The Louisiana Gulf Coast is losing land at an alarming rate for a combination of reasons. At the same time carbon dioxide is accumulating in the atmosphere and the oceans by the increased burning of fossil fuels. Therefore, bioengineered oyster dominated artificial reefs have been developed in an effort to mitigate erosion while storing carbon in the oyster shells. These reefs support the growth of a native oyster species, Crassostrea virginica, which are considered ecological engineers and serve to improve water quality, protect coastal wetlands, capture and store carbon, and enhance the economy. Evaluation of test pieces showed the addition of biological material to encourage significantly higher oyster recruitment (p=0.002). Locations lower in the water column and further from shore also had higher recruitment rates (p=0.0004, p=0.05 respectively). The test on carbon storage potential showed a carbon payback period of ~ 6-8 months and a 500% payback after thirty months. A map of potential emplacement sites (oyster zone) was also created to aid in selecting future project locations. Preliminary engineering design was done in order to optimize the geometry of these structures and the emplacement techniques. Future work in this area should include monitoring and documentation of full-scale project emplacements and oyster growth patterns. This project has revealed the potential for the use of a sustainable, ecologically beneficial, and cost effective method of shoreline protection with the added benefit of long-term carbon storage.

Eleven metal coagulants and one polyelectrolyte were assessed on their suitability for assisting a dissolved air flotation (DAF) system in treating poultry processing wastewater. The DAF unit was designed to maximize the microbubble production by varying the pressure, temperature, hydraulic retention time, and air flow parameters. The maximum microbubble flow from the designed system produced 30 mL of air per L of water. This value was considered low compared to other systems, but attempts to increase the microbubble volume in the current system beyond this value resulted in the coalescing of microbubbles due to turbulent conditions. Jar tests were used to identify the best coagulant available and were based on the removal efficiency of total suspended solids (TSS) and volatile suspended solids (VSS). These results were compared to increases in water clarity measured by optical density. Preliminary tests determined that a combination of 800 mg/L of ferric chloride and 900 mg/L of Floccin 1115 would provide the best treatment by removing at least 98% of the TSS and 97% of the VSS while providing a 97% increase in water clarity. Final flotation tests displayed that the flocculated particles could be carried to the surface with 40% recycle ratio of the DAF. The resulting supernatant indicated 94.7% increase in clarity (± 1.4%), 97.3% reduction in TSS (± 0.5%), 96.6% reduction in VSS (± 1.1 %), 91% reduction in COD (chemical oxygen demand), and nearly 100% removal of FOGs (fats, oils, and greases). Despite the high removal efficiencies, flotation was found not to be critically necessary for treatment because the high concentration of coagulants caused settling of the flocs to occur just as rapidly. The combination of these two coagulants was also determined impractical, costing nearly twice the current treatment costs of the processing plant. Due to limited alkalinity and excess phosphate in the wastewater, overdosing was a potential issue but could easily be addressed in future work.

PLGA (polylactic-co-glycolic acid) nanoparticles containing the hydrophobic antifungal Itraconazole (ITZ) were developed to address the need for more efficient means of treating fungal infections. PLGA-ITZ nanoparticles were synthesized using an oil-in-water emulsion evaporation method. The nanoparticles morphology (TEM), size and size distribution, zeta potential (DLS), encapsulation efficiency (UV-VIS), release profile, and antifungal activity were characterized. The blank NPs and loaded PLGA-ITZ NPs were spherical with diameters of 201±5 nm, 232±1 nm and 223±36 nm at 0%, 12.5% and 25% loadings, respectively. All synthesized particles measured a negative zeta potential ranging from -28 to -33 mV. The maximum encapsulation efficiency of ITZ was ~96% at 12.5% w/w theoretical loading. ITZ release showed an initial burst followed by a gradual release profile, with 75% ITZ released over 5 days. PLGA-ITZ nanoparticles inhibited Aspergillus flavus fungal growth more efficiently than free and emulsified ITZ. Quantitative fluorescence experiments performed with a GFP-expressing A. flavus verified that the PLGA-ITZ NPs had superior inhibitory activity at lower ITZ concentrations compared to free and emulsified ITZ drug formulations. PLGA-ITZ nanoparticles (232 nm) completely inhibited Aspergillus flavus growth over 11 days at 0.3 mg/ml ITZ, a concentration 100x less than free and emulsified ITZ. In nanoparticle uptake studies, 203 nm fluorescent PLGA nanoparticles containing coumarin-6 were seen associating with fungal cell surfaces and internalizing efficiently, while 1206 nm particle uptake was sporadic. Quantitative fluorescence experiments of PLGA-ITZ NPs of 232 nm, 630 nm, and 1060 nm showed inhibitory differences at the lowest ITZ concentration of 0.003 mg/ml, and no differences at higher concentrations. The PLGA-ITZ nanoparticle system is envisioned to increase bioavailability of ITZ by improving its aqueous solubility, controlling its release over time and especially increasing antifungal penetration at the cellular level by efficient nanoparticle uptake by cells, thereby elevating antifungal efficacy.

