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Title: Evolution of Heterogeneous Mixed Siliciclastic/Carbonate Aquifers Containing Metastable Sediments.
Creator: Franco, Daniel, Coulibaly, Kapo, Kunberger, Tanya, Kinzli, Kristoph-Dietrich, Arbelaez, Sebastian, Missimer, Thomas M.
Abstract/Description: Mixed carbonate and siliciclastic marine sediments commonly become freshwater aquifers in eastern coastal regions of the United States and many other global locations. As these deposits age, the carbonate fraction of the sediment is commonly removed by dissolution and the aquifer can become a solely siliciclastic system or contain zones or beds of pure quartz sand. During aquifer evolution, the sediment grain size characteristics, hydraulic conductivity, and porosity change. An investigation...
Show moreMixed carbonate and siliciclastic marine sediments commonly become freshwater aquifers in eastern coastal regions of the United States and many other global locations. As these deposits age, the carbonate fraction of the sediment is commonly removed by dissolution and the aquifer can become a solely siliciclastic system or contain zones or beds of pure quartz sand. During aquifer evolution, the sediment grain size characteristics, hydraulic conductivity, and porosity change. An investigation of these changes using mixed carbonate/siliciclastic sediment samples collected from a modern barrier island beach in southern Florida showed that the average mean grain diameter decreased with removal of the carbonate fraction, but the average hydraulic conductivity and porosity increased slightly, but not to statistical significance. This counterintuitive result occurs because of the change in the pore types from a combined shelter and intergranular pore system producing a dual porosity system in the mixed sediments to a single intergranular pore system in the siliciclastic sediment fraction. Within the mixed carbonate/siliciclastic sediment, in the pure carbonate fraction, large shell fractions form grain‐supported large pores, which become filled with sand‐sized quartz as the shell fragments decrease in size or as the sediment becomes compacted. The hydraulic conductivity increases because the shell fragments that were oriented perpendicular to flow caused an increase in the length of the flow path, or a larger scale tortuosity, compared with the flow through pure quartz sand.
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Date Issued: 2017-05-10
Identifier: 10.1111/gwat.12529, fgcu_ir_001005, http://doi.wiley.com/10.1111/gwat.12529
Format: Citation

Title: Seismic Vulnerability Evaluation of Architectural Glassin Curtain Walls.
Creator: Behr, Richard, Memari, Ali M., Shirazi, Ali, Kremer, Paul A.
Abstract/Description: A method for seismic vulnerability evaluation of architectural glass components within aluminum curtain wall systems is proposed. The methodology involves developing a relationship between the applied drift and the critical stresses generated in the glass and comparison with glass crack initiation stress obtained from test data. On the basis of this method, the existing curtain wall glass components or windows can be inspected, and based on the conditions of the curtain wall and the code...
Show moreA method for seismic vulnerability evaluation of architectural glass components within aluminum curtain wall systems is proposed. The methodology involves developing a relationship between the applied drift and the critical stresses generated in the glass and comparison with glass crack initiation stress obtained from test data. On the basis of this method, the existing curtain wall glass components or windows can be inspected, and based on the conditions of the curtain wall and the code specified maximum allowable drift, a score can be defined, which will represent cracking vulnerability of the glass panel at a given drift magnitude. The results of the vulnerability evaluation procedure can help improve decision making regarding prioritization of possible curtain wall seismic retrofit options.
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Date Issued: 2014-08-25
Identifier: fgcu_ir_000333
Format: Citation

