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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.
91

Selection of salt tolerant embryogenic line in Jatropha curcas L., which has potentiality of biodiesel / Chọn lọc dòng mô phôi soma chịu mặn của cây cọc rào (Jatropha curcas L.), một loài cây có tiềm năng về nhiên liệu sinh học

Do, Dang Giap, Tran, Dieu Thai, Tran, Trong Tuan, Nguyen, Thi Huyen Trang, Nguyen, Thi Kim Phuc, Duong, Duc Hieu 24 August 2017 (has links) (PDF)
The embryogenic calli were grown on MS medium containing NaCl with concentrations from 50 to 300 mM. After 2 weeks of culture, salinity tolerance threshold was identified at 150 mM NaCl. Higher concentrations of NaCl stimulated a significant reduction in the calli survival rate and the highest rate was 78.67% at 50 mM. After subculturing callus to the embryo culture medium containing NaCl, the growth and embryogenesis were not affected at the concentrations of 50 – 100 mM. Especially, at 50 mM NaCl the embryogenesis rate reached 83.33%. In contrast, 150 mM NaCl inhibited the somatic embryogenesis. After 4 weeks, culturing somatic embryos on medium MS with addition of 0.07 mg/l spermidin at 50 – 100 mM NaCl, the embryogenesis was considered good and embryos developed through several stages: globular, heart, torpedo and cotyledonary. However, at 150 mM NaCl the globular stage appeared in the culture process. The process of morphohistology and using dye carmine – iod and acridine orange observed the structure of generative callus and embryos at several stages. / Mô sẹo có khả năng phát sinh phôi được nuôi cấy trong môi trường có chứa muối NaCl với nồng độ thay đổi từ 50 – 300 mM. Sau 2 tuần nuôi cấy, chúng tôi xác định được ngưỡng chịu mặn của mô sẹo có khả năng sinh phôi cây Cọc rào là 150 mM. Nồng độ muối NaCl càng cao thì tỷ lệ sống của mô sẹo giảm dần và đạt giá trị cao nhất là 78,67% tại nồng độ 50 mM NaCl. Khi chuyển mô sẹo sang môi trường phát sinh phôi có chứa muối NaCl với nồng độ thay đổi, chúng tôi thấy ở nồng độ muối NaCl 50 – 100 mM không ảnh hưởng đến khả năng sinh trưởng và phát sinh phôi, đặc biệt là tại nồng độ 50 mM NaCl giúp kích thích sự hình thành phôi từ mô sẹo với tỷ lệ hình thành phôi đạt 83,33%. Ngược lại, nồng độ từ 150 mM NaCl gây ức chế quá trình hình thành phôi soma từ mô sẹo. Tiếp tục khảo sát ảnh hưởng của muối đến khả năng phát triển và nảy mầm của phôi soma. Ghi nhận kết quả sau 4 tuần nuôi cấy phôi soma trong môi trường MS có bổ sung 0.07 mg/l spermidin, tại nồng độ 50 – 100 mM NaCl khả năng hình thành phôi tốt và phôi phát triển qua các giai đoạn phôi hình cầu, hình tim, hình thủy lôi và hình lá mầm. Đặc biệt ở nồng độ 50 mM số lượng phôi lá mầm đạt giá trị cao với 13,33 phôi. Nồng độ muối NaCl 150 mM chỉ xuất hiện phôi hình cầu trong suốt thời gian nuôi cấy. Quá trình giải phẫu hình thái phôi và sử dụng thuốc nhuộm 2 màu carmin – iod và acridine orange đã cho thấy rõ hơn về cấu trúc mô sẹo có khả năng sinh phôi và phôi hình thái.
92

[en] PARAMETRIC SENSITIVITY ANALYSIS CONSIDERING THE LIFE CYCLE OF BASE OILS FOR THE PRODUCTION OF MINERAL AND VEGETABLE LUBRICANTS / [pt] ANÁLISE DE SENSIBILIDADE PARAMÉTRICA NO CICLO DE VIDA DE ÓLEOS BASE PARA PRODUÇÃO DE LUBRIFICANTES MINERAIS E VEGETAIS

