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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.
51

ETHANOL DEHYDRATION IN A PRESSURE SWING ADSORPTION PROCESS USING CANOLA MEAL

2013 March 1900 (has links)
Canola meal was used as an adsorbent in a pressure swing adsorption (PSA) apparatus for ethanol dehydration. The experiments were conducted at different pressures, temperatures, vapor superficial velocities, vapor concentrations and particle sizes. Adsorption experiments were performed at equilibrium and breakthrough points. The results demonstrated that canola meal can break the azeotropic point 95.6 wt% and produce over 99 wt% ethanol. At elevated temperature, feed water concentration, and vapor superficial velocity, it was found that the mass transfer rate increased. In addition, the mass transfer rate decreases when either the total pressure or the size of the adsorbent particles are increased. Breakthrough curves were simulated and the overall mass transfer resistance was evaluated at all experimental runs. The internal mass transfer resistance was identified as the relevant mass transfer mechanism. For canola meal, the equilibrium water/ethanol uptake was achieved at 100, 105, and 110˚C. The Frenkel-Halsey-Hill (FHH) and Guggenheim-Andrson-de-Boer (GAB) models perfectly simulated the water adsorption isotherms. By applying Dubinin-Polanyi model to the experimental data, canola meal was identified as a large pore (non-porous) material. The heat of adsorption on canola meal with particle size of 0.43-1.18 mm was determined to be -32.11 kJ/mol. The result confirms that the adsorption process is an exothermic phenomenon and is of physical type due to the fact that the value obtained as the heat of adsorption is negative and its magnitude is within the range 20–80 kJ/mol. The equilibrium water uptake on canola meal was similar to that reported for other starchy and cellulosic adsorbents, while the ethanol uptake was higher. Water saturated canola meal was successfully regenerated by passing nitrogen at 110˚C which is lower than that for molecular sieves commonly used in industry for bioethanol dehydration. The canola meal bio-adsorbent was re-used for more than 32 cycles and no significant change in adsorption capacity was observed.
52

Effect of replacing fish meal with simple or complex mixtures of vegetable ingredients in diets fed to Nile tilapia (<i>Oreochromis niloticus</i>)

Borgeson, Tracy L 01 March 2005
The effect of fractionating flax, peas and canola on the digestibility of these ingredients in <i>Nile tilapia</i> was determined. Dehulling of flax, and processing peas and canola to pea protein concentrate and canola protein concentrate, resulted in significant increases in the energy and dry matter digestibilities of these products (P < 0.05). Protein digestibility was significantly improved by dehulling flax but there were no differences in the protein digestibilities of pea, canola and their protein concentrates. The ability of the most digestible ingredients from Experiment 1 to replace fish meal in tilapia diets was examined in a 9 week growth trial. The diet formulations were arranged in a 2 x 4 factorial design with 2 types of plant protein mixtures used to replace fish meal (simple: soyabean meal and maize gluten meal or complex: soyabean meal, maize gluten meal, dehulled flax, pea protein concentrate and canola protein concentrate) and 4 levels of protein originating from fish meal (100%, 67%, 33% and 0%). Diets were formulated to contain equal digestible protein (380 g kg-1) and digestible energy (17.63 MJ kg-1). Fifty six tanks containing 10 male <i>Nile tilapia</i> were used in this experiment. Fish were fed to apparent satiation twice daily for a total of 63 days and growth and feed intake was measured for the entire experimental period. On day 64 of the experiment, one fish per tank was euthanized and a 1 cm segment of small intestine was prepared for measurement of villus length. The average daily gains, specific growth rates and feed efficiencies of fish fed diets with 0% fish meal were significantly lower than fish fed diets with the 33, 67 or 100% fish meal levels. Fish fed the complex diets had significantly higher average daily gains, specific growth rates, feed:gain ratios and protein efficiency ratios than those fed the simple diets. Villus length decreased with decreasing levels of fish meal and increased with increased diet complexity but the effects were not significant. The results indicated that replacement of fish meal with a complex mixture of plant ingredients may allow a greater replacement of fish meal in diets fed to <i> Nile tilapia</i>.
53

The effect of feeding a barley/canola meal pellet to feedlot steers on performance, rumen fermentation, and eating behaviour