Title: Long-Term Managed Aquifer Recharge in a Saline-Water Aquifer as a Critical Component of an Integrated Water Scheme in Southwestern Florida, USA.
Creator: Missimer, Thomas, Guo, Weixing, Woolschlager, John, Maliva, Robert
Abstract/Description: Managed Aquifer Recharge (MAR) systems can be used within the context of integrated water management to create solutions to multiple objectives. Southwestern Florida is faced with severe environmental problems associated with the wet season discharge of excessive quantities of surface water containing high concentrations of nutrients into the Caloosahatchee River Estuary and a future water supply shortage. A 150,000 m(3)/day MAR system is proposed as an economic solution to solve part of the...
Show moreManaged Aquifer Recharge (MAR) systems can be used within the context of integrated water management to create solutions to multiple objectives. Southwestern Florida is faced with severe environmental problems associated with the wet season discharge of excessive quantities of surface water containing high concentrations of nutrients into the Caloosahatchee River Estuary and a future water supply shortage. A 150,000 m(3)/day MAR system is proposed as an economic solution to solve part of the environmental and water supply issues. Groundwater modeling has demonstrated that the injection of about 150,000 m(3)/day into the Avon Park High Permeable Zone will result in the creation of a 1000 m wide plume of fresh and brackish-water (due to mixing) extending across the water short area over a 10-year period. The operational cost of the MAR injection system would be less than $0.106/m(3) and the environmental benefits would alone more than cover this cost in the long term. In addition, the future unit water supply cost to the consumer would be reduced from $1 to $1.25/m(3) to $0.45 to $0.65/m(3).
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Date Issued: 2017-10-11
Identifier: 10.3390/w9100774, fgcu_ir_000032, http://www.mdpi.com/2073-4441/9/10/774
Format: Citation

Title: Measuring Groundwater and contaminant Flux: passive Flux Meter Field Applications and Issues with Alcohol Degradability.
Creator: Bondehagen, Diane
Abstract/Description: The passive flux meter (PFM) developed at the University of Florida is an innovative device that is inserted into a well in order to measure groundwater and contaminant flux. The in-situ device consists of an activated carbon matrix impregnated with known amounts of alcohols that are desorbed at rates proportional to the groundwater flux through the device. After exposure the sorbent is extracted to quantify the contaminant mass intercepted and the resident alcohol mass remaining. Since the...
Show moreThe passive flux meter (PFM) developed at the University of Florida is an innovative device that is inserted into a well in order to measure groundwater and contaminant flux. The in-situ device consists of an activated carbon matrix impregnated with known amounts of alcohols that are desorbed at rates proportional to the groundwater flux through the device. After exposure the sorbent is extracted to quantify the contaminant mass intercepted and the resident alcohol mass remaining. Since the alcohols employed in bioactive sites are degradable, studies were conducted to investigate biodegradation issues and microbial acclimation times in eld application. Also, silver-impregnated activated carbon was compared to unamended activated carbon in batch and column studies to determine silver ion effects on degradation. The studies confirm degradation and microbial acclimation occurrence, and demonstrate that silver impregnated activated carbon does inhibit degradation. Issues remain with biofilm/biofouling observed in the field as well as column studies.
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Date Issued: 2010
Identifier: fgcu_ir_000037
Format: Document (PDF)

Title: Crossover study of amputee stair ascent and descent biomechanics using Genium and C-Leg prostheses with comparison to non-amputee control.
Creator: Lura, Derek J., Wernke, Matthew W., Carey, Stephanie L., Kahle, Jason T., Miro, Rebecca M., Highsmith, M. Jason
Abstract/Description: This study was a randomized crossover of stair ambulation of Transfemoral Amputees (TFAs) using the Genium and C-Leg prosthetic knees. TFAs typically have difficulty ascending and descending stairs, limiting community mobility. The objective of this study was to determine the relative efficacy of the Genium and C-Leg prostheses for stair ascent and descent, and their absolute efficacy relative to non-amputees. Twenty TFAs, and five non-amputees participated in the study. TFAs were randomized...
Show moreThis study was a randomized crossover of stair ambulation of Transfemoral Amputees (TFAs) using the Genium and C-Leg prosthetic knees. TFAs typically have difficulty ascending and descending stairs, limiting community mobility. The objective of this study was to determine the relative efficacy of the Genium and C-Leg prostheses for stair ascent and descent, and their absolute efficacy relative to non-amputees. Twenty TFAs, and five non-amputees participated in the study. TFAs were randomized to begin the study with the Genium or C-Leg prosthesis. Informed consent was obtained from all participants prior to data collection and the study was listed on clinicaltrials.gov (#NCT01473662). After fitting, accommodation, and training, participants were asked to demonstrate their preferred gait pattern for stair ascent and descent and a step-over-step pattern if able. TFAs then switched prosthetic legs and repeated fitting, accommodation, training, and testing. An eight camera Vicon optical motion analysis system, and two AMTI force plates were used to track and analyze the participants’ gait patterns, knee flexion angles, knee moment normalized by body weight, and swing time. For stair descent, no significant differences were found between prostheses. For stair ascent, Genium use resulted in: increased ability to use a step-over-step gait pattern (p = 0.03), increased prosthetic side peak knee flexion (p < 0.01), and increased swing duration (p < 0.01). Changes in contralateral side outcomes and in knee moment were not significant. Overall the Genium knee decreased deficiency in gait patterns for stair ascent relative to the C-Leg, by enabling gait patterns that more closely resembled non-amputees.
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Date Issued: 2017-10
Identifier: 10.1016/j.gaitpost.2017.07.114, fgcu_ir_001008, https://linkinghub.elsevier.com/retrieve/pii/S0966636217308251
Format: Citation

