Digital Commons Network^™

Microalgae Immobilization With Filamentous Fungi: Process Development For Sustainable Food Systems, Suvro Talukdar

Theses and Dissertations--Biosystems and Agricultural Engineering

Demand for sustainable food sources has increased because of the rapid growth of the world's population.  In this study, microalgae cells of Haematococcus pluvialis were immobilized using the edible fungal strain Aspergillus awamori for potential food applications. The study investigated the impact of fungal loading, pellet geometry, and initial microalgae cell concentration on the immobilization performance and product characteristics. It was found that higher fungal loading and larger fungal pellets contributed to increased immobilization performance while increased initial microalgae concentration inhibited the process. Larger fungal pellets had decreased biomass density, which led to decreased surface concentration of immobilized microalgae but …

Fate And Transport Of Nanopesticides In Agricultural Field Plots In Central Kentucky, William D. Rud

Theses and Dissertations--Biosystems and Agricultural Engineering

Due to a growing world population, pesticide applications are necessary part to increasing agricultural production on the same arable land, but this has created environmental contamination, human toxicity, and endangerment to non-target species (i.e, honeybees, monarch butterflies) from bulk pesticide application. Nanoengineered particles or ENP are a potential solution with increased efficiency, longer duration, and enhanced stability of pesticides due to their unique formulations at smaller sizes. However, the potential long-term impact to agroecosystems is still unknown. Therefore, the goal of this project was to evaluate the fate, transport, impact, and persistence of two commercially available nanopesticides (copper hydroxide and …

Applying Hermetic Storage And Multiple Abiotic-Stressed Germinations To Actuate Desirable Effects In Wheat Phytochemistry, Food, And Biological Functionalities, Bababode Kehinde

Theses and Dissertations--Biosystems and Agricultural Engineering

Wheat is one of the most widely consumed staple foods in the world, supplying both nutritional and caloric requirements for billions of people. The rising global population and increased food demand behooves all stakeholders across the wheat supply chain to significantly increase their output and efficiency. Beyond the target for increased farm yields, dietary, nutritional, and health requirements along with their continuous supply must be satisfied with improved storage and processing schemes. Post-harvest changes in wheat can result in a significant reduction in its quality. Such losses could be qualitative and/or quantitative, impacting its physical, physiological, organoleptic, and nutritional attributes. …

Impact Of Physicochemical Characteristics And Distillation Parameters On The Biomethane Potential Of Bourbon Stillage, Danielle Hockensmith

Theses and Dissertations--Biosystems and Agricultural Engineering

Bourbon, or whiskey, production in Kentucky has been estimated to double within the next five years and an increase in the main by-product from bourbon distillation, stillage. Stillage is composed mostly of water along with the fermented grains after distillation. Stillage is expensive to dispose of and difficult to store due to the high biodegradability, posing a risk to the environment given the low pH and high chemical oxygen demand (COD). Anaerobic digestion has been identified as a potential solution for stillage valorization, but little research has been performed. Stillage from different mash bills has varying physicochemical properties, total solids …

Life Cycle Assessment Of Air Classification As A Sulfur Mitigation Technology In Pine Residue Feedstocks, Ashlee Edmonson

Theses and Dissertations--Biosystems and Agricultural Engineering

Sulfur accumulation during biofuel production is pollutive, toxic to conversion catalysts, and causes the premature breakdown of processing equipment. Air classification is an effective preprocessing technology for ash and sulfur removal from biomass feedstocks. A life cycle assessment (LCA) sought to understand the environmental impacts of implementing air classification as a sulfur-mitigation technique for pine residues. Energy demand and material balance for preprocessing were simulated using SimaPro and the Argonne National Laboratory’s GREET model, specifically focusing on comparing the global warming potential (GWP) of grid electricity versus bioelectricity scenarios. Overall, the grid electricity scenario had a GWP impact over 7 …

Nanopesticide Influence On Nitrogen Cycling In Soils, Jacob Richardson

Theses and Dissertations--Biosystems and Agricultural Engineering

Nanotechnology has several applications in the agricultural industry, as the small size of nanoparticles and high reactivity enables targeted delivery of pesticides and fertilizers to the intended crop. Copper-based nanopesticides such as Kocide, are proposed as a more efficient method for targeted pest control. Despite the potential benefits of nanopesticides, little is known regarding the transport and implications of nanopesticides under long-term inundation conditions often found in downstream wetlands. Specifically, the impact of nanopesticides on microbial nitrogen processes in wetland environments remains unknown. Therefore, this thesis explores the impact of nanopesticides, specifically Kocide, on microbial nitrogen cycles in agricultural and …

