Digital Commons Network^™

Gopher Intrusion In Cropping Systems, Kenneth Romero, Paul Cardinalli

Agricultural Education and Communication

The purpose of this project was to determine if no till vs. till on gopher populations was more beneficial. Which is more efficient at controlling gophers and explain the damage they can cause and the diseases they can potentially vector. What are the different options of pest managements that have to be used when dealing with a gopher infestation in a tilled field vs. a no-tilled field.

Weeds, Nitrogen, And Yield: Measuring The Effectiveness Of An Organic No-Till System, David Robb

All Theses

Previous research in the mid-Atlantic and midwestern USA has identified advantages and drawbacks of "organic no-till" vegetable production, but few studies have been conducted in the warmer southeastern region. The purpose of this study was to examine the effects of tillage [no-till (NT) vs. conventional tillage (CT) of a cereal rye/crimson clover cover crop] and three nitrogen fertilization rates on organic tomato (Solanum lycopersicum L.) and summer squash (Cucurbita pepo L.) yield, weed suppression, and soil N dynamics in two years in a soil series in Clemson, SC. Squash yields were similar between tillage treatments in both years. NT tomato …

Synthesis And Characterization Of Neo-Confused Porphyrins And Related Systems, Arwa Salem Almejbel

Theses and Dissertations

Carbaporphyrins have been the focus of many studies, and a wide variety of related carbaporphyrinoid systems have been reported. N-confused porphyrins are a class of carbaporphyrins where one pyrrole unit has been inverted. In this work, a newly discovered family of porphyrin isomers where one of the pyrrolic subunits is connected to the meso-bridges in a 1,3-fashion, called neo-confused porphyrins, has been investigated.

Reaction of pyrrole-3-carbaldehydes with acetoxymethylpyrroles and NaH in DMF gave neo-confused dipyrrylmethane dialdehydes. The resulting dialdehydes underwent an acid catalyzed condensation with a dipyrrylmethane to give neo-confused phlorins, and following oxidation with FeCl3 afforded new neo-confused porphyrins. …

Post-Its And Priorities: A Participatory Exercise For Understanding Perspectives Of Diverse Stakeholders, James Lachance, Mitch Hunter, Denise Finney

The Journal of Extension

We describe a participatory co-learning exercise that can help elucidate and navigate the unique perspectives of farmers, researchers, Extension personnel, and other agricultural professionals engaged in managing complex systems. We developed the exercise to help a diverse advisory panel collaboratively identify and prioritize ecosystem services for measurement in an experiment on cover crop mixtures. Post-event evaluations were positive and suggest that the exercise is a useful tool for participatory research projects or Extension programs involving a diverse group of stakeholders and complex systems.

Removal Of Trace Organic Contaminants By An Mbr Comprising A Mixed Culture Of Bacteria And White-Rot Fungi, Luong Nguyen, Faisal Hai, Shufan Yang, Jinguo Kang, Frederic Leusch, Felicity Roddick, William Price, Long Nghiem

Faisal I Hai

The degradation of 30 trace organic contaminants (TrOC) by a white-rot fungus-augmented membrane bioreactor (MBR) was investigated. The results show that white-rot fungal enzyme (laccase), coupled with a redox mediator (1-hydroxy benzotriazole, HBT), could degrade TrOC that are resistant to bacterial degradation (e.g. diclofenac, triclosan, naproxen and atrazine) but achieved low removal of compounds (e.g. ibuprofen, gemfibrozil and amitriptyline) that are well removed by conventional activated sludge treatment. Overall, the fungus-augmented MBR showed better TrOC removal compared to a system containing conventional activated sludge. The major role of biodegradation in removal by the MBR was noted. Continuous mediator dosing to …

Enhancement Of Removal Of Trace Organic Contaminants By Powdered Activated Carbon Dosing Into Membrane Bioreactors, Ngoc Luong Nguyen, Faisal Ibney Hai, Long Nghiem, Jinguo Kang, William Price, Chul Park, Kazuo Yamamoto

Faisal I Hai

This study compared the removal efficiency of 22 widespread trace organic contaminants by a laboratory-scale membrane bioreactor (MBR) with and without direct addition of powdered activated carbon (PAC) into the activated sludge reactor over a period of 312 days. The removal of hydrophilic and biologically persistent trace organic contaminants was immediately improved to above 95% after the addition of PAC into MBR. However, a compound-specific gradual decrease in removal underscored the requirement for the addition of fresh PAC. Adsorption onto PAC-added sludge appeared to play a significant role in the relatively more effective aqueous phase removal of a few resistant …