PEDRO EMILIO GALLARDO SANDOVAL 12 September 2017 (has links)
[pt] A constante procura por desenvolvimento sustentável tem originado a criação de novas técnicas de avaliação dos custos ambientais nos sistemas de produção. Atualmente a produção de óleos lubrificantes está sendo ambientalmente avaliada devido aos grandes impactos ambientais gerados pela produção, utilização e disposição final dos óleos de base mineral. Como alternativa para os óleos de bases minerais vem-se estudando a substituição por óleos oriundos de bases animais e vegetais, os quais apresentam melhores características ambientais. Este trabalho teve por objetivo realizar uma análise de ciclo de vida simplificada (berço-porta) das fases de produção de 1 kg de óleo de base mineral e 1 kg de óleo de base de óleo de jatropha com a utilização de uma análise de sensibilidade. A comparação para a obtenção dos dados foi realizada nos mesmos cenários de produção tanto para os óleos lubrificantes de base de jatropha quanto para os óleos lubrificantes de base mineral. Os resultados nestes cenários indicaram que na produção do óleo de jatropha, o potencial de aquecimento global foi 1,01 kg maior do que o cenário base da produção do óleo mineral; o potencial de eutrofização de água foi 2,06E-04 kg maior do que o cenário base da produção do óleo mineral; o potencial de toxicidade humana foi 0,08 kg maior do que o cenário base da produção do óleo mineral e o potencial de depleção de água foi 1,33E-01 kg maior do que o cenário base da produção do óleo mineral. No cenário base da produção do óleo mineral, o potencial de depleção de combustíveis fósseis foi 0,70 kg maior do que o cenário base da produção do óleo de jatropha. Entretanto, no contexto desta modelagem deve-se ainda levar em consideração outros parâmetros, como os relacionados às limitações geográficas, pois algumas discrepâncias nas análises do ciclo de vida dos óleos podem ocorrer. / [en] The continuously effort to reach the sustainable development has led to the creation of new techniques for assess environmental costs of the production systems. Nowadays the production of mineral oil base lubricants is assessed due to the large environmental impacts generated in their production, use and final disposal. As alternatives to the substitution of mineral oil base lubricants, vegetable oil base lubricants have been studied and used because their environmental characteristics. Hence, this study focused on execute a simplified LCA (cradle-to-gate analysis) for the production phase of 1 kg of mineral base oil and 1 kg of jatropha base oil trough a sensitivity analysis. The comparison for both oil bases was performed under the same production scenarios. Results shown that the jatropha base oil production scenario presented 1,01 kg more than the base mineral oil production scenario; the fresh water eutrophication potential had 2,06E-04 kg more than the base mineral oil scenario; the human toxicity potential presented 0,08 kg more than the base mineral oil scenario; the water depletion potential showed 1,33E-01 kg more than the base mineral oil scenario. On the mineral base oil production scenario, the fossil depletion potential shown 0,70 kg more than the base jatropha oil production scenario. However, it had to still take in consideration parameters such as geographic limitations, due to some discrepancies in the life cycle assessment of oils can occur.
93

Sustainable design of oilseed-based biofuel supply chains : the case of Jatropha in Burkina Faso / Conception de filières durables de production de biocarburants oléagineux : le cas des filières Jatropha au Burkina Faso

