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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.
101

Mobilização de reservas durante o estabelecimento de plântulas de pinhão manso submetidas ao estresse salino / Mobilization of reserves for the establishment of Jatropha seedlings subjected to salt stress

Lira, Emannuella Hayanna Alves de 17 February 2016 (has links)
Submitted by Jean Medeiros (jeanletras@uepb.edu.br) on 2016-05-03T14:17:39Z No. of bitstreams: 1 PDF - Emannuella Hayanna Alves de Lira.pdf: 1372178 bytes, checksum: 438b6581ece1ed43e8780c22ab7498f0 (MD5) / Approved for entry into archive by Secta BC (secta.csu.bc@uepb.edu.br) on 2016-07-25T19:30:10Z (GMT) No. of bitstreams: 1 PDF - Emannuella Hayanna Alves de Lira.pdf: 1372178 bytes, checksum: 438b6581ece1ed43e8780c22ab7498f0 (MD5) / Approved for entry into archive by Secta BC (secta.csu.bc@uepb.edu.br) on 2016-07-25T19:33:08Z (GMT) No. of bitstreams: 1 PDF - Emannuella Hayanna Alves de Lira.pdf: 1372178 bytes, checksum: 438b6581ece1ed43e8780c22ab7498f0 (MD5) / Made available in DSpace on 2016-07-25T19:33:08Z (GMT). No. of bitstreams: 1 PDF - Emannuella Hayanna Alves de Lira.pdf: 1372178 bytes, checksum: 438b6581ece1ed43e8780c22ab7498f0 (MD5) Previous issue date: 2016-02-17 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / In the present study is proposed test the hypothesis that salinity affects the mobilization of reserves for the development of Jatrophaseedlings with damage to the growth and stabilization of the seedlings. The study consisted of three experiments, where in the 1st was standardized the experimental driving time, salt dosages and the best time to collect the seedlings to be used in subsequent experiments. For this purpose, were used two genotypes of Jatropha (CNPAPM-X and CNPAPM-III) and 5 concentrations of NaCl (0; 50; 100; 150; 200 mM) applied between the 4th and 8th days after sowing. In this experiment it was found that the NaCl dose which provided the highest germination rate for the CNPAPM-X genotype was 200 mM and for CNPAPM-III genotype was 50 mM.Furthermore, it was observed that the genotype CNPAPM-X was more tolerant to salt stress, during the germination phase, than the CNPAPM-III genotype. Thus, the doses of 75 and 150 mMNaCl were defined such as moderate and severe, respectively, to be used in subsequent experiments. In experiment 2, to define the effect of salinity on the initial growth of Jatropha seedlings were evaluated the water status through the moisture percentage, relative water content, ion partition and physiological damage in membrane seedlings treated with 0; 75 and 150 mMNaCl. In this experiment it could be suggested that the water status of Jatropha seedlings is hampered by the increasing salinity, by reducing the accumulation capacity + of water by plants and this may be associated with increased content of Na especially on the stem, indicating that this part works like asaccumulator of this ion.The relationship between the effects of salinity on growth of seedlings were evaluated in the third experiment through quantification of sugars, starch, proteins, amino acids and lipids in cotyledonary leaves, stem and roots. In this experiment there was an increase in the content of all classes of macromolecules analyzed in at least one of the organs studied. This experiment concluded that the accumulation of these macromolecules in the analyzed parts could assist in osmotic adjustment process Jatrophaseedlings under salinity, although this accumulation has not been able to prevent losses in the biomass of plants. Further, it was found that salinity caused inhibition of lipid mobilization and carbon reserves, factors that together with the synthesis of proteins and amino acids contribute to the salinity tolerance of these plants. / No presente trabalho propôs-se testara hipótese de que a salinidade afeta a mobilização de reservas durante o desenvolvimento de plântulas de pinhão manso com prejuízos ao crescimento e estabilização das plântulas. A pesquisa constou de 3experimentos, onde no1°padronizou-se , as doses de sal e a melhor fase para a coleta das plântulas a serem utilizadas nos experimentos subsequentes. Para tanto, utilizou-se dois genótipos de pinhão manso (CNPAPM-X e CNPAPM- III) e 5 concentrações de NaCl (0; 50; 100; 150; 200mM) aplicados entre o 4° e 8° dia após a semeadura. Nesse experimento verificou-se que a dose de NaCl que proporcionou maior índice de germinação para o genótipo CNPAPM-X foi a de 200 mM e para o genótipo CNPAPM-III foi a de 50 mM.Ainda, observou-se que o genótipo CNPAPM-X foi mais tolerante à salinidade durante a fase germinativa do que o genótipo CNPAPM-III. Assim, definiu-se as doses de 75 e 150 mM de NaCl como tratamentos moderado e severo, respectivamente, a serem utilizados nos experimentos subsequentes. No experimento 2 para se definir o efeito da salinidade no crescimento inicial de plântulas de pinhão manso avaliou-se o status hídrico através do percentual de umidade, conteúdo relativo de água, partição iônica e os danos fisiológicos em membrana de plântulas tratadas com 0; 75 e 150 mM de NaCl. Nesse experimento é possível sugerir que o status hídrico de plântulas depinhão manso é prejudicado pelo aumento da salinidade, através de uma redução na capacidade do acumulo de água pelas plantas e que isso + pode estar associado ao aumento do conteúdo de Na principalmente no caule, indicando que este órgão funciona como acumulador deste íon. A relação entre os efeitos da salinidade no crescimento de plântulas foram avaliados no experimento 3 através da quantificação de açucares, amido, proteínas, aminoácidos e lipídios em folhas cotiledonares, caule e raízes. Nesse experimento observou-se aumento no conteúdo de todas as classe de macromoléculas analisadas em ao menos 1 dos órgão estudados.Este experimento permitiu concluir que o acúmulo dossolutos orgânicosanalisados podem auxiliar no processo de ajustamento osmótico de plântulas de pinhão manso sob salinidade, embora esse acumulo não tenha sido capaz de impedir as perdas na biomassa das plântulas.Ainda, verificou-se que a salinidade provocou inibição da mobilização de lipídios e reservas de carbono, fatores que juntamente com a síntese de proteínas e aminoácidos contribuem para a tolerância dessas plantas a salinidade.
102

