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Full-Text Articles in Engineering

Adaption Of Catechol And Reversible Addition-Fragmentation Chain-Transfer (Raft) Chemistries For Water-Based Applications, Olabode Oyeneye Dec 2017

Adaption Of Catechol And Reversible Addition-Fragmentation Chain-Transfer (Raft) Chemistries For Water-Based Applications, Olabode Oyeneye

Electronic Thesis and Dissertation Repository

Incorporating the binding chemistry of catechol functionality with RAFT chemistry offers a facile and simplified approach for developing a suite of new 2D and 3D hybrid materials with tailored morphologies. Leveraging both chemistries by synthesizing catechol-end functionalized RAFT agents and catechol-containing monomeric species for RAFT (co)polymerization, this dissertation examined a new series of advanced materials that were designed for water-based applications including model flocculants, thermoresponsive hydrogels, adsorbents and underwater adhesives.

To prepare the RAFT agents, novel trithiocarbonates with several catechol end R groups (as postpolymerization anchors) were synthesized that differ in their carbonyl α-substituents (Dopa-CTAs). These materials were evaluated for …


Fabrication And Modification Of Titania Nanotube Arrays For Harvesting Solar Energy And Drug Delivery Applications, Ahmed El Ruby Abdel Rahman Mohamed Dec 2017

Fabrication And Modification Of Titania Nanotube Arrays For Harvesting Solar Energy And Drug Delivery Applications, Ahmed El Ruby Abdel Rahman Mohamed

Electronic Thesis and Dissertation Repository

The fast diminishing of fossil fuels in the near future, as well as the global warming caused by increasing greenhouse gases have motivated the urgent quest to develop advanced materials as cost-effective photoanodes for solar light harvesting and many other photocatalytic applications. Recently, titania nanotube arrays (TNTAs) fabricated by anodization process has attracted great interest due to their excellent properties such as: high surface area, vertically oriented, highly organized, one-dimensional, nanotubular structure, photoactivity, chemical stability and biocompatibility. This unique combination of excellent properties makes TNTAs an excellent photoanode for solar light harvesting. However, the relatively wide band gap energy of …


Study Of Motion Of Agglomerates Through A Fluidized Bed, Muhammad Owais Iqbal Bhatti Dec 2017

Study Of Motion Of Agglomerates Through A Fluidized Bed, Muhammad Owais Iqbal Bhatti

Electronic Thesis and Dissertation Repository

Formation of agglomerates in Fluid CokersTM can cause operating problems, such as excessive shed fouling, which can lead to premature unit shut down. Better understanding of how agglomerates move through a fluidized bed can help improve the design and operation of Fluid CokersTM and minimize the risk of agglomerates reaching regions where they cause problems.

To identify key factors in agglomerates motion in a fluidized bed, a new two-dimensional (2D) Radioactive Particle Tracking (RPT) method was developed which tracks model agglomerates motion. In conjunction, a tribo-electric method was used to determine bubble flow distribution in the fluidized bed. …


Synthesis Of Vo2 Nanomaterials Using Green Solvents For Thermochromic Window Coatings, Hanna Qin Dec 2017

Synthesis Of Vo2 Nanomaterials Using Green Solvents For Thermochromic Window Coatings, Hanna Qin

Electronic Thesis and Dissertation Repository

Progress in the development of energy-efficient coatings has led to recent investigations of smart windows with the ability to control heat and light. Of particular interest for this dissertation is the fabrication of vanadium dioxide (VO2) thermochromic nanomaterials using an environmentally friendly approach with good performance for optical switching. Tungsten (W) doped VO2/GO (graphene oxide) hybrids were successfully prepared using a one-step hydrothermal method. At 2 at. % doping, VO2 nanotubes were successfully synthesized with tunable phase transition temperatures (Tc) achieved as low as 42oC. In addition, various experimental parameters including …


Hydrodeoxygenation Of Anisole In A Novel Externally Agitated Reactor, Brett Pomeroy Dec 2017

