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A Rapid Method For Measuring Feces Ammonia-Nitrogen And Carbon Dioxide-Carbon Emissions And Decomposition Rate Constants, Jiyul Chang, David E. Clay, Sharon A. Clay, Michelle K. Ohrtman Jul 2017

A Rapid Method For Measuring Feces Ammonia-Nitrogen And Carbon Dioxide-Carbon Emissions And Decomposition Rate Constants, Jiyul Chang, David E. Clay, Sharon A. Clay, Michelle K. Ohrtman

Agronomy, Horticulture and Plant Science Faculty Publications

A rapid approach is needed for determining the eff ectiveness of precision conservation on soil health as evaluated using CO2 and NH3 emissions. Th is study demonstrated an approach for calculating CO2–C and NH3–N emissions and associated rate constants when feces were applied to bare soil or soil + vegetation. In addition, point CO2–C emission measurements were compared with near continuous measurements. The CO2–C emissions were measured at 2 h intervals over 20 d, whereas ammonia volatilization was measured three times daily for 7 d. Total CO2–C emissions …


Activated Carbon Preparation And Modification For Adsorption, Yuhe Cao Jan 2017

Activated Carbon Preparation And Modification For Adsorption, Yuhe Cao

Electronic Theses and Dissertations

Butanol is considered a promising, infrastructure-compatible biofuel. Butanol has a higher energy content than ethanol and can be used in conventional gas engines without modifications. Unfortunately, the fermentation pathway for butanol production is restricted by its toxicity to the microbial strains used in the process. Butanol is toxic to the microbes, and this can slow fermentation rates and reduce butanol yields. Gas stripping technology can efficiently remove butanol from the fermentation broth as it is produced, thereby decreasing its inhibitory effects. Traditional butanol separation heavily depends on the energy intensive distillation method. One of the main issues in acetone-butanol-ethanol fermentation …


Lignin Transformation And Characterization Of Pyrolytic Products, Eric Amo Boakye Jan 2017

Lignin Transformation And Characterization Of Pyrolytic Products, Eric Amo Boakye

Electronic Theses and Dissertations

Lignocellulosic materials derived from plants have the ability to serve as feedstocks in place of depleting petroleum and coal for production of fuels and chemicals. Lignin forms about 30% of lignocellulosic material, and is the second most abundant non-fossil organic carbon source in the biosphere. However, it is often treated as waste or, in some instances, burned to supply energy. Developing an efficient and environmentally benign method to convert lignin to high value-added aromatic monomers (e.g., guaiacol, vanillin, acetovanillone, and eugenol) for synthesis of polymers is of interest. Mineral bases, such as NaOH and CsOH, or supported-metal catalysts (Pt, Ru, …


Development Of Heterogeneous Catalysts For Upgrading Biomass Pyrolysis Bio-Oils Into Advanced Biofuels, Shouyun Cheng Jan 2017

Development Of Heterogeneous Catalysts For Upgrading Biomass Pyrolysis Bio-Oils Into Advanced Biofuels, Shouyun Cheng

Electronic Theses and Dissertations

The massive consumption of fossil fuels and associated environmental issues result in an increased interest in alternative resources such as biofuels. The renewable biofuels can be upgraded from bio-oils that are derived from biomass pyrolysis. Catalytic cracking and hydrodeoxygenation (HDO) are two most promising bio-oil upgrading techniques for biofuel production. Heterogeneous catalysts are essential for upgrading bio-oil into hydrocarbon biofuel. Although some progresses have been made, the cost and effectiveness of catalysts still remain challenges. The main objective of this study was to develop efficient heterogeneous catalysts for upgrading bio-oils into advanced hydrocarbon biofuel with low costs. In catalytic cracking, …


Impacts Of Landscape Position And Nitrogen Fertilizer On Soils, Carbon And Nitrogen Leaching, And Greenhouse Gas Fluxes From Switchgrass Production In South Dakota, Liming Lai Jan 2017

Impacts Of Landscape Position And Nitrogen Fertilizer On Soils, Carbon And Nitrogen Leaching, And Greenhouse Gas Fluxes From Switchgrass Production In South Dakota, Liming Lai

Electronic Theses and Dissertations

Switchgrass (Panicum virgatum L.) production for biofuels has potential economic values. It can also improve soil properties and perform better under marginal lands than the other major biomass crops. However, little is known about its potential ecological impacts assessed in terms of soils, water, and air quality in the northern Great Plains region of United States of America. The objectives of this study were to (i) evaluate the impacts of nitrogen fertilization rate (N rate) and landscape position on soil pH, soil organic carbon (SOC), total nitrogen (TN), bulk density (ρb), and phosphorus (P) in switchgrass field; (ii) assess …


Evaluation Of Woodchip Bioreactor Denitrification Kinetics, Abdoul Aziz Kouanda Jan 2017

Evaluation Of Woodchip Bioreactor Denitrification Kinetics, Abdoul Aziz Kouanda

Electronic Theses and Dissertations

Agricultural subsurface drainage is a water management practice used to remove excess water in poorly drained soil. The use of fertilizers combined with subsurface drainage practice affects negatively surface water quality due to nutrient loss. Woodchip bioreactors have previously been used as a technology for removing nitrate from agricultural subsurface drainage. Understanding the mechanism that governs nitrate removal in woodchip bioreactors is crucial for field bioreactor design and application. The objective of this project is to determine woodchip bioreactor denitrification kinetics parameters under different operating conditions including hydraulic retention time, temperature and influent nitrate concentrations. Laboratory column experiments were conducted …


Relationship Of The Fractal And Chemical Characteristics Of Self-Assembled Natural Organic Matter, Dennis K. Gibson Jan 2017

Relationship Of The Fractal And Chemical Characteristics Of Self-Assembled Natural Organic Matter, Dennis K. Gibson

Electronic Theses and Dissertations

Natural Organic Matter (NOM) is a heterogeneous mixture formed by the degradation of organic substances during early diagenesis in surficial environments. It has been shown that the interaction of the components that comprise this mixture has a significant impact on its microbial mineralization to CO2. The extent of NOM selfassembly is emerging as an important factor in understanding its role in the global geochemical carbon cycle, and it is beginning to appear that it may be more important than the chemical composition of a sample. The overall goal of this research is to establish NOM’s self-assembled “architecture” and …