Williams, Logan Mae 13 September 2007
Two trials were conducted to evaluate effects of feeding barley/canola meal pellets on feedlot performance, subacute ruminal acidosis (SARA), and feeding behaviour in feedlot steers. In trial 1, 350 beef steers (285 ± 22 kg) were backgrounded and finished on pelleted barley and canola meal (PB) or rolled barley and canola meal (RB) diets. Backgrounding DMI was lower (P < 0.05) for PB steers but ADG did not differ (P > 0.05) and feed efficiency (FE) tended (P < 0.1) to be improved. During finishing and the total trial DMI and ADG were lower (P < 0.05) but FE was improved (P < 0.05) for the PB treatment. Steers fed PB were on feed longer (P < 0.05). Steers fed PB showed more variation in DMI (P < 0.05) than steers fed RB. Carcass composition and quality were similar between the treatments.<p>Trial 2 utilized 4 ruminally fistulated beef steers in a 4 x 4 latin square, 2 x 2 factorial trial. Factors were processing (pelleted vs. rolled) and grain type (barley vs. corn). All treatments included canola meal. Each 23 d period consisted of a 19 d adaptation period followed by a 24 h rumen fluid collection period, and a 24 h eating behaviour study. There were no grain type x processing interactions (P > 0.05) or effect of grain type (P > 0.05) on any of the variables. Eating behaviour did not differ (P < 0.05) between treatments. Processing had no effect (P > 0.05) on rumen ammonia or volatile fatty acid (VFA) concentration, proportion of acetate or butyrate, or rumen osmolality. Steers fed pelleted grain had lower (P < 0.05) rumen pH measurements, a greater (P < 0.05) molar proportion of propionate, and decreased (P < 0.05) acetate:propionate ratio. To reflect the feedlot trial corn was removed from the model. Rumen VFA concentration was higher (P < 0.05) and pH lower (P < 0.05) for the PB steers. Results show performance during backgrounding was improved but finishing performance depressed in PB steers. Further research is necessary to reduce the risk of SARA when feeding PB during finishing.
54

Improvement of canola protein gelation properties through enzymatic modification

Pinterits, Alexandra 12 September 2006 (has links)
The objective of this study was to improve canola protein gelation properties with the use of enzymes. Both cross-linking and limited proteolysis were explored. Enzyme treatments were performed prior to heat induced gelation. A texture analyzer, sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) and scanning electron microscopy were used to characterize the resulting networks. Enzymatic cross-linking with transglutaminase was shown to improve the gelation of canola protein isolate (CPI). To the contrary, proteolysis with trypsin, ficin and bromelin, did not enhance the gelation properties of CPI. / October 2006
55

Belowground Contributions of Pea and Canola to Soil Nitrogen Pools and Processes

2013 June 1900 (has links)
Nitrogen (N) contained in roots and rhizodeposits represents a significant input of crop residue-N into soil that is often unaccounted, despite its contribution to the total N budget and its influence on soil nutrient cycling. Utilizing 15N-labeling methodologies under controlled conditions, the goal of this research was to quantify the input of belowground N (BGN), including rhizodeposits and roots, to soil and to investigate the influence of BGN on soil N cycling processes from the major pulse and oilseed crop grown across the Canadian prairies—namely, field pea and canola, respectively. Using continuous 15N2 labeling, the input of fixed-N to rhizosphere soil from pea plants amounted to less than 2% of the total plant N assimilated via fixation. Nodulation and root 15N enrichment were positively related to rhizosphere 15N enrichment, suggesting that the relatively low input of fixed-N to soil was due to low N fixation in this system. Shoot 15N-labeling techniques enabled a higher 15N enrichment in roots; as a result, rhizodeposition was detected in the rhizosphere as well as the surrounding bulk soil. Rhizodeposition accounted for 7.6 and 67% of plant N and BGN, respectively, in mature pea. Temporal changes in the pattern of rhizodeposition were detected as evidenced by differing 15N enrichment in rhizosphere versus bulk soils. In comparison to pea, a higher proportion of BGN contributed to the total residue-derived N from canola. The higher quantity of N rhizodeposition by canola was related to greater root biomass. However, pea rhizodeposition contributed more to soil inorganic N pools; this was sustained over time, as a higher proportion of pea BGN contributed to the growth of a subsequent wheat crop. In addition, wheat uptake of residue-derived N was twice as much from belowground compared to straw residues. Whereas the abundance of denitrifying bacterial communities in the rhizosphere was uncoupled from rhizodeposition and denitrification enzyme activity (DEA), root-derived 15N correlated with DEA in pea and canola. This research highlights the importance of belowground inputs from differing crop species on N budgets and soil N cycling.
56