Hydrodeoxygenation Of Anisole In A Novel Externally Agitated Reactor, Brett Pomeroy

Electronic Thesis and Dissertation Repository

Bio-oil upgrading via hydrodeoxygenation (HDO) was investigated using anisole, a model compound, in a novel Externally Agitated (EA) reactor which is expected to enhance gas-liquid-solid mixing. Operating conditions were established based on anisole HDO with 10 wt.% Ni on silica, γ-alumina, and δ-alumina while varying temperatures between 160 to 280oC, and reaction times between 30 – 90 minutes. Mild temperatures of 220oC and 45 minutes for reaction time with γ-alumina were selected for subsequent work since γ-alumina demonstrated the highest HDO activity. HDO was then investigated with varying Ni-Cu and Ni loadings. Despite the improved reducibility …


Hydrothermal Decarboxylation Of Fatty Acids And Their Derivatives For Liquid Transportation Fuels, Md Zakir Hossain Nov 2017

Hydrothermal Decarboxylation Of Fatty Acids And Their Derivatives For Liquid Transportation Fuels, Md Zakir Hossain

Electronic Thesis and Dissertation Repository

Due to the depletion of fossil fuel reserves, renewable resources are required to produce tomorrow’s fuel range hydrocarbons. This thesis focuses on the hydrothermal decarboxylation of fatty acids and their derivatives derived from renewable sources. These are required for liquid transportation fuels which have similar properties to conventional fuels. Detailed catalytic studies were performed for the decarboxylation of oleic acid as a model compound and corn distiller’s oil (CDO) as a real feedstock. Commercial activated carbon and laboratory prepared Ni-Al2O3, MgO-Al2O3, Mo-Al2O3 catalysts were also examined as catalysts. Fatty …


Effects Of Lignin As A Stabilizer Or Antioxidant In Polyolefins, Afsana S. Kabir Aug 2017

Effects Of Lignin As A Stabilizer Or Antioxidant In Polyolefins, Afsana S. Kabir

Electronic Thesis and Dissertation Repository

Lignin, a major component of biomass, is an attractive alternative to hindered phenol-based antioxidants for polymers due to its renewable nature and naturally occurring hindered phenolic structure. In this study, for the first time, lignin de-polymerization was explored as a promising approach to improve the reactivity of the lignin-based antioxidants for polymers (polyethylene, PE and polypropylene, PP). A proprietary hydrolytic de-polymerization process was utilized to increase the antioxidant activity of two types of technical lignin: kraft lignin, KL (a by-product from the pulp and paper industry) and hydrolysis lignin, HL (a by-product from the pre-treatment processes in cellulosic ethanol plants). …


Treatment Of Oil Sands Process-Affected Water Using Activated And Surface Modified Petroleum Coke For Organic Compounds Recovery, Hojatallah Seyedy Niasar Aug 2017

Treatment Of Oil Sands Process-Affected Water Using Activated And Surface Modified Petroleum Coke For Organic Compounds Recovery, Hojatallah Seyedy Niasar

Electronic Thesis and Dissertation Repository

Each day large volumes of oil sands process-affected water (OSPW) are being produced during the extraction of bitumen in oil sands industry in northern Alberta. OSPW contains different polyaromatic hydrocarbons which not only are the major source of toxicity in OSPW, but also create operational problems such as corrosion of the equipment during bitumen recovery process. Therefore, these compounds need to be removed prior to the recycle of the OSPW. In this research, petroleum coke (PC) as an abundant, inexpensive adsorbent was selected as an adsorbent for recovery of chemicals from OSPW. The surface area and adsorption capacity of PC …


Bacterial Cellulose Nanocrystals: Production And Application, Isabela Reiniati Aug 2017

