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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Assessment of hyperspectral features and damage modeling in bitumen flotation process

Bhushan, Vivek 06 1900 (has links)
Flotation process is mineral processing technique used for separating valuable minerals from the gangue. The research presented in this thesis deals with assessing features that can help in measuring the performance (observing) bitumen flotation process and modeling damage in flotation units. A timely measure of oilsands and process stream contents can be used to observe and control the separation performance. To this end, flotation experiments were conducted and hyperspectral images of the ore and the process stream were taken to determine whether spectral information can predict the bitumen and fines content of ore samples and establish relationship a between these variables and the froth colour. Several features that appear to correspond to clay and quartz were present. Flotation cells are prone to wear damage by particles entrained in the slurry. A wear damage model was developed to predict the damage accumulated over a period of time. Particle image velocimetry experiments were conducted on physical flotation model to understand the flow behavior of the solid particles near the wall of the flotation unit. A preliminary wear test was conducted for qualitative assessment of wear. Recommendations were made for validating the damage model. / Engineering Management
2

Assessment of hyperspectral features and damage modeling in bitumen flotation process

Bhushan, Vivek Unknown Date
No description available.
3

NITROGEN CYCLING, OPTIMIZATION OF PLANT NUTRITION AND REMOTE SENSING OF LEAF NUTRIENTS IN WILD BLUEBERRIES (VACCINIUM ANGUSTIFOLIUM AIT.)

Maqbool, Rizwan 10 December 2013 (has links)
This thesis consists of three sections that provide detailed knowledge of nutrient estimation and management in wild blueberry production. The first section investigated the main and interactive effects of long term fertilizer (NPK) enrichments on soil mineral nitrogen, organic nitrogen and carbon, microbial biomass nitrogen and carbon, net mineralization and net nitrification in wild blueberry soils. The second section studied the optimization of wild blueberry growth, development, foliar nutrients and harvestable yields by using response surface methodology. The third section examined nutrient estimation technologies using field spectroscopy. The remote sensing data was analysed with a combination partial least squares regression and variable selection algorithms (Chemometric analysis). The results indicated elevated nitrification activity under nitrogen enrichments, mainly performed by heterotrophs, report unusually high levels of dissolved organic carbon (> 150 C ha-1), a fungal dominated soil system and high concentration of soluble organic nitrogen in the crop year of production. Nitrification and high dissolved organic carbon levels were observed in connection with possible nitrogen saturation and potential environmental hazards. The results imply a need for nitrification inhibition measures. Results from field studies examining the main and interactive effects of soil applied N, P and K suggested that applications of nitrogen (35 kg ha-1), phosphorus (40 kg ha-1) and potassium (30 kg ha-1) were required to optimize growth, development and harvestable yields of wild blueberry. Under these fertilizer rates, the corresponding predicted harvestable yield was 4,126 kg ha-1 that is as much as 13% higher than would be produced by commonly used fertilizer rate in the industry. This study presented new leaf nutrient ranges for sprout and crop years for wild blueberry fields in Atlantic Canada. Hyperspectral remote sensing technologies were used for estimating macro and micro nutrients. This study provides critical information on wavelengths important for nutrient estimation in reflectance spectra (400-2500 nm). The results and inferences from this thesis may be employed to improve crop production, increase economic returns and health of soil and sustainability of wild blueberry production in Nova Scotia. / This study was undertaken to examine the response of the wild blueberry plant to soil applied fertilizers and encompasses soil nitrogen and carbon pools, plant growth and development, leaf nutrient concentrations and harvestable yields. In addition, given the vast area in which wild blueberry fields are located, the study also examined the feasibility of assessing plant nutrient status through the use of remote sensing hyperspectral technologies. Our results emphasize the importance of monitoring for soil nitrogen and carbon pools in the context of accelerated nitrogen cycling, nitrogen saturation, the fine-tuning of current leaf nutrient ranges in Atlantic Canada in connection to fertilizer rates, the possibility of estimating leaf nutrient contents by remote sensing technologies all with the aim of optimizing wild blueberry yields. In terms of statistical techniques, this thesis used response surface methodologies with a central composite design as a means of discovering, the main and interactive effects of soil applied fertilizers to determine the most appropriate soil nitrogen levels and leaf nutrient ranges that correlate to the highest harvestable yields. The remote sensing data used to estimate leaf nutrients concentrations, various models that combined chemometrics and response surface methodologies for determining model efficiencies with aim of getting informative wavelengths in wild blueberry fields.
4

Raman Spectroscopy and Hyperspectral Analysis of Living Cells Exposed to Nanoparticles

Ahlinder, Linnea January 2015 (has links)
Nanoparticles, i.e. particles with at least one dimension smaller than 100 nm, are present in large quantities in ambient air and can also be found in an increasing amount of consumer products. It is known that many nanomaterials have physicochemical properties that differ from physicochemical properties of the same material in bulk size. It is therefore important to characterize nanoparticles and to evaluate their toxicity. To understand mechanisms behind nanotoxicity, it is important to study the uptake of nanoparticles, and how they are accumulated. For these purposes model studies of cellular uptake are useful. In this thesis metal oxide and carbon-based nanoparticles have been studied in living cells using Raman spectroscopy. Raman spectroscopy is a method that facilitates a non-destructive analysis without using any fluorescent labels, or any other specific sample preparation. It is possible to collect Raman images, i.e. images where each pixel corresponds to a Raman spectrum, and to use the spectral information to detect nanoparticles, and to identify organelles in cells. In this thesis the question whether or not nanoparticles can enter the cell nucleus of lung epithelial cells has been addressed using hyperspectral analysis. It is shown that titanium dioxide nanoparticles and iron oxide nanoparticles are taken up by cells, and also in the cell nucleus. In contrast, graphene oxide nanoparticles are mainly found attached on the outside of the cell membrane and very few nanoparticles are found in the cell, and none have been detected in the nucleus. It is concluded that graphene oxide nanoparticles are not cytotoxic. However, a comparison of Raman spectra of biomolecules in cells exposed to graphene oxide, unexposed cells and apoptotic cells, shows that the graphene oxide nanoparticles do affect lipid and protein structures. In this thesis, several multivariate data analysis methods have been used to analyze Raman spectra and Raman images. In addition, super-resolution algorithms, which originally have been developed to improve the resolution in photographic images, were optimized and applied to Raman images of cells exposed to submicron polystyrene particles in living cells.
5

Micro-Raman Imaging and Hyperspectral Analysis of Tibiotarsi from Chick Embryos Exposed to Sublethal Doses of Platinum Group Metals

Stahler, Adam Christopher 24 September 2012 (has links)
No description available.
6

Automated Spectral Identification of Materials using Spectral Identity Mapping

Cannon, Robert William 23 August 2013 (has links)
No description available.

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