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Injectable, Magnetic Plum Pudding Hydrogel Composites For Controlled Pulsatile Drug Release, Danielle Maitland 2014 McMaster University

Injectable, Magnetic Plum Pudding Hydrogel Composites For Controlled Pulsatile Drug Release, Danielle Maitland

Open Access Dissertations and Theses

Injectable, in-situ gelling magnetic plum pudding hydrogel composites were fabricated by entrapping superparamagnetic iron oxide nanoparticles (SPIONs) and thermosensitive N-isopropylacrylamide (NIPAM)-co–N-isopropylmethacrylamide (NIPMAM) microgels in a pNIPAM-hydrazide/carbohydrate-aldehyde hydrogel matrix. The resulting composites exhibited significant, repeatable pulsatile release of 4 kDa FITC-dextran upon exposure to an alternating magnetic field. The pulsatile release from the composites could be controlled by altering the volume phase transition temperatures of the microgel particles (with VPTTs over 37°C corresponding to improved pulsatile release) and changing the microgel content of the composite (with higher microgel content corresponding to higher pulsatile release). By changing the ...


Reductive Depolymerization Of Kraft Lignin For Chemicals And Fuels Using Formic Acid As A In-Situ Hydrogen Source, Shanhua Huang 2014 Western University

Reductive Depolymerization Of Kraft Lignin For Chemicals And Fuels Using Formic Acid As A In-Situ Hydrogen Source, Shanhua Huang

University of Western Ontario - Electronic Thesis and Dissertation Repository

In this thesis work, formic acid (FA) proved to be an effective in-situ hydrogen donor for the reductive de-polymerization of kraft lignin (KL). At the optimum conditions without catalysts, i.e., 300 oC, 1 h, 18.6 wt.% substrate concentration, 50/50 (v/v) water-ethanol medium at a FA-to-lignin mass ratio of 0.7, KL (Mw ~10,000 g/mol) was effectively de-polymerized, producing de-polymerized lignin (DL, Mw 1, 270 g/mol) at a yield of ~90 wt.% and wt.% yield of solid residue (SR). The effects of heterogeneous catalysts on KL reductive de-polymerization in 50/50 ...


An Economic Analysis Of Small-Scale Biodiesel Production: Implementation Of Ethyl Ester Production In A Job Shop Setting, Scott Haase, Benjamin Craig 2014 Minnesota State University, Mankato

An Economic Analysis Of Small-Scale Biodiesel Production: Implementation Of Ethyl Ester Production In A Job Shop Setting, Scott Haase, Benjamin Craig

Journal of Undergraduate Research at Minnesota State University, Mankato

Biodiesel is becoming a demanded consumer automotive alternative fuel used in diesel vehicles today. An emerging trend is toward small-scale biodiesel production performed by the final consumer. A limited source of commercially available production systems exists and has resulted in many systems being designed and built by the user. Preliminary research conducted by the authors has shown biodiesel to be the least-cost alternative to petroleum diesel after as few as 8 months of system use. This study examines the economic viability of building and producing biodiesel using a small-scale production system versus buying consumer petroleum diesel. During production, measurements were ...


Factors Affecting Bed Agglomeration In Bubbling Fludized Bed Biomass Boilers, Alejandro Montes 2014 Western University

Factors Affecting Bed Agglomeration In Bubbling Fludized Bed Biomass Boilers, Alejandro Montes

University of Western Ontario - Electronic Thesis and Dissertation Repository

Agglomeration of bed materials at high temperature is one of the most important and challenging problems for fluidized-bed biomass boilers for thermal/power generation. Inorganic alkali components from the fuel can be problematic as they form low-melting alkali compounds. In the present study, the critical amount of liquid (molten ash in real biomass boiler operations) that would result in severe bed agglomeration and defluidization was studied in two small pilot-scales bubbling fluidized bed (BFB) rigs, one operated at room temperature using glycerol-water to simulate molten ash and the other operated at elevated temperatures using low melting-point salt (KOH) to simulate ...