Chapuis, Arnaud 28 March 2014 (has links)
Au Burkina Faso, les biocarburants suscitent de nombreux espoirs quant au développement de l'accès à l'énergie en zone rurale et à la substitution des carburants fossiles importés. Plusieurs initiatives de production de biocarburants à partir de Jatropha ont été lancées au cours des dernières années par des ONG et des opérateurs privés. Le gouvernement envisage de définir une politique d’accompagnement pour le développement de ce secteur. Les bénéfices potentiels issus de cette activité, en terme de contribution au développement durable, doivent donc être soigneusement étudiés afin de prendre les décisions adéquates. L’objectif de ce travail est d’évaluer les opportunités de développement des biocarburants, en définissant les possibilités techniques dans le contexte et en analysant à quelles conditions et dans quelle mesure elles peuvent contribuer au développement durable. L'approche repose sur la modélisation des procédés impliqués dans la production, couplée à des outils d'évaluation environnementale et économique. L'efficacité économique est évaluée par une analyse de la valeur ajoutée produite au sein des filières, ainsi que sa distribution sous forme de revenus, aux employés, aux agents de la filière, à l'état et aux banques. Les impacts environnementaux, notamment les émissions de GES et la consommation d'énergie fossile, sont évalués à l'aide d'une analyse de cycle de vie. Trois produits finaux différents ont été envisagés : l'huile végétale brute (HVB) ou raffinée, destinée à des applications stationnaires et le biodiesel dédié aux transports. Une analyse individuelle de chaque procédé a permis d'identifier les paramètres les plus sensibles au niveau local. Pour tous les procédés, le prix de la matière première conditionne largement le coût de production. Pour la production d’HVB, le rendement en huile et la teneur en huile des graines ont une importance capitale. Les performances économiques du raffinage et de la transestérification de l’huile sont largement influencées par la capacité de transformation des procédés en raison d’économies d'échelle, et dans une moindre mesure, par la technologie et les ressources utilisées pour la fourniture énergétique. Dans le cas de la production de biodiesel, le prix du méthanol est également un facteur crucial. La méthode d'évaluation développée a été appliquée à plusieurs scénarios de production de biocarburants à partir de graines de Jatropha produites par les petits exploitants. Les résultats montrent que la méthode permet d’apporter des informations essentielles pour la prise de décisions politiques. Sur la base d'un prix de marché des graines de 100 FCFA/kg, les trois types de biocarburants envisagés peuvent être produits de manière rentable. Dans certains cas, l’utilisation de technologies avancées pour l'approvisionnement en énergie et la valorisation des sous-produits est indispensable pour atteindre un coût de production compétitif. Cela pourrait aussi être une solution pour augmenter le prix des graines afin d’assurer des revenus plus élevés aux agriculteurs. La production d'huile raffinée pour la production d’électricité est particulièrement coûteuse et nécessite une production à grande échelle pour être rentable. Les filières impliquant une usine de biodiesel approvisionnées par plusieurs huileries décentralisées constituent une solution pour contribuer à la fois à l’amélioration de l'accès à l'énergie en zone rurale et à la substitution des combustibles fossiles. Les revenus perçus par l'Etat sont directement liés à la valeur ajoutée et aux bénéfices générés par les producteurs de biocarburants. Enfin, les impacts environnementaux de la production d’huile sont relativement faibles, en termes d'émissions de GES et de consommation d'énergie fossile, en particulier si la fourniture énergétique est basée sur une ressource renouvelable. En revanche, les impacts de la production de biodiesel sont largement affectés par l'utilisation de méthanol. / The development of biofuel production in Burkina Faso, raises high expectations regarding the development of rural energy access and the substitution of imported fossil fuels. Several initiatives for biofuel production from Jatropha oilseeds were launched in recent year by NGOs and private operators.The government is planning to define a policy framework to support the development of this sector. To this end, the potential benefits from this activity needs to be carefully investigated in regard to sustainable development objectives.The goal of this work was to investigate these opportunities by determining the technical possibilities regarding the context and in what conditions and to what extent they can contribute to sustainable development objectives. The approach was based on the modelling and simulation of production processes coupled with environmental and economic assessment tools. Specific experiments were also led whenever data were not available, as for the determination of the oil yield of a screw press. Economic efficiency was assessed using value chain analysis, which consists in calculating the value added generated by the different activities involved in a supply chain, and the distribution of this value in the form of income to the employees, the supply chain players, the state and the banking institutions. Environmental impacts, including greenhouse gas emissions and fossil energy consumption, are evaluated using a partial life-cycle assessment. The production of three different final products was investigated, i.e. straight vegetable oil (SVO), refined oil aimed to be used for stationary applications (power generation, shaft power, pumping…) and biodiesel dedicated to transportation. The analysis of individual processes allowed to identify the most sensitive parameters at a local level. As a general trend for all processes, the price of feedstock dramatically affects the production cost. For SVO production, the oil recovery and the seeds oil content are of paramount importance. The economic performances of the refining and transesterification processes are largely conditioned by the processing capacity, due to economies of scale, and to a lesser extent by the solution employed for energy supply. In the case of biodiesel production, the price of methanol is also a crucial factor. The developed assessment method was applied to several prospective biofuel supply chains, all relying on the production of Jatropha seeds by smallholders. The results have shown that the method can bring crucial information to policy makers. Based on a seed market price of 100 FCFA/kg, any type of biofuel can be produced in a cost effective way. In some cases, the implementation of advanced technologies for energy supply and by-product valorisation is needed to reach the required production cost. This could also be a solution to increase the price of seeds so as to provide higher incomes to farmers. The production of refined oil for power generation appears to be rather expensive relatively to the target, which imposes large processing scales. Supply chains involving a biodiesel plant supplied by several decentralised SVO plants constitute a solution for addressing at the same time rural energy access and the substitution of fossil fuels. Then the income perceived by the State is directly determined by the value and the profits generated by biofuel producers. Eventually, the environmental impacts related to seed processing, in terms of GHG emissions and fossil energy consumption, is relatively low especially when energy requirements are supplied from a renewable resource. By contrast, the impacts of biodiesel production are systematically impaired by the use of methanol of fossil origin in the process.
94

Selection of salt tolerant embryogenic line in Jatropha curcas L., which has potentiality of biodiesel: Research article

