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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
41

Parâmetros agronômicos de crambe cultivado no sudoeste do Paraná

Barbizan, Thamiris 07 March 2014 (has links)
O crambe (Crambe abyssinica) apresenta elevado potencial para a produção de biodiesel e é uma alternativa para a segunda safra, cultura de outono/inverno e rotação de culturas. A cultura apresenta diversas características interessantes ao produtor, entre elas: alto teor de óleo na semente, baixo custo de produção, tolerância ao estresse hídrico, rusticidade e precocidade. O objetivo do trabalho foi definir para a região Sudoeste do Paraná o espaçamento e densidade de semeadura além da época de semeadura e seus efeitos sobre a qualidade das sementes, bem como determinar o consumo hídrico e o coeficiente de cultura. Foram realizados quatro experimentos, na Universidade Tecnológica Federal do Paraná – Campus Dois Vizinhos, nos anos de 2012 e 2013, buscando analisar os efeitos da época de semeadura, espaçamento e densidade de cultivo do crambe, o consumo hídrico da planta e análise fisiológica das sementes produzidas. As épocas de semeadura foram de 28 de março a 08 de junho sendo realizados a cada 15 dias. Os espaçamentos de 17 e 51 cm e densidades de 60, 80, 100, 120 e 140 sementes m-2. Foram avaliados os parâmetros produção, germinação, índice de velocidade de germinação, comprimento de plântulas e matéria seca das plântulas. A melhor época observada de semeadura foi a segunda semana de março. Não houve efeito significativo do espaçamento sob a produtividade. As densidades de 100 a 140 sementes m-2, apresentaram os melhores resultados. O Kc foi de 0,64 até o início de florescimento, 0,84 até início da frutificação e 0,79 até início da senescência. / The crambe (Crambe abyssinica) presents itself as a full potential for this end and also it’s a great alternative to the second harvest, the fall/winter´s culture and crop rotations. Crambe shows many good characteristics that are very interesting for the producer, among them are: high concentration of fat in the seed, low production cost, high tolerance to hydric stress, simplicity and precocity. The main objective was to define the spacing and density for the Southwest region of Paraná, and also determine the plantation period as well it´s effects over the quality of the seeds, furthermore the determination of the hydric consumption and culture rate. Four other experiments were conducted at Universidade Tecnológica Federal do Paraná – Campus Dois Vizinhos, in the years 2012 and 2013, seeking to analyze the effects in the plantation period, spacing, density, water consumption and the physiologic analysis of the produced seeds. The planting occurred between March 28th until June 8th each one being planted every 15 days. The spacing were from 17 and 51 cm. and densities of 60, 80, 100, 120 and 140 seeds per m². The analysis of the seed consists in: Germination, index of germination speed, length of the seedlings and dry matter of the seedlings. The best period for both of planting as quality of the production itself was in the second week of March, the spaces did not interfere and the best densities are 100 to 140 seeds per m². The Kc was 0,64 until the blossoming, 0,84 until the fructification and 0,79 until ripeness.
42

