Bioresource and Agricultural Engineering Commons^™

Synthesis And Characterization Of Starch Acetates With High Substitution, Yixiang Xu, Vesselin Miladinov, Milford A. Hanna

Industrial Agricultural Products Center: Publications and Information

Acetylation of high-amylose (70%) maize starch to high degree of substitution (DS) was studied by reacting starch with acetic anhydride using 50% aqueous NaOH as the catalyst. DS increased with increasing reaction times and increasing ratios of acetic anhydride to starch. Reaction efficiency (RE) increased with longer reaction times and decreased with increases in the ratios of acetic anhydride to starch for extended reaction times. Increasing the amount of NaOH increased both DS and RE. A series of starch acetates with DS values of 0.57-2.23 were prepared and their crystalline structures, chemical structures, thermal stability, and morphological properties were investigated. …

Rapid Field Evaluation Of Drip And Microspray Distribution Uniformity, Charles M. Burt

BioResource and Agricultural Engineering

The Cal Poly ITRC irrigation evaluation programs have been widely used to assess the global distribution uniformity (DU) of drip and microsprayer irrigation systems. The field procedures and formulas used in the program are presented in this paper. The system DU is estimated by mathematically combining the component DU values. DU components include pressure differences, "other causes" (such as manufacturing variation, plugging, and wear), unequal drainage, and unequal application rates. Results are presented from evaluations by several entities, including Cal Poly ITRC. Cal Poly evaluations of 329 fields provided an average DU_lq of 0.85 for drip and 0.80 for …

An In Situ Cell For Characterization Of Solids By Soft X-Ray Absorption, Ian J. Drake, Teris C. N. Liu, Mary Gilles, Tolek Tyliszczak, A. L. D. Kilcoyne, David K. Shuh, Richard A. Mathies, Alexis T. Bell

United States Department of Energy: Publications

A cell has been designed and fabricated for in situ characterization of catalysts and environmental materials using soft x-ray absorption spectroscopy and spectromicroscopy at photon energies above 250 eV. “Lab-on-a-chip” technologies were used to fabricate the cell on a glass wafer. The sample compartment is 1.0 mm in diameter and has a gas path length of 0.8 mm to minimize x-ray absorption in the gas phase. The sample compartment can be heated to 533 K by an Al resistive heater and gas flows up to 5.0 cm³ min⁻¹ can be supplied to the sample compartment through microchannels. The …

Vertical Wall Loads In A Model Grain Bin With Non-Axial Internal Inserts, Marek Molenda, Michael D. Montross, Jozef Horabik, Sidney A. Thompson

Biosystems and Agricultural Engineering Faculty Publications

A study was conducted to estimate the degree of load asymmetry in a bin with non-axial internal inserts. Internal inserts in the form of an annulus segment were attached to the wall, and their influence on vertical wall loads during centric filling and discharge in a model bin were measured. Wall and floor loads were measured in a corrugated-wall model grain bin with a diameter of 2.44 m and a height of 7.3 m filled with soft red winter wheat to a depth of 6.7 m (height-to-diameter ratio of 2.75). Tests were conducted with inserts that extended circumferentially 30°, 60°, …

Seasonal Aeration Rates For The Eastern United States Based On Long-Term Weather Patterns, Michael D. Montross, Samuel G. Mcneill, Thomas C. Bridges

Biosystems and Agricultural Engineering Faculty Publications

Most aeration fans are sized to produce a minimum airflow rate of 0.1 m³/min/t (0.1 cfm/bu) in on-farm grain storage structures. At this airflow rate a significant amount of time is required to move a cooling front completely through a bin. The desired grain temperature and prevailing weather conditions will have a significant effect on required fan size. Thirty years of weather data were analyzed for the eastern United States to determine the amount of time available in temperature windows between 0 to 15.C and 0 to 17.C. Contour maps were generated with ArcMap 8.3 for the percentage …

Suitability Of A Gps Collar For Grazing Studies, Carmen T. Agouridis, Timothy S. Stombaugh, Stephen R. Workman, Benjamin K. Koostra, Dwayne R. Edwards, Eric S. Vanzant