Bacterial Cellulose Nanocrystals: Production And Application, Isabela Reiniati

Electronic Thesis and Dissertation Repository

The aims of this study were to investigate the effect of culture conditions on the production of bacterial cellulose (BC) by Komagataeibacter xylinus (K. xylinus), to assess the feasibility of tailoring the surface properties of bacterial cellulose nanocrystals (BCNs) through the culture conditions, and to use the BCNs in an aqueous system for drug adsorption application. BC fibers production improved with increased agitation rates in a stirred tank bioreactor resulting in yields of 0.54 and 1.13 g of BC per litre at agitation rates of 500 rpm and 700 rpm, respectively. Separation and purification of bacterial cellulose were achieved …


Bubble Dynamics And Bed Expansion For Single-Component And Binary Gas-Solid Fluidization Systems, Bowen Han Aug 2017

Bubble Dynamics And Bed Expansion For Single-Component And Binary Gas-Solid Fluidization Systems, Bowen Han

Electronic Thesis and Dissertation Repository

Gas-solid fluidized beds are widely used in industrial dry coal preparation to separate waste from coal (still a primarily important energy source worldwide). It is the density difference between coal and the waste that enables the separation. Experiments were carried out in a two dimensional gas-solid fluidized bed. Filtered air at room temperature was used as the fluidizing gas, while magnetite, sand (two types) and FCC catalyst particles belonging to Geldart groups A and B were used as bed particles. Image processing and Matlab were applied for bubble size and velocity measurements. Bubble properties and bed expansion in fluidized beds …


Experimental And Simulation Studies Of An Oxygen Concentration System Using Pressure/Vacuum Swing Adsorption Technique: System Miniaturization And Prototype Design, Mingfei Pan Aug 2017

Experimental And Simulation Studies Of An Oxygen Concentration System Using Pressure/Vacuum Swing Adsorption Technique: System Miniaturization And Prototype Design, Mingfei Pan

Electronic Thesis and Dissertation Repository

The miniaturization of a pressure swing adsorption (PSA) oxygen concentrator is of prime significance for portable applications. This work presented a simplified pressure/vacuum swing adsorption (PVSA) cycle with a concentrator prototype design using a deep evacuation step (-0.82 barg) instead of desorption with purge flow to improve the efficiency of oxygen production process and miniaturize the size of the concentrator. The output of the oxygen concentrator is a 50-90 vol.% enriched oxygen stream in a continuous adsorption and desorption cycle (cycle time = 75-90 s). The size of the adsorption column is 3 cm in diameter and 20 cm in …


Hydrodynamics In The Gas-Driven Inverse Liquid-Solid Fluidized Bed, Jiaqi Huang Aug 2017

Hydrodynamics In The Gas-Driven Inverse Liquid-Solid Fluidized Bed, Jiaqi Huang

Electronic Thesis and Dissertation Repository

A novel reactor named Gas-Driven Inverse Liquid-Solid Fluidized Bed (GDFB for short) was developed in this research. A vertical baffle divides the column into a riser and a downer. Inverse fluidization is driven by the gas and occurs in the downer, where hydrodynamics and their influencing factors were studied. In the solid-baffle system, four fluidization regimes were observed, including the packed bed, semi-fluidized bed, fully-fluidized bed, and circulating bed. Bed expansion ratio was higher for particles with a higher density and a smaller solids loading. Moreover, the average particle velocity was proportional to superficial gas velocity and higher for denser …


Crystal Engineering Of Active Pharmaceutical Ingredients With Low Aqueous Solubility And Bioavailability, Jenna M. Skieneh Aug 2017

Crystal Engineering Of Active Pharmaceutical Ingredients With Low Aqueous Solubility And Bioavailability, Jenna M. Skieneh

Electronic Thesis and Dissertation Repository

Approximately 75% of new molecular entities approved by the Food and Drug Administration (FDA) for use in the pharmaceutical industry are found to have poor aqueous solubility. This undesirable attribute leads to consequences such as higher doses required to reach therapeutic levels, greater vulnerability to food effects, lesser fraction absorbed in the small intestine and damage to the environment due to increased quantity of excretion. The addition of an excipient (i.e. a FDA approved inactive ingredient) to the molecular structure of an active pharmaceutical ingredient (API) through intermolecular bonding is of growing interest because the properties of the API can …