Solid-Phase Extraction As Sample Preparation For Bioassay-Based Micropollutant Quantification, Chen Feng 2014 Western University

Solid-Phase Extraction As Sample Preparation For Bioassay-Based Micropollutant Quantification, Chen Feng

University of Western Ontario - Electronic Thesis and Dissertation Repository

Solid phase extraction (SPE) using chemically bonded silica particles or small particles of an organic polymer resin, is being studied extensively for extraction of polar or non-polar compounds from various water matrices. This study focused on the evaluation of the performance of three commercial cartridges belonging to three different groups: reversed-phase, mixed-mode anion exchanger and mixed-mode cation exchanger. In the first stage of research, the performance of three cartridges was compared by extracting four antibiotics with different physic-chemical properties from water samples. The results obtained from column sorption experiments were plotted into breakthrough curves and batch equilibrium experiments results were ...


Tissue Engineering Scaffolds With Enhanced Oxygen Delivery Using A Cyclodextrin Inclusion Complex, Tierney GB Deluzio 2014 Western University

Tissue Engineering Scaffolds With Enhanced Oxygen Delivery Using A Cyclodextrin Inclusion Complex, Tierney Gb Deluzio

University of Western Ontario - Electronic Thesis and Dissertation Repository

The development of a strategy to improve oxygen delivery to cells seeded on scaffolds is essential for the success of tissue engineering applications. The focus of this work was to explore the application of cyclodextrin inclusion complexes (CD:ICs) with perfluorocarbons as oxygen carriers. CD:ICs were prepared from alpha-cyclodextrin and perfluoroperhydrophenanthrene via co-precipitation, paste mixing, and dry mixing complexation techniques. Characterization indicated that paste mixing at a 2:1 host:guest ratio was the most effective method for complexation between the parent molecules. The CD:ICs were then successfully incorporated in 3D fibrous mats via electrospinning with poly(carbonate ...


Surfactant Assisted Dispersion Of Single-Walled Carbon Nanotubes In Polyvinylpyrrolidone Solutions, Tennison Yu 2014 Western University

Surfactant Assisted Dispersion Of Single-Walled Carbon Nanotubes In Polyvinylpyrrolidone Solutions, Tennison Yu

University of Western Ontario - Electronic Thesis and Dissertation Repository

Obtaining stable aqueous dispersions is one of the main challenges hindering a widespread and effective use of single-walled carbon nanotubes (SWNT) in many applications. Although it has been recognized that their versatility makes them an extremely attractive material, the unique molecular structure that gives SWNTs their unmatched electronic, mechanical, and thermal properties is also responsible for strong van der Waals interactions. This, combined with extremely high aspect ratios and flexibility, causes SWNTs to adhere strongly into tightly bundled ropes. In these bundles, SWNTs are not as useful as their linearized unbundled equivalents. Thus, in order to take advantage of their ...


Laser-Assisted Surface Modification Of Hybrid Hydrogels To Prevent Bacterial Contamination And Protein Fouling, Guobang Huang 2014 Western University

Laser-Assisted Surface Modification Of Hybrid Hydrogels To Prevent Bacterial Contamination And Protein Fouling, Guobang Huang

University of Western Ontario - Electronic Thesis and Dissertation Repository

Silicone hydrogels have been extensively studied in the fields of contact lenses, tissue engineering, and drug delivery due to their good biocompatibility, high oxygen permeability, and proper light transmission. However, their applications in biomedical devices are limited by protein adsorption and bacterial contamination because of the hydrophobic surface of silicone, which will cause more irreversible protein adsorption. Several physical methods can be applied to create a hydrophilic surface on hydrogels, such as spin coating, physical vapor deposition, dip coating, drop casting, etc. Compared to the conventional methods, the matrix assisted pulsed laser evaporation (MAPLE) is suitable to produce biopolymer/polymer ...


