Civil and Environmental Engineering Commons^™

Cellulase Immobilization On Superparamagnetic Nanoparticles For Reuse In Cellulosic Biomass Conversion, Qing Song, Yu Mao, Mark Wilkins, Fernando Segato, Rolf Prade

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Current cellulosic biomass hydrolysis is based on the one-time use of cellulases. Cellulases immobilized on magnetic nanocarriers offer the advantages of magnetic separation and repeated use for continuous hydrolysis. Most immobilization methods focus on only one type of cellulase. Here, we report co-immobilization of two types of cellulases, β-glucosidase A (BglA) and cellobiohydrolase D (CelD), on sub-20 nm superparamagnetic nanoparticles. The nanoparticles demonstrated 100% immobilization efficiency for both BglA and CelD. The total enzyme activities of immobilized BglA and CelD were up to 67.1% and 41.5% of that of the free cellulases, respectively. The immobilized BglA and CelD each retained …

Switchgrass Storage Effects On The Recovery Of Carbohydrates After Liquid Hot Water Pretreatment And Enzymatic Hydrolysis, Noaa Frederick, Mengxing Li, Danielle Julie Carrier, Michael D. Buser, Mark R. Wilkins

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Perennial grasses that would be used for bioenergy and bioproducts production will need to be stored for various periods of time to ensure a continual feedstock supply to a bioprocessing facility. The effects of storage practices on grass composition and the response of grasses to subsequent bioprocesses such as pretreatment and enzymatic hydrolysis needs to be understood to develop the most efficient storage protocols. This study examined the effect of outdoor storage of round switchgrass bales on composition before and after liquid hot water pretreatment (LHW) and enzymatic hydrolysis. This study also examined the effect of washing LHW pretreated biomass …

Ecosystem Evapotranspiration: Challenges In Measurements, Estimates, And Modeling, D.M. Amatya, Sibel Irmak, P. Gowda, G. Sun, J.E. Nettles, K.R. Douglas-Mankin

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Evapotranspiration (ET) processes at the leaf to landscape scales in multiple land uses have important con- trols and feedbacks for local, regional, and global climate and water resource systems. Innovative methods, tools, and technologies for improved understanding and quantification of ET and crop water use are critical for adapting more effective management strategies to cope with increasing demand for freshwater resources under global climate change. This article introduces an ASABE Special Collection of 12 articles on ET monitoring and modeling research for multiple land uses and scales. The collection focuses on recent advances in four critical topical areas: (1) reference …

Critical Factors Affecting The Integration Of Biomass Gasification And Syngas Fermentation Technology, Karthikeyan D. Ramachandriya, Dimple K. Kundiyana, Ashokkumar M. Sharma, Ajay Kumar, Hasan K. Atiyeh, Raymond L. Huhnke, Mark R. Wilkins

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Gasification-fermentation is a thermochemical-biological platform for the production of fuels and chemicals. Biomass is gasified at high temperatures to make syngas, a gas composed of CO, CO2, H2, N2 and other minor components. Syngas is then fed to anaerobic microorganisms that convert CO, CO2 and H2 to alcohols by fermentation. This platform offers numerous advantages such as flexibility of feedstock and syngas composition and lower operating temperature and pressure compared to other catalytic syngas conversion processes. In comparison to hydrolysis-fermentation, gasification-fermentation has a major advantage of utilizing all organic components of biomass, including lignin, to yield higher fuel production. Furthermore, …

Heterogeneity Influences On Stream Water–Groundwater Interactions In A Gravel-Dominated Floodplain, R. B. Miller, Derek M. Heeren, Garey A. Fox, Todd Halihan, Daniel E. Storm

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Floodplains are composed of complex depositional patterns of ancient and recent stream sediments, and research is needed to address the manner in which coarse floodplain materials affect stream/groundwater exchange patterns. Efforts to understand the heterogeneity of aquifers have utilized numerous techniques typically focused on point-scale measurements; however, in highly heterogeneous settings, the ability to model heterogeneity is dependent on the data density and spatial distribution. The objective of this research was to investigate the correlation between broad-scale methodologies for detecting heterogeneity and the observed spatial variability in stream/groundwater interactions of gravel-dominated alluvial floodplains. More specifically, this study examined the correlation …

Incorporation Of Globally Available Datasets Into The Roving Cosmic-Ray Neutron Probe Method For Estimating Field-Scale Soil Water Content, William A. Avery, Catherine Finkenbiner, Trenton E. Franz, Tiejun Wang, Anthony L. Nguy-Robertson, Andrew E. Suyker, Timothy J. Arkebauer, Francisco Munoz-Arriola

