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Serson, William Richard. "INCREASING RENEWABLE OIL CONTENT AND UTILITY." UKnowledge, 2017. http://uknowledge.uky.edu/pss_etds/89.
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Since the dawn of agriculture man has been genetically modifying crop plants to increase yield, quality and utility. In addition to selective breeding and hybridization we can utilize mutant populations and biotechnology to have greater control over crop plant modification than ever before. Increasing the production of plant oils such as soybean oil as a renewable resource for food and fuel is valuable. Successful breeding for higher oil levels in soybean, however, usually results in reduced protein, a second valuable seed component. We show that by manipulating a highly active acyl-CoA: diacylglycerol acyltransferase (DGAT) the hydrocarbon flux to oil in oilseeds can be increased without reducing the protein component. Compared to other plant DGATs, a DGAT from Vernonia galamensis (VgDGAT1A) produces much higher oil synthesis and accumulation activity in yeast, insect cells and soybean. Soybean lines expressing VgDGAT1A show a 4% increase in oil content without reductions in seed protein contents or yield per unit land area. Furthermore, we have screened a soybean fast neutrino population derived from M92-220 variety and found three high oil mutants that do not have reduced levels of protein. From the F2 plant populations we quantitatively pooled the high oil and low oil plants and performed comparative genomics hybridization (CGH). From the data it appears that two families have a 0.3 kb aberration in chromosome 14. We are performing further analysis to study this aberration and develop markers for molecular breeding. Mutagenic techniques are also useful for developing other traits such as early flowering varieties and adapting new high oil crops to a new region. Chia (Salvia hispanica) is an ancient crop that has experienced an agricultural resurgence in recent decades due to the high omega 3 fatty acid (ω-3) content of the seeds and good production potential. The area of cultivation has been expanded to Kentucky using mutagenized populations and the composition traits are similar to that of the original regions of cultivation in Central and South America.
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Wiehler, William B., and University of Lethbridge Faculty of Arts and Science. "Molecular strategies for increasing seed oil content in canola." Thesis, Lethbridge, Alta. : University of Lethbridge, Faculty of Arts and Science, 2001, 2001. http://hdl.handle.net/10133/126.
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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.
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Wiehler, William B. "Molecular strategies for increasing seed oil content in canola." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2001. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp04/mq61049.pdf.
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Plimpton, Shari L. "Factors affecting the oil content of potato chips and the application of near infra-red reflectance to on-line moisture and oil content measurements /." The Ohio State University, 1985. http://rave.ohiolink.edu/etdc/view?acc_num=osu1487263399026461.
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Kilaru, Aruna. "Understanding the Regulation of Oil Biosynthesis in Oil-Rich Tissues for the Purpose of Enriching Plant Oil Content to Generate Biofuels." Digital Commons @ East Tennessee State University, 2013. https://dc.etsu.edu/etsu-works/4776.
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Triacylglycerols (TAGs) are stored in variable amounts (1-90 % by dry weight) in seed and non-seed tissues of various plant species. To gain insights into tissue- and species-specific regulation and biosynthesis of TAG in plants, we used 454 pyro and Illumina sequencing and generated transcriptome for eight species (brassica, castor, nasturtium, euonymus, oil palm, date palm, and avocado). In all tissues analyzed, an increased expression was noted for genes mostly associated with fatty acid biosynthesis in plastid, but much less increase in those for TAG assembly in the endoplasmic reticulum. Furthermore, hexose metabolism in plastid, relative to cytosol, appeared to be crucial in most oil-rich tissues, which is likely associated with directing high pyruvate flux toward plastid fatty acid synthesis. We also identified that WRINKLED1 transcription factor acts as a master switch in regulating oil biosynthesis in most oil-rich seed and non-seed tissues of monocot and dicot plants, suggesting a highly conserved mechanism. Overall, our studies point to distinctive modes of regulation of fatty acid biosynthesis and TAG assembly that are conserved in both seed and non-seed oil-rich plants, which can be extended to other crops for the purpose of generating biofuels.
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RAPOSO, GELMIREZ MARTINS. "NUMERICAL SIMULATION FOR HYDROCYCLONE DESIGNED TO HIGH OIL CONTENT APPLICATION." PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2008. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=13794@1.
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A separação ciclônica vem se tornando nas últimas décadas um processo
cada vez mais utilizado na separação gás-líquido, líquido-líquido e sólidolíquido,
principalmente na indústria do petróleo. Com o crescente aumento das
prospecções marítimas torna-se necessário reduzir o peso e a dimensão de
equipamentos. Isto pode ser conseguido com a separação ciclônica, uma vez que
pode-se criar um campo centrífugo diversas vezes superior ao campo
gravitacional, tornando possível o desenvolvimento de equipamentos bastante
compactos. A principal diferença entre os diversos ciclones é a sua geometria. A
otimização dos mesmos para as variadas aplicações é, a cada ano, baseada menos
em experimentos e mais em modelos matemáticos. No presente trabalho foi
investigada a adequação dos modelos de turbulência de Tensões de Reynolds
RSM (Reynolds Stress Model) e Grandes Escalas LES (Large Eddy Simulation)
para a previsão do escoamento em um hidrociclone de alto teor de óleos através
da comparação com dados experimentais e numéricos disponíveis na literatura.
Após essa etapa foi investigada a influência de diversos parâmetros operacionais
e geométricos como vazão, rugosidade e comprimento do hidrociclone no
escoamento. Ambas as metodologias mostraram vantagens e deficiências, sendo
que o modelo LES apresentou precisão superior com relação aos parâmetros
turbulentos. Com relação à variação nos parâmetros do equipamento, a
metodologia RSM foi capaz de prever corretamente, de acordo com evidências
experimentais, a mesma tendência de redução de perda de carga com redução da
vazão, aumento da rugosidade e comprimento.Cyclonic separation has became more and more important during the last decades as a unit process for gas-liquid, liquid-liquid and solid-liquid separation, mostly in the Petroleum industry. The off-shore exploration’s growth requires the development of smaller and lighter equipment. This can be achieved by cyclonic separation once centrifugal fields are several times stronger than gravity. This allows the construction of very compact systems. The major difference between the various cyclones is their geometry. Cyclone optimization for different uses is, every year, less based on experiments and more based on mathematical models. In the present work, the applicability of turbulent models, Reynolds Stress Model (RSM) and Large Eddy Simulation, was investigated to predict the flow inside a high oil content hydrocyclone, comparing the results with experimental and numerical data available in the literature. After this point, the influence on flow of operational and geometric parameters such as inlet flow, roughness and hydrocyclone length was evaluated. Both models have shown advantages and problems, being LES more accurate over turbulent parameters. Regarding the changing on hydrocyclone parameters, RSM model was able to foresee, on good agreement with experimental data, the expected results like reduction on pressure drop with: the inlet flow decreasing; increasing of roughness; and length.
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Ayoola, Olakunle Thomas. "Nigerian Oil and Gas Industry Content Development Act's Perceived Performance Impact." ScholarWorks, 2017. https://scholarworks.waldenu.edu/dissertations/3383.
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Petroleum-producing companies in Nigeria were forced to increase spending on Nigerian-sourced materials and services from $8 billion to $13 billion since 2010, due to the Nigerian Oil and Gas Industry Content Development Act. The act was enacted in 2010 to support local firms and improve the companies' performance. However, there is sparse research on how the act affected the companies' performance. This study was an examination of the impact of the act on the companies' performance. Bandura's social cognitive theory was the theoretical framework. The research questions of this descriptive correlational study were used to examine the act's effect on employee and organizational performance. The independent variable was employees' perception of the level of implementation of the act. The dependent variables were employees' perceived task and perceived organizational business performance. Collection of interval level survey data from 372 full-time employees of the 5 major petroleum-producing companies in Nigeria was possible by anchoring only the ends of the Likert scale with words. The Pearson product-moment correlation results indicated that the independent variable correlated positively with each dependent variable. The exploratory factor analysis results indicated that the act had a positive effect on the employees' internal competence factor and the organizations' operational performance factor. The results are significant for Nigerian government officials and managers of the companies in understanding the impact of the act on performance. The outcomes have potential implications for positive social change through improved implementation strategies to achieve the objectives of the act. Researchers could focus on examining the impact of the act on employees' internal competence factor in future studies.
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Hizbai, Biniam T. "Comparative Mapping of QTLs Affecting Oil Content, Oil Composition, and other Agronomically Important Traits in Oat (Avena sativa L.)." Thèse, Université d'Ottawa / University of Ottawa, 2012. http://hdl.handle.net/10393/23481.