Biosystems and Agricultural Engineering Faculty Publications

The traditional means of tracking animal location in a field is by visual observation. Not only is this method labor intensive, it is also prone to error as the observer can alter cattle movement, observation periods are often too short to obtain confidence in general daily behavior patterns, and observer fatigue becomes an issue. In the 1990s, the University of Kentucky began using GPS collars on cattle to track their position with the goal of incorporating this information into cattle management practices. One of the key unanswered questions regarding the GPS collars is the accuracy of the position data recorded …

Post-Tier Rail And Typar® Or Metal-Covered Tobacco Field Curing Structures, George A. Duncan

Agricultural Engineering Extension Publications

Tobacco producers are rapidly adopting field curing structures with several variations in construction materials and methods. They are looking to lower costs and increase efficiency by installing structures that require less maintenance and last longer.

Two recently designed structures appear to provide more permanent options for producers who dislike the tedious tasks of covering and securing the plastic over the tobacco during the curing season. Both structures use two-rail-wide, two-post wooden construction, but they differ in their roof coverings. One uses Typar®, and the other uses metal.

Effect Of Moisture Content And Broken Kernels On The Bulk Density And Packing Of Corn, Samuel G. Mcneill, Sidney A. Thompson, Michael D. Montross

Biosystems and Agricultural Engineering Faculty Publications

Shelled yellow dent corn samples were conditioned to three moisture content levels (12%, 15%, and 18% w.b.) and mixed with a prescribed amount of broken corn particles of known size (geometric mean diameter of 1.0, 1.4, 2.0, 2.8, and 4.0 mm) and concentration (2.5%, 5.0%, and 7.5% by weight) levels. The initial bulk density and grain compaction under simulated overburden pressure tests were determined for each sample. Uniaxial compression tests were performed for seven vertical pressure levels (3.4, 6.9, 14, 28, 55, 110, and 165 kPa) with a minimum of three replications each. Tests were performed at two locations with …

Genetic Algorithm-Based Model For Determination Of Efficient Management Strategies For Irrigation Canal Networks, Talaat Taher El Gamel

Civil & Environmental Engineering Theses & Dissertations

An optimization model for the determination of efficient management strategies for an irrigation canal network is developed. The objective is to minimize the total water consumed while satisfying various system constraints. An unsteady flow model is used to simulate the flow in the network. A genetic algorithm- (GA-) based framework is used to solve the model. The suitable GA parameters that should be used within the model, as well as the performance of various constraint-handling techniques, are studied. Uncertainties in crop pattern and water consumption rates are incorporated into the search procedure to identify more reliable solutions. A graphical interface …

A Nebraska Odor Footprint Tool For Planning Pork Facilities, Richard Koelsch

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Pork producers and rural communities are struggling to balance air quality issues (primarily odors) with the presence and growth of the industry. Currently the type of pork facility, odor control measures, prevailing wind direction, atmospheric conditions, and a community's tolerance to some degree of odor are largely ignored in the planning process because scientific tools that incorporate this information are lacking. Without such tools, decisions on setback distances and acceptable type and size of facilities are influenced by a range of arguments, often emotional in nature. In addition, pork producers lack tools to assist in evaluating impact on a rural …

Zone Heating For Wean-To-Finish Facilities: A Performance Comparison, Rick R. Stowell

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Farm research trials were conducted in 2003 and 2004 to assess the effects of the type of zone heater and floor mat used in a wean-to-finish building on the thermal environment created for newly weaned pigs and resulting pig performance. Modulated LP gas-fired brooder heaters were compared to electric heat lamps, and floor mats made from farm-cut wood sheathing (3/8” oriented-strand board, OSB) were compared to commercial [unheated] rubber mats in a replicated 2x2 factorial experiment. No consistent differences in air temperature near the heating zone were found between either of the treatments, with treatment means within 1^oF …

