Bioresource and Agricultural Engineering Commons^™

Solubility Of Fe2(Oh)3cl (Pure-Iron End-Member Of Hibbingite) In Nacl And Na2so4 Brines, Martin Nemer, Yongliang Xiong, Ahmed Ismail, Je-Hun Jang

United States Department of Energy: Publications

Pure-iron end-member hibbingite, Fe₂(OH)₃Cl(s), may be important to geological repositories in salt formations, as it may be a dominant corrosion product of steel waste canisters in an anoxic environment in Na–Cl- and Na–Mg–Cl-dominated brines. In this study, the solubility of Fe₂(OH)₃Cl(s), the pure-iron endmember of hibbingite (Fe^II, Mg)₂(OH)₃Cl(s), and Fe(OH)₂(s) in 0.04 m to 6 m NaCl brines has been determined. For the reaction

Fe₂ (OH)₃Cl(s) + 3H⁺↔ 3H₂O + 2Fe²⁺ + Cl⁻,

the …

Nonlocal Instability Analysis Of Fcc Bulk And (100) Surfaces Under Uniaxial Stretching, Geng Yun, Penghui Cao, Jonathan Zimmerman, Terry Delph, Harold Park

United States Department of Energy: Publications

The objective of this paper is to examine the instability characteristics of both a bulk FCC crystal and a (100) surface of an FCC crystal under uniaxial stretching along a h100i direction using an atomisticbased nonlocal instability criterion. By comparison to benchmark atomistic simulations, we demonstrate that for both the FCC bulk and (100) surface, about 5000–10,000 atoms are required in order to obtain an accurate converged value for the instability strain and a converged instability mode. The instability modes are fundamentally different at the surface as compared to the bulk, but in both cases a strong dependence of the …

Evidence For Multiple Modes Of Uranium Immobilization By An Anaerobic Bacterium, Allison E. Ray, John R. Bargar, Vaideeswaran Sivaswamy, Alice C. Dohnalkova, Yoshiko Fujita, Brent M. Peyton, Timothy S. Magnuson

United States Department of Energy: Publications

Microbial reduction of hexavalent uranium has been studied widely for its potential role in bioremediation and immobilization of soluble U(VI) in contaminated groundwater. More recently, some microorganisms have been examined for their role in immobilization of U(VI) via precipitation of uranyl phosphate minerals mediated by microbial phosphate release, alleviating the requirement for long-term redox control. Here, we investigated the mechanism of U(VI) removal mediated by an environmental isolate, strain UFO1, that is indigenous to the Field Research Center (FRC) in Oak Ridge, TN and has been detected in U(VI)- contaminated sediments. Changes in U(VI) speciation were examined in the presence …

Quantifying Differences In The Impact Of Variable Chemistry On Equilibrium Uranium(Vi) Adsorption Properties Of Aquifer Sediments, Deborah Stoliker, Douglas Kent, John M. Zachara

United States Department of Energy: Publications

Uranium adsorption − desorption on sediment samples collected from the Hanford 300-Area, Richland, WA varied extensively over a range of field-relevant chemical conditions, complicating assessment of possible differences in equilibrium adsorption properties. Adsorption equilibrium was achieved in 500−1000 h although dissolved uranium concentrations increased over thousands of hours owing to changes in aqueous chemical composition driven by sediment-water reactions. A nonelectrostatic surface complexation reaction, >SOH + UO₂²⁺ + 2CO₃^2- = >SOUO₂(CO₃HCO₃)^2- , provided the best fit to experimental data for each sediment sample resulting in a range of conditional …

River-Induced Flow Dynamics In Long-Screen Wells And Impact On Aqueous Samples, Vince R. Vermeul, James Mckinley, Darrell R. Newcomer, Robert D. Mackley, John M. Zachara