Parâmetros agronômicos de crambe cultivado no sudoeste do Paraná

Barbizan, Thamiris 07 March 2014 (has links)
O crambe (Crambe abyssinica) apresenta elevado potencial para a produção de biodiesel e é uma alternativa para a segunda safra, cultura de outono/inverno e rotação de culturas. A cultura apresenta diversas características interessantes ao produtor, entre elas: alto teor de óleo na semente, baixo custo de produção, tolerância ao estresse hídrico, rusticidade e precocidade. O objetivo do trabalho foi definir para a região Sudoeste do Paraná o espaçamento e densidade de semeadura além da época de semeadura e seus efeitos sobre a qualidade das sementes, bem como determinar o consumo hídrico e o coeficiente de cultura. Foram realizados quatro experimentos, na Universidade Tecnológica Federal do Paraná – Campus Dois Vizinhos, nos anos de 2012 e 2013, buscando analisar os efeitos da época de semeadura, espaçamento e densidade de cultivo do crambe, o consumo hídrico da planta e análise fisiológica das sementes produzidas. As épocas de semeadura foram de 28 de março a 08 de junho sendo realizados a cada 15 dias. Os espaçamentos de 17 e 51 cm e densidades de 60, 80, 100, 120 e 140 sementes m-2. Foram avaliados os parâmetros produção, germinação, índice de velocidade de germinação, comprimento de plântulas e matéria seca das plântulas. A melhor época observada de semeadura foi a segunda semana de março. Não houve efeito significativo do espaçamento sob a produtividade. As densidades de 100 a 140 sementes m-2, apresentaram os melhores resultados. O Kc foi de 0,64 até o início de florescimento, 0,84 até início da frutificação e 0,79 até início da senescência. / The crambe (Crambe abyssinica) presents itself as a full potential for this end and also it’s a great alternative to the second harvest, the fall/winter´s culture and crop rotations. Crambe shows many good characteristics that are very interesting for the producer, among them are: high concentration of fat in the seed, low production cost, high tolerance to hydric stress, simplicity and precocity. The main objective was to define the spacing and density for the Southwest region of Paraná, and also determine the plantation period as well it´s effects over the quality of the seeds, furthermore the determination of the hydric consumption and culture rate. Four other experiments were conducted at Universidade Tecnológica Federal do Paraná – Campus Dois Vizinhos, in the years 2012 and 2013, seeking to analyze the effects in the plantation period, spacing, density, water consumption and the physiologic analysis of the produced seeds. The planting occurred between March 28th until June 8th each one being planted every 15 days. The spacing were from 17 and 51 cm. and densities of 60, 80, 100, 120 and 140 seeds per m². The analysis of the seed consists in: Germination, index of germination speed, length of the seedlings and dry matter of the seedlings. The best period for both of planting as quality of the production itself was in the second week of March, the spaces did not interfere and the best densities are 100 to 140 seeds per m². The Kc was 0,64 until the blossoming, 0,84 until the fructification and 0,79 until ripeness.
43

The production of oilseeds in Ethiopia: value chain analysis and the benefit that accrue to the primary producers

Fanta, Elias Gebreselassie January 2005 (has links)
Magister Commercii - MCom / Oilseed is the third most important export item in Ethiopian foreign trade. It has registered a high export growth rate over recent years both in terms of volume and value. Besides its growing share in export, it is widely used for the extraction of edible oil and oilcake that is supplied to the domestic market. Although farmers are the primary producers of oilseeds, they are not able to benefit from the growing market share of the product due to the fact that they find themselves at the end of an extended market chain. As a result they only receive a very small proportion of what the final buyers are paying for the oilseed products. In addition, there is not much experience on the part of the farmers to process oilseeds, change it to edible oil and oilcake and retain the value addition in the local economy. This thesis used the value chain approach to investigate the possibilities for the primary producers to increase their income share from the selling of their products either by directly selling to exporters or by processing oilseeds, producing edible oil and oilcake, and retaining the value addition in the local economy. / South Africa
44

National Dry Bean Nursey Trials in Bonita, 1994

Clark, L. J., Carpenter, E. W. 10 1900 (has links)
Results of the 1994 National Cooperative Dry Bean Nursery Trials are reported in this report Thirty two varieties of eight different classes of beans were included in this replicated, small plot trial Bill-Z, the leading pinto bean variety in the area, was the highest yielding variety with a yield over 4200 pounds per acre. Chase, a pinto variety recently developed with strong rust tolerance, yielded over 4000 pounds per acre. Yields, seed per pound, days to bloom, seed fall duration and yield per day of seed fill are reported in this paper.
45

Planting Date and Nitrogen Fertility Test on Lesquerella in 1993-94

Nelson, J. M., Hart, G. L. 10 1900 (has links)
Lesquerella is a potential crop plant that produces seeds containing hydroxy fatty acids similar to those in castor beans. An important step in the commercialization of this plant for Arizona farms is the development of an efficient agronomic production system. Research on planting dates and nitrogen fertility was conducted at the Maricopa Agricultural Center in the 1991-92, 1992-93, and 1993-94 seasons. Results of the Planting date experiments indicate that early fall planting dates are superior to late fall planting dates in terms of seed yield February plantings appear to be too late for central Arizona production. In all years, lesquerella responded to nitrogen (N) fertilizer. In the 1993-94 test, an application of 54 lbs. N/acre gave a higher seed yield than when no N was applied and the same yield as 108 lbs. N/acre. Additional tests are being conducted to determine optimum timing for N fertilizer applications.
46

