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Full-Text Articles in Engineering

Stomatal Conductance Measurement For Toxicity Assessment In Zero-Effluent Constructed Wetlands: Effects Of Landfill Leachate On Hydrophytes, Andrzej Białowiec, Jacek A. Koziel, Piotr Manczarski Feb 2019

Stomatal Conductance Measurement For Toxicity Assessment In Zero-Effluent Constructed Wetlands: Effects Of Landfill Leachate On Hydrophytes, Andrzej Białowiec, Jacek A. Koziel, Piotr Manczarski

Agricultural and Biosystems Engineering Publications

In this research, we explore for the first time the use of leaf stomatal conductance (gs) for phytotoxicity assessment. Plants respond to stress by regulating transpiration. Transpiration can be correlated with stomatal conductance when the water vapor pressure gradient for transpiration is constant. Thus, our working hypothesis was that the gs measurement could be a useful indicator of the effect of toxic compounds on plants. This lab-scale study aimed to test the measurement of gs as a phytotoxicity indicator. Our model plants were two common hydrophytes used in zero-effluent constructed wetlands for treating landfill leachate. The toxic influence of two ...


Development Of Time-Weighted Average Sampling Of Odorous Volatile Organic Compounds In Air With Solid-Phase Microextraction Fiber Housed Inside A Gc Glass Liner: Proof Of Concept, Madina Tursumbayeva, Jacek A. Koziel, Devin L. Maurer, Bulat Kenessov, Somchai Rice Jan 2019

Development Of Time-Weighted Average Sampling Of Odorous Volatile Organic Compounds In Air With Solid-Phase Microextraction Fiber Housed Inside A Gc Glass Liner: Proof Of Concept, Madina Tursumbayeva, Jacek A. Koziel, Devin L. Maurer, Bulat Kenessov, Somchai Rice

Agricultural and Biosystems Engineering Publications

Finding farm-proven, robust sampling technologies for measurement of odorous volatile organic compounds (VOCs) and evaluating the mitigation of nuisance emissions continues to be a challenge. The objective of this research was to develop a new method for quantification of odorous VOCs in air using time-weighted average (TWA) sampling. The main goal was to transform a fragile lab-based technology (i.e., solid-phase microextraction, SPME) into a rugged sampler that can be deployed for longer periods in remote locations. The developed method addresses the need to improve conventional TWA SPME that suffers from the influence of the metallic SPME needle on the ...


Enhancing The Co-Utilization Of Biomass-Derived Mixed Sugars By Yeasts, Meirong Gao, Deon Ploessl, Zengyi Shao Jan 2019

Enhancing The Co-Utilization Of Biomass-Derived Mixed Sugars By Yeasts, Meirong Gao, Deon Ploessl, Zengyi Shao

Chemical and Biological Engineering Publications

Plant biomass is a promising carbon source for producing value-added chemicals, including transportation biofuels, polymer precursors, and various additives. Most engineered microbial hosts and a select group of wild-type species can metabolize mixed sugars including oligosaccharides, hexoses, and pentoses that are hydrolyzed from plant biomass. However, most of these microorganisms consume glucose preferentially to non-glucose sugars through mechanisms generally defined as carbon catabolite repression. The current lack of simultaneous mixed-sugar utilization limits achievable titers, yields, and productivities. Therefore, the development of microbial platforms capable of fermenting mixed sugars simultaneously from biomass hydrolysates is essential for economical industry-scale production, particularly for ...


Observational Time Series For Lakes Azuei And Enriquillo: Surface Area, Volume, And Elevation, Mahrokh Moknatian, Michael Piasecki Jan 2019

Observational Time Series For Lakes Azuei And Enriquillo: Surface Area, Volume, And Elevation, Mahrokh Moknatian, Michael Piasecki

Publications and Research

In this report, we present historical time series of surface area, volume, and elevation for lakes Azuei (Haiti) and Enriquillo (Dominican Republic). The intention is to present a history of the lakes’ levels for both bodies of water as derived from Landsat imagery that is augmented by reports and narratives that reach further back in time. We also summarize lake level time series data collected and developed through various other efforts and compare these data sets to our time series. The time series contains 45 years’ worth of data ranging from 1972 to 2017 which we developed from Landsat imagery ...


