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Today, in the automotive industry, many of the interior parts in the car are made of ABS and PC/ABS polymeric blend. These materials are used in the areas for example: instrument panels, tunnel consoles and door panels. The extensive use of these materials means that it is important to gain in-depth knowledge about the materials,their properties; and also their behaviour when in contact with different chemicals andat different conditions.This study aims to address the potential problem of the polymers used in the interiorof the car - ABS and PC/ABS cracking due to environmental factors. This study proposes to introduce a low-cost test method to compare the polymeric materials and choose the best one for future purposes with the environmental circumstances in mind for materials to have a good service life.During the thesis project, ABS and PC/ABS samples were tested for environmental stress cracking to compare the strained materials against PEG 400 and an assemblyfluid chemical. These tests were conducted at three different temperature levels.Differential Scanning Calorimetry (DSC) was used to verify the polymeric materialsthat the samples were made of. Optical microscope and FTIR were employed to analyzethe samples for crazes / cracks and degradation of material, respectively.This thesis helped in establishing a good starting point for ESC testing of different materials for the organization. The test method was used to test the failure of material sin ESC. It was observed that the chemicals used for the testing were aggressive and accelerated the cracking process in the materials rapidly. Another observation of the tests was that high strain also caused the materials to fail quickly. While comparing the materials, PC/ABS polymer blend was more resistant than ABS materials to cracking when exposed to same strain level during the creep rupture test (test in absence ofchemicals acting as a reference test for ESC).

Surface Plasmon Polaritons (SPPs) are considered to be attractive components for plasmonics and nanophotonic devices due to their sensitivity to interface changes, and their ability to guide and confine light beyond the diffraction limit. They have been utilized in SPP resonance sensors and near field imaging techniques and, more recently, SPP experiments to monitor and control ultrafast charge carrier and energy relaxation dynamics in thin films. In this thesis, we discuss excitation and propagation properties of ultrafast SPPs on thin extended metal films and SPP waveguide structures. In addition, localized and propagating surface plasmon interactions in functional plasmonic nanostructures will also be addressed. For the excitation studies of ultrafast SPPs, we have done detailed analysis of femtosecond surface plasmon pulse generation under resonant excitation condition using prism coupling technique. Our results show that photon-SPP coupling is a resonant process with a finite spectral bandwidth that causes spectral phase shift and narrowing of the SPP pulse spectrum. Both effects result in temporal pulse broadening and, therefore, set a lower limit on the duration of ultrafast SPP pulses. These findings are necessary for the successful integration of plasmonic components into high-speed SPP circuits and time-resolved SPP sensors. To demonstrate interactions between localized and propagating surface plasmons, we used block-copolymer based self assembly techniques to deposit long range ordered gold nanoparticle arrays onto silver thin films to fabricate composite nanoparticle thin film structures. We demonstrate that these gold nanoparticle arrays interact with SPPs that propagate at the film/nanoparticle interface and therefore, modify the dispersion relation of SPPs and lead to strong field localizations. These results are important and advantageous for plasmonic device applications. For the propagation studies of ultrafast SPPs, we have designed and constructed a home-built femtosecond photon scanning tunneling microscope (fsPSTM) to visualize ultrafast SPPs in photonic devices based on metal nanostructures. Temporal and phase information have been obtained by incorporating the fsPSTM into one arm of a Mach-Zehnder interferometer, allowing heterodyne detection. Understanding plasmon propagation in metal nanostructures is a requirement for implementing such structures into opto-electronic and telecommunication technologies.

No description available.