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Groat oil content and composition are important quality traits in oats (Avena sativa L). These traits are controlled by many genes with additive effects. The chromosomal regions containing these genes, known as quantitative trait loci (QTL), can be discovered through their close association with markers. This study investigated total oil content and fatty acid components in an oat breeding population derived from a cross between high oil ('Dal') and low oil ('Exeter') parents. A genetic map consisting of 475 DArT (Diversity Array Technology) markers spanning 1271.8 cM across 40 linkage groups was constructed. QTL analysis for groat oil content and composition was conducted using grain samples grown at Aberdeen, ID in 1997. QTL analysis for multiple agronomic traits was also conducted using data collected from hill plots and field plots in Ottawa, ON in 2010. QTLs for oil content, palmitic acid (16:0), stearic acid (18:0), oleic acid (18:1), linoleic acid (18:2) and linolenic acid (18:3) were identified. Two of the QTLs associated with oil content were also associated with all of the fatty acids examined in this study, and most oil-related QTL showed similar patterns of effect on the fatty acid profile. These results suggest the presence of pleiotropic effects on oil-related traits through influences at specific nodes of the oil synthesis pathway. In addition, 12 QTL-associated markers (likely representing nine unique regions) were associated with plant height, heading date, lodging, and protein content. The results of this study will provide information for molecular breeding as well as insight into the genetic mechanisms controlling oil biosynthesis in oat.
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Anderson, Chris. "Genetic analysis of oil content and composition in oat, Avena sativa L." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2001. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp05/MQ62684.pdf.
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Van, der Merwe Hester E. (Hester Elizabeth). "Factors affecting rind oil content of lemon (Citrus limon (L.) Burm. f.)." Thesis, Stellenbosch : Stellenbosch University, 2005. http://hdl.handle.net/10019.1/50352.
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Thesis (MScAgric)--University of Stellenbosch, 2005.ENGLISH ABSTRACT: Essential oils are derived from volatile natural oils in plants and have been used by mankind for millennia. Citrus essential oils are widely used in various applications and lemon [Citrus limon (L.) Burm. f.] rind oil is the most important citrus oil in commerce. Rind oil glands are located in the exocarp, or flavedo, of the fruit and are formed schizogenously. The purpose of this study was to quantify the factors affecting rind oil content of lemons. The factors studied were light exposure and canopy position, growing region in South Africa, genotype, i.e. scion and rootstock, as well as the relationship between seedless clones of cultivars and the cultivars from which the seedless clones were derived, and various plant growth regulators were screened to determine whether they influenced rind oil content. Following the sampling of fruit from different positions in the tree's canopy, light exposure was found to affect rind oil content of 'Eureka' lemon fruit. Fruit borne on the outside of trees, higher in the tree, north-facing or not within the hedgerow had the highest rind oil content. Photosynthetically active radiation data supports the hypothesis that rind oil content is correlated with light exposure. To optimise rind oil content of lemons, trees should not be too dense or too high as to overshadow the lower parts of adjacent trees. South Africa has a diverse climate, and rind oil content from fruit produced in different growing regions was compared. 'Eureka' lemon fruit from Upington had the highest rind oil content in all seasons sampled. Fruit from Malelane and Marble Hall ranked second to Upington and rind oil content for fruit from Karino was intermediate. Rind oil content for fruit from Vaalharts was the lowest at each sampling time. When rind oil content was regressed against cumulative heat units there was a positive linear relationship in 2003, but in 2004 the relationship was weak. However, III general, rind oil content increased with increasing heat unit accumulation. A large variation exists among citrus cultivars and rootstocks and their effect on fruit growth and quality. 'Lirnoneira 8A', followed by 'Cicily', 'Lisbon' and 'Genoa' had the highest rind oil content. 'Villafranca', 'Messina' and 'Yen Ben Lisbon' had the lowest rind oil content. Rind oil content from 'Eureka' lemon fruit was disappointingly low. Seedless cultivars, 'Eureka SL' and 'Lisbon SL', had ~18.0% higher rind oil content than the seeded cultivars from which they were derived. With regards to rootstock, fruit from lemon trees budded on non-invigorating rootstocks, e.g. X639 [e. reshni Hort. ex Tan. x P. trifoliata (L.) Raf.], had the highest rind oil content, whereas rind oil content was low on invigorating rootstocks such as rough lemon (e. jambhiri Lush.). Synthetic gibberellins, cytokinins, ethylene and auxins were applied on lemon trees at different times and concentrations to screen their ability to enhance rind oil content. Of all the gibberellins and cytokinins applied, Promalin®, a combination of gibberellic acid 4/7 and benzyl adenine-phosphate, a cytokinin, had a small, but nonsignificant effect on rind oil content. Ethephon, which induces ethylene synthesis, affected rind oil content in 2004, when applied 8 weeks before harvest. However, ethephon and aminoethoxyvinylglycine (AVG, an ethylene biosynthesis inhibitor) had an inconsistent effect on lemon rind oil content. Auxins did not affect rind oil content. Further experiments should be conducted, especially on the timing and concentration of applied gibberellins, e.g. Promalin®, and ethephon.
AFRIKAANSE OPSOMMING: Essensiële olies is vlugtige, natuurlike plantolies wat al vir eeue deur die mens gebruik word. Sitrus essensiële olies het verskeie toepassings en van hierdie sitrus olies is dié verkry uit suurlemoenskil [Citrus limon (L.) Burm. f.] die belangrikste. Skiloliekliere is in die eksokarp, of flavedo, van die vrug geleë en vorm skisogenies. Die doelwit van hierdie navorsing was om faktore wat die olie-inhoud van suurlemoenskil affekteer te kwantifiseer. Faktore wat bestudeer is sluit ligblootstelling en posisie in die boom, produksiearea in Suid-Afrika, en genotipe (bo- en onderstam) in. Ook is saadlose klone vergelyk met die kultivars waaruit dit ontwikkel is. Verskeie plantgroeireguleerders se effek op skilolie-inhoud is ook geëvalueer. Ligblootstelling het skilolie-inhoud van 'Eureka' suurlemoene affekteer toe monsters van verskillende posisies in die boomtop vergelyk is. Vrugte aan die noorde- en buitekant, of hoër in die boom het die hoogste skilolie-inhoud gehad. Vrugte binne die plantry het minder skilolie bevat. Fotosinteties-aktiewe ligvlakmetings ondersteun die hipotese dat skilolieinhoud korreleer met ligblootstelling. Vir opitmale skilolie-inhoud in suurlemoene is dit dus belangrik dat bome nie te dig of te hoog moet wees nie, sodat dit nie die onderste dele van aangrensende bome oorskadu nie. Sitrus word in diverse klimaatstreke in Suid-Afrika verbou. Gevolglik is die skilolie-inhoud van vrugte uit verskillende produksieareas vergelyk. 'Eureka' suurlemoenvrugte uit Upington het met elke monsterneming die hoogste skilolie-inhoud gehad, gevolg deur vrugte uit Malelane en Marble Hall. Skilolie-inhoud van vrugte uit Karino was gemiddeld, terwyl vrugte van Vaalhaarts met elke monsterneming die laagste skilolie-inhoud gehad het. Regressie van skilolie-inhoud op kumulatiewe hitte-eenhede het 'n positiewe lineêre verwantskap in 2003 getoon. Hoewel die verwantskap swakker was in 2004, neem skilolieinhoud oor die algemeen toe met toenemende akkumulasie van hitte-eenhede. Sitruskultivars en -onderstamme varieer aansienlik in groeikrag en vrugkwaliteit. 'Lirnoneira 8A', gevolg deur 'Cicily', 'Lisbon' en 'Genoa' het die hoogste skilolie-inhoud gehad, terwyl 'Villafranca', 'Messina' en 'Yen Ben Lisbon' die laagste skilolie-inhoud gehad het. Die skilolie-inhoud van 'Eureka' suurlemoene was teleurstellend laag. Die skilolie-inhoud van die saadlose kultivars, 'Eureka SL' en 'Lisbon SL', was -18% hoër as die skilolie-inhoud van die kultivars waaruit dit ontwikkel is. Vrugte van bome wat op minder groeikragtige onderstamme geënt is, bv. X639 [C reshni Hort. ex Tan. x P. trifoliata (L.) Raf.], het 'n hoë skilolie-inhoud gehad, terwyl vrugte van bome op groeikragtige onderstamme, bv. growweskilsuurlemoen (C jambhiri Lush.), minder skilolie bevat het. Sintetiese gibberelliene, sitokiniene, etileen en ouksiene is op verskillende tye en teen verskillende dosisse op suurlemoenbome toegedien om die effek daarvan op skilolie-inhoud te bepaal. Promalin® (G~+7 en bensieladenienfosfaat) het 'n klein effek op skilolie-inhoud gehad, maar die effek was nie statisties beduidend nie. Ethephon, wat etileensintese induseer, het skilolie-inhoud in 2004 geaffekteer toe dit 8 weke voor oes toegedien is. Ethephon en aminoetoksievinielglisien (AVG, 'n etileenbiosintese inhibeerder) het egter nie 'n konstante effek op suurlemoen skilolie-inhoud gehad nie. Ouksiene het nie skilolie-inhoud geaffekteer me. Verdere eksperimente is veral nodig op die toedieningstyd en konsentrasie van toegediende gibberelliene, bv. Promalin®, en ethephon.
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Garcia-Rodriguez, Francisco. "Asphaltene content effect on the combustion of Mexican heavy fuel oil droplets." Thesis, University of Salford, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.244869.
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Koski, A. (Anna). "Applicability of crude tall oil for wood protection." Doctoral thesis, University of Oulu, 2008. http://urn.fi/urn:isbn:9789514287237.
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Moisture content control is a very effective way of protecting timber. Treatments with environment-friendly, biodegradable tall oil are known to reduce the capillary water uptake of pine sapwood greatly, but despite the good results achieved there have been two problems that limit the use of tall oil for wood protection, the large amount of oil needed and the tendency for the oil to exude from the wood. This work was undertaken in order to obtain an understanding of the mechanism of wood protection by means of crude tall oil (CTO) and to find technical solutions to the main problems limiting its use for industrial wood protection.
It is shown that the emulsion technique is one way of solving the first problem, as it provides high water-repellent efficiency at considerably lower oil retention levels. The fact that water is used as a thinner in this technique instead of the commonly used organic solvents is beneficial from environmental, economic and safety points of view.
It is also shown that although the drying properties of CTO are inadequate for use as such in wood preservation, its oxidation and polymerization can be accelerated considerably by means of iron catalysts, which prevent the oil from exuding out of the wood. This also increases the water repellent efficiency of CTO treatment.
Most impregnation oils do not dry when applied in large quantities, because they hinder the diffusion of air through the wood, which supplies the necessary oxygen. Limiting of the oil uptake by the means of the emulsion technique disturbs the airflow to a lesser extent, and thus enhances the drying process. Hence, both the emulsion technique and the use of an iron catalyst improve both the water-repellent efficiency of tall oil treatment and the rate of drying of the oil, thus solving the two main problems related to wood impregnation with tall oil in one single-stage treatment which can be used in existing wood preservation plants. This is advantageous from both an industrial and an economic point of view.
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Silva, Muñoz Lydia. "Ontology-based metadata for e-learning content." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2004. http://hdl.handle.net/10183/6207.
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Atualmente a popularidade da Web incentiva o desenvolvimento de sistemas hipermídia dedicados ao ensino a distância. Não obstante a maior parte destes sistemas usa os mesmos recursos do ensino tradicional, apresentado o conteúdo como páginas HTML estáticas, não fazendo uso das novas tecnologias que a Web oferece. Um desafío atual é desenvolver sistemas educativos que adaptem seu conteúdo ao estilo de aprendizagem, contexto e nível de conhecimento de cada aluno. Outro assunto de pesquisa é a capacidade de interoperar na Web reutilizando objetos de ensino. Este trabalho apresenta um enfoque que trata esses dois assuntos com as tecnologias da Web Semântica. O trabalho aqui apresentado modela o conhecimento do conteúdo educativo e do perfil do aluno pelo uso de ontologias cujo vocabulário é um refinamento de vocabulários padrões existentes na Web como pontos de referência para apoiar a interoperabilidade semântica. As ontologias permitem a representação numa linguagem formal dos metadados relativos a objetos de ensino simples e das regras que definem suas possíveis formas de agrupamento para desenvolver objetos mais complexos. Estes objetos mais complexos podem ser projetados para se adequar ao perfil de cada aluno por agentes inteligentes que usam a ontologia como origem de suas crenças. A reutilização de objetos de ensino entre diferentes aplicações é viabilizada pela construção de um perfil de aplicação do padrão IEEE LOM-Learning Object Metadata.Nowadays, the popularity of the Web encourages the development of Hypermedia Systems dedicated to e-learning. Nevertheless, most of the available Web teaching systems apply the traditional paper-based learning resources presented as HTML pages making no use of the new capabilities provided by the Web. There is a challenge to develop educative systems that adapt the educative content to the style of learning, context and background of each student. Another research issue is the capacity to interoperate on the Web reusing learning objects. This work presents an approach to address these two issues by using the technologies of the Semantic Web. The approach presented here models the knowledge of the educative content and the learner’s profile with ontologies whose vocabularies are a refinement of those defined on standards situated on the Web as reference points to provide semantics. Ontologies enable the representation of metadata concerning simple learning objects and the rules that define the way that they can feasibly be assembled to configure more complex ones. These complex learning objects could be created dynamically according to the learners’ profile by intelligent agents that use the ontologies as the source of their beliefs. Interoperability issues were addressed by using an application profile of the IEEE LOM- Learning Object Metadata standard.
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Aflatuni, Abbas. "The yield and essential oil content of mint (Mentha ssp.) in northern Ostrobothnia /." Oulu : Oulun Yliopisto, 2005. http://herkules.oulu.fi/isbn9514277465/.
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朱翠珊 and Tsui-shan Chu. "Factors affecting the structure and oil content of steamed-and-fried instant noodles." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2000. http://hub.hku.hk/bib/B31222511.
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Bin, Rostani Khairul. "Effect of crude oil vanadyl porphyrin content and blending on heat exchanger fouling." Thesis, Imperial College London, 2013. http://hdl.handle.net/10044/1/24933.
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Fouling in the pre-heat train of crude oil distillation unit is a normal occurrence in oil refineries. With the increasing trend of heavy crude oil processing, blending of oils becomes a norm practice in a refinery. Fouling could be enhanced if incompatible oils were blended together. Also, heavy oils typically contain high trace metals composition and their effect towards fouling is yet to be explored. This study has been looking into the effect of changes in the original composition and inter-molecular stability of crude oils towards fouling. A batch system was designed and developed to produce a deposit sample from 3 crude oils of industrial interest. The reactor was successfully commissioned and an operating procedure was established. In the first part of the work, various concentrations of Vanadium were added to crude oils and subjected to high temperature in the test section. The resultant deposits and liquid products were analysed for their molecular structure and weight distribution. Analysis by Inductively Coupled Plasma Mass Spectrometer (ICP-MS) shows the added Vanadium are largely concentrated in the deposits. The amount of deposits produced increases with the concentration of Vanadium in the original samples. Analyses by Size Exclusion Chromatogram (SEC), Gas Chromatography (GC) and UV-Fluorescence Spectroscopy (UVF) show larger and more complex molecules in deposits from oils with high concentration of Vanadium. In the second part, the compatibility regions of crude oil blends were established prior to analysis in the reactor. More deposits were produced from incompatible oil blends though these were lighter and less complex than that of compatible blends. Also, oils that were blended from the incompatible region produced deposits of bigger molecular weight distributions and more complex structures. Results of Thermo-Gravimetric Analysis (TGA) confirmed those of SEC's and UVF's of which more volatile components were recorded in active blended deposit samples.
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Chu, Tsui-shan. "Factors affecting the structure and oil content of steamed-and-fried instant noodles /." Hong Kong : University of Hong Kong, 2000. http://sunzi.lib.hku.hk/hkuto/record.jsp?B22053955.
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Alaswad, Alaa A. "DEVELOPMENT OF CHEMICALLY MUTAGENIZED SOYBEAN POPULATIONS FOR IMPROVING SOYBEAN SEED OIL CONTENT AND FORWARD AND REVERSE GENETICS SCREENING." OpenSIUC, 2014. https://opensiuc.lib.siu.edu/theses/1421.
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Soybeans are among seeds the common plant foods that contains high protein contents and high oil. The protein provides about 35 to 38 percent of the seeds calories compared to around 20 to 30 percent in other legumes and many animal products. The quality of soy protein is notable and approaches the quality of meat and milk. Unlike many other good sources of protein, soybeans are low in saturated fat and are cholesterol-free. Its proteins provide all the important amino acids, most the amounts needed by humans (NSRL, 2010). As the most consumed vegetable oil in the world, soybean oil has been used substantially in the food industry (Soystats, 2010). Its utilization is determined by its fatty acid composition, with commodity soybean oil typically 13% palmatic acid (16:0), 4% stearic acid (18:0), 20% oleic acid (18:1), 55% linoleic acid (18:2), and 8% linolenic acid (18:3). The change of fatty acid profiles to improve soybean oil quality has been a long time goal of many researchers throughout the world. Biodiesel is an up and coming trend in energy production. Breeding effort can be undertaken in order to produce a higher energy profile soybean oil. Using ethyl-methanesulfonate (EMS) mutagenesis effects on DNA, significant changes to the genes and gene network underlying the protein and oil profile can be achieved. These changes are hard to accomplish using standard breeding techniques. In addition, high amount of linolenic and stearic acid are very important for fuel and biodiesel production, but are not good for food production due to the fact that such oil is oxidized easily and the food goes rancid quickly. However, soybean oil with elevated amount of oleic acid is desirable for food, because this monounsaturated fatty acid improves the nutrition and oxidative stability of soybean oil compared to other oils. In order to improve the quality of soybean oil and processed foods, chemically mutagenized soybeans have been developed in this project. Seeds harvested from individual M3 and M4 plants (from 2 successive years 2012 and 2013) were analyzed for protein content, oil composition, and content. Moreover, seven phenotypic traits including oil analysis (stearic, palmitic, oleic, linolenic and linoleic), seed protein content, weight of the seeds (High yield), seeds color, stem length, germination rates, and branch architecture were collected and analyzed in this project of soybean `Forrest' mutagenized population. The result of this research showed that there were 25 significantly different lines (p< 0.05) compare to the wild type, which is useful for developing mutants with altered oil and fatty acid compositions in soybean.