Wastewater Reuse: Removal Of Emerging Trace Organic Contaminants (Troc), Faisal Hai, Long Nghiem, Stuart Khan, William Price, Kazuo Yamamoto

Faisal I Hai

This chapter reviews current and new technologies for the removal of emerging TrOC from wastewater for reuse purposes. In particular, it compares the relative performance of Membrane bioreactors (MBR) with other conventional biological processes. It is shown that MBR has many intrinsic advantages over other methods leading to superior performance. Fundamental to this is the presence of a membrane barrier which provides a range of other adsorption mechanisms for TrOC. However, in practice there are many factors affecting TrOC removal by MBR, leading to sometimes conflicting reports in the literature from both lab scale studies as well as full scale …

Removal Of Emerging Trace Organic Contaminants By Mbr-Based Hybrid Treatment Processes, Luong Nguyen, Faisal Ibney Hai, Jinguo Kang, William E. Price, Long D. Nghiem

Faisal I Hai

The aim of this study was to demonstrate the complementarity of combining membrane bioreactor (MBR) treatment with UV oxidation or high pressure membrane filtration processes such as nanofiltration (NF) or reverse osmosis (RO) for the removal of trace organic contaminants (TrOC). The results suggest that the removal mechanisms of TrOC by either UV oxidation or NF/RO membrane filtration differ significantly from those of an MBR system. Thus, they can complement MBR treatment very well to significantly improve the removal of TrOC. MBR treatment can effectively remove hydrophobic and readily biodegradable hydrophilic TrOC. The remaining hydrophilic and biologically persistent TrOC were …

Enhancement Of Trace Organic Contaminant Degradation By Crude Enzyme Extract From Trametes Versicolor Culture: Effect Of Mediator Type And Concentration, Ngoc Luong Nguyen, Faisal Ibney Hai, Jinguo Kang, Frederic Leusch, Felicity Roddick, S Faraj Magram, William Price, Long Nghiem

Faisal I Hai

The performance of two redox mediating compounds, namely 1-hydroxybenzotriazole (HBT) and syringaldehyde (SA), was compared in terms of enhancement of enzymatic degradation of a diverse set of 14 phenolic and 16 non-phenolic trace organic contaminants (TrOCs) and the toxicity of the treated media. Extracellular enzyme extract (predominantly containing laccase) from Trametes versicolor culture achieved efficient degradation (70-95%) of nine phenolic and one non-phenolic TrOCs. Mediator dosing extended the spectrum of efficiently degraded TrOCs to 13 phenolic and three non-phenolic compounds, with moderate improvements in removal of a few other non-phenolic compounds. TrOC removal efficiency improved significantly as the HBT dose …

Impact Of 1-Hydroxybenzotriazole Dosing On Trace Organic Contaminant Degradation By Laccase, Ngoc Luong Nguyen, Faisal Ibney Hai, Jinguo Kang, S Faraj Magram, William Price, Long Nghiem

Faisal I Hai

This study investigated the removal of five selected non-phenolic trace organic contaminants (TrOC) by extracellular enzyme extract from a white-rot fungus. Except diclofenac, no other investigated non-phenolic TrOC were degraded by the extracellular enzyme extract. Improvement of enzymatic degradation of all TrOC was achieved in the presence of a redox mediator, namely, 1-hydroxybenzotriazole (HBT). However, the enhancement of degradation was mediator concentration-specific. A significant improvement in degradation at higher dosage than 0.1 mM (HBT) was achieved.

Comparison Between Sequential And Simultaneous Application Of Activated Carbon With Membrane Bioreactor For Trace Organic Contaminant Removal, Luong N. Nguyen, Faisal I. Hai, Jinguo Kang, Long D. Nghiem, William E. Price, Wenshan Guo, Huu H. Ngo, Kuo-Lun Tung

Faisal I Hai

The removal efficiency of 22 selected trace organic contaminants by sequential application of granular activated carbon (GAC) and simultaneous application of powdered activated carbon (PAC) with membrane bioreactor (MBR) was compared in this study. Both sequential application of GAC following MBR treatment (MBR–GAC) and simultaneous application of PAC within MBR (PAC–MBR) achieved improved removal (over 95%) of seven hydrophilic and biologically persistent compounds, which were less efficiently removed by MBR-only treatment (negligible to 70%). However, gradual breakthrough of these compounds occurred over an extended operation period. Charged compounds, particularly, fenoprop and diclofenac, demonstrated the fastest breakthrough (complete and 50–70%, in …

