Submitted by (edna.saturno@ufrpe.br) on 2016-05-23T16:51:55Z No. of bitstreams: 1 Elias dos Santos Silva.pdf: 1558895 bytes, checksum: c0b1fc0c63835d976cb586f9f75208ea (MD5) / Made available in DSpace on 2016-05-23T16:51:55Z (GMT). No. of bitstreams: 1 Elias dos Santos Silva.pdf: 1558895 bytes, checksum: c0b1fc0c63835d976cb586f9f75208ea (MD5) Previous issue date: 2009-03-09 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / The grape growing, a great labor absorber, is also one ofthe most advanced sectors of the irrigated agriculture present in the São Francisco Valley, both under technological point-of-viewand legal working aspecto In the world, São Francisco yalley is the only wine producing zone in half-barren tropical condition. In this region, and under irrigation conditions, the grapevines harvests (Vinifera Vitis) can be programmed for different times of the year, and the wineries and the specialists in wines process foaming, white and red wines that are original, fine and of quality. There is a grouo of local institutions that develop and spreads out technologies adequated to the wines industry, and also the purchase oftechnologies from other regions ofthe country which suffer adaptations in order to attend the demands of these industries. This research aimed to analyze which forms the local technological innovations contributed for the development and launching of the foaming wine through the wine industry located in São Francisco Valley, answering the following question: "Which is the role the local technological innovation play in the foaming wine industry in São Francisco Valley?" The study was developed with multiple cases, because they involve six wine industries. The questions directed to the managers in order to promote a better understanding of how technological innovation process happens in the managemental vision. From the comparison of the obtained results and the multiple cases studies, it was searched to recognize behavior standards directed to the managemental innovation. All the cases had something in common that was the use of local technological innovations in the production of foaming wines. It was concluded, therefore, that the role the technological innovation plays in the new products development, specially the foaming wine, is in the sprouting of new specific grapes varieties for São Francisco Valley typical edafoclimatics conditions. The industries aim at reaching the northeast consumers, once the consumption of their products is restricted to festive times. It could also be detached the exploitation of the discarding grapes, the labor qualification, and the increasing offer of financia! resources destined to the region by the companies of research and development promotion. / A viticultura, grande absorvedora de mão-de-obra, é também um dos setores mais avançados da agricultura irrigada presente no Vale do São Francisco, tanto do ponto de vista tecnológico, como também sob o aspecto trabalhista No mundo, o Vale do São Francisco é a única zona produtora de vinho em condição tropical semi-árida Nesta região, e em condições irrigadas, as safras das videiras (Vitis v.inifera) podem ser programadas para diferentes épocas do ano, onde vinícolas e enólogos processam vinhos espumantes, brancos e tintos que são originais, fmos e de qualidade. Existe um conjunto de instituições locais que desenvolve e difunde tecnologias adaptadas à indústria de vinhos e, também, a compra de tecnologias de outras regiões do país, as quais sofrem adaptações a fim de atender a demandas dessas indústrias. Esta pesquisa teve como objetivo analisar de que forma as inovações tecnológicas contribuíram para o desenvolvimento do vinho espumante através da indústria de vinho localizada no vale do São Francisco, respondendo a seguinte questão: Em quais setores da vitivinicultura a inovação tecnológica tem contribuído com mais ênfase? o estudo foi desenvolvido com múltiplos casos, pois envolvem seis indústrias de vinhos. As perguntas foram direcionadas aos gestores com intuito de promover um melhor entendimento de como acontece o processo de inovação tecnológica na visão gerencial. A partir da comparação dos resultados obtidos e dos múltiplos estudos de casos, buscou-se reconhecer padrões de comportamento voltados à inovação tecnológica. Todos os casos tinham algo em comum que era o uso de inovações tecnológicas na produção de vinhos espumante. Concluiu-se, portanto, que a contribuição da inovação tecnológica no desenvolvimento de novos produtos, em especial o vinho espumante, tem maior ênfase no setor agrícola. Muitos insumos para a produção da uva são obtidos no local bem como os clones de cultivares melhorado para as condições do VSF. Pode-se destacar também o aproveitamento das uvas de descarte, a qualificação da mão-de-obra local e a crescente oferta de recursos financeiros destinados à região pelas empresas de fomento para pesquisa e desenvolvimento.