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Kim, Namhoon. "Epoxidation and di-hydroxylation of camelina sativa oil." Thesis, Kansas State University, 2014. http://hdl.handle.net/2097/18252.
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Master of ScienceDepartment of Grain Science and Industry
Xiuzhi Susan Sun
Plant oil-based raw materials have become more attractive alternatives in polymer industry as fossil resources depletion and environmental concerns continue to arise. Camelina (camelina sativa L.) seed contains about 45% of oil and about 90% of the oil is unsaturated fatty acids such as linoleic acid, α-linolenic acid, and erucic acids. It also provides the advantages of low cost and low fertilizer demand. Functionalized oils such as epoxidized camelina oil (ECO) and di-hydroxyl camelina oil (DCO) can be used for resins, adhesives, coatings, etc. The objectives of this work were to synthesize and characterize ECO and DCO from camelina oil. The epoxidation reaction of camelina oil was completed with formic acid and hydrogen peroxide. Catalyst ratio, reaction time, and temperature effects on the epoxidation reaction were studied. The optimum epoxy content of 7.52 wt% with a conversion rate of 76.34% was obtained from camelina oil using excess hydrogen peroxide and a molar ratio of formic acid of less than 1 for 5 hours in 50 °C. Camelina oil yields higher epoxy content (7.52 wt%) than soybean oil (6.53 wt%); however, soybean oil had a higher conversion rate of 80.16% compared to camelina oil because of uniform fatty acids distribution. In this study, we found that epoxidation efficiency is significantly affected by fatty acids composition, structure, and distribution. DCO was synthesized from ECO with different reaction parameters. The ring opening of ECO was performed with water, perchloric acid, and THF as proton donor, catalyst, and solvent respectively. Hydroxyl value of DCO was measured, and the maximal hydroxyl value was 369.24 mg KOH/g. physical properties of DCO were characterized by acid value and moisture content; thermal properties of DCO were obtained using different scanning calorimeter (DSC), thermalgravimetric analysis (TGA). Amount of solvent and acid catalyst addition affected the hydroxyl value and residual acid in DCO. Heat capacity, phase transition temperatures, and thermal stability of DCO were obtained and showed higher values than ECO’s. The DCO showed higher peel adhesion when it was formulated with epoxidized soybean oils through UV curing because camelina oil allows higher epoxy content, which results in higher hydroxyl values.
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Bondaruk, Mandy, and University of Lethbridge Faculty of Arts and Science. "A molecular genetic approach to reducing the saturated fatty acid content of canola oil." Thesis, Lethbridge, Alta. : University of Lethbridge, Faculty of Arts and Science, 2003, 2003. http://hdl.handle.net/10133/145.
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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.
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Holmes-Miller, Leah. "The Effect of Supplementing Grazing Dairy Cattle Diets with Fish Oil and Linseed Oil on Milk CLA and Omega-3 Fatty Acid Content." Available to subscribers only, 2009. http://proquest.umi.com/pqdweb?did=1885462201&sid=2&Fmt=2&clientId=1509&RQT=309&VName=PQD.
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Brown, William. "Effects of supplementing grazing dairy cows with fish oil and linseed oil on milk conjugated linoleic acid and omega-3 fatty acids content /." Available to subscribers only, 2007. http://proquest.umi.com/pqdweb?did=1456286001&sid=2&Fmt=2&clientId=1509&RQT=309&VName=PQD.
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Tadayyon, Ali, Sedigheh Beheshti, and Mohammad Pessarakli. "Effects of sprayed humic acid, iron, and zinc on quantitative and qualitative characteristics of niger plant ( Guizotia abyssinica L.)." Taylor & Francis, 2017. http://hdl.handle.net/10150/626135.
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In order to investigate the effect of foliar application of organic fertilizer and micronutrients on
quantitative and qualitative characteristics of Niger plant, a field experiment was conducted in a complete randomized block design with three replications at Shahrekord University Research
Farm during the years 2013-2014. Treatments included three levels of humic acid (1, 3, and 6
liters of humic acid per hectare), iron (4 parts per million, ppm), zinc (4 parts per million, ppm) and control (without humic acid iron, and zinc). In this experiment, traits of the number of heads
per plant, seeds number per head, 1000 seeds' weight, grain yield, and also oil and protein
content were evaluated. The findings showed that foliar application of humic acid, zinc and iron
resulted in a significant increase in all analyzed traits. The most significant plant response was
obtained with the use of 6 liters humic acid per hectare, and the second most significant plant
response was seen with the sprayed zinc treatment which was probably due to limited absorption and deficiency of these elements in the tested soil.
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Imhof, Nadine-Christine. "Fish oil: role in development and healing of experimental ulcers in the rat /." [S.l : s.n.], 1993. http://www.ub.unibe.ch/content/bibliotheken_sammlungen/sondersammlungen/dissen_bestellformular/index_ger.html.
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Kaur, Harjeevan. "Influence of Bna.FAD2 alleles on the erucic acid and polyunsaturates content in Brassica napus oil." Thesis, University of York, 2018. http://etheses.whiterose.ac.uk/22243/.
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Brassica napus L. (rapeseed) is an economically important oilseed crop worldwide, having uses in both food and non-food sectors. Its industrial applications are linked to the natural occurrence of erucic acid (EA, C22:1), together with other fatty acids in its seeds. EA is a valuable fatty acid that could be derived into products such as erucamide, brassylic acid and pelargonic acid having a wide range of industrial applications such as plasticizers, slip additives, lubricants, pharmaceuticals, biodiesel and many more. EA biosynthesis is controlled by Bna.FAE1s (FATTY ACID ELONGASES 1) in B. napus. In addition, low levels of polyunsaturated fatty acids (PUFAs) are desirable in the oil for the industry as it increases the thermal stability of the oil. PUFAs biosynthesis is controlled by Bna.FADs (FATTY ACID DESATURASES) in B. napus. The present study was aimed to underpin the new loci affecting the EA biosynthesis by using the associative transcriptomics approach and to study the influence of Bna.FAD2 family on the erucic acid (or very long chain fatty acids, VLCFAs) and polyunsaturated fatty acids levels. Although new loci influencing the erucic acid levels were not found from the present study but a unique specification – high erucic acid rapeseed in the low polyunsaturates (HELP) background was developed by introducing partially functional Bna.FAD2 family from EMS mutagenized mutants to the high erucic acid rapeseed background. HELP lines showed the influence of partially functional Bna.FAD2 alleles in the fatty acid compositions, ~8% increase in the erucic acid (60%) and VLCFAs (66%) levels as compared to the parental high erucic parents having functional Bna.FAD2 family. Polyunsaturates content of less than 7% was found in these HELP lines. HELP oil is anticipated to be a valuable industrial oil that could contribute significantly to reduce the processing costs and serve as a renewable environment-friendly industrial resource with no toxicity.
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Aflatuni, A. (Abbas). "The yield and essential oil content of mint (Mentha ssp.) in Northern Ostrobothnia." Doctoral thesis, University of Oulu, 2005. http://urn.fi/urn:isbn:9514277465.
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Abstract
Peppermint (Mentha x piperita L.) oil is one of the most popular and widely used essential oils, mostly because of its main components menthol and menthone. Peppermint oil is used for flavouring pharmaceuticals and oral preparations. Corn mint is the richest source of natural menthol. Carvone-scented mint plants, such as spearmint (M. spicata), are rich in carvone and are widely used as spices, and they are cultivated in several countries. Studies were made into the yield and essential oil content of several mint species and the original. The general aim of the work was to examine the optimal conditions for cultivating mint in Northern Finland. The specific aims of the study were (first) to investigate the differences in the oil content for several mint species and (secondly) to compare the effect of various factors such as plant spacing (10, 20 and 30 × 50 cm), liming (0, 4, 8, 12 and 16 tons ha-1), propagation methods (micropropagated and conventionally propagated plants) and harvest date (once at the end of August in comparison with first cut at the beginning of August and second cut in mid September) on the cultivation success, quality and quantity of the plants. The constituents of the essential oil were analysed from leaf samples using GC-MS.
