Submitted by Cássia Santos (cassia.bcufg@gmail.com) on 2017-03-13T16:38:28Z No. of bitstreams: 2 Dissertação - Kamilla Soares Silva - 2017.pdf: 3492036 bytes, checksum: dc2e1dccbf2920f944a35cd9546e6852 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2017-03-20T12:16:53Z (GMT) No. of bitstreams: 2 Dissertação - Kamilla Soares Silva - 2017.pdf: 3492036 bytes, checksum: dc2e1dccbf2920f944a35cd9546e6852 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2017-03-20T12:16:54Z (GMT). No. of bitstreams: 2 Dissertação - Kamilla Soares Silva - 2017.pdf: 3492036 bytes, checksum: dc2e1dccbf2920f944a35cd9546e6852 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2017-02-23 / Fundação de Amparo à Pesquisa do Estado de Goiás - FAPEG / To elaborate a better combination of Brazil nut (Bertholletia excelsa) and Baru (Dipteryx alata Vogel) in the development of the mixed water-soluble extract, with good physicochemical, physical and biological stability, a simplex centroid type mixture delineation was performed, a mixture between Brazil nut, Baru almond and water. The Brazil nut and Baru almond water-soluble extract obtained was packed in 220 mL glass bottles and pasteurized in stainless steel casing, then cooled and stored under refrigeration (4 degrees) until the physicochemical, physical, microbiological and sensory determinations. The determinations were performed in triplicate and the results were analyzed by the Statistica software and the mathematical models were generated, tested and validated. In order to obtain a better acceptance of the beverage, in both most accepted extracts in the sensorial analysis a fixed amount of 10,00% (w/v) sugar was added and the amount of preservatives for the reduction of residual taste, reduced. After the definition of the best mixture formulation, determined by global acceptance and purchase intention parameters, the water-soluble extract with the best grade was reprocessed in large scale and stored during 28 days, under 4 degrees refrigeration, evaluating the rheological profile and keeping up with the evolution of physicochemical, microbiological and sensorial analysis parameters. The formulation of water-soluble extract composed by 69.17% (w/w) of water, 9.17% (w/w) of Brazil nut and 21.67% of 10,00% (w/v) sucrose Baru almond was the favorite in the global acceptance test. The mathematical models obtained by the simplex centroid planning achieved better adjustments with the special cubic model proving to be highly predictive. The water-soluble extract presented non-newtonian pseudoplastic fluid behavior. The microbiological determinations did not demonstrate contamination of the beverage over the refrigerated storage time, indicating adequate hygienic handling during the processing and its good biological stability. / Com o objetivo de elaborar a melhor combinação entre amêndoas da Castanha-do-Brasil (Bertholletia excelsa) e Baru (Dipteryx alata Vogel) para o desenvolvimento de um extrato hidrossolúvel misto, com estabilidade físico-química, física e biológica, realizou-se um delineamento de misturas do tipo simplex-centroide, sendo uma mistura ternária entre as amêndoas e Água. O extrato hidrossolúvel a base de Castanha- do-Brasil e Baru obtido foi envasado em garrafas de vidro de 220 mL e pasteurizado em tacho encamisado de aço inoxidável, sendo posteriormente resfriados e estocados a 4 °C até o momento da realização das determinações físico-químicas, físicas, microbiológicas e sensoriais. Tais determinações foram realizadas em triplicata e os resultados analisados geraram modelos matemáticos que puderam ser testados e validados. Com o intuito de obter uma melhor aceitação da bebida, nos dois extratos hidrossolúveis mais aceitos nas análises sensoriais, foram adicionados uma quantidade fixa de açúcar de 10,00% p/v, expressos em sacarose, e reduzidos a quantidade de conservantes para a diminuição do sabor residual. Após estabelecida a melhor formulação da mistura, determinada através da aceitação global e intenção de compra, o extrato hidrossolúvel com a melhor nota foi novamente processado e armazenado durante 28 dias, sob refrigeração a 4° C, para acompanhamento da estabilidade através de parâmetros físico-químicos, microbiológicos, sensoriais e perfil reológico. A formulação de extrato hidrossolúvel composta por 69,17% (p/p) de água, 9,17% (p/p) de Castanha-do-Brasil e 21,67% (p/p) de Baru, adicionado de 10,00% (p/v) de açúcar, expressos em sacarose, foi a preferida no teste de aceitação global. Os modelos matemáticos obtidos pelo planejamento simplex-centroide apresentaram bons ajustes aos dados experimentais. O extrato hidrossolúvel apresentou comportamento de fluido não-newtoniano pseudoplástico. As determinações microbiológicas não demonstraram contaminação da bebida ao longo do tempo de armazenamento refrigerado, indicando manipulação higiênica adequada durante os processamentos e sua boa estabilidade biológica.