At Kiviks Musteri AB, situated in the southeast part of Scania, a wide variety of products based on fruits and berries, are produced. One of these products is base apple wine, which is used for the production of cider and mulled wine and also is sold to other producers of cider. A foaming problem has occurred at some customers when the cider is bottled, and this problem has been traced to the base wine. The aim of this paper is to investigate what causes the foaming and how the foaming is affected by the clarifying agents used during the production of the wine. An investigation whether silica based antifoaming agents might be a solution of the problem will be performed. During the work fermentations, clarification and foaming tests will be performed in laboratory scale in Kivik. Tests with four different silica based antifoaming compounds are carried out and on these samples the surface tension and viscosity are measured to see how these factors correlate with the foaming when antifoaming agents are added to the wine. What is more, fermentations with a new yeast type and fermentations with less fruit are made to investigate if this could give better foaming properties in the wine. The tests showed that it is probably proteins that are the main cause of the foaming, but an increase of the amount of bentonite, the clarifying agent reducing protein content in the wine, is not possible since this causes too much sediment. Antifoaming agents gave reduced foaming times, which were at an acceptable level, but when the wine was mixed to cider base and filtered the effect was lost. No significant differences were observed between the four antifoaming compounds. The test with the new yeast type gave no positive results when it came to foaming. The test with less fruit showed a decrease in foaming but not sufficient enough.

Les mousses rencontrées dans l’industrie pétrolière comptent parmi les mousses les plus complexes et problématiques. Lors de la production du pétrole brut, la présence de mousses stables peut entraîner de gros problèmes dans les équipements de traitement en surface à cause de la dépressurisation et de la nucléation de bulles provenant du gaz naturellement dissous dans le fluide de réservoir. Cette mousse peut rapidement occuper la moitié du volume des séparateurs et provoquer des dommages opérationnels graves, liés à des difficultés de contrôle des niveaux, à l’entraînement de liquide dans la ligne gaz et à l’entraînement de gaz dans la ligne liquide. Le contrôle de ces mousses pétrolières constitue donc un véritable enjeu, et les diverses solutions proposées sont basées sur l’utilisation de moyens physiques (chauffage, utilisation d’internes spécifiques) mais surtout sur l’utilisation d’additifs antimousses ou démoussants et plus particulièrement de silicones PDMS. Cependant, il n’existe pas encore d’optimisation possible de ces traitements du fait du manque d’études détaillées sur le comportement de ces systèmes complexes. L’objectif principal de ce travail a donc été de contribuer à la compréhension des mécanismes de formation, de stabilisation et de rupture des mousses non aqueuses et plus particulièrement des mousses de pétrole brut. Dans un premier temps, nous avons développé une nouvelle méthodologie expérimentale permettant de former des mousses représentatives des mousses pétrolières afin de comparer quantitativement différents systèmes moussants à base de pétroles bruts ainsi que l’efficacité de différentes familles d’additifs chimiques. Ensuite, nous avons étudié les cinétiques de cassage et développé un modèle de type sigmoïde permettant de décrire les courbes expérimentales de manière satisfaisante, et ouvrant la voie à une analyse quantitative de ces systèmes. Grâce à ce type de modélisation, il est possible de comparer l’efficacité des additifs chimiques en tant que démoussants et/ou antimousses et donc d’optimiser le choix du meilleur additif requis.Enfin ces développements permettent de proposer une première analyse de l’influence des caractéristiques physico chimiques de ces systèmes complexes sur leurs propriétés de moussage. / Crude oil foams are present in most steps of the oil industry, being one of the most complex and problematic non aqueous foams. During the crude oil exploitation, the presence of stable foams may cause major problems on surface equipment because of the depressurisation between the reservoir and the wellhead and the nucleation of the bubbles from the natural gas solubilised in the reservoir oil. These foams can fill up rapidly the half of the volume of the separators and cause serious damages due to the loss of the level control capacity, by dragging gas to the liquid line or liquid to the gas line, which leads to a reduction of the efficiency of the operation. The control of these foams is therefore a real issue. Several methods are used to control the foam based on its physical destruction (by mechanical devices, heating, special design of the unit internals...) but, by far, the most common method is the chemical destruction by adding different chemical compounds (called defoamers and antifoamers), particularly PDMS silicones. However, there is still no possible optimization of these treatments because of the lack of detailed studies on the behaviour of these complex systems. With this work we wanted to contribute to the understanding of the formation, stabilization and breaking mechanisms of this kind of non-aqueous foams. With this in mind, our first objective was the development of a new experimental methodology that allows to form crude oil foams which are representative of the oilfield foams, in order to compare the different foamy systems as well as the efficiency of different families of chemical additives. After that, we used a sigmoid model which describes in a satisfactory way the experimental curves of foam breaking. Besides, this kind of modelling allows to compare the efficiency of the different chemical additives in terms of defoaming and antifoaming effects, leading to the optimal selection of the additive in each case. Finally, these developments allow us to propose a first analysis of the influence of the physicochemical characteristics of these complex systems on their foaming properties.

