No description available.

Atomization characteristics of liquid fuel sprays control combustion efficiency and emissions in engines. The present work is motivated by the need to study the atomization and spray structure of vegetable oil biofuels for which no data in the literature exists. In this work, various laser-based diagnostic techniques such as laser shadowgraphy, Particle/Droplet Image Analysis (PDIA) and Laser Sheet Dropsizing (LSD) are applied for studying atomization characteristics, tip penetration, droplet size and liquid volume fraction of Pongamia vegetable oil (SVO) and its blends with diesel. A constant volume high pressure spray visualization chamber is designed and fabricated to study SVO sprays at high gas pressure and temperature conditions. This optical chamber can be used for gas pressures up to 60 bar and temperatures up to 600 K. Optical access inside the chamber is provided through four quartz windows to perform various optical spray diagnostic studies. A high pressure spray injection facility based on components of common rail diesel injection system is designed. This facility can provide an injection pressure of up to 1700 bar with independent control over injection duration and timing. A marked difference is observed between diesel and SVO spray structures under atmospheric gas pressure condition. A very interesting observation related to the behavior of 100% SVO fuel when sprayed into atmospheric pressure is the presence of an intact liquid core even at injection pressure as high as 1600 bar. The presence of liquid core at high injection pressures is attributed to the high viscosity of SVOs and the non-Newtonian behavior of these oils under high pressure and shear. The spray characterization of the oil and its blends at high gas pressure shows that although the atomization is dramatically different from that at atmospheric gas pressure, it is still incomplete even at very high injection pressures. For a gas pressure of 30 bar, it is observed that the Sauter Mean Diameter (SMD) for Pongamia oil is more than twice that of diesel. A new method of simultaneously obtaining two-dimensional droplet size and quantitative liquid volume fraction data in sprays has been developed. Measurements with this method reveal a higher liquid volume fraction at the central axis of spray for Pongamia oil compared to that of diesel indicating potentially poor air-fuel mixing. The experimental data obtained and the spray tip penetration correlations developed for the vegetable oils and blends serve as useful inputs for fuel injection and engine system designers.

Dissertation submitted in fulfilment with the requirements for the Masters Degree: Biotechnology, Durban University of Technology, 2011. / Untreated vegetable oil effluents (VOEs) are known for creating shock-loading problems for the receiving wastewater treatment installations, resulting in poor quality final effluents being produced which do not satisfy municipal discharge standards. Onsite activated sludge treatment as an alternative has not been fully investigated. Hence, in this investigation biological treatment using the activated sludge process was chosen as the method for the treatment of VOE. The effect of VOE on measured process parameters was also determined. Novel molecular techniques such as fluorescent in situ hybridisation (FISH) and dot-blot hybridization have become powerful tools for the analysis of complex microbial communities that exist within activated sludge. The aim of this investigation was to evaluate biological treatment, optimize and apply FISH and dot-blot hybridization in order to analyze the microbial community implicated the biological treatment of VOE using probes EUBmix, ALF1b, BET42a, GAM42a and HGC69a. A laboratory-scale modified Ludzack-Ettinger (MLE) process setup and fed VOE with a COD (chemical oxygen demand) of ± 1000 mg/L. Daily monitoring of the process involved COD and TKN (total kjeldahl nitrogen) analysis of the influent and effluent as well as direct OUR (oxygen utilization rate) measurement and monitoring of the MLVSS (mixed liquor volatile suspended solids) concentration of the aerobic mixed liquor. The process exhibited overall COD and TKN removal capacities of 84% and 90% respectively. The aerobic mixed liquor had an OUR of 19 mgO/L.h and an average MLVSS concentration of 3000 mg/L. FISH results revealed that 72% of cells stained with 4‟, 6-diamidino-2-phenylindole (DAPI) within the aerobic mixed liquor bound to probe EUBmix, indicating a substantial Bacterial population within the laboratory-scale biological process. The alpha-Proteobacteria was identified as the dominant bacterial community comprising 31% of Bacterial cells, followed by the beta-Proteobacteria (17% of EUBmix), gamma-Proteobacteria (8% of EUBmix) and Actinobacteria (4% of EUBmix). Results of dot-blot hybridization were in agreement with FISH Adrian Phillip Degenaar| CHAPTER 1: General Introduction - v - results reiterating dominance of the alpha-Proteobacteria. This indicated that the class alpha-Proteobacteria could play a primary role in the biological degradation of VOE. This research will therefore aid in process design and retrofitting of biological processes treating VOE.