Over application of phosphorus and the loss of ammonia-nitrogen to runoff and volatilization have resulted in the buildup of phosphorus in agricultural top soils around the world, and especially in the United States. Over the past few decades, raising livestock has trended towards the development of the Confined Animal Feeding Operations (CAFOs) which produce large volumes of wastes that need to be treated before being land applied. Nutrient treatment systems have typically focused on one nutrient singularly: either nitrogen or phosphorus. In order to develop a total nutrient system a phosphorus and nitrogen system had to be developed and evaluated before combining them to represent a complete system. A pilot phosphorus treatment system consisting of hydrated lime precipitation treatment was evaluated on both an alligator ranch and a dairy parlor research station. An 88% reduction of total phosphorus in the alligator raising pen wastewater was achieved and a 99% reduction of total phosphorus was achieved in the dairy parlor wastewater. The system added $0.00197/gal-year when treating the alligator wastewater and added $0.00033 /gal-year when treating the dairy parlor wastewater. A pilot nitrogen treatment system consisting of a nitrification reactor utilizing rice hulls as the bacterial growth media was developed at the lab scale before eventually being implemented in a field scale nutrient treatment system. The lab scale results showed 50% ammonia oxidation occurring at 30-hrs, 48-hrs, and 48-hrs after commencement of the three experiments. They were encouraging enough to continue on to total nutrient treatment system development. A total nutrient treatment system was designed to both remove phosphorus and to keep usable nitrogen in the wastewater. A 99% reduction in total phosphorus was achieved in a matter of hours and 50% oxidation of the total ammonia was achieved in 5-days and 4-days of treatment in each field-trial. The total treatment system had the potential to save $2,500 annually in nitrogen kept in solution and not lost to volatilization and added $1.78 /cow-year in phosphorus recovery through the hydrated lime treatment.

Ten different types of feedstocks available in Louisiana were assessed for their suitability to produce SYNGAS in a down-draft biomass gasifier. The feedstocks tested for this research include: pine pellets, hardwood pellets, cypress mulch, pine bark nuggets, corn stover pellets, switchgrass pellets, sugarcane bagasse pellets, dairy manure pellets, and poultry litter pellets. The feedstocks were first analyzed for volatile & ash content, high heating value, moisture, and mass density. Feedstocks that met the analytical criteria and available in a form that is suitable for the down-draft gasifier at LSU were tested for gasification. The temperature profile within the gasifier and exiting oxygen concentrations were monitored for each of the tested feedstocks. Results indicated that pine and hardwood pellets had moisture contents of 6.04 ± 0.5% and 5.39 ± 0.22%, respectively, which was considered optimum for gasification. However, corn pellets had higher moisture content (13.3 ± 0.44%) and had to be dried to 7 ± 1% moisture for successful gasification. Results also indicated that low ash and high volatile solids contents were critical for gasification. Pine pellets and hardwood pellets had the least ash (0.37 ± 0.1% and 0.85 ± 0.2%) and highest volatile solids (99.62 ± 0.1% and 99.14 ± 0.5%), therefore, performed best during gasification runs. Poultry litter and dairy manure pellets had more than 39% ± 0.8% ash and less than 62 ± 0.8% volatile solids, which made them unsuitable for gasification. Four feedstocks (Alfalfa, switchgrass, bagasse, and corn) had moderate levels (12.16% - 3.28 %) of ash contents, with alfalfa having the highest ash content. Out of these feedstocks with moderate ash contents, alfalfa pellets failed to gasify consistently. Cypress mulch and pine bark nuggets, although had the necessary properties for gasification (low ash, high volatile solids, acceptable high heating values, and low moisture), the mass density was too low and required continuous feeding. Although these feedstocks gasified, the frequent valve openings and closings and constantly varying volumes of biomass inside the gasifier caused major temperature fluctuations. The actual suitability of these feedstocks can be tested either after densification (pelletization) or by incorporating an automated feeding system for the gasifier. The dairy manure pellets, switchgrass pellets, bagasse, and chicken litter pellets could not be tested in the gasifier due to unavailability in these pellets in the market in bulk volumes. The in-house hammermill and pelletmill were not found to be undersized for large scale production of pellets. The exiting SYNGAS (SYNthesis GAS) was passed through adjacent sampling unit for quantification of tars and particulates gravimetrically. Of the 5 feedstocks that were tested for gasification, syngas from pine pellets had very high tar and particulate concentration, as high as 0.80399 ± 0.183 g/Nm3 and 4.06377 ± 0.721 g/Nm3 respectively. However, the same values were lowered to 0.26 g/Nm3 (tars) and 1.2 g/Nm3 (particulates) after passing the gas through a tar cracking catalyst bed maintained at 250˚C

As costs have decreased and both computational complexity and robustness have increased, the use of autonomous vehicles in real-world environments has increased dramatically. The development of a fleet of autonomous surface vehicles able to coordinate their actions through communications provides a significant tool for numerous water-based applications such as the reduction of predatory birds on aquaculture ponds, tracking of pollutant gradients, and water quality mapping applications. A fleet of three autonomous surface vehicles (ASVs) was developed using the best characteristics from earlier designs. Each vehicle is a dual-pontoon, dual-paddlewheel design powered by batteries recharged using a vehicle-mounted solar array that produces a peak output of 30 Watts. The control system consists of two microcontrollers: a TS-7260 ARM-based microcontroller board that handles high-level functions such as navigation, the collection, storage, and analysis of data, and communication; and a BASIC Atom Pro that handles motor control. A major design goal was modularity. This allows for quick and easy field repairs and upgrades. Communication is essential for fleet success. The dual-microcontroller system in these ASVs has two levels of communication. Intra-ASV communications are handled via serial connections between the ARM and the BASIC Atom Pro on each ASV, whereas inter-ASV communications use XBee Radio Modules with an approximate range of 300 meters. Through the use of relaying, we have an effective range of 600 meters across the fleet of three ASVs. Longer-ranges are possible with other radios. It is desirable to know at all times where the ASV is both with respect to the other ASVs in the fleet and to the data being collected. By collecting and storing GPS coordinates on a regular basis and especially when a sample is taken, we have the ability to map the data being collected. Maps were constructed demonstrating the potential 50-80% reduction in birds. The development of the fleet of ASVs provides a novel, inexpensive, highly configurable, mobile platform for experimentation. Future research possibilities exist of significant importance including: gradient tracking of pollutants for both point source and non-point source pollutants; coastal applications including salinity mapping and bathymetry mapping; ecosystem monitoring; biosecurity applications; and others.

The majority of the worlds energy needs are currently met through the use of fossil fuels. The possible depletion of fossil fuel resources and environmental concerns has prompted the search for alternative renewable and environmentally friendly energy resources. The goal of this research was to develop a microwave-assisted dilute ammonia pretreatment technology for the conversion of sweet sorghum into ethanol. Conversion of biomass into ethanol requires a pretreatment step to open up the structure and decouple the cellulose, and hemicellulose and lignin in the biomass. In the first study, sorghum bagasse was pretreated with 28% ammonium hydroxide, and water at a ratio of 1:0.5:8 at different temperatures for 1h using microwave. Biomass treated at 160 oC for 1h with dilute ammonia removed 46% of the lignin while retaining 90% cellulose and 73% hemicelluloses. Evaluation of microwave pretreatment of sorghum biomass based on enzymatic hydrolysis and fermentation results was carried out also. The best ethanol yields among all different pretreatment conditions were 22±1.1g/100 g dry biomass using the 1-2mm particle size under 130 oC for 1h. The raw bagasse averaged 10±0.9g ethanol/100 g dry biomass. The concentrations of glycerol, organic acids, and furfurals were below the inhibitory level. A third study used Tween 80 in the pretreatment stage, which was supposed to enhance the performance of the pretreatment. Sorghum bagasse was pretreated with a combination of ammonium hydroxide and Tween 80 for 45min at 130oC. For 3% Tween 80 concentration, the glucose obtained from the hydrolysis was 38.1 g per 100 g dry biomass, compared to 33.2 g per 100 g dry biomass for control. The ethanol yield was 19 g per 100 g dry biomass, a nearly 19% improvement over the control. The final study was designed to test the hypothesis that by using microwave for pretreatment, the water requirements be dramatically reduced by single soaking and draining of the biomass prior to the pretreatment. The pretreatment was performed by mixing sorghum fibers and 28% ammonia hydroxide solution at a ratio of 1:0.5 and heating the mixture to 130oC for 1 h. Ethanol yields were 17 g/100 g dry biomass.