United States Department of Energy: Publications

Previously published field investigations and modeling studies have demonstrated the potential for sample bias associated with vertical wellbore flow in conventional monitoring wells constructed with long-screened intervals. This article builds on the existing body of literature by (1) demonstrating the utility of continuous (i.e., hourly measurements for ∼1 month) ambient wellbore flow monitoring and (2) presenting results from a field experiment where relatively large wellbore flows (up to 4 L/min) were induced by aquifer hydrodynamics associated with a fluctuating river boundary located approximately 250 m from the test well. The observed vertical wellbore flows were strongly correlated with fluctuations in …

Genome Sequence Of Victivallis Vadensis Atcc Baa-548, An Anaerobic Bacterium From The Phylum Lentisphaerae, Isolated From The Human Gastrointestinal Tract, Mark W. J. Van Passel, Ravi Kant, Airi Palva, Susan Lucas, Alex Copeland, Alla Lapidus, Tijana Glavina Del Rio, Eileen Dalin, Hope Tice, David Bruce, Lynne Goodwin, Sam Pitluck, Karen Walston Davenport, David Sims, Thomas Brettin, John Detter, Shunsheng Han, Frank Larimer, Miriam Land, Loren Hauser, Nikos C. Kyrpides, Galina Ovchinnikova, P. Paul Richardson, Willem M. De Vos, Hauke Smidt, Erwin G. Zoetendal

United States Department of Energy: Publications

Victivallis vadensis ATCC BAA-548 represents the first cultured representative from the novel phylum Lentisphaerae, a deep-branching bacterial lineage. Few cultured bacteria from this phylum are known, and V. vadensis therefore represents an important organism for evolutionary studies. V. vadensis is a strictly anaerobic sugar-fermenting isolate from the human gastrointestinal tract.

Evaluation Of Select Sensors For Real-Time Monitoring Of Escherichia Coli In Water Distribution Systems, Syreeta L. Miles, Ryan G. Sinclair, Mark R. Riley, Ian L. Pepper

Department of Agricultural and Biological Systems Engineering: Faculty Publications

This study evaluated real-time sensing of Escherichia coli as a microbial contaminant in water distribution systems. Most sensors responded to increased E. coli concentrations, showing that select sensors can detect microbial water quality changes and be utilized as part of a contaminant warning system.

Improved Soil Mixing And Delivery System For A Storm Runoff Simulator, William C. Alms, Thomas G. Franti, David P. Shelton

Department of Agricultural and Biological Systems Engineering: Faculty Publications

An earlier version of a storm runoff simulator to test conservation buffers reproduced target hydrographs and sedigraphs using uniform, fine sand; however, it was unable to uniformly mix and deliver native sediment. The objectives of this work reported were to create a method to process native agricultural sediment, mix a uniform sediment slurry at a target concentration, and create a control system that will deliver the slurry in varying flow rates corresponding to a target sedigraph. Eroded silty clay (14% sand) was scraped, dried, and processed with a hammer mill. A sand (93% sand) and loam (44% sand) were dried …

Irrigation Efficiency And Uniformity, And Crop Water Use Efficiency, Suat Irmak, Lameck O. Odhiambo, William L. Kranz, Dean E. Eisenhauer

Department of Agricultural and Biological Systems Engineering: Faculty Publications

This Extension Circular describes various irrigation efficiency, crop water use efficiency, and irrigation uniformity evaluation terms that are relevant to irrigation systems and management practices currently used in Nebraska, in other states, and around the world. The definitions and equations described can be used by crop consultants, irrigation district personnel, and university, state, and federal agency personnel to evaluate how efficiently irrigation water is applied and/or used by the crop, and can help to promote better or improved use of water resources in agriculture.

As available water resources become scarcer, more emphasis is given to efficient use of irrigation water …

A Case Study Concerning The Effects Of Controller Response And Turning Movements On Application Rate Uniformity With A Self-Propelled Sprayer, Joe D. Luck, A. Sharda, Santosh Pitla, J. P. Fulton, S. A. Shearer

Department of Agricultural and Biological Systems Engineering: Faculty Publications

