Orientador: Antonio Marsaioli Junior / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos / Made available in DSpace on 2018-08-03T16:21:01Z (GMT). No. of bitstreams: 1 Vilalba_FabiodeAlbuquerque_M.pdf: 570013 bytes, checksum: 8f4e3f0349848d620390519a1dc8eee4 (MD5) Previous issue date: 2003 / Resumo: O cupuaçu (Theobroma grandiflorum) é uma fruta nativa da região amazônica Brasileira cujas sementes convenientemente fermentadas, secas e torradas podem ser utilizadas para a obtenção de um produto similar ao chocolate. Uma etapa deste processo deverá também envolver, portanto, a obtenção dos nibs (cotilédones fragmentados) das amêndoas secas, separando-o da casca e do gérmen, o que pode ser feito antes ou após a torração. Esta fase do processamento da amêndoa é, ainda, realizada manualmente, de modo totalmente artesanal e pouco eficiente. O objetivo deste trabalho consistiu em pesquisar uma forma alternativa de quebra da amêndoa seca sem torrar, realizada através de um beneficiador de cilindros, seguida da utilização de um jogo de peneiras para a separação das frações. Os fatores estudados no rendimento da obtenção dos nibs e na verificação de sua pureza (percentual de casca e gérmen) foram a umidade da amêndoa inteira e a velocidade diferencial do par de cilindros de borracha do beneficiador, sendo este último a diferença das velocidades tangenciais destes cilindros. Os valores estudados das umidades foram de 5, 6 e 7%. O fator velocidade diferencial foi estudado em duas faixas, a primeira com 2,10 , 2,66 e 3,23m/s e, a segunda, com 0,84 , 1,87 e 3,23m/s. Pelos resultados obtidos, foi verificado que a variável umidade apresenta a maior influência na quebra das amêndoas. O nível de umidade de 5% da amêndoa inteira apresentou os maiores rendimentos de obtenção de nibs. A velocidade diferencial não apresentou diferença significativa nos rendimentos. Em relação aos valores dos percentuais de casca e gérmen nos nibs, nenhuma variável em estudo apresentou influência significativa nos valores desta resposta, mesmo assim todos os resultados foram bastante satisfatórios. Os percentuais de casca e gérmen encontrados no material final (nibs) foram inferior a 1,75%. O rendimento deste processo alternativo está em torno de 90% de obtenção dos cotilédones encontrados em uma determinada massa de amêndoas. Concluindo, o processo proposto constitui uma alternativa mecanizada, tecnicamente válida e superior aos métodos artesanais, apresentando bom rendimento de recuperação dos nibs, com percentuais de casca e gérmen abaixo do tolerado / Abstract: Cupuassu (Theobroma grandiflorum) is a native fruit from the Brazilian Amazon region whose seeds suitably fermented, dried and roasted can be used to manufacture a product similar to chocolate. One phase of this process must also include, therefore, the extraction of nibs (scrapped cotyledons) from the dried kernels, separating it from the shells, what can be done before or after roasting. This part of processing the kernels is still done through manual operation, in an inefficient artisan way. This work aims at devising an alternative way of cracking the dried but not roasted kernels by using a roller crusher, followed by sieving for separating the fractions. The variables studied for determining the nibs acquisition yield as well the purity of such material (expressed as percentage of shell and embryo fragments) were the moisture of the whole kernel and the differential speed of the double rollers of the crusher, this last is the difference of the tangential speeds of those rollers. The studied values of the moisture were 5, 6 e 7%. The factor differential speed was studied in two bands, the first with 2.10 , 2.66 e 3.23m/s, the second with 0.84 , 1.87 e 3.23m/s. The results confirmed that the moisture of the whole kernel was the variable that most influenced the cracking of the kernels. The moisture level of 5% of the whole kernels showed greater yield obtainment of nibs. The variation of the differential speed did not present any significant difference at yield. With regard to the percentage values of shell and embryo found in nibs, the variables considered did not show any significant difference on the response parameter, although the results were very much satisfactory. The percentage of shell and embryo found in the final material (nibs) is below the 1.75%. The yield of this alternative process is 90% of the cotyledons acquisition from certain kernels mass. In conclusion, the proposed process sets up as a mechanized alternative, of technical value and superior to the artisan methods, showing good nibs acquirement yield, and percentage of shells and embryo below the tolerated. / Mestrado / Mestre em Engenharia de Alimentos