A ausência de adaptação passiva em prótese sobre implantes pode sobrecarregar implantes, componentes protéticos e tecido ósseo, levando à perda óssea marginal e até da osseointegração. A soldagem é utilizada com frequência para melhorar o assentamento de estruturas metálicas de próteses em geral e de próteses sobre implantes. Além disso, a precisão no assentamento da peça protética pode estar relacionada com os cuidados na técnica de confecção da mesma. Assim, o objetivo deste trabalho foi avaliar, por meio de microscopia óptica e confocal a laser, a adaptação marginal de barras metálicas tipo protocolo de Branemark, de ligas de niquel-cromo (NiCr) em monobloco e soldadas, confeccionadas a partir de enceramento convencional. Para isso, foi confeccionado um modelo mestre, simulando quatro implantes sobre o qual foram adaptados transferentes e análogos que serviram para transferir a posição dos implantes para o modelo de gesso. Os enceramentos obtidos pelo método convencional foram fundidos em monobloco e em partes separadas (seccionados), sendo os últimos, posteriormente soldados utilizando as técnicas convencional a maçarico e TIG (Tungsten Inert Gas). As leituras da adaptação da barra em cada implante foram feitas nas peças em monobloco (n=5) e nas peças seccionadas (n=10), antes e após as diferentes técnicas de soldagem. Pelo método de medição de microscopia óptica, foram realizadas as medições em duas regiões pré-determinadas ( Vestibular e Lingual ), com três repetições, totalizando 6 leituras por implante. Já no método de microscopia Confocal a laser, foi realizada somente na Vestibular. Para comparar os dados obtidos quanto ao desajuste marginal entre componente protético/implante, considerando-se as peças em monobloco, as peças soldadas, as técnicas de soldagem (maçarico e TIG), os métodos de medição e a posição dos implantes, foram realizados testes estatísticos, onde para cada uma das análises realizadas foi determinada a aplicação do Teste de Normalidade (Shapiro-Wilk ou Kolmogorov-Smirnov (alfa = 5%)) para determinação da distribuição da amostra. Para a amostra com distribuição normal foi determinada a utilização do teste paramétrico, Análise de Variância, enquanto que a amostra com distribuição não normal, determinou-se a utilização do teste não paramétrico de Kruskal Wallis. Os resultados encontrados foram estatisticamente significantes para comparação método e técnica, sugerindo que as peças em monobloco apresentaram maior desadaptação que as peças soldadas, e que as peças soldadas pela técnica convencional não apresentaram diferença estatística, em relação as soldadas pela técnica TIG. Em relação a comparação dos métodos de medição, houve diferença estaticamente significante, onde a microscopia Confocal a laser obteve os maiores valores de desadaptação. A interação técnica e método não houve diferenças estatísticas. Na comparação de diferentes secções e soldada, para os 2 métodos de medição, em relação ao fator Secção, não houve diferença significante onde 3 secções apresentam os menores resultados e as soldadas tiveram igualdade em relação a 1 secção. Pelo fator Técnica houve diferença estatisticamente significante, onde a técnica convencional obteve as maiores médias. A interação Secção e Técnica, não teve efeito significante. A adaptação marginal da peça em relação a posição do implante na arcada, não houve diferença estatística, para ambos os métodos. Houve diferença apenas no fator Técnica, pela microscopia óptica, onde a Monobloco teve os maiores resultados e a Solda Convencional e TIG, tiveram igualdade nos resultados. A investigação de sistemas de confecção de estruturas da prótese e de técnicas de soldagem é importante na busca pela produção de próteses sobre dente ou sobre implante com precisão no ajuste marginal que possa ser comprovado visual e numericamente utilizando-se recursos tecnológicos que assegurem a utilização clínica das peças protéticas. / The lack of passive adaptation in prosthesis over implant can overload implants, prosthetics components and bone tissue, leading to marginal bone loss and even osseointegration. Weldering is used frequently to improve the settlement of metal structures of prosthetic in general and prosthesis over implants. In addition, the settlement precision of the workpiece may be related to the care in the technique of manufacturing the same. The objective of this study was to evaluate, through optical and confocal Laser microscopy, the marginal adaptation of metal bars Branemark protocol type alloy nickel-chromium (NiCr) monoblock and welded, made from conventional waxing .For this, a master model was made to simulate four implants were adapted over which transferents and analogs that served to transfer the position of the implants for the cast model. Waxing obtained by the conventional method were cast in one-piece and separate parts (sectioned), the latter being subsequently welded using the conventional techniques blowtorch and TIG (Tungsten Inert Gas).The bar adjustment of readings in each implant were made in monoblock pieces (n = 5) and the severed pieces (n = 10) before and after different weldering techniques. By optical microscopy measurement method, measurements were performed in two predetermined regions (Vestibular and lingual), with three replications, totaling 6 readings per implant. However in the methodology of Confocal laser microscope, was done only on Vestibular. To compare the data obtained on the misfit between prosthetic/implant component, considering the pieces monoblock, the welded parts, the weldering techniques (torch and TIG), measurement methods and the position of the implants, tests were performed statistical where for each of the analyzes determined the application of Normality Test (Shapiro-Wilk test and Kolmogorov-Smirnov test (alpha = 5%)) to determine the distribution of the sample. For the sample of normal distribution was determined using the parametric test, analysis of variance, while the sample with non-normal distribution was determined using the nonparametric Kruskal-Wallis test. The results found were statistically significant for method and technique comparison, suggesting that the monoblock parts showed higher misfit than welded parts, and the parts welded by conventional technique showed no statistical difference in relation welded by TIG technique. Regarding the comparison of measurement methods, there was no statistically significant difference, where the Laser Confocal microscopy obtained the greatest misfit. The technical interaction and method there were no statistical differences. When comparing different sections and welded to the two measurement methods, in relation to Section factor, there was no significant difference where 3 sections have the lowest results and welded had equality with 1 section. The technical factor was no statistically significant difference, the conventional technique had the highest averages. The interaction and Technical Section had no significant effect. The marginal adaptation of the play in relation to the implant in the arch position, there was no statistical difference for both methods. There was a difference only in the technical factor, by optical microscopy, where Monoblock had the greatest results and Conventional Welding and TIG, had equality in results. The research of making the prosthesis structures systems and weldering techniques is important in the search for production of prosthetic tooth or on precisely implant the marginal adjustment that can be verified visually and numerically using technological resources to ensure clinical use of prosthetic pieces.