Bubble-Induced Inverse Gas-Liquid-Solid Fluidized Bed, Xiliang Sun Aug 2017

Bubble-Induced Inverse Gas-Liquid-Solid Fluidized Bed, Xiliang Sun

Electronic Thesis and Dissertation Repository

Gas-liquid-solid fluidized beds have been widely applied in wastewater treatment, however, the current method of wastewater process has several limitations. Hence, an improved method is in demand. A 3.5 height and 0.1534m inner diameter column was used to study the hydrodynamic characteristics of a bubble-induced three-phase inverse fluidized bed. Air, water and three types of low-density particles were employed as gas, liquid and solid phases.

The hydrodynamic properties in the bubble-induced three-phase fluidized bed were investigated to provide the basic information for the industrial process, such as flow regime, bed expansion ratio and phase holdups. A flow regime map containing …


Performance Characterization Of Coagulation Pretreatment For Two Industrial Effluents, Jing Wan Aug 2017

Performance Characterization Of Coagulation Pretreatment For Two Industrial Effluents, Jing Wan

Electronic Thesis and Dissertation Repository

In this work, performances of coagulation and flocculation were tested for two different industrial effluents. Coagulation-Flocculation and activated carbon adsorption were applied for the remediation of oil sands process-affected water (OSPW), generated from oil sands operations in Alberta, Canada. OSPW is a complex mixture of suspended solids, various suspended and dissolved organic compounds. Alum and natural coagulant Opuntia ficus-indica (OFI) were used as the coagulants, and the process was optimized to improve the removal of turbidity and dissolved organic carbon (DOC). The maximum removal of 98% and 63% in turbidity and DOC from OSPW, respectively occurred at pH=6.32, with an …


Enhanced Oxidation Of Organic Contaminants By Ferrate: Acid-Activated And Silica Gel-Enhanced Ferrate(Vi) Oxidation Processes, Kyriakos Manoli Aug 2017

Enhanced Oxidation Of Organic Contaminants By Ferrate: Acid-Activated And Silica Gel-Enhanced Ferrate(Vi) Oxidation Processes, Kyriakos Manoli

Electronic Thesis and Dissertation Repository

Recently, the tetraoxy high-valent iron(VI), known as ferrate(VI) (Fe(VI); FeVIO42), received a great attention as a water-treatment chemical, because of its unique oxidation, disinfection, and coagulation properties. Though Fe(VI) has shown remarkable efficiency in oxidizing several pollutants in water, it has sluggish reactivity with some emerging organic contaminants, especially at basic pH conditions. Thus, the main objective of this PhD thesis was to activate or catalyze Fe(VI) oxidation reactions, at mild alkaline pH conditions, to enhance the oxidative transformation of organic pollutants and reduce the required dosage of Fe(VI) and contact time.

The activation of …


Regeneration Potential Of Activated Petroleum Coke For Application In Oil Sands Process-Affected Water, Sreejon Das Aug 2017

Regeneration Potential Of Activated Petroleum Coke For Application In Oil Sands Process-Affected Water, Sreejon Das

Electronic Thesis and Dissertation Repository

Cost effective regeneration of spent adsorbent is crucial for large scale application of adsorption as a viable separation process. While adsorption studies are abundant in literature, systematic and comprehensive regeneration studies are seldom reported in open literature. A proprietary activated carbon from petroleum coke was used for the removal of model naphthenic acids (NAs) and organic compounds from oil sands process-affected water (OSPW). A systematic and comprehensive study was conducted to regenerate the adsorbents. Methanol with aqueous NaOH (pH adjusted to around 12) was applied to regenerate the spent commercially available granular activated carbon (GAC) and activated petroleum-coke (APC). Optimization …


