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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.
11

Production of a diesel fuel cetane enhancer from canola oil using supported metallic carbide and nitride catalysts

Sulimma, Hardi Lee 17 September 2008 (has links)
Six ã-Al2O3 supported metallic nitride and carbide catalysts were chosen for a scouting test for the production of a diesel fuel cetane enhancer from canola oil. The six catalysts chosen for study were ã-Al2O3 supported molybdenum (Mo) carbide and nitride, tungsten (W) carbide and nitride, and vanadium (V) nitride and carbide. All six catalysts were prepared by the impregnation method and characterized using various techniques. The six catalysts were screened for their affinity for oxygen removal, fatty acid conversion, alkane/olefin selectivity, hydrogen consumption, and gas-by product production from oleic acid. The scouting test was carried out at a reaction temperature of 390°C, a LHSV of 0.46 hr-1, and elevated hydrogen partial pressures of greater than 7000 kPa, in a laboratory microreactor in an upflow configuration. The scouting test revealed that the two molybdenum catalysts performed the best with oxygen removal near 100% and alkane/olefin content of greater than 30%. <p>Next, the supported molybdenum carbide and nitride catalysts were compared against one another over a wider range of operating conditions. A temperature range of 380 390°C, a LHSV range of 0.64 1.28 hr-1, and a hydrogen partial pressure of 7100 kPa were used. Both catalysts had the same metal loading of 7.4 wt% molybdenum. The two catalysts were compared on the basis of oxygen removal, alkane/olefin selectivity, diesel fuel selectivity, and hydrogen consumption, while using both triolein and canola oil as the feed. It was found that the supported molybdenum nitride was the superior choice for this process, specifically when using the more complex canola oil feed. The supported molybdenum nitride catalyst delivered oxygen removal of greater than 85%, alkane/olefin selectivity of greater than 20%, and diesel fuel selectivity of greater than 40%, for all conditions studied. <p>Finally, a preliminary catalyst and process optimization was carried out on the chosen ã-Al2O3 supported molybdenum nitride catalyst. The catalyst optimization consisted of varying the metal loading of the catalyst from 7.4 wt% to 22.7 wt%. The catalysts were examined over a temperature range of 390 410°C, a LHSV range of 0.9 1.2 hr-1, and a hydrogen partial pressure of 8300 kPa, with canola oil as the chosen feed. It was found that the increase in molybdenum loading on the catalyst delivered an average increase in the alkane/olefin selectivity of 43.2% and an average increase in the diesel fuel selectivity of 5.3 %. The process optimization studied a temperature range of 390 410°C, a LHSV range of 0.6 1.2 hr-1, and a hydrogen partial pressure range of 7800 - 8900 kPa, with canola oil as the chosen feed. Within the limits of the design, it was found that the optimum operating conditions were 395°C, 1.05 hr-1, and 8270 kPa. At these conditions the predicted yields of alkane/olefin products and diesel fuel are 47.3 and 50.5 g/100g liquid fed, respectively.
12

Stimulation of microsomal diacylglycerol acyltransferase activity from microspore-derived cell suspension cultures of oilseed rape

Byers, Susan D., University of Lethbridge. Faculty of Arts and Science January 1999 (has links)
Several factors including an unidentified endogenous substance were found to stimulate microsomal diacylglycerol acyltransferase (DGAT, EC 2.3.1.20) from a microspore-derived cell suspension culture of oilseed rape (Brassica napus L. cv Jet Neuf). Mg2+ salts were found to stimulate microsomal DGAT 14 to 23-fold. ATP and CoA were also found to stimulate the enzyme 2.4 and 12 fold respectively, although the effects were decreased in the presence of high Mg2+ concentrations. While microsomal DGAT activity was only slightly increased by the concentration of exogenous diacylglycerol in the reaction mixture it was increased substantially by the addition of exogenous phosphatidate. Other phospholipids tested were not found to have this stimulatory effect. During attempts to investigate possible covalent modification of the enzyme, the soluble fraction obtained from cell suspension homogenate was found to contain a small metastable organic molecule(s) which stimulated DGAT activity. Stimulation of microsomal DGAT by this factor was concentration dependent but not dependent on preincubation time. / xiii, 95 leaves : ill. ; 28 cm.
13