No presente trabalho, diferentes condições de pasteurização foram estudadas a fim de desenvolver um purê de manga para pronto consumo, sem adição de açúcares e de conservantes, com estabilidade microbiológica, físico-química e sensorial. A qualidade e a vida de prateleira do purê foram avaliadas por meio de análises físico-químicas, microbiológicas, enzimáticas, reológicas e sensoriais. Na primeira etapa do trabalho, foram estudadas temperaturas de pasteurização entre 65 e 85 °C, em trocador de calor a placas e tubular. Os ensaios mostraram que o trocador tubular foi o mais indicado para a pasteurização do purê de manga. A inativação térmica da peroxidase, uma das enzimas mais termorresistentes encontradas naturalmente em mangas, foi utilizada como parâmetro de pasteurização. Os parâmetros cinéticos para inativação da enzima foram calculados: D77,2 ºC e z iguais a 4,4 s e 14,3 ºC, respectivamente. Na segunda etapa, duas condições de pasteurização, P1 (70ºC/13s) e P2 (75 ºC/13s), foram selecionadas para determinação da vida de prateleira do purê. A pasteurização nestas condições, combinada ao armazenamento refrigerado, foi eficiente para manter a qualidade microbiológica, físico-química e sensorial do purê por 17 semanas. Análises microbiológicas indicaram que os maiores contaminantes do purê cru foram os microrganismos mesófilos e os bolores e leveduras. Com a pasteurização, houve redução significativa destes microrganismos e de coliformes fecais. Todas as características físico-químicas (pH, acidez titulável, teor de sólidos totais, sólidos solúveis, ácido ascórbico e cor) foram influenciadas significativamente pelo tempo de armazenamento. Foi observada diferença significativa do pH a partir da 17ª semana de armazenamento e a perda de ácido ascórbico foi de aproximadamente 45 % após 20 semanas. As medidas reológicas mostraram a natureza pseudoplástica do purê de manga: os valores de n variaram entre 0,27 e 0,29 e os valores de K entre 5,00 e 7,16 Pa.sn. O tempo de armazenamento praticamente não influenciou os parâmetros reológicos dos purês pasteurizados. Na análise sensorial, notas superiores a 6,7 foram obtidas, indicando que o produto teve boa aceitação durante as 17 semanas de armazenamento. O tempo de armazenamento não influenciou significativamente os atributos sensoriais, exceto no purê processado na condição P1. / In this work, different pasteurization conditions were studied in order to develop a ready-to-serve mango purée, with microbiological safety and physical-chemical and sensorial stability. Physical-chemical, microbiological, enzymatic and sensory analyses and rheological measurements were carried out to evaluate quality and shelf life of mango purée. Two types of heat exchanger were used to pasteurize mango purée: a plate heat exchanger and a double pipe heat exchanger. Pasteurization temperatures ranged from 65 to 85ºC. The double pipe exchanger showed to be more suitable for the process, due to characteristics of purée. Thermal inactivation of peroxidase, one of most thermostable enzymes naturally present in mangoes, was used as indicator of pasteurization. Kinetic parameters were calculated: D77.2 ºC = 4.4 s and z = 14.3 ºC. Two pasteurization conditions P1 (70 °C / 13s) and P2 (75 °C / 13s) were selected in order to determine shelf life of mango purée. Pasteurization, combined to refrigerated storage, was effective to maintain microbiological, physical, chemical and sensory quality of purée for 17 weeks. Microbiological analysis showed that the main contaminants of raw purée were mesophilic microorganisms and yeast and moulds. After pasteurization, there was significant reduction of these microorganisms and of thermo-tolerant coliforms. All physical-chemical attributes (pH, titratable acidity, total solids, soluble solids, ascorbic acid and color) were affected significantly by storage time. It was observed significant difference in pH after 17 weeks of storage and ascorbic acid loss was approximately 45 % after 20 weeks. Rheological measurements showed shear thinning nature of mango purée: n values varied from 0.27 to 0.29 and K values from 5.00 to 7.16 Pa.sn. Storage time did not affect significantly rheological parameters of pasteurized purées. Sensory analysis of pasteurized mango purée indicated that the product has good acceptance (scores \'> or =\' 6,7) over 17 weeks of refrigerated storage. Storage time did not affect significantly sensory attributes, except color of P1 mango purée.

