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Vegetable oil is one of the most widely available renewable sources of energy that can be used to meet the world’s demands. Many vegetable oils also have the advantage of containing little to no detectable amounts of nitrogen. Recently, research studies have revealed that when two liquids with different vapor pressure values are formed into droplet-like emulsions, a micro-explosion effect can happen under specific environmental conditions. Understanding the micro-explosion phenomena can help increase the efficiency of bio-emulsion combustion as well as reduce pollution levels. Many researchers have conducted experiments to find the optimal condition that induces microexplosion effects. Microexplosion is also associated with the formation of shock waves characteristic of explosions at larger scales. However, little is known about how emulsion composition and droplet size affect the micro-explosion process. Through this research, methanol-in-vegetable oil emulsion has been studied from the microexplosion point of view using custom made electric furnace equipment with a high speed camera system and an acoustic sensor system. The main goal of this study is to understand the effect of emulsion compositions, chamber temperatures, and droplet sizes on the characteristics of microexplosion. First, an n-hexadecane-in-water emulsion was prepared to validate the performance of the custom-made experimental apparatus using previous published data. Methanol-in-canola oil emulsions with different compositions were also prepared and used to compare the micro-explosion phenomena with water as a volatile compound. Microexplosion events of the blended fuels were captured using a high speed camera and an acoustic sensor. The wave signals generated by the microexplosion were analyzed after converting the signals using a Fast Fourier Transform coded in Matlab. One of the major findings of this research work was that higher temperatures and higher concentrations of high vapor pressure fluids such as methanol and water in emulsions causes a high probability of microexplosion event due to the sudden expansion of the emulsified fluid. Also, the effect of size on microexplosion was evident in the greater probability of explosion. Methanol-in-canola oil emulsion with 15 % methanol with droplets size of 200 m placed in a furnace chamber heated to 980 ˚C showed optimal microexplosion behavior based on the formation of fine droplets. Also, smaller droplets produced higher frequencies, which could be used to detect microexplosion without high speed imaging. When large droplets microexploded, lower frequencies were detected in all the blends.

This work investigated the consequences of vegetable oils spills in salt marsh sediments. The role of autochthonous bacteria in the oils degradation and degradative pathways were also studied 'in situ' and 'in vitro'. Simulated spills of sunflower and linseed oils revealed that both oils penetrated the sediments at a rate of 10-7 CM2 s-1. However, whereas 60% of the linseed oil had disappeared from the sediments after 2 months most of the sunflower oil remained after 6 months. Differences were noted in the adsorption of the oils to sediment particles and the depth at which they accumulate and these factors most likely influenced the route of the oil degradation and the sediments properties such as permeability. The contamination of the sediments with vegetable oils lead to a noticeable reduction in the abundance of plant roots and infauna. The abundance of aerobic, anaerobic and sulphate reducing bacteria in the sediments was increased by the addition of both oils, with linseed oil supporting greater bacterial density than sunflower oil. During the course of the experiment the relative abundance of oil degrading bacteria also increased. As a consequence of the increased bacterial activity, the sediments pH and Eh decreased and anoxic conditions were established, earlier in the case of linseed than that of sunflower oils. The degradation of the oils appeared to be a sequential process, initiated by the aerobic and/or anaerobic bacteria and continued by the sulphate reducing bacteria which themselves where unable to utilise the raw oils. The original composition of both oils underwent alterations mostly associated with their main fatty acid: the concentration of 18: 3(o3 and 18: 2o)6 in linseed and sunflower oil, respectively, decreased whereas that of the remaining fatty acids increased. As a result of the bacterial degradation of the vegetable oils 'new' fatty acids were detected and their identification was attempted using GC-MS analysis of their picolinyl and methyl esters. Various degradative pathways of linseed and sunflower oils involving the formation of the 'new' fatty acids are suggested with isomerisation, hydrogenation and P-oxidation as the primary routes for the degradation.

