Made available in DSpace on 2014-10-09T12:45:41Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:07:18Z (GMT). No. of bitstreams: 1 07609.pdf: 2103835 bytes, checksum: daf8a4e12257ed226478079afb3ed0d5 (MD5) / Dissertacao (Mestrado Profissionalizante em Lasers em Odontologia) / IPEN/D-MPLO / Instituto de Pesquisas Energeticas e Nucleares, IPEN/CNEN-SP; Faculdade de Odontologia, Universidade de Sao Paulo

Orientador: Yoon Kil Chang / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos / Made available in DSpace on 2018-08-12T17:17:33Z (GMT). No. of bitstreams: 1 Costa_PaulaFernandaPintoda_M.pdf: 1614314 bytes, checksum: ca5c2d3f9f5705e6eb10f0be8842c7f9 (MD5) Previous issue date: 2009 / Resumo: Existe uma demanda crescente por produtos funcionais contendo fibras, principalmente por produtos de panificação utilizando farinha de trigo integral, devido aos benefícios à saúde, como a diminuição do risco de alguns tipos de câncer, doenças cardiovasculares, diverticulites e problemas relacionados à obesidade. No entanto, a farinha de trigo integral possui vida de prateleira reduzida por apresentar alta atividade enzimática e presença de bolores e leveduras que dificultam seu armazenamento e conservação. Estudos demonstraram que a vida de prateleira da farinha de trigo integral pode ser prolongada através de métodos de estabilização, como a utilização de radiação gama ou radiação infravermelha em condições adequadas. Este trabalho objetivou estudar o efeito de métodos de estabilização da farinha de trigo integral utilizando radiação gama e radiação infravermelha na vida de prateleira e nas características tecnológicas da farinha integral e na elaboração de pão de forma. Foram realizados experimentos para estabelecer as melhores doses de radiação gama (0,5; 1,5; 2,5; 3,5 e 4,5 kGy), aplicada na farinha de trigo integral e nos grãos de trigo. As condições ideais de temperatura e tempo de exposição do farelo à radiação infravermelha, foram determinadas através do Delineamento Composto Central Rotacional (DCCR 22), variando a temperatura de 66 (-1,41) a 94ºC (+1,41), e o tempo de 8 (-1,41) a 22 minutos (+1,41). Os ensaios da radiação infravermelha foram realizados em estufa equipada com resistências infravermelhas de cerâmica, de comprimento de onda de 2,7 µm. Foram realizadas análises após a aplicação das doses de radiação gama (na farinha e no grão) e radiação infravermelha (no farelo), sendo avaliadas as características físico-químicas (composição centesimal e cor) e reológicas (viscosidade da pasta, farinografia, extensografia, teores e índices de glúten e Falling Number) das farinhas irradiadas e controle. As farinhas integrais e os grãos irradiados com radiação gama e a farinha de trigo integral reconstituída com o farelo submetido a radiação infravermelha (20 min a 90ºC) foram armazenados durante quatro meses e a cada mês foram realizadas análises para acompanhamento da estabilidade (acidez do extrato etéreo, microbiologia e presença de insetos), e desempenho em panificação (volume específico, umidade e dureza dos pães de forma integrais). Os resultados demonstraram que: a) a qualidade da farinha de trigo integral e dos pães de forma é influenciada por sua estabilidade e características reológicas; b) os efeitos da radiação gama na farinha integral são dependentes da dose de radiação gama aplicada, sendo que todas elas afetaram de modo negativo as características reológicas e a qualidade dos pães, devido a modificações causadas nas frações amido e proteína; no entanto a utilização de baixas doses melhorou a estabilidade, porém, devido aos efeitos adversos na massa, esta técnica não é recomendada; c) os efeitos da radiação gama nos grãos de trigo também são dependentes da dose utilizada; no entanto, se observou que os efeitos no grão não são tão intensos como aqueles observados na farinha de trigo integral, sendo que a dose 0,5 kGy, foi eficiente na estabilização dos grãos e da farinha resultante, não interferindo significativamente nas características reológicas e na qualidade dos pães, podendo ser uma alternativa para o prolongamento da estabilidade dos mesmos; d) a utilização de radiação infravermelha demonstrou ser eficiente nos propósitos deste trabalho, pois, prolongou a estabilidade da farinha de trigo integral e melhorou a qualidade dos pães de forma integrais. Esta depende das condições de tempo e temperatura utilizadas, sendo verificado que a exposição do farelo a 90ºC por 20 minutos foi eficiente para reduzir a atividade da enzima lipase e a contagem de bolores e leveduras, melhorando a estabilidade da farinha de trigo integral e a qualidade dos pães / Abstract: There is an increasing demand for functional products with fibers, mainly for bakery products using whole wheat flour, due to health benefits, such as reductions of the risk cardiovascular and diverticular diseases, cancer, and problems related to obesity. However, whole wheat flour has a reduced shelf life because it presents high enzymatic activity and the presence of molds and yeasts that make its storage and conservatism difficult. Studies have demonstrated that the shelf life of whole wheat flour can be improved through stabilization methods, such as gamma radiation or infra red radiation used in adequate conditions. The objective of this work was to study the effect of stabilization methods for whole wheat flour using gammaradiation and infra red radiation on the shelf life and technological characteristics of the whole wheat flour and on whole bread elaboration. Experiments were carried out to establish the best doses of gamma radiation (0.5, 1.5, 2.5, 3.5 and 4.5 kGy), applied to whole wheat flour and to wheat grains. The ideal conditions of temperature and exposition time of the bran to infra red radiation, were determined through the Response Surface Methodology (CCRD 22), varying temperature from 66 (-1,41) to 94ºC (+1,41), and time from 8 (-1,41) to 22 minutes (+1,41). The infra red radiation assays were carried out in an oven equipped with infra red ceramic resistances, with a wave length of 2.7 µm. Analyses were carried out after the application of gamma radiation doses (in the flour and in the grain) and infra red radiation (in the bran)evaluating the physical-chemical (proximate chemical composition and color) and rheological (paste viscosity, farinograph, extensograph, gluten content and Falling Number) characteristics of radiated and control flours. The gamma radiated whole wheat flours and grains and the whole wheat flour reconstituted with the bran submitted to infra red radiation (20 min at 90ºC) were stored during four months and at each month analyses to follow stability (fat acidity, microbiology and presence of insects), and to evaluate baking performance (specific volume, moisture and hardness of whole breads) were carried out. The results demonstrated that: a) the quality of whole wheat flour and of the whole breads is influenced by their stability and rheological characteristics; b) the effects of gamma radiation on whole flour are dependent on the gamma radiation dose applied, but all doses negatively affected rheological characteristics and bread quality, due to modifications caused in the starch and protein fractions; however, the use of low doses improved stability, but due to the adverse effects on the dough, this technique is not recommended; c) the effects of gamma radiation on the wheat grains are also dependent on the dose used; however, it was observed that the effects of radiation on the grains are not so intense as those observed on the whole wheat flour, being the dose of 0.5 kGy efficient in the stabilization of the grains and resultant flour, not intervening significantly with rheological characteristics and bread quality, being an alternative for increasing their stability; d) the use of infra red radiation demonstrated to be efficient for the intentions of this work; as, it increased the stability of whole wheat flour and improved bread quality. It depends on the conditions of time and temperature used, being verified that the exposure of the bran to 90ºC for 20 minutes was efficient to reduce lipase activity and yeasts and molds count, improving stability of whole wheat flour and bread quality / Mestrado / Mestre em Tecnologia de Alimentos