The Influence Of Environmental Temperature And Substrate Initial Moisture Content On Aspergillus Niger Growth And Phytase Production In Solid−State Cultivation, Seaborn B. Carter, Sue E. Nokes, Czarena L. Crofcheck

Biosystems and Agricultural Engineering Faculty Publications

Aspergillus niger is being used commercially for phytase production utilizing solid-state cultivation; however, no studies have been published that investigated the optimal environmental temperature and initial substrate water content to maximize fungal growth and/or phytase production. Solid-state cultivations of Aspergillus niger on wheat bran and soybean meal were conducted at three temperatures (25°C, 30°C, and 35°C) and three initial moisture contents (50%, 55%, and 60% wet basis) in a split-plot full-factorial experimental design. Fermentations were conducted for 0, 24, 48, 72, and 120 h. The containers were sampled destructively and assayed for phytase activity and glucosamine concentration as an estimate …

Effect Of Stover Fraction On Glucose Production Using Enzymatic Hydrolysis, Czarena L. Crofcheck, Michael D. Montross

Biosystems and Agricultural Engineering Faculty Publications

Corn stover was fractionated into three fractions: cobs, stalks, and leaves and husks. The fractions were dried and ground through a 2 mm screen. Samples of the three fractions and whole corn stover with and without NaOH pretreatment were subjected to enzymatic hydrolysis in order to determine the effect of fractionation on glucose production. The average amounts of glucose released after 60 h of hydrolysis from pretreated cobs, leaves and husks, stalks, and whole stover were 0.50, 0.36, 0.28, and 0.36 g/g dry biomass, respectively. The average amounts of glucose released after 60 h of hydrolysis from nonpretreated cobs, leaves …

Irrigation District Observations On Large Diameter, Low Pressure Pipeline Materials, Charles M. Burt

BioResource and Agricultural Engineering

There are approximately 1,400 miles of low pressure non-reinforced cast-in-place ("monolithic" or "CIP") concrete pipe in California irrigation districts. Cast-in-place pipe was irrigation districts’ material of choice for large diameter pipelines from 1930 to at least 1980. Many of these pipelines were installed in the early 1900’s. They are predominately found on the east side of the San Joaquin Valley, from Manteca in the north to Visalia in the south. Most of these pipes are deteriorating and will need to be replaced within the next 10-20 years.

Irrigation districts have attempted to find new ways to repair these pipes. However, …

Using Covers To Minimize Odor And Gas Emissions From Manure Storages, José R. Bicudo, David R. Schmidt, Larry D. Jacobson

Agricultural Engineering Extension Publications

Odor emissions from animal production sites are typically the leading cause of nuisance complaints. Locating facilities far from neighbors is often a solution to the odor problem, but this is not always an option for producers. Most often, reducing odor emissions from the farm is the only option available.

Benchmarking Of Flexibility And Needs - 2004, Charles Burt, Dan Howes, Franklin Gaudi, Monica Holman

BioResource and Agricultural Engineering

ITRC interviewed irrigation district personnel from 25 agricultural districts in eastern Washington, northern Idaho and western Montana.

Data were analyzed to determine the degree of water delivery flexibility provided to farmers and the extent of existing and planned district modernization. This is the fourth such report the Irrigation Training and Research Center (ITRC) has published for irrigation districts in the western US. The first two evaluations were conducted on behalf of the Mid-Pacific Region of the US Bureau of Reclamation (USBR) and included California irrigation districts that had long-term federal contracts. The third report was prepared on behalf of the …

Biotransformation Of Two-Line Silica-Ferrihydrite By A Dissimilatory Fe(Iii)-Reducing Bacterium: Formation Of Carbonate Green Rust In The Presence Of Phosphate, Ravi K. Kukkadapu, John M. Zachara, James K. Fredrickson, David W. Kennedy