<p>Hemijskim transformacijama se iz biljnih ulja dobijaju vredni &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; derivati, poput epoksidovanih biljnih ulja, koji se<br />koriste u hemijskoj i polimernoj industriji. Kvalitet, pa<br />time i primena epoksidovanih biljnih ulja, zavise od<br />sadržaja epoksidnih grupa u derivatizovanom ulju, koji bi<br />trebalo da je &scaron;to veći. Kako epoksidne grupe nastaju<br />oksidacijom dvostrukih veza u trigliceridima kao<br />dominantnoj grupi jedinjenja u biljnim uljima, pogodna<br />sirovina za epoksidovanje su visoko nezasićena ulja,<br />kakvo je laneno.<br />Proizvodnja epoksidovanih biljnih ulja zahteva izbor<br />takvih procesnih uslova pri kojima bi se postigli &scaron;to<br />potpunija konverzija dvostrukih veza i &scaron;to veća<br />selektivnost procesa u odnosu na epoksidnu grupu. Zato je<br />kao cilj ove doktorske disertacije postavljeno određivanje<br />optimalnih vrednosti procesnih uslova epoksidovanja<br />lanenog ulja persirćetnom kiselinom formiranom in situ iz<br />sirćetne kiseline i 30% vodenog rastvora vodonik<br />peroksida u prisustvu jonoizmenjivačke smole kao<br />katalizatora. Određivanje je izvedeno primenom<br />metodologije odzivne povr&scaron;ine, kao i kori&scaron;ćenjem u ovoj<br />disertaciji predloženih kinetičkih modela ispitivanog<br />reakcionog sistema, u oba slučaja sa maksimumom<br />relativnog prinosa epoksida kao funkcijom cilja.<br />Ispitivanje uticaja procesnih uslova, i to temperature,<br />molskog odnosa reaktanata, količine katalizatora i brzine<br />me&scaron;anja, na tok procesa epoksidovanja je bilo osnov za<br />definisanje graničnih vrednosti procesnih uslova unutar<br />kojih je tražen maksimum prinosa epoksida. Oblast dugih<br />vremena reagovanja, koja nije od interesa za industriju, je<br />izbegnuta adekvatnim izborom temperature.<br />Pri optimalnim vrednostima procesnih uslova<br />epoksidovanja lanenog ulja, određenim primenom<br />metodologije odzivne povr&scaron;ine, postignuto je dobro<br />slaganje očekivane i eksperimentalno određene vrednosti<br />maksimalnog relativnog prinosa epoksida, sa odstupanjem<br />od 3,28%.<br />Za potrebe određivanja optimalnih uslova izvođenja<br />procesa epoksidovanja biljnih ulja kori&scaron;ćenjem kinetičkih<br />modela, razvijena su tri pseudohomogena modela<br />ispitivanog trofaznog multireakcionog sistema. Pored<br />kinetike osnovnih reakcija formiranja persirćetne kiseline i&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; reakcije epoksidovanja dvostrukih veza triglicerida biljnog ulja,&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; kao i kinetike sporedne reakcije otvaranja epoksidne<br />grupe sa sirćetnom kiselinom, u predloženim modelima je<br />uzeta u obzir i raspodela sirćetne i persirćetne kiseline<br />između uljne i vodene faze sistema. Opisan je i uticaj<br />masno-kiselinskog sastava ulja, odnosno broja dvostrukih<br />veza u masno-kiselinskim lancima triglicerida, na kinetiku<br />reakcija. Za koeficijent raspodele sirćetne kiseline između<br />tečnih faza reakcionog sistema predložena je empirijska<br />korelacija koja je dala dobro slaganje izračunatih<br />vrednosti sa eksperimentalnim podacima. Kinetički<br />parametri modela su određeni fitovanjem<br />eksperimentalnih podataka o promenama količina<br />dvostruke veze i epoksidne grupe sa vremenom izvođenja<br />procesa epoksidovanja. Na osnovu statističkih pokazatelja<br />uspe&scaron;nosti fitovanja eksperimentalnih podataka, potvrđena<br />je prepostavka da je pseudohomogeni model publikovan u<br />literaturi unapređen uzimanjem u obzir pomenutih<br />fenomena raspodele komponenata reakcione sme&scaron;e i<br />masno-kiselinskog sastava sirovine pri modelovanju<br />reakcionog sistema epoksidovanja biljnih ulja<br />persirćetnom kiselinom.<br />Kori&scaron;ćenjem predloženih pseudohomogenih modela<br />reakcionog sistema za određivanje optimalnih uslova<br />izvođenja procesa epoksidovanja lanenog ulja in situ<br />formiranom persirćetnom kiselinom u prisustvu<br />jonoizmenjivačke smole, dobijeno je odstupanje od 5,51%<br />očekivane od eksperimentalno određene vrednosti<br />relativnog prinosa epoksida.<br />Bolje slaganje predviđene sa eksperimentalno određenom<br />vredno&scaron;ću relativnog prinosa epoksida u kontrolnom<br />eksperimentu je dobijeno primenom metodologije odzivne<br />povr&scaron;ine u poređenju sa kori&scaron;ćenjem kinetičkih modela pri<br />određivanju optimalnih vrednosti procesnih uslova. To je i<br />očekivano, s obzirom da regresiona jednačina kori&scaron;ćena u<br />okviru metodologije odzivne povr&scaron;ine bolje fituje relativni<br />prinos epoksida. Standardna devijacija relativnog prinos<br />epoksida za regresionu jednačinu je 8,9 puta niža od one<br />izračunate za kinetički model koji najbolje predviđa<br />optimalne procesne uslove epoksidovanja lanenog ulja<br />persirćetnom kiselinom.</p> / <p>Vegetable oils can be transformed into added value<br />products by various chemical modifications, such as<br />epoxidation. The epoxidized vegetable oils have a<br />wide range of applications in the chemical and<br />polymer industry. The quality, and consequently the<br />application, of epoxidized vegetable oil is influenced<br />by the epoxy group content. Since the epoxy groups<br />are formed by the oxidation of double bonds in<br />triglycerides, the main constituent of vegetable oils,<br />highly unsaturated vegetable oils, such as linseed<br />oil, are desirable raw materials.<br />The manufacturing of epoxidized vegetable oils<br />requires the optimization of the process conditions<br />in order to achieve complete conversion of double<br />bonds and high selectivity of the process in respect<br />to the epoxy groups. Therefore, the aim of this<br />doctoral thesis is to determine the optimal process<br />conditions for the epoxidation of linseed oil with<br />peracetic acid, formed in situ from acetic acid and<br />30% hydrogen peroxide in the presence of an ion<br />exchange resin as the catalyst. The optimal process<br />conditions were determined by response surface<br />methodology, as well as by using developed pseudohomogeneous<br />kinetic models that describe the<br />investigated reaction system. For both optimization<br />methods, the relative epoxy yield was selected as an<br />objective function to be maximized.