No atual contexto da indústria automotiva nacional e internacional, como parte do processo produtivo, no nível da Linha de Produção, são realizadas inspeções para a verificação da qualidade dos itens utilizados nos produtos destinados ao mercado consumidor. Dentre esses itens está o sistema elétrico que equipa os veículos automotores, cujo funcionamento dos circuitos deve ser inspecionado na fase final de montagem dos veículos, para a verificação do atendimento à conformidade aplicada ao sistema elétrico em questão. A partir dessa conjuntura desenvolveu-se o presente trabalho cujo conteúdo aborda proposta conceitual de aplicação da comunicação por radiação infravermelha em sistema de auxílio à inspeção da rede elétrica de veículo automotor. Essa abordagem trata de elementos do projeto conceitual de um sistema específico, cujo modelo de aplicação propõe a utilização de unidades portáteis destinadas à realização das inspeções, sendo a radiação infravermelha utilizada para comunicação sem fios, na transferência automática de dados das inspeções. Os resultados obtidos nos ensaios práticos efetuados com os protótipos dos elementos do sistema abordado foram satisfatórios, sendo validados os princípios de funcionamento desses elementos, ratificando os conceitos propostos, principalmente no que se refere: à aplicação da comunicação por radiação infravermelha; ao modelo de aplicação do sistema abordado, que utiliza unidades móveis para a realização das inspeções em questão; ao conceito de integração de sistemas, que prevê a integração do sistema abordado com os demais sistemas computacionais tipicamente existentes nas empresas produtoras de veículos automotores. Os objetivos propostos foram atingidos, sendo no conteúdo do trabalho apresentados os resultados de pesquisas voltadas para o propósito de contribuir para a evolução da tecnologia empregada em sistema de auxílio à inspeção de funcionamento de circuitos elétricos de veículos automotores. / Nowadays the national and international automotive industry, at Production Line level and as part of their productive process, perform inspections to verify the quality of items employed in products dedicated to the consumer market. Among those items is the electrical system that equips the auto motor vehicles, which must have its circuitry operation inspected in the final assembly line, in order to verify if it is complying with the requirements applied to such electrical system. Starting from such context it was developed this work whose content treats of conceptual proposal of application of communication by means of infrared radiation in system of aiding to inspection of auto motor vehicle electrical network. That approach treats of elements of conceptual design of a specific system, whose model of application proposes the utilization of portable units dedicated to the accomplishment of inspections, where the infrared radiation is employed to the wireless communication, in the automatic data transfer from inspections. The tests results with the prototypes of elements of the system aforementioned were accordingly performed. It was validated the principles of operation of those elements confirming the proposed concepts, mainly concerning to the application of infrared radiation to the proposed system, that uses portable units for accomplishment of inspections, described herein, to the concept of system integration. Such system foresees its integration with computational systems typically employed by companies that produce auto motor vehicles. The proposed goals were reached and within the context of that work the results of this research aiming to contribute to the evolution of the technology used in system of aiding to the inspection of operation of auto motor vehicles electrical networks.