Among the peppermints of different origins studied, peppermint of USA and Egypt origin ('Black Mitcham') contain the highest menthol and optimum oil yield. Corn mint and Sachalin mints both had high menthol content. Due to several reasons, such as no significant differences between the different densities and oil composition, markedly higher amount of weeds at 30 × 50 cm than at 10 × 50 and 20 × 50 cm spacing and the high seedling costs and the danger of fungi and disease at a 10 × 50 cm spacing, a plant optimum of 20 × 50 cm spacing is recommended for Northern Ostrobothnia. If the pH value is lower than 6, or levels of Mg and Ca are low, liming at a rate of 4–8 t ha-1 for sandy soils in Finland is recommended in order to achieve higher fresh and oil yields. In the first year, there were no differences in the dry leaf yield of micropropagated and conventionally propagated plants, but the menthol content was significantly higher in conventionally than in micropropagated plants. In the second year, only the dry leaf yield of micropropagated plants was higher than that of their conventionally propagated counterparts. Cutting peppermint only once during full bloom (the end of August) gives the maximum oil yield of good quality. In conclusion, it is possible to achieve as high as or even higher oil quality and dry yield in North Ostrobothnia than it is in central Europe or south Asia. However, this requires observing certain cultivation factors such as having the right type of mint, soil pH, planting density, harvesting time and propagation method In addition, mints must be cultivated in the same place for only two and a maximum for three years.
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Elahi, Nosheen. "The potential of using the BnLEC1 and BnFUSCA3 genes to manipulate oil content in Brassica napus L." Elsevier-Plant Physiology and Biochemistry, 2015. http://hdl.handle.net/1993/31841.
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Due to the immense utilization in food and industry, there is enormous commercial and scientific interest to manipulate canola (Brassica napus L.) seed oil. Seed oil accretions are influenced by genes involved in embryo and seed development. FUSCA3 (FUS3) and LEAFY COTYLEDON1 (LEC1) are well-known transcription factors involved during seed and embryo development. The main objective of this project was to evaluate the role of these genes during seed storage deposition and microspore-derived embryogenesis in B. napus. For this purpose, six BnLEC1 transgenic lines and three BnFUS3 TILLING mutant lines were generated. The over expression of BnLEC1 significantly increased the seed oil content, while the down regulation of BnLEC1 or mutation of BnFUS3 reduced the level of seed oil. Experimental alterations of BnLEC1 and BnFUS3 triggered transcriptional modifications in enzymes taking part in sucrose transport and metabolism, glycolysis, and fatty acid (FA) biosynthesis. These changes are suggestive of a greater carbon pool to FA biosynthesis in tissues over-expressing BnLEC1, and a reduced carbon flux available for the synthesis of FA in BnLEC1 down regulators and BnFUS3 tilling mutants.
While the elevated oil content induced by BnLEC1 was not accompanied by alterations in FA composition, oil nutritional value, or glucosinolate (GLS) levels, suppression of BnLEC1 reduced seed oil accumulation and raised levels of GLS, possibly through the transcriptional regulation of BnST5a (Sulphotransferase5a), the last GLS biosynthetic enzyme. BnFUS3 tilling mutant seeds had increased levels of linoleic acid, possibly due to the reduced expression of ω-3 FA DESATURASE (FAD3). The effects of altered expression of BnLEC1 and BnFUS3 were also assessed during microspore-derived embryogenesis. Substantial structural abnormalities, accompanied by changes in transcript levels of several embryo marker genes were observed in embryos in which the expression of BnLEC1 or BnFUS3 was altered. The changes in oil level and FA profiles observed in the transformed microspore-derived embryos followed a similar trend to that described in seeds. Collectively, these observations suggest that manipulation of BnLEC1 and BnFUS3 can be employed as a tool to enhance seed oil production and quality in B. napus.February 2017
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Al-Bakri, Ahmed N. "ASSESSMENT OF OIL QUANTIFICATION METHODS IN SOYBEAN AND CHIA SEEDS AND CHARACTERIZATION OF OIL AND PROTEIN IN MUTANT CHIA (SALVIA HISPANICA L.) SEEDS." UKnowledge, 2017. http://uknowledge.uky.edu/pss_etds/93.
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This thesis includes two main parts:
I. Evaluation of techniques for oil (total lipid) quantification of chia and soybean seeds.
This study evaluated ten different methods of seed oil quantification, including some methods that have not been applied to oilseeds before. The main aim of this study was to find one or more techniques that are easy, inexpensive, safe and fast with a small amount of ground seeds. The Soxhlet method was used as a standard to compared between techniques of oil quantification. The oil extraction by the Soxhlet method was evaluated with two solvents petroleum ether and acetone. There is not a statistically significant difference between petroleum ether and acetone solvents. No significant differences for the amount of oil recovered via the Soxhlet method were found between Medium Moisture Content (MMC > 10%) and Low Moisture Content (LMC < 4.0 %). The Folch technique provided higher percentages of oil extraction than Bligh and Dyer and hexane-isopropanol techniques. There is not a statistically significant difference (P =0.0844) between Soxhlet method and Folch method but less than the Soxhlet method. A supercritical fluid extraction (HCH) method provided a lower yield of oil extraction compared with the Soxhlet method for three varieties of bias samples. A Direct Transesterification (DT) method with LMC and MMC provided a statistically significant difference than the Soxhlet method. The DT with LMC produced higher yield than DT with MMC between samples but lower than the Soxhlet method. A Double Direct Transesterification (DDT) following Griffiths protocol provided more accurate results with the stir bar technique than sonication technique. 11 oilseeds bias samples (10 bias samples of soybean and one of chia) covering an oil content range of 15.4 to 32.6% showed, there is a significant difference between the Soxhlet and DDTG method and high oil quantification found with DDTG. A Double Direct Transesterification following Qiao et al. (2015) provided similar oil extraction to the Griffiths et al. (2010) method and also there is a significant difference between the Soxhlet and DDTQ method and higher oil recovered with DDTQ. The Bead Beating Extraction (BBE) protocol showed, there is a statistically significant difference ( P< 0.001) than the Soxhlet method. The BBE provided high oil quantification comparing with the Soxhlet method. The BBE provided the best results since it is the easiest, cheapest and fastest oil quantification method. A Nile red fluorescence technique yield no clear results.
II. Characterization of oil and protein in mutant chia (Salvia hispanica L.) seeds.
The objectives of this study were to (1) measure heritability in chia plants of levels of oil and protein content and seed yield and (2) Compare differences between two locations over two years for oil and protein percentages in chia and seeds yield. A population of 180 M3 mutant individual chia plants was harvested and for which forty M4 chia seeds were planted based on seed composition characteristics, with six plants representing each characteristic (high and lower oil, protein, and density and high yield). The forty M4 chia seeds were planted, with two replications for two locations, have been chosen in Kentucky one on Spindletop farm and the other in Quicksand farm. The M5 progeny seeds from plants grown in Spindletop and Quicksand contained significantly (P < 0.05) more protein than did seeds from the M4 parents. There were significant differences (P < 0.05) between locations where Quicksand obtain higher oil content than Spindletop. There was no significant difference between M5 parents seeds and M4 progeny seeds and higher yield kg/ha at Quicksand than Spindletop.
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McDonald, Jeff. "An exploratory study of localisation drivers and barriers of oil and gas service firms : a case study approach." Thesis, Robert Gordon University, 2017. http://hdl.handle.net/10059/2465.
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The purpose of this thesis is to explore and understand the ‘localisation’ phenomenon from a geographical, cultural, technical and governmental theme to help explain why the level of local content in the oil and gas engineering and technical services private sector tends to flatten out at specific engineering and management skillsets in order to balance quality and delivery of the service and maintain operational excellence. Five research objectives were developed to achieve the research aim to provide a clear understanding, from a corporate strategic perspective, of the drivers and perceived barriers to successful localisation. For the purposes of this thesis, the term "localisation" is understood to mean “when a local national is filling a required job sufficiently competently to fulfil organisational needs” (Potter 1989). Due to the nature of investigation, this study adopted a qualitative inquiry. Thus, a mix of qualitative data collection methods were used such as document, experienced observation, and interviews with senior managers at the corporate strategic level of the business. An interview guide was developed from a conceptual framework generated from the literature review. The study targeted an ‘elite’ sample of oil and gas executives/ managers who are considered role models in the case study organisation. This study argues that a form of grounded theory/qualitative inquiry is adopted during data analysis using open, axial, and selective coding, leading to an evolved conceptual framework of localisation drivers and barriers. In addition to a thematic analysis, an integrated view from the researcher as an experienced observer resulted in a validated conceptual framework. This framework provides a holistic set of factors that must be considered, and understood, from a corporate strategic perspective as being directly influential in achieving successful localisation of a subsidiary part of the business. It is found that four of the five objectives were met and objective five partially achieved which identified an opportunity for further research to investigate and develop weightings across the four localisation barrier themes to determine an optimised balance of cost, delivery, and local content to maintain the desired operational excellence in the oil and gas services contractor industry. The study appears to have a contribution to knowledge through the evolving conceptual framework of localisation and provides the first holistic view of both localisation drivers and barriers relevant to oil and gas services contractors. A methodological contribution is worth noting since the researcher acted as an experienced observer during the process of this research. No doubt, industrial experience of the research and his access to the senior management has been one of the key contributing factors to a successful completion of the study. Finally, one can argue that this study has made contribution to the policy makers who provided access to the researcher. The findings of this study will provide a better and clear understanding of localisation and its drivers and barriers.
