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Studium reologických vlastností alternativních elektroizolačních kapalin / Study of rheological properties of alternative electro insulating fluidsBotlová, Simona January 2016 (has links)
This master thesis deals with clasification of electrical insulating liquids and analysis their reological properties. Theoretical part describes viscosity and possibilities of its measurement, electrical and non-electricl properties of electrical insulating liquids and themselves electrical insulating liquids. Practical part describes measurement of viscosity and density of chosen vegetable oils, their components and transformer oils in wide temperature range. At the conclusion of the thesis, analysis of measurement results is done.
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The evaluation of the nutritive value of Baobab seed cake and Macadamia oil cake as feed for ruminantsMikasi, Masiza Samuel 21 September 2018 (has links)
PhD (AGR) (Animal Science) / Department of Animal Science / Horticultural by-products such as seed and nut oil residues have the potential to replace
conventional protein and energy sources in diets for ruminants.
The objective of the study was to evaluate the nutritive value of Macadamia oil cake and
Baobab seed cake as nutrient supplements for feedlot animals. Several experiments were
carried-out to evaluate the nutritive value of Macadamia oil cake and Baobab seed cake as feed
for ruminants. The nutrient composition of the cakes were determined using both proximate and
modern methods of analysis of feeds and a t-test was used to compare the means of
Macadamia oil cake and Baobab seed cake. The in sacco technique was used to determine the
rumen degradability parameters of dry matter, crude protein and Amino acids of the cakes. This
experiment was conducted using a completely randomized design. A three step-in vitro
technique was used to conduct a post ruminal digestibility trial and the study was arranged in a
completely randomized design. An apparent digestibility trial was conducted using metabolism
cages and fecal bags to avoid the mixing of urine and faeces and the experiment was carried
out as a completely randomized design arranged in a 2 x 2 factorial. A growth trial was
conducted using a completely randomized block design arranged in a 2x2 factorial with two
protein supplements and two inclusion levels as factors and blocked by sex of the lambs.
The two cakes had similar (P>0.05) dry matter, fat, hemicellulose and gross energy contents.
Baobab seed cake had significantly (P<0.05) higher ash, crude protein, acid detergent lignin
and nitrogen free extract than macadamia oil cake. Macadamia oil cake had significantly
(P<0.05) higher crude fiber, acid detergent fiber, neutral detergent fiber and cellulose
concentrations. Baobab seed cake had significantly (P<0.05) higher calcium, magnesium,
potassium, phosphorus (macroelements), zinc, and copper than macadamia oil cake.
Macadamia oil cake was significantly (P<0.05) higher in manganese and iron contents than
Baobab seed cake. Sodium content was not significantly (P>0.05) different between the two
cakes. Baobab seed cake had more (Tryptophan, Cysteine, Arginine, Aspartic acid, Glutamic
acid, Valine, Phenylalanine, Isoleucine, Leucine) Amino acids which were significantly (P<0.05)
higher in quantity than macadamia oil cake with the two cakes having similar (P>0.05)
remaining Amino acids contents. Generally Macadamia oil cake had more (P<0.05) saturated
and mono-unsaturated fatty acids than Baobab seed cake whereas Baobab seed cake had
more (P<0.05) poly-unsaturated fatty acids.
v
The in sacco rumen degradability characteristics of baobab seed cake and macadamia oil cake
were estimated for dry matter and crude protein of the cakes. Macadamia oil cake had
significantly (P<0.01) higher a value for dry matter than boabab seed cake. Baoaba seed cake
had significantly (P<0.01) higher a value for crude protein than macadamia oil cake. the b, c,
and a+b values for dry matter of both Baobab seed cake and Macadamia oil cake were not
significantly (P>0.05) different form each other. However, the potential degradability (a+b) value
for crude protein of baobab seed cake was significantly (P<0.01) higher than that of macadamia
oil cake. The b and c constants of the two cakes for crude protein were not significantly
(P>0.05) different from each other. The ED (Effective degradability) values calculated at three
outflow rates (0.02, 0.05, 0.08) were estimated for dry matter and crude protein of Baobab seed
cake and macadamia oil cake. The ED of the two cakes calculated at 0.02 outflow rate did not
significantly (P>0.05) differ from each other. However, baobab seed cake had significantly
(P<0.05) higher ED value at outflow rate of 0.05 whereas macadamia oil cake had significantly
(P<0.05) higher ED value calculated at outflow rate of 0.08. The ED values of baobab seed
cake for crude protein calculated at the three outflow rate were significantly (P<0.01) higher
than those of macadamia oil cake. The two cakes did not significantly (P>0.05) differ in dry
matter ruminal degradability but baobab seed cake had significantly (P<0.05) higher ruminal
crude protein disappearance from 16 to 72 hours of incubation than macadamia oil cake. The in
situ Amino acid degradation was determined on 0, 12, 16, 24, and 48 hour of ruminal incubation
of the cakes’ samples and generally they were significant (P<0.05) differences for both cakes
according to different incubation periods. The 3-step in vitro digestibility trial revealed that
baobab seed cake had significantly (P<0.05) higher dry matter, crude protein and Amino acids
digestibility values than macadamia oil cake. Apparent digestibility study revealed that nutrient
intake, faecal and urine outputs, and digestibility of nutrients were not significantly (P>0.05)
different between baobab seed cake and macadamia oil cake. However, lambs on 10%
macadamia cake having retained significantly (P<0.05) more nitrogen than the lambs on 15%
macadamia oil cake, 10% and 15% baobab seed cakes diets. However, the inclusion of either
baobab seed cake or macadamia oil cake at 10% or 15% in the diets of lambs did not
significantly (P>0.05) affect the DOMR, microbial protein yield and purine derivates output.