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

Lívia Tereza de Andrade Souza 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.
103

Maîtrise de l'aptitude technologique des oléagineux par modification structurelle : applications aux opérations d'extraction et de transestérification in-situ

Nguyen Van, Cuong 08 November 2010 (has links) (PDF)
Le présent travail de thèse porte sur l'étude de l'impact de la texturation par DIC (Détente Instantanée Contrôlée) sur les deux opérations d'extraction d'huile et de transestérification in-situ appliquées aux graines de colza et fèves de Jatropha Curcas. Une analyse fondamentale a prouvé l'importance de la diffusion du solvant ou réactif dans la matrice solide, et permis d'identifier les processus d'intensification au travers des trois caractéristiques physiques de diffusivité effective, d'accessibilité initiale et de rendement d'extraction ; ainsi que la cinétique de transestérification in-situ et le rendement d'ester méthylique d'acides gras. Une étude phénoménologique a permis de déterminer les diverses valeurs de ces caractéristiques en fonction des paramètres opératoires DIC (pression de vapeur d'eau saturée P et temps de traitement t).Dans le cas d'extraction, la diffusivité effective (Deff) de produits traités par DIC peut atteindre 8,01 10-12 m2/s contre 0,715 10-12 m2/s pour le colza non traité et 5,90 10-12 m2/s contre 2,42 10-12 m2/s pour le jatropha non traité. Le taux d'accessibilité initiale de produits traités par DIC peut atteindre 80,53% contre 26,71% pour le colza non traité et 92,58% contre 75,91% pour le jatropha non traité. Au plan du rendement, la DIC a pu impliquer un rendement de 153% pour le colza et 112% pour le jatropha.Dans le cas de la transestérification in-situ, les rendements d'esters méthyliques d'acides gras totaux (FAME total) obtenus pour les produits traités par DIC sont systématiquement supérieurs à ceux de la matière première non traitée par DIC pour les deux cas de colza et de jatropha. Le temps de réaction a été réduit à 30 - 45 minutes contre 120 minutes pour le produit non traité par DIC (cas de colza) et à 15 minutes au lieu de 60 minutes pour le produit non traité par DIC (cas de fèves de jatropha).
104