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Afaneh, Ibrahim Abdullah. "Immersion frying of potato products." Thesis, Queen's University Belfast, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.343110.
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Akhzari, Davoud, and Mohammad Pessarakli. "Effect of Drought Stress on Total Protein, Essential Oil Content, and Physiological Traits of Levisticum Officinale Koch." Taylor & Francis, 2015. http://hdl.handle.net/10150/615121.
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Levisticum officinale Koch is one of the most important plants producing essential oil. An experiment was conducted to determine the effect of drought stress on growth, total protein and essential oil content of Levisticum officinale. The experiment was conducted in a greenhouse, in a completely randomized design using 5 replications. Aridity levels of field capacity irrigation (as control), −0.6 and −1.0 MPa were applied. There was significant effect of aridity on leaf area in Levisticum officinale. The highest leaf area values were found in the lowest aridity (FC) level. The root weight and root length in the −0.6 MPa aridity level were more than that of the control aridity level, but, shoot height and shoot weight were highest in the control treatment. Total soluble protein contents under −0.6 MPa drought stress was numerically lower than that in the control treatment, but statistically there was no significant difference between protein contents in the −0.6 MPa and the control treatment. Compared to the control treatment, total soluble protein contents of Levisticum officinale were significantly decreased in the −1.0 MPa drought treatment. Essential oil content of Levisticum officinale was significantly increased in the −0.6 MPa drought treatment compared to the control. Compared to control treatment, there was a significant reduction found in essential oil content of Levisticum officinale in the −1.0 MPa aridity treatment. The results suggest that in the drought levels between −0.6 to −1.0 MPa, Levisticum officinale could be used for arid and semi-arid lands economical use.
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Obi, Chuka Obinna. "Local content development in the Nigerian oil and gas industry : why it is not succeeding? / C.O. Obi." Thesis, North-West University, 2008. http://hdl.handle.net/10394/2645.
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This research focuses on human capacity development in the Nigerian oil and gas industry. The need for local capacity building in this industry is imperative because oil and gas proceeds are the major source of foreign exchange earnings for the country. Oil has been exploited in Nigeria for over five decades and there is still relatively poor local participation and hence the need for this research. The idea is to encourage local participation so as to promote economic growth and industrial development.
This research identifies reasons for the ineffective implementation of the Nigerian content policy and will develop a framework that will address holistically the factors needed to ensure industrial growth through proper implementation and particular attention is paid to specific factors that enhance participation of local firms in the oil and gas industry.
The experience of Norway will be used as a case study to demonstrate the means by which they were able to achieve domestically based industrial competence while exploiting their petroleum resources and also the necessary conditions that was in place that encouraged proper exploitation of their resources.Thesis (M.Ing. (Development and Management Engineering))--North-West University, Potchefstroom Campus, 2009.
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Ayanoore, Ishmael. "Oil governance in Ghana : exploring the politics of elite commitment to local participation." Thesis, University of Manchester, 2018. https://www.research.manchester.ac.uk/portal/en/theses/oil-governance-in-ghana-exploring-the-politics-of-elite-commitment-to-local-participation(b3befa8b-3bf0-480b-b798-2df76a7b6863).html.
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This thesis explores the politics of elite commitment to promote local content and participation within Ghana's oil and gas sector. Since Ghana discovered commercial quantities of oil in 2007, debates over whether it would avoid the 'resource curse' have primarily taken place within a neo-institutionalist frame of analysis that emphasises the importance of establishing certain types of institutional arrangements which can help constrain and shape elite commitment to developing petroleum resources in the national interest. This thesis seeks to go beyond this framing by deploying new forms of political analysis which show that elite commitment is shaped not by institutions but by the wider configuration of power. It employs an extended 'political settlements' framework (incorporating ideas) that explains how elite interests and ideas shape developmental forms of political commitment to governing oil in the national interest. The analysis is based on three main cases - the politics of formulating and adopting local content legislation, the process through which this legislation was implemented and the effort put into building the capacity of Ghanaian firms to participate in the sector. The thesis argues that the underlying tendencies within Ghana's competitive clientelist political settlement (electoral incentives, coalition building, patronage politics and ideas) directly shaped the levels of political commitment to secure greater oil rents. Ghana's competitive political settlement generated incentives for politicians to use local content policy promises as a strategy to bring certain civil society and private sector elites within what would become a ruling coalition. This move, along with the resource nationalist ideology of the coalition in power at the time, in turn helped to generate relatively high levels of elite commitment to developing ambitious targets within the legislation. However, the process of implementation has been shaped more directly by incentives than ideas, particularly in terms of pressures to distribute participation opportunities in line with the clientelist logic of the political settlement, benefitting politically connected firms. In applying an extended political settlements approach, this thesis offers deeper political economy insights into the drivers of elite commitment to governing oil in the national interest, and shows how Ghana's efforts to avoid the resource curse have and will continue to be closely shaped by 'power relations', 'elite bargaining' and 'ideas'.
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Lyons, Benjamin A. "Contesting the Mainstream? Citizen News Platforms, the Alternative Paradigm, and the BP Oil Spill." OpenSIUC, 2013. https://opensiuc.lib.siu.edu/theses/1321.
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With emerging content forums blurring the distinctions between journalistic paradigms, this study helps illuminate those which best promote alternative practice. A content analysis of Deepwater Horizon oil spill coverage compared three platforms for online citizen journalism: corporate (CNN iReport), alternative (Indymedia), and independent blogs. News stories were coded for sources, links, author-reader interaction, mobilizing information, tone for the liable parties' ability and intent in handling the disaster, and contestation of official information. Results show that Indymedia was the most alternative in inclusion of mobilizing information, critical tone, contestation of mainstream versions, ratio of alternative links to mainstream, and total usage of alternative sources. iReport engendered the greatest rates of community via interaction, while also averaging the highest ratio of alternative sources. The blogs split on nearly all metrics, as one rated highly in every category and the other near last. This analysis determines which platforms are most likely to cultivate disaster news that stands as alternative to, and not extension of, the mainstream. This study makes a contribution to the theory of alternative media and is the first to compare citizen journalism sites against one another in measuring their adherence to the alternative paradigm, and its examination of CNN's citizen-report model also represents a novel contribution. The findings discussed may help direct citizens as they reach out to online communities in times of disaster.
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Banks, Scott. "Ash control methods to limit biomass inorganic content and its effect on fast pyrolysis bio-oil stability." Thesis, Aston University, 2014. http://publications.aston.ac.uk/23181/.
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This research investigates specific ash control methods to limit inorganic content within biomass prior to fast pyrolysis and effect of specific ash components on fast pyrolysis processing, mass balance yields and bio-oil quality and stability. Inorganic content in miscanthus was naturally reduced over the winter period from June (7.36 wt. %) to February (2.80 wt. %) due to a combination of senescence and natural leaching from rain water. September harvest produced similar mass balance yields, bio-oil quality and stability compared to February harvest (conventional harvest), but nitrogen content in above ground crop was to high (208 kg ha.-1) to maintain sustainable crop production. Deionised water, 1.00% HCl and 0.10% Triton X-100 washes were used to reduce inorganic content of miscanthus. Miscanthus washed with 0.10% Triton X-100 resulted in the highest total liquid yield (76.21 wt. %) and lowest char and reaction water yields (9.77 wt. % and 8.25 wt. % respectively). Concentrations of Triton X-100 were varied to study further effects on mass balance yields and bio-oil stability. All concentrations of Triton X-100 increased total liquid yield and decreased char and reaction water yields compared to untreated miscanthus. In terms of bio-oil stability 1.00% Triton X-100 produced the most stable bio-oil with lowest viscosity index (2.43) and lowest water content index (1.01). Beech wood was impregnated with potassium and phosphorus resulting in lower liquid yields and increased char and gas yields due to their catalytic effect on fast pyrolysis product distribution. Increased potassium and phosphorus concentrations produced less stable bio-oils with viscosity and water content indexes increasing. Fast pyrolysis processing of phosphorus impregnated beech wood was problematic as the reactor bed material agglomerated into large clumps due to char formation within the reactor, affecting fluidisation and heat transfer.
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Benin, Papa. "Human Resource Local Content in Ghana's Upstream Petroleum Industry." ScholarWorks, 2017. https://scholarworks.waldenu.edu/dissertations/3385.
