Bioresource and Agricultural Engineering Commons^™

Synthesis And Characterization Of High-Iron Alite-Calcium Sulfoaluminate-Ferrite Cements Produced From Industrial By-Products, Tristana Y. Duvallet, Youngmin Zhou, Thomas L. Robl, Rodney Andrews

Coal Combustion and Gasification Products Journal Archive

Ordinary Portland cement (OPC) and calcium sulfoaluminate cement (CSAC) are well-known and commonly used construction materials. The clinker phases mainly responsible for their strength development are C3S (alite) in OPC, which hydrates to form a calcium silicate gel phase; and C4A3S ´ (calcium sulfoaluminate) in CSAC, which hydrates to rapidly form ettringite. The purpose of this work was to produce high-iron alite-calcium sulfoaluminate-ferrite cements, by combining C4AF (ferrite), from 5% to 50% by weight, to the C3S and C4A3S ´ clinker phases. Producing this alite-calcium sulfoaluminate-ferrite cement would decrease the requirement of bauxite in the raw materials, which would consequently …

Experimental Tools To Study Molecular Recognition Within The Nanoparticle Corona, Markita P. Landry, Sebastian Kruss, Justin T. Nelson, Gili Bisker, Nicole M. Iverson, Nigel F. Reuel, Michael S. Strano

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Advancements in optical nanosensor development have enabled the design of sensors using synthetic molecular recognition elements through a recently developed method called Corona Phase Molecular Recognition (CoPhMoRe). The synthetic sensors resulting from these design principles are highly selective for specific analytes, and demonstrate remarkable stability for use under a variety of conditions. An essential element of nanosensor development hinges on the ability to understand the interface between nanoparticles and the associated corona phase surrounding the nanosensor, an environment outside of the range of traditional characterization tools, such as NMR. This review discusses the need for new strategies and instrumentation to …

Controlled De-Cross-Linking And Disentanglement Of Feather Keratin For Fiber Preparation Via A Novel Process, Helan Xu, Yiqi Yang

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Pure protein fibers were fabricated from chicken feathers via a potentially green process. In the last several decades, efforts have been made to produce keratin-based industrial products, especially fibers. However, the methods of producing keratin fibers directly from chicken feathers could not be repeated. In this research, protein fibers from chicken feathers were developed using chemicals that could be either derived from renewable resources or facilely recycled. Backbones of keratin were preserved after cleavage of disulfide bonds using cysteine. Sodium dodecyl sulfate (SDS) was applied to dissolve keratin for spinning. Increasing SDS concentration intensified the ordered conformation of keratin, first …

Seed Tape Effects On Corn Emergence Under Greenhouse Conditions, Ramarao Venkatesh, Peter R. Thomison, Colette K. Gabriel, Mark A. Bennett, Elaine M. Grassbaugh, Matthew D. Kleinhenz, Scott A. Shearer, Santosh Pitla

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Seed tape has recently received attention as an alternative planting system for smallholder farmers in underdeveloped regions of South America, Africa, China, and India (Mateus, 2014). Seed companies are also developing seed-tape planting systems for germplasm evaluations (Deppermann et al., 2013). Although seed tape has been promoted as a method for ensuring uniform seed spacing and plant density of small-seeded flowers, herbs, and vegetables (Chancellor, 1969), little or no information is available on the use of seed tape for larger-seeded row crops and its effect on crop emergence. The objective of this study was to compare the emergence of corn …

Experimental And Modelling Evaluation Of Slagging Behaviour Of German Lignite, Martin Kaiser, Alexander Ilyushechkin

Coal Combustion and Gasification Products Journal Archive

The behaviour of mineral matter is important for the characterisation of coal for use in entrained-flow gasification technologies. We investigated four behavioural characteristics—ash fusion temperatures (AFT), slag viscosity versus temperature profiles, temperatures of critical viscosity (TCV), and slag phase compositions—of Rhenish lignite coal ash using laboratory and modelling tools. Our modelling of AFT using coal ash composition provided a wide range of data, with only one (modified) model demonstrating agreement with experimental data. Experimental slag viscosity data were obtained over a temperature range from 1200uC to 1500uC. Where relevant, TCV was also measured. Comparison of these data to the calculated …

The Hydraulic Conductivity Structure Of Gravel-Dominated Vadose Zones Within Alluvial Floodplains, Ronald B. Miller, Derek M. Heeren, Garey A. Fox, Todd Halihan, Daniel E. Storm, Aaron R. Mittelstet

Department of Agricultural and Biological Systems Engineering: Faculty Publications

The floodplains of many gravel-bed streams have a general stratigraphy that consists of a layer of topsoil covering gravel-dominated subsoil. Previous research has demonstrated that this stratigraphy can facilitate preferential groundwater flow through focused linear features, such as paleochannels, or gravelly regions within the vadose zone. These areas within the floodplain vadose zone may provide a route for interactions between the floodplain surface and alluvial groundwater, effectively extending the hyporheic zone across the floodplain during high stream stage. The objective of this research was to assess the structure and scale of texture heterogeneity within the vadose zone within the gravel …