<p>Electric arc furnace (EAF) is a furnace that utilizes electric energy and chemical energy to melt scraps and produce liquid steel. During the industrial process of EAF, an electric arc will be generated around the electrode located at the center of the furnace, and this phenomenon will generate a lot of heat. If any part of the electric arc is exposed to the freeboard region, a region above the slag layer inside the furnace, the heat emitted by this exposed arc can significantly heat on side wall temperatures, resulting in an overheating issue of side wall. Water-cooling panels (WCP) have been used to cool down the side wall, but the concentrated overheating area, may damage the water-cooling panel. In this study, a combination of slag foaming phenomenon and electric arc has been considered. A calculator is developed based on several arc models to calculate the parameters about slag foaming and arc power. The parameters can be used as input in a computational fluid dynamics (CFD) model. The commercial software, ANSYS FLUENT^®, was utilized to give a prediction of the side wall temperature distribution of an EAF. Data from the plant has been used to validate the calculation results. Furthermore, a series of parametric studies has been investigated to study the influence of operating conditions. The developed model can help to predict the risk of overheating from given electrode conditions and slag compositions.</p>

New methods for the preparation of porous biomedical scaffolds have been explored for applications in tissue engineering and drug delivery. Scaffolds with controlled pore morphologies have been generated which incorporate cyclodextrin-drug inclusion complexes as the drug delivery component. Supercritical CO2 was explored as the main processing fluid in the complex formation and in the foaming of the polymer scaffold. The co-solvents, ethanol, ethyl acetate and acetone, were explored in each stage, as needed, to improve the solvent power of CO2. The first goal was to promote cyclodextrin-drug complex formation. Complex formation by traditional methods was compared with complex formation driven by processing in supercritical CO2. Complex formation was promoted by melting the drug in supercritical CO2 or in CO2 + co-solvent mixtures while in the presence of cyclodextrin. Some drugs, such as piroxicam, are prone to degradation near the drug's ambient melting temperature. However, this approach using CO2 was found to circumvent drug thermal degradation, since drug melting temperatures were depressed in the presence of CO2. The second goal was to produce porous polymeric matrices to serve as tissue engineering scaffolds. Poly(lactide-<i>co</i>-glycolide) and poly(ε-caprolactone) were investigated for foaming, since these biomedical polymers are already commonly used and FDA approved. Polymer foaming with CO2 is an alternative approach to conventional solvent-intensive methods for porosity generation. However, two major limitations of polymer foaming using CO2 as the only processing fluid have been reported, including the formation of a non-porous outer skin upon depressurization and limited pore interconnectivity. Approaches to circumvent these limitations include the use of a co-solvent and controlling depressurization rates. The effect of processing parameters, including foaming temperatures and depressurization rate, as well as co-solvent addition, were examined in polymer foaming using CO2. Drug release dynamics were compared for foams incorporated with either pure drug, cyclodextrin-drug physical mixture or cyclodextrin-drug complex. Pore morphology, polymer choice and drug release compound choice were found to alter drug release profiles. / Ph. D.