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Enactment of Ghana's Petroleum (Local Content and Local Participation) Regulations, 2013 (L.I. 2204) was intended to regulate the percentage of local products, personnel, financing, and goods and services rendered within Ghana's upstream petroleum industry value chain. Five years after the inception of Ghana's upstream oil and gas industry, a gap is evident between the requirements of L.I. 2204 and professional practice. Drawing on Lewin's change theory, a cross-sectional study was conducted to examine the extent of differences between the prevailing human resource local content and the requirements of L.I. 2204 in Ghana's upstream petroleum industry. The extent to which training acquired by indigenous Ghanaians seeking jobs in Ghana's oil fields affects the prevalent local content in its upstream petroleum industry was also examined. Survey data were collected from 97 management, technical, and other staff in 2 multinational petroleum companies whose oil and gas development plans have been approved by the Petroleum Commission of Ghana. To answer the research questions and test their hypotheses, one-way ANOVA was performed with staff category (management, technical, and other) as the independent variable and prevalent local content as the dependent variable. Results indicated that prevailing local content in Ghana's upstream petroleum industry meets the requirements of L.I. 2204. Further, training acquired by indigenous Ghanaians seeking jobs in Ghana's oil fields affects the prevalent local content in its offshore petroleum industry. Findings may encourage leaders within multinational oil companies and the Petroleum Commission of Ghana to organize educational seminars that equip indigenous Ghanaians with specialized skills for working in Ghana's upstream petroleum industry.
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Croat, Samantha Jo. "Phosphorus Dynamics and Crop Productivity in Bakken Crude-Oil Remediated Soils." Thesis, North Dakota State University, 2018. https://hdl.handle.net/10365/29169.
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Thermal desorption (TD), a remediation method used to remove hydrocarbons from contaminated soils, may cause changes in soil properties that threaten soil function and plant productivity. The goal of this research is to better understand the effect that TD treatment has on soils intended for agricultural use. A series of soil phosphorus (P) sorption and desorption experiments were conducted on soils before and after TD treatment to determine P availability for plant uptake and risk for run-off. TD-treated soils retained more P, likely due to mineral transformations of Fe- and Al-oxides. In addition, a three-year field study using mixtures of topsoil (A), crude-contaminated soil (SP), and TD-treated soils (TDU) was conducted. Yields were significantly greater in plots that included A in the mixture compared to SP and TDU soils alone. TD-treated soils can be a replacement for topsoil, but the addition of topsoil will reduce the time to successful reclamation.
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Oguagha, Udechukwu Offordile. "A critical evaluation of the effectiveness of local content policy (LCP) and transparency practices in LCP implementation in the Nigerian oil and gas industry." Thesis, Robert Gordon University, 2017. http://hdl.handle.net/10059/2742.
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One of the aims of the Local Content Policy (LCP) is the economic development of Nigeria through the utilisation of local personnel and resources in the activities of the Nigerian oil and gas industry. Many studies have investigated the LCP, but limited work has been undertaken in investigating the transparency practices involved in the implementation of the LCP in the Nigerian oil and gas industry. The study critically evaluates the effectiveness of the LCP and the transparency practices associated with its implementation. A conceptual framework based on accountability was developed and employed in designing the research instrument. This framework was underpinned by the institutional theory, which links accountability discourse to regulatory institutions where organisations within a particular field are subject to pressures to exhibit legitimacy through socially and culturally authorised administrative routines that are intended to render accountability. The study employed a qualitative methodology and the data was collected through in-depth semi-structured interviews with respondents from twenty-three indigenous oil and gas companies, regulatory bodies, international oil and gas companies and non-governmental organizations. The research findings demonstrate that the various LCP stakeholders’ views on the definition and purpose of the LCP differ significantly. These diverse opinions affect the way in which the LCP is perceived and implemented in the oil and gas industry. The study has been instrumental in revealing a number of positive effects the LCP has generated since its implementation in the Nigerian oil and gas industry. For example, the LCP compelled IOCs to utilise local resources in their operations, resulting in the domestication of oil and gas activities. However, the findings also reveal that the LCP has been enforced despite the lack of local capacity and capability for its implementation. The findings, therefore, highlight a number of challenges associated with LCP implementation including: the lack of infrastructure; insufficient capital and manpower; absence of trust; and the lack of coordination between the regulatory agencies in the industry. The research findings also reveal that there are different levels of transparency in the implementation of LCP. Determination of the level of transparency in LCP implementation and compliance monitoring is at the discretion of the NCDMB and the oil and gas companies, which unfortunately facilitates corrupt practices. Therefore, this study argues that significant improvements are required in transparency practices in LCP implementation by strengthening the LCP’s monitoring and enforcement process. Further, enforcement should strictly be the responsibility of the NCDMB, with no interference from the Nigerian government. Some further recommendations arising from this research include the need for investment in infrastructure that will facilitate indigenous companies’ participation in the industry. Also, efforts should be made to promote partnership and collaboration between indigenous companies and IOCs, encouraging investment in world-class infrastructure that can compete with international standards. To foster this partnership, the government and IOCs must invest in educational institutions which could boost the knowledge and capacity of Nigerians. The research concludes with the development of two new models: (1) The LCP stakeholder perception model; and, (2) The LCP implementation model. These models, which are the main contributions of knowledge arising from this thesis, will potentially aid the effective implementation of the recommendations arising from this study.
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De, Villiers Chris Johan. "The effect of Phosphorus on the growth, plant mineral content and essential oil composition of Buchu (Agathosma betulina)." Thesis, Link to the online version, 2007. http://hdl.handle.net/10019.1/1867.
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Cerven, Vasile. "EFFECT OF NITROGEN, LOCATION, AND HARVESTING STAGE ON PEPPERMINT (Mentha X piperita L.) PRODUCTIVITY, OIL CONTENT, AND COMPOSITION." MSSTATE, 2009. http://sun.library.msstate.edu/ETD-db/theses/available/etd-03232009-123049/.
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Peppermint dry weight biomass was higher in Verona (8119 kg/ha) than in Stoneville (6115 kg/ha). Overall both, oil content and yield were higher in bud formation stage than flowering stage. The levels of major essential oil constitutes were (-)-menthol 26 30 %, (-)-menthone 14 21 %, (+)-menthofuran 5 11 %, and eucalyptol 3 4 % of total essential oil content at flowering stage. Menthone content and its yield were higher at first cut; however, (+)-menthofuran content and its yield were higher at the second cut at bud formation. Although N fertilizers at rate 80 kg/ha did not affect essential oil content and yield at cut 1, N rate at 80 + 80 kg/ha increased oil yield at cut 2.
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Himstedt, Samuel Ross. "Oil content and other components as indicators of quality and shelf life of macadamia kernels (maiden and betche) /." St. Lucia, Qld, 2002. http://www.library.uq.edu.au/pdfserve.php?image=thesisabs/absthe16555.pdf.
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Zhao, Jianyi. "QTLs for oil content and their relationships to other agronomic traits in an European x Chinese oilseed rape population." Doctoral thesis, [S.l.] : [s.n.], 2002. http://deposit.ddb.de/cgi-bin/dokserv?idn=967138183.
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Nguyen, Jason P. "The effect of a diet supplemented with flaxseed oil on the lipid content and fatty acid profile of rainbow trout (Oncorhynchus mykiss) muscle tissue." Morgantown, W. Va. : [West Virginia University Libraries], 2006. https://eidr.wvu.edu/etd/documentdata.eTD?documentid=4777.
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Thesis (M.S.)--West Virginia University, 2006.Title from document title page. Document formatted into pages; contains v, 33 p. : ill. (some col.). Includes abstract. Includes bibliographical references (p. 30-33).
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Masciola, David A. "Effects of feed oil content, transmembrane pressure and membrane rotational speed on permeate water quality in high-shear rotary ultrafiltration." Morgantown, W. Va. : [West Virginia University Libraries], 1999. http://etd.wvu.edu/templates/showETD.cfm?recnum=465.
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Thesis (M.S.)--West Virginia University, 1999.Title from document title page. Document formatted into pages; contains x, 128 p. : ill. (some col.). Includes abstract. Includes bibliographical references (p. 123-128).
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Aykas, Didem P. "The Effect of Temperature, Lecithin Content, Voltage, Resistivity, Viscosity, and Surface Tension on Droplets/cm² During Electrostatic Spraying of Oil." The Ohio State University, 2012. http://rave.ohiolink.edu/etdc/view?acc_num=osu1330588156.
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Khattak, Farina Malik. "Fatty acid profiles and oxidative stability in tissue from chicks fed diets varying in oil and glucosinolate type and content." Thesis, University of Aberdeen, 1997. http://digitool.abdn.ac.uk/R?func=search-advanced-go&find_code1=WSN&request1=AAIU528929.