Enhancement Of Biohydrogen Production From Co-Fermentation Of Glucose, Starch, And Cellulose, Medhavi Gupta 2014 Western University

Enhancement Of Biohydrogen Production From Co-Fermentation Of Glucose, Starch, And Cellulose, Medhavi Gupta

University of Western Ontario - Electronic Thesis and Dissertation Repository

The aim of this study was to assess the synergistic effects of co-fermentation of glucose, starch, and cellulose using anaerobic digester sludge (ADS) on the biohydrogen (H2) production and the associated microbial communities. At initial pH of 5.5 and mesophilic temperature of 37 ºC, the H2 yields were greater by an average of 27 ± 4% in all the different co-substrate conditions compared to the mono-substrate conditions, which affirmed that co-fermentation of different substrates improved the hydrogen potential. The sensitivity of mesophilic ADS to a temperature shock was also investigated. Unacclimatized mesophilic ADS responded well to a temperature ...


Au@Tio2 Nanocomposites For The Catalytic Degradation Of Methyl Orange And Methylene Blue: An Electron Relay Effect, Mohammad Mansoob Khan Dr, J. Lee, M. H. Cho 2014 SelectedWorks

Au@Tio2 Nanocomposites For The Catalytic Degradation Of Methyl Orange And Methylene Blue: An Electron Relay Effect, Mohammad Mansoob Khan Dr, J. Lee, M. H. Cho

Dr. Mohammad Mansoob Khan

Au@TiO2 nanocomposites were used for the catalytic degradation of methyl orange and methylene blue by NaBH4. A detail pathway for step by step reduction, oxidation and complete mineralization of intermediates into the respective end-products was established by UV-vis spectroscopy, chemical oxygen demand, ion chromatography and cyclic voltammetry (CV). CV studies confirmed that the dyes were reduced and oxidized to the end-products by NaBH4 in the presence of Au@TiO2 nanocomposites and O2•, •OH and HO2• radicals generated in-situ. Results suggest that Au@TiO2 nanocomposites not only assist in the decolorization of dyes, but also promote their complete mineralization into ...


Highly Visible Light Active Ag@Zno Nanocomposites Synthesized By Gel-Combustion Route, Mohammad Mansoob Khan Dr, S. A. Ansari, J. Lee, M. H. Cho 2014 SelectedWorks

Highly Visible Light Active Ag@Zno Nanocomposites Synthesized By Gel-Combustion Route, Mohammad Mansoob Khan Dr, S. A. Ansari, J. Lee, M. H. Cho

Dr. Mohammad Mansoob Khan

Highly visible light active 1% and 3% Ag@ZnO nanocomposites were synthesized via a gel combustion route using citric acid as a fuel. The formation of the nanocomposites with enhanced properties was confirmed using a range of characterization techniques, photocatalysis and photoelectrochemical studies. Compared to the pristine ZnO nanoparticles, the Ag@ZnO nanocomposites exhibited enhanced visible light photocatalytic activity for the degradation of methylene blue and photoelectrochemical response. A mechanism was proposed to account for the photocatalytic activities of the Ag@ZnO nanocomposite that showed the surface plasmon resonance (SPR) of Ag is an effective way of enhancing the visible ...


Does A Plastron Improve Heat Transfer?, Madani A. Khan, Jeffrey Alston, Andrew Guenthner 2014 California Polytechnic State University

Does A Plastron Improve Heat Transfer?, Madani A. Khan, Jeffrey Alston, Andrew Guenthner

STEM Teacher and Researcher (STAR) Program Posters

Superamphiphobic surfaces strongly repel both water and oils. In this work, aluminum coupons are processed by sanding with various grit of sand paper to impart microscale roughness. Subsequent submersion of the aluminum substrate in boiling water grows nanoscale grass-like structures. The oxide layer of Al is slightly soluble in water. During a fast diffusion/equilibrium, Al2O3 nanograss grows on the surface. A low energy coating is then deposited on the surface. The micro and nanoscale features create re-entrant structures that trap air enabling contact liquid to be in a Cassie-Baxter state. Superamphiphobicity of the samples were confirmed ...


