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The submitted Ph.D. thesis concerns anion receptors based on symmetrically tetrasubstituted cone calixf4]arenes. These receptors are easily synthesized and display sufficient water solubility to function as receptors for tetrahedral oxoanions. The thesis starts with a brief survey of literature on calix[4larene anion receptors and sensors. The theoretical part of the thesis deals with a stereochemical investigation of calixf4]arenes from the Cambridge Structural Database (CSD) with emphasis on the influence of inter- and/or intramolecular interactions on the geometry and rigidity of the calix[4]arene scaffold. In order to describe the geometry of the calixf4]arene moiety, it was necessary to introduce new stereochemical parameters cr, B and 5. The utility of these parameters in evaluating the geometry of the calixf4]arene base frame was confirmed. The stereochemical investigation formed the basis for design of new potential anion receptors based on symmetric al ly tetrasub stituted c o n e calixl4 ] arene s. The experimental part of this work started with synthesis of symmetrically tetrasubstituted calixf4]arene derivatives containing 1-propoxy groups at the lower rim and synthesis of calixf4]arene derivatives with carboxymethoxy groups at the lower rim and enhanced water solubility. Identity and...

Departamento Nacional de ProduÃÃo Mineral / Na RegiÃo Metropolitana de Fortaleza vÃrias indÃstrias cerÃmicas, cujo principal produto à a fabricaÃÃo de tijolos, tem enfrentado grandes problemas devido à necessidade de reaproveitamento da massa cerÃmica, ou mesmo a perda da mesma apÃs a queima, por nÃo atender as especificaÃÃes do mercado. Isso decorre na maioria das vezes devido à proporÃÃo de mistura da matÃria-prima introduzida no processo ser inadequada, decorrente da falta de conhecimento de suas caracterÃsticas, acarretando no consumo adicional de energia elÃtrica, subutilizaÃÃo dos equipamentos e mÃo-de-obra e, consequentemente, aumento dos custos de produÃÃo. A caracterizaÃÃo tecnolÃgica das argilas utilizadas em algumas cerÃmicas da regiÃo pode fornecer subsÃdios para melhoria do processo utilizado nessas indÃstrias. A metodologia utilizada nesse trabalho envolveu a seleÃÃo de Ãreas de extraÃÃo para caracterizaÃÃo tecnolÃgica da argila e definiÃÃo de uma proporÃÃo de mistura adequada para fabricaÃÃo de tijolos, com base na matÃria-prima utilizada por cada indÃstria cerÃmica selecionada, alÃm de avaliar a qualidade do material argiloso para fabricaÃÃo de telhas. Paralelamente foram realizadas anÃlises de difraÃÃo/fluorescÃncia de raios X e microscopia eletrÃnica de varredura, onde foi possÃvel verificar uma predominÃncia de argilas caulinÃticas e ilÃticas nas argilas aluvionares da regiÃo, sendo tambÃm observadas associaÃÃes intestratificadas de caulinita e esmectita. Tais anÃlises tambÃm foram aplicadas com o propÃsito de identificar propriedades que pudessem interferir no processo cerÃmico. Com base nos resultados de caracterizaÃÃo tecnolÃgica foi identificado que somente uma amostra pode ser utilizada diretamente na fabricaÃÃo de telhas ou tijolos, sem a necessidade de mistura. Com relaÃÃo Ãs demais amostras, as proporÃÃes definidas para misturas de argilas se mostraram satisfatÃrias para fabricaÃÃo de produtos voltados para cerÃmica vermelha. / In the metropolitan area of Fortaleza various ceramic industries, whose main product is the manufacture of bricks, has been facing major problems due to the need to reuse the ceramic body, or even the loss of it after firing, for not meeting the specifications of the market. This occurs mostly due to the mixing ratio of the raw material introduced into the process is inadequate, due to the lack of knowledge of its characteristics, resulting in additional electricity consumption, under-utilization of equipment and skilled labor and hence increase in production costs. The technological characterization of clays used in some ceramics of the region can provide input for improvement of the process used in these industries. The methodology used in this work involved the selection of extraction areas for technological characterization of the clay and setting a ratio of adequate mixing for the manufacture of bricks, based on the raw material used by each selected ceramic industry, and to evaluate the quality of material for the manufacture of clay tiles. Parallel analyzes were performed X-ray diffraction and fluorescence and scanning electron microscopy, where we observed a predominance of kaolinite and ilÃticas clays in alluvial clays of the region, being also observed interstratified kaolinite and smectite associations. Such analysis was also applied in order to identify properties that could interfere with the ceramic process. Based on the results of technological characterization was identified that only one sample may be used directly in the manufacture of tiles or bricks, without the need for mixing. Among the remaining samples, the proportions set to mixtures of clays seem to be satisfactory for the manufacture of products for red ceramics.