Notes On The Gridlab-D Household Equivalent Thermal Parameter Model, Leigh Tesfatsion, Swathi Battula Jan 2019

Notes On The Gridlab-D Household Equivalent Thermal Parameter Model, Leigh Tesfatsion, Swathi Battula

Economics Working Papers

GridLab-D (GLD) is an agent-based platform, developed by researchers at Pacific Northwest National Laboratory, that permits users to accurately simulate the state dynamics of power distribution systems at time scales ranging from sub-seconds to years. The purpose of this study is to present, in careful comprehensive form, a complete analytical state-space control representation for a version of the GLD Household Equivalent Thermal Parameter Model as support documentation for model users. This model is a physically-based implementation of a household with multiple price-responsive and conventional appliances whose thermal dynamics are determined over successive days by resident appliance usage and external weather ...


An Airlifted Tidal Mesocosm For Oil Degradation Studies, Daniel Christopher Alt Jan 2019

An Airlifted Tidal Mesocosm For Oil Degradation Studies, Daniel Christopher Alt

LSU Doctoral Dissertations

Mesocosms were constructed to allow scientists to isolate variables in a microtidal marsh environment, mimicking the natural conditions found in Terrebonne Bay. The control offered by these mesocosms is given by a process control system that takes user inputs and automates water movement. Twelve mesocosms were constructed, each holding 4.02 m3 (142 ft3) of marsh soil and 3.88 m3 (137 ft3) of water to give 3 experimental levels and a control, all in triplicate.

Each mesocosms that was constructed contained marsh plants in soil plugs 9 feet in diameter and 3 feet deep. These ...


Modeled And Measured Ecosystem Respiration In Maize–Soybean Systems Over 10 Years, Ming Zhan, Adam Liska, Anthony Nguy-Robertson, Andrew E. Suyker, Matthew P. Pelton, Haishun Yang Jan 2019

Modeled And Measured Ecosystem Respiration In Maize–Soybean Systems Over 10 Years, Ming Zhan, Adam Liska, Anthony Nguy-Robertson, Andrew E. Suyker, Matthew P. Pelton, Haishun Yang

Adam Liska Papers

Crop residue is an abundant resource for the potential production of biofuels, but a better understanding of its use on net carbon emissions must be developed to mitigate climate change. This analysis combines two established crop growth models (Hybrid-Maize and SoySim) with a simple soil and crop residue respiration model to estimate daily ecosystem respiration (ERe) from maize and soybean; ERe was estimated to be the sum of CO2 emissions from the oxidation of the growing crop, crop residue, and soil organic carbon (SOC). Model-estimated CO2 fluxes from irrigated continuous maize and irrigated maize–soybean cropping systems in ...


Metabolic Engineering For Biocatalyst Robustness To Organic Inhibitors, Liam Royce, Laura R. Jarboe Jan 2019

Metabolic Engineering For Biocatalyst Robustness To Organic Inhibitors, Liam Royce, Laura R. Jarboe

Chemical and Biological Engineering Publications

Microbial production of biorenewable fuels and chemicals is often limited by inhibition of the biocatalyst, either by increasing concentrations of the product compound or by contaminant compounds in the biomass‐derived sugars. This inhibition can interfere with economically viable production. Here we discuss typical mechanisms of inhibition and methods for improving biocatalyst robustness. Inhibition often takes the form of inhibition of enzyme activity, depletion of cofactor pools, and membrane damage; methods are discussed for mitigating each of these types of inhibition. Various evolutionary schemes have been developed and implemented on a variety of inhibitory compounds, including butanol, acetic acid, furfural ...


Waste To Carbon: Influence Of Structural Modification On Voc Emission Kinetics From Stored Carbonized Refuse-Derived Fuel, Andrzej Białowiec, Monika Micuda, Antoni Szumny, Jacek Łyczko, Jacek A. Koziel Jan 2019

Waste To Carbon: Influence Of Structural Modification On Voc Emission Kinetics From Stored Carbonized Refuse-Derived Fuel, Andrzej Białowiec, Monika Micuda, Antoni Szumny, Jacek Łyczko, Jacek A. Koziel

Agricultural and Biosystems Engineering Publications

The torrefaction of municipal solid waste is one of the solutions related to the Waste to Carbon concept, where high-quality fuel—carbonized refuse-derived fuel (CRDF)—is produced. An identified potential problem is the emission of volatile organic compounds (VOCs) during CRDF storage. Kinetic emission parameters have not yet been determined. It was also shown that CRDF can be pelletized for energy densification and reduced volume during storage and transportation. Thus, our working hypothesis was that structural modification (via pelletization) might mitigate VOC emissions and influence emission kinetics during CRDF storage. Two scenarios of CRDF structural modification on VOC emission kinetics ...


