Peanuts (Arachis-hypogaea) are one of the staples in Ghana, Sub-Saharan Africa, and other developing countries. This leguminous crop is frequently contaminated with aflatoxins, which are secondary metabolites of some Aspergillus fungi, mostly Aspergillus. flavus and Aspergillus parasiticus. Aflatoxins in foods are known to cause liver cancer, stunted growth in children, immune system disorders and economic losses. Aflatoxin contamination of peanuts during storage is worse in the tropics because climatic storage conditions there are almost the same as the optimum conditions for Aspergillus growth: temperature conditions of about 26-43 °C and relative humidity of 62-99%. This study investigated the growth of Aspergillus and the production of aflatoxin in shelled peanuts under varying treatment and packaging conditions. In addition, the appropriate pre-storage treatments and packaging needed to reduce aflatoxin production and to maintain quality of shelled and in-shell peanuts in storage under tropical environments were studied. Another aim was to determine the impact of the switch to hermetic storage on peanut farming and marketing profitability in Ghana. Different peanut treatments, with and without Aspergillus flavus fungi, were packaged in different systems; specifically, polypropylene woven sacks and hermetic packaging. Peanuts were analyzed for fungi growth, aflatoxin production and lipid oxidation (peroxide value and p-Anisidine value). Partial roasting and blanching of peanuts eliminated aflatoxigenic fungi and halted aflatoxin production in stored peanuts, increased the effectiveness of peanut sorting and, hence, helped reduce or eliminate aflatoxin levels along the peanut value chain. Additionally, the results of this study demonstrated that hermetic storage, by suppressing aflatoxin production, has the potential for maintaining peanut quality vis a vis polypropylene woven packaging. Profitability analysis conducted as part of this study revealed that the use of the hermetic storage system would not only improve farmer and trader profits, but also reduce the incidence of various ailments attributed to aflatoxins. / Ph. D. / Peanuts are one of the staple crops in Ghana, Sub-Saharan Africa, and other developing countries. This crop is frequently contaminated with a special type of molds which produce a poisonous substance called aflatoxin. In foods, it is known to cause liver cancer, stunted growth in children, immune system disorders and economic losses. Aflatoxin contamination during storage in the tropical regions is worst because peanuts are mostly packaged in polypropylene woven sacks and stored under environmental conditions. Unfortunately, climatic conditions promote mold growth and aflatoxin production. In view of this problem, this study was aimed at finding appropriate, affordable and adoptable storage solutions to control fungi growth and aflatoxin production. A portion of the shelled peanuts was partially roasted to kill the molds and to stop aflatoxin production, and then peeled to facilitate the sorting of discolored peanuts which are believed to contain aflatoxins. The partially roasted peanuts and raw ones were packaged in conventional polypropylene woven sacks and hermetic packaging system and stored. It was demonstrated that partial roasting and peeling of peanuts can kill molds and halt aflatoxin production in stored peanuts. Partial roasting increased the effectiveness of peanut sorting and hence, aided in reducing aflatoxin levels along the peanut value chain. Additionally, the results of this study have shown that, compared to polypropylene woven sacks, hermetic storage suppresses mold growth because it eliminates oxygen from the package and results in lower aflatoxin levels and reduces the rate of quality deterioration. Profitability analysis conducted as part of this study revealed that the use of the hermetic storage system would not only improve farmer and trader profitability, but also help reduce the incidence of various ailments that have been attributed to aflatoxins. With the high potential of making additional profits when the hermetic packaging system is adopted, I recommend that local production and marketing of a hermetic storage system be encouraged, along with the active creation of awareness of their benefits in reducing the incidence of aflatoxins.