Ultrasonic Techniques For Characterization Of Oil-Water Emulsion And Monitoring Of Interface In Separation Vessels, Embark Alshaafi Aug 2017

Ultrasonic Techniques For Characterization Of Oil-Water Emulsion And Monitoring Of Interface In Separation Vessels, Embark Alshaafi

Electronic Thesis and Dissertation Repository

Emulsions created at different stages of crude oil production and processing present a number of problems and challenges. There is need to monitor emulsion layer in separation vessel to avoid its ingress into separated oil or water phases. It is also important to study role of different impurities and conditions on emulsion stability which determines the ease or difficulty on its breakup to separate the individual phases. There is also need to have a good understanding of emulsion rheology and effect of different variables on its flow behavior. There is currently a lack of suitable technique to monitor emulsion layer …


Fabrication And Characterization Of Hybrid Nanocomposites By Matrix Assisted Pulsed Laser Evaporation, Songlin Yang Aug 2017

Fabrication And Characterization Of Hybrid Nanocomposites By Matrix Assisted Pulsed Laser Evaporation, Songlin Yang

Electronic Thesis and Dissertation Repository

Different methods have been applied to deposit hybrid nanocomposites which can be applied in various fields due to their light weight and multifunctional properties. Here, matrix assisted pulsed laser evaporation (MAPLE) equipment with 532 nm Nd:YAG laser is applied to fabricate three types of hybrid nanocomposites on different substrates.

Chemical synthesized FeCo nanoparticles were deposited on graphene sheets by MAPLE technique (laser fluence: 300 mJ/cm2). The effects of deposition time (t) on particle amount, shape and size have been investigated. Yttrium barium copper oxide (YBCO) materials are one type of high-temperature superconductive materials and …


Nanostructured Biosensor For Tear Glucose Detection Based On Bioluminescence Resonance Energy Transfer (Bret) Mechanism., Denghuang Zhan Aug 2017

Nanostructured Biosensor For Tear Glucose Detection Based On Bioluminescence Resonance Energy Transfer (Bret) Mechanism., Denghuang Zhan

Electronic Thesis and Dissertation Repository

Bioluminescence Resonance Energy Transfer (BRET), a sensitive, non-destructive and self-illuminated method, has been now commonly used to test protein interactions. Here, we describe a BRET sensor for non-invasively detecting glucose molecules. The sensor is made by the bioconjugation of quantum dots and recombinant protein. The recombinant protein contains the bacterial glucose binding protein (GBP) and a bioluminescent protein, Renilla luciferase (Rluc), used as the donor with the emission peak at 470 nm, which is able to excite the acceptor of BRET sensor made of cadmium tellurium quantum dots ( CdTe QDs) with the emission peak at 570 nm. The distance …


Genetic Engineering Studies Of Escherichia Coli And Microalgae For Expression Of Hydrolytic Enzymes And Development Of High Throughput Screening Technique, Shreyas S. Yedahalli Jul 2017

Genetic Engineering Studies Of Escherichia Coli And Microalgae For Expression Of Hydrolytic Enzymes And Development Of High Throughput Screening Technique, Shreyas S. Yedahalli

Electronic Thesis and Dissertation Repository

The field of biochemical engineering has made substantial progress through major advances in genetic and metabolic engineering with applications in various sectors such as energy, food science, pharmaceuticals, etc. The hosts used for this work are constantly broadening. A host particularly important for energy applications are microalgae. The potential to enhance microalgae genetically for energy applications is not well explored and was therefore investigated in this thesis. Non-photosynthetic micro-organisms and photosynthetic microalgae offer a potential approach to enhance sustainable biochemical production. In this study expression vectors for Escherichia coli (E. coli) and Chlorella vulgaris (C. vulgaris) …


Batch And Fed Batch Cultivation And Harvesting Of Nannochloropsis Gaditana For Environmental Applications, Roopa P. Devasya Jul 2017

Batch And Fed Batch Cultivation And Harvesting Of Nannochloropsis Gaditana For Environmental Applications, Roopa P. Devasya