Orientadores: Rafael Augustus de Oliveira, Kil Jin Park / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Agrícola / Made available in DSpace on 2018-08-25T10:54:18Z (GMT). No. of bitstreams: 1 SanchezSaenz_CarolinaMaria_D.pdf: 5939209 bytes, checksum: 43efccade58fb536d9e9c45782a43cc3 (MD5) Previous issue date: 2014 / Resumo: As pesquisas atuais em secagem de alimentos levam em consideração a qualidade do produto e a eficiência energética do processo, já que este processo consome cerca de 20-25% da energia utilizada pelo processamento na indústria de alimentos. Isto faz com que sejam exploradas novas técnicas e combinações de métodos de secagem e avaliação da intermitência do processo. Assim, realizou-se mais um estudo com o secador agitador/misturador (patente PI 0506639-5), iniciando pela adequação das pás do eixo misturador e adaptação do sistema de controle de velocidade e aquecimento do ar. O tempo de residência foi determinado considerando a rotação do eixo das pás e a rotação do eixo de alimentação do secador. Foi avaliada a influência dos parâmetros de secagem sobre o processo, de modo que foi possível determinar as melhores condições de pré-secagem HTST (High Temperature and Short Time) combinada com a secagem convectiva contínua com aplicação de radiação infravermelha, para obtenção de um produto de qualidade e com baixa demanda de energia elétrica no processo. Foi feito também o estudo da influência desses processos nas propriedades físicas e mecânicas de raízes de chicória. A redução da demanda de energia elétrica foi obtida considerando a intermitência da aplicação de radiação infravermelha. Os testes e análises realizados nestas condições resultaram em uma série de dados que garantem que a combinação de métodos de secagem e de técnicas de intermitência são eficientes energeticamente e resultam em um produto de boa qualidade / Abstract: In recent research works, food drying takes into account product quality and energy efficiency of process, since drying process consumes about 20-25 % of the energy used by the food processing industry. This fact indicates that new techniques combining drying methods and intermittency of the process must be evaluated. Thus, a study with the agitator / mixer dryer (patent PI 0506639-5) was performed, beginning with the mixer blades adequacy and velocity control and air heating systems adaptation. Residence time distribution determination has been conducted, considering rotation of blades and feed rotation of dryer. The influence of dying parameters on the process was evaluated, so that it was possible to determine the best conditions of HTST (High Temperature and Short Time) drying combined with the continuous drying with pulse of infrared radiation application, to obtain a good quality dried product and electric energy efficiency of the process. Study the influence of these processes was also done on the physical and mechanical properties of chicory roots. Finally, the electric energy efficiency was obtained considering the intermittency of pulse infrared radiation application. The experimental runs and analyses under these conditions have generated data which ensure that the combination of drying methods and intermittency techniques are energy efficient and result in a good quality product / Doutorado / Tecnologia Pós-Colheita / Doutora em Engenharia