Do, Dang Giap, Tran, Dieu Thai, Tran, Trong Tuan, Nguyen, Thi Huyen Trang, Nguyen, Thi Kim Phuc, Duong, Duc Hieu 24 August 2017 (has links)
The embryogenic calli were grown on MS medium containing NaCl with concentrations from 50 to 300 mM. After 2 weeks of culture, salinity tolerance threshold was identified at 150 mM NaCl. Higher concentrations of NaCl stimulated a significant reduction in the calli survival rate and the highest rate was 78.67% at 50 mM. After subculturing callus to the embryo culture medium containing NaCl, the growth and embryogenesis were not affected at the concentrations of 50 – 100 mM. Especially, at 50 mM NaCl the embryogenesis rate reached 83.33%. In contrast, 150 mM NaCl inhibited the somatic embryogenesis. After 4 weeks, culturing somatic embryos on medium MS with addition of 0.07 mg/l spermidin at 50 – 100 mM NaCl, the embryogenesis was considered good and embryos developed through several stages: globular, heart, torpedo and cotyledonary. However, at 150 mM NaCl the globular stage appeared in the culture process. The process of morphohistology and using dye carmine – iod and acridine orange observed the structure of generative callus and embryos at several stages. / Mô sẹo có khả năng phát sinh phôi được nuôi cấy trong môi trường có chứa muối NaCl với nồng độ thay đổi từ 50 – 300 mM. Sau 2 tuần nuôi cấy, chúng tôi xác định được ngưỡng chịu mặn của mô sẹo có khả năng sinh phôi cây Cọc rào là 150 mM. Nồng độ muối NaCl càng cao thì tỷ lệ sống của mô sẹo giảm dần và đạt giá trị cao nhất là 78,67% tại nồng độ 50 mM NaCl. Khi chuyển mô sẹo sang môi trường phát sinh phôi có chứa muối NaCl với nồng độ thay đổi, chúng tôi thấy ở nồng độ muối NaCl 50 – 100 mM không ảnh hưởng đến khả năng sinh trưởng và phát sinh phôi, đặc biệt là tại nồng độ 50 mM NaCl giúp kích thích sự hình thành phôi từ mô sẹo với tỷ lệ hình thành phôi đạt 83,33%. Ngược lại, nồng độ từ 150 mM NaCl gây ức chế quá trình hình thành phôi soma từ mô sẹo. Tiếp tục khảo sát ảnh hưởng của muối đến khả năng phát triển và nảy mầm của phôi soma. Ghi nhận kết quả sau 4 tuần nuôi cấy phôi soma trong môi trường MS có bổ sung 0.07 mg/l spermidin, tại nồng độ 50 – 100 mM NaCl khả năng hình thành phôi tốt và phôi phát triển qua các giai đoạn phôi hình cầu, hình tim, hình thủy lôi và hình lá mầm. Đặc biệt ở nồng độ 50 mM số lượng phôi lá mầm đạt giá trị cao với 13,33 phôi. Nồng độ muối NaCl 150 mM chỉ xuất hiện phôi hình cầu trong suốt thời gian nuôi cấy. Quá trình giải phẫu hình thái phôi và sử dụng thuốc nhuộm 2 màu carmin – iod và acridine orange đã cho thấy rõ hơn về cấu trúc mô sẹo có khả năng sinh phôi và phôi hình thái.
95

Economic development in the Southern African Development Community region : is Rainbow Biotech the next big thing?

Roux, Pieter G. Van Der Byl 03 1900 (has links)
Thesis (MBA)--Stellenbosch University, 2011. / The purpose of the study is to investigate the feasibility and sustainability of producing biodiesel from Jatropha, which contains oil in its seeds by using the Rainbow Biotech economic intervention or also known as the Distributed Food and Fuel Plantation (DFFP) model. The DFFP model is an effective mechanism for producing food and fuel in conjunction with each other, without the biodiesel production influencing the production of food in an adverse way. This is very important, as food security is a high priority for Africa, in order to address the problem of hunger and poverty. Biodiesel produced from Jatropha is an eco-friendly and sustainable alternative to fossil fuel diesel, as it is a carbon neutral fuel. Jatropha cultivation will also create much needed employment in the rural areas of Africa, which has the highest need for socio-economic development on the continent. Jatropha also has the ability to grow on marginal soils and wastelands. Africa has vast open spaces on which Jatropha, as a biodiesel source, can be cultivated without infringing on food production areas. The energy return of the whole production cycle of Jatropha biodiesel is nevertheless a source of much debate. Most stakeholders felt that the energy return is negative. No agreement has yet been reached about whether the energy content of the by-products from biodiesel must be included in the integrated energy balance equation. In order to make biodiesel from Jatropha a sustainable alternative for small farmers in the Southern African Development Community (SADC), government and regional policies will have to support it by promoting it actively. This will generate interest from global biodiesel investors who will then be willing to invest in projects based on the DFFP model of economic development. The DFFP model offers investors economic returns on investment of between 29 and 33 per cent and payback periods of less than four years. It is a very attractive economic development instrument, as it will ensure equitable and sustainable economic and rural expansion in SADC. Ultimately, this model has the potential to create a better life for all the inhabitants on the African continent. Rainbow Biotech (the DFFP model), as an economic development mechanism, will therefore indeed be the next big thing for the SADC in the future.
96

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
97

Crop evapotranspiration and crop coefficient of jatropha from first to fourth year / Evapotranspiração e coeficiente de cultivo do pinhão-manso do primeiro ao quarto ano