Molecular strategies for increasing seed oil content in canola

Wiehler, William B., University of Lethbridge. Faculty of Arts and Science January 2001 (has links)
Previous research has shown that microsomal DGAT activity from cultures of Brassica napus was stimulated by human acylation stimulating protein (ASP) and bovine serum albumin (BSA). Genetic constructs were engineered to facilitate the expression of ASP or BSA in developing seeds to test the stimulatory effect of these proteins at the site of TAG formation. As well, genetic constructs were designed to produce a truncation of the BSA polypeptide in an attempt to localize the portion fo the macromolecule responsible for stimulation of DGAT activity. An oleosin promoter was used for seed specific expression and to express the polypeptides at a precisely cooridnated time when oil was accumulating in the developing seeds. Lipid analysis coordinated time when oil was accumlating in the developing seeds. Lipid analysis was performed on the seeds of transgenic plants designed to cytosolically express these mammalian proteins and the seeds of control plants. The first generation data revealed that the total lipid within the mature seeds of ASP and BSA plants was not significantly different from the total lipid of negative control plants using both gravimetric and low resolution-nuclear magnetic resonance methods of analysis. The seeds from ASP 8 and ASP 10 plants, however, did produce significantly more lipid on a per seed basis as compared to negative control plants. The levels of the fatty acid composition for total acyl lipids were measured in these first generation transgenic plants. ASP 3 had significantly lower levels of linoleic acid, ASP 14 had significantly lower levels of a-linolenic acid and BSA 11 had significantly higher levels of both of these fatty acids in comparison to negative control plants. / xix, 245 leaves : ill. ; 28 cm.
14

A molecular genetic approach to reducing the saturated fatty acid content of canola oil

Bondaruk, Mandy, University of Lethbridge. Faculty of Arts and Science January 2003 (has links)
Brassica napus is known to contain an endogenous and soluble stearoyl-acyl carrier protein (^918:0-ACP) desaturase, but does not express a palmitic (16:0)-ACP desaturase. Levels of 16:0 are low in canola oil and are associated with enhanced cholesterol biosynthesis in humans. In an attempt to further reduce the saturated fatty acid (SFA) content of canola oil, B. Napus L. cv Westar was transformed with a cDNA encoding a ^916:0-ACP desaturase from cat's claw (Doxantha unguis-cati L.). Arabidopsis thaliana was also transformed with this cDNA. Transformation of both oilseeds resulted in increased production of palmitoleic acid (^16:1) and many other effects of fatty acid composition. Overall, the SFA content did not decrease in either oilseed and investigation to why this effect occurred was examined using transgenic B. napus. Molecular genetic testing on second generation B. napus also determined the plants contained the cDNA of interest and were transcribing the cDNA. / xxi, 155 leaves : ill. ; 29 cm.
15

MODELO DE GERENCIAMENTO DOS SERVIÇOS DE DISTRIBUIÇÃO FÍSICA NUMA AGROINDÚSTRIA

Rocha, Jiane Toller da 31 October 2006 (has links)
In a globalized and competitive world, logistics is receiving a lot of attention from business managers because of its importance concerning the fidelity of customers and their participation in the total costs of the company. Therefore, this paper aims to develop a model to the management of the services of physical distribution based on the six sigma strategy in an agroindustry that produces canola oil and it is located in the northwest of the state of Rio Grande do Sul, Brazil. The data were collected by using a questionnaire which refers to the level of satisfaction and the importance of the services offered by the company concerning the customers attendance; the kind of ordering, invoice service and payment; logistic of transports and the information given. In order to analyze the data it was used the descriptive statistics and the techniques of analyses Cluster hierarchic and Cluster k-means. The six customers who buy unmanufactured canola oil from this company took part on this study. The results showed that the customers are satisfied with most of the services offered by the company. It was also observed that the customers demonstrated a lot of satisfaction referring to the kind of ordering, invoice service and payment. However, the clients consider the attendance service as being the most important feature of the company. Based on these results, a model to the management of the services of physical distribution based on the six sigma strategy was proposed with the purpose of guaranteeing the quality of services offered. / Em um mercado globalizado e competitivo a logística começa a receber maior atenção por parte dos gestores empresariais, devido à sua importância quanto a fidelização de clientes e sua participação nos custos totais da empresa. Por isso, este trabalho tem por objetivo propor um modelo para o gerenciamento dos serviços de distribuição física, com base na estratégia seis sigma, em uma agroindústria produtora de óleo bruto de canola situada na região noroeste do Estado do Rio Grande do Sul. Os dados foram coletados por meio de um questionário, referentes ao grau de satisfação e importância dos serviços prestados pela empresa quanto ao atendimento; tomada de pedido, faturamento e pagamento; logística de transportes e informações prestadas. Para a análise dos dados utilizou-se a estatística descritiva e a técnica da análise de Cluster hierárquico e Cluster k-means. Fizeram parte deste estudo os seis clienteadquirem o óleo bruto de canola da empresa estudada. Os resultados mostraram que os clientes estão satisfeitos com a maioria dos serviços prestados pela empresa. Observou-se, também, que os clientes estão mais satisfeitos com os serviços referentes à tomada de pedidos, faturamento e pagamento. Porém, quanto ao grau de importância, eles consideram mais importante os serviços prestados no atendimento. Com base nestes resultados foi proposto um modelo de gerenciamento para os serviços de distribuição física baseado na estratégia seis sigma, visando garantir a qualidade dos serviços prestados.
16