Electric and hybrid vehicles uses regenerative braking, where application of the brake triggers the electric motor to work as a generator to produce electricity, which in turn charges the battery. This results in much less use of the friction brake, changing the corrosion and wear behavior of the rotor surface. There is a need for research on this topic, since fully electric or hybrid vehicles are replacing combustion engines due to concerns about global warming and climate change. Here the corrosion behavior of coated cast iron vehicle rotors in 3.5wt% NaCl is studied. The corrosion study has been performed using electrochemical methods such as cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). All the coated samples were provided by Pure Forge Rotors. Based on the results from SEM and EDX, the coating is atomic forge proprietary coating, and the base material is gray cast iron. Our primary objective is to study the corrosion behavior of coated, non-coated and friction-tested samples. CV experiments indicate a shift in the corrosion potential and corrosion current density due to changes in the nature of the exposed surface. Cross-sectional SEM showed the thickness of the coating to be 16-23 µm. After friction testing, the friction layer created by rubbing the brake pad over the rotor plays a role in corrosion resistance, but this depends on the type of brake pad material (i.e. semi-metallic, non-asbestos organic and low metallic). Results showed that friction film that forms after testing against non-asbestos organic pads provides the highest corrosion resistance amongst the three brake pad materials.

Due to the risk of complications such as hemorrhage, severe pelvic trauma is associated with a high mortality rate. Prompt medical treatment is therefore vital. However, the complexity of the injuries can make successful diagnosis and treatment challenging. By generating predictions and recommendations based on patient data, computer-aided decision support systems have the potential to assist physicians in improving outcomes. However, no current system considers features automatically extracted from medical images. This dissertation describes a system to extract diagnostic features from pelvic X-ray images that can be used as input to the prediction process; specifically, the presence of fracture and quantitative measures of displacement. Feature extraction requires prior identification of separate structures of interest within the pelvis. The proposed system therefore incorporates a hierarchical segmentation algorithm which is able to automatically extract multiple structures in a single pass, using a combination of anatomical knowledge and computational techniques such as directed Hough Transform. This algorithm also applies a novel Spline/ASM segmentation method which combines cubic spline interpolation with a deformable model approach which maintains curved contours and provides local control over segmentation. In order for the proposed system to be used as a component in a computerized decision support system, segmentation is designed to be entirely automatic. Furthermore, Spline/ASM is suitable for many other segmentation applications where the objects of interest show curved contours. After successful segmentation, fracture detection is performed on the pelvic ring and pubis structures, using an algorithm based on wavelet transform, anatomical information and boundary tracing. A method is also developed to calculate quantitative measures of symphysis pubis displacement that may indicate pelvic instability and prove useful in identifying fracture patterns. Finally, X-ray features are combined with patient demographics and physiological scores for generation of predictive rules for injury severity, with promising current results. This indicates the potential diagnostic value of the extracted features, and in turn the usefulness of the proposed radiograph analysis component in a larger decision support system.

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