O poeta italiano Vittorio Sereni (1913-1983) é ainda inédito e pouco conhecido no Brasil. A fim de introduzir o autor ao público brasileiro, este trabalho tem como objeto de estudo seu livro de estreia, Frontiera, de 1941. A partir de um panorama que percorre de maneira sucinta o surgimento dos poetas modernos da Itália, e que situa o leitor acerca da posição ocupada por Vittorio Sereni nesse cenário, esta pesquisa investiga os caminhos cursados pelo poeta em sua juventude, no início de sua produção literária. Tal percurso, conforme se demonstrará, foi determinante para sua completa formação humana, cultural e intelectual, abrangendo, por exemplo, as aulas do filósofo Antonio Banfi na Universidade de Milão, a experiência como redator da revista \"Corrente di vita giovanile\", e a admiração e amizade com os poetas Eugenio Montale, Giuseppe Ungaretti e Umberto Saba. Ademais, este trabalho discute o polêmico tema do pertencimento ou não de Sereni ao movimento hermético italiano dos anos 30/40. Finalmente, por meio de análises de quatro poemas do livro selecionado, \"Inverno\", \"Inverno a Luino\", \"Strada di Zenna\" e \"Ecco le voci cadono\", serão especificadas algumas linhas temáticas centrais de Frontiera recorrentes em outras composições de sua primeira publicação. / Italian poet Vittorio Sereni (1913-1983) is still unpublished and relatively unknown in Brazil. In order to introduce the author to the Brazilian public, this research studies his debut book, Frontiera, 1941. Through a brief overview of the history of the Italian modern poets, the present study investigates the path followed by Vittorio Sereni during his youth, at the beginning of his literary career. Such path, as will be shown later, was of the utmost importance for the poets humanitarian, cultural and intellectual development, and includes the philosophy lectures given by Antonio Banfi at the University of Milan, the time spent as a writer at the magazine \"Corrente di vita giovanile\" and the admiration of and friendship with fellow poets Eugenio Montale, Giuseppe Ungaretti and Umberto Saba. Moreover, this research addresses the controversial debate on whether Sereni integrated or not the Italian hermetic movement in the 1930s and 40s. Lastly, through the study of four poems from the selected book, \"Inverno\", \"Inverno a Luino\". \"Strada di Zenna\" e \"Ecco le voci cadono\", recurrent central themes in Frontiera will be presented and analyzed.

Les micro-dispositifs comportant des structures libérées et mobiles sont d’une part très sensibles aux variations de leur environnement de travail, et d’autre part très fragiles mécaniquement. L’étape de découpe du substrat en plusieurs puces est extrêmement agressive et peut entrainer la destruction totale des micro-dispositifs. L’encapsulation avant la découpe va alors prémunir les micro-composants lors de cette étape critique et continuer à garantir leur bon fonctionnement tout au long de leur utilisation en conservant la stabilité et la fiabilité de leur performance. Le conditionnement doit en outre interfacer les micro-dispositifs encapsulés avec le monde macroscopique en vue de leur utilisation. De nombreux procédés de fabrication ont déjà été développés pour l’élaboration d’un conditionnement. C’est le cas de l’encapsulation puce par puce, substrat - substrat, par couche sacrificielle par exemple. Ils sont toutefois très contraignants (encombrement, compatibilité, coût, …). Nous avons étudié, au cours de cette thèse, un procédé innovant de conditionnement hermétique par transfert de film utilisant une couche à adhésion contrôlée. Cette technologie consiste à élaborer des capots protecteurs sur le substrat moule puis à les reporter collectivement pour encapsuler les micro-dispositifs. Ce procédé est totalement compatible avec un interfaçage électrique de composant qui traverse les cordons de scellement ou le capot. Ce procédé nécessite la maîtrise de la croissance de divers films (C, CxFy, Ni, AlN, parylène, BCB, Au-In) et permet d’obtenir des boitiers étanches, hermétiques et robustes qui devraient très rapidement pouvoir être utilisés pour le conditionnement de MEMS. / Micro-devices which are composed of free standing or mobile structures are very sensitive to the working condition and mechanically very fragile. The saw dicing steps is very aggressive and it can destroy the micro-devices. Packaging will prevent the micro devices from any damage during this critical step and also take care of it all along its life by controlling its performance stability and reliability. Moreover, the suited devices use needs a connection to the macroscopic word through the packaging. Many packaging process flow has already developed such as pick and place, wafer to wafer, thin film packaging with a sacrificial layer. Nevertheless, they have got many drawbacks (footprint, process compatibility, cost …). We have developed an attractive wafer level hermetic packaging process by film transfer technology during this these. It relies on a transferred molded film cap from a carrier wafer to the donor wafer. Electrical path can be done through the cap or the bonding ring. Cap manufacturing need a high layer growth skill for example in C, CxFy, Ni, AlN, parylène, BCB, Au-In films to make robust, hermetic encapsulation which should be soon used for MEMS packaging.