Modulation of colon carcinogenesis by dietary ω-6/ω-3 fatty acid ratios : a chemopreventive strategy?

Abrahams, Celeste H. January 2015 (has links)
Philosophiae Doctor - PhD / The aim of this study was to determine whether dietary fats constituting specific ω-6/ω-3 fatty acids (FA) ratio has chemopreventive modulating effects on the development of colon cancer. Western diets intake of saturated FA (SATS) and ω-6 polyunsaturated FA (PUFA) are very high relative to low ω-3 PUFA consumption. This high ω-6 and low ω-3 FA intake, resulting in a high ω-6/ω-3 FA ratio, appears to have a promoting effect on disease outcome, whilst increased ω-3 FA intake exhibiting anti-cancer effects. An animal cancer model was employed to evaluate the effects of dietary fat ratios on chemically induced carcinogenesis during cancer promotion. This was to determine whether the FA diets have a promoting or inhibitory effect on early neoplastic lesions by quantifying aberrant crypt foci (ACF) development and monitoring the crypt cells proliferative and apoptotic indices. The expressions of genes associated with changes in cells redox balance were also assessed. Common dietary fats were combined to produce the dietary fat ratios: sunflower oil (S), borage oil (B) and fish oil (F). Combinations of these oils generated the different ω-6/ω-3 FA ratios: SB (ω-6/ω-3: 38:1), SF (ω-6/ω-3: 13:1) and SBF (10:1). To represent the Western diet's high ω-6/ω-3 FA ratio profile, S (ω-6/ω-3: 501: 1) was used as a control, and canola oil and olive oil as additional reference. The dietary fats had no toxic effects on the liver and kidney based on serum clinical biochemical measurements. Diets containing borage oil (SB and SBF diets), canola and olive oil decreased (p<0.05) the crypt multiplicity of large (≥7 crypts/focus) ACF, exhibiting anti-cancer effects by decreasing (p<0.05) the proliferative activity of the rat colon crypts. Borage oil's protective effect resulted from the enhanced supply of C18:3ω-6 that has anti-inflammatory and anti-proliferative properties. The observed decrease (p<0.05) in apoptosis in the ACF was also facilitated by the up- and down-regulation of DNA repair and DNA replication associated genes, Xpa and Ercc2 by borage oil, respectively. Canola oil and olive had the largest inhibitory effect on suppressing crypt multiplicity by reducing (p<0.05) proliferation in the colon. Both oils effected the up-regulation (p<0.05) of the expression of several oxidative stress and anti-oxidant defence genes mediating the regulation of cell proliferation. The increased supply of C18:1ω-9 (canola and olive) and total polyphenolic content (olive) protected cells against oxidative stress induced apoptosis, which provided interesting interactive effects between FA and polyphenolic oil constituents that should be further elucidated. In contrast, the fish oil containing (SF diet) and the control sunflower (S diet) increased (p<0.05) the total ACF and colon crypt multiplicity (≥7 crypts/focus) when compared to the SB, SBF, olive oil and canola oil diets. An increased resistance to oxidative stress induced apoptosis appears to facilitate fish oil’s enhancing effect on crypt multiplicity despite the increased supply of LC ω-3 FA, which are prone to oxidation and leads to increased oxidative stress. This protective effect on crypt multiplicity and ACF development was mainly due to enhanced cellular antioxidant and DNA repair responses through the up-regulation (p<0.05) of Gpx4 and Nudt1, which favoured the increase (p<0.05) of crypt cells proliferation.The in vitro study demonstrated that oil ratio emulsions (S: ω-6/ω-3 = 249:1; SB: ω-6/ω-3 = 28:1; SF: ω-6/ω-3 = 12:1 and SBF: ω-6/ω-3 = 12:1) had differential effects on the survival indices of HT-29 and Caco-2 colon cancer cells. Contrary to the in vivo model, fish oil (SF and SBF emulsions) significantly (p<0.05) reduced the viability and proliferation of both cell lines, with the HT-29 cells showing greater sensitivity to the oil’s anti-proliferative effect. The HT-29 cells exposure to increased levels of C20:5ω-3 and C22:6ω-3 predisposes it to lipid peroxidation that increases the potential for cell removal via apoptosis. However, apoptotic effects were absent due to the HT-29 cells removal via necrosis as the cells energy status (ATP production) was significantly (p<0.05) depleted. Similar to the animal cancer model, borage oil (SB and SBF emulsions) had a reducing (p<0.05) effect on cell proliferation in both cell lines. However, as ATP was decreased (p<0.05), the S, SF and SBF emulsions resulted in an increased (p<0.05) apoptotic response in the Caco-2 cells in a dose dependent manner. This response resulted from the altered FA and lipid composition effected by the oil emulsions. Increased (p<0.05) incorporation of C20:5ω-3 and C22:6ω-3 in membrane phospholipid, phosphatidylethanolamine (PE), resulted in a significant decrease (p<0.05) in total SATS and MUFA content. A decrease (p<0.05) in membranes ω-6/ω-3 FA ratio was noted as well. This effect seems to selectively favour the induction of apoptosis by borage oil (SB and SBF). Similarly, an increase (p<0.05) in the PC/PE ratio by all oil emulsions, and a decrease (S and SB) and increase (SF and SBF) (p<0.05) in the chol/PL ratio appears to facilitate apoptosis too. A different threshold of the FA and lipid composition parameters elicits the inhibition of cell proliferation utilising lower oil emulsion concentrations. Therefore, the dietary supply of fats characterised by a defined low ω-6/ω-3 FA ratio can selectively modulate the growth indices of colon cancer. Specific oil ratio combinations by incorporating borage oil and fish oil hereby provide a selective strategy for chemoprevention in the colon, although underlying interactions and threshold effects of specific FA seems to prevail that should be further unravelled. / Medical Research Council (MRC) and Cancer Association of South Africa (CANSA)
17