For the growth trial the lambs were offered four diets formulated to contain 10% MOC (control),
15% MOC, 10 BSC and 15% BSC. The inclusion of 15% MOC and 10% BSC in the diets of
lambs did not significantly (P>0.05) affect their final body weight, total weight gain, average
daily feed intake, average daily weight gain, warm and cold carcass masses between these two
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groups. The inclusion of 10% MOC and 15% BSC in the diets of lambs did not significantly
affect average daily feed intake and animal performance between these two groups. However,
lambs on 10% MOC and 15% BSC had significantly (P<0.05) higher average daily feed intake
and animal performance compared to lambs on 15% MOC diet. The feed conversion efficiency
and of the lambs in the four diets were not significantly (P>0.05) different. The dressing
percentage, carcass length, neck weight, fat thickness, body weight thickness and rib eye area
of the carcasses of lambs in this trial did not differ significantly (P>0.05) except for spleen and
skin with lambs on 10% BSC diets having the least skin weight and lambs on 10% MOC diet
having heaver spleens.
Generally BSC had higher (P<0.05) nutrient content than MOC. BSC and MOC were highly
degradable in the rumen whereas BSC was higly digestible post-ruminally compared to MOC.
The diets of fattening lambs formulated to include 10% or 15% of BSC or MOC as protein
supplements did not affect the apparent digestibility of the diets. Macadamia oil cake can be
incomporated in the diet of finishing lambs as a protein supplement at 10% inclusion level
without compromising the growth and carcass characteristics of the lambs. Baobab seed cake
as a protein supplement can be included in the diet of finishing lambs at up to 15% inclusion
level without deleteriously compromising on the growth and carcass characteristics of the
animals.
______________________________________ / NRF
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Élaboration de plastifiants ignifugeants à base de dérivés lipidiques pour formulations PVC / Elaboration of lipidic flame retardant plasticizers for PVCBocqué, Maëva 25 November 2015 (has links)
E PVC est l'un des polymères les plus employés dans les matériaux actuels et l'adjonction de plastifiants permet de modifier ses propriétés (température de transition vitreuse, module…) permettant ainsi l'utilisation de ce polymères dans des applications où de la souplesse est requise (textiles enduits, par exemple). Actuellement, les phtalates sont les plastifiants les plus utilisés même s'ils sont de plus en plus décriés du fait de leur toxicité. Le développement de nouveaux agents plastifiants est un domaine de recherches intenses et les matières premières bio-sourcées s'avèrent être une alternative intéressante aux plastifiants pétro-sourcés. Le travail de cette thèse se propose d'investiguer le développement de plastifiants du PVC bio-sourcés de type lipidique possédant de surcroit des propriétés ignifugeantes évitant ainsi l'ajout d'additifs supplémentaires dans les formulations de PVC devant résister au feu. Dans un premier temps, l'oléate, le linoléate de méthyle et le diacide (D18 : 1) ont été fonctionnalisés par modification chimique de leurs groupements ester et/ou de leurs insaturations pour mener à des dérivés lipidiques phosphorés. Cinq candidats plastifiants bio-sourcés ont ainsi pu être synthétisés et le scale up de la synthèse de l'un des candidats à l'échelle du kilogramme a pu être réalisé dans le cadre de cette thèse. Dans un deuxième temps, des tests de plastification du PVC avec divers candidats ont été réalisés en collaboration avec la société Serge FERRARI. L'étude des propriétés thermiques, mécaniques et thermomécaniques des films de PVC plastifiés obtenus, comparativement au plastifiant phtalate DINP et au plastifiant bio-sourcé commercial RADIA 7295, a permis d'éliminer différents candidats pour n'en finalement retenir que deux. Des profils de dégradation thermique satisfaisants, des basses valeurs de Tg, des allongements à la rupture importants (320 et 365 % respectivement) et proches de ceux obtenus avec le DINP, ont confirmé l'efficacité plastifiante de ces deux composés phosphorés bio-sourcés. Les tests au feu LOI et au cône calorimètre ont également prouvé le caractère ignifugeant de ces deux composés qui conduisent à des résultats du même ordre de grandeur que ceux atteints avec le plastifiant phosphonate commercial de référence S141 / Poly(vinyl chloride) is one of the most manufactured and consumed thermoplastics in the world. The addition of plasticizers allows modifying its properties (glass transition temperature, modulus…) and then to use this polymer for applications where flexibility is needed (coated textiles, for instance). Nowadays, phthalates are the main candidates for PVC even if they have been more and more controversed due to their possible toxicity. To substitute these petro-based plasticizers, researches are focused on alternative plasticizers based on bio-based raw materials. This PhD work proposes to investigate the development of new bio-based plasticizers for PVC, from lipidic derivatives, and having simultaneously flame retardant properties, avoiding the addition of any other additives in PVC during compounding. In the first part, methyl oleate, methyl linoleate and diacid D18 : 1 have been functionalized by modification of their ester groups and/or their doubles bonds to give phosphorylated lipidic derivatives. Thus, five bio-based plasticizers have been synthesized and the synthesis of one candidate on the scale