Effect of replacing fish meal with simple or complex mixtures of vegetable ingredients in diets fed to Nile tilapia (<i>Oreochromis niloticus</i>)

Borgeson, Tracy L 01 March 2005 (has links)
The effect of fractionating flax, peas and canola on the digestibility of these ingredients in <i>Nile tilapia</i> was determined. Dehulling of flax, and processing peas and canola to pea protein concentrate and canola protein concentrate, resulted in significant increases in the energy and dry matter digestibilities of these products (P < 0.05). Protein digestibility was significantly improved by dehulling flax but there were no differences in the protein digestibilities of pea, canola and their protein concentrates. The ability of the most digestible ingredients from Experiment 1 to replace fish meal in tilapia diets was examined in a 9 week growth trial. The diet formulations were arranged in a 2 x 4 factorial design with 2 types of plant protein mixtures used to replace fish meal (simple: soyabean meal and maize gluten meal or complex: soyabean meal, maize gluten meal, dehulled flax, pea protein concentrate and canola protein concentrate) and 4 levels of protein originating from fish meal (100%, 67%, 33% and 0%). Diets were formulated to contain equal digestible protein (380 g kg-1) and digestible energy (17.63 MJ kg-1). Fifty six tanks containing 10 male <i>Nile tilapia</i> were used in this experiment. Fish were fed to apparent satiation twice daily for a total of 63 days and growth and feed intake was measured for the entire experimental period. On day 64 of the experiment, one fish per tank was euthanized and a 1 cm segment of small intestine was prepared for measurement of villus length. The average daily gains, specific growth rates and feed efficiencies of fish fed diets with 0% fish meal were significantly lower than fish fed diets with the 33, 67 or 100% fish meal levels. Fish fed the complex diets had significantly higher average daily gains, specific growth rates, feed:gain ratios and protein efficiency ratios than those fed the simple diets. Villus length decreased with decreasing levels of fish meal and increased with increased diet complexity but the effects were not significant. The results indicated that replacement of fish meal with a complex mixture of plant ingredients may allow a greater replacement of fish meal in diets fed to <i> Nile tilapia</i>.
57

The effect of feeding a barley/canola meal pellet to feedlot steers on performance, rumen fermentation, and eating behaviour

Williams, Logan Mae 13 September 2007 (has links)
Two trials were conducted to evaluate effects of feeding barley/canola meal pellets on feedlot performance, subacute ruminal acidosis (SARA), and feeding behaviour in feedlot steers. In trial 1, 350 beef steers (285 ± 22 kg) were backgrounded and finished on pelleted barley and canola meal (PB) or rolled barley and canola meal (RB) diets. Backgrounding DMI was lower (P < 0.05) for PB steers but ADG did not differ (P > 0.05) and feed efficiency (FE) tended (P < 0.1) to be improved. During finishing and the total trial DMI and ADG were lower (P < 0.05) but FE was improved (P < 0.05) for the PB treatment. Steers fed PB were on feed longer (P < 0.05). Steers fed PB showed more variation in DMI (P < 0.05) than steers fed RB. Carcass composition and quality were similar between the treatments.<p>Trial 2 utilized 4 ruminally fistulated beef steers in a 4 x 4 latin square, 2 x 2 factorial trial. Factors were processing (pelleted vs. rolled) and grain type (barley vs. corn). All treatments included canola meal. Each 23 d period consisted of a 19 d adaptation period followed by a 24 h rumen fluid collection period, and a 24 h eating behaviour study. There were no grain type x processing interactions (P > 0.05) or effect of grain type (P > 0.05) on any of the variables. Eating behaviour did not differ (P < 0.05) between treatments. Processing had no effect (P > 0.05) on rumen ammonia or volatile fatty acid (VFA) concentration, proportion of acetate or butyrate, or rumen osmolality. Steers fed pelleted grain had lower (P < 0.05) rumen pH measurements, a greater (P < 0.05) molar proportion of propionate, and decreased (P < 0.05) acetate:propionate ratio. To reflect the feedlot trial corn was removed from the model. Rumen VFA concentration was higher (P < 0.05) and pH lower (P < 0.05) for the PB steers. Results show performance during backgrounding was improved but finishing performance depressed in PB steers. Further research is necessary to reduce the risk of SARA when feeding PB during finishing.
58

An Experimental Investigation of Microexplosion in Emulsified Vegetable-Methanol Blend