Title: Nanostructured Semiconducting Polymer Films with Enhanced Crystallinity and Reorientation of Crystalline Domains by Electrospray Deposition.
Creator: Johnston, Danvers, Rodriguez, Johan C., Tao, Zui, Mi, Bao-Xiu, Deng, Weiwei, Zhao, Xin-Yan
Abstract/Description: Self‐organization of conjugated polymer such as poly(3‐hexylthiophene) (P3HT) causes directional anisotropy in the charge carrier mobility. In contrast to an edge‐on orientation formed in thin films of P3HT made by spin coating, in this study electrospray deposition rotates the orientation while producing nanopillar structures as a result of Coulombic fission and significant evaporation of solvent from the droplets. The nanostructured films are investigated by scanning electron microscopy....
Show moreSelf‐organization of conjugated polymer such as poly(3‐hexylthiophene) (P3HT) causes directional anisotropy in the charge carrier mobility. In contrast to an edge‐on orientation formed in thin films of P3HT made by spin coating, in this study electrospray deposition rotates the orientation while producing nanopillar structures as a result of Coulombic fission and significant evaporation of solvent from the droplets. The nanostructured films are investigated by scanning electron microscopy. Due to substantial polymer–air interfaces oriented perpendicular to the substrate, P3HT molecules adopt a face‐on orientation with respect to the substrate plane that is confirmed by grazing incidence X‐ray diffraction. Additionally, enhanced crystallinity (29% increase) is confirmed by a redshift in the UV–vis absorption spectra. Because deposition by electrospray is a scalable nanomanufacturing method, these results inform the design of low‐cost device layers for large‐surface‐area applications such as light emitting diodes and photovoltaics.
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Date Issued: 2017-05-22
Identifier: fgcu_ir_001011
Format: Citation

Title: Experimental Measurement of Diffusive Extinction Depth and Soil Moisture Gradients in a Dune Sand Aquifer in Western Saudi Arabia: Assessment of Evaporation Loss for Design of an MAR System.
Creator: Mughal, Iqra, Jadoon, Khan, Mai, P., Al-Mashharawi, Samir, Missimer, Thomas
Abstract/Description: A component of designing a managed aquifer recharge system in a dune aquifer is the control of diffusive evaporative loss of water which is governed by the physical properties of the sediments and the position of the water table. A critical water table position is the “extinction depth”, below which no further loss of water occurs via diffusion. Field experiments were conducted to measure the extinction depth of sediments taken from a typical dune field in the region. The soil grain size...
Show moreA component of designing a managed aquifer recharge system in a dune aquifer is the control of diffusive evaporative loss of water which is governed by the physical properties of the sediments and the position of the water table. A critical water table position is the “extinction depth”, below which no further loss of water occurs via diffusion. Field experiments were conducted to measure the extinction depth of sediments taken from a typical dune field in the region. The soil grain size characteristics, laboratory porosity, and saturated hydraulic conductivity were measured. The sand is classified as well-sorted, very fine sand with a mean grain diameter of 0.15 mm. Soil moisture gradients and diffusion loss rates were measured using sensors in a non-weighing lysimeter that was placed below land surface. The sand was saturated carefully with water from the bottom to the top and was exposed to the natural climate for a period of about two months. The moisture gradient showed a gradual decline during measurement until extinction depth was reached at about 100 cm below surface after 56 days. Diurnal temperature changes were observed in the upper 75 cm of the column and were negligible at greater depth.
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Date Issued: 2015-12-10
Identifier: 10.3390/w7126669, fgcu_ir_000081, http://www.mdpi.com/2073-4441/7/12/6669
Format: Citation

