279 resultados para óleos e graxas


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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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Pós-graduação em Engenharia e Ciência de Alimentos - IBILCE

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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Pós-graduação em Agronomia (Horticultura) - FCA

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Once petroleum is na exhaustible source of energy, alternative fuels are having more prominence. A much discussed option for replacing fossil fuels is the use of biofuels derived from oils or fats, especially biodiesel. The biodiesel preparation is through a reaction named transesterification, a reaction of triglycerides with a short chain alcohol with a catalyst, producing a mixture of fatty acid esters and glycerol. According to ANP (National Petroleum Agency) specifications, biodiesel can have contaminants due to the catalyst or oil used on its synthesis, such as phosphorus, wich can damage the catalytic converter and cause significant increase in the particles emission. This project aims to develop na alternative method using chemically modified electrodes with iron nanoparticles for determination of phosphorus in biodiesel. For the formation of the iron nanoparticles film on the surface of a glassy carbon electrode, was used a iron sulfate solution. The film was formed after 10 successive cycles, with a scanning speed of 50 mV s-1 and a potential range of -0,9 to -1,25 V. To reduce possible oxides on the surface and activate the electrode, it has been subjected to a cathodic polarization with a potential of -1,25 V for 15 minutes in a sodium hydroxide solution. In cyclic voltammograms obtained in the study of the speed of scanning, there is an increase in the intensity of the anodic and cathodic current peaks. The cathodic peak current varied linearly with the square root of scan rate, showing that the electrode is controlled by diffusion. After successive additions of phosphate there is a linear variation in the current peak in the concentration range of 1,0 x 10-7 a 1,0 x 10-6 mol L-1. To determine if the concentration of phosphorus in real sample, the method of adding standard was used by adding aliquots of phosphate ions in the solution containing soy biodiesel extracted with ....

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Pós-graduação em Agronomia (Horticultura) - FCA

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Pós-graduação em Agronomia (Horticultura) - FCA

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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

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A presente invenção apresenta a síntese do peptídeo AcWahxKTTKS, onde foi adicionada à “sequência mãe” (KTTKS) uma molécula de ácido capróico, que é um ácido graxo insaturado composto por 6 átomos de carbono, encontrado naturalmente nas gorduras e óleos minerais, para conferir um grau de lipofilicidade ao peptídeo e favorecer na permeabilidade do mesmo na pele. Adicionou-se também o triptofano, que é um aminoácido aromático essencial para a nutrição humana, visando proporcionar fluorescência ao peptídeo e assim quantificá-lo na pele através de um método mais eficiente e sensível. O triptofano foi acetilado para diminuir a interação do peptídeo com a água, a fim de ajudar na penetração do peptídeo na pele. O peptídeo AcWahxKTTKS estimula a síntese de colágeno nos fibroblastos, reduzindo ou eliminando, desta forma, as rugas e linhas de expressão na pele.

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Pós-graduação em Agronomia - FEIS

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This study aimed at investigating, in the national and international scientific literature, how aromatherapy is used as a therapeutic tool to reduce anxiety. It is a bibliographic study that adopted integrative literature review as a method. Studies published on databases Scielo, Medline and Cinahl from 2008 to 2012 were selected. A sample of 20 scientific articles was analyzed, and of these, 13 had an experimental and a quasi--experimental design whereas 07 were systematic or integrative reviews. The synthesis of knowledge sho-wed that aromatherapy represents a safe therapeutic practice although it is still underestimated in health care practices. The construction of evidence levels was not possible due to discrepancies in the studied populations, in research designs, the various essential oils used and the different methods for aromatherapy application. The knowledge gaps identified in these studies are related to the need to develop new forms to evaluate the effectiveness of this practice, including the therapist-patient relationship and the different communication forms that are intrinsic to aromatherapy.

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There is a great global concern about the depletion and the high cost of fossil fuel reserves exploitation, more than ever, it is necessary to make a profound study and take advantage of alternative sources that can be used as energy efficiency with an appropriate pricing and low environmental impact. Brazil, which has highlighted using alternative energy sources as the use of ethanol and, in recent years, has been encouraging the expansion of its energy matrix in which the biodiesel will have a strategic importance within the agrobusiness area. Biodiesel is a fuel that can replace the diesel, which is a petroleum derivative. It is an ester, produced in the transesterification reaction of vegetable oils and animal greases, in an alcohol with an additional catalyst, are converted into fatty acids and result in esters with glycerol as sub products. The objective of this study was to estimate the final energy balance for the process biodiesel production from oil chicken waste. The energy balance estimation was quantified in calorific value according to the energy expenditure by calorimetric bomb method. The relationship between input and output of energy was around 0.97. In a first evaluation, the procedures adopted should be improved enough, so the process can become energetic and economically viable.