Magnetically induced drug release can be used as a site-specific, minimally invasive pharmaceutical treatment. Its purpose is to increase the efficacy of drug therapies to diseased or damaged tissue and to decrease the amount of unnecessary damage to healthy, surrounding tissue. To prove the concept of drug release by a magnetic field, this study focused on the release of a fluorescent molecule from magnetic polymeric nanoparticle composites (PNCs) via induction of an alternating current (AC) magnetic field. Fluorescent magnetic PNCs used were 250 ?m or less in size, and were made of poly(methyl methacrylate) (PMMA) containing either the magnetic material magnetite nanoparticles or cobalt nanoparticles, and the fluorescent dye fluorescein isothiocyanate (FITC). Characterization of the composites included transmission electron microscopy (TEM) and scanning electron microscopy (SEM) for size and morphology, fluorescent microscopy for fluorescent images, elemental analysis for iron and cobalt content, and superconducting quantum interference device (SQUID) magnetometer readings for saturation magnetization measurements and field profiles of each particle type. Magnetic release of FITC from the composites was induced by applying an AC magnetic field to the PNCs in phosphate buffered saline (PBS) at various frequencies in the range of 44-430 Hz at the corresponding voltage of 15-123 V, magnetic field strength of approximately 465 G and current of 11 A. The PNCs were exposed to the magnetic field for various amounts of time ranging from 5 minutes to 3 hours and at temperatures of 4°C, 22°C, and 43°C. For each experiment, a control sample that was not exposed to the magnetic field was also tested for release. Fluorescence released was measured using a fluorospectrometer following filtration and sample dilution. The investigations demonstrated that the release of FITC was not significantly dependent on the frequency of the magnetic field, the experimental duration, nor the presence of the AC magnetic field. The study demonstrated, however, that greater release of FITC was dependent on higher temperatures and that magnetite-PNCs released more FITC than cobalt-PNCs. This research potentially leads the way to the biological applications of in-vitro and in-vivo studies of magnetically induced, controlled drug release from magnetic polymeric structures.

Nearly every continent has species of crawfish that inhabit wetlands or are near coastal areas where petroleum and other oils are produced, transported, and accidentally released. Most crawfish cannot tolerate polluted water. Thus, they could serve as biomonitors of fossil fuel, biofuel, and other oil releases and assess potential negative impacts such oils have on wetland and coastal ecosystems. The objectives of this study were to estimate the acute toxicity of three oils to juvenile crawfish and determine if toxicity was due to poisoning or interference with oxygen transfer across the gills. Juvenile crawfish (Procambarus clarkii) were tested for acute toxicity (96-h) using South Louisiana crude, peanut and mineral oils. Pairs of randomized tanks, with ten crawfish per tank or twenty per treatment concentration, were used in each experiment. Temperature (22°C±1) and standard water quality parameters were maintained constant based on ASTM protocols. The acute toxicity of South Louisiana crude oil was compared with peanut oil, a representative of biofuels and similar biologically-based oils, and mineral oil, which has a higher molecular weight and represents the heavier components of crude oil and biofuels. Two sets of experiments showed crude oil is acutely toxic to juvenile crawfish from 50 to 100 mg/L, with 84 mg/L being the LC50 (median lethal concentration at 96-h). Peanut oil acute toxicity, identified by another pair of experiments, was approximately one order-of-magnitude lower (LC50 = 600 mg/L) than crude oil. The heavier mineral oil produced another order-of-magnitude lower mortality, with the LC50 exceeding 10,000 mg/L. The gills of crawfish exposed to crude oil did not appear to be coated with hydrocarbons and the mortality observed is putatively due to poisoning, Peanut oil mortality appeared to be due to poisoning plus smothering, whereas mineral oil mortality appeared to be due primarily to smothering. This work suggests possible engineering techniques to reduce the toxic effects of oils and points to toxicity considerations of biofuels. Additional laboratory and field-based studies using juvenile crawfish are needed to provide understanding of the mechanisms of acute and chronic toxicity by hydrocarbon and biologically-based oils in sensitive wetland and coastal ecosystems. Key words: crawfish, crude oil, biofuel, toxicity, ecology, engineering

A system for the direct production of white sugar from clarified sugar cane juice in a raw sugar factory has been developed at the Audubon Sugar Institute. This Direct White Sugar Production (DWiSP) system employs a series of columns packed with adsorbent media. Activated carbon is used in the first column(s) as a filter and bulk decolorizer. Ion exchange resins are then used to remove ash and remaining color. Batch testing was performed in order to determine equilibrium parameters. An analytical model was utilized in conjunction with column loading tests to determine dynamic characteristics of the carbon adsorber for use in determining design parameters. Ion exchange columns were investigated to determine deashing and decolorization properties. The use of hydrogen peroxide pretreatment was also investigated. Chemical regeneration of carbon was also investigated. Batch test indicated a decrease in the carbon's adsorptive capacity when the feed was pretreated. Column tests indicated that residence time has a significant effect on carbon column performance and film mass transfer was related to superficial velocity as is described in previous work. The ion exchange system performed consistently over seven cycles and was able to produce a low color, low ash product for approximately 15 bed volumes, after which exhaustion set in rapidly. Exhaustion was indicated by a sharp increase in conductivity of the final column product. Evaluation of a New Regeneration Process (NRP) for chemical regeneration of carbon showed it to be effective in returning the carbon to 70-85% of its virgin capacity. The NRP solution was also compared to a regenerant solution of sodium hydroxide. The NRP solution was twice as effective as a 2% sodium hydroxide solution, but costs more than twice as much.

The need to reduce the United States dependence on foreign oil has never been greater. In the past decade emphasis has been placed on developing new and/or improved means to procure clean renewable energy. Liquefaction, which was developed for coal conversion over a century ago is one of these areas. Liquefaction used for biomass conversions to bio-oils is grouped under the thermochemical conversion (TCC) area of energy conversion methods along with gasification and pyrolysis. This thesis discusses liquefaction experiments conducted using varieties of Louisiana biomass feedstocks. Dairy manure collected from the Louisiana State University Dairy Farm in Baton Rouge, was the main feedstock studied using various temperatures (250-350)°C and catalysts (Na2CO3, NaOH, and K2CO3) to determine optimum operating conditions for these two parameters. A bench scale 300 ml pressure vessel was used to conduct hydrothermal liquefaction (HTL) experiments. The HTL process yielded oil products (hydrocarbons) for all experiments. Temperature was found to have a significant influence (P <0.05) on bio-oil energy content. One gram of sodium carbonate coupled with a processing temperature of 350°C is recommended as the optimum processing conditions for dairy manure in this study. However, the catalyst amount and type had had no significant effect (P > 0.05) on bio-oil when compared to no catalyst. Minimal differences were found when statistically comparing the types and quantities of catalysts with one another. Temperatures of at least 350°C are recommended for conversion of dairy manure to oil; although higher temperature trials were not conducted due to pressure vessel limitations. All additional feedstocks tested (tallowseed, switchgrass, pine sawdust, and poultry litter) yielded heating values that were comparable or higher than the 34.7MJ kg-1 reported as the maximum heating value for dairy manure oils. Oil yields are reported in the range of 20-33% on an organic basis.

The objective of this study is to characterize the photobiological and thermal effects of UVA light on cell cultures. While near-ultraviolet light has been widely used to photoactivate fluorophores and caged compounds in cells, little is known of the long-term biological effects of this light. UVA (320-400nm) photoactivating light has been used for studying fast kinetic processes and is now being employed in higher doses to target longer duration phenomena (e.g. gene expression and silencing). Photoexposure experiments using 365nm light will examine how longer duration and increased UV doses affect photoactivation cell studies. Apoptotic and cellular injury assays have been used to determine the nature and threshold of this light-induced effect. UVA light sources of low and high intensity have been used for light doses up to 23.85 J/cm2. HeLa cells exposed to staurosporine, high intensity UVA, and equivalent UVB served as positive UVA-induced and UVB-induced apoptotic controls. Cells were stained with annexin V-Cy5 and propidium iodide for apoptosis analysis with a conventional flow cytometer. Cell cultures at lower densities had higher percentages of apoptotic and dead cells, and were also more susceptible to UVA damage than more dense cell seedings. The dose to induce apoptosis and death in 50% of the cells (dose1/2) was determined for two different commercially available UVA light sources: 7.6 J/cm2 for the GreenSpot photocuring system and 2.52 J/cm2 for the BlakRay lamp. No significant cellular responses were found for doses below 1.6 J/cm2 from the GreenSpot light source. A temperature control and measurement system was used to determine direct heating from the UVA sources and also the effect that cooling culture dishes has on minimizing cell damage. Photoduration was also found to be significant in determining UVA photoactivation doses. Together, these results show that many of these parameters are important for optimizing photobiological studies.