Nam, Hyungseok 2012 May 1900 (has links)
Vegetable oil is one of the most widely available renewable sources of energy that can be used to meet the world’s demands. Many vegetable oils also have the advantage of containing little to no detectable amounts of nitrogen. Recently, research studies have revealed that when two liquids with different vapor pressure values are formed into droplet-like emulsions, a micro-explosion effect can happen under specific environmental conditions. Understanding the micro-explosion phenomena can help increase the efficiency of bio-emulsion combustion as well as reduce pollution levels. Many researchers have conducted experiments to find the optimal condition that induces microexplosion effects. Microexplosion is also associated with the formation of shock waves characteristic of explosions at larger scales. However, little is known about how emulsion composition and droplet size affect the micro-explosion process. Through this research, methanol-in-vegetable oil emulsion has been studied from the microexplosion point of view using custom made electric furnace equipment with a high speed camera system and an acoustic sensor system. The main goal of this study is to understand the effect of emulsion compositions, chamber temperatures, and droplet sizes on the characteristics of microexplosion. First, an n-hexadecane-in-water emulsion was prepared to validate the performance of the custom-made experimental apparatus using previous published data. Methanol-in-canola oil emulsions with different compositions were also prepared and used to compare the micro-explosion phenomena with water as a volatile compound. Microexplosion events of the blended fuels were captured using a high speed camera and an acoustic sensor. The wave signals generated by the microexplosion were analyzed after converting the signals using a Fast Fourier Transform coded in Matlab. One of the major findings of this research work was that higher temperatures and higher concentrations of high vapor pressure fluids such as methanol and water in emulsions causes a high probability of microexplosion event due to the sudden expansion of the emulsified fluid. Also, the effect of size on microexplosion was evident in the greater probability of explosion. Methanol-in-canola oil emulsion with 15 % methanol with droplets size of 200 m placed in a furnace chamber heated to 980 ˚C showed optimal microexplosion behavior based on the formation of fine droplets. Also, smaller droplets produced higher frequencies, which could be used to detect microexplosion without high speed imaging. When large droplets microexploded, lower frequencies were detected in all the blends.
59

Anatomic and transcriptomic characterization of the canola (Brassica napus) funiculus during seed development.

Chan, Ainsley January 2013 (has links)
Canola (Brassica napus) is a $19.3 billion industry for the Canadian economy annually, largely because of the demand for the oil derived from the seeds of this crop plant. Seed development and accumulation of important nutrients requires coordinated interactions between all seed regions, including the funiculus. The funiculus is a structure of the seed that serves as the only connection between the filial seed and the parent plant, yet its development and underlying transcriptional programs have not been explored. Using light and transmission electron microscopy, I completed an anatomical study of the funiculus over the course of development, from the mature ovule to the post-mature green seed stage. My results show that all three plant tissue systems of the funiculus undergo profound changes at the histological and ultrastructural level. To understand the programs that orchestrate these changes in the globular stage funiculus, I used laser microdissection coupled with RNA-sequencing. This produced a high-resolution dataset of the mRNAs present in each of the three tissue systems of the funiculus. Various clustering analyses and gene ontology term enrichment analysis identified several important biological processes associated with each tissue system. My data show that cell wall growth occurs in the epidermis, photosynthesis occurs in the cortex, and tissue proliferation and differentiation occurs in the vasculature. The importance of these processes in supporting overall seed growth and development is discussed, which can have profound implications in the genetic modification of the canola seed through manipulating the transcriptional activity of the funiculus.
60

Blackleg of Canola: Survey of virulence and race structure of the Leptosphaeria maculans pathogen population in Canada and evaluation of the genetic variation in the L. maculans global population

Liban, Sakaria 14 September 2015 (has links)
Phoma stem canker (aka Blackleg) caused by the fungal pathogen Leptosphaeria maculans is a major disease affecting Canola (Brassica napus L.). This study examined 674 L. maculans isolates collected in 2010 and 2011 from western Canada at ten avirulence gene loci. Overall, certain alleles were more prevalent with AvrLm6 and AvrLm7 present in >85% of isolates and AvrLm3, AvrLm9, and AvrLepR2 present in <10% of isolates. This study also examined the genetic diversity of Leptosphaeria maculans populations around the world. Blackleg disease is found in most countries where Brassica spp. are cultivated and there are indications that L. maculans is an expanding species displacing the less aggressive Leptosphaeria biglobosa. Twenty two microsatellite primers were used to screen 96 isolates from 8 countries. A phylogenetic tree to assess the evolutionary relationship between regions was generated and the results indicated that genetic diversity was correlated with geographic location. / October 2015

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