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Physical Sciences and Mathematics Commons

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SelectedWorks

Earth Sciences

2003

Articles 1 - 2 of 2

Full-Text Articles in Physical Sciences and Mathematics

Dissolution Of Entrapped Dnapls In Variable Aperture Fractures: Experimental Data And Empirical Model, Sarah E. Dickson, Neil R. Thomson Jan 2003

Dissolution Of Entrapped Dnapls In Variable Aperture Fractures: Experimental Data And Empirical Model, Sarah E. Dickson, Neil R. Thomson

Sarah E Dickson

An appreciation of the dissolution from entrapped nonaqueous phase liquids (NAPLs) in fractures is essential as we attempt to understand and predict the fate of NAPLs present in fractured rock systems. Eight long-term dissolution experiments using 1,1,1-trichloroethane and trichloroethylene were conducted in two laboratory-scale dolomitic limestone variable aperture fractures under various conditions. Between 560 and 2600 fracture volumes of water were passed through the fractures resulting in the removal of 10−60% of the initial mass trapped. The effluent concentration profiles revealed three distinct and characteristic stages of dissolution:  an initial pseudosteady stage, a transient stage, and a tailing stage. On …


Potential Impact Of Subsonic And Supersonic Aircraft Exhaust On Water Vapor In The Lower Stratosphere Assessed Via A Trajectory Model, Gary A. Morris, Joan A. Rosenfield, Mark R. Schoeberl, Charles A. Jackman Jan 2003

Potential Impact Of Subsonic And Supersonic Aircraft Exhaust On Water Vapor In The Lower Stratosphere Assessed Via A Trajectory Model, Gary A. Morris, Joan A. Rosenfield, Mark R. Schoeberl, Charles A. Jackman

Gary A. Morris

We employ a trajectory model to assess the impact on the stratosphere of water vapor present in the exhaust of subsonic and a proposed fleet of supersonic aircraft. Air parcels into which water vapor from aircraft exhaust has been injected are run through a 6-year simulation in the trajectory model using meteorological data from the UKMO analyses with emissions dictated by the standard 2015 emissions scenario. For the subsonic aircraft, our results suggest maximum enhancements of ~150 ppbv just above the Northern Hemisphere tropopause and of much less than 50 ppbv in most other regions. Inserting the perturbed water vapor …