Perception and realities of biofuels investment in rural livelihood: the case of Kisarawe district,Tanzania

Mandari, Zamda January 2010 (has links)
Increase demand for biofuel in the world as the means to mitigate global climate change, energy option and reduced fule import expenses have attracted many companies to acquire land in developing countries like Tanzania. To invest on biofuel in Africa is believed to be a means for generating incomes from expert, to employ rural people, enhance infrastructure development.However, in Africa biofuels policy is still weak. This study mainly focuses on people`s expectation during and after the investment.Issue of compensation procedure and promises seems to be a big problem; something brought tension of being cheated among local communities. Futhermore, community involvement and integration of jatropha with smallholder´s agriculture is also low.
105

Highly efficient procedure for the synthesis of biodiesel using ionic liquid as catalyst

Lin, Jia-fang 16 July 2012 (has links)
This study used jatropha oil, waste cooing oil, and soybean oil as the raw materials for investigating effects of catalyst concentration, reaction time, reaction temperature, methanol-to-oil ratio, and catalyst types on biodiesel yield. The authors also heated up the oil to speed up the transesterification and to make the reaction more complete. Jatropha oil, waste cooing oil, and soybean oil were used as the raw materials, and three types of ionic liquid or zwitterionic liquid, [PyrMe][HSO4], [PyrMeBuS][HSO4], and [MorMeA][Br], were added as catalysts for co-catalysis while heating the oil raw materials to create the best operational condition for biodiesel production. For soybean oil used as the raw material, the best catalyzing effect (a 99.4% yield) was achieved by adding [MorMeA][Br] while the reaction time was 6min, reaction temperature was 70 ¢J, and the methanol-to-oil ratio was 9:1. Under the best reaction condition, catalyzing effect was compared between the addition of sulfate-containing ionic liquid and sulfate-containing zwitterionic liquid. The yield of the addition of sulfate-containing ionic liquid and sulfate-containing zwitterionic liquid were 97.2% and 98.7% respectively. It can be found from this study that for increasing biodiesel yield, the addition of zwitterionic liquid for co-catalysis is more effective than the addition of homogeneous ionic liquid. Comparing the best operational condition between jatropha oil and soybean oil, the best yield of jatropha oil and soybean oil was 98.5% and 99.4% respectively, while the concentration of sodium hydroxide was 0.75 wt%, [MorMeA][Br] of 1.00 wt% was added, the methanol-to-oil ratio was 9:1, the reaction time was 6 min, and the reaction temperature was 70¢J. As for disposed cooking oil, the best operational condition rendered a yield of 98.1% when the concentration of sodium hydroxide was 0.75 wt%, [MorMeA][Br] of 1.00 wt% was added, the methanol-to-oil ratio was 9:1, the reaction time was 7 min, and the reaction temperature was 70¢J. For waste cooking oil, because of the containing of impurities from frying, the yield was slightly lower and the reaction time was longer.
106

A comparison of axiomatic design theory and systematic design procedure in the design of a solid state fermenter