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Four experiments were carried out to investigate the effects of glucosinolates, the level and type of dietary fat and -tocopherol acetate (ATA) supplementation on broiler performance, fatty acid composition, oxidative stability of tissues and immunological changes in the caecal crypts and bone marrow cells. In Experiment 1, 270 chicks were fed diets containing either whole full-fat rape seed (FFR) with a glucosinolate content of 14.4 mmol/kg or marine oil (MO) calculated to provide 40 and 120 g fat/kg diet. At each level of fat in the diet ATA was supplied at 20 and 300 mg/kg diet. Data presented in this study indicate that whole FFR (low glucosinolate) and MS(high glucosinolate) at the level of 300 and 50 g/kg respectively can be consumed by broiler chicks without any detrimental effects. Birds fed diets containing low glucosinolate MuO, RO, and RSM showed similar performance to those of birds fed the soya based control diets. The data showed that fatty acid composition of tissue lipid can be manipulated to varying degrees of changing the fatty acid composition of dietary lipid. Tissue monounsaturated fatty acid (MUFA) and n3 fatty acid proportions were increased and n6:n3 ratio was decreased by feeding diets containing FFR, MS, MuO, RO and RSM, Supplemental ATA increased the -tocopherol content of blood serum and improved the stability of tissue lipid to oxidation when used at the level of 300 mg/kg diet. Inclusion of enzyme treated FFR and RSM in broiler diets improved weight gains and reduced the caecal irritation caused by contents of the diet. Cells identified in the caecal crypts and bone marrow tissue showed a potential for determining the immunological responses of birds to various diets.
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Ado, Rabiu. "Accounting, accountability and governance in upstream petroleum contracts : the case of local content sustainability in the Nigerian oil and gas sector." Thesis, Robert Gordon University, 2016. http://hdl.handle.net/10059/1586.
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Local Content is an oil sector governance and sustainability policy that aims at check-mating the dominance of the foreign oil companies in host countries, and encouraging the participation of the local oil firms in the petroleum value-chain. It is a burgeoning concept applied in the upstream petroleum contracts in the developing petro states. This study was conducted to examine the local content accounting, accountability and governance of the Nigerian Content Development and Monitoring Board (NCDMB) and the five major International Oil Companies (IOCs) operating in Nigeria (Shell, Chevron, ExxonMobil, Total and Agip). The soft and hard accountability of the two principal actors were determined. The work drew on the Chatham House Guidelines for Good Governance in Emerging Oil and Gas Producers (2013) to derive its conceptual and analytical models. The study used the convergent parallel design and a combination of the three accounting paradigms to draw its conclusions. Thematic analysis, descriptive and inferential statistics including the post hoc Kruskal-Wallis and Mann-Whitney tests with Bonferroni Corrected Alpha, and the logistic regression tests were used. The study also applied the mechanistic content analysis methodology on fifty sustainability reports of the selected IOCs in line with the Global Reporting Initiative (GRI) and the International Petroleum Industry Environmental Conservation Association (IPIECA) sustainability reporting guidelines. Disclosure index and paired-samples t-test were used to determine the existence and trends in the IOCs’ local content disclosure practices before and after the enactment of the Nigeria’s local content law. The study found the local content policy to be an accountabilitybased sustainability driver in the Nigerian petroleum sector. Although the NCDMB’s performance was favourable to a large extent, the study found that corruption, fronting, and non-disclosure of the beneficial ownership of some oil firms remained the major challenges of local content in Nigeria. An expectation gap between the Board and the stakeholders on the financial accountability was established. The study found moderate and consistent local content disclosure indices of the periods before and after the Nigeria’s local content law, but higher volumetric disclosure in the period after the law, signifying likely impact of the local content law on the IOC’s voluntary disclosure. It was recommended that the Board should tighten up its regulatory responsibilities and avoid questionable practices. It was also suggested that the Nigerian local content rules should incorporate more incentives such as unringfencing and crossfencing of upstream costs to encourage more investment. The study also suggested that the accounting standard-setting bodies should issue dedicated accounting standards or expand the existing IFRS 8 and IAS 21 to comprehensively address the preparation and presentation of local content information in the annual financial statements.
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Scott, Karen Christine. "The effect of processing on the vitamin D?, vitamin E, pre-vitamin D?, and pro-vitamin D? content of menhaden fish meal, and on the lipid-soluble vitamin content of menhaden fish oil : and the selenium content of various tissues... /." The Ohio State University, 1989. http://rave.ohiolink.edu/etdc/view?acc_num=osu1487675687176151.
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Melaku, Eneyew Tadesse. "Evaluation of Ethiopian nigerseed (Guizotia abyssinica Cass) production, seed storage and virgin oil expression." Doctoral thesis, Humboldt-Universität zu Berlin, Landwirtschaftlich-Gärtnerische Fakultät, 2015. http://dx.doi.org/10.18452/17130.
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Das Ziel der experimentellen Arbeit war die Untersuchung der Einflussfaktoren auf den Ertrag, die Saatgutqualität unter verschiedenen Lagerungsbedingungen sowie die Effizienz der Expression vonRamtillkraut (Guizotia abbysinica Cass.). In Feldversuchen wurden folgende Varianten untersucht, Sorten ‚Fogera‘ und ‚Kuyu‘, Saatgutaufwand von 5, 10, 15 kg ha-1, ein Stickstoffaufwand von 13, 23 und 33 kg ha-1, sowie eine differenzierte Wasserversorgung an zwei Standorten (Adet und Koga). In Adet wurde der höchste Saatgut Ertrag mit 1.384,60 kg ha-1 ermittelt, Erträgen in Koga (ohne Bewässerung) mit 1.064,72 kg ha-1 und 967,00 kg ha-1 (mit Bewässerung). Der höchste Ölgehalt wurde im Saatgut aus Koga (ohne Bewässerung) mit 41,54% ermittelt, gefolgt von Koga (mit Bewässerung) 39,59% und Adet mit 38,67%. Signifikante Unterschiede wurden zwischen den N-Aufwandmengen in Koga mit Bewässerung und Saatgutmengen in Adet ermittelt. Die Unterschiede bei den Fettsäuregehalten in Adet waren nicht signifikant. Der Alpha-Tocopherol Gehalt betrug 80 mg pro 100 g bei hoher Saatdichte und hoher N-Düngung. Hinsichtlich des Verfahrens des Ölpressens, wurde ein signifikanter Unterschied zwischen Effizienz und Temperatur ermittelt. Die Dauer der Konditionierung und die Vorschubgeschwindigkeit sind negative korreliert gleichfalls mit der Effizienz der Expression. Die Temperaturen von 70°C und 80°C zeigten keinen signifikanten Einfluss auf die Ölausbeute, dagegen war der der Einfluss von 90°C statistisch signifikant.The aim of this study was to investigate factors influencing seed yield, postharvest handling, and the oil expression efficiency for nigerseed (Guizotia abbysinica Cass.). Based on field study on two varieties, two locations, three seed rates and three fertilizer rates the highest mean nigerseed yield was 1384.6 kg ha-1 at Adet location (rain fed) followed by location Koga (rain) with 1064.7 kg ha-1 and Koga (irrigation) with 967.0 kg ha-1 showing significant difference. The oil content by location was 41.54% for Koga (rain) followed by 39.59 and 38.67% for Koga (irrigation) and Adet (rain) respectively showing significant difference whereas the Ash content showed a reverse trend of oil content. Fatty acid composition did not show significant difference in any treatment. Significant mean alpha-tocopherol of 80 mg/100 g (70 to 89 mg/100 g) was attained for increasing seed and nitrogen rates. Based on two temperatures and seven relative humidities model evaluation and monolayer moisture content estimation, Guggenheim-Anderson-de Boer (GAB) models was found to best suit both varieties as compared to Brunauer-Emmet-Teller (BET), and modified Chung &Pfost. For oil expression efficiency, 90ºC seed conditioning showed significant effect compared to 80 and 70ºC however conditioning times and feed rates did not differ significantly.
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Wälimaa, Peter. "Vad är Peak Oil och existerar det? : En kritisk lingvistisk av tryckta svenska medier." Thesis, Umeå universitet, Institutionen för kultur- och medievetenskaper, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-67729.
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The purpose of this study is the reports of Peak Oil in Swedish newspapers. In otherwords, how do the news portray or describe the concept and what sources are usedwhen writing articles. With this in mind, I have studied eight published articles in threeSwedish newspapers, Dagens Nyheter, Dagens Industri and Svenska Dagbladet. To studythese articles I've used a qualitative content analysis, as a method, or more specific aCritical Discourse Analysis (CDA). This method was chosen due to it's tools to examinethe text itself and to reveal the structures, unconscious meaning and power of words.Further more I have used theories as agenda-setting (including framing and priming),ideology and newsworthiness to complement the study. The result from the content analysis shows two evident ideologies, one with aneconomic perspective and the other with an environment perspective – with resourcelimitation in mind. The credibility of the sources used depends on who wrote the texts,where both sides tried to be as convincing as possible when presenting their truth andfacts. Overall the environment perspective was portrayed as doomsayers and pessimistswith a greater degree of uncertainty, while the economic perspective was described asoptimists and with certainty. Regarding the sources the paper also shows that in all thearticles confirm and legitimize the power to certain sources. One particular sourcestands out, specifically Kjell Aleklett who is represented in more than half of the articles.One probable reason being that he is an respected scientiest who primarily representsthe resource limitation aswell as the enviroment perspective. Another that journalistsuse certain sources to apper credible, but also let sources with power to keep holding onto it.