Torrefaction Of Sewage Sludge: Kinetics And Fuel Properties Of Biochars, Jakub Pulka, Piotr Manczarski, Jacek A. Koziel, Andrzej Białowiec Jan 2019

Torrefaction Of Sewage Sludge: Kinetics And Fuel Properties Of Biochars, Jakub Pulka, Piotr Manczarski, Jacek A. Koziel, Andrzej Białowiec

Agricultural and Biosystems Engineering Publications

We propose a ‘Waste to Carbon’ thermal transformation of sewage sludge (SS) via torrefaction to a valuable product (fuel) with a high content of carbon. One important, technological aspect to develop this concept is the determination of activation energy needed for torrefaction. Thus, this research aimed to evaluate the kinetics of SS torrefaction and determine the effects of process temperature on fuel properties of torrefied products (biochars). Torrefaction was performed using high ash content SS at six (200~300 °C) temperatures and 60 min residence (process) time. Mass loss during torrefaction ranged from 10~20%. The resulting activation energy for ...


Call For Abstracts - Resrb 2019, July 8-9, Wrocław, Poland, Wojciech M. Budzianowski Dec 2018

Call For Abstracts - Resrb 2019, July 8-9, Wrocław, Poland, Wojciech M. Budzianowski

Wojciech Budzianowski

No abstract provided.


Catchment-Scale Phosphorus Export Through Surface And Drainage Pathways, Conrad E. Brendel, Michelle L. Soupir, Leigh Ann M. Long, Matthew J. Helmers, Charles D. Ikenberry, Amy L. Kaleita Dec 2018

Catchment-Scale Phosphorus Export Through Surface And Drainage Pathways, Conrad E. Brendel, Michelle L. Soupir, Leigh Ann M. Long, Matthew J. Helmers, Charles D. Ikenberry, Amy L. Kaleita

Agricultural and Biosystems Engineering Publications

The site-specific nature of P fate and transport in drained areas exemplifies the need for additional data to guide implementation of conservation practices at the catchment scale. Total P (TP), dissolved reactive P (DRP), and total suspended solids (TSS) were monitored at five sites—two streams, two tile outlets, and a grassed waterway—in three agricultural subwatersheds (221.2–822.5 ha) draining to Black Hawk Lake in western Iowa. Median TP concentrations ranged from 0.034 to 1.490 and 0.008 to 0.055 mg P L−1 for event and baseflow samples, respectively. The majority of P ...


Quantification Of Voc Emissions From Carbonized Refuse-Derived Fuel Using Solid-Phase Microextraction And Gas Chromatography-Mass Spectrometry, Andrzej Białowiec, Monika Micuda, Antoni Szumny, Jacek Łyczko, Jacek A. Koziel Dec 2018

Quantification Of Voc Emissions From Carbonized Refuse-Derived Fuel Using Solid-Phase Microextraction And Gas Chromatography-Mass Spectrometry, Andrzej Białowiec, Monika Micuda, Antoni Szumny, Jacek Łyczko, Jacek A. Koziel

Agricultural and Biosystems Engineering Publications

In this work, for the first time, the volatile organic compound (VOC) emissions from carbonized refuse-derived fuel (CRDF) were quantified on a laboratory scale. The analyzed CRDF was generated from the torrefaction of municipal waste. Headspace solid-phase microextraction (SPME) and gas chromatography-mass spectrometry (GC-MS) was used to identify 84 VOCs, including many that are toxic, e.g., derivatives of benzene or toluene. The highest emissions were measured for nonanal, octanal, and heptanal. The top 10 most emitted VOCs contributed to almost 65% of the total emissions. The VOC mixture emitted from torrefied CRDF differed from that emitted by other types ...


