Engineering Commons^™

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-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 …

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

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

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) …

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 …

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

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, …

Disinfection By-Products Formation After Coagulation Of Algal Extracellular And Intracellular Organic Matters, Tianyiru Chen

Electronic Thesis and Dissertation Repository

Algal organic matter (AOM) is found in high concentration during algal bloom season in drinking water systems, which is generally categorized into extracellular organic matter (EOM) and intracellular organic matter (IOM). These compounds are not well removed in traditional water treatment methods such as coagulation, and are the precursors of subsequent disinfection by-products (DBPs) during chlorination of water. In this study, EOM and IOM content of four different algae were quantified measuring dissolved organic carbon (DOC), UV absorbance at 254 nm and turbidity. Coagulation using alum (Al₂(SO₄)₃•16H₂O)was used to remove the algal …