Title: Managed Aquifer Recharge (MAR) Economics for Wastewater Reuse in Low Population Wadi Communities, Kingdom of Saudi Arabia.
Creator: Missimer, Thomas, Maliva, Robert, Ghaffour, Noreddine, Leiknes, TorOve, Amy, Gary
Abstract/Description: Depletion of water supplies for potable and irrigation use is a major problem in the rural wadi valleys of Saudi Arabia and other areas of the Middle East and North Africa. An economic analysis of supplying these villages with either desalinated seawater or treated wastewater conveyed via a managed aquifer recharge (MAR) system was conducted. In many cases, there are no local sources of water supply of any quality in the wadi valleys. The cost per cubic meter for supplying desalinated water...
Show moreDepletion of water supplies for potable and irrigation use is a major problem in the rural wadi valleys of Saudi Arabia and other areas of the Middle East and North Africa. An economic analysis of supplying these villages with either desalinated seawater or treated wastewater conveyed via a managed aquifer recharge (MAR) system was conducted. In many cases, there are no local sources of water supply of any quality in the wadi valleys. The cost per cubic meter for supplying desalinated water is $2–5/m3 plus conveyance cost, and treated wastewater via an MAR system is $0–0.50/m3 plus conveyance cost. The wastewater reuse, indirect for potable use and direct use for irrigation, can have a zero treatment cost because it is discharged to waste in many locations. In fact, the economic loss caused by the wastewater discharge to the marine environment can be greater than the overall amortized cost to construct an MAR system, including conveyance pipelines and the operational costs of reuse in the rural environment. The MAR and associated reuse system can solve the rural water supply problem in the wadi valleys and reduce the economic losses caused by marine pollution, particularly coral reef destruction.
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Date Issued: 2014-08-07
Identifier: 10.3390/w6082322, fgcu_ir_000074, http://www.mdpi.com/2073-4441/6/8/2322
Format: Citation

Title: Anthropogenic-Induced Changes in the Mechanism of Drylands Ephemeral Stream Recharge, Western Saudi Arabia.
Creator: Jadoon, Khan, Al-Mashharawi, Samir, Hanafy, Sherif, Schuster, Gerard, Missimer, Thomas
Abstract/Description: Wadi aquifers in Saudi Arabia historically have been recharged primarily by channel loss (infiltration) during floods. Historically, seasonal groundwater levels fluctuated from land surface to about 3 m below the surface. Agricultural irrigation pumping has lowered the water table up to 35 m below the surface. The geology surrounding the fluvial system at Wadi Qidayd consists of pelitic Precambrian rocks that contribute sediments ranging in size from mud to boulders to the alluvium. Sediments...
Show moreWadi aquifers in Saudi Arabia historically have been recharged primarily by channel loss (infiltration) during floods. Historically, seasonal groundwater levels fluctuated from land surface to about 3 m below the surface. Agricultural irrigation pumping has lowered the water table up to 35 m below the surface. The geology surrounding the fluvial system at Wadi Qidayd consists of pelitic Precambrian rocks that contribute sediments ranging in size from mud to boulders to the alluvium. Sediments within the wadi channel consist of fining upward, downstream-dipping beds, causing channel floodwaters to pass through several sediment sequences, including several mud layers, before it can reach the water table. Investigation of the wadi aquifer using field observation, geological characterization, water-level monitoring, geophysical profiles, and a hypothetical model suggests a critical water level has been reached that affects the recharge of the aquifer. The wetted front can no longer reach the water table due to the water uptake in the wetting process, downstream deflection by the clay layers, and re-emergence of water at the surface with subsequent direct and diffusive evaporative loss, and likely uptake by deep-rooted acacia trees. In many areas of the wadi system, recharge can now occur only along the channel perimeter via fractured rocks that are in direct horizontal hydraulic connection to the permeable beds above and below the water table.
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Date Issued: 2016-04-07
Identifier: 10.3390/w8040136, fgcu_ir_000091, http://www.mdpi.com/2073-4441/8/4/136
Format: Citation