Dissertation submitted in compliance with the requirements for the Masters Degree in Technology: Biotechnology, Durban Institute of Technology, 2003. / Water is a precious and very valuable resource. Water resource shortages are problems that are plaguing the world. There is therefore a high demand for tightening water quality standards for both potable water and waters in the environment. It is becoming a necessity to treat and reuse wastewaters, especially wastewaters from industries, as these waters are of concern due to their toxic effects on the environment. In South Africa one of the industries of major concern is that of the edible oil industry and there are over a dozen ofthese industries in South Africa alone. Each of these industries utilises approximately 1.75 million m3 of water and discharges approximately 0.61 million m3 to the sewer each year. This wastewater that is being released has very high organic, inorganic and fats, oils and greases loads. Depending on the type of refinery process conducted on the crude oil, the effluent quality and quantity varies on a day to day basis. The two types of refinery procedures are the physical refining, where water is used or chemical refining where caustic soda is used. The organic load ofthe untreated effluent can range from 1 100 to 8 990 mg COD/L, the oils and greases can range from 80 to 1 360 mg/L and the pH can range from 1.8 to 10.5. / M

Dissertation submitted in compliance with the requirements for the Master's Degree in Technology: Biotechnology, Technikon Natal, 2001. / The vegetable oil industry produces effluent containing quantities of fat, oil, sodium, phosphates as well as other pollutants. Oils and greases tend to clog sewers and pumps, thus creating difficulties within the municipal wastewater treatment works. Physico-chemical treatment methods, such as (Dissolved Air Flotation) OAF, gravity separation and the use of coagulants have been attempted providing a considerable reduction in organic loading; however, discharge standards are still not met. Thus, biological treatment methods are being sought after. Aerobic treatment has been attempted however, shock loads cause problems while running such a process. The objective of this study was to assess the efficiency of anaerobic digestion to degrade Vegetable Oil Effluent (VOE) as well as the efficiency of the Anaerobic Baffled Reactor (ABR). Anaerobic digestion involves the breakdown of organic matter by the action of microorganisms in the absence of oxygen, producing methane-rich biogas. The VOE was characterized, providing significant information on its chemical composition. It was found that the effluent had high sulphate content as well as a high COD content. High sulpahte content of wastewaters have known to promote growth of Sulphate Reducing Bacteria (SRB), which utilize the same energy source as Methane Producing Bacteria (MPB) and therefore compete for the same energy source. Sulphate and lipid reduction pretreatment experiments were carried out, using barium chloride and gravitational separation respectively. The results obtained, showed that the use of barium chloride to reduce sulphate content in VOE was successful, with significant sulphate reduction. The lipid reduction experiments however, did not show any significant lipid reduction. Batch tests were conducted in serum bottles to assess the extent of biodegradation of the VOE in its raw state as well as with reduced sulpahte content. Methanogenic toxicity tests on the raw and pretreated VOE provided a range of toxicity results. These assays are relatively simple and inexpensive. Gas production was monitored to determine the rate and extent of biodegradation. The efficiency of digestion was assessed by COD reduction. Results indicated potential inhibition of the methanogenic bacteria responsible for methane production by the / M

As patologias que acometem os membros superiores são bastante incapacitantes para os seres humanos, pois elas são sua principal ferramenta de interação com o mundo tanto pelo papel nas tarefas cotidianas quanto pelo simbolismo que carregam. Na Terapia Ocupacional o objetivo é promover uma melhor qualidade de vida, maior autonomia e participação no cotidiano e, dentre os recursos e abordagens possíveis no processo de reabilitação, as órteses têm grande destaque, pois seu uso correto pode \"aumentar a função, prevenir ou corrigir deformidade, proteger estruturas em processo de cicatrização, restringir o movimento e permitir o crescimento ou remodelação tecidual\" (FESS, 2002, p.98). As órteses mais utilizadas na prática clínica são confeccionadas em material termomoldável de baixa temperatura. Não há opções nacionais deste material, implicando na necessidade de importação que pode gerar dificuldades no acesso a este tipo de material. Leite (2007) desenvolveu um poliuretano derivado do óleo vegetal (mamona) que se mostrou apto para a confecção de órteses após ensaios mecânicos, térmicos