Department of Agricultural and Biological Systems Engineering: Faculty Publications

The need for accurate, real-time, reliable, and multi-scale soil water content (SWC) monitoring is critical for a multitude of scientific disciplines trying to understand and predict the Earth’s terrestrial energy, water, and nutrient cycles. One promising technique to help meet this demand is fixed and roving cosmic-ray neutron probes (CRNPs). However, the relationship between observed low-energy neutrons and SWC is affected by local soil and vegetation calibration parameters. This effect may be accounted for by a calibration equation based on local soil type and the amount of vegetation. However, determining the calibration parameters for this equation is labor- and time-intensive, …

Potential Irrigation Reductions From Increasing Precipitation Utilization With Variable Rate Irrigation, Tsz Him Lo, Derek M. Heeren, Luciano Mateos, Joe D. Luck, Derrel L. Martin, Dean E. Eisenhauer

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Much of the previous research quantifying the potential benefits of variable rate irrigation (VRI) consists of case studies with simulations using data from small numbers of intensely sampled fields. In this study, an indicator of the amount of root zone available water capacity that is unutilized by uniform rate irrigation was calculated for 49,224 center pivot irrigated fields in Nebraska using publicly available data exclusively. Based on the values of this indicator, potential seasonal irrigation reductions from increasing precipitation utilization with VRI were estimated to be high for a small fraction of analyzed center pivots but low on a regional …

Evaluation Of A Hybrid Remote Sensing Evapotranspiration Model For Variable Rate Irrigation Management, J. Burdette Barker, Christopher M. U. Neale, Derek M. Heeren

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Accurate generation of spatial irrigation prescriptions is essential for implementation and evaluation of variable rate irrigation (VRI) technology. A hybrid remote sensing evapotranspiration (ET) model was evaluated for use in developing irrigation prescriptions for a VRI center pivot. The model is a combination of a two-source energy balance model and a reflectance based crop coefficient water balance model. Spatial ET and soil water depletion were modeled for a 10 km² area consisting of rainfed and irrigated maize fields in eastern Nebraska for 2013. Multispectral images from Landsat 8 Operational Land Imager and Thermal Infrared Sensor were used as model …

Review Of Robotic Technology For Strawberry Production, S. G. Defterli, Yeyin Shi, Yunjun Xu

Department of Agricultural and Biological Systems Engineering: Faculty Publications

With an increasing world population in need of food and a limited amount of land for cultivation, higher efficiency in agricultural production, especially fruits and vegetables, is increasingly required. The success of agricultural production in the marketplace depends on its quality and cost. The cost of labor for crop production, harvesting, and post-harvesting operations is a major portion of the overall production cost, especially for specialty crops such as strawberry. As a result, a multitude of automation technologies involving semi-autonomous and autonomous robots have been utilized, with an aim of minimizing labor costs and operation time to achieve a considerable …

Quantification Of Variable Rate Irrigation Benefits And Spatial Variability In Root Zone Water Holding Capacity, Tsz Him Lo

Department of Agricultural and Biological Systems Engineering: Dissertations, Theses, and Student Research

Variable rate irrigation (VRI) investment decisions require field-specific knowledge of benefits. The objective of this research was to help producers and consultants consider and quantify potential benefits of VRI. First, a conceptual model was developed for evaluating the public and/or private gain from adopting VRI where irrigation water supply is non-restrictive. Potential benefits were classified into three categories and were attributed to ten reasons. In the Central Plains at current prices, a small improvement in corn (maize) yield would make a large contribution to VRI profitability. Second, the potential irrigation withdrawal reduction from adapting VRI to spatial heterogeneity of root …

Detecting Grain Flow Rate Using A Laser Scanner, Hossein Navid, Randal K. Taylor, Arzu Yazgi, Ning Wang, Yeyin Shi, Paul Weckler

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Detecting and measuring agricultural material flow is important in a wide range of applications in agricultural engineering, such as material handling, food processing, yield monitoring, and fertilizer spreading. In these applications, flow rate is determined by measuring material mass or volume as a function of time. Although different materials require detection, the methods for a given material type (e.g., granular) can be similar. Researchers have developed methods such as impact based sensors, radiometric-based sensors, and optical methods to detect and measure material flow. Abdul Rahim and Green (1998) studied an optical-fiber sensor (containing 32 light sources and 32 light detectors) …

Computer Vision System For Grading Mangos In Bangladesh, Md Abdul Momin, Md Towfiqur Rahman, Mst Sabrina Sultana, Igathinathane Cannayen