The use of precision agriculture technologies such as automatic boom section control allows producers to reduce off-target application when applying herbicides. While automatic boom section control provides benefits, pressure differences across the spray boom resulting from boom section actuation may lead to off-rate application errors. Off-rate errors may also result from spray rate controller compensation for ground speed changes or velocity variation across the spray boom during turning movements. This project focused on characterizing application rate variation for three fields located in central Kentucky. GPS coordinates, boom control status, and nozzle pressure data (at 15 nozzle locations) were recorded as …

Development Of An Integrated Soil Properties Mapping System, Rajveer S. Dhillon

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

One of the main goals of precision agriculture (PA) is to define spatial variability in soil properties within an agricultural field to make decisions that can maximize profitability and reduce negative environmental impact. Various soil sensor systems have been developed over the years to map soil properties on-the-go. In this study, an Integrated Soil Mapping System (ISMS) was developed to predict soil water content, soil organic matter, and soil mechanical resistance on-the-go using a capacitance moisture sensor, an optical sensor, and a load cell sensor respectively. These sensors were mounted on the ISMS for acquiring three different data layers at …

Comparison Of Subsurface And Surface Runoff Phosphorus Transport Capacities In Alluvial Floodplains, Aaron R. Mittelstet, Derek M. Heeren, Daniel E. Storm, Garey A. Fox, M. J. White, R. B. Miller

Department of Agricultural and Biological Systems Engineering: Faculty Publications

There have been numerous studies on phosphorus (P) contributions from surface runoff, but studies comparing the contribution of surface versus subsurface P are limited, as subsurface transport is often considered negligible. Previous work has shown that the transport of P in the gravelly subsurface at two sites in northeast Oklahoma can be significant, especially in preferential flow paths (PFPs), hypothesized to be buried gravel bars. The objective of this project was to quantify subsurface P losses based on field data, and compare with surface runoff P losses derived from Pasture Phosphorus Management Calculator (PPM Plus) simulations. Ozark ecoregion study sites …

Nutrient Transport In Runoff As Affected By Diet, Tillage, And Manure Application Rate, John E. Gilley, Lisa M. Durso, R.A. Eigenberg, David B. Marx, Brian L. Woodbury

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Feedlot operators may increase profitability by including distillers grains in finishing diets. However, the nutrients remaining in the by‐product are concentrated by about a factor of three during the distillation process. Manure can be applied to meet single‐ or multiple‐year crop nutrient requirements. The water quality effects of the use of distillers grains in feedlot diets and multiple‐year manure application have not been well quantified. The objectives of this study were to (1) compare the runoff water quality effects resulting from the application of manure derived from corn and distillers grain diets, (2) examine the effects of till and no‐till …

Enhanced Anthocyanin Extraction From Red Cabbage Using Pulsed Electric Field Processing, Tanya K. Gachovska, David A. Cassada, Jeyamkondan Subbiah, Milford Hanna, Harshavardhan Thippareddi, Daniel D. Snow

Department of Agricultural and Biological Systems Engineering: Faculty Publications

This study was conducted to evaluate the effect of pulsed electric field (PEF) treatment on anthocyanin extraction from red cabbage using water as a solvent. Mashed cabbage was placed in a batch treatment chamber and subjected to PEF (2.5 kV/cm electric field strength; 15 μs pulse width and 50 pulses, specific energy 15.63 J/g). Extracted anthocyanin concentrations (16 to 889 μg/mL) were determined using HPLC. Heat and light stabilities of the control and PEF-treated samples, having approximately the same initial concentrations, were studied. PEF treatments enhanced total anthocyanin extraction in water from red cabbage by 2.15 times with a higher …

Multi-Robot System Control Architecture (Mrsca) For Agricultural Production, Santosh Pitla, Joe D. Luck, Scott A. Shearer

Department of Agricultural and Biological Systems Engineering: Presentations and White Papers

Coordinating multiple autonomous robots for achieving an assigned collective task presents a complex engineering challenge. In this paper multi robot system control architecture (MRSCA) for the coordination of multiple agricultural robots is developed. The two important aspects of MRSCA; coordination strategy and inter-robot communication were discussed with typical agricultural tasks as examples. Classification of MRS into homogeneous and heterogeneous robots was done to identify appropriate form of cooperative behavior and inter-robot communication. The framework developed, proposes that inter-robot communication is not always required for a MRS. Three types of cooperative behaviors; No-cooperation, modest cooperation and absolute cooperation for a MRS …