Coupling Granular Activated Carbon Adsorption With Membrane Bioreactor Treatment For Trace Organic Contaminant Removal: Breakthrough Behaviour Of Persistent And Hydrophilic Compounds, Luong N. Nguyen, Faisal I. Hai, William E. Price, Jinguo Kang, Long D. Nghiem

Faisal I Hai

This study investigated the removal of trace organic contaminants by a combined membrane bioreactor - granular activated carbon (MBR-GAC) system over a period of 196 days. Of the 22 compounds investigated here, all six hydrophilic compounds with electron-withdrawing functional groups (i.e., metronidazole, carbamazepine, ketoprofen, naproxen, fenoprop and diclofenac) exhibited very low removal efficiency by MBR-only treatment. GAC post-treatment initially complemented MBR treatment very well; however, a compound-specific gradual deterioration of the removal of the above-mentioned problematic compounds was noted. While a 20% breakthrough of all four negatively charged compounds namely ketoprofen, naproxen, fenoprop and diclofenac occurred within 1000-3000 bed volumes …

Rejection And Fate Of Trace Organic Compounds (Trocs) During Membrane Distillation, Kaushalya Wijekoon, Faisal Ibney Hai, Jinguo Kang, William E. Price, Tzahi Cath, Long D. Nghiem

Faisal I Hai

In this study, we examined the feasibility of membrane distillation (MD) for removing trace organic compounds (TrOCs) during water and wastewater treatment. A set of 29 compounds was selected to represent major TrOC groups, including pharmaceuticals, steroid hormones, phytoestrogens, UV-filters, industrial chemicals, and pesticides that occur ubiquitously in municipal wastewater. Results reported here suggest that rejection and fate and transport of TrOC during MD are governed by their volatility and, to a lesser extent, hydrophobicity. All TrOCs with pKH > 9 (which can be classified as non-volatile) were well removed by MD. Among the 29 TrOCs investigated in this study, three …

A Novel Membrane Distillation-Thermophilic Bioreactor System: Biological Stability And Trace Organic Compound Removal, Kaushalya Wijekoon, Faisal Hai, Jinguo Kang, William Price, Wenshan Guo, Hao Ngo, Tzahi Cath, Long Nghiem

Faisal I Hai

The removal of trace organic compounds (TrOCs) by a novel membrane distillation-thermophilic bioreactor (MDBR) system was examined. Salinity build-up and the thermophilic conditions to some extent adversely impacted the performance of the bioreactor, particularly the removal of total nitrogen and recalcitrant TrOCs. While most TrOCs were well removed by the thermophilic bioreactor, compounds containing electron withdrawing functional groups in their molecular structure were recalcitrant to biological treatment and their removal efficiency by the thermophilic bioreactor was low (0-53%). However, the overall performance of the novel MDBR system with respect to the removal of total organic carbon, total nitrogen, and TrOCs …

Slides: Food Production: Technical Challenges In Agricultural Water Conservation, Perry Cabot

Innovations in Managing Western Water: New Approaches for Balancing Environmental, Social and Economic Outcomes (Martz Summer Conference, June 11-12)

Presenter: Dr. Perry Cabot, Research Scientist and Extension Specialist, Colorado Water Institute, Colorado State University

35 slides

A Market Study Of Organic And Fair Trade Coffee In Bolivia, Christopher L. Estevez

FIU Electronic Theses and Dissertations

The purpose of this research is to study the commercialization of Fairtrade and Organic coffee in the Bolivia. Fairtrade and Organic coffee are alternative trade systems designed to promote the equitable and environmentally sustainable production of coffee. However, these alternative trading systems often fail to meet these goals. The producers and environment these systems are intended to protect remain marginalized. These failures are due to a number of local institutions. In order to better understand these institutions, this research conducted interviews of various stakeholders including producers, cooperative leaders, organic/Fair Trade certifiers, government agencies and private buyers. All these stakeholders influence …

Poly(3,4-Ethylenedioxythiophene): Dextran Sulfate (Pedot: Ds) - A Highly Processable Conductive Organic Biopolymer, David Harman, Robert Gorkin Iii, Leo Stevens, Brianna Thompson, Klaudia Wagner, Bo Weng, Johnson Chung, Marc In Het Panhuis, Gordon Wallace