Fly Ash As A Potential Scrubber Of Acidic Wastes From The Phosphate Industries In Israel, Roy Nir Lieberman, Eli Lederman, Ithamar Pelly, Haim Cohen

Coal Combustion and Gasification Products Journal Archive

Fly ash (FA) is produced in Israeli utilities via bituminous coal combustion. It is used as a cement additive or in concrete production, and its economic value is low. The FA produced in Israel is very basic (defined as class F) owing to ambient air quality standards that impose low sulfur content in the imported coals. Because the lime content is high (in the South African coal, ,10 wt%), it is a good potential chemical scrubber to acidic wastes. The phosphate industry in Israel produces mainly phosphate fertilizers and water-treatment products as well as phosphoric acid. The production methods rely …

Geochemistry And Mineralogy Of Coal-Fired Circulating Fluidized Bed Combustion Fly Ashes, Luis F.O. Silva, Marcos L.S. Oliveira, Rubens M. Kautzmann, Claudete G. Ramos, Maria Izquierdo, Shifeng Dai, Jennifer Wilcox, Jeremy Hoffman, James C. Hower

Coal Combustion and Gasification Products Journal Archive

The fuel, bed ash, and fly ash were sampled from a circulating fluidized bed combustion (CFBC) unit at two times. The first sampling was a high-sulfur (S) coal-only run, and the second sampling coincided with an experimental burn of up to 10% switchgrass (Panicum virgatum) pressed pellets mixed with a high-S coal. The latter blend had a higher moisture content and a lower heating value than the coal-only fuel. Given the time between the samplings and the special needs for the experimental run, unavoidable changes in the coal and limestone complicate comparisons of the bed ash and fly ash chemistry …

Design And Construction Of Five Gallon Anaerobic Digesters, Daniel John Schricker

BioResource and Agricultural Engineering

This project discusses the design, construction, and testing of a laboratory scale anaerobic digestion reactors. It included four digesters and two gas measurement devices. The outside dimensions of the digester were 22 inch tall with a 10.5 inch diameter. They were constructed from schedule 40 PVC pipe, with a wall thickness of 0.5 inches. They were designed to be filled with 20 liters of digester feed stock, at a height of 16 inches from the bottom, leaving 5 inches of head space above the digester feed for biogas accumulation. Two of the reactors were heated with Hydrofarm seedling heating pads …

Assessment Of Corn Stover Torrefaction For On-Farm Biochar Production, Christina M. Gerometta

Electronic Theses and Dissertations

Torrefaction is a thermochemical pretreatment process that is typically achieved by slowly heating biomass (<50°C/min) within the temperature range of 200 – 300°C under an inert atmosphere. This process yields a storable solid product with enhanced fuel characteristics that are influenced by the ligno-cellulosic composition of the original feedstock and the imposed torrefaction conditions (time and temperature). This study is an assessment of corn stover properties that are relevant for designing an on-farm torrefaction system. The first portion of this study compared the thermal decomposition behaviors of corn stover fractions (leaf, stalk, cob) to the respective ligno-cellulosic composition using thermo-gravimetric analysis. It was found that the thermal decomposition pattern correlates to the structure and ratio of ligno-cellulosic polymers and provides design guidelines for an on-farm torrefaction system capable of handling large quantities of mixed fraction stover. The second part of this study investigated the effects of torrefaction time and temperature on the mass and energy yield of mixed fraction corn stover using a 46.3 L batch style reactor. It was found that longer reaction times and higher temperatures were required to obtain mass and energy yields similar to those found using lab-scale reactors and finely milled samples. Non-uniform torrefaction occurred between fractions due to chemical composition of each fraction and proximity to the heating elements.

Modeling The H2s Concentrations Affected By Shelterbelts Downwind From A Swine Facility, Brett D. Pettigrew

Electronic Theses and Dissertations

Odor from swine facilities can be a nuisance to the nearby residences and communities. Shelterbelts have been shown to positively impact the downwind air quality, but the impacts are dependent on wind speed and direction, and shelterbelt configuration. The first objective of this research was to develop an empirical model of shelterbelt-induced hydrogen sulfide (H2S) concentration reductions as a function of horizontal distance beyond a swine facility, based on data from a previous study by Hofer (2009). The Hofer (2009) study measured H2S concentrations at a swine facility at four discrete distances beyond the barn (55, 246, 510, and 805 …

Trends In Coal Utilization And Coal Combustion Product Production In Kentucky: Results Of The 2012 Survey Of Power Plants, James C. Hower, Gerald A. Thomas, Shelley G. Hopps

Coal Combustion and Gasification Products Journal Archive

The University of Kentucky Center for Applied Energy Research has conducted a survey of Kentucky’s utility coal-fired power plants every 5 years since 1992. The survey includes a collection of the feed coal and the coal combustion products (CCPs). The latest collection was in 2012, with the accompanying information survey covering trends in 2011. Overall coal-fired energy production decreased, and the nature of the CCPs changed for a number of reasons, including but not limited to, increased gas production in the Appalachians, a series of warm winters, energy conservation, depletion of Appalachian coal reserves, and utility responses to regulations. From …