Electronic Thesis and Dissertation Repository

Two challenging problems facing our world are the exhaustion of fossil fuels and climate change. Microalgae are eukaryotic phototrophs or prokaryotic cyanobacteria (blue green algae) that are able to capture CO2 and produce lipids suitable for biodiesel, thus can mitigate these challenges. The potential application of microalgae biomass for biofuel production is a clean and sustainable approach to replace fossil fuels. An important consideration for reducing the cost of biofuel is the economical production of algal biomass with high lipid yields. In this study, the marine microalgae Nannochloropsis gaditana were investigated for biomass and lipid production using two …


Investigation Of Lutein Production And Recovery From Chlorella Vulgaris Using Phototrophic Cultivation, Mengyue Gong Jul 2017

Investigation Of Lutein Production And Recovery From Chlorella Vulgaris Using Phototrophic Cultivation, Mengyue Gong

Electronic Thesis and Dissertation Repository

Microalgae have been recognized as a natural reservoir of the valuable commercial carotenoid lutein due to its high lutein content and fast growth cycle. However, the production of lutein from microalgal sources is not yet sufficiently cost-effective to compete with traditional marigold flower-based processing (Park et al., 2015). This thesis aims to investigate the factors affecting lutein production and recovery from microalgae using a phototrophic cultivation mode.

The closed photobioreactors can offer controlled conditions for faster microalgae growth. A coiled tubular tree photobioreactor (CTPBR) design was first investigated for cultivating the cold tolerant microalgae, Chlorella vulgaris UTEX 265, under various …


Design And Implementation Of Smart Sensors With Capabilities Of Process Fault Detection And Variable Prediction, An He Jun 2017

Design And Implementation Of Smart Sensors With Capabilities Of Process Fault Detection And Variable Prediction, An He

Electronic Thesis and Dissertation Repository

A typical sensor consists of a sensing element and a transmitter. The major functions of a transmitter are limited to data acquisition and communication. The recently developed transmitters with ‘smart’ functions have been focused on easy setup/maintenance of the transmitter itself such as self-calibration and self-configuration. Recognizing the growing computational capabilities of microcontroller units (MCUs) used in these transmitters and underutilized computational resources, this thesis investigates the feasibility of adding additional functionalities to a transmitter to make it ‘smart’ without modifying its foot-print, nor adding supplementary hardware. Hence, a smart sensor is defined as sensing elements combined with a smart …


Bioethanol Production Using Saccharomyces Cerevisae Cultivated In Sugarcorn Juice, Thirumalai Nambi Thiruvengadathan Jun 2017

Bioethanol Production Using Saccharomyces Cerevisae Cultivated In Sugarcorn Juice, Thirumalai Nambi Thiruvengadathan

Electronic Thesis and Dissertation Repository

For the first time, juice extracted from sugarcorn, a new Canadian energy crop, was used for bioethanol production. Physical and chemical characteristics of sugarcorn juice (SCJ) were determined. SCJ contained a maximum of 145 g/L of carbohydrates, with sucrose, glucose and fructose together contributing 80%. Effect of autoclaving and carbon filtration on juice sugars were investigated.

Shake flask fermentations using Saccharomyces cerevisiae grown in yeast extract supplemented SCJ produced a maximum of 45.6 g/L ethanol in 72 h. Bioreactor studies using un-supplemented SCJ achieved 40 g/L ethanol in 26 h, yielding a maximum of 0.46 g ethanol/g fermentable sugars, representing …


Magnetic Stimulation On The Growth Of The Microalga Nannochloropsis Oculata, Manuella Oliveira Jun 2017

Magnetic Stimulation On The Growth Of The Microalga Nannochloropsis Oculata, Manuella Oliveira