Robert Gorkin III

A novel water-dispersible conducting polymer analogous to poly(3,4-dioxythiophene):polystyrene sulfonate (PEDOT:PSS) has been chemically synthesized in a single reaction in high yield. PEDOT:DS, a new member of the polythiophene family, is composed of a complex between PEDOT and the sulfonated polysaccharide polyanion dextran sulfate. Drop-cast films of aqueous suspensions of the material display a native conductivity of up to 7 ± 1 S cm-1, increasing to 20 ± 2 S cm-1 after treatment with ethylene glycol and thermal annealing. Mass ratios of the precursors NaDS and EDOT were varied from 5:1 to 2:1 and a decrease in the NaDS:EDOT ratio produces …

Old Roots And New Shoots: How Locals And Back-To-The-Landers Remade Maine's Local Food Economy, Eileen Hagerman

Maine History

Back-to-the-landers who relocated to Maine in large numbers during the 1970s often lacked traditional rural skills and encountered a variety of agricultural challenges related to the state’s harsh climate and poor soils. Many who remained on the land often did so, at least initially, because they received support from elderly neighbors who still practiced low-input, small-scale farming. These neighbors tended to freely share their knowledge and skills and, in return, often benefited from the young newcomers’ assistance with laborious on-farm tasks. The newcomers worked with their local allies to form organizations, share knowledge, and coordinate marketing efforts tailored to meet …

Isotope-Based Fluvial Organic Carbon (Isofloc) Model: Model Formulation, Sensitivity, And Evaluation, William I. Ford, James F. Fox

Civil Engineering Faculty Publications

Watershed-scale carbon budgets remain poorly understood, in part due to inadequate simulation tools to assess in-stream carbon fate and transport. A new numerical model termed ISOtope-based FLuvial Organic Carbon (ISOFLOC) is formulated to simulate the fluvial organic carbon budget in watersheds where hydrologic, sediment transport, and biogeochemical processes are coupled to control benthic and transported carbon composition and flux. One ISOFLOC innovation is the formulation of new stable carbon isotope model subroutines that include isotope fractionation processes in order to estimate carbon isotope source, fate, and transport. A second innovation is the coupling of …

Minimizing Sheet Resistance Of Organic Photovoltaic Cell Top Contact Electrode Layer: Silver Nanowire Concentration Vs. Conductive Polymer Doping Concentration, Caitlyn Cook

Materials Engineering

The top contact electrode layers of nine organic photovoltaic cells were prepared with two varying factors: three Silver nanowire (AgNW) densities deposited on a conductive polymer doped with three concentrations. Silver’s low sheet resistance of 20-Ω/sq is hypothesized to lower the sheet resistance of the anode layer and thus enhance the overall efficiency of the cell. Four-point probe measurements indicated that increasing AgNW density in the top contact electrode layer of an organic photovoltaic cell significantly reduces sheet resistance from 52.2k-Ω/sq to 18.0 Ω/sq. Although an increase in doping concentration of the conductive polymer reduced sheet resistance in low AgNW …

Farm Newsletter, Usu Student Organic Farm

USU Student Organic Farm Newsletter

As we warm up from the cold season, expect the variety in the shares in increase. For the first few weeks there will be cold hardy plants such as leafy greens and some herbs. By next spring you will be craving our thick dark green spinach! Check out the recipe for ideas of how to use all these fabulous greens in your meals!

Methodology Development In Green Chemistry: Oxoammonium Salt Oxidations And Fluoroform Incorporation, Rebecca J. Wiles

University Scholar Projects

Central to the advancement of small molecule synthesis is the ability to develop methodologies that reimagine well known chemistry in a new, environmentally friendly manner. In this thesis two central themes emerge: oxoammonium salt oxidations and trifluoromethyl incorporation using fluoroform gas. Several projects have been developed surrounding oxoammonium salt chemistry, which are featured by their mild conditions, ease of use, and the metal-free, recyclable nature of the oxidant. Trifluoromethylation using fluoroform gas finds its utility in the use of a potent greenhouse gas waste product as a benchtop reagent.

Economic Assessment Of Organic, Eco-Friendly, And Conventional Peach Production Methods In Northern Utah, Trevor D. Knudsen

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Fruit producers in Northern Utah face several challenges to their production, urbanization, decreased availability of agricultural land, and competition from domestic producers and imports. As consumers are willing to pay premiums for foods differentiated by production method, such as eco-friendly and organic, conversion to these methods may increase the profitability of fruit growing operations.