of the kilogram has been successfully performed during this PhD work. Secondly, the plasticizing efficiency of several candidates with PVC has been evaluated in collaboration an industrial company. Thermal, mechanical and thermomechanical properties of the obtained soft PVC films were studied, in comparison with those obtained with the phthalate plasticizer DINP and the commercial bio-based plasticizer RADIA 7295. These analyses allowed the disposal of some of the bio-based plasticizers to finally keep only two candidates. Satisfying thermal degradation profiles, low Tg, and important elongation at break values (320 % and 365 % respectively) close to those obtained with DINP, confirmed the plasticizing efficiency of these two bio-based phosphorylated plasticizers. Fire tests like the LOI test and the cone calorimeter also proved the flame retardant properties of these two candidates, leading to similar results than the ones reached with the phosphonate plasticizer S141
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Hodnocení stability vybraných rostlinných olejů / Evaluation of stability of selected vegetable oilsNěmečková, Lenka January 2010 (has links)
This diploma thesis is focused on issues concerning the stability of selected vegetable oils which are used in cosmetic industry. The stability of eight oils without additives were determined by a differential scanning calorimeter. In the first phase, the temperatures of oil degradation were determined for different rates of heating, i.e. nonisothermal stabilities. They were consequetly used to calculate isothermal stabilities alias induction periods. The calculation of induction periods was completed by using integral isoconversional methods, which applied four different temperature functions. One of the temperature functions corresponded to Arrhenius equation while the others to non-Arrhenius functions. The confrontation of induction periods under standart conditions showed that an optimal temperature function to calculate oil stabilities is one of the non-Arrhenius functions in exponential form. We can state that all oils are degraded by similar, if not the same, mechanism. The specified stabilities, in periods of months, have proved the importance of using stabilizers and other additives in the commercial and technological use of vegetable oils.
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<b>Synthesis and characterization of soybean oil derivatives for metalworking lubricants and gear oils</b>Elena A Robles Molina (9751112) 02 August 2024 (has links)
<p dir="ltr">Vegetable oils are a fundamental part of human civilization. Beyond their nutritional value and functional implementation in food applications, their triglyceride structure facilitates their implementation as industrial inputs. Furthermore, applications such as metal gear fluids and gear oil represent a valuable market due to their environmental impact and widespread application. Soybean oil is one of the most produced oilseeds in the U.S., and recently, novel oil varieties such as high oleic soybean oil (HOSBO) tackle drawbacks in the use of vegetable oil such as the heterogeneous fatty acid composition by increasing the concentration of oleic acid. This dissertation evaluates the successful implementation of HOSBO and SBO as lubricant and gear oils through epoxy ring opening reactions for synthesizing polyols and estolides. Epoxidation of double bonds in unsaturated fatty acids creates reaction sites for the branching of fatty acids in estolides or hydroxylated moieties in the case of polyols. The difference in fatty acid composition is shown in terms of thermomechanical characteristics. HOSBO polyols and estolides are solid to semi-solid greases with high viscosities and SAE grades as gear oils from 85W up. In contrast, SBO-derived oils have lower viscosities and a larger viscosity index.</p><p dir="ltr">The second part of this research focuses on the kinetics of the hydroxylation defined by distinctive fatty acid compositions. The sites of reaction in the double bonds can be, in part, sterically hindered by the glycerol backbone. Thus, this chapter focuses on the influence of the reaction rates given the fatty acid composition of the oil. Consumption of epoxide groups in HOSBO and SBO was modeled under pseudo-first-order kinetics. The results highlight the benefit of using HOSBO with reaction rates at least 30% faster than SBO. Furthermore, the progress of the reaction was monitored by FTIR, which highlighted the formation of ether groups corresponding to the addition of 1-propanol branches. However, further optimization steps must focus on the controlled removal of water in order to prevent the esterification of the oil and the resulting increase of free fatty <a href="" target="_blank">acids</a><a href="#_msocom_1" target="_blank">[EAS1]</a> .</p><p dir="ltr"><a href="#_msoanchor_1" target="_blank">[EAS1]</a>Seems to end abruptly</p><p><br></p>
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Local resilience, canola cropping, and biodiesel productionBates, Christopher Allen 27 January 2006 (has links)
New technology may have negative, as well as positive, effects on a sociocultural
system. Biodiesel is growing in popularity as a fuel alternative that addresses global
warming and reduces dependency on petroleum. The biodiesel innovation fits well
into the existing behavioral infrastructure of Linn and Benton Counties, Oregon. The
introduction of this technology fuels two community-based biodiesel initiatives: the
Corvallis Biodiesel Cooperative (CBC) and the OSU Biodiesel Initiative (OBI).