e clínicos, mas que necessita de melhorias, principalmente em relação aos aspectos de maleabilidade (moldabilidade) e memória do material. O presente trabalho tem como objetivos caracterizar o material desenvolvido e alguns existentes no mercado e modificar o material desenvolvido por Leite (2007). Para tanto, foram introduzidas modificações - acréscimo de cargas e mudanças na proporção poliol e pré-polímero - e realizados ensaios mecânicos e térmicos de Memória, Dureza, Moldabilidade, Análise Dinâmico-Mecânica, Tração, Temperatura no Contato com a Pele Humana e a velocidade de Resfriamento do material. Os resultados indicam que o acréscimo de Sílica Pirogênica e o aumento da proporção de poliol em relação ao pré-polímero melhoraram a moldabilidade do material e tornaram a memória adequada aos propósitos. Conclui-se que o novo material, o compósito CPU POS, é mais rígido que os importados, suportando maior carga, é seguro para o paciente do ponto de vista de temperatura e possui uma grande validade. A moldabilidade é rápida e necessita que o terapeuta posicione o material, pois ele não se acomoda com a ação da gravidade. A dureza foi diminuída, embora ainda seja maior que a dos materiais de comparação. Assim, o presente estudo contribuiu para um maior conhecimento dos termomoldáveis existentes no mercado utilizados para confecção de órteses e aponta o poliuretano derivado de óleo vegetal, modificado com cargas, como um material adequado para este propósito. / Pathologies that affect the upper limbs are very incapacitating to humans, because they are your primary tool for interaction with the world, both thé role of everyday tasks as the symbolism they carry. In Occupational Therapy the objective is promote a better quality of life, more autonomy and participation in daily life and, among the resources and possible approaches in the rehabilitation process, the orthosis have great prominence, because their correct use can \"enhance function, prevent or correct deformities, protect structures in the healing process, restrict movement and support the growth or tissue remodeling\" (FESS, 2002, p.98). The most used orthosis in clinical practice are fabricated with low temperature thermoplastic. There are no national options of this material, resulting in import which can create difficulties in accessing this type of material. Leite (2007) developed a vegetable (castor) oil based polyurethane that proved suitable for orthosis, after mechanical, thermal and clinical testing, but needs improvements especially aspects of malleability (moldability) and memory of the material. The current work aims at characterizing the material developed and some of the existing materials and modify the material developed by Leite (2007). Therefore, changes have been introduced - increase of fillers and changes in the proportion polyol to prepolymer - and performed mechanical and thermal tests of Memory, Hardness, Moldability, Dynamic Mechanical Analysis, Traction, Temperature in contact with human skin and the speed Cooling the material. The results indicate that the addition of Pyrogenic Silica and increased proportion of polyol in relation to the prepolymer improved moldability ofthe material and made appropriate memory to the purpose. We conclude that the new material, composite CPU POS, is more rigid than the imported, supporting higher load, it is safe for the patient in terms of temperature and has a great validity. The moldability is fast and requires the therapist to position the material, because it does not settle by gravity. The hardness was decreased, although it is still higher than the comparison material. Thus, the present study contributed to a better understanding of existing market thermoformables used for orthosis and points the polyurethane derived from vegetable oil, modified with fillers, as a suitable material for this purpose.

Os óleos vegetais são matérias primas de fontes renováveis. São metabolizáveis, biodegradáveis, de fácil disponibilidade e baixo custo. A necessidade de adjuvantes vacinais seguros e que possam modular a resposta imunológica Th1/Th2, favorece a busca por novas substâncias que assim se comportem. Este trabalho tem o objetivo de avaliar e identificar óleo vegetal capaz de mimetizar ação adjuvante dos óleos minerais comercialmente usados e modular a resposta imune. Foram realizados testes de toxicidade aguda in vivo, testes de formação de emulsões, de estabilidade, de qualidade e, por fim, de imunogenicidade com formulações com o vírus rábico. Algumas formulações derivadas dos óleos de girassol, canola e buriti se mostraram não tóxicas, estáveis e de boa qualidade. Os grupos de camundongos inoculados com estas formulações obtiveram respostas imunológicas que apoiam sua capacidade adjuvante, não diferenciando significativamente (p<0,05) dos resultados do óleo mineral comercial. Concluiu-se que é possível elaborar emulsões estáveis não tóxicas a partir de óleos vegetais para sua utilização como veículos e adjuvantes vacinais. Formulações vacinais em forma de emulsões de óleos vegetais, compostas na sua maior parte pelos óleos de girassol e de canola possuem potência e atividade adjuvante semelhantes e tão eficientes quanto aos do óleo mineral. Os óleos vegetais devem estar em seu estado bruto ou semirrefinado, sem a adição de antioxidantes e conservantes. Por último, parece haver uma tendência de equilíbrio de resposta Th1/Th2 para as formulações com óleos vegetais. / Vegetable oils are renewable raw materials. These substances are metabolizable, biodegradable, of easy availability and low cost. The need for safe vaccine adjuvants that can modulate the Th1/Th2 immune response drives the search for new substances with similar behavior. This study aims to evaluate and identify a vegetable oil able to mimic the adjuvant action of the mineral oils used commercially, and modulate the immune response. There were performed tests of in vivo acute toxicity, emulsion formation, stability, quality and immunogenicity with formulations with rabies virus. Some formulations derived from the sunflower, canola and buriti oils proved to be non-toxic, stable and of good quality. Groups of mice inoculated with these formulations had immune responses supporting their adjuvant capacity, not differing significantly (p <0.05) from the results of the commercial mineral oil. It was concluded that it is possible to prepare stable non-toxic emulsions from vegetable oils to be used as vaccine adjuvants and vehicles. Vaccine formulations as emulsions from vegetable oil, composed mostly by the oils of sunflower and canola had adjuvant activity and potency similar to and as effective as the mineral oil. The vegetable oils should be in its raw state or semi refined, without the addition of antioxidants and preservatives. Finally, there seems to be a tendency to balance Th1/Th2 response by formulations with vegetable oils.

Os óleos vegetais são matérias primas de fontes renováveis. São metabolizáveis, biodegradáveis, de fácil disponibilidade e baixo custo. A necessidade de adjuvantes vacinais seguros e que possam modular a resposta imunológica Th1/Th2, favorece a busca por novas substâncias que assim se comportem. Este trabalho tem o objetivo de avaliar e identificar óleo vegetal capaz de mimetizar ação adjuvante dos óleos minerais comercialmente usados e modular a resposta imune. Foram realizados testes de toxicidade aguda in vivo, testes de formação de emulsões, de estabilidade, de qualidade e, por fim, de imunogenicidade com formulações com o vírus rábico. Algumas formulações derivadas dos óleos de girassol, canola e buriti se mostraram não tóxicas, estáveis e de boa qualidade. Os grupos de camundongos inoculados com estas formulações obtiveram respostas imunológicas que apoiam sua capacidade adjuvante, não diferenciando significativamente (p<0,05) dos resultados do óleo mineral comercial. Concluiu-se que é possível elaborar emulsões estáveis não tóxicas a partir de óleos vegetais para sua utilização como veículos e adjuvantes vacinais. Formulações vacinais em forma de emulsões de óleos vegetais, compostas na sua maior parte pelos óleos de girassol e de canola possuem potência e atividade adjuvante semelhantes e tão eficientes quanto aos do óleo mineral. Os óleos vegetais devem estar em seu estado bruto ou semirrefinado, sem a adição de antioxidantes e conservantes. Por último, parece haver uma tendência de equilíbrio de resposta Th1/Th2 para as formulações com óleos vegetais. / Vegetable oils are renewable raw materials. These substances are metabolizable, biodegradable, of easy availability and low cost. The need for safe vaccine adjuvants that can modulate the Th1/Th2 immune response drives the search for new substances with similar behavior. This study aims to evaluate and identify a vegetable oil able to mimic the adjuvant action of the mineral oils used commercially, and modulate the immune response. There were performed tests of in vivo acute toxicity, emulsion formation, stability, quality and immunogenicity with formulations with rabies virus. Some formulations derived from the sunflower, canola and buriti oils proved to be non-toxic, stable and of good quality. Groups of mice inoculated with these formulations had immune responses supporting their adjuvant capacity, not differing significantly (p <0.05) from the results of the commercial mineral oil. It was concluded that it is possible to prepare stable non-toxic emulsions from vegetable oils to be used as vaccine adjuvants and vehicles. Vaccine formulations as emulsions from vegetable oil, composed mostly by the oils of sunflower and canola had adjuvant activity and potency similar to and as effective as the mineral oil. The vegetable oils should be in its raw state or semi refined, without the addition of antioxidants and preservatives. Finally, there seems to be a tendency to balance Th1/Th2 response by formulations with vegetable oils.