Novel Materials Can Radically Improve Whole-System Environmental Impacts Of Additive Manufacturing, Jeremy Faludi, Cory M. Van Sice, Yuan Shi, Justin Bower, Owen M.K Brooks Dec 2018

Novel Materials Can Radically Improve Whole-System Environmental Impacts Of Additive Manufacturing, Jeremy Faludi, Cory M. Van Sice, Yuan Shi, Justin Bower, Owen M.K Brooks

Open Dartmouth: Faculty Open Access Articles

Additive manufacturing often has higher environmental impacts per part than traditional manufacturing at scale, but new materials can enable more sustainable 3D printing. This study developed and tested novel materials for paste extrusion printing, and tested materials invented by others. Testing compared their whole-system environmental impacts to standard ABS extrusion, measured by life cycle assessment (LCA); testing also assessed material strength, printability, and cost. Materials were chosen for low print energy (chemical bonding, not melting), low toxicity, and circular life cycle (biodegradable, ideally sourced from waste biomaterial). Printing energy was reduced 75% (from 160 to 40 Wh/part), and embodied ...


Assessing Biofiltration Without Ozonation For Removal Of Trihalomethane Precursors In Drinking Water At The Beaver Water District Drinking Water Treatment Plant, Sana Ajaz Dec 2018

Assessing Biofiltration Without Ozonation For Removal Of Trihalomethane Precursors In Drinking Water At The Beaver Water District Drinking Water Treatment Plant, Sana Ajaz

Theses and Dissertations

Biofiltration without pre-ozonation has the capability to remove natural organic matter (NOM) fractions that serve as precursors of disinfection byproducts (DBPs), which include the four regulated trihalomethanes (THMs) and dichloroacetonitrile (DCAN). Rapid small-scale column tests (RSSCTs) and Pilot Plant filters operated at empty-bed contact times (EBCTs) of 4, 8, and 16 minutes were used to evaluate the performance of nutrient-amended (free ammonia and phosphorus) biofiltration for THM and DCAN precursor removal, as measured using formation potential (FP) tests. NOM surrogates – which include dissolved organic carbon (DOC), specific ultraviolet absorbance (SUVA254) and fluorescence-PARAFAC components – were measured weekly throughout the 30-week study ...


Ncer Assistance Agreement Annual Progress Report For Grant #83582401 - Assessment Of Stormwater Harvesting Via Manage Aquifer Recharge (Mar) To Develop New Water Supplies In The Arid West: The Salt Lake Valley Example, R. Ryan Dupont, Joan E. Mclean, Richard Peralta, Sarah Null, Douglas B. Jackson-Smith Nov 2018

Ncer Assistance Agreement Annual Progress Report For Grant #83582401 - Assessment Of Stormwater Harvesting Via Manage Aquifer Recharge (Mar) To Develop New Water Supplies In The Arid West: The Salt Lake Valley Example, R. Ryan Dupont, Joan E. Mclean, Richard Peralta, Sarah Null, Douglas B. Jackson-Smith

Civil and Environmental Engineering Faculty Publications

The goals of the original proposed project remain the same, that is, to test the hypothesis that Managed Aquifer Recharge (MAR) for stormwater harvesting is a technically feasible, socially and environmentally acceptable, economically viable, and legally feasible option for developing new water supplies for arid Western urban ecosystems experiencing increasing population, and climate change pressures on existing water resources. The project is being carried out via three distinct but integrated components that include: 1) Monitoring of existing distributed MAR harvesting schemes involving a growing number of demonstration Green Infrastructure (GI) test sites; 2) Integrated stormwater/vadose zone/groundwater/ ecosystem services ...


Waste To Carbon: Densification Of Torrefied Refuse-Derived Fuel, Andrzej Białowiec, Monika Micuda, Jacek A. Koziel Nov 2018

Waste To Carbon: Densification Of Torrefied Refuse-Derived Fuel, Andrzej Białowiec, Monika Micuda, Jacek A. Koziel

Agricultural and Biosystems Engineering Publications

In this work, for the first time, the feasibility of obtaining carbonized refuse-derived fuel (CRDF) pelletization from municipal solid waste (MSW) was shown. Production of CRDF by torrefaction of MSW could be the future of recycling technology. The objective was to determine the applied pressure needed to produce CRDF pellets with compressive strength (CS) comparable to conventional biomass pellets. Also, the hypothesis that a binder (water glass (WG)) applied to CRDF as a coating can improve CS was tested. The pelletizing was based on the lab-scale production of CRDF pellets with pressure ranging from 8.5 MPa to 76.2 ...