<br />The effects of process conditions, such as<br />temperature, molar ratio of reactants, catalyst<br />amount and steering speed, on the kinetics of the<br />epoxidation were studied in order to define<br />constraints for the optimization. To avoid long<br />reaction times, which are not of interest in<br />manufacturing, an adequate temperature range was<br />selected. Under the optimized process conditions for the<br />epoxidation of linseed oil, which were determined<br />by response surface methodology, good agreement<br />between the calculated and experimentally<br />determined relative epoxy yields was achieved<br />within 3.28%.<br />Three models describing the three-phase multireaction<br />system of vegetable oil epoxidation with<br />peracetic acid were developed and further used for<br />the optimization. The models are pseudohomogeneous<br />with respect to the catalyst. Besides<br />the kinetics of the main reactions of peracetic acid<br />and epoxy group formation, the models take into<br />account the side reaction of the epoxy group opening<br />with acetic acid. The partitioning of the acetic acid<br />and peracetic acid between the oil and aqueous<br />phases is considered. In two proposed models, the<br />effect of fatty acid composition on the kinetics of the<br />process is also described by considering the number<br />of double bonds in the fatty acid chains. The<br />developed empirical correlation for the partition<br />coefficient for acetic acid between the liquid phases<br />shows good agreement between the calculated and<br />experimental data. The kinetic parameters of the<br />proposed pseudo-homogeneous models were<br />determined by fitting the experimentally determined<br />changes of the double bond and epoxy group<br />amounts with reaction time of the epoxidation.<br />Statistical values of the models` parameters<br />determination confirmed the hypothesis that the<br />pseudo-homogeneous model proposed in the<br />literature can be improved by considering the<br />partitioning phenomena and the effect of the oil fatty<br />acid composition on the kinetics of the vegetable<br />oils epoxidation with peracetic acid.<br />Under the optimized process conditions for the<br />epoxidation of linseed oil with peracetic acid formed<br />in situ in the presence of the ion exchange resin,<br />which were determined by using proposed pseudohomogeneous<br />models, the experimentally<br />determined relative epoxy yield was 5.51% lower<br />than the calculated.<br />Better agreement between the calculated and<br />experimentally determined values for the relative<br />epoxy yield, achieved under the optimal process<br />conditions, is obtained when the response surface<br />methodology (RSM) was applied as opposed to<br />when the kinetic models were used for the<br />determination of the optimal process conditions.<br />This is in accordance with better fitting of the<br />relative epoxy yield by RSM regression equation<br />than by kinetics models. Standard deviation of the<br />relative epoxy yield for RSM regression equation is 8.9 times lower than the standard deviation for the<br />most successful kinetic model used for prediction of<br />the optimal process conditions for the epoxidation of<br />the linseed oil by peracetic acid.</p>

Biodiesel and hydrotreated vegetable oil (HVO) are currently viewed by the transportation sector as the most viable alternative fuels to replace petroleum-based fuels. The use of biodiesel has, however, been limited by the deteriorative effect of biodiesel on rubber parts in automobile fuel systems. This work therefore aimed at investigating the degradation of acrylonitrile butadiene rubber (NBR) and fluoroelastomers (FKM) on exposure to biodiesel and HVO at different temperatures and oxygen concentrations in an automated ageing equipment and a high-pressure autoclave. The oxidation of biodiesel at 80 °C was promoted by an increase in the oxygen partial pressure, resulting in the formation of larger amounts of hydroperoxides and acids in the fuel. The fatty acid methyl esters of the biodiesel oxidized less at 150 °C on autoclave aging, because the termination reactions between alkyl and alkylperoxyl radicals dominated over the initiation reactions. HVO consists of saturated hydrocarbons, and remained intact during the exposure. The NBR absorbed a large amount of biodiesel due to fuel-driven internal cavitation in the rubber, and the uptake increased with increasing oxygen partial pressure due to the increase in concentration of oxidation products of the biodiesel. The absence of a tan δ peak (dynamical mechanical measurements) of the bound rubber and the appearance of carbon black particles devoid of rubber suggested that the cavitation was caused by the detachment of bound rubber from particle surfaces. A significant decrease in the strain-at-break and in the Payne-effect amplitude of NBR exposed to biodiesel was explained as being due to the damage caused by biodiesel to the rubber-carbon-black network. During the high-temperature autoclave ageing, the NBR swelled less in biodiesel, and showed a small decrease in the strain-at-break due to the cleavage of rubber chains. The degradation of NBR in the absence of carbon black was due only to biodiesel-promoted oxidative crosslinking. The zinc cations released by the dissolution of zinc oxide particles in biodiesel promoted reduction reactions in the acrylonitrile part of the NBR. Heat-treated star-shaped ZnO particles dissolved more slowly in biodiesel than the commercial ZnO nanoparticles due to the elimination of inter-particle porosity by heat treatment. The fuel sorption was hindered in HVO-exposed NBR by the steric constraints of the bulky HVO molecules. The extensibility of NBR decreased only slightly after exposure to HVO, due to the migration of plasticizer from the rubber. The bisphenol-cured FKM co- and terpolymer swelled more than the peroxide-cured GFLT-type FKM in biodiesel due to the chain cleavage caused by the attack of biodiesel on the double bonds formed during the bisphenol curing. The FKM rubbers absorbed biodiesel faster, and to a greater extent, with increasing oxygen concentration. It is suggested that the extensive biodiesel uptake and the decrease in the strain-at-break and Young’s modulus of the FKM terpolymer was due to dehydrofluorination of the rubber by the coordination complexes of biodiesel and magnesium oxide and calcium hydroxide particles. An increase in the CH2-concentration of the extracted FKM rubbers suggested that biodiesel was grafted onto the FKM at the unsaturated sites resulting from dehydrofluorination. / <p>QC 20170227</p>

