Physical Sciences and Mathematics Commons^™

Engineering, Nutrient Removal, And Feedstock Conversion Evaluations Of Four Corn Stover Harvest Scenarios, Reed L. Hoskinson, Douglas L. Karlen, Stuart J. Birrell, Corey W. Radtke, W. W. Wilhelm

Douglas L Karlen

Crop residue has been identified as a near-term source of biomass for renewable fuel, heat, power, chemicals and other bio-materials. A prototype one-pass harvest system was used to collect residue samples from a corn (Zea mays L.) field near Ames, IA. Four harvest scenarios (low cut, high-cut top, high-cut bottom, and normal cut) were evaluated and are expressed as collected stover harvest indices (CSHI). High-cut top and high-cut bottom samples were obtained from the same plot in separate operations. Chemical composition, dilute acid pretreatment response, ethanol conversion yield and efficiency, and thermochemical conversion for each scenario were determined. Mean grain …

Connectivity Of Coastal And Oceanic Ecosystems: Pelagic Habitat Use By Juvenile Reef Fishes In The Gulf Of Mexico, Katie Bowen

HCNSO Student Theses and Dissertations

The assemblage structure, abundance, biomass, and vertical distribution of juvenile reef fishes in the offshore pelagic habitat of the northern Gulf of Mexico are described as part of the NOAA-supported Offshore Nekton Sampling and Analysis Program. The results presented here are from a 3-month, continuous sampling series in 2011 in which discrete depth strata from 0 to 1500 m were sampled using a 10-m² MOCNESS midwater trawl. This is the first study to examine pelagic juvenile reef fish distributions across the entire oceanic northern Gulf of Mexico seaward of the continental shelf break after the Deepwater Horizon Oil Spill. …

Estimating Herbaceous Biomass Of Grassland Vegetation Using The Reference Unit Method, Eric D. Boyda, Jack L. Bulter, Lan Xu

The Prairie Naturalist

Aboveground net primary production provides valuable information on wildlife habitat, fire fuel loads, and forage availability. Aboveground net primary production in herbaceous plant communities is typically measured by clipping aboveground biomass. However, the high costs associated with physically harvesting plant biomass may prevent collecting sufficient data to account for natural spatial and temporal variability of vegetation at a landscape scale. Various double-sampling techniques have been developed to increase sample size while reducing cost. We applied a biomass estimation technique previously developed for estimating shrub biomass using representative samples or “reference units” to estimate herbaceous grassland biomass. Our reference units consisted …

Production And Harvest Of Microalgae In Wastewater Raceways With Resource Recycling, Alexander Colin Roberts

Master's Theses

Microalgae can be grown on municipal wastewater media to both treat the wastewater and produce feedstock for algae biofuel production. However the reliability of treatment must be demonstrated, as well as high areal algae productivity on recycled wastewater media and efficient sedimentation harvesting. This processes was studied at pilot scale in the present research.

A pilot facility was operated with nine CO₂-supplemented raceway ponds, each with a 33-m² surface area and a 0.3-m depth, continuously from March 6, 2013 through September 24, 2014. The ponds were operated as three sets of triplicates with two sets continuously fed …

Modelling Water Uptake Provides A New Perspective On Grass And Tree Coexistence, Michael G. Mazzacavallo, Andrew Kulmatiski

Wildland Resources Faculty Publications

Root biomass distributions have long been used to infer patterns of resource uptake. These patterns are used to understand plant growth, plant coexistence and water budgets. Root biomass, however, may be a poor indicator of resource uptake because large roots typically do not absorb water, fine roots do not absorb water from dry soils and roots of different species can be difficult to differentiate. In a sub-tropical savanna, Kruger Park, South Africa, we used a hydrologic tracer experiment to describe the abundance of active grass and tree roots across the soil profile. We then used this tracer data to parameterize …

Cover Crop Biomass Production And Water Use In The Central Great Plains, David C. Nielsen, Drew J. Lyon, Gary W. Hergert, Robert K. Higgins, Johnathon D. Holman

David C. Nielsen

The water-limited environment of the semiarid Central Great Plains may not produce enough cover crop biomass to generate benefits associated with cover crop use in more humid regions. There have been reports that cover crops grown in mixtures produce more biomass with greater water use efficiency than single-species plantings. This study was conducted to determine differences in cover crop biomass production, water use efficiency, and residue cover between a mixture and single-species plantings. The study was conducted at Akron, CO, and Sidney, NE, during the 2012 and 2013 growing seasons under both rainfed and irrigated conditions. Water use, biomass, and …

Synthesis, Characterization, And Catalytic Applications Of Porous Transition-Metal Oxide Systems For The Conversion Of Biomass, Anton Gudz

Honors Scholar Theses

The development of innovative strategies and environmentally-friendly resources for the sustainable production of fuels and chemicals from renewable materials has recently received much interest in the scientific world. Among such resources, biomass has enormous potential as a raw material for generation of green fine chemicals to replace the petroleum feedstocks currently in place. Biomass derived carbohydrates can be converted into such valuable platform chemicals as levulinates, 5-hydroxymethyl furfural (HMF), and lactates. In order to catalyze the biomass conversion process, porous transition-metal oxide catalytic systems have been developed in this study. High catalytic activities and potential for reusability of such systems …

Synthesis Of Fluorogenic Probes For Studying Biomass Degradation And Synthesis Of New Antifungal Aminoglycosides, Qian Zhang

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

For the first project, a library of fifteen commercially purchased and synthetic fluorogenic probes were employed for the investigation of biomass degradation using extract of white-rot fungi. These discoveries prove that it is possible to employ fungi for selective degradation or release of hemicelluloses from biomass. This work is supported by Sun Grant Western Regional Center/DOT "Bioprospecting for Enzymes to Break Lignin-Hemicellulose Bond" ($300,000,09/01/2011-08/31/2013)

The second project is focused on synthesizing new aminoglycoside analogs and exploring the potential to revive traditional antibacterial kanamycin as new type of antifungal agents. Although aminoglycosides antibiotics are mainly used as antibacterial agents, this project …

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 …

Cost Effectiveness Of Renewable Energy Policy On Military Installations, Zachary L. Esakof

Honors Theses

In 2007, the United States government issued the National Defense Authorization Act, and Section 2852 mandates that the Department of Defense (DoD) meets 25% of its energy needs from renewable sources by 2025. This paper investigates the production decisions that the DoD faces when increasing its share of renewable energy to meet this objective. A linear programming model is created to solve for the cost-effective renewable energy portfolio mix for each military base to meet its production target of renewable energy. The renewable sources utilized in each base’s energy portfolio include solar, wind, geothermal, and renewably-sourced energy from the grid, …

Evaluating The Long-Term Effects Of Logging Residue Removals In Great Lakes Aspen Forests, Michael I. Premer

Dissertations, Master's Theses and Master's Reports

Commercial aspen (Populus spp.) forests of the Great Lakes region are primarily managed for timber products such as pulp fiber and panel board, but logging residues (topwood and non-merchantable bolewood) are potentially important for utilization in the bioenergy market. In some regions, pulp and paper mills already utilize residues as fuel in combustion for heat and electricity, and progressive energy policies will likely cause an increase in biomass feedstock demand. The effects of removing residues, which have a comparatively high concentration of macronutrients, is poorly understood when evaluating long-term site productivity, future timber yields, plant diversity, stand dynamics, and …