2014 September 1900 (has links)
Design theories and methodologies are guidelines to develop design solutions. Among many, the Axiomatic design theory (ADT) and Systematic design procedures (SDP) are two well-known approaches to design. For practical applications, the choice of the design methodology is difficult as there is no study to compare them. To close in such gap in literature, this thesis presents a study on comparison of these two design approaches. To facilitate the comparison, design of a solid state fermenter was taken as a vehicle. The fermenter chosen for this study is was used for detoxification of phorbol esters from Jatropha curcas. Jatopha curcas is a woody plant and is one of the major sources for the production of bio-diesel as it is readily available and has unique composition. Processing Jatopha curcas for biodiesel also yields protein rich Jatopha curcas seed cake. This can be used as animal feedstock, cattle fodder or live feed stock. It is however known that phorbol esters present in the seed cake hinder the utilization of the seed cake as live feed stock. Solid state fermentation by fungi is an effective process to denature phorbol esters, which has been demonstrated at the laboratory scale. Development of an industrial scale solid state fermenter (SSF) is necessary. This study applies SDP and ADT the same deign problem of SSF and compared based on the result of the design. It is noted that in ADT, the evaluation of design alternatives neither considers the cost of the system under design nor the delivery time of the system, but SDP does. To make the comparison on the same ground, an extension of ADT enabling it to consider the cost and delivery time (or time) was developed. Several conclusions can be drawn from this study and they are: (1) ADT and SDP are complementary to each other and the one that integrates both is more effective to design; (2) The essence of Axiom 2 of ADT is to evaluate design alternatives with all factors that lead to difficulty to realize the design, but unfortunately the information content in the current ADT literature only considers the functional or quality aspect; (3) Previous reports suggest the presence of zigzag process only in ADT, However in this study it is evident that SDP exercises the zigzag process as well; (4) the proposed formulation of information content by taking into consideration of the quality, cost, time aspects is more effective in design practice as quite often the cost and time are very important aspects to the customer. The contribution of this thesis study is of two-fold. First, the SSF designed in this study is a pilot one in the field of the biochemical process and it has potential to be implemented. Second, this study concludes several unique findings of ADT and SDP with their relationship, which have further resulted in an integrated ADT and SDP design approach and a more complete formulation of information content capable of evaluating design alternatives from all aspects rather than the functional aspect only.
107

Promoting Sustainability in the Energy Sector in Nepal-with a Focus on Biodiesel Fuel

KC (Chhetri), Arjun Bahadur 27 August 2012 (has links)
This study analyzes the sustainability of various energy sources including micro hydro power and biodiesel in the context of Nepal. The main focus is on the development of biodiesel fuels from non-edible oil resources including waste cooking oil, jatropha and soapnut oil feedstocks grown on the marginal lands of Nepal. Biodiesel fuel samples were prepared by acid and/or base catalyst transesterification. Both single stage and dual stage transesterification processes were employed depending on the free fatty acid content of the oil feedstock. The oil to biodiesel conversion rate and total yield were monitored. The quality of the biodiesel fuels including viscosity etc was confirmed by an external laboratory and all fuels met the ASTM fuel quality requirements. Canola, jatropha and soapnut biodiesel fuels were tested to determine some atomization properties - density, surface tension and viscosity - at elevated temperatures and pressures. The density of three biodiesel fuels and diesel were determined up to 523 K and 7 MPa using a capacitance type densitometer. The results showed a linear relationship with temperature and pressure over the measured range. The experimental data were well within the range of canola and other biodiesel fuels found in the literature. Kay’s mixing rule was used to predict the density of some biodiesel blends and the results were found to be in agreement with less than 5% error with the measured data. The surface tension was measured using a pendant drop apparatus for all three biodiesel and diesel fuels for temperatures and pressures up to 473K and 7 MPa. Results showed a linear relationship with temperature as well as with pressure. Temperature has a higher effect on surface tension than pressure. The viscosity of all three biodiesel and diesel fuels were measured using a torsional vibration viscometer up to 523 K and 7 MPa. Results showed that the viscosity-temperature relationship of all three biodiesel fuels tested followed a modified Andrade equation which was also applicable when temperature and pressure were both applied simultaneously. The measured and regressed kinematic and dynamic viscosities obtained were comparable with values in the literature. / This thesis is focused on sustainability analysis of alternative fuels in Nepal and presents the resullts of the tests on fuel and atomization characterisation of different biodiesel feedstocks including canola, jatropha, soapnut and waste cooking oil. A new model to evaluate sustainability of renewable alternatives energy resources has been developed and tested.
108

Identifying optimal locations for large scale Jatropha cultivation for biodiesel production in Tanzania's semi arid regions.