Os pesticidas fazem parte do conjunto de tecnologias associadas à modernização da agricultura e com o uso generalizado destes muitos problemas começaram a ser diagnosticados, entre eles, a contaminação de solos e água. A permanência no ambiente está relacionada às características físico-químicas destes produtos, bem como as do ambiente, que definem processos de transporte, retenção e transformação entre compartimentos ambientais. Em âmbito mundial, o emprego de técnicas que visem a minimizar o número de aplicações, produtos que possibilitem uma degradação microbiana mais rápida e síntese de produtos com menor potencial de contaminação ambiental pode vir a corroborar no processo de racionalização e segurança do uso de pesticidas, como também preservar a biodiversidade da microbiota do solo. Os espalhantes adesivos são empregados na agricultura como adjuvantes na aplicação de pesticidas. Até o presente momento se conhecem estudos de eficácia de controle de agentes nocivos na presença e ausência de adjuvantes, mas pouco se conhece dos efeitos combinados dos mesmos com pesticidas no ambiente. Este estudo teve como objetivo verificar o efeito do óleo vegetal na persistência de endosulfan, inseticida que apresenta uso relevante em culturas de importante projeção no setor de agronegócios no Brasil. A priori foi conduzido um teste para selecionar o óleo mais adequado entre soja e girassol, sob processos degomado e refinado utilizando-se placas com meio de cultura e inoculação com Aspergillus sp (CAD G1), onde se observou um aumento de 81,07% do crescimento da colônia na presença do óleo de soja degomado e endosulfan (OSDu+E+I) comparado a ausência do óleo de soja (E+I). Diante dos resultados apresentados optou-se pelo óleo de soja degomado, cujo produto comercial é o Natur’l Oil. Os processos supracitados foram avaliados através de estudos de transformação de carbono e nitrogênio por microrganismos do solo, de lixiviação e biodegradabilidade em solos, testando as seguintes concentrações: DMA (700 g de endosulfan/ha) e DMA+O (700 g de endosulfan/ha misturado a 2L/ha de Natur’l Oil). Os resultados mostraram que estatisticamente não houve diferenças nos testes de transformações de carbono e nitrogênio, como biodegradabilidade em solos, quando comparados os tratamentos na ausência e presença do Natur’l Oil. Os resultados do teste de lixiviação mostram os seguintes percentuais de endosulfan: 91,68 e 66,04 no solo e para o lixiviado 5,18 e 4,98 nos tratamentos DMA e DMA+O, respectivamente. Os valores de lixiviado não diferiram entre si estatisticamente, no entanto no solo observou-se que a presença do Natur’l Oil promove uma menor adsorção do endosulfan e maior dissipação. Tendo em vista que a presença do Natur’l Oil não interfere nos processos de transformação de carbono e nitrogênio e no teste de biodegradabilidade do endosulfan em solos e que no processo de lixiviação a presença do óleo trouxe incrementos positivos, desfavorecendo a percolação do pesticida, a adição de óleos vegetais, como espalhante adesivo, deve ser considerada na aplicação de pesticidas para redução de lixiviação e por evitar o contato direito dos pesticidas com os microrganismos de solo, proporcionando uma maior fase lag e a preservação da biodiversidade. / The pesticides make part of a technology that is associated to the agriculture modernization. With their generalized use many problems occur and are diagnosed, among others, the water and soil contamination. The persistence in the environment is related to their physical and chemical properties, as well to the environment that defined the transport, retention and transformation processes in environment compartments. In world wide point of view, techniques that try to minimize the number of applications, the use of products that possibility a fast microbial degradation and synthesis of products with lower potential to the environmental contamination can help the rationalization process and safer use of pesticides, in order to preserve the biodiversity of the soil microbiota. The adhesive dispersed are used in agriculture as adjuvants to the pesticide application. Until now efficacy control studies in harmful agents with pesticides in the presence and absent of adjuvants have been known, but there are few knowledge about their combined effects in the soil. This study had the objective to verify the effect of vegetable oil in the persistence of the endosulfan, the inseticide that shows a considerable use in cultures with important projection in the Brazil agribusiness sector. At first a test was conducted to select the more suitable oil, between soybean and sunflower, under degumming and refined processes using plates with culture medium and inoculated with fungi Aspergillus sp (CAD G1). In the plates test observed that the colony diameter increased in 81.07% in the presence of the soybean degumming oil and endosulfan (OSDu+E+I) compared with the absence soybean degumming oil (E+I). In front of the presented results, the soybean degumming oil added with emulsifier (OSDu) was chosen, which commercial product is the Natur’l Oil. The mentioned processes were evaluated by studies: carbon and nitrogen transformation by soil microorganisms, leaching and biodegradability in soils testing the following concentrations: DMA (700 g of endosulfan /ha - DMA) and DMA+O (700 g of endosulfan mixed with the 2L/ha of Natur’l Oil). The results showed that statistically there were not significant differences in the carbon and nitrogen transformations, such in the biodegradability test in the soil, when compared the treatments in presence and absent of the Natur’l Oil. The leaching results showed the following the endosulfan percents: 91.68 and 66.04 in the soil and 5.18 and 4.98 in the leached, for treatments DMA and DMA+O, respectively. The leached values were not statically different. However, for soil results observed that the presence of Natur’l Oil promotes a lower adsorption of endosulfan and higher dissipation. In fact the presence of Natur’l Oil did not affect the carbon and nitrogen transformation and biodegradability test of endosulfan in soil and in the leaching process, the presence of oil brought positives increments, disfavoring the pesticide percolation. The added of oils like adhesive dispersed should be considerate in pesticide application to reduce the leaching and for avoid the direct contact of pesticides with soil microorganisms, providing a higher lag phase and the biodiversity preservation.