Cost Benefit Analysis Of Led Vs Florescent Lighting, Kurtis Clark, Phillip Humphrey Nov 2018

Cost Benefit Analysis Of Led Vs Florescent Lighting, Kurtis Clark, Phillip Humphrey

Student Research

Over the last few years, the state of Oklahoma has been looking at ways to reduce expenses to address concerns about a budget deficit. There have been efforts made to reduce expenses due to the use of energy. It has been said, when the lights are on, work is getting done. Running lights is therefore the cost of doing business. Our research examines the question, “is there a way to provide better lighting while operating at a lower cost.” This research examines the current lighting at Southwestern State University, primarily fluorescent lighting (FL), and a cost benefit analysis of switching ...


Water, Energy, And Carbon Footprints Of Bioethanol From The U.S. And Brazil, Mesfin Mergia Mekonnen, Thiago L. Romanelli, Chittaranjan Ray, Arjen Y. Hoekstra, Adam Liska, Christopher M. U. Neale Nov 2018

Water, Energy, And Carbon Footprints Of Bioethanol From The U.S. And Brazil, Mesfin Mergia Mekonnen, Thiago L. Romanelli, Chittaranjan Ray, Arjen Y. Hoekstra, Adam Liska, Christopher M. U. Neale

Adam Liska Papers

Driven by biofuel policies, which aim to reduce greenhouse gas (GHG) emissions and increase domestic energy supply, global production and consumption of bioethanol have doubled between 2007 and 2016, with rapid growth in corn-based bioethanol in the U.S. and sugar cane-based bioethanol in Brazil. Advances in crop yields, energy use efficiency in fertilizer production, biomass-to-ethanol conversion rates, and energy efficiency in ethanol production have improved the energy balance and GHG emission reduction potential of bioethanol. In the current study, the water, energy, and carbon footprints of bioethanol from corn in the U.S. and sugar cane in Brazil were ...


Fractionation And Characterization Of Lignin Streams From Unique High-Lignin Content Endocarp Feedstocks, Wenqi Li, Kirtley Amos, Mi Li, Yunqiao Pu, Seth Debolt, Arthur J. Ragauskas, Jian Shi Nov 2018

Fractionation And Characterization Of Lignin Streams From Unique High-Lignin Content Endocarp Feedstocks, Wenqi Li, Kirtley Amos, Mi Li, Yunqiao Pu, Seth Debolt, Arthur J. Ragauskas, Jian Shi

Biosystems and Agricultural Engineering Faculty Publications

Background: Lignin is a promising source of building blocks for upgrading to valuable aromatic chemicals and materials. Endocarp biomass represents a non-edible crop residue in an existing agricultural setting which cannot be used as animal feed nor soil amendment. With significantly higher lignin content and bulk energy density, endo-carps have significant advantages to be converted into both biofuel and bioproducts as compared to other biomass resources. Deep eutectic solvent (DES) is highly effective in fractionating lignin from a variety of biomass feedstocks with high yield and purity while at lower cost comparing to certain ionic liquids.

Results: In the present ...


The Challenges Of Geotechnical Exploration In Bangladesh For Sustainable Urban Development And Risk Reductions In Engineering Geology, Mir Fazul Karim, Nazrul I. Khandaker, Muhammad Qumrul Hasson, A.T.M. Shakhawat Hossain Nov 2018

The Challenges Of Geotechnical Exploration In Bangladesh For Sustainable Urban Development And Risk Reductions In Engineering Geology, Mir Fazul Karim, Nazrul I. Khandaker, Muhammad Qumrul Hasson, A.T.M. Shakhawat Hossain

Publications and Research

Bangladesh is a unique example of rapid urbanization where the urban population increased from 5 to 58 million in last four decades. Due to complex geology and active tectonic setting, the urban ground is impacted by fluvio-deltaic processes and regional seismicity. The densely populated cities of the country are facing risks from many natural hazards like floods, tidal surge, riverbank and coastal erosion, scour, landslides, soil collapse and foundation failures. Geologists anticipate severe seismic threats from yet-undefined tectonic structures and seek to determine their consequential geo-structural responses and conformance to the national building code. With rapid growth, demands on infrastructure ...