Mudede, Elmah Zvanyadza. January 2009 (has links)
Rapidly increasing concerns about energy security coupled with detrimental environmental impacts posed by the dependence on fossil fuels, and an urgent need for rural development in Africa are key drivers for the search for fuel alternatives. The international effort into the development of criteria and indicators for sustainable bioenergy production clearly recognizes that bioenergy production must not be at the expense of biodiversity and food security. Owing to its multi-purpose capabilities i.e. its ability to rehabilitate eroded lands, drought resistance as well as its biophysical and maintenance requirements, Jatropha was selected as a potential candidate for the production of biodiesel. Jatropha is not new to the people of Tanzania, the study area of the project. Research has shown that, its associated social, environmental and economic benefits are crucial to economic development of the country. At present, all of Tanzania’s petroleum based products are imported; about 90% of the energy consumed is derived from biomass; road, rail and electricity networks are underdeveloped. Environmental degradation is also a concern in the country. The aim of the study was to identify three optimal locations for large scale Jatropha cultivation for biodiesel production in Tanzania’s semi arid regions. Geographical Information Systems was used to overlay several remotely sensed data from previous research namely semi arid regions delineations, agro-ecological sub-zones that had Jatropha potential as well as the administrative zones of Tanzania. The unavailable and/unsuitable areas were verified against literature and this enabled the areas that were under cultivation, were housing biodiversity or were generally constrained to be filtered out from the study area. The three largest, available and potentially suitable areas that the study identified for large scale Jatropha cultivation occupied about 7.6 million hectares. Assuming an optimal seed yield and an oil content of 35%, these areas are capable of producing about 14.4 million litres of Jatropha oil per annum. Targeting a SADC fuel import substitution of 10%, these 14.4 million litres of Jatropha oil that the three areas will meet about 83% of the country’s energy needs. Owing to the state of electricity generation in Tanzania, these three areas are able to generate about six percent of electricity and this can contribute to some extend to the country energy needs. From the analysis it was clear to note that the production of biodiesel for blending or for electricity generation is going to be economically viable from the three selected regions. The available and suitable areas that were not consolidated within the three selected regions can be used for small scale Jatropha cultivation and their produce can be fed to large scale commercial oil production or they can use the biodiesel to produce their own electricity. Jatropha will have to be irrigated to enhance a viable economic yield; infrastructure will need to be constructed to areas that are not served by roads and railway lines. All of this bodes well for enhancing rural development. The government has already had the foresight to establish the National Biofuels Task Force which will need to monitor investors to ensure no enforced human displacement and/or exploitation in areas where the large scale farms are to be established. / Thesis (M.Sc.)-University of KwaZulu-Natal, Westville, 2009.
109

Assessing the impact of growing Jatropha curcas for biofuel on the livelihood of Swaziland's rural community of Mpaka at household level.

Vilane, Patience B. 21 July 2014 (has links)
As biofuels were growing in importance, Jatropha curcas has been widely promoted as the best suitable source for biodiesel that can be exploited by developing countries .Whilst there were fears that this development may threaten food security and put a strain on other natural resources there was a view that if well managed, the activity may spur rural economic growth thereby reducing poverty and unemployment. The purpose of this study was to investigate the impact that growing Jatropha curcas for supplying the biodiesel industry has made on the livelihoods of the households that were involved within the community of Mpaka in Swaziland. The target respondents were all the farmers that had an agreement with D1 Oils Swaziland and actually planted Jatropha curcas based on the Sustainable Livelihoods framework and using qualitative techniques data were collected using documentation, semi-structured interviews, focus group discussion, and some observation. Content analysis was then carried out to document the history of growing Jatropha curcas in Swaziland; map out the vulnerability context for the community of Mpaka; identify the range of assets that create the different livelihood strategies for the different households; determine the effect of policies and institutional conditions; and describe what the stakeholder’s view of growing Jatropha curcas is. The findings of the study revealed that growing Jatropha curcas greatly reduced the households’ vulnerability to drought, crops being browsed by livestock and high cost of farming inputs. However the study also revealed that the activity did not yield the desired outcome of income generation as the project did not continue due to bad publicity coupled with a poor policy environment and lack of coordination between and within government ministries and departments. Whilst it can be concluded that that the activity had a negative impact on the households involved it showed a great potential provided government through the relevant ministries and departments creates an enabling environment of proper policies and institutions and by involving all stakeholders at the right time. / Thesis (M.Env.Dev.)-University of KwaZulu-Natal, Pietermaritzburg, 2012.
110