Cílem práce byla příprava porézních vzorků HAP pro potenciálně medicínské aplikace. HAP byl připraven metodou sol-gel a precipitační. Vzorky HAP byly podrobeny analýze FTIR, XRD, SEM. Takto připravený HAP byl napěněn pomocí houbové metody s jasně definovanými póry a pomocí polymerního a skleněného expanzelu s různou distribucí a velikostí pórů. U výsledných napěněných vzorků byla vyhodnocena mikrostruktura a povrchová analýza pomocí SEM, zjištěna porozita pomocí Hg porozimetru a sledována bioaktivita in vitro v SBF. Byly zjištěny jasně definované makro, mezo a mikro póry při různé distribuci. U houbové metody pomocí sol-gel došlo k vytvoření jasně definovaných a pravidelných pórů s monodisperzní porozitou. Dominantní velikost póru byla stanovena v rozmezí 1–5 µm. Celková porozita byla stanovena na 63,5 % s celkovým povrchem 3,048 1 m/g. Precipitační metodou s polymerním expanzelem došlo k polydisperznímu rozložení pórů s třemi hlavními fázemi v rozmezí: 50–100 µm, 5–10 µm a 0,5–1 µm. Celková porozita byla stanovena na 67,6 % s celkovým povrchem 19,090 3 m/g. Bioaktivita výsledných napěněných vzorků in vitro byla sledována po dobu 7 dnů v připraveném SBF. Při napěnění sol-gel houbovou metodou nevznikla výsledná bioaktivní vrstva. U precipitační metody napěněné pomocí polymerního expanzelu vznikla nepravidelná bioaktivní vrstva. Výsledky byly naměřeny pomocí SEM analýzy.

The focus of my master’s thesis is a preparation of refractory insulating material made by foaming method. In the theoretic part are described properties of refractory materials especially thermal properties, classification of refractory materials and description of insulating refractory materials production. The experimental part of thesis focus firstly on problem solving during production process of material, characterization of materials with instrumentals method (SEM, XRD and TG-DTA-EGA) and examination of heat transfer in constructed equipment.

Doctoral thesis is focused on the study, research and development of heat insulating moulded refractory materials. The replacement of shaped instead of unshaped refractories is recently and strongly industrially demanded and belongs to ongoing research topics. With the increasing demand of energy savings, the excellent insulation properties are essential. The insulating properties of castables are the result of targeted porosity formation. The porosity is coming from the controlled air intrusion into material resulted to foamed structure. The foaming process was achieved by mixing of separately prepared aqueous foam into raw castable slurry or by in situ foaming of intensively mixed castable slurry with the surfactant additive. Nevertheless, the study of foam behaviour and the influence of additives on binder hydration and setting processes (i.e. calciumaluminate cement) was substantial for successful preparation of the experimental samples. The two types of the experimental samples were prepared. The first one was based on mixing of kaolin slurry with pre-prepared aqueous foam, whereas the de-aglomeration ability of kaolin specie was utilized to water-particle film formation. In situ foaming of multicomponent system is the second one. The both processes brought some negative attributes, so the optimal properties of prepared castables were achieved by their combination.

Résumé confidentiel / Résumé confidentiel

Plant-derived protein such as pea protein is a promising replacement for animal protein and is becoming popular in recent years because of its high nutritional value and potential reduction of environmental footprint. However, the increasing demand for plant-derived proteins is accompanied by the increase of wastes during protein processing such as wastewater containing dilute protein content, which may raise the cost for the downstream processing. Therefore, there is an emerging need to develop novel processing strategies to reduce waste while valorizing useful ingredients. Several researchers suggest that foam fractionation technology can be a viable approach to extract and concentrate protein from dilute wastewater effluent. This technology has already been applied to the chemical and food industry for the extraction of surfactant and animal proteins from wastewater. To design and apply foam fractionation to the plant-derived protein industry, fundamental knowledge on foaming properties of dilute plant-derived protein solution is needed and is currently lacking. Therefore, the objective of this thesis is to advance a fundamental understanding of the foaming properties of dilute pea protein solutions (protein concentration ≤ 1wt%). To achieve the objective, a multiscale approach is used, which is comprised of a detailed investigation of both bulk and interfacial properties of pea protein solutions and foaming properties such as foaming capacity and stability with the help of bubble structure and foam volume kinetics. The focus of this thesis is on the effect of protein concentration. Results demonstrate that protein adsorption kinetics can be characterized by four distinctive regimes: lag phase, diffusion-limited regime, transitional regime, and conformation change regime, which are highly dependent on the protein concentration. However, apparent viscosity is less affected by the protein concentration. Results also show that depending on the protein concentration, two regimes can be distinguished for foam capacity and foam stability. For the first time, these regimes can be rationalized by contrasting characteristics times of protein adsorption kinetics and processing time scale – residence time of bubbles during the foam formation. New findings from this fundamental research will shed light on the control and optimization of foaming properties of plant-derived protein solutions for applications ranging from food processing design to food product development.