Selective Glucose Isomerization To Fructose Via Nitrogen-Doped Solid Base Catalyst Derived From Spent Coffee Grounds, Season S. Chen, Iris K.M. Yu, Dong-Wan Cho, Hocheol Song, Daniel C.W. Tsang, Jean-Philippe Tessonnier, Yong Sik Ok, Chi Sun Poon Oct 2018

Selective Glucose Isomerization To Fructose Via Nitrogen-Doped Solid Base Catalyst Derived From Spent Coffee Grounds, Season S. Chen, Iris K.M. Yu, Dong-Wan Cho, Hocheol Song, Daniel C.W. Tsang, Jean-Philippe Tessonnier, Yong Sik Ok, Chi Sun Poon

Chemical and Biological Engineering Publications

In this work, glucose isomerization to fructose was conducted via a solid base biochar catalyst derived from spent coffee grounds and melamine. The X-ray photoelectron spectroscopy (XPS) spectra identified the majority of pyridinic nitrogen on the biochar surface, which imparted the strong base character of the catalyst. Activity of the catalyst was evidenced by fast conversion of glucose (12%) and high selectivity to fructose (84%) in 20 min at a moderate temperature (120 °C) compared to recently reported immobilized tertiary amines at comparable N concentrations (10-15 mol% relative to glucose). By increasing the reaction temperature to 160 °C, fructose yield ...


Photocatalytic Activity: Experimental Features To Report In Heterogeneous Photocatalysis, Md. Ariful Hoque, Marcelo I. Guzman Oct 2018

Photocatalytic Activity: Experimental Features To Report In Heterogeneous Photocatalysis, Md. Ariful Hoque, Marcelo I. Guzman

Chemistry Faculty Publications

Heterogeneous photocatalysis is a prominent area of research with major applications in solar energy conversion, air pollution mitigation, and removal of contaminants from water. A large number of scientific papers related to the photocatalysis field and its environmental applications are published in different journals specializing in materials and nanomaterials. However, many problems exist in the conception of papers by authors unfamiliar with standard characterization methods of photocatalysts as well as with the procedures needed to determine photocatalytic activities based on the determination of “apparent quantum efficiencies” within a wavelength interval or “apparent quantum yields” in the case of using monochromatic ...


Transactive Energy Design For Integrated Transmission And Distribution Systems, Hieu Trung Nguyen, Swathi Battula, Rohit Reddy Takkala, Zhaoyu Wang, Leigh Tesfatsion Oct 2018

Transactive Energy Design For Integrated Transmission And Distribution Systems, Hieu Trung Nguyen, Swathi Battula, Rohit Reddy Takkala, Zhaoyu Wang, Leigh Tesfatsion

Economics Working Papers

The increasing deployment of distributed energy resources (DERs) is disrupting every aspect of power system operations, from retail distribution to wholesale production and transmission. This paper reports on the development of an agentbased test system enabling the study of new transactive energy system (TES) designs to ensure the reliable efficient operation of integrated transmission and distribution (ITD) systems with growing DER penetration. This ITD test system is used to explore the ability of a non-profit Distribution System Operator (DSO), participating within an ITD system, to use an innovative TES design to manage the power usage of DER devices in accordance ...


Spatial Structuring Of Cellulase Gene Abundance And Activity In Soil, Jinlyung Choi, Elizabeth Bach, Jaejin Lee, Jared Flater, Shane Dooley, Adina Howe, Kirsten S. Hofmockel Oct 2018

Spatial Structuring Of Cellulase Gene Abundance And Activity In Soil, Jinlyung Choi, Elizabeth Bach, Jaejin Lee, Jared Flater, Shane Dooley, Adina Howe, Kirsten S. Hofmockel

Agricultural and Biosystems Engineering Publications

Microbial mechanisms controlling cellulose degradation in soil habitats remains a critical knowledge gap in understanding and modeling terrestrial carbon-cycling. We investigated land management and soil micro-habitat influences on soil bacterial communities and distribution of cellulose-degrading enzyme genes in three bioenergy cropping systems (corn, prairie, and fertilized prairie). Within the soil, aggregates have been examined as potential micro- habitats with specific characteristics influencing resource partitioning and regulation, thus we also investigated genes associated with cellulose degradation within soil aggregate fractions from the fertilized prairie system. Soil bacterial communities and carbon-cycling gene presence varied across land management and soil microhabitats. Examination of ...