Production Of Recombinant Human Coagulation Factor Ix By Transgenic Pig, Weijie Xu 2014 University of Nebraska - Lincoln

Production Of Recombinant Human Coagulation Factor Ix By Transgenic Pig, Weijie Xu

Chemical & Biomolecular Engineering Theses, Dissertations, & Student Research

Hemophilia B is the congenital bleeding disorder caused by deficiency in functional coagulation factor IX (FIX) and about 28,000 patients worldwide in 2012. And current treatment is restricted to protein-replacement therapy, which required FIX concentrates for patients’ life-time. Approximately 1 billion units FIX were consumed in 2012. However, still about 70-80% patients, mostly in developing countries, received inadequate or no treatment because of the unavailable and/or unaffordable FIX concentrates. Considering safety reasons, e.g. transmission of blood-borne diseases, the recombinant human FIX (rFIX) is recommended other than the plasma-derived FIX. However, only one rFIX is currently available on ...


Opto-Electronic Devices With Nanoparticles And Their Assemblies, Chieu Van Nguyen 2014 University of Nebraska - Lincoln

Opto-Electronic Devices With Nanoparticles And Their Assemblies, Chieu Van Nguyen

Chemical & Biomolecular Engineering Theses, Dissertations, & Student Research

Nanotechnology is a fast growing field; engineering matters at the nano-meter scale. A key nanomaterial is nanoparticles (NPs). These sub-wavelength (< 100nm) particles provide tremendous possibilities due to their unique electrical, optical, and mechanical properties. Plethora of NPs with various chemical composition, size and shape has been synthesized. Clever designs of sub-wavelength structures enable observation of unusual properties of materials, and have led to new areas of research such as metamaterials. This dissertation describes two self-assemblies of gold nanoparticles, leading to an ultra-soft thin film and multi-functional single electron device at room temperature. First, the layer-by-layer self-assembly of 10nm Au nanoparticles and polyelectrolytes is shown to behave like a cellular-foam with modulus below 100 kPa. As a result, the composite thin film (~ 100nm) is 5 orders of magnitude softer than an equally thin typical polymer film. The thin film can be compressed reversibly to 60% strain. The extraordinarily low modulus and high compressibility are advantageous in pressure sensing applications. The unique mechanical properties of the composite film lead to development of an ultra-sensitive tactile imaging device capable of screening for breast cancer. On par with human finger sensitivity, the tactile device can detect a 5mm imbedded object up to 20mm below the surface with low background noise. The second device is based on a one-dimensional (1-D) self-directed self-assembly of Au NPs mediated by dielectric materials. Depending on the coverage density of the Au NPs assembly deposited on the device, electronic emission was observed at ultra-low bias of 40V, leading to low-power plasma generation in air at atmospheric pressure. Light emitted from the plasma is apparent to the naked eyes. Similarly, 1-D self-assembly of Au NPs mediated by iron oxide was fabricated and exhibits ferro-magnetic behavior. The multi-functional 1-D self-assembly of Au NPs has great potential in modern electronics such as solid state lighting, plasma-based nanoelectronics, and memory devices.

Adviser: Ravi F. Saraf


Study Of High Pressure Steaming On Lipid Recovery From Microalgae, Ana-Maria Aguirre 2014 Western University

Study Of High Pressure Steaming On Lipid Recovery From Microalgae, Ana-Maria Aguirre

University of Western Ontario - Electronic Thesis and Dissertation Repository

Sustainable and clean fuels are in demand due to the perceived negative effects on health and environment with current use of fossil fuels. Lipids from microalgae offer a potential approach to obtain sustainable biofuels. In this study a two step process was adopted: investigation of culture conditions to find optimal points for lipid productivity and cellulose content, followed by an investigation of microalgae disruption for lipid recovery.

In the first phase of the research the effect of culture conditions on Chlorella vulgaris biomass concentration and the ratio of lipid productivity/cellulose content were studied. Response surface methodology was applied to ...