Au cours du traitement thermique rapide (RTP) des cellules photovoltaïques à couches minces, un suivi du profil de température souhaité et une homogénéité de la chauffe substrat doivent être assurés. Le but de cette thèse est de proposer une méthodologie de conception d'un four RTP permettant d'atteindre la qualité du cycle de la chauffe souhaitée.Une modélisation thermique est réalisée en se basant sur la méthode de réseaux de composants afin de prédire le comportement thermique dynamique du four. L'approximation des flux plans et l'approximation des couches minces semi-transparentes sont utilisées pour le calcul des facteurs d'échanges directs. L'algorithme des revêtements est appliqué pour en déduire les facteurs de transfert. Le modèle thermique développé est validé expérimentalement sur un four de petites dimensions. Une méthodologie de conception du four RTP est proposée en tenant compte de l'aspect dynamique des conditions thermiques du four. Une optimisation par algorithme génétique est effectuée pour trouver l'emplacement des émetteurs. Pour chacune des configurations testées, la distribution de la puissance aux émetteurs à fournir à chaque instant est optimisée par programmation dynamique. Finalement, cette méthodologie est appliquée pour la conception d'un four RTP pour le traitement de cellules photovoltaïques à couches minces de 30 × 60 cm2. Les résultats des essais confirment la validité de la méthodologie proposée. / During the rapid thermal processing (RTP) of thin film photovoltaic cells, the temperature of the latter has to follow a preset time evolution profile, while keeping spatial uniformity of the wafer. The aim of this study is to propose a design methodology of RTP furnace in order to obtain the quality of the required heating cycle.A thermal modeling is performed based on the component interaction network approach to predict the thermal behavior of the furnace. Flux plane approximation and semi-transparent thin layer approximation are used to calculate the direct exchange factor. The plating algorithm is then applied to calculate the transfer factor. The thermal model developed is validated experimentally on a furnace of small dimensions. A methodology to design a RTP furnace is proposed taking into account the dynamic aspect of the thermal conditions of the furnace. An optimization using the genetic algorithm is performed in order to find emitter dispositions. For each tested configuration, the optimal input power distribution over the emitters at each time step is found by using real time dynamic programming. Finally, the methodology is applied for the design of RTP furnace for the heat treatment of thin film photovoltaic cells of 30 × 60 cm2. Test results confirm the validity of the methodology proposed.