Neste trabalho foi realizada a caracterização de um poliuretano derivado de óleo vegetal para ser utilizado na confecção de dispositivos de assistência ventricular, DAVs. Esses dispositivos são muito importantes na área cardiovascular, pois, possuem a função de suprir a falha dos ventrículos direitos ou esquerdo do coração durante o bombeamento em casos de transplante. Para que esse material seja apto para ser utilizado, precisa-se ter propriedades mecânicas, térmicas e biológicas compatíveis com as necessidades médicas da área cardiovascular. Neste estudo foram utilizadas as técnicas de ensaio mecânico de tração e compressão, as técnicas termoanalíticas DMA, TGA, DSC, bem como espectroscopia de absorção na região do infravermelho. Para os ensaios biológicos foram feitos os teste de tempo de coagulação sanguínea (método Lee White) e o estudo de crescimento celular acompanhado por análise de microscopia eletrônica de varredura (MEV). Os resultados obtidos nos ensaios mecânicos mostraram que o poliuretano possui propriedades que não comprometem sua utilização na confecção dos DAVs. Com relação às análises térmicas, os resultados obtidos pelas curvas DMA mostraram que o poliuretano aumenta seu grau de cura e sua rigidez com o tratamento térmico. As curvas TG e as TG/DSC-FTIR mostram que o poliuretano é termicamente estável e não libera nenhum tipo de substância prejudicial ao ser humano até a temperatura de 200°C, viabilizando uma condição de serviço satisfatória a temperatura corpórea entre 36ºC e 40°C. Os testes biológicos demonstraram que o poliuretano possui potencial para ser utilizado em dispositivos médicos que entram em contato com o sangue, tornando-se necessários estudos para a sua total comprovação de ser um material hemocompatível. / In this study the characterization of a polyurethane derived from vegetable oil was studied for the use in the production of ventricular assistance devices, VADs. These devices are very important in the cardiovascular area, therefore they have the function of supplying the failure of the right or left ventricles of the heart while pumping in transplants. For this material to be used in this application, it must have mechanical, thermal and biological properties compatible with the medical require of the cardiovascular area. In this study was to used the techniques of mechanical tensile and compressive, the thermoanalytical techniques such as DMA, TGA, DSC and absorption spectroscopy in the infrared region. The biological analysis were the test of blood coagulation time (Lee White method) and the study of cellular growth measured by scanning electron microscopy (SEM). The results obtained in the mechanical tests showed that the polyurethane has properties that do not compromise their use in the production of VADs. In relation the thermal analysis of the results obtained by DMA, the curves showed that the polyurethane increases its cure and rigity degrees with thermal treatment. The TG and TG/DSC-FTIR curves showed that the polyurethane is thermally stable does not release any prejudicial substances to the human body until the temperature of 200°C, enabling a satisfactory service condition to body temperature between 36 and 40°C. The biological tests showed that the polyurethane has the potential to be used in medical devices that come into contact with blood, however it\'s needing more studies for its full proof of being a hemocompatible material.

Quatro potros, filhos do mesmo pai, com idade média de 18 meses e peso aproximado de 270 kg, receberam dieta composta de feno de Coast-Cross (Cynodon dactylon L. Pers.) e concentrado experimental, ao qual foram adicionados diferentes tipos de óleo vegetal (soja, canola, palma ou linhaça), para analisar o efeito sobre a aceitabilidade, digestibilidade aparente da Matéria Seca (MS), Matéria Orgânica (MO), Proteína Bruta (PB), Extrato Etéreo (EE), Fibra Solúvel em Detergente Neutro (FDN), Fibra Solúvel em Detergente Ácido (FDA), valores plasmáticos de Colesterol, VLDL, LDL, HDL e Triglicérides. Foi utilizada metodologia de coleta total de fezes e coleta de sangue na veia jugular às 7 horas, em jejum. O delineamento experimental foi em Quadrado Latino (4 animais, 4 tratamentos, 4 repetições). A inclusão dos óleos não afetou significativamente (p<0,05) a aceitabilidade e a digestibilidade da MS, MO, PB, EE, FDN e FDA. Também não foram alterados (p<0,05) os valores plasmáticos de colesterol, LDL, VLDL, HDL e triglicérides, indicando que os óleos de soja, canola, palma e linhaça podem ser igualmente utilizados na dieta de eqüinos. / Four foals, same father sons, aged 18 months and average weight 320 kg, were fed a diet composed of Coast-cross hay (Cynodon dactylon L. Pers.) and concentrate, to analyze the effect of adding different types of vegetable oil (soybean, canola, palm and linseed) on acceptability, apparent digestibility of Dry Matter (DM), Crude Original Matter (CM), Crude Protein (CP), Ethereal Extract (EE), Neutral Detergent Soluble Fiber (NDF), Acid Detergent Soluble Fiber (ADF) and on cholesterol, VLDL, LDL, HDL and triglycerides plasma levels. Total fecal output collect methodology was used. Blood samples were collected at 7:00 a.m. during ingestion and cooled until sending to the laboratory. Experimental delineation was Latin Square (4 animals, 4 repetitions, 4 treatments). The inclusion of different vegetable oils in diet did not affect (p<0,05) acceptability nor DM, CM, CP, G, NDF and ADF digestibility. Cholesterol, VLDL, LDL, HDL and triglycerides plasma levels were not affected (p<0,05).

Problemas ambientais causados pelo uso excessivo de energia proveniente do petróleo estão fazendo com que os países busquem a diversificação da matriz energética. Dentro deste contexto, é que a produção de biodiesel, a partir de óleos vegetais, vem se destacando no cenário energético. A extração da matéria-prima usada na produção desses biocombustível é uma fase de extrema importância, por isso, faz-se necessário determinar qual a melhor forma de sua realização, caracterizando os principais fatores químicos e físicos que interferem nesse processo. Visando otimizar o processo de extração do óleo do caroço do pequi, este trabalho baseou-se na realização de experimentos que buscaram identificar o teor aproximado de óleo no caroço do pequi e ainda qual o melhor solvente orgânico, entre hexano, etanol e a mistura desses solventes, para a extração do óleo do caroço do pequi para a produção de biodiesel. A partir dos dados obtidos nos ensaios realizados neste trabalho, pode ser observado que o putâmem do pequi apresenta um teor elevado de óleo, em méidia de 31%, quantidade superior a encontrada no grão da soja, que hoje é a matéria – prima base para a produção de biodiesel. Observou-se ainda que a misturas dos dois solventes orgânicos (hexano + etanol) na razão de 1:1 mostrou-se mais eficiente no processo extraíndo aproximadamente 34% do óleo presente no caroço do pequi. / The environmental problems caused by the excessive use of energy from petroleum are causing countries seek to diversify sources of energy. Within this context, is that the production of biodiesel from vegetable oils, has been increasing in energy scenario. The extraction of the raw material used in producing these biofuels is an extremely important step, so it is necessary to determine the best form of his achievement, featuring the main chemical and physical factors that affect this process. In order to optimize the extraction process of oil pits pequi, this work was based on the realization of experiments that attempted to identify the approximate oil content in the pits pequi and yet which is the best organic solvent, hexane between ethanol and the mixture of these solvents for oil extraction from the seed pequi for biodiesel production. Starting from the data obtained in the tests performed in this study, it can be observed that the pits pequi has a high content of oil, around 31%, much higher than found in soy beans, which today is raw - material basis for biodiesel production. It was also observed that mixtures of two organic solvents (hexane + ethanol) at a ratio of 1:1 was more efficient in the process of Extracting approximately 34% of the oil present in the pits pequi.

Wong Yiu Kwong Kenji. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2005. / Includes bibliographical references (leaves 189-204). / Abstracts in English and Chinese. / Acknowledgement --- p.i / Abstract --- p.ii / 摘要 --- p.iv / Contents --- p.vi / List of Figure --- p.xii / List of Table --- p.xvi / Introduction --- p.1 / Chapter 1.1. --- Vegetable oil production and their refining --- p.1 / Chapter 1.1.1. --- Vegetable oil production and consumption --- p.1 / Chapter 1.1.2. --- Vegetable oil refining steps --- p.2 / Chapter 1.2. --- Chemical refining vs. Physical refining --- p.3 / Chapter 1.2.1. --- Differences between chemical and physical refining --- p.3 / Chapter 1.2.2. --- Pros and Cons of the two refining practices --- p.4 / Chapter 1.2.3. --- Adoption criteria and popularity of refining methods --- p.6 / Chapter 1.3. --- Deodorizer distillate (DODc vs. DODp) --- p.7 / Chapter 1.3.1. --- Compositions of DODc and DODp --- p.7 / Chapter 1.3.1.1. --- Squalene --- p.9 / Chapter 1.3.1.2. --- Tocopherols --- p.10 / Chapter 1.3.1.3. --- Phytosterols --- p.12 / Chapter 1.3.2. --- Usages of DODc and DODp and purification of phytochemicals --- p.14 / Chapter 1.3.2.1. --- Concentration of tocopherols and phytosterols --- p.15 / Chapter 1.3.2.2. --- Purification of tocopherols and phytosterols --- p.18 / Chapter 1.3.3. --- Alternative usage of DODp --- p.20 / Chapter 1.4. --- Usages of fatty acid mono-alkyl esters --- p.20 / Chapter 1.4.1. --- As intermediate for Bio-surfactants --- p.21 / Chapter 1.4.2. --- Bio-lubricants --- p.21 / Chapter 1.4.3. --- Biodiesel --- p.22 / Chapter 1.5. --- Production of biodiesel and its advantages and disadvantages --- p.23 / Chapter 1.5.1. --- Production of biodiesel --- p.23 / Chapter 1.5.1.1. --- Use of catalyst --- p.25 / Chapter 1.5.1.2. --- "Molar ratios between methanol, sample and catalyst" --- p.26 / Chapter 1.5.1.3. --- Temperature and pressure --- p.27 / Chapter 1.5.1.4. --- Biodiesel purification --- p.27 / Chapter 1.5.2. --- Pros and Cons of using biodiesel --- p.27 / Chapter 1.5.3. --- Sources of Biodiesel production --- p.29 / Chapter 1.6. --- Proposed strategy --- p.33 / Chapter 1.6.1. --- Summary of the literatures reviewed --- p.33 / Chapter 1.6.2. --- Hypothesis making --- p.34 / Chapter 1.6.3. --- Aim and objectives --- p.34 / Chapter 1.6.4. --- Significance of study --- p.34 / Chapter 1.6.5. --- Study scheme --- p.35 / Chapter 2. --- Methodology --- p.36 / Chapter 2.1. --- Characterization of physically refined Deodorizer Distillate (DODp) --- p.36 / Chapter 2.1.1. --- Collection & storage of DODp --- p.36 / Chapter 2.1.2. --- Determination of fatty acids composition --- p.36 / Chapter 2.1.3. --- Determination of acid number (ASTM D 664) --- p.37 / Chapter 2.1.4. --- Determination of free fatty acid contents --- p.38 / Chapter 2.1.5. --- Determination of unsaponifiable matter content --- p.38 / Chapter 2.1.6. --- "Determination of squalene, tocopherol and phytosterol contents." --- p.39 / Chapter 2.1.7. --- Deduction of natural glyceride contents --- p.40 / Chapter 2.1.8. --- "Other physical, chemical and biological analyses" --- p.40 / Chapter 2.1.8.1. --- Elemental analysis --- p.40 / Chapter 2.1.8.2. --- Nitrogen --- p.41 / Chapter 2.1.8.3. --- Water and volatile matter content --- p.41 / Chapter 2.1.8.4. --- Melting point and specific gravity --- p.41 / Chapter 2.1.8.5. --- Microbial counts --- p.42 / Chapter 2.2. --- Production of fatty acid methyl esters (FAMEs) - Protocol A --- p.42 / Chapter 2.2.1. --- Optimization of Esterification --- p.42 / Chapter 2.2.1.1. --- Molar ratio of methanol: DODp --- p.43 / Chapter 2.2.1.2. --- Molar ratio of DODp: sulfuric acid --- p.43 / Chapter 2.2.1.3. --- Reaction temperature --- p.44 / Chapter 2.2.2. --- Optimization of Molecular Distillation --- p.44 / Chapter 2.2.2.1. --- Feed rate --- p.45 / Chapter 2.2.2.2. --- Distillation temperature --- p.45 / Chapter 2.2.2.3. --- Speed of rotary blade --- p.45 / Chapter 2.2.3. --- Crystallization --- p.46 / Chapter 2.3. --- Production of fatty acid methyl esters (FAMEs) - Protocol B --- p.46 / Chapter 2.3.1. --- Optimization of Saponification --- p.47 / Chapter 2.3.1.1. --- Saponification number --- p.47 / Chapter 2.3.1.2. --- Saponification --- p.47 / Chapter 2.3.2. --- Extraction of unsaponifiable matter --- p.48 / Chapter 2.3.3. --- Acidification --- p.49 / Chapter 2.3.4. --- Esterification --- p.49 / Chapter 2.3.5. --- Hot water washing --- p.49 / Chapter 2.3.6. --- Crystallization --- p.49 / Chapter 2.4. --- Quantity and quality assessments of FAMEs --- p.50 / Chapter 2.4.1. --- Determination of purity and yield of FAMEs --- p.50 / Chapter 2.4.2. --- Quality of FAMEs: Biodiesel Specifications in USA --- p.50 / Chapter 2.4.2.1. --- Sulfated Ash (ASTM D 874) --- p.50 / Chapter 2.4.2.2. --- Copper strip corrosion test (ASTM D 130) --- p.51 / Chapter 2.4.2.3. --- Water and Sediment (ASTM D 2709) --- p.52 / Chapter 2.4.2.4. --- Conradson Carbon Residue of Petroleum Products (ASTM D 189) --- p.52 / Chapter 2.4.2.5. --- Determination of Free and Total Glycerine in B-100 Biodiesel Methyl Esters By Gas Chromatography (ASTM D 6584) --- p.53 / Chapter 2.4.2.6. --- Flash point (modified from ASTM D 93) --- p.54 / Chapter 2.4.2.7. --- Determination of Additive Elements in Lubricating Oils by Inductively Coupled Plasma Atomic Emission Spectrometry (ASTM D 4951) --- p.54 / Chapter 2.4.2.8. --- Kinematic Viscosity --- p.55 / Chapter 2.4.2.9. --- "Cetane index, Cloud Point and Distillation Temperature (ASTM D 613, ASTM D 2500 and ASTM D 90)" --- p.55 / Chapter 2.4.3. --- Toxicity assays of FAMEs --- p.55 / Chapter 2.4.3.1. --- Acute toxicity to mice --- p.56 / Chapter 2.4.3.2. --- Seed germination test --- p.56 / Chapter 2.4.3.3. --- Acute toxicity to aquatic invertebrate --- p.56 / Chapter 2.5. --- Quantity and quality assessments of phytochemical products --- p.57 / Chapter 2.5.1. --- Determination of purity and yield of phytochemicals in phytosterol and desterolized fractions --- p.57 / Chapter 2.5.2. --- Antioxidants activity of desterolized fraction --- p.58 / Chapter 2.5.2.1. --- ABTS scavenging activity --- p.58 / Chapter 2.5.2.2. --- Free radical scavenging activity --- p.58 / Chapter 2.5.3. --- Anti-proliferative effect on cancer cells of phytosterols --- p.59 / Chapter 2.5.3.1. --- Cell culture --- p.59 / Chapter 2.5.3.2. --- Determination of optimal cell density for antiproliferative assays --- p.59 / Chapter 2.5.3.3. --- Anti-proliferative effect of phytosterols on H1299 and Hep G2. --- p.60 / Chapter 2.5.3.4. --- Detection of action mechanism(s) of the anti-proliferative effects of β-sitosterol on H1299 and Hep G2 cancer cells --- p.61 / Chapter 3. --- Result --- p.70 / Chapter 3.1. --- Characterization of Physically Refined Deodorizer Distillate (DODp) --- p.70 / Chapter 3.1.1. --- Free fatty acids composition --- p.70 / Chapter 3.1.2. --- Acid number --- p.75 / Chapter 3.1.3. --- "Free fatty acids, natural glyceride and unsaponifiable matter contents" --- p.75 / Chapter 3.1.4. --- "Squalene, tocopherol and phytosterol contents" --- p.77 / Chapter 