However, the increasing demands for biodiesel increases the demand for vegetable oil.
Canola is the most efficient oil producing crop suggested for the southern Willamette
Valley of Oregon. Canola cropping fits into the behavioral infrastructure of local
grass seed growers' tradition. However, canola cropping presents outcrossing risks to
neighboring specialty seed and organic growers. This calls into question the resilience
and sustainability of canola cropping. The decisions made about biodiesel production
and oilseed cropping will impact the future environment, culture, political autonomy,
and sustainability of this local community. The dominant values that serve this community will determine the resilience of culture and identity that is maintained or
emerges in the face of social-ecological challenges and technological innovations.
The research methodology includes interviews, participant observation, and
informational media to triangulate data. These methods serve to inform an integrated
framework of holistic, values analysis, social-ecological, and cultural materialism
theoretical approaches. The holistic approach provides the behavioral components and
the values analysis approach provides the mental components that are integrated into a
cultural materialism framework. These components are evaluated by the social-ecological
approach. Evaluation of the CBC and OBI suggests that values play a
greater role in cultural materialism than previously believed. A new theoretical
perspective emerges to explain resilience and causal effects. The social-ecological
approach, illustrated by panarchy theory, is also integrated into the cultural
materialism approach. The integration of the four theoretical approaches, and the
emergence of a new theoretical perspective, provides a means to explain resilience and
sustainability for the CBC and OBI. This integrated approach also examines three
potential paths of resilience and sustainability for the grass seed, specialty seed, and
organic growing traditions.
Path A predicts long-term resilience and sustainability for grass seed growers and
canola cropping, but collapse for the specialty seed and organic growing traditions.
Path B predicts that a proposed regulated canola cropping compromise will only
prolong the inevitable collapse of the specialty seed and organic growing traditions.
Along both Paths A and B, diversity is lost from the sociocultural system as specialty
seed and organic growing traditions decline. Canola cropping increases the potential
for energy security, but food security is reduced. Path C suggests how to maintain the
current sociocultural system of grass seed, specialty seed, and organic growing
traditions and promote long-term resilience and sustainability. / Graduation date: 2006
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Estudo da produção de biodiesel a partir de óleo de babaçu e etanol utilizando a transesterificação alcalina tradicional com agitação mecânica e assistida por ultrassons / Evaluation of biodiesel production from babassu and ethanol applying traditional alkaline transesterification with mechanical stirring and under ultrasonic technologyPaiva, Eduardo José Mendes de 27 August 2010 (has links)
Neste trabalho foram sintetizados ésteres etílicos do óleo de babaçu através da catálise alcalina em meio homogêneo. O planejamento de experimentos foi utilizado como ferramenta de otimização e também na identificação dos principais fatores que influenciam nas conversões em ésteres etílicos. As reações de transesterificação foram realizadas através de duas metodologias de processo - a tradicional com agitação mecânica e a promovida por ondas ultrassônicas. A espectrometria de ressonância magnética nuclear foi utilizada na quantificação das conversões de todos os experimentos e a análise termogravimétrica foi empregada na determinação da pureza dos ésteres etílicos e do principal subproduto da reação - o glicerol. Matrizes ortogonais de Taguchi foram utilizadas para o desenvolvimento deste estudo. Os fatores independentes avaliados na transesterificação tradicional foram: razão molar etanol/óleo, temperatura, turbulência, razão ponderal catalisador/óleo, tempo e os tipos de catalisadores mais comumente empregados (NaOH e KOH). Os ensaios envolvendo a transesterificação clássica foram realizados sob atmosfera de nitrogênio e também sob atmosfera normal. Com o método sonoquímico foram avaliados os fatores: razão molar, tempo, razão ponderal catalisador/óleo e tipo de catalisador. O delineamento experimental mostrou que o principal fator a influenciar nas conversões em ésteres etílicos com ambos os métodos é a razão molar. Destaca-se ainda na transesterificação alcalina tradicional, a influência das interações entre a temperatura e o tempo, mostrando que melhores conversões são obtidas com temperaturas próximas a ambiente (27 a 30ºC). De acordo com o modelo obtido através do delineamento experimental, conversões superiores a 99% são obtidas quando a razão estequiométrica é ajustada em 6:1, utilizando-se 1,0% de KOH, sob agitação mecânica a 400rpm durante 60min. A influência da atmosfera de nitrogênio mostrou-se pouco significativa para a reação e conversões semelhantes foram obtidas com atmosfera normal. A transesterificação alcalina assistida por ondas ultrassônicas apresentou os melhores resultados em relação ao tempo de reação e de separação entre as fases glicerínica e de ésteres etílicos. O modelo experimental mostrou que conversões superiores a 99% podem ser obtidas em 10 minutos ajustando as variáveis independentes nos seguintes valores: razão estequiométrica em 6:1 com 1,0% de KOH. Em ambos os métodos o catalisador KOH mostrou-se superior ao NaOH, especialmente durante as etapas de purificação. A estratégia de purificação dos ésteres etílicos adotada consistiu na utilização de um solvente (hexano) e lavagens com HCl 0,1 mol.L-1 que foi otimizada para 12,5% de solução em relação ao peso de ésteres obtidos, coletados logo após a separação de fases. O rendimento mássico obtido com o modelo experimental, após procedimentos de lavagens mencionados, foi de 94,59%. O trabalho demonstrou que o processo de obtenção de biodiesel de babaçu apresenta ótimos rendimentos desde que os parâmetros de reação sejam otimizados. A sonoquímica mostrou-se potencialmente promissora para obtenção de elevadas conversões em curtos intervalos de tempo. / In this work ethyl esters of babassu oil were synthesized by alkaline catalysis in homogeneous medium. The experimental design was used as a tool for optimization of the transesterification reaction and also in identifying key factors influencing the conversion into ethyl esters. The transesterification reactions were performed using two methods of process - the traditional mechanical agitation and agitation promoted by sound waves. The nuclear magnetic resonance spectroscopy was used to quantify the conversion of all reactions of transesterification and thermogravimetric analysis was used to determine the purity of ethyl esters and the main byproduct of the reaction - the glycerol. Taguchi orthogonal arrays were used to develop this study. The independent factors evaluated in the transesterification traditional were: molar ratio ethanol / oil, temperature, stirring speed, weight ratio catalyst / oil, time and the types of most commonly used catalysts (NaOH and KOH). The classical experiments involving the transesterification were performed under nitrogen atmosphere and also under normal atmosphere. With the sonochemical method were evaluated the following factors: molar ratio, time, weight ratio catalyst / oil and type of catalyst. The experiment showed that the main factor influencing the conversion into ethyl esters in both methods is the molar ratio. The best conversion results were obtained with twice the stoichiometric quantity. Also noteworthy in the traditional alkaline transesterification is the influence of interactions between temperature and time, showing that the best conversions are obtained with temperatures close to ambient (30°C) in 60 minutes. According to the model obtained by the experimental design, conversions above 99% are obtained when the stoichiometric ratio is set at 6:1, with 1.0% KOH, under stirring at 400 rpm. The influence of nitrogen atmosphere was less significant for the reaction and similar conversions were obtained with normal atmosphere. Alkaline transesterification assisted by sound waves produced the best results with respect to time of reaction and phase separation of glycerin and ethyl esters. The experimental model showed that conversions above 99% can be obtained in 10 minutes by adjusting the independent variables in the following values: in the stoichiometric ratio 6:1 with 1.0% KOH. In both methods the KOH catalyst was superior to NaOH, influence also noted during the purification steps. Experimentally it was found that the formation of emulsions and gels are more frequent with the use of the sodium hydroxide catalyst. The strategy for purification of ethyl esters adopted was the use of a solvent (hexane) and washing with HCl 0.1 mol.L- 1 that was optimized for 12.5% solution by weight of esters obtained, collected just after phase separation. The mass yield obtained with the experimental model, after washing procedures mentioned, was 94.59%. The study showed that the process of obtaining babassu biodiesel has good yields since the reaction parameters are optimized. The sonochemical proved to be potentially promising for achieving high yields in short time, which might be an excellent route for production aiming to meet the high market demands.