Alternative energy production through biomass gasification produces combustible gases, such as carbon monoxide, hydrogen, and methane. These gases can be used for generation of direct heat, electricity, or liquid fuels through the Fischer Tropsch process. However, a major limitation of the overall process is the purity of the generated synthesis gas. The tars and particulates generated in the gasification process constitute a major impediment to the commercial use of this technology because they may condense on valves, fittings, and therefore, hinder the smooth running of an engine. This research was aimed at developing a gas characterization and testing protocol, and the removal of tars and particulates in the synthesis gas generated from a downdraft biomass gasifier. The tars and particulates sampling and analysis was based on a modified EPA Method 5. The protocol modifications were done to suit the specific characteristics of the gasifier and the generated synthesis gas. This test protocol involves gravimetric analysis of the particulates retained on a high temperature glass-fiber filter and tars dissolved in a series of solvent bottles (with acetone). Baseline studies using woodchips produced tar and particulates concentrations of 1.63 g/Nm3 +0.46 and 3.84 g/Nm3+1.16 respectively; while pine pellets produced 0.85 g/Nm3 +0.16 and 4.75 g/Nm3 + 0.07 respectively. Downstream treatment using a catalytic bed of calcined dolomite, albermale proprietary catalyst, and bag filter were designed for cleaning the raw gas. An investigation of the dolomite bed temperature on gas cleaning showed that at temperature above 750oC, about 90% and 50% of the tar and particulate were respectively removed; while at 650oC about 60% and 40% of tar and particulate were removed respectively. A combined use of the proprietary catalyst at 250oC and bag filter reduced the tars and particulate concentration by approximately 90% and 98% respectively. The exiting gas was also characterized for its heating value and found to be approximately 3.38 MJ/Nm3 +0.39 and 3.67 MJ/Nm3 +0.09 for woodchips and pine pellets respectively.

The goal of this work was to assist in overcoming the most important bottlenecks in the biodiesel production chain: to improve the biodiesel production process (oil extraction and esterification) using advanced microwave technologies from traditional and alternative feedstock; and identify the important characteristics of an alternative, high oil yield crop (TT). Dielectric properties of two feedstocks, soybean and rice bran were measured in presence of several solvents at different ratios, temperature and frequency. Results indicated that dielectric properties are ratio, temperature, frequency and solvent type dependent. Quasi-linear relationship using second order logarithmic transformation of the data provided a reliable estimator for the behavior of dielectric properties of the feedstocks used. Results assisted in further selection of appropriate solvent, mixing ratio, temperature and frequency for the design and develop of a continuous microwave assisted extraction (CMAE) system for oil (laboratory and pilot scale). Yield of oil extracted increased with extraction temperature and time for both feedstocks. Oil yield high as 15% for soybean and 16% for rice bran was extracted at laboratory scale. At pilot scale, 18.6% oil for soybean and 19.5% for rice bran respectively was extracted, with oil quality meeting the ASTM requirements for vegetable oil. The continuous microwave system was further used for biodiesel transesterification reaction. High conversion rates (96.7-99.4%) were achieved at the reaction times (1, 5 and 10 min) and temperature (50 and 73°C) studied, with the required specifications for biodiesel quality. Quality analysis on oil extracted from TT kernel, provided evidence that after 12 weeks of storage in controlled atmosphere no differences in quality was observed compared to low cost air storage. Moreover, late harvested seeds did not show major degradation in oil quality necessary for biodiesel production when compared with early harvested seeds.

Improved oral delivery of vitamins and antioxidants via food, beverages or supplements can be achieved by encapsulation of the bioactive component in biodegradable and biocompatible colloidal and nanoparticle systems. Mucoadhesive chitosan/Poly (D, L-lactide-co-glycolide) particles were investigated as a means to control the release of bioactive compounds such as vitamin E in the gastrointestinal (GI) tract. Chitosan/PLGA particles with entrapped alpha-tocopherol at different initial loadings were synthesized by emulsion evaporation method, compared against PLGA particles in terms of their physical properties, stability, and gastrointestinal release profiles. Chi/PLGA particles of 250 ± 8.9 nm with a zeta potential of 61 ± 3.1 mV, and 0.232 polydispersity were formed at 16% theoretical initial loading (with respect to PLGA) and 0.6 w/v% chitosan. Chitosan/PLGA particles were stable below pH 5 and above pH 8; at low pHs particles were positively charged whereas at high pHs they had a negative zeta potential. Particles precipitated between pH 5 and 8. Stability of the particles as function of time revealed that PLGA particles remained stable with an average particle size, zeta-potential and PDI of 120 nm, − 65 mV, 0.3, respectively, over a day under all gastrointestinal conditions, except pH 1.5, where the particle system approached point of zero charge and aggregated. Similarly, Chitosan/PLGA particles aggregated around neutral pHs, but were well dispersed at pH 1.5. The particle release kinetics in simulated gastric and intestinal environments for different initial alpha-tocopherol loadings was studied. Faster alpha-tocopherol release occurred for 8% initial loading under gastric conditions compared to 16% and 24% alpha-tocopherol initial loadings. Initial loading had no significant effect on the intestinal release of αT. The PLGA particle systems also exhibited a faster release rate compared to Chitosan/PLGA particles mostly due to smaller size. 40% alpha-tocopherol was released within 2 hours under gastric conditions, and 54 % released after 5 days under intestinal conditions, from PLGA particles. In comparison, Chi/PLGA particles released only 20 % under gastric and 58 % under intestinal conditions. Hence, Chi/PLGA were found superior in increasing the residence time of alpha-tocopherol in the GI tract which theoretically could be associated with improved αT bioavailability.

Development of liquid biofuels has entered a new phase of large scale pilot demonstrations. A number of plants in operation or under construction face the engineering challenges of creating a viable plant design, scaling up, and optimizing various unit operations. It is well-known that separation technologies account for 50-70% of both capital and operating costs. Processes vary in terms of selection of unit operations; however, solid-liquid separations are likely to be a major contributor to the overall project costs. A typical process for ethanol production from biomass includes several solid-liquid separation steps. The nature of biomass derived materials makes it either difficult or uneconomical to accomplish complete separation in a single step. Material balance models were developed for two bagasse-to-ethanol processes utilizing alkaline-pretreatment, and applied to evaluate the sensitivities of the process yields to separation performance. This aided in setting realistic efficiency targets for solid-liquid separations. Results from material balance calculations revealed that 10% of solid feed material can be lost to liquid streams, with an equivalent process yield reduction. Both filtration and sedimentation processes were found to have low separation efficiencies, due to small particle sizes, low density, and the fibrous nature of bagasse. Because of low concentrations of suspended solids in the liquid stream (0.1-0.15%), recovery of solids by centrifugation may require high capital and operating costs. The efficiency of a dissolved air flotation process (DAF) for recovery of suspended solids from liquid stream derived from dilute-ammonia pretreatment process was investigated. DAF was evaluated for suspended solids recovery from the liquid stream obtained from alkaline pretreated cane bagasse. A continuous bench scale DAF clarifier was constructed and tested. The effect of additives at various chemical addition rates, air-to-solids ratios and hydraulic loadings on the DAF process was determined. Small quantities of lime were found to enhance flotation of particles and minimize the use of flocculants. Recoveries of suspended solids were in the range of 50-57% and were accompanied by a greater volume reduction than could be achieved by conventional sedimentation. The DAF process effectively concentrated solids from 0.1% in the feed material to 8-9% in the floated fraction.

Currently, a majority of the worlds energy needs are met through use of fossil fuels, petroleum, coal and natural gas. The depletion of petroleum reserves, rising and extremely volatile crude oil prices, and environmental concerns have led to search for renewable and environmentally friendly fuels. The ultimate goal of this research was to develop, test and optimize a batch microwave system using traditional and alternate non-food feedstocks. Microwave assisted extraction (MAE) of oil from conventional feedstocks (soybeans and rice bran) and an alternative feedstock (Chinese tallow tree (CTT) seeds) was carried out. The study concluded that MAE of oil is a rapid, efficient and effective method of extracting oil from the feedstocks as compared to conventional extraction techniques. Maximum yields of 17.3%, 17.2% and 32.5%, representing ~ 95% of total recoverable oil, were obtained for soybean, rice bran and CTT seeds by microwave extraction in 20 mins. This compares extremely favorably to the hours of processing required by conventional methods. The enhanced extraction is due to the specific interaction of the microwave field with the solvent-feedstock matrix, where higher temperature and pressure gradients develop at the microscopic level, leading to enhanced mass transfer coefficients. Optimization of transesterification reaction parameters was carried out as the second objective of the research. Refined soybean and rice bran oil were used as biodiesel feedstocks. Two alcohols, methanol and ethanol, were tested in this study. Sodium hydroxide was the catalyst and the reactions were carried out in presence of microwaves. By use of microwaves, the reaction times were drastically reduced, and >95% conversions could be achieved for very small catalyst concentration (< 0.2%) which reflected in easier separation of byproducts from the biodiesel phase. The enhanced biodiesel production reaction rates occurred due to two main mechanisms: (1) molecular mixing of the polar alcohol molecules with the oil in the presence of the oscillating electric field component and (2) volumetric heating effect of microwaves, eliminating the time for transient conductive/ convective heat transfer in the mixture. Quality analysis of biodiesel according to ASTM standards was performed and the samples were found to meet the necessary specifications.