Pretreatment Of Scenedesmus Sp. Biomass As A Potential Anaerobic Digestion Substrate, Xinyi E, Czarena Crofcheck

Biosystems and Agricultural Engineering Faculty Publications

Algal biomass can be a potential substrate for anaerobic digestion. However, raw algae cells show a resistance to biological degradation, resulting in a slower methane production rate. Varying thermal and chemical pretreatments of algal biomass were investigated in an attempt to increase soluble organic matter (SOM) yield, which would result in enhanced methane production during subsequent anaerobic digestion. Scenedesmus sp. was harvested using three different procedures: with flocculation, with flocculation and drying, and without flocculation or drying. For all pretreatments and algae types, fluorescence micrographs were obtained to visually confirm the degradation of the algal cell walls. A complete 2 …

2014 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.

2014 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 …

Fate Of Antimicrobials And Antimicrobial Resistance Genes In Simulated Swine Manure Storage, Stacey R. Joy, Xu Li, Daniel D. Snow, John Gilley, Bryan L. Woodbury, Shannon L. Bartelt-Hunt

School of Natural Resources: Faculty Publications

The behavior of three antibiotics (bacitracin, chlortetracycline, and tylosin) and two classes of antibiotic resistance genes (ARGs), tet and erm, were monitored in swine manure slurry under anaerobic conditions. First-order decay rates were determined for each antibiotic with half-lives ranging from1 day (chlortetracycline) to 10 days (tylosin). ARGs were monitored in the swine manure slurry, and losses of approximately 1 to 3 orders of magnitude in relative abundance were observed during the 40 day storage period. First-order degradation profiles were observed for chlortetracycline and its corresponding resistance genes, tet(X) and tet(Q). Tylosin was degraded to approximately 10% …

Effects Of Sodium Hydroxide Pretreatment On Structural Components Of Biomass, Alicia A. Modenbach, Sue E. Nokes

Biosystems and Agricultural Engineering Faculty Publications

Pretreatment is a unit operation in the conversion of biomass to valuable products that utilizes various combinations of conditions, including chemicals, heat, pressure, and time, to reduce the recalcitrance of lignocellulose. Many such pretreatments have been developed over the years, as the operating conditions can be adapted so that lignocellulose is modified in ways unique to each pretreatment. By tailoring pretreatment conditions to achieve these modifications, the types of final products produced can be controlled. The purpose of this review is to provide a consolidated source of information for sodium hydroxide effects on lignocellulose. The structural characteristics of lignocellulose and …

Evaluating Sampling Strategies For Rainfall Simulation Studies And Surface Transport Of Antibiotics From Swine Manure Applied To Fescue Plots, Holly K. Enlow

Theses and Dissertations--Biosystems and Agricultural Engineering

Antibiotics are commonly used in animal agriculture to treat and prevent diseases and promote growth. Unfortunately, large amounts of antibiotics are not metabolized, but instead are excreted in urine and feces. Rainfall simulation studies were used to investigate the transport of the antibiotic oxytetracycline and various constituents in runoff and the ability of alum to reduce pollutant transport. Runoff samples were collected at several points during the simulated storm event from each of four treatments: control (C), manure only (M), manure and antibiotics (MA), and manure, antibiotics and alum (MAA). Flow-weighted composite samples were created and compared to the flow …

Sequential Co-Culture Of Anaerobic Bacteria On Switchgrass In A Continuous Flow-Through Reactor For Biofuel Production, Noelia M. Elia

Theses and Dissertations--Biosystems and Agricultural Engineering

Solid substrate cultivation (SSC) using lignocellulosic non-food feedstock, such as switchgrass, is an alternative for advanced biofuel production. Acetone-Butanol-Ethanol (ABE) fermentation in two stages using a sequential culture of microorganisms from the class Clostridia is an approach proposed to increase the butanol production.

The goal was to test the efficacy of a sequential culture on high solid substrate cultivation in batch and continuous cultivation, and to evaluate conditions to optimize butanol production using switchgrass as substrate.

Initial batch experiments were used to determine particle size effect, choice of solvent producer and pretreatment evaluation: The effect of particle size on gas …

Low Cost Flow Sensing For Field Sprayers, Yue Zhang

Theses and Dissertations--Biosystems and Agricultural Engineering

Precisely measuring the flow rate in sprayers is a key technology to precision agriculture. With the development of advanced technologies, the demand for the ability to measure flow rate of individual nozzle has become more important and urgent.

This paper investigates the possibility of developing a low-cost flow rate measurement technique. The technique is based on analyzing the acoustic signal from a microphone placed near the nozzle tip. A comparison between acoustic signal and vibration signal was made to study the relations between them. Then several possible locations of the microphone for measuring flow rate were tested and compared, and …