Monitoring And Evaluating The Influences Of Class V Injection Wells On Urban Karst Hydrology, James Adam Shelley Oct 2018

Monitoring And Evaluating The Influences Of Class V Injection Wells On Urban Karst Hydrology, James Adam Shelley

Masters Theses & Specialist Projects

The response of a karst aquifer to storm events is often faster and more severe than that of a non-karst aquifer. This distinction is often problematic for planners and municipalities, because karst flooding does not typically occur along perennial water courses; thus, traditional flood management strategies are usually ineffective. The City of Bowling Green (CoBG), Kentucky is a representative example of an area plagued by karst flooding. The CoBG, is an urban karst area (UKA), that uses Class V Injection Wells to lessen the severity of flooding. The overall effectiveness, siting, and flooding impact of Injection Wells in UKA’s ...


Characterization And Evaluation Of Cordless Nailer Performance For Liquid And Gaseous Fuels, Mark Carioscio Oct 2018

Characterization And Evaluation Of Cordless Nailer Performance For Liquid And Gaseous Fuels, Mark Carioscio

Master's Theses (2009 -)

The Paslode Cordless XP Framing Nailer is a combustion-powered nail gun that operates using a fuel blend of a propylene and 1-butene. This tool is designed to drive nails using a piston driven by a combustion reaction. The current fuel blend is able to fire approximately 1200 shots per fuel cartridge and match the energy output of pneumatic, corded nailers on the market. This thesis is written with the intent to gain a better understanding of the operation of the tool and how its performance varies when the fuel source is altered. A bizonal combustion model was created to simulate ...


What You Don’T See, Brent Sturlaugson Sep 2018

What You Don’T See, Brent Sturlaugson

Architecture Faculty Publications

Follow the supply chains of architecture and you’ll find not just product manufacturers but also environmental polluters and elusive networks of financial power and political influence.


Exploring Multiple Operating Scenarios To Identify Low-Cost, High Nitrate Removal Strategies For Electrically-Stimulated Woodchip Bioreactors, Ji-Yeow Law, Michelle L. Soupir, D. Raj Raman, Thomas Moorman Sep 2018

Exploring Multiple Operating Scenarios To Identify Low-Cost, High Nitrate Removal Strategies For Electrically-Stimulated Woodchip Bioreactors, Ji-Yeow Law, Michelle L. Soupir, D. Raj Raman, Thomas Moorman

Agricultural and Biosystems Engineering Publications

Woodchip bioreactors are recognized as an effective best management practice in the Iowa Nutrient Reduction Strategy. This edge-of-field practice intercepts and removes NO3-N, thereby reducing the NO3-N concentration in tile drainage before being discharged into surface water. Actual NO3-N load reductions realized by woodchip bioreactors are impacted by bioreactor size, hydraulic retention time (HRT), and denitrification efficiency. A typical woodchip bioreactor in Iowa may have 0.07% bioreactor area with respect to treatment area, 4–8 h HRT, and 43% mean denitrification efficiency. Here, we explored the potential of using electrically stimulated woodchip bioreactors to achieve greater NO3-N removal, and ...


Energy Use And Weatherization Practices: Applications For Agent-Based Modeling To Support Vulnerable Populations, Jacklin Stonewall, Wanyu Huang, Michael C. Dorneich, Caroline Krejci, Linda Shenk, Ulrike Passe Sep 2018

Energy Use And Weatherization Practices: Applications For Agent-Based Modeling To Support Vulnerable Populations, Jacklin Stonewall, Wanyu Huang, Michael C. Dorneich, Caroline Krejci, Linda Shenk, Ulrike Passe

Industrial and Manufacturing Systems Engineering Conference Proceedings and Posters

This work surveyed residents of an economically disadvantaged community on their attitudes toward weatherization and their energy use behaviors. To support urban leaders making decisions to mitigate the effects of large-scale climate change, data-driven simulation models are being developed. To ensure that these models are equitable, the needs of all citizens must be included, especially those most vulnerable to the impacts of climate change. The results of this survey indicate that residents are taking steps to weatherize and conserve energy, but they are hindered by a lack of resources and knowledge of available assistance programs. These results are being applied ...