Impact Of Preferential Flow Paths On Alluvial Groundwater Flow Patterns And Phosphorus Transport, Derek M. Heeren, Ronald B. Miller, Garey A. Fox, Daniel E. Storm, Aaron R. Mittelstet, Chad J. Penn

Department of Agricultural and Biological Systems Engineering: Faculty Publications

While surface runoff is considered to be the primary transport mechanism for phosphorus (P), subsurface transport through coarse subsoil to gravel bed streams may be significant and represent a source of P not alleviated by current conservation practices (e.g., riparian buffers). Previous research has documented P transport in a preferential flow path (PFP) identified as a buried gravel bar. It is hypothesized that PFPs, if connected to the soil surface, provide a rapid and efficient method of transporting P, and that these alluvial features are transient storage zones for nutrients, acting as a sink during high flow and a source …

Geophysical Mapping Of Preferential Flow Paths Across Multiple Floodplains, Ronald B. Miller, Derek M. Heeren, Garey A. Fox, Daniel E. Storm, Todd Halihan, Aaron R. Mittelstet

Department of Agricultural and Biological Systems Engineering: Faculty Publications

In the Ozark ecoregion of Oklahoma, Arkansas and Missouri, the erosion of carbonate bedrock (primarily limestone) by slightly acidic water has left a residuum of chert gravel, producing gravel-bed streams and floodplains generally consisting of coarse chert gravel overlain by a mantle (1 to 300 cm) of gravelly loam or silt loam. Previous research has documented the occurrence of preferential flow paths (PFP) in an alluvial floodplain hypothesized to be a buried gravel bar. Field experiments have shown that the PFP affected alluvial groundwater flow in the floodplain and that water flow in the PFP was transmitted at rates that …

Pneumatic Control Of A Variable Orifice Nozzle, Joe D. Luck, Michael P. Sama, Santosh Pitla, Scott A. Shearer

Department of Agricultural and Biological Systems Engineering: Presentations and White Papers

A variable-orifice nozzle with droplet optimization was recently developed and introduced for use on agricultural sprayers. The VariTarget (VT) nozzle reacts to changes in the system flow rate via a metering assembly that is controlled by a diaphragm and spring. As the liquid pressure changes, the VT metering assembly attempts to control the flow rate and spray pattern exiting the nozzle. The goal of this study was to replace the spring controlled “reactive” system with a pneumatically controlled metering assembly. The proposed system would allow for the metering assembly to adjust the flow rate and spray pattern exiting the nozzle …

Optimization And Economic Evaluation Of Industrial Gas Production And Combined Heat And Power Generation From Gasification Of Corn Stover And Distillers Grains, Ajay Kumar, Yaşar Demirel, David D. Jones, Milford Hanna

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Thermochemical gasification is one of the most promising technologies for converting biomass into power, fuels and chemicals. The objectives of this study were to maximize the net energy efficiency for biomass gasification, and to estimate the cost of producing industrial gas and combined heat and power (CHP) at a feedrate of 2,000 kg/h. Aspen Plusbased model for gasification was combined with a CHP generation model, and optimized using corn stover and dried distillers grains with solubles (DDGS) as the biomass feedstocks. The cold gas efficiencies for gas production were 57% and 52%, respectively, for corn stover and DDGS. The selling …

Nutrient Transport In Runoff From Feedlots As Affected By Wet Distillers Grain Diet, John E. Gilley, Jason R. Vogel, Roger A. Eigenberg, David B. Marx, Brian L. Woodbury

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Distillers byproducts can serve as valuable sources of protein and energy for beef cattle. However, the water quality effects of the use of distillers byproducts in cattle rations are not well understood. The objectives of this study were to: (1) measure soil properties and nutrient transport in runoff from feedlot surfaces as affected by corn‐based and wet distillers grain diets, (2) compare the effects of unconsolidated surface materials and consolidated subsurface materials on feedlot soil characteristics and runoff nutrient transport, (3) determine if runoff nutrient transport from feedlot surfaces is correlated to selected feedlot soil properties, and (4) identify the …

Reducing The Cost Of Pumping Irrigation Water, Derrel L. Martin, William L. Kranz, Tom W. Dorn, Steve R. Melvin, Alan J. Corr

Department of Agricultural and Biological Systems Engineering: Presentations and White Papers

Irrigation accounts for a large portion of the energy used in Nebraska agriculture. The cost to pump irrigation water depends on the type of energy used to power the pumping unit. This document describes a method to estimate the cost of pumping water and to compare the amount of energy used to that for a well maintained and designed pumping plant. The results can help determine the feasibility of repairing the pumping plant.

Updating The Nebraska Pumping Plant Performance Criteria, William Kranz, Derrel L. Martin, Dean Patterson, Jerry Hudgins, Simon Van Donk, C. Dean Yonts

Department of Agricultural and Biological Systems Engineering: Presentations and White Papers

Irrigation water is removed from groundwater storage using deep well turbine pumps powered by electric motors or diesel, gasoline, propane, ethanol, or natural gas internal combustion engines. For best operating efficiency irrigation power units are selected to specifically meet the requirements of the irrigation system that include how deep the water in the well is under pumping conditions, the water pressure required at the pump outlet, and the system flow rate. The evaluation of pumping plants to establish pumping plant performance dates back into the 1950’s when researchers at the University of Nebraska were unable to directly compare the operation …

Cytotoxicity Of Bacterial-Derived Toxins To Immortal Lung Epithelial And Macrophage Cells, Dianne E. Peterson, Jayne M. Collier, Matthew E. Katterman, Rachel A. Turner, Mark R. Riley

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Health risks associated with inhalation and deposition of biological materials have been a topic of great concern due to highly publicized cases of inhalation anthrax, of new regulations on the release of particulate matter, and to increased concerns on the hazards of indoor air pollution. Here, we present an evaluation of the sensitivity of two immortal cell lines (A549, human lung carcinoma epithelia) and NR8383 (rat alveolar macrophages) to a variety of bacterial-derived inhalation hazards and simulants including etoposide, gliotoxin, streptolysin O, and warfarin. The cell response is evaluated through quantification of changes in mitochondrial succinate dehydrogenase activity, release of …

Ellipsometric Study Of Single-Crystal Γ-Inse From 1.5 To 9.2 Ev, S. G. Choi, D. E. Aspnes, A. L. Fuchser, C. Martinez-Tomas, V. Muñoz Sanjosé, D. H. Levi

United States Department of Energy: Publications

We report the component E ┴ c of the pseudodielectric-function tensor <ε(E)> = <ε₁(E)> + i< ε₂(E)> of γ-phase single-crystal InSe, obtained from 1.5 to 9.2 eV by vacuum-ultraviolet spectroscopic ellipsometry with the sample at room temperature. Overlayer artifacts were reduced as far as possible by measuring fresh surfaces prepared by cleavage. Accurate critical-point energies of observed structures were obtained by a combined method of spectral analysis.

Load-Locked Dc High Voltage Gaas Photogun With An Inverted-Geometry Ceramic Insulator, P. A. Adderley, J. Clark, J. Grames, J. Hansknecht, K. Surles-Law, D. Machie, M. Poelker, M. L. Stutzman, R. Suleiman

United States Department of Energy: Publications

A new dc high voltage spin-polarized photoelectron gun has been constructed that employs a compact inverted-geometry ceramic insulator. Photogun performance at 100 kV bias voltage is summarized.