United States Department of Energy: Publications

The reductive biotransformation of two Si-ferrihydrite coprecipitates (1 and 5 mole % Si) by Shewanella putrefaciens, strain CN32, was investigated in 1,4-piperazinediethanesulfonic acid-buffered media (pH ~7) with lactate as the electron donor. Anthraquinone-2,6-disulfonate, an electron shuttle, was present in the media. Experiments were performed without and with PO₄^3- (P) (1 to 20 mmol/L) in media containing 50 mmol/L Fe. Our objectives were to define the combined effects of SiO₄^{4 -} (Si) and P on the bioreducibility and biomineralization of ferrihydrites under anoxic conditions. Iron reduction was measured as a function of time, solids were characterized …

A Cation Exchange Model To Describe Cs+ Sorption At High Ionic Strength In Subsurface Sediments At Hanford Site, Usa, Chongxuan Liu, John M. Zachara, Steven Smith

United States Department of Energy: Publications

A theoretical and experimental study of cation exchange in high ionic strength electrolytes was performed using pristine subsurface sediments from the U.S. Department of Energy Hanford site. These sediments are representative of the site contaminated sediments impacted by release of high level waste (HLW) solutions containing ¹³⁷Cs⁺ in NaNO₃ brine. The binary exchange behavior of Cs⁺–Na⁺, Cs⁺–K⁺, and Na⁺–K⁺ was measured over a range in electrolyte concentration. Vanselow selectivity coefficients (K_v) that were calculated from the experimental data using Pitzer model ion activity …

Water Level Sensor Testing Summary, Stuart Styles, Sarah Herman, Marcus Yasutake, Chuck Keezer

BioResource and Agricultural Engineering

The findings presented here are the continuation of a series of studies begun in 1998 by the Irrigation Training and Research Center (ITRC) at California Polytechnic State University (Cal Poly), San Luis Obispo, California, on behalf of the Mid-Pacific Region of the United States Bureau of Reclamation (USBR) to test water level sensors under a variety of hydraulic conditions.

The goals for the original project were to determine the best way to monitor water level, and to develop a fast method for appraising sensors considered for irrigation district applications. This research addresses the need for water level sensors that are …

Biogeochemical Transformation Of Fe Minerals In A Petroleum-Contaminated Aquifer, John M. Zachara, Ravi K. Kukkadapu, Paul L. Gassman, Alice Dohnalkova, Jim K. Fredrickson, Todd Anderson

United States Department of Energy: Publications

The Bemidji aquifer in Minnesota, USA is a well-studied site of subsurface petroleum contamination. The site contains an anoxic groundwater plume where soluble petroleum constituents serve as an energy source for a region of methanogenesis near the source and bacterial Fe(III) reduction further down gradient. Methanogenesis apparently begins when bioavailable Fe(III) is exhausted within the sediment. Past studies indicate that Geobacter species and Geothrix fermentens–like organisms are the primary dissimilatory Fe-reducing bacteria at this site. The Fe mineralogy of the pristine aquifer sediments and samples from the methanogenic (source) and Fe(III) reducing zones were characterized in this study to …

Reduction Of Tco4- By Sediment-Associated Biogenic Fe(Ii), James K. Fredrickson, John M. Zachara, David W. Kennedy, Ravi K. Kukkadapu, James P. Mckinley, Steve M. Heald, Chongxuan Liu, Andrew E. Plymale

United States Department of Energy: Publications

The potential for reduction of ⁹⁹TcO₄^-_(aq) to poorly soluble ⁹⁹TcO₂ · nH₂O_(s) by biogenic sediment-associated Fe(II) was investigated with three Fe(III)-oxide containing subsurface materials and the dissimilatory metal-reducing subsurface bacterium Shewanella putrefaciens CN32. Two of the subsurface materials from the U.S. Department of Energy’s Hanford and Oak Ridge sites contained significant amounts of Mn(III,IV) oxides and net bioreduction of Fe(III) to Fe(II) was not observed until essentially all of the hydroxylamine HCl-extractable Mn was reduced. In anoxic, unreduced sediment or where Mn oxide bioreduction was incomplete, exogenous biogenic TcO_{2 …}

Synthesis Of Colloidal Mn2+:Zno Quantum Dots And High-Tc Ferromagnetic Nanocrystalline Thin Films, Nick S. Norberg, Kevin R. Kittilstved, James E. Amonette, Ravi K. Kukkadapu, Dana A. Schwartz, Daniel R. Gamelin