Muovendo da una vasta ricognizione sulle riviste letterarie degli anni Trenta, la ricerca si è concentrata sui principali periodici a cui hanno collaborato poeti e critici ermetici: Interessanti si sono rivelati i rapporti epistolari tra i poeti e i direttori e redattori delle riviste: nella tesi sono state riportate le lettere più significative, con privilegio per quelle inedite. Sono stati riportati diversi documenti di natura critico-teorica, alcuni testi poetici rari di Mario Luzi (mai confluiti in una silloge e mai riproposti da alcuno studioso) e sono state antologizzate (con trascrizione dei testi e apparato in calce) le liriche di alcuni poeti che presentano varianti rispetto all'ultima edizione in volume: si tratta di versi di Mario Luzi, Umberto Saba, Carlo Betocchi, Giuseppe Ungaretti, Salvatore Quasimodo, Alessandro Parronchi. Almeno un terzo della tesi è dedicato a questo. / Starting from a wide investigation in the literary reviews in the '30s, the research has focused on the major magazines, for which hermetic poets and critics worked. The correspondence between poets and editors in chief and members of the editorial staff has proved extremely interesting; the most meaningful letters, especially the unpublished ones, are presented in the thesis. Many critic-theoretic documents and some rare poetries by Mario Luzi (never collected nor published by critics) are also reproduced. Moreover lyrics by various poets, such as Mario Luzi, Umberto Saba, Carlo Betocchi, Giuseppe Ungaretti, Salvatore Quasimodo, Alessandro Parronchi, have been anthologised (with text transcription and apparatus criticus below); all of them present some changes in text compared to the final version, printed in volume. This analysis represents, at least, the third part of the thesis.

Oil feed grooves are implemented in reciprocating compressor piston applications to assure a constant supply of lubricating oil on bearing surfaces and decrease friction loss. In a hermetically sealed compressor, due to small clearances encountered, oil supply becomes critical in order not to operate in boundary lubrication regime. Due to the small size of the piston and small piston &ndash / cylinder clearance, a partial lubrication regime is present. In the current study, a model that solves Reynolds&rsquo / equation for piston-cylinder lubrication and the average Reynolds&rsquo / equation that considers the effect of roughness on partially lubricated bearing for a compressor piston with oil feed grooves is developed. A parametric study is carried out to investigate the effects of piston design parameters and then arrive at an improved piston performance by using alternative designs for oil feed groove and the other design parameters.

[pt] O presente trabalho trata da simulação de um compressor hermético alternativo operando em regime transiente. O modelo desenvolvido expande, para a simulação do regime transiente, de modelos de regime permanente existentes na literatura. No presente modelo o sistema é dividido em volumes de controle (motor, compressor, muflas, câmaras de sucção e de descarga, reservatório de óleo, linha de descarga, entre outros). Adota-se o modelo de parâmetros concentrados e aplicam-se as equações fundamentais de conservação, resultando em um sistema de equações diferenciais ordinárias. Especial atenção é dedicada à formação de espuma durante a partida. Sob tais condições, pode-se chegar à sucção de óleo por parte do compressor, com conseqüentes danos às partes móveis do conjunto mecânico. Em função da ausência de informação na literatura sobre formação de espumas em compressores herméticos, construiu-se um aparato experimental para reproduzir tais condições em laboratório. Utilizou-se uma combinação de refrigerante R134a e óleo poliol-ester, que foi submetida a condições controladas de despressurização, a partir de uma pressão inicial prescrita. O processo de formação de espuma (taxa, espessura e diâmetro de bolha) foi monitorado com o auxílio de uma câmara de vídeo digital. Uma série de corridas foi efetuada para diferentes concentrações de óleo e taxas de despressurização. Os dados experimentais permitiram estabelecer um modelo semiempírico de formação de espuma no interior de um compressor hermético. Simulou- se, também, o escoamento turbulento tridimensional de refrigerante no interior da carcaça. / [en] The present work is related to the simulation of a reciprocating hermetic compressor operating in transient regime. Hermetic compressors consist of a motor-compressor assembly hermetically sealed in a welded steel shell. Main components are: electric motor, suction and discharge mufflers, discharge line and the compressor itself, formed by the suction and discharge chambers, the pistondriving mechanism assembly and the cylinder body. The model here presented extends existing thermodynamic steady-state models for the transient operational condition. The system is divided into a number of control volumes, for which homogeneously distributed properties is assumed and fundamental conservation equations are applied. Special attention is given for foam formation, during startup. In such conditions, liquid oil can be drawn into the cylinder, causing a deterioration in the performance. Information on the phenomenon is scarce, which led to an effort of reproducing it at laboratory conditions. A saturated mixture of R134a and polyolester oil, at a given pressure, was submitted to controlled depressurization. The foam formation process (rate, height and bubble size) was measured with the help of a digital video camera. A number of runs were carried out, for different pressure drop rates and initial refrigerant concentrations. The experimental data was employed to adapt an existing model of foam formation. A new function for the volume rate of coalescence of gas bubbles was empirically determined. Computational Fluid Dynamics techniques were also used to predict the turbulent three-dimensional flow of refrigerant in the shell side.