The Response of Lesquerella to Nitrogen Fertilizer Rate and Time of Application

Nelson, J. M., Hart, G. L. 10 1900 (has links)
Lesquerella is a plant that grows in the wild in southwestern U.S. and produces seeds containing hydroxy fatty acids similar to those in castor beans. Research has indicated that lesquerella has potential as a crop plant for Arizona. An important step in the commercialization of this plant for Arizona farms is the development of an efficient agronomic production system. Research to determine the effect of nitrogen (N) rates and timing of N applications on lesquerella production was conducted at the Maricopa Agricultural Center in the 1993 -94 and 1995 -96 seasons. Nitrogen application rates of 0 to 108 and 0 to 162 lbs. N /acre were evaluated in 1993 -94 and 1995 -96 tests, respectively. Seed yields as high as 1780 lbs. /acre were obtained in the 1995 -96 test using a conventional combine for harvest. In both tests, lesquerella biomass production and seed yields increased as the N rate was increased. In 1995 -96, a split application of N in March and April resulted in higher seed yields than a single application in March. Seed oil content decreased in both tests as the N rate was increased. In 1995 -96, seed oil content decreased 12% as the N rate was increased from 0 to 162 lbs. N /acre. The N application rate had no effect on 1000 -seed weight.
47

National Dry Bean Nursery in Bonita, 1995

Clark, L. J., Carpenter, E. W. 10 1900 (has links)
Results of the 1995 National Cooperative Dry Bean Nursery Trials are reported in this paper. Thirty seven varieties of eight different classes of beans were included in this replicated, small plot trial. Bill-Z, the leading pinto bean variety in the area, was the highest yielding variety in the study with a yield just under 3000 pounds per acre. Fleetwood Navy variety and UI 59 Great Northern variety were the next leading varieties with yields about 50 pounds less than Bill-Z. Chase, a pinto variety recently developed with strong rust tolerance, yielded only 2300 pounds per acre in this study. Yields, seed per pound, aerial biomass, harvest index and maturity class are also reported.
48

Fungicide Evaluations on Beans in Southeastern Arizona, 1994-1995

Clark, L. J., Carpenter, E. W., Call, R. E. 10 1900 (has links)
Fungicidal evaluations were performed on pinto beans in two sites in 1994 and one site in 1995 to determine their effect on bean rust, white mold or common bacterial blight The results were mixed between sites and years, but in 1994 the untreated control yielded less than all of the treatments except one and the Fluazinam 500F 1 lb rate was the highest yielding treatment In 1995, no disease symptoms were observed in the field.
49

Ethylmethanesulfonate mutagenesis in selected Vernonia galamensis variety ethiopica lines.

