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Articles 1 - 5 of 5
Full-Text Articles in Physical Sciences and Mathematics
Spectral Induced Polarization (Sip) Response Of Biodegraded Oil In Porous Media, Gamal Z. Abdel Aal, Estella A. Atekwana
Spectral Induced Polarization (Sip) Response Of Biodegraded Oil In Porous Media, Gamal Z. Abdel Aal, Estella A. Atekwana
Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works
Laboratory experiments were conducted to investigate the effect of different oil saturation (0.2- 0.8), wetting conditions (water-wet and oil-wet), and the addition of asphaltene on the spectral induced polarization (SIP) response of biodegraded and fresh crude oil in sand columns. In the water-wet case, no significant differences were observed for both the fresh and biodegraded oil and both displayed an increase in the magnitude of the phase (φ) and decrease in the magnitudes of the real (σ′) and imaginary (σ″) conductivity components with increasing oil saturation. In this instance the SIP response is most likely controlled by the conduction and …
Geophysics At The Interface: Response Of Geophysical Properties To Solid-Fluid, Fluid-Fluid, And Solid-Solid Interfaces, Rosemary Knight, Laura J. Pyrak-Nolte, Lee D. Slater, Estella A. Atekwana, Anthony L. Endres, Jil T. Geller, David P. Lesmes, Seiji Nakagawa, Andre Revil, Mukul M. Sharma, Christian Straley
Geophysics At The Interface: Response Of Geophysical Properties To Solid-Fluid, Fluid-Fluid, And Solid-Solid Interfaces, Rosemary Knight, Laura J. Pyrak-Nolte, Lee D. Slater, Estella A. Atekwana, Anthony L. Endres, Jil T. Geller, David P. Lesmes, Seiji Nakagawa, Andre Revil, Mukul M. Sharma, Christian Straley
Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works
Laboratory studies reveal the sensitivity of measured geophysical properties to solid-fluid, fluid-fluid, and solid-solid interfaces in granular and fractured materials. In granular materials, electrical properties and nuclear magnetic resonance relaxation times exhibit a strong dependence on the size and properties of the solid-fluid interface. The electrical and seismic properties of granular materials and the seismic properties of fractured materials reveal a dependence on the size or geometry of fluid-fluid interfaces. Seismic properties of granular and fractured materials are affected by the effective stress and cementing material at solid-solid interfaces. There have been some recent studies demonstrating the use of field-scale …
Sensitivity Of Geoelectrical Measurements To The Presence Of Bacteria In Porous Media, Gamal Z. Abdel Aal, Estella A. Atekwana, Silvia Rossbach, D. Dale Werkema
Sensitivity Of Geoelectrical Measurements To The Presence Of Bacteria In Porous Media, Gamal Z. Abdel Aal, Estella A. Atekwana, Silvia Rossbach, D. Dale Werkema
Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works
We investigated the sensitivity of low-frequency electrical measurements (0.1-1000 Hz) to (1) microbial cell density, (2) live and dead cells, and (3) microbial attachment onto mineral surfaces of clean quartz sands and iron oxide-coated sands. Three strains of Pseudomonas aeruginosa PAO1 (wild type and rhlA and pilA mutant) with different motility and attachment properties were used. Varying concentrations of both live and dead cells of P. aeruginosa wild type in sand columns showed no effect on the real conductivity component (σ′). However, the imaginary conductivity component (σ″) increased linearly with increasing concentrations of live cells in sand columns, whereas minimal …
Effect Of Bacterial Adsorption On Low Frequency Electrical Properties Of Clean Quartz Sands And Iron-Oxide Coated Sands, Gamal Z. Abdel Aal, Estella A. Atekwana, Sylvia Radzikowski, Silvia Rossbach
Effect Of Bacterial Adsorption On Low Frequency Electrical Properties Of Clean Quartz Sands And Iron-Oxide Coated Sands, Gamal Z. Abdel Aal, Estella A. Atekwana, Sylvia Radzikowski, Silvia Rossbach
Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works
Low frequency electrical measurements (0.1-1000 Hz) were conducted to investigate the adsorption effect of Pseudomonas aeruginosa cells onto clean quartz sands and iron-oxide coated sands. The clean quartz sands showed a gradual increase in the microbial adsorption to mineral grains, concurrent with an increase of 13% in the imaginary conductivity component (σ″). However, iron-oxide coated sands (20-100% by weight) showed a rapid increase in microbial adsorption with σ″ reaching a maximum of 37% for the 80-100% iron coated sands. No significant changes were observed in the real conductivity component (σ′) due to microbial adsorption. A power law dependency was observed …
Effects Of Microbial Processes On Electrolytic And Interfacial Electrical Properties Of Unconsolidated Sediments, Gamal Z. Abdal Aal, Estella A. Atekwana, Lee D. Slater, Eliot A. Atekwana
Effects Of Microbial Processes On Electrolytic And Interfacial Electrical Properties Of Unconsolidated Sediments, Gamal Z. Abdal Aal, Estella A. Atekwana, Lee D. Slater, Eliot A. Atekwana
Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works
The effect of microbial processes on electrical properties of unconsolidated sediments was investigated in a laboratory experiment consisting of biotic and abiotic sand columns. The biotic column (nutrient, diesel and bacteria) showed (a) temporal increase in the real, imaginary, and surface conductivity, and (b) temporal decrease in the formation factor. The abiotic columns (nutrient; and nutrient and diesel) showed no significant changes. Increase in microbial population numbers, decrease in organic carbon source, nitrate, and sulfate and increase in dissolved inorganic carbon and fluid conductivity were indicative of microbial activity in the biotic column. We also measure relative increase in the …