No description available.

The main theme of the master's thesis is using of thermal camera to measure temperatures in electrical engineering. First are mentioned the physical principles of heat transfer. Then the thesis deals with methods of determining the correct emissivity of the measured object and in the next point with sensors designed for sensing infrared radiation, there is also part dedicated to evaluation software Report Sat Standard, which was used to evaluate the pictures taken with thermal camera SAT-HY 6800. Next part of this work is the measurement of the DC and EC motor with help of thermocamera, which took place in the electric company ATAS Nachod. Attachment to this master's thesis there is animation of EC motor created in Autodesk Inventor.

Cette thèse, de nature expérimentale, rentre dans le cadre de la récupération d’énergie pour les micro-générateurs et l’autonomie des dispositifs électroniques à faible consommation. Ce travail propose les possibilités de récupérer de l’énergie thermique par effet pyroélectrique. L’éner- gie thermique à convertir est une variation temporelle de température. Nous avons proposé deux principales techniques pour produire de l’énergie électrique via une céramique pyroélectrique de type PZT. La première est centrée sur la récupération des radiations infrarouges associé à la tech- nique SSHI. Originellement, la technique SSHI a été développée dans le cas de la récupération d’énergie piézoélectrique, mais nous l’avons appliqué dans le cas de la pyroélectricité et qui nous a permis de maximiser la puissance récupérée d’un facteur de 2. La seconde technique proposée concerne la récupération des fluctuations thermiques provenant des mouvements convectifs nais- sant à l’intérieur d’un fluide dans la configuration de Rayleigh-Bénard. Nous avons mené plusieurs études pour augmenter le transfert convectif dans le but d’améliorer la réponse pyroélectrique et donc maximiser la puissance récupérée. Dans le cas des convections naturelles, le choix de fluide adéquat et l’optimisation des paramètres de contrôle de la configuration Rayleigh-Bénard consti- tuent des étapes primordiales pour aboutir à un meilleur transfert thermique par convection. Dans le cas des convections forcée, il a été étudié l’intérêt de disperser des particules de Cuivre de taille nanométrique dans un fluide porteur pour augmenter plus davantage le transfert convectif. Avec ce nanofluide, la réponse pyroélectrique a été maximisée d’un facteur de 10. / This experimental thesis focuses on the energy harvesting for micro-generators and au- tonomy of electronic devices with low consumption. This work proposes the possibilities of har- vesting thermal energy by pyroelectric effect. The thermal energy to be converted is thermal fluc- tuations. We proposed two main techniques to generate electricity by pyroelectric ceramic. The first one focuses on the harvesting of infrared radiation associated with the SSHI technique. Ori- ginally, the SSHI technique was developed in the case of the piezoelectric energy harvesting, but we applied it in the case of pyroelectricity and which allowed us to maximize the harvested power by a factor of 2. The second proposed technique concerns the harvesting of thermal fluctuations resulting from convective movements originating inside a fluid in the Rayleigh-Bernard configu- ration. We have carried out several studies to increase the convective transfer in order to improve the pyroelectricresponse and maximize the harvested power. In the case of natural convection, the choice of a suitable fluid and the optimization of the control parameters of the Rayleigh-Bernard configuration are essential steps in order to achieve better heat transfer by convection. In the case of forced convection, it has been studied the advantage of dispersing copper nanoparticles in a pure fluid to increase the convective transfer. With this nanofluid, the pyroelectric response was maximized by a factor of 10.