Hadebe, Sandile Thamsanqa. January 2012 (has links)
The overriding objective of this study was to induce genetic variation in Vernonia (Vernonia galamensis variety ethiopica) using ethylmethanesulfonate (EMS) and select mutants for subsequent selective breeding. Vernonia is an underutilised, potential novel oilseed crop with multiple applications in industry mostly due to the production of naturally epoxidised vernolic acid oil. Commercial cultivation of vernonia is significantly hampered by non-uniform seed maturity, tall plant height, seed shattering and lack of appropriate technologies for mechanical harvesting, seed threshing and cleaning. Mutations of a single or few genes possessing target traits are invaluable in crop improvement programs. Chemical mutagenesis using EMS is an important, affordable and effective method to induce random useful genetic mutations in crop plants. Ethylmethanesulfonate mutagenesis has previously been reported to affect various agronomic traits, induce a wide variety of phenotypic mutations and alter both seed oil content and fatty acid profile on several crops. The objectives of this study were: (i) to determine an optimum EMS treatment combination i.e. exposure duration, temperature and dose that would enable 50-60% germination at minimum days to emergence in selected V. galamensis var. ethiopica lines (Vge-1, Vge-4, Vge-7 and Vge-10), (ii) to induce genetic variation using predetermined optimal treatment conditions and select mutants in V. galamensis variety ethiopica lines (Vge-1 and Vge-4) and (iii) to evaluate oil content and fatty acid compositions among seeds of chloroplast mutants, EMS treated seeds and untreated controls of Vge-1 and Vge-4. Before any mutation is administered in plants, it is important that the optimal mutation dose is determined. The lethal dose 50 (LD50) was the standard used in this study to find optimal treatment conditions. Significant interactions (P<0.001) existed between EMS, line, time and temperature with respect to days to 50% emergence, germination percentage and seedling height. Optimal days to 50% emergence (10-12 days) and germination (50- 58%) was achieved for Vge-1, Vge-7 and Vge-10 when treated with 0.372% EMS at 350C for 1 hour treatment. The optimal treatment combination for Vge-4 was 0.372% EMS at 32.50C for 2hr. The treatment combinations that yielded optimum results in the tested lines were utilized to induce large scale mutations in V. galamensis to select target mutants in the field. Large scale mutation was conducted using the observed optimal treatment conditions. Ethylmethanesulfonate mutagenesis significantly delayed days to head formation, days to flowering and days to maturity on both lines. Delays in days to emergence were only significant in Vge-4. EMS treatment also significantly reduced germination percentage, number of seeds per head, number of fertile plants, plant height and plot yield for both Vge-1 and Vge-4. Thousand seed weight significantly increased in treated seeds of the two lines. Chlorophyll mutants were observed for tested lines associated with high count of sterility for both lines. Ethylmethanesulfonate successfully induced phenotypic mutation in selected vernonia lines, however at this stage the effect of mutation on vernonia seed oil content and fatty acid was unknown. Liquid gas chromatography method was employed for oil and fatty acids analysis. In Vge-1, significant differences were observed in composition of linoleic and oleic acid due to the mutagenesis. Significant increases in linoleic and oleic acid composition were found in chloroplast mutants due to EMS mutagenesis. No significant differences were detected in fatty acid compositions in Vge-4 after the EMS treatment. Differential responses were observed when lines were compared at various EMS mutation levels showing significant effect on vernolic, linoleic and oleic acids compositions. In both lines no differences were detected on seed oil content, palmitic acid, steraic acid and arachidic acid compositions after the treatment. Oil content significantly and positively correlated with vernolic acid for Vge-1 (P<0.001; r= 0.898) and Vge-4 (P<0.05; r= 0.65). Vernolic acid significantly and negatively correlated with other fatty acids. The study found that EMS mutagenesis significantly changed the oleic acid and linoleic acid compositions in vernonia. However, the oil content and vernolic acid composition were not significantly affected by EMS treatment. This study established that EMS was successful in inducing genetic variation (in agronomic traits, seed oil content and fatty acid composition) in the two tested lines of V. galamensis. Data from a single planting generation is insufficient to conclude fully on the effect of EMS on V. galamensis; therefore it is highly recommended that further multigenerational studies should be conducted with an increased number of testing lines from a wide range of environmental backgrounds. / Thesis (M.Sc.Agric.)-University of KwaZulu-Natal, Pietermaritzburg, 2012.
50

Modelling the production of biodiesel from non-edible oils (Jatropha curcas oil and Tobacco seed oil (TSO): a kinetic study

Mthembu, Feziwe Celile January 2017 (has links)
Thesis submitted in partial fulfilment of the requirements for the degree of Master of Science in Engineering at the School of Chemical and Metallurgical Engineering, Faculty of Engineering and the Built Environment, University of the Witwatersrand Johannesburg, South Africa October, 2017 / The significant increase in the primary energy demand and the effort to reduce harmful emissions related to the greenhouse gases enhanced the search for alternative energy. Production and modelling processes of biofuel from non-edible oil sources assist in the process development of an environmentally friendly fuel such as biodiesel. This work focused on the kinetic modelling of biodiesel synthesised from non-edible oils. Two types of non-edible oils (Jatropha curcas seed oil and Tobacco seed oil) were used in this study including the development of the kinetic behaviour of the transesterification reaction. A linear polynomial model was generated from experimental data found in literature in order to study the influence of operating parameters during biodiesel production. It was found that the temperature improves the yield of biodiesel; this is attributed to the fact that temperature affects the reaction rate constants; and the higher the reaction rate, the lower the activation energy required for a reaction to occur. The optimum conditions for the transesterification of Jatropha curcas seed oil are a temperature of 55 0C, methanol to oil ratio of 6:1, catalyst concentration of 1.2% KOH (by volume of oil), and agitation speed range of 0-250 rpm. Results from both the homogeneous and heterogeneous reactions of Jatropha curcas oil and tobacco seed oil were used to verify the theoretical kinetic and empirical models. It was found that both models describe the kinetic behaviour of transesterification with minor deviations in the estimated parameters. However, the use of empirical model in determining the reaction order, as opposed to the theoretical assumption, gave a second order with respect to oil triglycerides at a temperature of 60 0C. The theoretical kinetic model gave a first order with respect to oil triglycerides. In this case, the activation energy was found to be 71.83 kJ/mol and pre-exponential factor was found to be 2.48 x1010. More investigation should be done to describe the kinetic behaviour of biodiesel production from non-edible oil in order to confirm the correct reaction order and why there is change in reaction order when the temperature increases above 60°C. / MT2018

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