A ausência de adaptação passiva em prótese sobre implantes pode sobrecarregar implantes, componentes protéticos e tecido ósseo, levando à perda óssea marginal e até da osseointegração. A soldagem é utilizada com frequência para melhorar o assentamento de estruturas metálicas de próteses em geral e de próteses sobre implantes. Além disso, a precisão no assentamento da peça protética pode estar relacionada com os cuidados na técnica de confecção da mesma. Assim, o objetivo deste trabalho foi avaliar, por meio de microscopia óptica e confocal a laser, a adaptação marginal de barras metálicas tipo protocolo de Branemark, de ligas de niquel-cromo (NiCr) em monobloco e soldadas, confeccionadas a partir de enceramento convencional. Para isso, foi confeccionado um modelo mestre, simulando quatro implantes sobre o qual foram adaptados transferentes e análogos que serviram para transferir a posição dos implantes para o modelo de gesso. Os enceramentos obtidos pelo método convencional foram fundidos em monobloco e em partes separadas (seccionados), sendo os últimos, posteriormente soldados utilizando as técnicas convencional a maçarico e TIG (Tungsten Inert Gas). As leituras da adaptação da barra em cada implante foram feitas nas peças em monobloco (n=5) e nas peças seccionadas (n=10), antes e após as diferentes técnicas de soldagem. Pelo método de medição de microscopia óptica, foram realizadas as medições em duas regiões pré-determinadas ( Vestibular e Lingual ), com três repetições, totalizando 6 leituras por implante. Já no método de microscopia Confocal a laser, foi realizada somente na Vestibular. Para comparar os dados obtidos quanto ao desajuste marginal entre componente protético/implante, considerando-se as peças em monobloco, as peças soldadas, as técnicas de soldagem (maçarico e TIG), os métodos de medição e a posição dos implantes, foram realizados testes estatísticos, onde para cada uma das análises realizadas foi determinada a aplicação do Teste de Normalidade (Shapiro-Wilk ou Kolmogorov-Smirnov (alfa = 5%)) para determinação da distribuição da amostra. Para a amostra com distribuição normal foi determinada a utilização do teste paramétrico, Análise de Variância, enquanto que a amostra com distribuição não normal, determinou-se a utilização do teste não paramétrico de Kruskal Wallis. Os resultados encontrados foram estatisticamente significantes para comparação método e técnica, sugerindo que as peças em monobloco apresentaram maior desadaptação que as peças soldadas, e que as peças soldadas pela técnica convencional não apresentaram diferença estatística, em relação as soldadas pela técnica TIG. Em relação a comparação dos métodos de medição, houve diferença estaticamente significante, onde a microscopia Confocal a laser obteve os maiores valores de desadaptação. A interação técnica e método não houve diferenças estatísticas. Na comparação de diferentes secções e soldada, para os 2 métodos de medição, em relação ao fator Secção, não houve diferença significante onde 3 secções apresentam os menores resultados e as soldadas tiveram igualdade em relação a 1 secção. Pelo fator Técnica houve diferença estatisticamente significante, onde a técnica convencional obteve as maiores médias. A interação Secção e Técnica, não teve efeito significante. A adaptação marginal da peça em relação a posição do implante na arcada, não houve diferença estatística, para ambos os métodos. Houve diferença apenas no fator Técnica, pela microscopia óptica, onde a Monobloco teve os maiores resultados e a Solda Convencional e TIG, tiveram igualdade nos resultados. A investigação de sistemas de confecção de estruturas da prótese e de técnicas de soldagem é importante na busca pela produção de próteses sobre dente ou sobre implante com precisão no ajuste marginal que possa ser comprovado visual e numericamente utilizando-se recursos tecnológicos que assegurem a utilização clínica das peças protéticas. / The lack of passive adaptation in prosthesis over implant can overload implants, prosthetics components and bone tissue, leading to marginal bone loss and even osseointegration. Weldering is used frequently to improve the settlement of metal structures of prosthetic in general and prosthesis over implants. In addition, the settlement precision of the workpiece may be related to the care in the technique of manufacturing the same. The objective of this study was to evaluate, through optical and confocal Laser microscopy, the marginal adaptation of metal bars Branemark protocol type alloy nickel-chromium (NiCr) monoblock and welded, made from conventional waxing .For this, a master model was made to simulate four implants were adapted over which transferents and analogs that served to transfer the position of the implants for the cast model. Waxing obtained by the conventional method were cast in one-piece and separate parts (sectioned), the latter being subsequently welded using the conventional techniques blowtorch and TIG (Tungsten Inert Gas).The bar adjustment of readings in each implant were made in monoblock pieces (n = 5) and the severed pieces (n = 10) before and after different weldering techniques. By optical microscopy measurement method, measurements were performed in two predetermined regions (Vestibular and lingual), with three replications, totaling 6 readings per implant. However in the methodology of Confocal laser microscope, was done only on Vestibular. To compare the data obtained on the misfit between prosthetic/implant component, considering the pieces monoblock, the welded parts, the weldering techniques (torch and TIG), measurement methods and the position of the implants, tests were performed statistical where for each of the analyzes determined the application of Normality Test (Shapiro-Wilk test and Kolmogorov-Smirnov test (alpha = 5%)) to determine the distribution of the sample. For the sample of normal distribution was determined using the parametric test, analysis of variance, while the sample with non-normal distribution was determined using the nonparametric Kruskal-Wallis test. The results found were statistically significant for method and technique comparison, suggesting that the monoblock parts showed higher misfit than welded parts, and the parts welded by conventional technique showed no statistical difference in relation welded by TIG technique. Regarding the comparison of measurement methods, there was no statistically significant difference, where the Laser Confocal microscopy obtained the greatest misfit. The technical interaction and method there were no statistical differences. When comparing different sections and welded to the two measurement methods, in relation to Section factor, there was no significant difference where 3 sections have the lowest results and welded had equality with 1 section. The technical factor was no statistically significant difference, the conventional technique had the highest averages. The interaction and Technical Section had no significant effect. The marginal adaptation of the play in relation to the implant in the arch position, there was no statistical difference for both methods. There was a difference only in the technical factor, by optical microscopy, where Monoblock had the greatest results and Conventional Welding and TIG, had equality in results. The research of making the prosthesis structures systems and weldering techniques is important in the search for production of prosthetic tooth or on precisely implant the marginal adjustment that can be verified visually and numerically using technological resources to ensure clinical use of prosthetic pieces.

The goal of this thesis is to describe the possibility of using a microscope for documentation defects and innovation of electrical machines. I used an electron microscope to document carbon brushes and nanomaterials for possible upgrade of the sliding contact. Use microscopes gives us detailed information about the structure of materials, at the largest stress of the electrical machine. Based on the collected data can be further analyzed and innovation of the carbon brush.

A programmable illuminating system (PIS) uses a commercial multimedia projector together with a suitable optical relay system in order to illuminate specimens under microscope with transmitted light. The theoretical part of the diploma thesis describes some methods used in the optical transmission microscopy. All of these methods employ physical masks placed in the condenser front focal plane. In the case of the traditional methods the masks are used to enhance contrast (e.g. dark-field illumination) and resolution (oblique illumination). One of the methods (a condenser with rotating aperture) provides the information about the three-dimensionality of the specimen. The next part of the thesis contains the theory and the basic classification of the illuminating systems used in the optical transmission microscopy. An optical and mechanical design of the optical relay system used for PIS is introduced. The experimental part shows the results made with two different PIS arrangements. It was shown on two different specimens that the PIS provides the same illumination as the classical methods. It was also proved that the PIS can simulate the rotating aperture in the condenser front focal plane and thus to give the information about the three-dimensionality of the specimen. Some new static and dynamic illuminating methods were introduced.

This diploma thesis is focused on composition and processing of cellulose fibers and their usage in cementitious composites. It describes key attributes of cellulose fibers, which has to be acquired for effective use in cement composites. There are stated effects of cellulose fibers on concrete properties, such as workability, physical and mechanic attributes and freeze-thaw resistance. In experimental part is designed a mixture with portion of cellulose fibers. There has been performed various tests to define the effect of cellulose fibers. There was designed experiment to determine its alkali resistance for fibers itself, and possible changes in microstructure of fibers were analyzed by optic and electron scanning microscope.

This work were requested by Uddeholms AB. