Bioresource and Agricultural Engineering Commons^™

A Submersible Magnetic Stirrer For Use In Measuring Photosynthesis In A Biofloc Technology Production System, Bartholomew W. Green, E. Gregory O'Neal

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Measuring photosynthesis or primary productivity in biofloc technology production systems is challenging because the biofloc must be maintained in suspension constantly. Photosynthesis can be measured in external incubators designed to keep the biofloc suspended in the biochemical oxygen demand (BOD) bottle, but primary productivity must be measured in the biofloc technology production system culture unit. Therefore, a submersible device is required to keep the biofloc suspended in the BOD bottle. This report details a submersible, air-powered magnetic stirrer that we designed, fabricated from off-the-shelf materials, and tested in biofloc technology production system tanks.

2012 Nebraska Water Monitoring Programs Report, Marty Link, Mike Archer

Nebraska Department of Environmental Quality: Reports

The following Nebraska Department of Environmental Quality staff have contributed to this report with their photos, maps, numbers, words, and editing. Their efforts are greatly appreciated and gratefully acknowledged here: Mike Archer, Ken Bazata, Dave Bubb, Ryan Chapman, Jason Garber, Patrick Hartman, Tom Heatherly, Dave Ihrie, Dan Inman, Greg Michl, Will Myers, Patrick O’Brien (NARD), Brad Routt, and Dave Schumacher.

Sparse Pseudospectral Approximation Method, Paul G. Constantine, Michael Eldred, Eric Phipps

United States Department of Energy: Publications

Multivariate global polynomial approximations – such as polynomial chaos or stochastic collocation methods – are now in widespread use for sensitivity analysis and uncertainty quantification. The pseudospectral variety of these methods uses a numerical integration rule to approximate the Fourier-type coefficients of a truncated expansion in orthogonal polynomials. For problems in more than two or three dimensions, a sparse grid numerical integration rule offers accuracy with a smaller node set compared to tensor product approximation. However, when using a sparse rule to approximately integrate these coefficients, one often finds unacceptable errors in the coefficients associated with higher degree polynomials.

By …

Raman/Rayleigh Scattering And Co-Lif Measurements In Laminar And Turbulent Jet Flames Of Dimethyl Ether, Frederik Fuest, Robert S. Barlow, Jyh-Yuan Chen, Andreas Dreizler

United States Department of Energy: Publications

To reduce the impact of combustion of fossil fuels on air quality and climate change, dimethyl ether (DME) is a promising alternative diesel fuel candidate. Technical combustion processes, including formation of pollutants, are influenced by turbulence–chemistry interaction. Therefore, accurate prediction by computational combustion models of combustion systems burning DME must account for multiple scalars and scalar gradients. The testing of such models requires detailed experiments. Here a study is presented on the feasibility of simultaneous species and temperature measurements in turbulent dimethyl ether flames, using line-imaged Raman/Rayleigh scattering of the major species H₂, O₂, N_{2 …}

Application Of Pdf Mixing Models To Premixed Flames With Differential Diffusion, Edward Richardson, Jacqueline Chen

United States Department of Energy: Publications

Differential diffusion alters the balance of reaction and diffusion in turbulent premixed combustion, affecting the performance and emissions of combustion devices. Modelling combustion devices with Probability or Filtered Density Function (PDF or FDF) methods provides an exact treatment for the change in composition due to chemical reaction, while molecular mixing has to be modelled. Previous PDF molecular mixing models do not account for differential diffusion in a manner which satisfies realizability requirements. A new approach for treating differential diffusion, which ensures realizability, is proposed for pairwise-exchange mixing models in general, and applied in the Interaction by Exchange with the Mean …

Pore-Scale Characterization Of Biogeochemical Controls On Iron And Uranium Speciation Under Flow Conditions, Carolyn I. Pearce, Michael J. Wilkins, Changyong Zhang, Steve M. Heald, James K. Fredrickson, John M. Zachara

United States Department of Energy: Publications

Etched silicon microfluidic pore network models (micromodels) with controlled chemical and redox gradients, mineralogy, and microbiology under continuous flow conditions are used for the incremental development of complex microenvironments that simulate subsurface conditions. We demonstrate the colonization of micromodel pore spaces by an anaerobic Fe(III)-reducing bacterial species (Geobacter sulfurreducens) and the enzymatic reduction of a bioavailable Fe(III) phase within this environment. Using both Xray microprobe and X-ray absorption spectroscopy, we investigate the combined effects of the precipitated Fe(III) phases and the microbial population on uranium biogeochemistry under flow conditions. Precipitated Fe(III) phases within the micromodel were most effectively …

Quantitative 3-D Elemental Mapping By La-Icp-Ms Of A Basaltic Clast From The Hanford 300 Area, Washington, Usa, Sheng Peng, Qinhong Hu, Robert Ewing, Chongxuan Liu, John M. Zachara

United States Department of Energy: Publications

Laser ablation with inductively coupled plasma-mass spectrometry (LA-ICP-MS) was used to measure elemental concentrations at the 100-μm scale in a 3-dimensional manner within a basaltic clast sample collected from the Hanford 300 Area in south-central Washington State, United States. A calibration method was developed to quantify the LAICP- MS signal response using a constant-sum mass fraction of eight major elements; the method produced reasonable concentration measurements for both major and trace elements when compared to a standard basalt sample with known concentrations. 3-Dimensional maps (stacked 2-D contour layers, each representing 2100 μm × 2100 μm) show …

Molecular Underpinnings Of Fe(Iii) Oxide Reduction By Shewanella Oneidensis Mr-1, Liang Shi, Kevin Rosso, Tomas Clarke, David Richardson, John M. Zachara, James K. Fredrickson

United States Department of Energy: Publications

In the absence of O₂ and other electron acceptors, the Gram-negative bacterium Shewanella oneidensis MR-1 can use ferric [Fe(III)] (oxy) (hydr) oxideminerals as the terminal electron acceptors for an aerobic respiration. At circumneutral pH and in the absence of strong complexing ligands, Fe(III) oxides are relatively insoluble and thus are external to the bacterial cells. S. oneidensis MR-1 and related strains of metal-reducing Shewanella have evolved machinery (i.e.,metal-reducing or Mtr pathway) for transferring electrons from the inner-membrane, through the periplasmanda cross the outer-membrane to the surface of extracellular Fe(III) oxides. The protein components identified to date for the Mtr …

The ‘Porin–Cytochrome’ Model For Microbe-To-Mineral Electron Transfer, David Richardson, Julea Butt, James K. Fredrickson, John M. Zachara, Liang Shi, Marcus Edwards, Gaye White, Nanakow Baiden, Andrew Gates, Sophie Marritt, Thomas Clarke

United States Department of Energy: Publications

Many species of bacteria can couple anaerobic growth to the respiratory reduction of insoluble minerals containing Fe(III) or Mn(III/IV). It has been suggested that in Shewanella species electrons cross the outer membrane to extracellular substrates via ‘porin–cytochrome’ electron transport modules. The molecular structure of an outer-membrane extracellular-facing deca-haem terminus for such a module has recently been resolved. It is debated how, once outside the cells, electrons are transferred from outer-membrane cytochromes to insoluble electron sinks. This may occur directly or by assemblies of cytochromes, perhaps functioning as ‘nanowires’, or via electron shuttles. Here we review recent work in this field …

Evaluation Of A Rhodamine-Wt Dye/Glycerin Mixture As A Tracer For Testing Direct Injection Systems For Agricultural Sprayers, Joe D. Luck, Scott A. Shearer, Brian D. Luck, Fred A. Payne

Department of Agricultural and Biological Systems Engineering: Faculty Publications

The purpose of this study was to provide valuable insight regarding the use of Rhodamine WT (red) dye as a tracer for evaluating injected concentrations. More specifically, the effects of mixing the dye with glycerin to simulate the viscosity of a pesticide (e.g., glyphosate) or injecting the dye/glycerin mixture into deionized (DI) versus tap water on developing appropriate calibration equations were evaluated. Test results indicated that mixing the dye in a solution of glycerin and DI water significantly affected absorbance measurements compared to the dye mixed solely in DI water. The error in estimating absorbance was 7.4% between the two …

Fabrication And Characterization Of Dna-Loaded Zein Nanospheres, Mary C. Regier, Jessica D. Taylor, Tyler Borcyk, Yiqi Yang, Angela K. Pannier

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Background: Particulates incorporating DNA are promising vehicles for gene delivery, with the ability to protect DNA and provide for controlled, localized, and sustained release and transfection. Zein, a hydrophobic protein from corn, is biocompatible and has properties that make it a promising candidate material for particulate delivery, including its ability to form nanospheres through coacervation and its insolubility under physiological conditions, making it capable of sustained release of encapsulated compounds. Due to the promise of this natural biomaterial for drug delivery, the objective of this study was to formulate zein nanospheres encapsulating DNA as the therapeutic compound, and to …

Assessment Of Conductivity Sensors Performance For Monitoring Mined Land Discharged Waters And An Evaluation Of The Hydrologic Performance Of The Guy Cove Stream Restoration Project, Travis Pritchard Maupin

Theses and Dissertations--Biosystems and Agricultural Engineering

The surface mining method of mountaintop removal has been shown to adversely affect the water quality and hydrologic characteristics of downstream regions. Based on recent scientific literature, the U.S. EPA issued guidance on the specific conductivity (EC25ºC) of waters discharged from mined lands in the Appalachian Coal Belt Region stating that these waters should have an EC25ºC less than 300-500 μS cm-1. Hence, accurately measuring EC25ºC levels of mine discharged waters has significant implications. Furthermore, the development of reclamation techniques that positively impact the hydrological and water quality aspects of valley fill (VF) discharge is needed. To tackle these questions, …

Evaluation Of Transitions For Testing Agricultural Ventilation Fans With The Fan Assessment Numeration System (Fans), Igor Moreira Lopes

Theses and Dissertations--Biosystems and Agricultural Engineering

The Fan Assessment Numeration System (FANS) is an improved air velocity traverse method for measuring in situ fan performance. The FANS has been widely used, but variations of its test procedure are commonly employed to accommodate physical or operational barriers encountered in the field. This laboratory study evaluated the use of transitions to connect a 1.37m FANS unit to two smaller fans (1.22m and 0.91m diameter) and one 1.37m diameter fan. Tests were conducted with the FANS unit positioned on both intake and discharge sides of the fans. Three different transition angles (30^o, 45^o and 60^{o …}

Development Of A Noncontact Sensor For Monitoring Milk Coagulation And Cutting Time Prediction In Cheese Making, Molly D. Craft-Jenkins

Theses and Dissertations--Biosystems and Agricultural Engineering

Cheese products are manufactured more consistently and with better quality if the curd cutting time can be consistently selected. An optical sensor that accurately predicts cutting time has been developed for large cheese vats, but the initial cost of these sensors makes them uneconomical for small artisan cheese manufacturers. The small artisan cheese vats require an inexpensive sensor technology that can be implemented simply. The initial cost of purchasing a sensor and installing these sensors plus the need for a computational program for implementing the algorithm make this technology excessively expensive for these smaller cheese manufacturers. The objective of this …

Evaluation Of Separation Method Additives For The Recovery Of Bacteria From Food Matrices, Jennifer Leanne Frederick

Theses and Dissertations--Biosystems and Agricultural Engineering

The microbiological testing of foods is a well-established science. Due to the severity of foodborne pathogen illnesses, the widespread use and implementation of rapid detection methods in food testing labs is increasingly important. The first step for successful testing is sampling. Surfactants have been highly used in food microbiology, but there is not much, if any, published research about the use of fatty alcohols and chemical dispersants as aids in microbial separation. The microbial extraction efficiency of Escherichia coli K12 and Listeria innocua from hot dogs, spinach, and milk was measured using chemical additives (surfactants, fatty alcohols, and a chemical …

Computational Tools For Improving Route Planning In Agricultural Field Operations, Rodrigo S. Zandonadi

Theses and Dissertations--Biosystems and Agricultural Engineering

In farming operation, machinery represents a major cost; therefore, good fleet management can have a great impact on the producer’s profit, especially considering the increasing costs of fuel and production inputs in recent years. One of the tasks to be accomplished in order to improve fleet management is planning the path that the machine should take to cover the field while working. Information such as distance traveled, time and fuel consumption as well as agricultural inputs wasted due to off-target-application areas are crucial in the path planning process. Parameters such as field boundary size and geometry, machine total width as …

Evaluating The Effectiveness Of Weep Berm Systems For Treating Runoff From A Horse Muck Composting Operation, Ross L. Guffey

Theses and Dissertations--Biosystems and Agricultural Engineering

Two contour weep berms systems were designed and implemented to evaluate their performance at mitigating water quantity problems from a horse muck composting operation. The field-scale study focused on the hydrologic response of a standard contour weep berm and a modified contour weep berm. The modified contour weep berm incorporated a woodchip trench upgradient of a typical standard contour weep design. Monitoring occurred from July 2011 through spring 2012. Eight storm events produced measureable runoff for the standard contour weep berm; however, only five storm events produced measurable runoff for the modified contour weep berm. The largest storm event occurred …

Development And Deployment Of A Bioreactor For The Removal Of Sulfate And Manganese From Circumneutral Coal Mine Drainage, C. B. Mastin, J. D. Edwards, Christopher D. Barton, Anastasios D. Karathanasis, Carmen T. Agouridis, Richard C. Warner

Forestry and Natural Resources Faculty Publications

Surface mining, in the form of contour mining and mountain-top removal, is a common means for retrieving coal in the Appalachian Coal Belt region of Kentucky. Overburden or excess spoil generated by these two methods is placed in valley fills. Traditionally Constructed fills have been shown to adversely impact headwater ecosystems via stream burial and through alterations to the hydrology, sediment supply, water quality and biological composition of downstream reaches. Mine drainages emanating from the toe of valley fills often contain elevated levels of total dissolved solids and heavy metals. Drainage chemistry from Guy Cove, a valley fill located in …

Evaluation Of Algae Concentration In Manure Based Media, Maira Freire Pecegueiro Do Amaral

Theses and Dissertations--Biosystems and Agricultural Engineering

Algae can be used to treat wastewater and manure while producing a feedstock for renewable energy. Algae require nutrients to achieve their maximum growth and manure could provide those nutrients, thereby reducing the cost of algae production and the impact of manure treatment. Algae concentration during cultivation is a critical variable that is difficult to measure due to the high concentration of suspended solids present in manure. This dissertation addresses methods to measure algae concentration in the presence of manure solids.

Quantifying the algae concentration gravimetrically or by optical density was unreliable due to manure solids interfering with the measurement. …

Automated System To Improve Levelness Of Reconstructed Soil, Venkata Srikiran Bodapati, Larry G. Wells

Biosystems and Agricultural Engineering Faculty Publications

Extraction of coal, ores, and minerals from the earth by surface mining has occurred for many years and has always presented a significant challenge with regard to restoration of productive soil to mined areas. Federal and state regulations require that land should be returned to pre-mine productivity or reclaimed as per specific standards following mining. Excessive compaction of reconstructed soil caused by traffic of heavy earth moving equipment has been an enduring challenge regarding successful restoration of soil. A mechanical system was previously designed and developed to reconstruct soil to a depth of 1.22 m (48 in.) while completely avoiding …