Liu Y.,Low Carbon Technology |
Lu H.,Low Carbon Technology |
Ampong-Nyarko K.,Alberta Agriculture and Rural Development |
MacDonald T.,Olds College |
And 3 more authors.
Catalysis Today | Year: 2015
Biodiesel was produced by transesterification in the presence of trace sulfuric acid (0.02-0.1. wt% of oil mass). The kinetics for the transesterification of corn oil with ethanol was investigated between 155-195. °C. The transesterification in the pseudo-homogeneous system consisted of three consecutive steps. All steps were found to be second order reactions, with the first and the second steps being irreversible, while the third step was reversible. It was observed that the apparent rate constants of the forward reactions increased linearly with increasing acid concentration. Compared to the initial two steps of the ethanolysis reaction, the effect of the reversible transformation in the third step is significant, as the conversion of monoglyceride to glycerol is difficult. In addition, the presence of free fatty acids (<30. wt%), water (<3. wt%), and the use of stirring had little effect on the final content of biodiesel. Finally, it was observed that methanol exhibited a higher reactivity than ethanol in transesterification, while corn oil exhibited higher reactivity than Pennycress oil. © 2015 Elsevier B.V.
Sutton R.K.,UN Lincoln |
Harrington J.A.,UW Madison 25 Agricultural Hall |
Skabelund L.,Kansas State University |
MacDonagh P.,Kestrel Design Group |
And 2 more authors.
Journal of Green Building | Year: 2012
Native prairie species have been both promoted and questioned in their ability to serve as vegetative covers for green roofs. The green roof environment with its exposure to intense sun and wind and limited moisture restricts the capacity for a large diversity of species. The result has been, in many cases, a standard, low-diversity mix of Sedum species often focused on ornament and minimizes the potential for wider environmental benefits. We reviewed the ecological literature on prairie and grassland communities with specific reference to habitat templates from stressed environmental conditions and examined analogs of prairie-based vegetation on twenty-one existing green roofs. We found that many, but not all prairie and grassland species will survive and thrive on green roofs, especially when irrigated as needed or given adequate growing medium depth. We raise several important questions about media, irrigation, temperature, biodiversity and their interactions needing more study.
Harker K.N.,Agriculture and Agri Food Canada |
O'Donovan J.T.,Agriculture and Agri Food Canada |
Blackshaw R.E.,Agriculture and Agri Food Canada |
Hall L.M.,University of Alberta |
And 10 more authors.
Canadian Journal of Plant Science | Year: 2013
A field study was conducted at eight sites in western Canada to determine the influence of agronomic inputs on fatty acid profiles and biodiesel quality of canola. Protein and chlorophyll concentration and fatty acid profiles were determined from seed samples at all sites. Oil was extracted from canola seed samples from three sites, converted to biodiesel, and subjected to standard protocols. Protein concentration increased at higher than recommended rates of nitrogen (N) and the higher canola seeding rate (150 seeds m-2) reduced chlorophyll levels in canola oil. All biodiesel samples fell below new oxidation stability tolerance levels (minimum 8 h). However, given the routine addition of commercial antioxidant additives, all biodiesel samples from this study were suitable for blending in middle distillate fuels. Cloud point values were lowest at normal N (1×) rates. Normal N rates increased stearic acid content, whereas high N rates (1.5×) increased gadoleic acid content. Low seeding rates (75 seeds m-2) increased palmitic acid content. The combination of normal N (1×) with a high seed rate (150 seeds m-2) increased oleic acid content. Conversely, the combination of high N (1.5×) with a low seed rate (75 seeds m-2) increased linolenic acid content. Gadoleic acid content increased in the continuous canola rotation versus the canola-wheat-canola rotation; similar trends were observed with palmitic, linoleic, and linolenic acid. Oleic acid tended to be higher in canola rotated with wheat. Cold filter plugging point (CFPP) was predicted based on saturated fatty acid content. Usually, a high seeding rate (150 seeds m-2) combined with a normal N rate (1×) led to the most favourable (lowest) CFPP values. Low CFPP values were also associated with canola rotated with wheat compared with continuous canola production. Seeding rate, N, and crop rotation influenced protein and chlorophyll concentration, fatty acid profiles, cloud point, and CFPP.
Hamlin R.,University of Otago |
Knight J.,University of Otago |
Cuthbert R.,Olds College
Renewable Agriculture and Food Systems | Year: 2015
In many developed countries agriculture is undergoing significant changes. Traditional commodity markets are increasingly being supplemented or even displaced by niche markets served by firms producing specialty products. The purpose of this paper is to determine why firms seek out niche markets and what contributes to their success. This paper investigates the characteristics that make niche markets attractive to small and medium-sized agricultural firms and the ways in which these firms become highly adapted for their chosen niche. Results indicate that forming alliances and the development of horizontal and vertical networks are among the most common and most important strategies employed by successful niche marketers. The study found that firms market niche products as part of a portfolio of products that often includes an anchoring commodity. Results also suggest that aggressive growth and pricing strategies may negatively impact a firm's ability to sustain barriers to entry. The development of a niche positioning strategy is often the outcome of a reaction to an existing situation rather than of a priori strategic planning. Copyright © Cambridge University Press 2015
Meadus W.J.,Agriculture and Agri Food Canada |
Duff P.,Agriculture and Agri Food Canada |
McDonald T.,Olds College |
Caine W.R.,Caine Research Consulting
Journal of Animal Science and Biotechnology | Year: 2014
Camelina sativa is an oil seed crop which can be grown on marginal lands. Camelina seed oil is rich in omega-3 fatty acids (>35%) and γ-tocopherol but is also high in erucic acid and glucosinolates. Camelina meal, is the by-product after the oil has been extracted. Camelina meal was fed to 28 d old weaned pigs at 3.7% and 7.4% until age 56 d. The camelina meal supplements in the soy based diets, improved feed efficiency but also significantly increased the liver weights. Gene expression analyses of the livers, using intra-species microarrays, identified increased expression of phase 1 and phase 2 drug metabolism enzymes. The porcine versions of the enzymes were confirmed by real time PCR. Cytochrome 8b1 (CYP8B1), aldehyde dehydrogenase 2 (Aldh2), and thiosulfate transferase (TST) were all significantly stimulated. Collectively, these genes implicate the camelina glucosinolate metabolite, methyl-sulfinyldecyl isothiocyanate, as the main xeniobiotic, causing increased hepatic metabolism and increased liver weight. © 2014 Meadus et al.; licensee BioMed Central Ltd.