This study found that consumers in Northern Utah are willing to pay a premium for peaches grown using organic and eco-friendly production practices over conventionally grown peaches. The study also found that of the three methods of peach production examined (conventional, eco-friendly, and organic), organic had …

Methodology Development In Green Chemistry: Oxoammonium Salt Oxidations And Fluoroform Incorporation, Rebecca J. Wiles

Honors Scholar Theses

Central to the advancement of small molecule synthesis is the ability to develop methodologies that reimagine well known chemistry in a new, environmentally friendly manner. In this thesis two central themes emerge: oxoammonium salt oxidations and trifluoromethyl incorporation using fluoroform gas. Several projects have been developed surrounding oxoammonium salt chemistry, which are featured by their mild conditions, ease of use, and the metal-free, recyclable nature of the oxidant. Trifluoromethylation using fluoroform gas finds its utility in the use of a potent greenhouse gas waste product as a benchtop reagent.

China Grows Organic, Gabriella Padgett

Collection of Engaged Learning

In the past two decades, the growth of the organic industry in China has exploded as China reacts to poor food quality and global market demands, as well as heightened environmental degradation. This paper explores the rise of the organic movement, the causes for its success, and the importance of its continued growth.

Forward Not Back: Young People's Search For Community And Farming In Maine, Danielle Walczak

Honors College

In Maine there is a growing body of statistics pointing to the growth of agriculture in the state. Yet with one of the oldest populations in the country, Maine is always asking: how do we bring young people to the state? Farming may be a start. The number of farmers age 34 and under increased 40 percent between 2007 and 2012. Maine is bucking the trend. While most of the country’s farms are decreasing in number and getting bigger in size, Maine farms are increasing in number while staying small. Behind each of these statistics there is a person, a …

Thermal Fluctuations Tunneling In Doped Conjugated Polymers, Troy C. Stedman

USF Tampa Graduate Theses and Dissertations

The possibility of using conducting polymers as organic alternatives to widely used inorganic materials for thermoelectric (TE) applications has received much attention in the past few decades. Since conducting polymers are generally inefficient compared to inorganic TE materials, research into their underlying transport mechanisms is required to improve their efficiency. We use a model based on the effects of local thermal fluctuations to characterize the transport in conducting polymer composites. With this model, full linear responses for the current and electronic heat current are obtained. From these responses, the local temperature dependent conductivity, electronic contribution to the thermal conductivity, and …

Effects Of Aging On Organic Aerosol From Open Biomass Burning Smoke In Aircraft And Laboratory Studies, M J. Cubison, A M. Ortega, P L. Hayes, D K. Farmer, D Day, M J. Lechner, W H. Brune, E Apel, G S. Diskin, J A. Fisher, H E. Fuelberg, A Hecobian, D J. Knapp, T Mikoviny, D Riemer, G W. Sachse, W Sessions, R Weber, A J. Weinheimer, A Wisthaler, J L. Jimenez

Jenny A Fisher

Biomass burning (BB) is a large source of primary and secondary organic aerosols (POA and SOA). This study addresses the physical and chemical evolution of BB organic aerosols. Firstly, the evolution and lifetime of BB POA and SOA signatures observed with the Aerodyne Aerosol Mass Spectrometer are investigated, focusing on measurements at high-latitudes acquired during the 2008 NASA ARCTAS mission, in comparison to data from other field studies and from laboratory aging experiments. The parameter f60 , the ratio of the integrated signal at m/z 60 to the total signal in the organic component mass spectrum, is used as a …

Effects Of Organic And Inorganic Selenium Supplementation During Late Gestation And Early Lactation On Beef Cow-Calf Performance, Christopher Robert Muegge

Open Access Theses

Angus x Simmental cows (n = 48, BW = 594 kg, BCS = 5.26, Age = 2.7), pregnant with male fetuses, were used to determine the effect selenium (Se) source during the last 80 d of gestation and first 108 d of lactation on progeny feedlot performance. At 203 d in gestation, cows were blocked by body weight, age, breed composition, and calf sire, and allotted to 1 of 3 treatments: no Se, inorganic Se, or organic Se. Maternal diets were formulated to contain 10.4% CP and 0.90 Mcal/kg NEg during gestation and 12.1% CP and 1.01 Mcal/kg NEg during …

A Practitioner's Guide To Defending "Natural" Food Labeling Litigation, Lauren E. Handel

Kentucky Journal of Equine, Agriculture, & Natural Resources Law

No abstract provided.