Affect of non-mixed condition of oxygen depletion and toxicity in a water body impacted by canola oil spill

Naik, Nita Mohan 14 July 2009 (has links)
No description available.
18

Thermal Characterization And Kinetics Of Diesel, Methanol Route Biodiesel, Canola Oil And Diesel-biodiesel Blends At Different Blending Rates By Tga And Dsc

Topa, Ece Hatice 01 September 2010 (has links) (PDF)
Application of thermogravimetric analysis to the renewable energy sources is a novel study and it has been becoming attractive by the researchers in recent years. In this thesis, thermal and kinetic properties of biodiesel as new energy source, diesel and canola oil have been analyzed by using very popular thermogravimetric analysis methods which are / Differential Scanning Calorimetry (DSC) and Thermogravimetry (TGA/DTG). The main aim of the study is to observe the combustion and pyrolysis behaviour of methanol route biodiesel and diesel blends at different blending rates. Additionally, combustion and pyrolysis behaviour of canola oil, the origin of biodiesel have been analysed to observe the transesterification reaction effect on biodiesel. Therefore, biodiesel, diesel, canola oil and blends of diesel and biodiesel at different percentages are exposed to isothermal heating under nitrogen and air atmosphere with a constant heating rate of 5, 10 and 15
19

Fornecimento de fontes lipídicas na dieta de poedeiras e seus efeitos sobre o desempenho, qualidade dos ovos, perfil de ácidos graxos e colesterol na gema