Lena, Bruno Patias 10 November 2016 (has links)
The determination of crop coefficient (Kc) with adequate methodology is important to quantify regional water requirement. Jatropha (Jatropha curcas L.) Kc is still unknown and this information will be essential to provide reliable irrigation parameters, as well as for crop zoning. The objective of this study was to determine jatropha actual crop evapotranspiration (ETc) and Kc from 1st to 4th growing year, and correlate Kc with leaf area index (LAI) and cumulative thermal unit (CTU). The experiment was performed from March 2012 to August 2015 at \"Luiz de Queiroz\" College of Agriculture (ESALQ)/University of São Paulo (USP), at Piracicaba city, SP, Brazil. The experiment was divided into center pivot, drip, and rainfed treatments. Two large weighing lysimeters (12 m2 each lysimeter) per treatment were used to determine jatropha ETc (one plant per lysimeter). Reference evapotranspiration (ET0) was determined by Penman-Monteith method from a weather station data situated close to the treatments. Daily Kc was determined for the two irrigated treatments by the ration between ETc and ET0 (Kc=ETc/ET0). LAI was determined using the LAI-2200 plant canopy analyzer, which was previously calibrated for jatropha canopy type. In all growing years, LAI was almost zero at the beginning of vegetative stage, increasing until a maximum during productive stage, and decreasing to zero in the leaf senescence stage. Annual ETc trend during the three growing was very similar, which was explained by the different growing periods and the LAI variation. In the 1st year Kc was 0.47 for both treatments. In the 2nd, 3rd, and 4th years Kc ranged from 0.15 to 1.38 for center pivot treatment and from 0.15 to 1.25 for drip treatment. Kc average in 2nd, 3rd, and 4th years during vegetative and productive growing periods was 0.77, 0.93, and 0.82 for center pivot treatment, respectively, and 0.69, 0.79, and 0.74 for drip treatment, respectively. The relationship between Kc and LAI for the center pivot treatment was adjusted to a logarithmical equation with coefficient of determination (R2) and root mean square error (RMSE) of 0.7643 and 0.334, respectively. For the drip treatment R2 was 0.8443 and 0.2079, respectively. In all three years analyzed, Kc related to CTU by a 3rd degree polynomial equation for both treatments. / A determinação de coeficiente de cultivo (Kc) com metodologia adequada é essencial para quantificar o consumo hídrico de cultivos em diferentes regiões. Valores de Kc do pinhão-manso (Jatropha curcas L.) ainda não foram determinados e essa informação é muito importante para auxiliar o manejo de irrigação de maneira adequada. O objetivo desse estudo foi determinar a evapotranspiração (ETc) e Kc do 1º ao 4º ano de cultivo do pinhão-manso, e correlacionar Kc com o índice de área foliar (IAF) e a soma da unidade térmica (SUT). O experimento foi realizado de março de 2012 à agosto de 2015 na Escola Superior de Agricultura \"Luiz de Queiroz\" (ESALQ)/Universidade de São Paulo (USP), na cidade de Piracicaba, SP, Brasil. O experimento foi divido nos tratamentos irrigados por pivô central, gotejamento e sem irrigação. Foram utilizados dois lisímetros de pesagem (12 m2 de superfície em cada lisímetro) por tratamento para realizar a determinação de ETc (uma planta por lisímetros). A evapotranspiração de referência (ET0) foi determinado pelo método de Penman-Monteith a partir de dados meteorológicos coletados na estação meteorológica localizada ao lado do experimento. Valores diários de Kc foram determinados nos tratamentos irrigados pela razão entre ETc e ET0 (Kc=ETc/ET0). IAF foi determinado utilizando o equipamento LAI-2200 Plant Canopy Analyzer, que foi previamente calibrado para adequar as características do dossel do pinhão-manso. Em todos os anos avaliados, o IAF foi quase zero durante o início do período vegetativo, aumentando os valores conforme a planta começou a se desenvolver até atingir valores máximos durante o período produtivo, decrescendo os valores até zero no estádio de desenvolvimento de senescência foliar. A variação anual de ETc no 2º, 3º e 4º ano foi muito similar, explicado pelos diferentes períodos de desenvolvimento da cultura e a variação de IAF no ano. No 1º ano, Kc foi 0,47 para os dois tratamentos irrigados. No 2º, 3º e 4º ano, Kc variou de 0,15 a 1,38 no tratamento irrigado por pivô central e de 0,15 a 1,15 no tratamento irrigado por gotejamento. A média dos valores de Kc no 2º, 3º e 4º ano durante os períodos vegetativos e produtivos foi de 0,77, 0,93 e 0,82 no tratamento irrigado por pivô central, respectivamente, e 0,69, 0,79 e 0,74 no tratamento irrigado por gotejamento, respectivamente. A relação entre Kc e IAF mostrou, para o tratamento irrigado por pivô central, um ajuste logaritmo com coeficiente de determinação (R2) e somatória do erro médio ao quadrado (SEMQ) de 0,7643 e 0,334, respectivamente, e 0,8443 e 0,2079 para o tratamento irrigado por gotejamento, respectivamente. Nos três anos analisados, Kc correlacionado com SUT mostrou o melhor ajuste à equação polinomial de 2ª ordem para os dois tratamentos.
98

Síntese enzimática do biodiesel de Jatropha curcas pela rota etílica / Enzymatic synthesis of Jatropha curcas biodiesel by ethylic route