Crescimento, Biomassa e Nutrição Mineral Em Plantas de Pinhão-Manso {Jatropha Curcas L.) Nutridas Com Composto Orgânico / Growth and Mineral Nutrition Pinhão Manso Plants {Jatropha curcas L.) Nourished with Organic Compound

MEDEIROS, Isis Fernanda Silva. 12 June 2018 (has links)
Submitted by Rebeka Godeiro (rebeka_carvalho@hotmail.com) on 2018-06-12T14:20:14Z No. of bitstreams: 1 ISIS FERNANDA SILVA MEDEIROS - DISSERTAÇÃO CIÊNCIAS FLORESTAIS 2012.PDF: 4294341 bytes, checksum: 0d54f12af8ea5c54bef5f3ab7c0eca26 (MD5) / Made available in DSpace on 2018-06-12T14:20:14Z (GMT). No. of bitstreams: 1 ISIS FERNANDA SILVA MEDEIROS - DISSERTAÇÃO CIÊNCIAS FLORESTAIS 2012.PDF: 4294341 bytes, checksum: 0d54f12af8ea5c54bef5f3ab7c0eca26 (MD5) Previous issue date: 2012-07-31 / Capes / O pinhão-manso apresenta-se como uma opção para produção de biocombustível, no entanto não há na literatura informações suficientes sobre o manejo da cultura, bem como suas exigências nutricionais, que possam subsidiar o seu cultivo intensivo, inclusive na ótica do aproveitamento dos coprodutos gerados. Estas informações são escassas, principalmente, em razão do número reduzido de pesquisas, o que tem dificultado o conhecimento dos hábitos da espécie. Diante disso, o trabalho objetivou analisar o crescimento inicial e sua relação com os teores de macro e micronutrientes em tecidos foliares de plantas jovens de pinhão-manso {Jatropha curcas L.), cultivadas com compostos orgânicos originados de torta e casca de pinhão-manso em diferentes proporções e dosagens. Avaliou-se o efeito de dois compostos orgânicos (composto-1 (20% de torta e 80% de casca de pinhão-manso) e composto-2 (60% de torta e 40% de casca de pinhão-manso) nas doses (0, 10, 20, 30, 40 e 50% p/p), misturados ao substrato de cultivo. O composto orgânico-1 influenciou positivamente as variáveis de crescimento (altura de plantas, número de folhas, massa seca das raízes e da parte aérea) e a acumulação de nutrientes na parte aérea das plantas de pinhão-manso, enquanto que o aumento da concentração do composto-2, no substrato, afetou negativamente todas as variáveis de crescimento, assim como a acumulação de nutrientes nas plantas. Esse efeito negativo pode estar relacionado com os danos causados pelo composto, ainda não totalmente oxidado, a integridade do sistema radicular, restringindo a absorção e, consequentemente, a acumulação de nutrientes nas plantas. / The Jatropha curcas plant represents a valuable alternative in the production of biofuel; however research information about management practices as well its nutritional requirements are limited in the literature yet. Such information is needed to support both Jatropha curcas cultivation and utilization of the side products generated. The scarce information on Jatropha curcas in the literature may be explained by lack of research study on this subject what has lead to lack of knowledge regarding the plant habits. The main goal of the current research was to access the relationship between initial growth and nutrient accumulation in leaf tissue of Jatropha curcas plants fertilized with organic manures made by mixing seed cake and fruit shell in different proportions: manure-1 (20% cake and 80% shell of Jatropha curcas), manure-2 (60% cake and 40% shell of Jatropha curcas). The concentrations used were: 0, 10, 20, 30, 40 and 50% v/v, in the growth substrate. The manure-1 had a positive influence in the following growth parameters: plant height, leaf number, dry mass of root and shoot and nutrient accumulation in the shoot. On the other hand, increasing concentration of manure-2 affected negatively all parameters studied provably by changing root membrane integrity what may have affected plant nutrient uptake by the roots.

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