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Mango (Mangifera indica) is one of the most common, important, and popular fruits among fruits produced in Bangladesh. In Bangladesh, mango was cultivated in about 0.078 million acres with an annual production of 0.8 million tonne. However, the technologies used in post-harvest processing (e.g., grading, sorting, etc.) of mango are mostly traditional involving human labors; and the methods are far from satisfactory, in terms of accuracy and throughput. In order to grade mango according to size, we developed a machine vision system with image processing capabilities that can measure sizes of mango fruits from the images. In this system images …

Using Swat To Simulate Crop Yields And Salinity Levels In The North Fork River Basin, Usa, Aaron R. Mittelstet, Daniel E. Storm, Art L. Stoecker

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Crop yields and salinity levels in the North Fork of the Red River (North Fork River) basin, located in southwestern Oklahoma and the Texas Panhandle, were analyzed based on the diverse climate in the region. Saline irrigation water is a major problem in the basin. The Elm Fork Creek flows through salt deposits, making the creek and its receiving stream, the North Fork River, too saline to use for irrigation. This greatly reduces the number of hectares that can be utilized for agricultural crops within the basin. A baseline SWAT model was setup, calibrated and validated to simulate streamflow and …

Ensc 300 (Energy Seminar) Annotated Bibliography, Supplementary Reading, Adam Liska

Adam Liska Papers

Innovation
Sociology of Innovation, Business, & Work
Sustainable Business Strategy
Leadership
Science, Engineering, & Business History
Economics
Energy, Business, & Environmental Policy
Climate Change & Insurance
Education
Ethics

62 monographic resources

Use Of Precisely Sculptured Thin Film (Stf) Substrates With Generalized Ellipsometry To Determine Spatial Distribution Of Adsorbed Fibronectin To Nanostructured Columnar Topographies And Effect On Cell Adhesion, Tadas Kasputis, Alex Pieper, Keith Brian Rodenhausen, Daniel Schmidt, Derek Sekora, Charles Rice, Eva Schubert, Mathias Schubert, Angela K. Pannier

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Sculptured thin film (STF) substrates consist of nanocolumns with precise orientation, intercolumnar spacing, and optical anisotropy, which can be used as model biomaterial substrates to study the effect of homogenous nanotopographies on the three-dimensional distribution of adsorbed proteins. Generalized ellipsometry was used to discriminate between the distributions of adsorbed FN either on top of or within the intercolumnar void spaces of STFs, afforded by the optical properties of these precisely crafted substrates. Generalized ellipsometry indicated that STFs with vertical nanocolumns enhanced total FN adsorption two-fold relative to flat control substrates and the FN adsorption studies demonstrate different STF characteristics influence …

Development And Application Of Quantitative Methods For Ecosystem Services, Rebecca A. Logsdon

Open Access Dissertations

Ecosystem services are benefits that people receive from the environment. Despite recent exponential increases in ecosystem service research, the ecosystem service framework has made little impact on policy and land management decisions, especially in the United States. Two of the main limitations for a lack of ecosystem service considerations in both policy and land management decisions are a need for more advanced quantification methods and the lack of engagement of key stakeholders who are responsible for making land management decisions. This research seeks to address these two limitations by testing and improving quantification methods of ecosystem services and by evaluating …

Heterogeneity Of Infiltration Rates In Alluvial Floodplains As Measured With A Berm Infiltration Technique, Derek M. Heeren, Garey A. Fox, Daniel E. Storm

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Hydrologic heterogeneities (e.g., macropores and gravel outcrops) in floodplains are hypothesized to play an integral role in impacting flow and leaching between the soil surface and shallow alluvial aquifers, which are intricately connected to streams. Infiltration is often assumed to be uniform, but this neglects the spatial variability common in anisotropic, heterogeneous alluvial floodplain soils. The objective of this research was to quantify infiltration and hydraulic conductivity across a range of scales (point to 100 m²) using a berm infiltration technique. Plot-scale leaching experiments were performed across a range of soil types at each of three floodplain sites …

Drip Hydraulics Program, Garret Blocher

BioResource and Agricultural Engineering

This senior project report lays out the production of drip hydraulics software composed in Microsoft Excel and backed by coding in Visual Basic for Applications. The program performs 2 main functions useful in the design of irrigation systems. The first is based on performing single hose computations under three different circumstances. It can solve for the average emitter flow rate given the hose inlet pressure, the inlet pressure given the average emitter flow rate, and can model hose pressures and flow rates while flushing. The second function is to place a manifold in the hydraulically optimum location on a slope. …