Fate And Transport Of Emerging Contaminants Entering, Leaving, And Flowing Past Wastewater Treatment Plants In Central Kentucky, Kyra Sigler

Theses and Dissertations--Biosystems and Agricultural Engineering

Per- and polyfluoroalkyl substances (PFAS) and neonicotinoid insecticides are two classes of emerging contaminants that have been recently detected in many environmental compartments. Both have been associated with negative impacts on humans and the environment. Wastewater treatment plants (WWTPs) have been identified as likely hotspots for introduction of these contaminants into the environment. Thus, the aim of this study was to investigate the occurrence of PFAS and neonicotinoids in two WWTPs in Central Kentucky. Polar organic chemical integrative samplers (POCIS) were deployed in WWTP influent and effluent and placed upstream and downstream of the effluent mixing zone (EMZ) for two …

A Process Intensification Approach To Improve Volatile Fatty Acids Production, Extraction, And Valorization, Can Liu

Theses and Dissertations--Biosystems and Agricultural Engineering

Anaerobic digestion (AD) is a widely used biowaste conversion method. Recent studies have explored arrested methanogenesis as an alternative approach to leverage existing AD facilities and produce volatile fatty acids (VFAs) instead of biogas. VFAs have been recognized as precursors for a range of value-added chemicals and bioproducts. Arrested methanogenesis involves inducing acidic fermentation by halting the AD process before methanogenesis. It has been found that higher organic loading and thermophilic conditions enhance VFA accumulation and stabilize the acidic fermentation (AF) system.

Brewer's spent grain (BSG), a significant by-product of the brewing industry, was employed as the feedstock for VFA …

Improving Indoor Arenas For The Equine Industry, Staci Mcgill

Theses and Dissertations--Biosystems and Agricultural Engineering

Equine indoor arenas are a unique infrastructure investment found at equine farms and facilities. They are semi-indoor structures for exercising horses, exhibiting skills during competitive events, and other equine related activities. These spaces do not always include mechanical ventilation or stirring fans and occupancy by horses and humans can be sporadic and inconsistent, which creates a challenging space for understanding and predicting airflow. Typically, indoor arenas have a sand-based footing over which the horse travels. The impact of the hooves can cause dust to become a concern within the facilities. Environmental concerns within these facilities (temperature, respirable dust, moisture, and …

Unmanned Aircraft Systems For Precision Meteorology: An Analysis Of Gnss Position Measurement Error And Embedded Sensor Development, Karla S. Ladino

Theses and Dissertations--Biosystems and Agricultural Engineering

The overarching objective of this research was to enhance our comprehension of the three-dimensional precision of meteorological measurements obtained using small unmanned aircraft systems (UAS). Two complimentary experiments were conducted to achieve this objective.

The first experiment entailed the development and implementation of a system to determine the global navigation satellite system (GNSS) position accuracy on a UAS platform. This system was utilized to assess the static and dynamic accuracy of L1 and L1/L2 GNSS receivers in real-time kinematic (RTK) and non-RTK fix modes. Adjusted two-sample t-tests revealed significant differences in horizontal and vertical error between RTK and non-RTK receivers …

Densification Of Hemp Floral Biomass Pre And Post-Extraction: Determination Of Pellet Physical Characteristics, Gary Lopez

Theses and Dissertations--Biosystems and Agricultural Engineering

The production of cannabidiol (CBD) from the floral material of Cannabis sativa L.is of great interest to the hemp industry. The low bulk density oh hemp floral material presents challenges in terms of storage and handling. To improve handling and storage characteristics, both intact (pre-extraction) and supercritical CO₂ extracted hemp floral materials were pelletized. Intact floral material (BaOx) was passed through a hammer mill with a 5 mm screen; while, extracted floral material (Hawaiian Haze) was ball milled through a 60 mesh (250 microns) prior to extraction. Pelletization was conducted using a 3.7 kW pilot scale flat ring …