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AvaliaÃÃo do desempenho e qualidade dos ovos de poedeiras comerciais, submetidas as dietas suplementadas com diferentes Ãleos vegetais / Evaluation of the performance and quality of eggs of commercial laying hens, submitted to the diets supplemented with different vegetal oilsMaria do Socorro Vieira dos Santos 11 April 2005 (has links)
A pesquisa foi desenvolvida no Setor de Avicultura do Departamento de Zootecnia do Centro de CiÃncias AgrÃrias da Universidade Federal do Cearà (UFC), objetivando avaliar o desempenho zootÃcnico e a qualidade dos ovos de poedeiras comerciais, submetidas Ãs dietas com diferentes Ãleos vegetais. O procedimento experimental envolveu 224 poedeiras comerciais da linhagem Hy-line W-36, com 23 semanas de idade, dividido em 5 ciclos de 28 dias, durante os quais foram coletados dados para estudo. O delineamento estatÃstico foi em blocos ao acaso, com 7 tratamentos, sendo a unidade experimental representada por 1 parcela com 8 aves, e 4 repetiÃÃes por tratamento. Os tratamentos constaram de 7 raÃÃes, com nÃvel de energia de 2.850 Kcal EM/kg e proteÃna de 18%, sendo: T1 - dieta basal (sem Ãleo); T2 - dieta basal + 2% de Ãleo de soja; T3 - dieta basal + 4% de Ãleo de soja; T4 - dieta basal + 2% de Ãleo de linhaÃa; T5 - dieta basal + 4% de Ãleo de linhaÃa; T6 - dieta basal + 2% de Ãleo de algodÃo e T7 - dieta basal + 4% Ãleo de algodÃo. A inclusÃo do Ãleo vegetal nas dietas nÃo possibilitou uma melhora absoluta (P>0,05) na percentagem de ovos, conversÃo alimentar, massa de ovo, ganho de peso corporal, peso dos ovos, percentagens da gema, clara e casca, e na reduÃÃo do nÃvel de colesterol dos ovos, em relaÃÃo à dieta controle (sem Ãleo). De acordo com a idade das aves, observou-se aumento significativo (P<0,05) do peso dos ovos e da percentagem da gema, e reduÃÃo na percentagem da clara e na coloraÃÃo da gema crua, porÃm nÃo houve alteraÃÃo significativa (P>0,05) na percentagem da casca. O nÃvel de 4% de adiÃÃo do Ãleo vegetal nas dietas promoveu uma melhora efetiva (P<0,05) na coloraÃÃo da gema crua dos ovos. Os ovos conservados em temperatura de refrigeraÃÃo apresentaram menor (P<0,05) perda de peso e melhores (P<0,05) Ãndices de percentagem da clara, gravidade especÃfica, unidades Haugh e coloraÃÃo da gema crua, quando comparados aos ovos conservados em temperatura ambiente. Constatou-se que a qualidade dos ovos à alterada significativamente (P>0,05) em funÃÃo da temperatura de conservaÃÃo e do perÃodo de estocagem, notadamente para os parÃmetros perda de peso, percentagens da gema e clara, gravidade especÃfica e unidades Haugh. Em relaÃÃo à anÃlise sensorial, a inclusÃo de 4% de adiÃÃo de Ãleo de linhaÃa nas dietas alterou (P<0,05) efetivamente o sabor e a textura da gema e da clara dos ovos. Na anÃlise econÃmica, observou-se que a margem bruta e o lucro operacional efetivo foram maiores na dieta com 2% Ãleo de soja e menores na dieta com 4% Ãleo de linhaÃa. A melhor resposta econÃmica da produÃÃo de ovos foi obtida pelas aves que consumiram dieta com 2% Ãleo de soja / The research was developed in the Sector of Poultry of the Department of Zootecnical Center of Agrarian Sciences of the Federal University of Cearà (UFC), objectifying to evaluate the zootecnical performance and the quality of eggs of commercial laying hens, submitted to the diets with different vegetal oils. The experimental procedure involved 224 commercial laying hens of the Hy-line W-36 line, with 23 weeks of age, divided in 5 cycles of 28 days, during which were collected data for study The experiment followed a randomized blocks, distributed in seven treatments, each experimental unit was a box with 8 hens and 4 repetitions per treatment. The treatments consisted of 7 rations, with level of energy of 2850 kcal ME/kg and protein of 18%, being: T1 - basal diet (without oil); T2 - basal diet + 2% of soy oil; T3 - basal diet + 4% of soy oil; T4 - basal diet + 2% of flax oil; T5 - basal diet + 4% of flax oil; T6 - basal diet + 2% of cotton oil and T7 - basal diet + 4% cotton oil. The inclusion of the vegetal oil in the diets did not make possible an absolute improvement (P>0,05) in the egg percentage, feed conversion, egg mass, body weight, egg weight, percentages of the yolk, egg white and shell and did not reduce cholesterol level of eggs, in relation to the basal diet (without oil). In accordance with the age of the birds, significant increase (P<0,05) of the weight of eggs and the percentage of the egg yolk was observed, and reduction in the percentage of the yolk and the coloration of the raw egg yolk, however it does not to have significant alteration (P>0,05) in the percentage of the shell. The level of 4% of addition of the vegetal oil in the diets promoted an effective improvement (P<0,05) in the coloration of the raw egg yolk. The eggs conserved in temperature of refrigeration presented (P<0,05) smaller loss of weight and better (P<0,05) percentage of the yolk, specific gravity, Haugh units and coloration of the raw egg yolk, when compared with eggs conserved in ambient temperature. It was evidenced that the quality of eggs is modified significantly (P>0,05) in function of the temperature of conservation and the period of storage, mainly for the parameters weight loss, percentages of the yolk and, specific gravity and Haugh units. In relation to the sensorial analysis, the inclusion of 4% of oil addition of flax oil in the diets effectively modified (P<0,05) the flavor and the texture of the yolk and the white egg. Economic analysis suggested that the rude edge and the effective operational profit were bigger in the diet with 2% oil of soy and smaller in the diet with 4% flax oil. The best economic reply of the egg production was gotten by the birds that consumed diet with 2% soy oil