This work studied the improvement of stability, physical properties and enzymatic inactivation in fruit beverages by applying the ultrasound technology (US). In the first part, the effect of the US application on peach juice processing was evaluated. The macroscopic changes on pulp sedimentation stability, turbidity, colour and rheological properties were evaluated. As a result, it was demonstrated that the improvement in each of the properties evidenced at the macroscopic level involves interaction of complex mechanisms which depend directly on changes at the microscopic level, such as the structure, size, composition and interaction between the continuous phase (serum) and dispersed phase (pulp) of the juice. These changes were assessed by microscopy and particle size distribution. In the second and third parts, the inactivation of the enzyme peroxidase (POD) was evaluated in coconut water. In the second part, the effect of the application of US was evaluated for first time for coconut water POD, using two types of ultrasonic equipment (US baht and US probe). It was demonstrated that the changes of enzyme activity during the US process depend on the many forms that the enzyme can adopt, mainly depending on the energy applied to the system. Subsequently, in the third part, the US was applied as a pre-treatment of subsequent thermal processing. The evaluation was carried out under non isothermal conditions, being the POD inactivation kinetics modelled using the Weibull distribution function. Finally, it was observed that the pre-treatment using ultrasound slightly decreased the enzyme activity. Furthermore, the ultrasound effects resulted in a more homogeneous population and heat-sensitive enzymes, significantly reducing the needed time of thermal processing. In conclusion, this work studied and demonstrated that the ultrasound technology is an interesting alternative to improve the physical properties and enzymatic stability in fruit beverages, reflecting the importance from both the academic and industrial point of view. / Neste trabalho estudou-se a melhoria na estabilidade, propriedades físicas e inativação enzimática em bebidas de frutas através da aplicação da tecnologia de ultrassom (US). Na primeira parte, foi avaliado o efeito do US no processamento de suco de pêssego. As alterações macroscópicas na estabilidade de sedimentação da polpa, turbidez, cor e propriedades reológicas foram analisadas. Foi demonstrado que a melhoria em cada uma das propriedades evidenciadas macroscopicamente envolve interação de mecanismos complexos que dependem diretamente de alterações microscópicas, tais como estrutura, tamanho, composição e interação entre as fases contínua (soro) e dispersa (polpa) do suco. Estas alterações foram avaliadas por microscopia e análise de distribuição de tamanho de partículas. Na segunda e terceira partes, a inativação da enzima peroxidase (POD) foi avaliada em água de coco. O efeito da aplicação do US na POD de água de coco foi estudado pela primeira vez, utilizando dois tipos de equipamentos (banho e sonda de US). Demonstrou-se que as alterações na atividade enzimática durante o processamento com US estão relacionadas às diferentes conformações que a enzima pode adotar, dependendo principalmente da energia aplicada ao sistema. Na terceira parte, o ultrassom foi então aplicado como pré-tratamento ao processamento térmico. A avaliação foi realizada sob condições não isotérmicas, sendo a cinética de inativação da POD modelada usando a função de distribuição de Weibull. Foi observado que o pré-tratamento com US diminuiu a atividade enzimática. Além disso, o efeito do US resultou em uma população de enzimas mais homogênea e termosensível, reduzindo significativamente o tempo necessário para o processamento térmico. Desta forma, este trabalho estudou e demonstrou que a tecnologia de ultrassom é uma alternativa interessante para melhorar as propriedades físicas e a estabilidade enzimática de bebidas à base de frutas, indicando sua importância tanto acadêmica quanto industrial.

Solární články na bázi arsenidu gallia patří mezi nejvýkonější typ dostupných solárních článků vůbec. Jejich výhodou je výborná odolnost vůči tepelnému a ionizujícímu záření, a proto se využívají zejména v náročných podmínkách. Tato disertační práce popisuje stav GaAs fotovoltaických článku vystavených vůči tepelnému namáhání, vysokému ochlazování, gama záření a ozáření širokospektrálním laserem. Vzorky byly zkoumány před, po a i během těchto procesů pomocí několika analytických a charakterizačních metod. Měření bylo zaměřeno na charakterizaci povrchu, optických a elektrických vlastností. Byly objeveny limity a nové chování tohoto typu článků, které jsou ovlivněny i tenkými ochrannými a antireflexními vrstvami.

The main subject of this study is the improvement of predicative ability of previously developed mathematical model for prediction of so-called “fouling critical velocity”. Attention is devoted especially to the flue gas side fouling process on active heat transfer surfaces in tubular heat exchange tube banks installed in waste incineration process plants and also a technical – economic analysis based on obtained results. The model improvement consists among others in taking into account another forces (electrostatic, capillary etc.) haven't yet been considered, which influence the mutual contact between flue gas particles in case of sedimentation fouling or the contact between particles and heat exchanger tube walls respectively. The improved model has therefore more predicative ability to the reality of fouling process. The results are used for technical – economic analysis, which determines an optimal heat exchanger design with respect to fouling. Furthermore, the algorithm of this analysis, essential fouling mechanisms, fouled heat exchanger surface cleaning methods as well as fundamental knowledge of fouling coefficient prediction are presented, whereas the emphasis is placed on industrial tubular heat exchange equipment installed in waste incineration process plants.

Thermal processing of wastes is a metod, when during combustion occur reduction of wastes till 10% previous volume. The main advantage of this method is possibility to heat utilization for heat and electric production. Through thermic process develops range of pollutants (NOx, CO, SO2, HCl, HF, PCDD/F) that had to be remove from off-gas or reduced to enviromental values in agreement with laws in force [16]. For this purpose are combustion units equip with range of devices for removing this pollutans. The main task of this diploma thesis is selectoin of ctirical device in term of pressure drops. The value of pressure drop stands significant part in proposition of efficiecy off-gas fan. In increase or decrease total pressure drop consumption of electrical energy of off-gas fan is rising or going down. Change of consumption in total classification is projecting in energy utilization rate of waste where is determinate if it stands of energy utilizatoin or just incineration. In first part of diploma thesis are described in detail availability methods of off-gas cleaning where is described their principle, advanteges, disadvatages and comparison of effectivity. In second part of diploma thesis is made example model about influnce technology on value of total pressure drop. There were chosen two technologies for removing dioxins (technology of catalytic filtration REMEDIA and DeNox/DeDiox). For both technologies were made detailed analysis of pressure drops single components of these technologies. Attainment results were compared and rated with one another. For analysis these two methods were designed mathematical process in software Maple 9.5.

The waste production and especially biodegradable waste is following mankind since the beginning of his existence. This thesis deals with a description and dividing of current available waste process technologies, including description of their advantages and disadvantages. The work is also focused on the more detailed description of the composting technology, its control and opportunities to influence on resulting parameters of compost product. The information about technical description of workplace equipments, including industrial and technological processes was provided by the company VIA ALTA from their compost plant in Blansko.

The aim of this thesis is ball screw service life measurement. Text is divided on two major parts, theoretical one and practical one. Theoretical part describes three basic methods of ball screws manufacturing – rolling, whirling and grinding. Subsequently, methods of heat treatment (inductive and laser hardening) are mentioned. Practical part is devoted to ball screw service life testing and evaluation of results. Tests were carried out on two sets of two ball screws. First set was manufactured by whirling and grinding followed by inductive hardening. Second set was manufactured by grinding followed by inductive hardening in one case and laser hardening in the second one. Test results were evaluated according to international standards.

Peanut, a major allergenic food, has life-threatening potential and is difficult to be totally avoided due to its common use in processed foods. Thermal processing can influence the allergenic properties of peanuts. However, the kinetics of the reactions caused by thermal processing has not been characterized. In our study, kinetics of the commonly used thermal processing methods on a commercial peanut cultivar (Virginia) using five time intervals was conducted. Water-soluble and SDS-sample buffer soluble proteins were extracted sequentially, and analyzed by sodium-dodecyl-sulfate polyacrylamide gel electrophoresis (SDS-PAGE) and western-blot using human plasma containing IgE antibodies. The relationships between thermal processing (time) and log transformed water-soluble/total extractable major allergen content could be explained by a simple linear regression kinetic model for most of the processing methods (except high-pressure steaming). Among all the methods with optimal processing point, frying for 6 min had relatively lower IgE binding (linear epitopes) ratio may be due to the fact that this processing condition causing break down, cross-linking and aggregation of Ara h 2, and relatively lower solubility. Besides thermal processing, enzymatic processing also is considered to be an effective method in the allergenicity of peanuts. Eleven peanut lines (Coded MS-1~MS-11, MS-9 is the check and a common cultivar namely Valencia) were pre-screened from 122 peanut lines harvested in 2015 for allergen levels. These pre-screened lines were re-planted in 2016 for further analysis. One line, MS-7, was selected for lower Ara h 1 (8.5-9.5% of total protein) and Ara h 2 (4.2-6.6% of total protein) content in 2015 and 2016. Roasted MS-9 (check) peanut powders were used for enzymatic treatment for enzyme selection. A first order kinetic reaction model was conducted to describe the relationship between enzyme concentration (0-400AzU/g) and IgE-binding property reduction. Among eight food-grade enzymes, bromelain, papain and ficin hydrolysates had lower IgE-binding properties in terms of high IgE-binding property reducing rate (K, ≥ 0.4) and were selected for the following study. MS-7 (selected) & MS-9 (at level of 200AzU/g) hydrolyzed by three selected enzymes (200AzU/g) were used for IgE binding property comparison, TGase crosslinking and functional properties study. After hydrolyzed by the selected enzymes (200 AzU/g), the emulsion and foaming stabilities were decreased. Emulsion and foaming stabilities were increased in TGase (5U/g protein) crosslinked hydrolysates, which were even higher than soy protein isolate (SPI). The IgE-binding properties of TGase treated hydrolysates were similar to the hydrolysates without TGase treatment. MS-7 hydrolysates (with/without TGase) possessed less IgE-binding properties and similar functionality as compared with MS-9 hydrolysates.