Souza, Lívia Tereza de Andrade 01 October 2010 (has links)
O esperado crescimento na demanda de biodiesel no mercado mundial tem impulsionado uma evolução constante em seu sistema de produção de forma a torná-lo mais eficiente e ambientalmente favorável. O presente trabalho teve como objetivo verificar o potencial do óleo de pinhão manso para obtenção de biodiesel pela via enzimática empregando etanol com agente acilante. Para alcançar o objetivo proposto, as atividades experimentais foram iniciadas pela adequação do óleo de pinhão manso bruto para sua utilização como matériaprima na reação de transesterificação, incluindo as etapas de degomagem, neutralização e secagem. O óleo tratado, após caracterização físico-química, foi utilizado nos testes de triagem do biocatalisador enzimático testando diferentes preparações de lipases (EC 3.1.1.3) tanto na forma livre como imobilizada em SiO2-PVA, para mediar à síntese de biodiesel em meio isento de solventes. Os testes indicaram que as lipases na forma imobilizada foram mais eficientes e permitiram selecionar os derivados imobilizados das lipases de Burkholderia cepacia e Pseudomonas fluorescens como as preparações mais adequadas para catalisar a síntese de biodiesel a partir do óleo de pinhão, com rendimentos reacionais de 93,18% e 85,67%, respectivamente. Na segunda etapa do trabalho, os derivados imobilizados selecionados foram testados na reação de interesse, mantendo-se fixa as condições reacionais (temperatura 45oC, 1:9 de razão molar óleo/etanol e 500 unidades de atividade lipolítica por grama de óleo), empregando reatores de vidro acoplados com condensador de refluxo, para evitar perda de etanol. O monitoramento da reação foi efetuado pela determinação dos ésteres etílicos formados (Cromatografia de fase gasosa) e viscosidade cinemática em amostras retiradas ao longo da reação. O produto transesterificado (biodiesel) foi purificado e submetido às análises para caracterização de suas propriedades físico-químicas, incluindo estudo reológico, espectroscopia de absorção na região do infravermelho (FTIR), análise termogravimétrica (TG) e ressonância magnética nuclear protônica (1H-RMN). Os resultados obtidos permitiram confirmar que a lipase de Burkholderia cepacia foi a preparação de lipase mais eficiente para mediar à síntese do biodiesel do óleo de pinhão manso, alcançando rendimento de transesterificação superior a 97% (72h). O biodiesel produzido manteve-se estável termicamente até 128oC e não sendo constatada contaminação do produto com glicerol ou água residual, assegurando a eficiência da etapa de purificação do produto transesterificado. Experimentos adicionais foram ainda efetuados sob irradiação de micro-ondas e os resultados obtidos indicaram que o aquecimento por micro-ondas constitui um procedimento potencial para a produção de biodiesel, tendo em vista a considerável redução do tempo global de reação. A estabilidade operacional da lipase imobilizada foi determinada em bateladas consecutivas sob aquecimento convencional e irradiação de micro-ondas, revelando um tempo de meia-vida do biocatalisador de 110 e 26,5h, respectivamente. A real contribuição da aceleração da reação por meio de irradiação de micro-ondas deverá ser reavaliada levando em consideração a acentuada perda da atividade sintética do biocatalisador. / The expected increase in the biodiesel demand worldwide has brought a constant evolution in its production system in order to make it more efficient and environmentally favorable. The objective of present work was to verify the potential of Jatropha oil as raw material to produce biodiesel by enzymatic route using ethanol as acilant agent. To attain the proposed objective, the experimental activities were starting by treating the oil to attain suitable properties to be used in the transesterification reaction, including the degumming, neutralization and drying steps. The treated oil, after physico-chemical characterization was used to carry out a screening test to select the most suitable biocatalyst by means of testing different preparations of lipases (EC 3.1.1.3) in free form as well as immobilized in SiO2-PVA, to mediate the biodiesel synthesis in solvent free system. The assays indicated that the immobilized lipases were more efficient than free ones and allowed selecting the immobilized derivatives from Burkholderia cepacia and Pseudomonas fluorescens as the most suitable preparations to catalyze biodiesel synthesis from Jatropha oil, attaining yields of 93.18% and 85.67%, respectively. In the second step, the selected immobilized derivatives were used to catalyze the reaction of interest maintaining the previous set conditions (temperature 45oC, 1:9 molar ratio oil/ethanol and 500 units of lipolytic activity per gram of oil) using a glass reactor coupled with condenser to avoid ethanol loss. The reaction was monitored by determining the formed ethyl esters by gas chromatography and viscosity in samples taken from the reactor during the reaction. The transesterified product (biodiesel) was purified and submitted to further analyses for physico-chemical properties, including rheological study, FTIR, TG and 1H NMR. The obtained results confirmed that the lipase from Burkholderia cepacia was the most efficient biocatalyst to mediate the biodiesel synthesis from Jatropha oil, attaining transesterification yields higher than 97% (72h. The product biodiesel was thermo stable up to 128oC and no residual glycerol or water contaminations were detected, assuring the efficiency of the down stream process. Additional experiments were performed under microwave irradiation and the results suggested that the microwave heating constitutes a potential procedure to enhance the reaction rate by reducing the global reaction time. The operational stability of the immobilized lipase was determined in repeated batch runs under conventional and microwave heating systems, revealing biocatalyst half-life time of 110 and 26.5 h, respectively. Therefore, the real contribution of the microwave irradiations to enhance the reaction should be revalued by taking into account the lost of the biocatalyst activity.
99

Isolamento e quantificação de flavonóides e abordagem das atividades antioxidante e antimicrobiana de Jatropha gossypiifolia L.