Improvement Of Simulating Bmps And Lid Practices In L-Thia-Lid Model, Yaoze Liu

Open Access Dissertations

Best management practices (BMPs) and low impact development (LID) practices are popular approaches used to reduce the negative impacts of urbanization on hydrology and water quality. To assist planners and decision-makers in urban development projects, user-friendly tools are needed to assess the effectiveness of BMPs and LID practices on water quantity and quality. To address this need, the Long-Term Hydrologic Impact Assessment-LID (L-THIA-LID) model was enhanced with additional commonly used BMPs and LID practices represented in the model, improved approaches to estimate hydrology and water quality, and representation of practices in series. The tool was used to evaluate the performance …

Quantiifying Stormwater Runoff Contaminant Mitigation By Bioretention Cells, Patrick J. Walsh

Department of Agricultural and Biological Systems Engineering: Dissertations, Theses, and Student Research

This research study has three objectives, quantify the presence and concentration of selected contaminants in urban stormwater runoff from several urban locations within Lincoln, Nebraska, quantify the effectiveness of two, 10-year old bioretention cells, for reducing concentrations of contaminants in effluent and quantify the effectiveness of six rain gardens.

The primary research sites were two bioretention cells using automated samplers collecting grab samples of stormwater runoff influent and effluent for at least six precipitation events during a two-year period. Additional research sites included samplers for two rainfall, six rain garden, two commercial rooftop, two commercial parking lot, and six residential …

Concomitant Uptake Of Antimicrobials And Salmonella In Soil And Into Lettuce Following Wastewater Irrigation, J. Brett Sallach, Yuping Zhang, Laurie Hodges, Daniel D. Snow, Xu Li, Shannon L. Bartelt-Hunt

Department of Civil and Environmental Engineering: Faculty Publications

The use of wastewater for irrigation may introduce antimicrobials and human pathogens into the food supply through vegetative uptake. The objective of this study was to investigate the uptake of three antimicrobials and Salmonella in two lettuce cultivars. After repeated subirrigation with synthetic wastewater, lettuce leaves and soil were collected at three sequential harvests. The internalization frequency of Salmonella in lettuce was low. A soil horizon-influenced Salmonella concentration gradient was determined with concentrations in bottom soil 2 log CFU/g higher than in top soil. Lincomycin and sulfamethoxazole were recovered from lettuce leaves at concentrations as high as 822 ng/g and …

2015 Nebraska Groundwater Quality Monitoring Report

Nebraska Department of Environmental Quality: Reports

The 2001 Nebraska Legislature passed LB329 (Neb. Rev. Stat. §46-1304) which, in part, directed the Nebraska Department of Environmental Quality (NDEQ) to report on groundwater quality monitoring in Nebraska. Reports have been issued annually since December 2001. The text of the statute applicable to this report follows: “The Department of Environmental Quality shall prepare a report outlining the extent of ground water quality monitoring conducted by natural resources districts during the preceding calendar year. The department shall analyze the data collected for the purpose of determining whether or not ground water quality is degrading or improving and shall present the …

Eight Principles Of Uncertainty For Life Cycle Assessment Of Biofuel Systems, Adam J. Liska

Adam Liska Papers

New environmental regulations in the USA and Europe require a reduction of greenhouse gas (GHG) emissions from transportation fuels as a component of climate change mitigation policy. The US Energy Independence and Security Act of 2007 (EISA) requires GHG emission reductions from the life cycles of biofuels compared to gasoline, by 20% for ethanol from maize grain (maize-ethanol), 60% for cellulosic ethanol, and 50% for other advanced biofuels. To determine these reductions, the US Environmental Protection Agency (EPA) employs life cycle assessment (LCA) methods which were not used previously in national environmental regulations. These regulations, entitled the “Renewable Fuel Standard …

2015 Nebraska Water Monitoring Programs Report, Marty Link, Ryan Chapman

Nebraska Department of Environmental Quality: Reports

The Nebraska Department of Environmental Quality (NDEQ) is charged with monitoring, assessing, and to the extent possible, managing the state’s water resources. The purpose of this work is to protect and maintain high quality water and encourage or execute activities to improve poor water quality. Monitoring is done on nearly 17,000 miles of flowing rivers and streams, more than 134,000 acres of surface water in lakes and reservoirs, as well as the vast storage of groundwater in Nebraska’s aquifers.