Faitarone, Ana Beatriz Garcia [UNESP] 17 August 2010 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:33:34Z (GMT). No. of bitstreams: 0 Previous issue date: 2010-08-17Bitstream added on 2014-06-13T19:04:39Z : No. of bitstreams: 1 faitarone_abg_dr_botfmvz.pdf: 754134 bytes, checksum: 45dd71e6381045c73eb898cfbd217a7f (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / Universidade Estadual Paulista (UNESP) / O presente experimento teve duração de 112 dias e teve por objetivo avaliar o desempenho e qualidade dos ovos de poedeiras leves alimentadas com dietas suplementadas com óleos vegetais. As aves foram distribuídas em um delineamento experimental inteiramente casualisado com 10 tratamentos - (T1 – Controle; T2 – inclusão de 2,5% de óleo de linhaça; T3 – inclusão de 2,5% de óleo de canola; T4 – inclusão de 2,5% de óleo de soja; T5 – inclusão de 5% de óleo de linhaça; T6 – inclusão de 5% de óleo de canola; T7- inclusão de 5% de óleo de soja; T8 – inclusão de 2,5% de óleo de linhaça + 2,5% de óleo de soja; T9 – inclusão de 2,5% de óleo de canola + 2,5% de óleo de soja e T10 – inclusão de 2,5% de óleo de linhaça + 2,5% de óleo de canola) - e seis repetições de oito aves por parcela experimental, perfazendo um total de 480 aves. Foram avaliadas o consumo de ração, a produção de ovos, o peso dos ovos, a massa de ovos, a conversão alimentar por dúzia e por quilograma de ovos produzidos, a gravidade específica dos ovos, a resistência da casca à quebra, a cor de gema, as percentagens de gema, albúmen e casca, a espessura de casca e o índice gema. Não foram observadas diferenças significativas entre os tratamentos para peso e massa de ovos, conversão alimentar por dúzia de ovos produzidos, gravidade específica dos ovos, resistência da casca à quebra, espessura de casca, percentagens de gema, albúmen e casca. Concluiuse que a suplementação de óleos vegetais, na ração de poedeiras comercias leves não promoveu melhoras no desempenho e na qualidade dos ovos / The present experiment lasted 112 days and aimed to weigh up the performance and eggs quality of light laying hens fed with diets supplemented with vegetal oil. The light laying hens were distributed on an completely randomized design with 10 treatments (T1 - control, T2- inclusion of 2.5% of linseed oil in the diet, T3- inclusion of 2.5% of canola oil in the diet; T4-inclusion of 2.5% of soybean oil in the diet; T5- inclusion of 5% of linseed oil in the diet; T6- inclusion of 5% of canola oil in the diet; T7-inclusion of 5% oil soy in the diet; T8- inclusion of 2.5% of linseed oil +2.5% soybean oil in the diet; T9- inclusion of 2.5% canola oil + 2.5% soybean oil in the diet and T10- inclusion of 2.5% of linseed oil + 2.5% of canola oil in the diet) and six repetition of eight birds by experimental sector, adding up to 480 birds. The ration consumption, the eggs production, the weight and mass, the alimentary conversion per dozen and per kilogram of produced eggs, specific gravity of the eggs, the strength egg shell to break, the yolk color, proportion of yolk, albumen and shell, shell thickness and yolk index were weighed up. Significant differences among the treatments for weight and eggs mass, food conversion by produced dozen eggs, specific eggs gravity, resistance to shell break, shell thickness, percentages of yolk, albumen and shell were not observed. It was concluded that the vegetal oils supplementation on the given diets to light laying commercial hens doesn’t affect the performance and the eggs quality
20

Experimental Investigation Of Use Of Canola Oil As A Diesel Fuel

Ozdemir, Ali 01 September 2008 (has links) (PDF)
In this study, canola oil has been selected for the test on a diesel engine and its suitability as an alternative fuel has been examined. To decrease the high viscosity of canola oil, the effect of temperature on viscosity has been researched. Then the fuel delivery system has been modified to heat canola oil before injecting the oil into the combustion chamber. Also, ethanol has been tested as an additive by blending with canola oil. An experimental setup has been installed according to standards to carry out tests. The set up has been controlled with a computer to take measurements more precisely and to perform experiment automatically. Experimental investigations have been conducted on a four cylinder, direct injection diesel engine. Full load-variable speed tests have been conducted to evaluate engine performance parameters. In addition 13 mode ESC test cycle has been performed to determine the exhaust emissions. Engine performance and emissions characteristics of canola oil and canola-ethanol blend containing 30% ethanol have been compared with those of baseline diesel fuel. Experimental results show that engine performance decreased for canola oil. Addition of ethanol into canola oil has been noticed to improve performance a little with respect to pure canola oil. Although, maximum performance has been obtained with diesel fuel, minimum specifics energy cost is obtained with canola oil. It has been observed that hydrocarbon (HC) emissions decrease with canola oil, blending ethanol with canola oil increase HC emissions and maximum values are read for diesel fuel. Carbon monoxide (CO) emissions have been observed to be the highest for canola oil but blending ethanol has a decreasing effect on CO emissions. As for particulate matter (PM), use of canola oil has been seen to be more pollutant than diesel but adding ethanol in canola reduces PM emissions significantly.

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