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Air Force Institute of Technology

Civil and Environmental Engineering

2015

Articles 1 - 13 of 13

Full-Text Articles in Engineering

Comparison Of Novel Carboneous Structures To Treat Nitroaromatic Impacted Water, Benjamin M. Doane Dec 2015

Comparison Of Novel Carboneous Structures To Treat Nitroaromatic Impacted Water, Benjamin M. Doane

Theses and Dissertations

Carboneous materials such as carbon nanotube (CNT), granular activated carbon (GAC), and biochar are promising materials for the removal of organic contaminants from aqueous phase solutions. CNTs have astonishing mechanical strength, chemical and thermal stability and high surface area. While biochar, similar to GAC, having an extremely porous structure and high surface area, can be produced in more austere conditions with native materials. In this study, novel CNT-Hybrid structures (CNT-HS), hardwood pellet (HWP) Biochar and standard GAC (F-600 GAC) were used as adsorbents to treat water contaminated by a model nitroaromatic compound, 2,4-dinitrotoluene (DNT).

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Modeling Napl Dissolution From Pendular Rings In Idealized Porous Media, Junqi Huang, John A. Christ, Mark N. Goltz, Avery H. Demond Oct 2015

Modeling Napl Dissolution From Pendular Rings In Idealized Porous Media, Junqi Huang, John A. Christ, Mark N. Goltz, Avery H. Demond

Faculty Publications

The dissolution rate of nonaqueous phase liquid (NAPL) often governs the remediation time frame at subsurface hazardous waste sites. Most formulations for estimating this rate are empirical and assume that the NAPL is the nonwetting fluid. However, field evidence suggests that some waste sites might be organic wet. Thus, formulations that assume the NAPL is nonwetting may be inappropriate for estimating the rates of NAPL dissolution. An exact solution to the Young‐Laplace equation, assuming NAPL resides as pendular rings around the contact points of porous media idealized as spherical particles in a hexagonal close packing arrangement, is presented in this …

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A System Dynamics Approach To The Efficacy Of Oxime Therapy In Sub Lethal Exposure To Sarin Gas, Daniel J. Droste Jun 2015

A System Dynamics Approach To The Efficacy Of Oxime Therapy In Sub Lethal Exposure To Sarin Gas, Daniel J. Droste

Theses and Dissertations

The 2010 National Security Strategy states, The effective dissemination of a lethal agent would endanger the lives of thousands of people and have unprecedented economic, societal, and political consequences. We must continue to work at home with first responders and health officials to reduce the risk associated with high-consequence threats . Nerve agents, such as Sarin gas, are considered high consequence threats. The threat of use of agents such as Sarin is as much a threat today as any other time in our history. However, the suggested treatment protocol is not as precise as it could be. Debate exists over …

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Integrating Pavement Crack Detection And Analysis Using Autonomous Unmanned Aerial Vehicle Imagery, Patrick J. Grandsaert Mar 2015

Integrating Pavement Crack Detection And Analysis Using Autonomous Unmanned Aerial Vehicle Imagery, Patrick J. Grandsaert

Theses and Dissertations

Efficient, reliable data is necessary to make informed decisions on how to best manage aging road assets. This research explores a new method to automate the collection, processing, and analysis of transportation networks using Unmanned Aerial Vehicles and Computer Vision technology. While there are current methodologies to accomplish road assessment manually and semi-autonomously, this research is a proof of concept to obtain the road assessment faster and cheaper with a vision for little to no human interaction required. This research evaluates the strengths of applying UAV technology to pavement assessments and identifies where further work is needed. Furthermore, it validates …

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The Impact Of United States Investment For Civil Infrastructure In Developing Countries, Joel N. Hansen Mar 2015

The Impact Of United States Investment For Civil Infrastructure In Developing Countries, Joel N. Hansen

Theses and Dissertations

U.S. foreign assistance is used to support regional interests and to address the economic and social needs of host nation (HN) citizens. Within the Department of Defense (DoD), military exercises implement humanitarian and civic assistance (HCA) activities in developing nations as one method of accomplishing the U.S. foreign assistance objectives. To account for the impact of civil infrastructure projects on HN citizens, this research incorporated survey data collected during a DoD-sponsored exercise in Belize to test the expectancy disconfirmation model of citizen satisfaction and analyze the impact of constructing HCA projects on citizen satisfaction with HN government services. The research …

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Detection And Characterization Of Malathion Adherence To Piping Materials Used In Water Distribution Systems, William D. Flemings Mar 2015

Detection And Characterization Of Malathion Adherence To Piping Materials Used In Water Distribution Systems, William D. Flemings

Theses and Dissertations

Protection of the public water supply is a national security priority, and as such, it is important to better understand the fate of a chemical weapons agent injection into a public water distribution system. This study investigated the adherence of malathion to pipe materials that are used in public water distribution systems, with malathion serving as a chemical representative of the organophosphorus nerve agent VX. Copper and iron specimen were exposed to malathion solutions for periods of 4, 8, and 24 hours and then tested for evidence of chemical adherence to the metal surfaces. Nonlinear desiccation profiles revealed total mass …

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A Probabilistic Assessment Of Failure For Air Force Building Systems, Stephanie L. Alley Mar 2015

A Probabilistic Assessment Of Failure For Air Force Building Systems, Stephanie L. Alley