Multistage Concentration Of Cenospheres In Fly Ash Using The Inverted Reflux Classifier, A. Kiani, J. Zhou, K.P. Galvin

Coal Combustion and Gasification Products Journal Archive

Cenospheres are one of the most valuable components found in the fly ash waste of coal-fired power stations, consisting of hollow, aluminosilicate spherical shells and offering very low bulk density, high strength, and high thermal resistance. Although wet processing methods offer the best prospect for achieving recovery and concentration of the cenospheres, significant impediments remain for achieving satisfactory economics. This work was concerned with the recovery and concentration of cenospheres from fly ash using a novel system, the inverted reflux classifier (IRC), covering single and multistage processing. The system consists of a series of parallel inclined channels mounted underneath an …

Voc Emissions From Beef Feedlot Pen Surfaces As Affected By Within-Pen Location, Moisture And Temperature, Bryan L. Woodbury, John E. Gilley, David B. Parker, David B. Marx, Roger A. Eigenberg

Department of Statistics: Faculty Publications

A laboratory study was conducted to evaluate the effects of pen location, moisture, and temperature on emissions of volatile organic compounds (VOC) from surface materials obtained from feedlot pens where beef cattle were fed a diet containing 30% wet distillers grain plus solubles. Surface materials were collected from the feed trough (bunk), drainage, and raised areas (mounds) within three feedlot pens. The surface materials were mixed with water to represent dry, wet, or saturated conditions and then incubated at temperatures of 5, 15, 25 and 35 C. A wind tunnel and gas chromatograph-mass spectrometer were used to collect and quantify …

Flow, Spray Pattern, And Droplet Spectra Characteristics Of An Electronically Actuated Variable-Orifice Nozzle, Joe D. Luck, Santosh Pitla, M. P. Sama, S. A. Shearer

Department of Agricultural and Biological Systems Engineering: Faculty Publications

The purpose of this study was to develop and evaluate the flow rate, spray pattern, and droplet spectra characteristics of an actively controlled variable-orifice nozzle at constant carrier pressures. A commercially available variable- orifice nozzle (VariTarget) was modified to allow for direct electromechanical control of the metering stem. The modified system was tested at five carrier pressures ranging from 138 to 414 kPa and five metering stem (and thus orifice) positions. The metering stem position range was chosen because it provided a linear response in flow rate at each carrier pressure. Flow rate testing indicated a turndown ratio of 2.4:1 …

Strengthening Black Cotton Soil With Fly Ash And Moorum: An Investigation Of The Role Of Subgrade And Subbase Layers, Gourav Saxena, Nikhlesh Chaurasia

Coal Combustion and Gasification Products Journal Archive

One of the most effective and economical methods to strengthen clayey soils is addition of stabilizing agents such as fly ash to the soil. In this study, highly plastic clay was stabilized using fly ash. Geotechnical properties such as Atterberg limits, unconfined compressive strength (UCS), and the California bearing ratio (CBR) value of virgin black cotton soil and soil treated with fly ash were evaluated. Soil was stabilized with various proportions of fly ash, i.e., at 0%, 10%, 15%, 20%, and 30%. The UCS of black cotton soil–fly ash mixes is found to be at its maximum at 20% fly …

Using Coal Fly Ash In Agriculture: Combination Of Fly Ash And Poultry Litter As Soil Amendments For Bioenergy Feedstock Production, E. Kudjo Dzantor, Ekundayo Adeleke, Vanaha Kankarla, Oluwatosin Ogunmayowa, Dafeng Hui

Coal Combustion and Gasification Products Journal Archive

Increasing fiscal, human, and environmental costs of coal fly ash (FA) management are leading to advocacy for greater beneficial uses of the by-products as soil amendments in agriculture. Greenhouse experiments were conducted in Armour silt loam (ASL) soil that was amended with FA (10%, wt/wt) with and without poultry litter (PL 5 75 mg N/kg). Biomass productivity of eastern gamagrass (GG), a warm-season perennial grass, was measured to serve as complementary biofuel feedstock to switchgrass (SG). FA was obtained from a site at the 2008 ash spill in Kingston, TN. GG and SG were grown individually in 15-cm-wide 3 41-cm-high …

Sediment Organic Carbon Fate And Transport In A Fluviokarst Watershed In The Bluegrass Region, Admin Husic

Theses and Dissertations--Civil Engineering

Mature karst topography is well recognized within the hydrology and geology communities to include subterranean fluid pathways that act as turbulent conduits conveying fluid from surface stream sinks called swallets to sources called springs. However, we find that little knowledge has been reported with regards to the transport and fate of terrestrially-derived sediment organic carbon (SOC) within karst watersheds. This study investigated the hypothesis that karst pathways could act as biologically active conveyors of SOC that temporarily store sediment, turnover carbon at higher rates than otherwise considered, and recharge depleted SOC back to the surface stream within the fluvial system. …