Physical Review B, 64, 100103(R)1-4, (2001).
"The Thermal Diffusivity of Water at High Pressures and Temperatures", E.H. Abramson, J.M. Brown and L.J. Slutsky, Journal of Chemical Physics, 115, 10461-3 (2001).
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Earth and Space Sciences (Geology, Geophysics, Geological Sciences) University of Washington Johnson Hall 070 • Box 351310 4000 15th Avenue NE • Seattle, WA 98195-1310 Phone 206-543-1190 • Fax 206-543-0489 • Site Info: webmaster@ess.washington.edu • ESS Advising: advising@ess.washington.edu |