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Estudo da produção de biodiesel a partir de óleo de babaçu e etanol utilizando a transesterificação alcalina tradicional com agitação mecânica e assistida por ultrassons / Evaluation of biodiesel production from babassu and ethanol applying traditional alkaline transesterification with mechanical stirring and under ultrasonic technologyEduardo José Mendes de Paiva 27 August 2010 (has links)
Neste trabalho foram sintetizados ésteres etílicos do óleo de babaçu através da catálise alcalina em meio homogêneo. O planejamento de experimentos foi utilizado como ferramenta de otimização e também na identificação dos principais fatores que influenciam nas conversões em ésteres etílicos. As reações de transesterificação foram realizadas através de duas metodologias de processo - a tradicional com agitação mecânica e a promovida por ondas ultrassônicas. A espectrometria de ressonância magnética nuclear foi utilizada na quantificação das conversões de todos os experimentos e a análise termogravimétrica foi empregada na determinação da pureza dos ésteres etílicos e do principal subproduto da reação - o glicerol. Matrizes ortogonais de Taguchi foram utilizadas para o desenvolvimento deste estudo. Os fatores independentes avaliados na transesterificação tradicional foram: razão molar etanol/óleo, temperatura, turbulência, razão ponderal catalisador/óleo, tempo e os tipos de catalisadores mais comumente empregados (NaOH e KOH). Os ensaios envolvendo a transesterificação clássica foram realizados sob atmosfera de nitrogênio e também sob atmosfera normal. Com o método sonoquímico foram avaliados os fatores: razão molar, tempo, razão ponderal catalisador/óleo e tipo de catalisador. O delineamento experimental mostrou que o principal fator a influenciar nas conversões em ésteres etílicos com ambos os métodos é a razão molar. Destaca-se ainda na transesterificação alcalina tradicional, a influência das interações entre a temperatura e o tempo, mostrando que melhores conversões são obtidas com temperaturas próximas a ambiente (27 a 30ºC). De acordo com o modelo obtido através do delineamento experimental, conversões superiores a 99% são obtidas quando a razão estequiométrica é ajustada em 6:1, utilizando-se 1,0% de KOH, sob agitação mecânica a 400rpm durante 60min. A influência da atmosfera de nitrogênio mostrou-se pouco significativa para a reação e conversões semelhantes foram obtidas com atmosfera normal. A transesterificação alcalina assistida por ondas ultrassônicas apresentou os melhores resultados em relação ao tempo de reação e de separação entre as fases glicerínica e de ésteres etílicos. O modelo experimental mostrou que conversões superiores a 99% podem ser obtidas em 10 minutos ajustando as variáveis independentes nos seguintes valores: razão estequiométrica em 6:1 com 1,0% de KOH. Em ambos os métodos o catalisador KOH mostrou-se superior ao NaOH, especialmente durante as etapas de purificação. A estratégia de purificação dos ésteres etílicos adotada consistiu na utilização de um solvente (hexano) e lavagens com HCl 0,1 mol.L-1 que foi otimizada para 12,5% de solução em relação ao peso de ésteres obtidos, coletados logo após a separação de fases. O rendimento mássico obtido com o modelo experimental, após procedimentos de lavagens mencionados, foi de 94,59%. O trabalho demonstrou que o processo de obtenção de biodiesel de babaçu apresenta ótimos rendimentos desde que os parâmetros de reação sejam otimizados. A sonoquímica mostrou-se potencialmente promissora para obtenção de elevadas conversões em curtos intervalos de tempo. / In this work ethyl esters of babassu oil were synthesized by alkaline catalysis in homogeneous medium. The experimental design was used as a tool for optimization of the transesterification reaction and also in identifying key factors influencing the conversion into ethyl esters. The transesterification reactions were performed using two methods of process - the traditional mechanical agitation and agitation promoted by sound waves. The nuclear magnetic resonance spectroscopy was used to quantify the conversion of all reactions of transesterification and thermogravimetric analysis was used to determine the purity of ethyl esters and the main byproduct of the reaction - the glycerol. Taguchi orthogonal arrays were used to develop this study. The independent factors evaluated in the transesterification traditional were: molar ratio ethanol / oil, temperature, stirring speed, weight ratio catalyst / oil, time and the types of most commonly used catalysts (NaOH and KOH). The classical experiments involving the transesterification were performed under nitrogen atmosphere and also under normal atmosphere. With the sonochemical method were evaluated the following factors: molar ratio, time, weight ratio catalyst / oil and type of catalyst. The experiment showed that the main factor influencing the conversion into ethyl esters in both methods is the molar ratio. The best conversion results were obtained with twice the stoichiometric quantity. Also noteworthy in the traditional alkaline transesterification is the influence of interactions between temperature and time, showing that the best conversions are obtained with temperatures close to ambient (30°C) in 60 minutes. According to the model obtained by the experimental design, conversions above 99% are obtained when the stoichiometric ratio is set at 6:1, with 1.0% KOH, under stirring at 400 rpm. The influence of nitrogen atmosphere was less significant for the reaction and similar conversions were obtained with normal atmosphere. Alkaline transesterification assisted by sound waves produced the best results with respect to time of reaction and phase separation of glycerin and ethyl esters. The experimental model showed that conversions above 99% can be obtained in 10 minutes by adjusting the independent variables in the following values: in the stoichiometric ratio 6:1 with 1.0% KOH. In both methods the KOH catalyst was superior to NaOH, influence also noted during the purification steps. Experimentally it was found that the formation of emulsions and gels are more frequent with the use of the sodium hydroxide catalyst. The strategy for purification of ethyl esters adopted was the use of a solvent (hexane) and washing with HCl 0.1 mol.L- 1 that was optimized for 12.5% solution by weight of esters obtained, collected just after phase separation. The mass yield obtained with the experimental model, after washing procedures mentioned, was 94.59%. The study showed that the process of obtaining babassu biodiesel has good yields since the reaction parameters are optimized. The sonochemical proved to be potentially promising for achieving high yields in short time, which might be an excellent route for production aiming to meet the high market demands.
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Avaliação consequencial do ciclo de vida: inventário do uso solo para produção prevista de biodiesel no Brasil em 2030Novak, Luis Henrique 30 July 2013 (has links)
CAPES / As emissões de gases de efeito estufa (GEE) vêm gerando graves mudanças no clima mundial. Uma das soluções propostas para mitigar o problema é a substituição dos combustíveis fósseis por biocombustíveis. A eficácia dessa medida tem sido questionada, tendo em vista as possíveis consequências indiretas da produção agrícola. A Avaliação Consequencial do Ciclo de Vida é um método de avaliação ambiental de produtos que inclui efeitos indiretos. Diante disso, o objetivo do presente trabalho é aplicar o método para obtenção de um inventário do uso agrícola do solo necessário para incrementar a produção de óleo vegetal visando atender a mudança na demanda de biodiesel no Brasil prevista para o período 2010-2030. Das matérias-primas consideradas (soja, amendoim, algodão, dendê, girassol e canola), o estudo mostra que o óleo de dendê é a matéria-prima marginal e apenas 5% da área potencial para plantio de dendê seria utilizada para atender ao incremento na demanda de biodiesel. A área necessária diretamente pelo dendê seria de 2,1 milhões de hectares na região Norte do Brasil. A torta de amêndoa, co-produto dependente do processo multifuncional do dendê, pode substituir o farelo de soja usado como ração, evitando o plantio de 0,6 milhões de hectares de soja. Assim, o inventário final do uso do solo é um incremento 1,5 milhões de hectares para produção agrícola na região Norte do Brasil. Foram desenvolvidos cenários alternativos: produtividade do dendê constante, mudança no horizonte temporal (2010-2020) e mudança na taxa de crescimento do co-produto determinante. Não houve alteração no resultado do estudo para os cenários considerados. / Greenhouse gas emission has several negative consequences on worldwide climate. Biofuels have been considered one of the solutions to mitigate this problem by substitution of fossil fuel. However, indirect effects should be included in order to produce more reliable results in environmental assessment. In this context, Consequential Life Cycle Assessment is a method that can fill this gap. The objective of this work is to use the method to obtain the agricultural land use inventory to meet the biodiesel demand change in Brazil, considering the period 2010-2030. Only the main feedstock were included (soybean, peanut, cottonseed, palm, sunflower and canola). From these, the study found the palm oil as the marginal one. Around 5% of the potential area for palm would be used to meet the biodiesel demand change. The increased area would be 2,1 million hectares in North region of Brazil. The palm meal, which is a dependent co-product from multifunctional process, can substitute soybean meal as animal feed. The substitution avoids 0,6 million hectares of soybean in North region. Finally, the net land use inventory is 1,5 million hectares in North region of Brazil. Three alternative cenarios were developed: palm productivity unchanged, a different time horizon (2010-2020) and a different increasing rate for the determinant co-product. The same result was found for all cenarios.
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