United States Department of Energy: Publications

We report the synthesis of colloidal Mn²⁺-doped ZnO (Mn²⁺:ZnO) quantum dots and the preparation of room-temperature ferromagnetic nanocrystalline thin films. Mn²⁺:ZnO nanocrystals were prepared by a hydrolysis and condensation reaction in DMSO under atmospheric conditions. Synthesis was monitored by electronic absorption and electron paramagnetic resonance (EPR) spectroscopies. Zn(OAc)₂ was found to strongly inhibit oxidation of Mn²⁺ by O₂, allowing the synthesis of Mn2+:ZnO to be performed aerobically. Mn2+ ions were removed from the surfaces of as-prepared nanocrystals using dodecylamine to yield high-quality internally doped Mn2+:ZnO colloids of nearly spherical shape …

Assessing Conceptual Models For Subsurface Reactive Transport Of Inorganic Contaminants, J.A. Davis, S.B. Yabusaki, C.I. Steefel, John M. Zachara, G.P. Curtis, G.D. Redden, L.J. Criscenti, B.D. Honeyman

United States Department of Energy: Publications

In many subsurface situations where human health and environmental quality are at risk (e.g., contaminant hydrogeology, petroleum extraction, carbon sequestration, etc.), scientists and engineers are being asked by federal agency decision-makers to predict the fate of chemical species under conditions where both reactions and transport are processes of first-order importance.

In 2002, a working group (WG) was formed by representatives of the U.S. Geological Survey, Environmental Protection Agency,Department of Energy,Nuclear Regulatory Commission, Department of Agriculture,and Army Engineer Research and Development Center to assess the role of reactive transport modeling (RTM) in addressing these situations. Specifically, the goals of the WG …

Cryogenic Laser Induced Fluorescence Characterization Of U(Vi) In Hanford Vadose Zone Pore Waters, Zheming Wang, John M. Zachara, Wassana Yantasee, Paul Gassman, Chongxuan Liu, Alan Joly

United States Department of Energy: Publications

Ambient and liquid helium temperature laser-induced time-resolved uranyl fluorescence spectroscopy was applied to study the speciation of aqueous uranyl solutions containing carbonate and phosphate and two porewater samples obtained by ultracentrifugation of U(VI)-contaminated sediments. The significantly enhanced fluorescence signal intensity and spectral resolution found at liquid helium temperature allowed, for the first time, direct fluorescence spectroscopic observation of the higher aqueous uranyl complexes with carbonate: UO₂(CO₃)₂ ^2-, UO₂(CO₃)₃ ^4-, and (UO₂)₂(OH)₃CO₃ ^-. The porewater samples were non-fluorescent at room temperature. …

Microscale Distribution Of Cesium Sorbed To Biotite And Muscovite, James Mckinley, John M. Zachara, Steven Heald, Alice Dohnalkova, Matthew Newville, Steve Sutton

United States Department of Energy: Publications

Individual 1-3 mm biotite and muscovite clasts from Hanford sediment were contacted with 0.08 M CsNO₃. They were examined using electron or X-ray microprobe methods, as intact specimens or sectioned perpendicular to their basal planes. Cs+ was observed to preferentially sorb to mica edges, steps on mica surfaces, or fractured regions. The localization of Cs conformed to hypothesized strong binding to frayed edge sites in preference to sites on basal planes. In section, Cs⁺ was found to penetrate the mica interior, forming discrete zones of concentration, particularly in muscovite. In biotite, Cs was more abundant, permeating the …

Spectroscopic And Diffraction Study Of Uranium Speciation In Contaminated Vadose Zone Sediments From The Hanford Site, Washington State, Jeffrey Catalano, Steven Heald, John M. Zachara, Gordon Brown Jr.