Submitted by Gabriela Lopes (gmachadolopesufpel@gmail.com) on 2018-07-17T18:43:22Z No. of bitstreams: 1 Dissertação André Capilheira pós defesa.pdf: 800960 bytes, checksum: 776bae866c79a3b55b3dd16f9cb0751c (MD5) / Approved for entry into archive by Aline Batista (alinehb.ufpel@gmail.com) on 2018-07-17T21:41:26Z (GMT) No. of bitstreams: 1 Dissertação André Capilheira pós defesa.pdf: 800960 bytes, checksum: 776bae866c79a3b55b3dd16f9cb0751c (MD5) / Approved for entry into archive by Aline Batista (alinehb.ufpel@gmail.com) on 2018-07-17T21:43:36Z (GMT) No. of bitstreams: 1 Dissertação André Capilheira pós defesa.pdf: 800960 bytes, checksum: 776bae866c79a3b55b3dd16f9cb0751c (MD5) / Made available in DSpace on 2018-07-17T21:48:58Z (GMT). No. of bitstreams: 1 Dissertação André Capilheira pós defesa.pdf: 800960 bytes, checksum: 776bae866c79a3b55b3dd16f9cb0751c (MD5) Previous issue date: 2016-09-06 / As características dos materiais utilizados nas embalagens para armazenamento de sementes podem influenciar negativamente no processo de deterioração, acarretando problemas futuros no período de armazenamento e na emergência em campo. Desta forma, objetivou-se avaliar a qualidade fisiológica de sementes de soja, armazenadas em embalagens permeável e hermética e mantidas em condições ambientais não controladas. Para a realização do experimento foi utilizado um lote de sementes de soja da cultivar SYN 1059 RR. Foi empregado quatro repetições, distribuídas em parcela dividida 3x6 (três tipos de embalagens x seis períodos de armazenamento). Foram utilizadas embalagens de papel multifoliado, hermética e hermética com injeção de CO2, armazenadas por 225 dias e avaliação em intervalos regulares de 45 dias. Após o ensaque das sementes de soja, foi avaliada a qualidade das sementes através das análises de germinação, envelhecimento acelerado, umidade, condutividade elétrica e emergência em campo. A embalagem hermética, com e sem injeção de CO2, favorece a diminuição da velocidade da deterioração das sementes de soja. A embalagem hermética permite uma maior qualidade fisiológica das sementes de soja comparativamente à embalagem permeável, no período de armazenamento até 180 dias sobre as condições ambientais não controladas. / The characteristics of materials used in packages for seeds storage may negatively influence in the deterioration process, causing future problems in the period of storage and in the emergence in the field. Thus, we aimed to assess the physiological quality of soya beans, stored in permeable and hermetic packages and stored in uncontrolled environmental conditions. In order to carry out the experiment, we used a soya beans lot from the cultivar SYN 1059 RR. It was used four repetitions, distributed in divided portion 3x6 (three types of packages x six storage periods). We used multi-wall paper, hermetic and hermetic with CO2 injection packages, stored for 225 days and an assessment of regular intervals of 45 days. After bagging the soya beans, the beans quality was assessed through the analysis of germination, accelerated aging, humidity, electric conductivity and emergence in the field. The hermetic package, with and without CO2 injection, favors to reduce the speed of deterioration of soy bean seeds. The hermetic package allows a higher physiological quality of soya beans comparatively to the permeable package, in the storage period of up to 180 days under uncontrolled environmental conditions.

O poeta italiano Vittorio Sereni (1913-1983) é ainda inédito e pouco conhecido no Brasil. A fim de introduzir o autor ao público brasileiro, este trabalho tem como objeto de estudo seu livro de estreia, Frontiera, de 1941. A partir de um panorama que percorre de maneira sucinta o surgimento dos poetas modernos da Itália, e que situa o leitor acerca da posição ocupada por Vittorio Sereni nesse cenário, esta pesquisa investiga os caminhos cursados pelo poeta em sua juventude, no início de sua produção literária. Tal percurso, conforme se demonstrará, foi determinante para sua completa formação humana, cultural e intelectual, abrangendo, por exemplo, as aulas do filósofo Antonio Banfi na Universidade de Milão, a experiência como redator da revista \"Corrente di vita giovanile\", e a admiração e amizade com os poetas Eugenio Montale, Giuseppe Ungaretti e Umberto Saba. Ademais, este trabalho discute o polêmico tema do pertencimento ou não de Sereni ao movimento hermético italiano dos anos 30/40. Finalmente, por meio de análises de quatro poemas do livro selecionado, \"Inverno\", \"Inverno a Luino\", \"Strada di Zenna\" e \"Ecco le voci cadono\", serão especificadas algumas linhas temáticas centrais de Frontiera recorrentes em outras composições de sua primeira publicação. / Italian poet Vittorio Sereni (1913-1983) is still unpublished and relatively unknown in Brazil. In order to introduce the author to the Brazilian public, this research studies his debut book, Frontiera, 1941. Through a brief overview of the history of the Italian modern poets, the present study investigates the path followed by Vittorio Sereni during his youth, at the beginning of his literary career. Such path, as will be shown later, was of the utmost importance for the poets humanitarian, cultural and intellectual development, and includes the philosophy lectures given by Antonio Banfi at the University of Milan, the time spent as a writer at the magazine \"Corrente di vita giovanile\" and the admiration of and friendship with fellow poets Eugenio Montale, Giuseppe Ungaretti and Umberto Saba. Moreover, this research addresses the controversial debate on whether Sereni integrated or not the Italian hermetic movement in the 1930s and 40s. Lastly, through the study of four poems from the selected book, \"Inverno\", \"Inverno a Luino\". \"Strada di Zenna\" e \"Ecco le voci cadono\", recurrent central themes in Frontiera will be presented and analyzed.

Essa dissertação desenvolve e faz uso de uma técnica de medição com objetivo de obter dados experimentais envolvidos no ciclo de trabalho dos compressores herméticos alternativos, largamente utilizados nos sistemas de refrigeração. O trabalho mostra o comportamento das válvulas de admissão e descarga durante o funcionamento do compressor, as pressões no cilindro, na sucção, na descarga e também a variação de rotação do eixo durante um ciclo de compressão completo. Todas as características mensuradas estão referenciadas à posição angular do eixo do compressor, o que permitiu monitorar todos os eventos em função do seu deslocamento angular. Para o desenvolvimento desse trabalho foi necessário planejar um sistema de medição robusto, não vulnerável aos fatores ambientais, presentes dentro da carcaça do compressor. A limitação do espaço físico foi um fator de grande importância na escolha dos sensores, assim como a velocidade de resposta dos instrumentos, pois um ciclo de compressão tem período menor que 0,020 segundos. A coleta dos dados e a análise dos sinais foram realizadas com o auxilio de hardware apropriado e software especialmente desenvolvido. / In this dissertation it is developed and applied measurement methods to obtain experimental data of a hermetic compressor work cycle, widely used in the refrigeration systems. This work shows the suction and discharge valve behaviors, the pressure in the cylinder, as well as in the discharge and suction chambers, and also crankshaft rotation variation during a complete compression cycle. All the measurements are reference to crankshaft angular position of compressor which allows to verify the events as a function of the crankshaft angular displacement. For the development of this work it was necessary to plan a reliability measure system, not affected by environmental factors inside the housing of compressor. The inner space limitation was an important feature for choosing the sensors as well as their time response, since the period compression cycle is less than 0.020 seconds. The data acquisition and signal analysis were done with appropriate hardware and it was developed a specific software.

Essa tese tem o objetivo modelar um subconjunto de peças de um compressor hermético de refrigeração idealizado utilizando um programa de elementos finitos para estudar a pressão de contato na junta da placa de válvulas com e sem pressão de gás refrigerante. Nessa pesquisa também se faz a modelagem dinâmica da bomba de um compressor acadêmico com vistas a estudar a vibração gerada durante seu funcionamento. No estudo da junta de vedação se faz um modelo geométrico do conjunto cabeçote e juntas com um programa CAD. A partir da geometria do subconjunto um modelo físico é construído no ANSYS®, que leva em consideração as diferentes propriedades dos materiais do conjunto cabeçote e juntas, inclusive a não linearidade do material da junta. São feitas simulações aplicando diferentes valores de força normal nos parafusos do cabeçote. No estudo de vibração do compressor faz-se o modelo de CAD da bomba de onde se obtém seu peso e propriedades de inércia. A matriz de rigidez do sistema de suspensão da bomba é calculada e se faz a análise modal da bomba. Os resultados das análises de pressão de contato foram mostrados através de gráficos da normal closure e da normal pressure da junta. Eles indicam de forma clara as regiões de baixa pressão de contato aplicada pelas peças que estão ou deveriam estar comprimindo a junta de vedação, que seriam regiões de falhas. Na análise dinâmica da bomba do compressor, é calculada a matriz de rigidez total do sistema com as molas de suspensão, levando em consideração a rigidez compressiva, de flexão e cisalhante das molas. Com a solução do modelo dinâmico criado, calcula-se a matriz dinâmica, a matriz modal normalizada, a matriz de frequências características, o deslocamento <span style=\"font-style:italic\">X <span style=\"position: relative; bottom: 1.3ex; letter-spacing: -1.2ex; right: 1.2ex\">&#8594; da bomba e também as energias cinética e potencial da bomba devido às forças de agitação. O modelo de elementos finitos da junta da placa de válvulas tem resultados coerentes e o modelo dinâmico da bomba fornece vários resultados para a análise de vibração de compressores. / This thesis has as objective to model a subset of parts of an idealized hermetic compressor for refrigeration using a program of finite elements intended to study the contact pressure on the valve plate gasket with and without pressure from the refrigerant gas. In this research a dynamic modelling of an academic compressor pump is also made with the aim of studying the vibration generated during its functioning. In the study of the sealing gasket, a geometric model of the cylinder head and gasket assembly is made by using a CAD program. From the geometric of the subset a physical model is built on the ANSYS®, which takes into account the different properties of the cylinder head and gasket assembly materials, including the non-linearity of the gasket material. Simulations are made by applying different normal force values on the cylinder head screws. In the compressor vibration study, a CAD pump model is made, thus obtaining its weight and inertia properties. The stiffness matrix of the pump suspension system is calculated and a modal analysis of the pump is made. The results from the contact pressure analyses were shown through \"normal closure\" and \"normal pressure\" charts of the gasket. They show in clear form the low contact pressure regions applied by the parts that are or should be compressing the sealing gasket, which would the regions of failures. In the dynamic analysis of the compressor pump, the total stiffness matrix of the system is calculated with the suspension springs, taking into account the compressive, flexural and shearing rigidities of the springs. With the solution of the dynamic model created, the following are calculated: the dynamic matrix, the normalized modal matrix, the characteristics frequency matrix, the <span style=\"font-style:italic\">X <span style=\"position: relative; bottom: 1.3ex; letter-spacing: -1.2ex; right: 1.2ex\">&#8594; displacement from the pump, as well as the kinetic and potential energy of the pump due to shaking forces. The finite elements model of the valve plate gasket has coherent results and the dynamic model of the pump provides various results for the analysis of the compressor vibration.