3.1.5. --- Other physicochemical and biological analyses --- p.81 / Chapter 3.2. --- Production of fatty acid methyl esters (FAMEs) - Protocol A --- p.83 / Chapter 3.2.1. --- Optimization of Esterification --- p.83 / Chapter 3.2.1.1. --- Methanol to DODp molar ratio --- p.83 / Chapter 3.2.1.2. --- DODp to sulfuric acid molar ratio --- p.85 / Chapter 3.2.1.3. --- Reaction temperature --- p.87 / Chapter 3.2.1.4. --- Calculation of esterification efficiency --- p.87 / Chapter 3.2.2. --- Optimization of Molecular Distillation --- p.89 / Chapter 3.2.2.1. --- Feed rate --- p.89 / Chapter 3.2.2.2. --- Distillation temperature --- p.91 / Chapter 3.2.2.3. --- Rotating blade speed --- p.93 / Chapter 3.2.3. --- Crystallization --- p.97 / Chapter 3.2.3.1. --- Phytosterol preparations --- p.97 / Chapter 3.2.3.2. --- Desterolized fractions --- p.97 / Chapter 3.3. --- Production of fatty acid methyl esters (FAMEs) 一 Protocol B --- p.99 / Chapter 3.3.1. --- Optimization of Saponification --- p.99 / Chapter 3.3.1.1. --- Saponification number --- p.99 / Chapter 3.3.1.2. --- Saponification --- p.99 / Chapter 3.3.2. --- Extraction of unsaponifiable matter --- p.101 / Chapter 3.3.3. --- FAMEs product after esterification --- p.101 / Chapter 3.3.4. --- Crystallization --- p.104 / Chapter 3.3.4.1. --- Phytosterol preparations --- p.104 / Chapter 3.3.4.2. --- Desterolized fractions --- p.104 / Chapter 3.4. --- Quantity and Quality assessments of FAMEs --- p.106 / Chapter 3.4.1. --- "FAMEs yield, purity and appearance" --- p.106 / Chapter 3.4.2. --- Specifications for Biodiesel in U.S.A --- p.106 / Chapter 3.4.3. --- Acute Toxicity assays of FAMEs --- p.109 / Chapter 3.4.3.1. --- Acute toxicity to mice --- p.109 / Chapter 3.4.3.2. --- Seed germination test --- p.109 / Chapter 3.4.3.3. --- Acute toxicity to aquatic invertebrate --- p.109 / Chapter 3.5. --- Quantity and Quality assessments of phytochemicals --- p.113 / Chapter 3.5.1. --- Phytochemicals recoveries and compositions in phytosterol preparations and desterolized fractions --- p.113 / Chapter 3.5.1.1. --- Phytosterols recoveries and compositions in phytosterol preparations --- p.113 / Chapter 3.5.1.2. --- Squalene and tocopherols recoveries and compositions in desterolized fraction --- p.115 / Chapter 3.5.2. --- Antioxidant activities of desterolized fractions --- p.118 / Chapter 3.5.2.1. --- ABTS scavenging activity --- p.118 / Chapter 3.5.2.2. --- Scavenging Activities of DPPH radicals --- p.120 / Chapter 3.5.3. --- Anti-proliferative effect of phytosterols on cancer cells --- p.123 / Chapter 3.5.3.1. --- Determination of optimal cell density for antiproliferative assays --- p.123 / Chapter 3.5.3.2. --- Anti-proliferative effect of phytosterols on H1299 --- p.126 / Chapter 3.5.3.3. --- Anti-proliferative effect of phytosterols on Hep G2 --- p.132 / Chapter 3.5.3.4. --- Further investigation of anti-proliferative mechanism of β-sitosterol --- p.138 / Chapter 4. --- Discussion --- p.149 / Chapter 4.1. --- Characteristics of Physically Refined Deodorizer Distillate (DODp) --- p.149 / Chapter 4.1.1. --- Fatty acid contents and compositions --- p.149 / Chapter 4.1.2. --- "Squalene, tocopherol and phytosterol contents" --- p.153 / Chapter 4.1.3. --- Other physical and chemical analyses --- p.155 / Chapter 4.2. --- Production of fatty acid methyl esters (FAMEs) 一 Protocol A --- p.156 / Chapter 4.2.1. --- Optimization of Esterification --- p.156 / Chapter 4.2.2. --- Optimization of Molecular Distillation --- p.158 / Chapter 4.3. --- Production of fatty acid methyl esters (FAMEs) 一 Protocol B --- p.159 / Chapter 4.3.1. --- Optimization of Saponification --- p.159 / Chapter 4.3.2. --- Extraction of unsaponifiable matter --- p.160 / Chapter 4.3.3. --- Production of FAMEs --- p.161 / Chapter 4.4. --- Purification of phytosterols --- p.162 / Chapter 4.4.1. --- Purity and recovery of phytosterols --- p.162 / Chapter 4.4.2. --- Purity and recovery of squalene and tocopherols in desterolized fractions --- p.163 / Chapter 4.5. --- Quantification of the Loss of Valuable products during Processing --- p.165 / Chapter 4.6. --- Quality assessment of FAMEs and phytochemicals --- p.170 / Chapter 4.6.1. --- Specifications for Biodiesel in USA --- p.170 / Chapter 4.6.2. --- Acute toxicities of FAMEs --- p.171 / Chapter 4.6.3. --- Antioxidant activities of desterolized fractions --- p.172 / Chapter 4.6.4. --- Anti-proliferative effects of phytosterols on cancer cells --- p.173 / Chapter 4.7. --- Comparisons of the two protocols --- p.182 / Chapter 4.7.1. --- Products from protocol A and B --- p.182 / Chapter 4.7.2. --- Characteristics of protocol A and B --- p.183 / Chapter 4.7.3. --- Sustainable recycling technology --- p.184 / Chapter 4.7.4. --- Life cycle analysis --- p.185 / Chapter 4.8. --- Further investigation --- p.186 / Chapter 5. --- Conclusion --- p.187 / Chapter 6. --- Reference --- p.189