Pharmacokinetic Characterization Of Procoagulation Proteins, Nicholas C. Vanderslice 2014 University of Nebraska - Lincoln

Pharmacokinetic Characterization Of Procoagulation Proteins, Nicholas C. Vanderslice

Chemical & Biomolecular Engineering Theses, Dissertations, & Student Research

The cessation of bleeding in mammals occurs due to a well-conserved sequence of protein activation known as the coagulation cascade. However, people who have a deficiency in one or more proteins in this cascade, whether due to genetics or blood loss, struggle to maintain hemostasis. In order to aid patients in the restoration of hemostasis, exogenous proteins are often administered in response to bleeding events. However, these proteins are limited and costly due to limited supply of donor blood available for the production of plasma-derived proteins and the high cost of mammalian cell bio-reactors required for the production of recombinant ...


Calculated Vs. Experimental Values For Volume And Surface Resistivity In Various Polymer Compounds, Megan Webster 2014 University of Tennessee, Knoxville

Calculated Vs. Experimental Values For Volume And Surface Resistivity In Various Polymer Compounds, Megan Webster

Pursuit - The Journal of Undergraduate Research at the University of Tennessee

Versatile due to their resistance to high stress environments including but not limited to extreme temperature, pressure, and stress, polymers additionally have many uses in electrical applications wherein antistatic or conductive properties are preferential, i.e. conductive seals, oil pipeline spheres, and gaskets, to name a few. Being a complex material, many factors may affect the electrical resistivity of a given polymer compound including type and amount of carbon black, type of rubber, cure time and temperature, and dispersion, amongst other factors. External conditions such as relative humidity and temperature also play key roles. This paper will analyze five different ...


Energy Economy In Extractive Metallurgy, Fathi Habashi 2014 SelectedWorks

Energy Economy In Extractive Metallurgy, Fathi Habashi

Fathi Habashi

Fuel, heat, and electricity are costly items in metallurgical processes and should be used with great efficiency to decrease production costs. To this end, the recent trend in metallurgical plants is focused towards the following goals: • Increased use of heat recovery systems • Increased use of oxygen instead of air • Increased use of direct heating systems • Improved equipment design• Improved process design • Improved methods of operation • Improved process design • Improved methods of operation • Attempts to economize energy in the aluminum industry industry


Developent Of A Phospholipid Encapsulation Process For Quantum Dots To Be Used In Biologic Applications, Logan Grimes 2014 California Polytechnic State University

Developent Of A Phospholipid Encapsulation Process For Quantum Dots To Be Used In Biologic Applications, Logan Grimes

Master's Theses and Project Reports

The American Cancer Society predicts that 1,665,540 people will be diagnosed with cancer, and 585,720 people will die from cancer in 2014. One of the most common types of cancer in the United States is skin cancer. Melanoma alone is predicted to account for 10,000 of the cancer related deaths in 2014. As a highly mobile and aggressive form of cancer, melanoma is difficult to fight once it has metastasized through the body. Early detection in such varieties of cancer is critical in improving survival rates in afflicted patients. Present methods of detection rely on visual ...


Mechanism Of Insulin Aggregation: Applied To Alzheimer's Disease, Milos Atz 2014 University of Connecticut

Mechanism Of Insulin Aggregation: Applied To Alzheimer's Disease, Milos Atz

Honors Scholar Theses

Alzheimer’s disease, a debilitating neurodegenerative illness, is caused by the irreversible aggregation of beta-amyloid proteins in the brain. In Alzheimer’s brains, the protein can become disfigured, causing it to aggregate into long, insoluble fibers that deposit on brain tissue. Studying the aggregation mechanisms of amyloid proteins can lead to a deeper understanding of the progression of Alzheimer’s disease and possibly point towards a potential cure or treatment for the disease. Heat induced aggregation of insulin provides a model system to study the aggregation of amyloidogenic proteins. This study investigates the early stages of heat induced insulin aggregation ...


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