Encore jamais été observé, le rayonnement infrarouge moyen et lointain consécutif aux sprites a été prédit et serait lié à l’excitation des états vibrationnels de CO2. En sciences de l’atmosphère, la composition chimique peut être retrouvée par des méthodes de télédétection infrarouge. Pour la Défense, les émissions infrarouges naturelles peuvent causer de fausses alarmes à travers les systèmes de veille optronique satellitaires ou aéroportés. C’est pourquoi il est nécessaire de caractériser les émissions infrarouges des sprites. Pour cela, un modèle de cinétique plasma-vibrationnelle a été développé et couplé à un modèle de transfert radiatif atmosphérique. Celui-ci permet de simuler les effets énergétiques et chimiques consécutifs à la perturbation électrique des streamers, éléments constitutifs des sprites. Les signatures infrarouges évaluées devraient être détectables pour un observateur situé dans la stratosphère ou dans l’espace. Par ailleurs, les effets des incertitudes sur les principaux paramètres du modèle ont été quantifiés à travers une étude de sensibilité. Enfin, ces travaux ont permis de définir certaines spécifications instrumentales pour la mission HALESIS (High Altitude Luminous Events Studied by Infrared Spectro-imagery), qui aura pour but d’observer les sprites et autres phénomènes lumineux de moyenne atmosphère dans l’infrarouge. / Even if it hasn’t been observed yet, the existence of emissions in the middle and far infrared following a sprite is suspected and could be related to vibrational excitation of CO2. In atmospheric sciences, the chemical composition can be retrieved through different remote sensing methods. For the Defense, natural infrared emissions could cause false alarms through airborne and spaceborne optronic detection systems. That is why it is necessary to characterize the infrared emissions of sprites. To do so, a plasma-vibrational kinetic model has been developed and coupled to an atmospheric radiative transfer model. This model allows evaluating the energetic and chemical effects following the electrical perturbation caused by the propagation of streamers, main constituent elements of sprites. The evaluated signatures could be detectable for an observer situated in the stratosphere or in space. Otherwise, the effects of the uncertainties on the principal parameters of the model have been quantified through a sensitivity analysis. Finally, this work allowed defining instrumental specifications for the future mission HALESIS (High Altitude Luminous Events Studied by Infrared Spectro-imagery), which will record hyperspectral infrared images of sprites and other middle atmosphere luminous events.

An investigation of the high spectral resolution signatures and radiative forcing of tropospheric aerosol in the thermal infrared was conducted. To do so and to support advanced modeling of optical properties, a high spectral resolution library of atmospheric aerosol optical constants was developed. This library includes new optical constants of sulfate-nitrate-ammonium aqueous solutions and the collection of a broad range of existing optical constants for aerosol components, particularly mineral optical constants. The mineral optical constants were used to model and study infrared dust optical signatures as a function of composition, size, shape and mixing state. In particular, spherical and non-spherical optical models of dust particles were examined and compared to high spectral resolution laboratory extinction measurements. Then the performance of some of the most common effective medium approximations for internal mixtures was examined by modeling the optical constants of the newly determined sulfate-nitrate-ammonium mixtures. The optical signature analysis was applied to airborne and satellite high spectral resolution thermal infrared radiance data impacted by Saharan dust events. A new technique to retrieve dust microphysical properties from the dust spectral signature was developed and compared to a standard technique. The microphysics retrieved from this new technique and from a standard technique were then used to investigate the effects of dust on radiative forcing and cooling rates in the thermal IR.

Made available in DSpace on 2014-10-09T12:48:08Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:07:31Z (GMT). No. of bitstreams: 1 09302.pdf: 3407854 bytes, checksum: 9ad0354f272b3e3c59f9432ff90a5c98 (MD5) / Tese (Doutoramento) / IPEN/T / Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP