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Full-Text Articles in Engineering

Evaluation Of The Performance Of A Downward Flow Inclined Gravity Settler For Algae Dewatering, Dustin D. Bowden Jan 2015

Evaluation Of The Performance Of A Downward Flow Inclined Gravity Settler For Algae Dewatering, Dustin D. Bowden

ETD Archive

With recent concerns over the environmental implications of burning fossil fuels coupled with the depletion of fossil fuel reserves an alternative source of energy isneeded. Algae derived biofuels may be an effective replacement for transportation fuels as they are carbon neutral and have a high area productivity. Algae is superior to terrestrial plants as a biofuel source due to its high oil productivity and efficiency along with the fact that it will not displace food production. Currently the largest obstacle to the implementation of commercial algae to biofuel processes is algae dewatering. The separation of algae from water is difficult ...


Determining The Transport Enhancement Of Sodium Fluorescein In Mechanically-Loaded Canine Tibia, Andrew Joseph Zak Jan 2015

Determining The Transport Enhancement Of Sodium Fluorescein In Mechanically-Loaded Canine Tibia, Andrew Joseph Zak

ETD Archive

Quantitative research concerning the impact of mechanical loading on the transport properties of bone has several critical applications. One such application is the effect of a microgravity environment, where the lack of mechanical forces on bone has been shown to negatively impact both growth and repair. A method has been developed in our lab that can potentially allow for the measurement of the effective permeability of large molecules (i.e., 300-15,000 Da in size) in bone tissue under both unloaded and mechanically loaded conditions. In proof-of-concept experiments, previous students have measured the effective diffusivity of the model solute, sodium ...


Time And Temperature Dependent Surface Tension Measurements Of Responsive Protein-Based Polymer Surfactant Solutions, Hakan Celik Jan 2015

Time And Temperature Dependent Surface Tension Measurements Of Responsive Protein-Based Polymer Surfactant Solutions, Hakan Celik

ETD Archive

A three-armed star elastin-like polypeptide (ELP-foldon) has thermoreversible character which exhibits phase separation above a transition temperature (Tt) in physiologic salt concentrations. At lower salt concentration, the ELP-foldon behaves like a thermoresponsive surfactant, exhibiting micelle formation above its Tt. The purpose of this study is characterize the surfactant behavior of the ELP-foldon at air-liquid interface by measuring the surface tension. The surface tension is measured as a function of time for different ELP concentrations from 10 nM to 50 ℗æM and over range of temperatures from 25 to 35 ℗¿ using the axisymmetric drop shape analysis (ADSA). The ADSA is a ...


A Psa Process For An Oxygen Concentrator, Aaron A. Moran Jan 2014

A Psa Process For An Oxygen Concentrator, Aaron A. Moran

ETD Archive

Oxygen is used in a variety of chemical processes and for medical purposes throughout the world. Pressure swing adsorption (PSA) has become a viable alternative to cryogenic distillation for the separation of oxygen from air with the development of advanced adsorbents like zeolites. PSA processes are inherently complex because it is a dynamic process. Efficient operation of a PSA process is necessary in order to utilize the capacity of the adsorbent as much as possible and reduce the power requirements of the process.In this thesis, a novel zeolite adsorbent was utilized in a PSA process for oxygen generation with ...


Slurry Based Coatings On Silicon Based Ceramics, Sameer K. Khaja-Abdul Jan 2008

Slurry Based Coatings On Silicon Based Ceramics, Sameer K. Khaja-Abdul

ETD Archive

The use of advanced structural ceramics, such as Si3N4 (SN282), SiC, and SiC/SiC composites, is a promising technology to accomplish the high performance goals for advanced turbine applications. These materials exhibit excellent corrosion resistance by forming a dense silica scale. However, severe degradation of the silica scale has been observed due to the presence of certain environmental species, like alkali salts and water vapors, limiting the long-term reliability of structural ceramics. Presence of water vapor in the turbine environment leads to the formation of a gaseous silicon hydroxide species (Si(OH)4) via a reaction with silica layer, SiO2 ...


Engineering Polyanhydride Microspheres For The Stabilization And Controlled Release Of Proteins , Amy Sywassink Determan Jan 2006

Engineering Polyanhydride Microspheres For The Stabilization And Controlled Release Of Proteins , Amy Sywassink Determan

Retrospective Theses and Dissertations

This work investigates the use of polyanhydride microspheres as drug delivery carriers for therapeutic proteins. The polymers investigated are poly(sebacic anhydride) and opolymers of poly[1,6-bis(p-carboxyphenoxy)hexane] (poly(CPH)) and poly(SA), 20:80 (CPH:SA), 50:50 (CPH:SA), and 80:20 (CPH:SA). The model protein bovine serum albumin (BSA) was encapsulated in poly(SA), 20:80 (CPH:SA), 50:50 (CPH:SA), and 80:20 (CPH:SA) microspheres to determine the feasibility of using polyanhydrides as protein carriers. Poly(SA) and 20:80 (CPH:SA) were found to stabilize the encapsulated BSA and were ...


Directed Growth And Selective Differentiation Of Neural Progenitor Cells Using A Synergistic Combination Of Topographical And Soluble Cues , Jennifer Behr Recknor Jan 2006

Directed Growth And Selective Differentiation Of Neural Progenitor Cells Using A Synergistic Combination Of Topographical And Soluble Cues , Jennifer Behr Recknor

Retrospective Theses and Dissertations

The purpose of this study is to develop strategies to facilitate nerve regeneration using a synergistic combination of guidance cues. We are investigating the cellular mechanisms of development using adult rat hippocampal progenitor cells (AHPCs) and have demonstrated that manipulating a combination of physical, chemical and biological cues can lead to oriented astrocyte and neural progenitor cell outgrowth and can influence progenitor cell differentiation. To provide physical guidance, micropatterned polystyrene (PS) substrates were fabricated and chemically modified with laminin. Astrocytes or AHPCs cultured on these substrates align along the grooves of the patterned surface extending highly elongated processes. To further ...


Recovery And Purification Of Recombinant Protein From Transgenic Corn By Aqueous Two-Phase Partitioning , Zhengrong Gu Jan 2006

Recovery And Purification Of Recombinant Protein From Transgenic Corn By Aqueous Two-Phase Partitioning , Zhengrong Gu

Retrospective Theses and Dissertations

Aqueous two-phase (ATP) partitioning was paired in a variety of ways to use of transgenic corn for protein expression. Systems were developed to selectively partition corn proteins from classes of potential recombinant proteins as well as the specific case of dog gastric lipase. More fundamentally, ATP partitioning was used to expand 2D gel electrophoretic characterization of protein size and pI to the third dimension of hydrophobicity with the usefulness of the method illustrated for corn extracts;ATP partitioning in polyethylene glycol (PEG)-salt systems separates proteins primarily according to their surface hydrophobicity differences. The average hydrophobicity of pH 7 extracts ...


Engineering Bioerodible Polymers With Tailored Micro/Nanostructure For Vaccine Delivery , Matthew J. Kipper Jan 2004

Engineering Bioerodible Polymers With Tailored Micro/Nanostructure For Vaccine Delivery , Matthew J. Kipper

Retrospective Theses and Dissertations

This work describes the investigation of bioerodible polyanhydrides as controlled drug delivery vehicles. The polymers studied are based on the 1,6-bis(p-carboxyphenoxy)hexane (CPH) and sebacic acid (SA) monomers. These two materials erode at vastly different rates and can be combined in random copolymers or blends to achieve tailored erosion kinetics. The hydrophobic nature of these materials offers the potential to stabilize proteins, and their mutual incompatibility and semicrystallinity provide an interesting phase behavior, which can be exploited to aid in tailoring the release kinetics. Theoretical and experimental description of the microstructure of polyanhydride copolymers reveals the details of ...


Development Of Novel Polymeric Materials For Gene Therapy And Ph-Sensitive Drug Delivery: Modeling, Synthesis, Characterization, And Analysis , Brian Curtis Anderson Jan 2002

Development Of Novel Polymeric Materials For Gene Therapy And Ph-Sensitive Drug Delivery: Modeling, Synthesis, Characterization, And Analysis , Brian Curtis Anderson

Retrospective Theses and Dissertations

The aim of this work was to obtain a fundamental understanding of drug release mechanisms from polymers that undergo thermoreversible gelation and to synthesize new polymers based on these that exhibit both pH and temperature sensitivity. Novel block and random copolymers with cationic character have been developed for drug delivery and gene therapy applications. The development of these materials began with a study of the mechanism of drug release from poly(ethylene oxide) (PEO) and poly(propylene oxide) (PPO) block copolymers. This study revealed the release rates of drugs from water-soluble hydrogels composed of the PEO-PPO-PEO block copolymer PluronicRTM F127 ...


Design Of A Bioartificial Nerve Graft , Gregory Edward Rutkowski Jan 1999

Design Of A Bioartificial Nerve Graft , Gregory Edward Rutkowski

Retrospective Theses and Dissertations

Nerve injuries complicate successful rehabilitation more than any other form of trauma because of loss of protective sensibility and tactile discrimination, denervation atrophy of muscles, and pain syndromes. While achieving full function and organ reinnervation after peripheral nerve injury is a challenge, a promising method of improving the rate and success of regeneration is the bioartificial nerve graft (BNG). The BNG developed in the laboratory consists of a porous bioresorbable tube containing cultured Schwann cells that help to direct and support nerve regeneration when used to bridge the gap between the ends of the severed nerve;To aid in the ...


The Effects Of Physiological Levels Of Intermittent Pressure On The Development Of Articular Cartilage In Vitro , Scott Edward Carver Jan 1998

The Effects Of Physiological Levels Of Intermittent Pressure On The Development Of Articular Cartilage In Vitro , Scott Edward Carver

Retrospective Theses and Dissertations

A semi-continuous perfusion system has been designed and constructed to deliver physiological levels of hydrostatic pressure to regenerating cell/polymer constructs of articular cartilage over the long term (weeks to months). Prior to being transferred to the pressurized system, equine articular chondrocytes were dynamically seeded onto nonwoven meshes of polyglycolic acid which provide the cells with a three-dimensional growth environment similar to that found in vivo. When applied in an intermittent manner, physiological pressurization at 500 psi was found to stimulate articular chondrocytes to produce regenerated constructs with greater concentrations of sulfated glycosaminoglycan compared to control (unpressurized) constructs, while the ...


Development Of A Coupled Model Of The Cardiorespiratory And Thermoregulatory Systems , Dawn Denise Downey Jan 1998

Development Of A Coupled Model Of The Cardiorespiratory And Thermoregulatory Systems , Dawn Denise Downey

Retrospective Theses and Dissertations

A model of the human body which integrates the variables involved in temperature regulation and blood gas transport within the cardiovascular and respiratory systems is presented in this dissertation. It expands upon previous work developed by the author to model the competition between skin and muscles when both require increased blood flows during exercise and/or heat stress. First, a detailed study of the control relations used to predict skin blood flow was undertaken. Four other control relations employed in the model were also examined and modified as indicated by empirical results found in literature;Several important cases were then ...


A Quantitative Estimation Of Regulation And Transport Limitations In The Human Cardiopulmonary System , Sharmista Chatterjee Jan 1997

A Quantitative Estimation Of Regulation And Transport Limitations In The Human Cardiopulmonary System , Sharmista Chatterjee

Retrospective Theses and Dissertations

The object of this dissertation is to quantitatively describe the regulation of some of the exchange processes within the human body. Conceptually this dissertation is divided into two sections. In the first section a macroscopic view was adopted to describe the overall regulation of the cardiovascular and respiratory systems. These overall system models were used as heuristic tools to gain an understanding of physiological behavior in micro-gravity. In the second section, a microscopic view was used to estimate the role played by the surfactant system of the lung in regulating the transfer of fluid across the pulmonary-capillary wall;The basis ...


Water And Electrolyte Regulation During Space Flight And Exercise , Susan Elizabeth Doty Jan 1994

Water And Electrolyte Regulation During Space Flight And Exercise , Susan Elizabeth Doty

Retrospective Theses and Dissertations

When one is exposed to microgravity, fluid which is normally pooled in the lower extremities is redistributed headward and weight bearing bones begin to demineralize due to reduced mechanical stresses. The kidney, which is the primary regulator of body fluid volume and composition, responds to the fluid shift and bone demineralization by increasing the urinary output of water, sodium, and calcium. This research involves developing a mathematical description of how water and electrolytes are internally redistributed and exchanged with the environment during space flight. Various levels of activity are also considered, since it is believed that exercise can prevent some ...


An Experimental And Theoretical Study Of Heat Transfer And Temperature Control In The Dog , James Niels Petersen Jan 1979

An Experimental And Theoretical Study Of Heat Transfer And Temperature Control In The Dog , James Niels Petersen

Retrospective Theses and Dissertations

No abstract provided.


A Mathematical Model For Human Thermoregulation , Nicholas Carl Miller Jan 1972

A Mathematical Model For Human Thermoregulation , Nicholas Carl Miller

Retrospective Theses and Dissertations

No abstract provided.