Title: Backreef and beach carbonate sediments of the Red Sea, Saudi Arabia: impacts of reef geometry and currents on sediment composition.
Creator: Missimer, Thomas M., Al-Mashharawi, S., Dehwah, A. H. A., Coulibaly, K.
Abstract/Description: Three sites in the Red Sea were investigated to assess the variability of composition in Holocene sediments of the backreef environment within 0–2 m of water depth. This is important because composition of the sediment is commonly used to estimate water depth in ancient carbonate rocks. The site located at the King Abdullah Economic City (Saudi Arabia) contains a fringing reef with the reef tract located very close to the beach at the north end, flaring to the south to produce a narrower...
Show moreThree sites in the Red Sea were investigated to assess the variability of composition in Holocene sediments of the backreef environment within 0–2 m of water depth. This is important because composition of the sediment is commonly used to estimate water depth in ancient carbonate rocks. The site located at the King Abdullah Economic City (Saudi Arabia) contains a fringing reef with the reef tract located very close to the beach at the north end, flaring to the south to produce a narrower backreef area compared to the other two sites. This geometry produces a north to south current with a velocity of up to 15 cm s−1, particularly during high onshore winds. The sediments contain predominantly non-skeletal grains, including peloids, coated grains, ooids, and grapestones that form on the bottom. The percentage of coralgal grains in the sediment was significantly lower than at the other two sites studied. Om Al Misk Island and Shoaiba have a much lower-velocity current within the backreef zone and contain predominantly coralgal sediments from the beach to the landward edge of the reef tract. The two locations containing the predominantly coralgal microfacies were statistically similar, but the King Abdullah Economic City site was statistically different despite having a similar water depth profile. Slight differences in reef configuration, including reef orientation and distance from the shore, can produce considerable differences in sediment thickness and composition within the backreef environment, which should induce caution in the interpretation of water depth in ancient carbonate rocks using composition.
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Date Issued: 2017-12-01
Identifier: 10.1007/s00338-017-1607-4, fgcu_ir_000035, http://link.springer.com/10.1007/s00338-017-1607-4
Format: Citation

Title: Seabed gallery intakes: Investigation of the water pretreatment effectiveness of the active layer using a long-term column experiment.
Creator: Missimer, Thomas M., Dehwah, Abdullah H.A.
Abstract/Description: Seabed gallery intake systems used for seawater reverse osmosis facilities employ the same principle of water treatment as slow sand filtration in freshwater systems. An investigation concerning the effectiveness of the active layer (top layer) in improving raw water quality was conducted by using a long-term bench-scale columns experiment. Two different media types, silica and carbonate sand, were tested in 1 m columns to evaluate the effectiveness of media type in terms of algae, bacteria,...
Show moreSeabed gallery intake systems used for seawater reverse osmosis facilities employ the same principle of water treatment as slow sand filtration in freshwater systems. An investigation concerning the effectiveness of the active layer (top layer) in improving raw water quality was conducted by using a long-term bench-scale columns experiment. Two different media types, silica and carbonate sand, were tested in 1 m columns to evaluate the effectiveness of media type in terms of algae, bacteria, Natural Organic Matter (NOM) and Transparent Exopolymer Particles (TEP) removal over a period of 620 days. Nearly all algae in the silica sand column, 87% (σ = 0.04) of the bacteria, 59% (σ = 0.11) of the biopolymer fraction of NOM, 59% (σ = 0.16) of particulate and 32% (σ = 0.25) of colloidal TEP were removed during the last 330 days of the experiment. Total removal was observed in the carbonate sand column for algal concentration, while the bacterial removal was lower at 74% (σ = 0.08). Removal of biopolymers, particulate and colloidal TEP were higher in the carbonate column during the last 330 days with 72% (σ = 0.15), 66% (σ = 0.08) and 36% (σ = 0.12) removed for these organics respectively. Removal of these key organics through the 1 m thick column, representing the active layer, will likely reduce the rate of biofouling, reduce chemical usage and minimize operating cost in SWRO systems. The data show that the media will require several months at the beginning of operation to reach equilibrium so that high organic removal rates can be achieved. No development of a “schmutzdecke” layer occurred. The experimental results suggest that unlike freshwater slow sand filtration wherein most water treatment occurs in the upper 10 cm, in seawater systems treatment occurs throughout the full active layer depth of 1 m. The results of this study will help in designing and operating seabed gallery intake systems in varied geological conditions.
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Date Issued: 2017-05-10
Identifier: fgcu_ir_001009
Format: Citation

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