VEIGA, Andrex Augusto Silva da 30 December 2008 (has links)
Submitted by Irvana Coutinho (irvana@ufpa.br) on 2011-05-03T12:26:17Z No. of bitstreams: 2 VEIGA, WagnerAndrex_PPGCFarm.pdf: 899908 bytes, checksum: 8b1f0d93ec4c735007961fbef3ae5ce5 (MD5) license_rdf: 22876 bytes, checksum: 0a4e855daae7a181424315bc63e71991 (MD5) / Made available in DSpace on 2011-05-03T12:26:17Z (GMT). No. of bitstreams: 2 VEIGA, WagnerAndrex_PPGCFarm.pdf: 899908 bytes, checksum: 8b1f0d93ec4c735007961fbef3ae5ce5 (MD5) license_rdf: 22876 bytes, checksum: 0a4e855daae7a181424315bc63e71991 (MD5) Previous issue date: 2008 / Jatropha gossypiifolia L. (Euphorbiaceae), conhecida no Pará como pião-roxo, é utilizada no tratamento de hemorróidas, queimaduras, dores estomacais, entre outras doenças. Diante da importância do vegetal na região torna-se necessária a sua investigação visando contribuir para o seu aproveitamento no desenvolvimento de fitoterápicos. Para tanto, buscou-se determinar o perfil cromatográfico do extrato etanólico bruto (EEB), por cromatografia de camada delgada (CCD) e por cromatografia líquida de alta eficiência (CLAE), o teor de flavonóides totais e dos flavonóides isolados no extrato. Foram realizados também ensaios de atividade antimicrobiana com o EEB e as frações obtidas a partir dele (frações hexânica, clorofórmica, acetato de etila e residual). A atividade antioxidante do extrato e suas frações também foi caracterizada. O material vegetal foi coletado no horto de plantas medicinais da EMBRAPA – Amazônia oriental e com ele preparou-se, por percolação, o EEB; utilizando um evaporador rotativo a baixa pressão, obteve-se o extrato seco que, posteriormente, foi fracionado por partição líquido-líquido sucessivamente com hexano, clorofórmio e acetato de etila. As frações obtidas foram também concentradas a baixa pressão. A fração acetato de etila foi novamente fracionada fornecendo uma fração acetona (FAct-II), uma nova acetato de etila (FA-II), metanólica (FM-II) e resíduo sólido (RS-II). FAct-II foi submetida a cromatografia líquida a média pressão obtendo-se as subfrações Fr SAc1-II e Fr SAc3-II denominadas de Jg1 e Jg2, respectivamente. A prospecção química no extrato e nas frações dos metabólitos foi realizada em triplicata, sendo evidenciada a presença dos seguintes polifenóis: taninos catéquicos e flavonóides. A análise por CCD foi realizada utilizando-se o eluente acetato de etila/ácido fórmico/ácido acético glacial/água (100:11:11:26), sobre gel de sílica de fase normal, sendo observadas zonas com fator de retenção 0,65, 0,72 e 0,77, reativas à solução de FeCl3. O cromatograma por CLAE do EEB apresentou três picos significativos (valores médios de tr: 13,24 min, 15,02 min e 16,00 min) cujos espectros são característicos de flavonóides. No calculo do teor de flavonóides, aplicando-se a média das leituras de absorvância (A: 0,874), chegou-se ao teor de 2,04%. A concentração encontrada para cada substância isolada foi de 340 μg para Jg1 e 406 μg para Jg2 por mililitro da solução de extrato. Quanto às atividades biológicas testadas, FA-I e FR-I inibiram o crescimento de S. aureus e C. albicans como também apresentaram maior potencial antioxidante. Os resultados fornecem parâmetros acerca de polifenóis adequados para o controle de qualidade como marcadores químicos, e teor de destes possíveis marcadores. / Jatropha gossypiifolia L (Euphobeaceae), known in Pará as “Pião roxo” is used for treatment of hemorroids, burns, stomach pains among other diseases, the importance of this plant to this region has led to its research in order to improve its phytotherapeutic development. During the analysis, the chromatographic profiles of its Crude Ethanolic Extract (CEE)was determined using Thin Layer chromatography (TLC) and High Performance Liquid Chromatography (HPLC) methods. The total and isolated flavonoids quantities were determined. Antimicrobial activity essays of the crude ethanolic extract were also conducted and the fractions obtained (hexanic, chloroform, ethyl acetate and residual fractions). The antioxidant activities of the extract and the fractions were also characterized. The plant materials were collected from EMBRAPA medicinal plants garden in the east Amazon and then extracted through percolation to obtain crude ethanolic extract. The dry extract was obtained using low pressure rotative evaporator followed by liquid-liquid partition with hexane, chloroform and ethyl acetate successively. The fractions obtained were also concentrated at low pressure, The ethyl acetate fractions were re-fractioned, giving rise to acetone fraction (ActF-II), a new ethyl acetate (AF-II), methanolic fraction (MF-II) and a solid residue (SR-II). ActF-II was submitted to liquid chromatography at average pressure, resulting in sub-fractions like Fr ActS-II and Fr ActS3-II called Jg1 and Jg2, respectively. Chemical prospection of the Extract and the metabolite fractions were conducted in triplicates, leading to the observation of the presence of the following polyphenols: Catechines, Tannins and flavonoids. The analysis by thin Layer Chromatography (TLC) was conducted using eluent of ethyl acetate/formic acid/glacial acetic acid/water at (100:11:11:26) on a normal phase silica gel, showing the retention factors in the following zones:0.65, 0.72, and 0.77 in reaction to Fecl3 solution . The HPLC chromatogram of ethanolic crude extract presented three significant peaks with average values of RT: 13.2 min, 15.02 min, and 16.00 min whose spectra are characteristics of flavonoids. On calculating the flavonoid quantity using the average absorbance reading (A=0.874), 2.02% flavonoid was found. The concentrations for each isolated substances was 340ug for Jg1 and 406 ug for Jg2 per milliliter of extract solution. Regarding the biological activity tested AF-1 and Fr-1 inhibited growths of S. aureus and C.albicans and also manifested a great antioxidant potential. These results provide adequate polyphenol parameters for quality control serving as chemical markers and their possible quantities.
100

Propagação in vitro de pinhão-manso / In vitro propagation of Jatropha curcas

Casarin, Tatiane 04 March 2016 (has links)
Submitted by Maria Beatriz Vieira (mbeatriz.vieira@gmail.com) on 2017-09-04T15:24:28Z No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) dissertacao_tatiane_casarin.pdf: 904257 bytes, checksum: eecbe82cb3a2bcde286380eeed6592c8 (MD5) / Approved for entry into archive by Aline Batista (alinehb.ufpel@gmail.com) on 2017-09-13T17:47:27Z (GMT) No. of bitstreams: 2 dissertacao_tatiane_casarin.pdf: 904257 bytes, checksum: eecbe82cb3a2bcde286380eeed6592c8 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Approved for entry into archive by Aline Batista (alinehb.ufpel@gmail.com) on 2017-09-13T17:47:38Z (GMT) No. of bitstreams: 2 dissertacao_tatiane_casarin.pdf: 904257 bytes, checksum: eecbe82cb3a2bcde286380eeed6592c8 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2017-09-13T17:54:59Z (GMT). No. of bitstreams: 2 dissertacao_tatiane_casarin.pdf: 904257 bytes, checksum: eecbe82cb3a2bcde286380eeed6592c8 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2016-03-04 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / Com o crescente interesse a cerca do cultivo de pinhão-manso (Jatropha curcas L.), uma oleaginosa da família Euforbiaceae com potencialidade para a produção de biocombustíveis, faz-se necessária a aplicação de ferramentas biotecnológicas que tornem possível o desenvolvimento e seleção de genótipos com as características de interesse e melhores condições sanitárias. Nesse sentido, o estabelecimento de condições de cultivo e protocolos de regeneração eficientes para os genótipos de interesse local é de grande importância. O objetivo deste trabalho foi, portanto testar as condições para a propagação in vitro de pinhão-manso. Inicialmente investigou-se a otimização do processo de germinação in vitro de sementes, como fonte inicial de explantes, onde foi observado que o acréscimo de 0,94 μM de GA3 resultou em melhores médias de germinação. No protocolo de regeneração, após a modificação da composição dos meios de cultura e condições de cultivo, não foi observada diferença significativa entre os diferentes tratamentos de indução de calos, entretanto foi possível observar uma redução no desenvolvimento dos explantes que foram mantidos em condições de maior luminosidade. Para o alongamento das brotações adventícias obtidas, o tratamento mais eficiente foi T1: 9,69 μM AIA + 2,22 μM BAP. Para o enraizamento dos explantes foi utilizado meio MS com metade da concentração de sais, acrescido de 2,07 μM AIB. Foram obtidas 12 plantas regeneradas e enraizadas, entretanto estas não sobreviveram ao processo de aclimatação. Além dos ensaios de regeneração foram realizados ensaios de cultivo in vitro de ápices caulinares de plântulas germinadas in vitro, no qual se observou que a utilização de 22,2 μM de BAP + 2,07 μM de AIB + 1 g.L-1 de carvão ativado pode ser uma alternativa para a propagação da espécie. / Due to growing interest about Jatropha curcas L. cultivation, an oil crop from the Euforbiaceae family with potential for biofuel production, it is necessary to apply biotechnology tools that make possible the development and selection of genotypes with the features of interest and better health. Accordingly, the establishment of efficient culture conditions and regeneration protocols for local interest genotype is of great importance. Therefore the aim of this study was try to establish the best conditions for the in vitro propagation for genotypes from the Embrapa Clima Temperado breeding program. Initially we investigated the optimization of the process of in vitro germination of seeds, as an initial source of explants, where it was observed that the addition of 0.94 μM GA3 resulted in better average germination. About the regeneration protocol, after changing the composition of the culture media and cultivation conditions, there was no significant difference between the different callus induction treatments, though we observed a reduction in the development of explants that were maintained in more intense light. For elongation of adventitious shoots, the most effective treatment was T1: 9,69 μM AIA + 2,22 μM BAP. For the shoot rooting was used MS medium with half salt concentration plus 2.07 μM IBA. 12 regenerated and rooted plants were obtained, though these did not survive the acclimatization process Apical in vitro culture assays were performed in which it was observed that the treatment T2: 22.2 μM BAP + 2.07 μM IBA + 1 gL-1 of activated carbon can be an alternative for the propagation of the species.

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