<p>Non-invasive electromagnetic brain stimulation uses electrodes and/or coils to modulate brain activity via the induced E-fields. E-field dosimetry solvers have improved non-invasive electromagnetic brain stimulation protocol and our understanding of neuroscience. However, E-field dosimetry techniques are incomplete in that the contributions of non-linear neuron activity are left unaccounted for. To better understand the neurological effects of non-invasive electromagnetic stimulation, we introduce an integral equation formulation for modeling the non-linear behavior of neurons due to an incident E-field generated by electrode and coil sources. We formulate the new integral equation using a boundary element approach. We compare the boundary element solver accuracy with an established finite element solver and multi-scale cable equation approaches. Unlike previous approaches, this new boundary integral formulation avoids multi-scaling challenges from meshing while retaining the accuracy and the robust spatial support of integral equation-based methods. The memory savings from switching to surface meshes makes simulations with more complex morphologies computationally tractable. Additionally, we examine the ability of neurons to couple to one another via the local extracellular fields. Examples of simulations with both transcranial electric and magnetic stimulation results for simple geometries are used to illustrate the capabilities of a boundary integral approach. This boundary integral method will aid the development of better neurological understanding, delineate the mechanisms by which electromagnetic stimulation engenders neuronal activity, and aid in modeling local E-field coupling.</p>

L'Organisation Internationale de Labellisation du Commerce Equitable FLO ( Fairtrade Labelling Organization ) a la responsabilité de l'élaboration des standards du Commerce Equitable pour les organisations de petits producteurs dans trois volets, soit les volets économique, social et environnemental. FLO élabore aussi des standards commerciaux pour les produits labellisés Commerce Equitable (aussi appelés dans ce travail : produits équitables) ; pour exemple, Max Havelaar est l'un des labels qui certifient que la production et la commercialisation d’un produit sont faits selon des standards du Commerce Equitable. Alors qu'il existe des informations sur le prix minimum du Commerce Equitable pour les fèves de cacao (Theobroma cacao) ou sur le prix équitable (prix minimum du Commerce Equitable + un prime) Free on Board (FOB) que reçoivent les producteurs certifiés Commerce Equitable de cacao de pays du Sud, il n’y a pas assez d’informations sur les prix que reçoit le producteur équitable « à la porte de sa ferme ». Afin de mieux connaître le prix équitable que reçoivent « directement » les producteurs de cacao, nous avons sélectionné la Coopérative « Le CEIBO » en Bolivie. Une démonstration basée sur l’étude du cas du prix des fèves de cacao et la comparaison du prix équitable et du prix conventionnel dans la Région de Alto Beni. Bien que le CEIBO soit en situation de monopsone, la tendance du pourcentage de prix FOB que reçoivent les petits producteurs de fèves de cacao d'Alto Beni en général est à la hausse entre la période 2000-2006. / The International Fair-Trade Labelling Organization has the responsibly of elaborating the norms of fair-trade applied to the organisations which group small producers in three sectors i.e. Economical, social and environmental. FLO also sets the trade standards for the products labelled Fair Trade (also named in this work: fair products): for example, Max Havelaar is one of the labels which certifies the production and commercialisation of a product made as per the norms of fair trade. Although there is some information on the minimum price for fair trade concerning the cocoa-nibs (Thobroma cacao) or on the fair price (minimum price for fair trade + Subsidy) Free On Board (FOB) which are allowed to the certified fair trade cocoa producers in Southern countries, there is not enough information about the price perceived by the fair trade producer at the “Farm Gate”. In order to know better the fair price that the producers of cocoa receive “directly”, we have chosen the Cooperative “Le CEIBO” in Bolivia, a model based on the study of the price of the cacao-nib and the comparison with the fair price and the conventional price in the Alto Beni region. Though the CEIBO is in a situation of monopsony, the perception of the small cacao-nibs producers is that the percentage of the FOB price has generally risen between 2000-2006 in Alto Beni.