Engineering topics
Publications and source records attributed to Hall, Derek.
This computational tool provides the standard Gibbs energy of formation for aqueous species, the dielectric constant and ionization constant of water, over a wide range of temperatures, pressures, and densities both above and below the critical point of water.
This work provides an advanced standard molar Gibbs energy of formation model, informed by molecular statistical thermodynamics (MST), and validated by mineral solubility and ion association reactions. This new model aligns with experimental data within uncertainties and highlights the role of specific MST interactions around the critical point. This work will provide a reliable tool for the optimization of industrial processes operating at the edges of the supercritical domain.
We exhibit the operational energy storage density (W-h L-1) of various redox flow battery technologies based on consideration from experimental parameters and results from literature as key inputs.
In this presentation, the MBES shows the ability to detect the change in exposed environment even with cold-spray coatings. Corrosion rates from the cold-spray coating were comparable to a 316 stainless steel sample. Defects in the coating did not impact sensor performance in terms of corrosion rate or water content detection. Energy dispersive X-ray spectroscopy was used to document ion migration into the membrane.
We present a thermodynamic model to predict the solubility of various minerals found in the oil field. The contribution of major model components is discussed.
Chapter 5 of Solid-Liquid Separation Technologies: Applications for Produced Water. In this chapter we employed a molecular statistical thermodynamic-based model to predict the behavior of barite-containing species at high temperatures and high pressures.
239th Electrochemical Society Meeting with the 18th International Meeting on Chemical Sensors, May 30-June 3, 2021 Poster presentation
Membrane-based electrochemical sensors (MBES) provide an attractive option for real-time continuous humidity and corrosion rate measurements inside of natural gas pipelines. The MBES, can use electrochemical techniques such as linear polarization resistance and electrochemical impedance spectroscopy even when a conductive aqueous phase is intermittent or unavailable. We now present field-test performance data of our MBES operated inside a multiphase water and natural gas flow facility. The MBES measured internal corrosion and conductivity at the top, bottom, and side of the pipe spool. Tests were carried out with flow rates of 4.6, 9.1, and 18.3 m/s, temperatures of 21, 29, and 35 °C, and a pressure of 1000 psia. All sensors followed similar trends in open circuit potential, corrosion rate, and conductivity over time. Neither flow rate, temperature, nor build-up of metal-based solids on the sensor surfaces impacted the quality of the electrochemical measurements. The field-test results confirm that the membrane-based electrochemical sensors are suitable for monitoring internal corrosion of operational natural-gas pipelines.
Summary of western burrowing owl satellite-tracking study on the NNSS for the Fall issue of the Nevada Chapter of The Wildlife Society Newsletter.
Details results from radiotracking a newly discovered reproducing population of desert bighorn sheep on the Nevada National Security Site including, movement patterns, disease prevalence, population estimates, and radiological analyses.