United States Department of Energy: Publications

Contamination of vadose zone sediments under tank BX-102 at the Hanford site, Washington, resulted from the accidental release of 7-8 metric tons of uranium dissolved in caustic aqueous sludge in 1951. We have applied synchrotron-based X-ray spectroscopic and diffraction techniques to characterize the speciation of uranium in samples of these contaminated sediments. U L_III-edge X-ray absorption fine structure (XAFS) spectroscopic studies demonstrate that uranium occurs predominantly as a uranium- (VI) silicate from the uranophane group of minerals. XAFS cannot distinguish between the members of this mineral group due to the near identical local coordination environments of uranium in …

Biogeochemical Transformation Of Fe Minerals In A Petroleum-Contaminated Aquifer, John M. Zachara, Ravi K. Kukkadapu, Paul Gassman, Alice Dohnalkova, James K. Fredrickson, Todd Anderson

United States Department of Energy: Publications

The Bemidji aquifer in Minnesota, USA is a well-studied site of subsurface petroleum contamination. The site contains an anoxic groundwater plume where soluble petroleum constituents serve as an energy source for a region of methanogenesis near the source and bacterial Fe(III) reduction further down gradient. Methanogenesis apparently begins when bioavailable Fe(III) is exhausted within the sediment. Past studies indicate that Geobacter species and Geothrix fermentens–like organisms are the primary dissimilatory Fe-reducing bacteria at this site. The Fe mineralogy of the pristine aquifer sediments and samples from the methanogenic (source) and Fe(III) reducing zones were characterized in this study to …

Chromium Speciation And Mobility In A High Level Nuclear Waste Vadose Zone Plume, John M. Zachara, Calvin Ainsworth, Gordon Brown Jr., Jeffery Catalano, James Mckinley, Odeta Qafoku, Steven Smith, James Szecsody, Sam Traina, Jeffrey Warner

United States Department of Energy: Publications

Radioactive core samples containing elevated concentrations of Cr from a high level nuclear waste plume in the Hanford vadose zone were studied to assess the future mobility of Cr. Cr(VI) is an important subsurface contaminant at the Hanford Site. The plume originated in 1969 by leakage of self-boiling supernate from a tank containing REDOX process waste. The supernate contained high concentrations of alkali (NaOH ≈ 5.25 mol/L), salt (NaNO₃/NaNO₂ >10 mol/L), aluminate [Al(OH)₄ ⁻ = 3.36 mol/L], Cr(VI) (0.413 mol/L), and ¹³⁷Cs⁺(6.51 X 10^-5 mol/L). Water and acid extraction of the oxidized …

Dissolution Of Uranyl Microprecipitates In Subsurface Sediments At Hanford Site, Usa, Chongxuan Liu, John M. Zachara, Odeta Qafoku, James Mckinley, Steve M. Heald, Zheming Wang

United States Department of Energy: Publications

The dissolution of uranium was investigated from contaminated sediments obtained at the US. Department of Energy (U.S. DOE) Hanford site. The uranium existed in the sediments as uranyl silicate microprecipitates in fractures, cleavages, and cavities within sediment grains. Uranium dissolution was studied in Na, Na-Ca, and NH₄ electrolytes with pH ranging from 7.0 to 9.5 under ambient CO₂ pressure. The rate and extent of uranium dissolution was influenced by uranyl mineral solubility, carbonate concentration, and mass transfer rate from intraparticle regions. Dissolved uranium concentration reached constant values within a month in electrolytes below pH 8.2, whereas concentrations continued …

Scintillator Detectors For Scanning Transmission X-Ray Microscopes At The Advanced Light Source, S. Fakra, A. L. D. Kilcoyne, Tolek Tyliszczak

United States Department of Energy: Publications

The choice of x-ray detectors presents a challenge for scanning transmission x-ray microscopes (STXM). The ultimate detector for the ALS STXMs should have a very high efficiency over a wide energy range, single photon counting capabilities up to 1GHz, high rejection of red laser light, fast response, and work in both vacuum and at atmospheric pressure. The results of an investigation using a photomultiplier tube (PMT) with a number of different scintillators are presented. The PMT is used in photon counting and analog modes. Scintillators used for this study include commercially available phosphor powders and various single crystals.