I. INTRODUCTION

All of the nuclear physics experiments conducted at the Continuous Electron Beam Accelerator Facility (CEBAF) at the Thomas Jefferson National Accelerator Facility (Jefferson Lab) receive electron beams from a dc high voltage spin-polarized GaAs photoemission gun. Since 1995, the year the first polarized electron source was installed at CEBAF [1], there have been four different photogun designs with each new gun an improvement over its predecessor. The most recent design employs …

Linearized Theory Of Peridynamic States, S. A. Silling

United States Department of Energy: Publications

A state-based peridynamic material model describes internal forces acting on a point in terms of the collective deformation of all the material within a neighborhood of the point. In this paper, the response of a state-based peridynamic material is investigated for a small deformation superposed on a large deformation. The appropriate notion of a small deformation restricts the relative displacement between points, but it does not involve the deformation gradient (which would be undefined on a crack). The material properties that govern the linearized material response are expressed in terms of a new quantity called the modulus state. This determines …

Nebraska Statewide Wind Integration Study: Executive Summary April 2008 – January 2010, Enernex Corporation Knoxville, Tennessee, Ventyx Atlanta, Georgia, Nebraska Power Association Lincoln, Nebraska

United States Department of Energy: Publications

Wind generation is a source of electric energy that, in sufficient quantity, can cause concern for the operation of the bulk power system because of the variability and uncertainty of the wind. Most short-term planning and operational functions supporting the electric power grid are centered on supply resources that have capacity attributes – i.e. they can be dispatched (controlled up and down) to a specified power level for a specified period of time. The need to maintain very high levels of system reliability reinforces the preference in operations toward resources having capacity attributes. Wind generation usually has relatively low capacity …

Microbial And Mineralogical Characterizations Of Soils Collected From The Deep Biosphere Of The Former Homestake Gold Mine, South Dakota, Gurdeep Rastogi, Shariff Osman, Ravi K. Kukkadapu, Mark Engelhard, Parag A. Vaishampayan, Gary L. Andersen, Rajesh K. Sani

United States Department of Energy: Publications

A microbial census on deep biosphere (1.34 km depth) microbial communities was performed in two soil samples collected from the Ross and number 6Winze sites of the former Homestake gold mine, Lead, South Dakota using high-density 16S microarrays (PhyloChip). Soil mineralogical characterization was carried out using X-ray diffraction, X-ray photoelectron, and Mössbauer spectroscopic techniques which demonstrated silicates and iron minerals (phyllosilicates and clays) in both samples. Microarray data revealed extensive bacterial diversity in soils and detected the largest number of taxa in Proteobacteria phylum followed by Firmicutes and Actinobacteria. The archael communities in the deep gold mine environments were …

Microbial Reduction Of Uranium Under Iron- And Sulfate-Reducing Conditions: Effect Of Amended Goethite On Microbial Community Composition And Dynamics, H.S. Moon, L. Mcguinness, Ravi K. Kukkadapu, A.D. Peacock, John Komlos, L.J. Kerkhof, P.E. Long, Peter R. Jaffe

United States Department of Energy: Publications

There is a growing need for a better understanding of the biogeochemical dynamics involved in microbial U(VI) reduction due to an increasing interest in using biostimulation via electron donor addition as a means to remediate uranium contaminated sites. U (VI) reduction has been observed to be maximized during iron-reducing conditions and to decrease upon commencement of sulfate-reducing conditions. There are many unknowns regarding the impact of iron/sulfate biogeochemistry on U(VI) reduction. This includes Fe(III) availability as well as the microbial community changes, including the activity of iron-reducers during the uranium biostimulation period even after sulfate reduction becomes dominant. Column experiments …

Confinement Resonances In Photoionization Of Xe@C+60, A. L. D. Kilcoyne, A. Aguilar, A. Muller, S. Schippers, C. Cisneros, G. Alna’Washi, N. B. Aryal, K. K. Baral, D. A. Esteves, C. M. Thomas, R. A. Phaneuf

United States Department of Energy: Publications

Experimental evidence is presented for confinement resonances associated with photoabsorption by a Xe atom in a C₆₀ cage. The giant 4d resonance in photoionization of Xe is predicted to be redistributed into four components due to multipath interference of photoelectron waves reflected by the cage. The measurements were made in the photon energy range 60–150 eV by merging a beam of synchrotron radiation with a mass/charge selected Xe@C⁺₆₀ ion beam. The phenomenon was observed in the Xe@C³⁺₅₈ product ion channel.