Theses and Dissertations

Deteriorating and failing federal facilities represent a cost to leaders and organizations as they attempt to manage and maintain these assets. Currently the Air Force employs the BUILDERTM Sustainment Management System to predict the reliability of building components. At different system levels, however, the probabilities of failure are not predicted. The purpose of this research is to provide probabilistic models which predict the probability of failure at the system level of a building s infrastructure hierarchy. This research investigated the plumbing, HVAC, fire protection, and electrical systems. Probabilistic models were created for these systems by using fault trees with …

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Effect Of Malathion On The Microbial Ecology Of Activated Sludge, Seth K. Martin Mar 2015

Effect Of Malathion On The Microbial Ecology Of Activated Sludge, Seth K. Martin

Theses and Dissertations

Decontamination activities may cause the release of contaminated washwater into the wastewater that eventually flows into a wastewater treatment facility. This raises concerns about the effect of chemical warfare agents (CWAs) on the microbial consortia that are responsible for cleaning the wastewater. This study investigated the impact of malathion on the microbial ecology of laboratory scale activated sludge communities. The Simpson Reciprocal Index decreased for three bioreactors operated in the absence of malathion, which showed that the microbial assemblage became less diverse during the course of the study. The species identified in the bioreactors belonged to well-known groups of heterotrophic …

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Test And Evaluation Of Ultrasonic Additive Manufacturing (Uam) For A Large Aircraft Maintenance Shelter (Lams) Baseplate, Daniel H. Gartland Mar 2015

Test And Evaluation Of Ultrasonic Additive Manufacturing (Uam) For A Large Aircraft Maintenance Shelter (Lams) Baseplate, Daniel H. Gartland

Theses and Dissertations

Additive manufacturing is an exciting new manufacturing technology that could have application to Air Force Civil Engineer (CE) operations. This research replicates a Large Area Maintenance Shelter (LAMS) baseplate design for ultrasonic additive manufacturing (UAM). Due to production problems the test section was not built as designed. Instead, a smaller block of material was submitted for evaluation. After the UAM build, ultrasonic inspection was conducted to identify anomalies in the test piece. The results of this proof of concept study indicate that UAM is not yet ready for CE expeditionary applications requiring a high degree of mechanical strength. The machine …

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Analysis Of Air Force Wartime Contracted Construction Project Performance, Ryan M. Hoff Mar 2015

Analysis Of Air Force Wartime Contracted Construction Project Performance, Ryan M. Hoff

Theses and Dissertations

Using a dataset of 25 Afghan wartime projects, two questions were investigated: 1) What factors affect the success of construction projects; and 2) How do project outcomes differ based on the contract type? Current literature suggests that wartime projects may face the same cost and schedule factors as peacetime projects, with some notable additions. Project factors, health and safety compliance, quality of work, technical performance, work productivity, and external environmental factors were tested with contingency tables to determine dependency with schedule or cost performance. External environmental factors, including weather and wartime security, were not predictive of project performance. However, cost …

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The Fate Of Malathion On Copper And Iron Piping Within A Water Distribution System, Walter R. Lee Mar 2015

The Fate Of Malathion On Copper And Iron Piping Within A Water Distribution System, Walter R. Lee

Theses and Dissertations

Thermogravimetry, the study of mass loss as a function of temperature, has been used for oxidation, decomposition, and solid-state studies. This research used a thermogravimetric analyzer (TGA) coupled with Fourier transform infrared (FT-IR) spectroscopy in the study of copper and iron specimens exposed to malathion. Exposure to the malathion solution created a visible silver coating on copper and graphite-flake particles on iron specimens. Thermogravimetric mass loss curves revealed linear and nonlinear decomposition stages associated with mass loss reactions. Copper specimens exposed to malathion exhibited lower activation energy (Ea) values (2.28 to 4.40 kJ mol-1) than for copper specimens exposed to …

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Pulsed Ultraviolet Light Emitting Diodes For Advanced Oxidation Of Tartrazine, Patrick M. Mudimbi Mar 2015

Pulsed Ultraviolet Light Emitting Diodes For Advanced Oxidation Of Tartrazine, Patrick M. Mudimbi

Theses and Dissertations

A study was conducted to evaluate the advanced oxidation of organic contaminants using pulsed ultraviolet light emitted diode (UV LED). Tartrazine was used as a surrogate organic compound. Low pressure Mercury-based lamps currently used in the treatment of water pose potential health risks if broken and create final disposal issues at the end of their service life. UV LED offers an alternative solution due to its non-toxicity, flexible design, and longer operating life compared to the mercury-based lamps. The apparent first order reaction rate constant for tartrazine degradation increased linearly with increasing duty cycle. At a continuous 100% duty cycle, …

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The Effect Of Malathion On The Activity And Performance Of Activated Sludge, Erik G. Rauglas Mar 2015

The Effect Of Malathion On The Activity And Performance Of Activated Sludge, Erik G. Rauglas

Theses and Dissertations

Decontamination activities following a chemical weapons incident may generate significant quantities of contaminated wash water that may enter the wastewater collection system either intentionally or accidentally. This raises concerns about the effect of chemical warfare agents (CWAs) on the operation of a biological wastewater treatment plant. The goal of the study was to evaluate the effect of malathion on the activity and performance of activated sludge. Malathion is an organophosphate (OP) and is considered an environmental surrogate for VX. This study employed respirometry, short term batch tests, and long term exposure experiments to investigate the effects of different concentrations of …

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