This research details laboratory assessment of bacterial hydrophobicity, variations in bacterial adhesion properties with growth and extended starvation as well as extension of this assay to colloidal hydrophobicity measurement. Hydrophobicity is an integral component of surface interactions and has been studied extensively for its role in a number of engineering...
Nickel or nickel alloys are common materials used in under bump metallization (UBM) in flip chip technology. Nickel is used because of its slow reaction rate with tin-based solder at
elevated temperatures. However, nickel is ferromagnetic at room temperature, hence cannot be easily deposited with magnetron sputtering. In this study,...
There has been much controversy in recent years over the leaching of chemicals from plastic water bottles. In this study, two of the most common plastics used in water bottles, polyethylene terphthalate (PETE) and polycarbonate (PC) were studied. The leaching of the chemical bisphenol-A (BPA) from polycarbonate (Nalgene ™, Camelback...
The conventional advection-dispersion equation cannot adequately describe all processes driving
solute transport in heterogeneous systems. This dissertation focuses on the individual influences
of both chemical (Chapter 2) and physical processes (Chapters 3 and 4) which affect
solute transport. In Chapter 2 we analyzed uranium transport in natural sediment using the...
Recent advances in nanocrystalline materials production are expected to impact the development of next generation low-cost and/or high efficiency solar cells. For example, semiconductor nanocrystal inks are used to lower the fabrication cost of the absorber layers of the solar cells. In addition, some quantum confined nanocrystals display electron-hole pair...
There is significant interest in utilizing microalgae as a source for biofuels. Diatoms are a class of single-celled microalgae which make silica cell walls and require dissolved silicon as a substrate for cell division. Manipulation of soluble silicon delivery to the culture offers a route to control cell cycle and...
Currently, the technologies used to separate lignocellulosic biomass into its component parts (cellulose, hemicellulose, and lignin) and enzymatically hydrolyze the cellulose to glucose for conversion to ethanol could be improved economically and in terms of efficiency. A major impediment to utilizing the biomass is the presence of residual lignin. The...
A direct numerical simulation of advection-diffusion in a sinusoidal tube was
carried out using the commercial finite-volume code STAR-CD. The Reynolds
numbers varied from Re = 0.1 to Re = 14.5. At the larger Reynolds numbers,
steady-state eddies formed in the diverging sections and significantly influenced
the macroscale dispersion. Long...
Microreactors offer high rates of heat transfer able to intensify highly endothermic biomass reforming reactions in supercritical water. In this study, two continuous flow microreactor configurations were used to gasify biomass constituents in supercritical water. The first reactor configuration was a micro diameter stainless steel or Hastelloy tube (508 µm...
Sulfur content in fuel is an increasingly important environmental concern. A
commonly used method for the removal of sulfur bearing species from fuel is
through hydrodesulphurization. However, due to the implementation of Ultra-Low
Diesel Sulfur (ULDS), deeper desulphurization techniques must be explored. In this
study, a single phase oxidative desulphurization...
Cryoprotectants (CPAs) such as glycerol and dimethyl sulfoxide (DMSO) are commonly used during cryopreservation of cell based therapeutics. Although these additives are beneficial during freezing, it is often desirable to remove them before infusion into a patient. Currently, the most common method for CPA removal is by centrifugation. This method...
There is an urgent need to lower the concentration of sulfur in diesel fuels. Growing concern over environmental effects caused by burning sulfur-containing diesel has led the world to higher standards in fuel refinement. Because of these lower standards, many techniques have been researched to remove sulfur containing compounds or...
Researchers around the world use various solution-based deposition techniques to deposit thin films with multiple layers that typically require multiple rounds of deposition. Some such techniques include successive ionic layer adsorption and reaction (SILAR), and layer-by-layer (LBL) deposition.
One of the main issues with deposition of these types of films...
The various solution-based processes, spin coating, inkjet printing, microreactor assisted nanoparticle deposition (MANDTM) and spin-successive ionic layer absorption and reaction (Spin-SILAR) were used to demonstrate thin film electronics and anti-reflective coatings. Several aspects of thin film transistors (TFTs) were tested including a range of temperatures, annealing atmosphere, and deposition methods....
The adsorption of natural organic matter (NOM) to the surfaces of natural colloids
and engineered nanoparticles is known to strongly influence, and in some cases control,
their surface properties and aggregation behavior. As a result, the understanding of
nanoparticle fate, transport and toxicity in natural systems must include a fundamental...
The capability of Pluronic® F68 to stabilize human recombinant Factor VIII in solution was
assessed using zeta potential measurements. Hemophilia A is a genetic disorder in which the
body is missing Factor VIII (FVIII) from the blood coagulation cascade. The pharmaceutical
industry developed recombinant Factor VIII (rFVIII), the largest cloned...
This dissertation explores the physiology and gene expression of the ammonia-oxidizing bacterium Nitrosomonas europaea in surface-associated bacterial communities, or biofilms. Biofilms of N. europaea were cultivated in drip flow reactors for several weeks and gene expression microarrays were used to detect 240 genes differentially expressed between the mature biofilms and...
This research investigates the physiological and transcriptional responses of Nitrosomonas europaea when exposed to chlorinated aromatic compounds and heavy metals under varying environmental conditions. It was found that transcriptional responses of identified sentinel genes correlate well with nitrification inhibition. Sorption of metals to biomass was also investigated and found not...
The primary goal of this thesis is to synthesize titanium dioxide nanorods using a continuous flow microreactor. Titania powder, one of the most important particulate materials is used for many purposes owing to its excellent optical properties of a high refractive index leading to high hiding power and whiteness of...
Atomic Layer Deposition (ALD) is a promising technique for the production of
biologically safe, wear resistant and corrosion protective coatings for orthopedic
applications. In this work, the impact of coating thickness and surface preparation on the
hardness (H), elastic modulus (E), wear resistance, and delamination of ALD Al2O3 films
is...