The objective of this study was to synthesize and characterize antimicrobial, silver nanoparticles based self-assembling monolayer coatings, for use on chronic indwelling medical devices. The coatings are comprised of novel biomass mediated silver nano particles (SNP) that are biocompatible, highly concentrated, highly pure, cost-effective, polydispersed and compatible for use with existing chronic indwelling medical devices. The HPC SNPs were functionalized with an azide functional group and covalently bound to titanium substrates via ¨Dclick¡¬ chemistry.

Water management represents an essential component in all agricultural activities, where significant improvements can be achieved through the implementation of field measuring devices and irrigation scheduling models. The methods that integrate these tools may be based on information regarding the soil, crop, and weather. Evapotranspiration (ET) is one of the most important components of the soil water-balance used in modeling. A number of estimation methods have been developed to determine Reference Evapotranspiration (ETo) under various types of weather conditions. In this research, an analysis was conducted between different ETo estimation methods and ETo calculated from soil water content measurements and a soil-water budget, in Northeast Louisiana during the 2010 sweetpotato growing season. Similarly, the standardize ASCE Penman-Monteith equation was then compared to ETo equations using limited weather inputs. Additionally, a Sweetpotato Irrigation Scheduler (SPIS) based on a simple soil-water balance approach was developed to improve irrigation scheduling using weather, crop, and soil data. The models predictions were validated, for the critical first 30 Days after Transplanting (DAT) and for the entire growing season, against field data obtained from soil water content probes. A previously developed phenology-driven Bayesian belief network model was used to establish the timing and depth of irrigation. Some difficulties where found during the assessment of ETo and the simulation of the soil-water content under unsaturated soil and dry weather conditions. These circumstances reduced the capacity of the soil to move water appropriately, slowing down some of the processes involved in the soil-water budget, causing a misrepresentation by the ETo equations and the irrigation scheduling model.

The goal of this study was to design and test a pilot scale process for biodiesel production using advanced microwave technology and develop a numerical model for investigating various parameters affecting this process. Dielectric properties of materials play a major role in microwave design of a process. The dielectric properties (dielectric constant ε and dielectric loss ε) of biodiesel precursors: soybean oil, alcohols and catalyst and their different mixtures were measured at four different temperatures (30°C, 45°C, 60°C and 75°C) and in the frequency range of 154 MHz to 4.5 GHz. Results indicate that the microwave dielectric properties of almost all components depend on both temperature and frequency. Addition of catalyst changed the properties of solvent due to the strong ionic nature. A scaled up version of a continuous microwave transesterification process was designed, built and tested. Experimental parameters were set based on previous laboratory scale results. Experiments were performed in a well controlled continuous pilot scale microwave reactor at temperatures of 60°C and 75°C and processing times of 5 to 15 minutes. Microwave power required to achieve the temperature of 60°C was 4000W and for 75°C was 4700W. Ethanol was used as a solvent with NaOH as a catalyst (< 0.2% by weight of oil). The conversion obtained was >99% for all experimental conditions. The final objective was to develop a basic numerical model of continuous electromagnetic heating of biodiesel precursors. A finite element model was built using COMSOL Multiphysics 4.2 software. High frequency electromagnetic problem was coupled with the non-isothermal flow problem. The model was tested for the two different power levels. The electric field, electromagnetic power flow and temperature profiles were studied. Resulting temperature profiles were verified by comparing to the experimental data. The presented study assists in understanding microwave heating application for biodiesel production. The dielectric property analysis gives a clear picture of interaction of biodiesel components with microwave irradiation, numerical model aids in understanding temperature distribution while experiments validate the results. This study can be applied to optimize the microwave assisted continuous biodiesel production process.