Electronic Thesis and Dissertation Repository

Fossil fuels, our principal sources of energy supply, are non-renewable and research is needed on alternatives that are renewable and potentially more environmentally friendly. Microalgae have been investigated as a future feedstock alternative to petroleum but the technology is still expensive and improvements are needed. Reduction in costs might be achieved by increasing algal biomass and lipid productivity. The lipids can be used to produce biofuels such as biodiesel and biojet fuel. The marine microalga Nannochloropsis oculata grows well and can accumulate high lipid content. In this study, the effects of static magnetic field stimulation (SMF) of 0 (control), 5, …


Preparation And Coating Of 5-Asa Pellets With A Novel Rotating Fluidized Bed, Shijia Guan May 2017

Preparation And Coating Of 5-Asa Pellets With A Novel Rotating Fluidized Bed, Shijia Guan

Electronic Thesis and Dissertation Repository

Although Mesalazine (5-ASA) demonstrates huge popularity in treating inflammatory bowel disease (IBD) due to its local effect on intestinal and colonic mucosa, it still demands more accurate and effective delivery of 5-ASA. As pellets embrace various technological and therapeutic advantages over the single-unit dosage form, this study aims at developing and optimizing the drug-loading and coating processes of 5-ASA pellets with a novel rotating fluidized bed. Powder layering and powder coating techniques, which are the same in essence, were applied in the drug-loading and coating processes, respectively. Three different coatings of 5-ASA pellets were achieved, resulting in extended, delayed and …


Use Of A Baffle To Enhance Distribution Of A Liquid Sprayed Into A Gas-Solid Fluidized Bed, Majid Jahanmiri Apr 2017

Use Of A Baffle To Enhance Distribution Of A Liquid Sprayed Into A Gas-Solid Fluidized Bed, Majid Jahanmiri

Electronic Thesis and Dissertation Repository

Bubbles in gas-solid fluidized beds are generally beneficial as they promote solids mixing, heat transfer and mass transfer. In most fluidized beds, the local bubble gas flux varies greatly over the cross-section. A novel triboelectric method is developed to measure the bubble gas distribution in a fluidized bed. A correlation relates the local bubble gas flux to the triboelectric signal generated by the impact of the gas bubbles on a triboprobe. Several signal analysis tools, such as power spectrum, cycle analysis and signal moments, were used to determine the best experimental fit for the profile of the bubble gas flux. …


Photoactive Properties Of Nanostructured Titania Modified Polyurethanes, Chao Chen Apr 2017

Photoactive Properties Of Nanostructured Titania Modified Polyurethanes, Chao Chen

Electronic Thesis and Dissertation Repository

In order to enhance both the photoactivity and physical/mechanical properties of titania/polyurethane (PU) nanocomposites, in-situ polymerization and film casting were investigated. Both self-degrading PU foams and self-cleaning PU coatings were prepared. Functional monomers were prepared usingDMPA (2,2-dimethylolpropionic acid) functionalized anatse TiO2 and P25 for integration into polyurethane foam with a "grafting-from" synthetic method. This technique was found to successfully reduce the agglomeration effect of titania nanoparticles inside the foams. In addition, the photodegradation rate was enhanced by > 120% over unmodified foam at an optimized loading of 3wt% DMPA functionalized anatase TiO2. The presence of DMPA functionalized P25 …


Study Of The Dynamics And Cost Analysis Of The Biogenerator, Tariq Abou Jarboua Apr 2017

Study Of The Dynamics And Cost Analysis Of The Biogenerator, Tariq Abou Jarboua

Electronic Thesis and Dissertation Repository

The BioGenerator is a promising energy storage solution that can be integrated with renewable power sources (i.e. wind and solar) to compensate the intermittent shortage of the renewable power sources and deliver a comprehensive power package. A trickling-bed bioreactor was considered to be used in the BioGenerator as an alternative to the initially studied ”air-lift” type bioreactor. Trickling-bed bioreactor is well known for its low power consumption for oxygen transfer. Dynamic study was conducted on lab scale trickling-bed bioreactor to investigate the effect of the ferrous iron feed interruption on the iron biooxidation rate. The study showed that the iron …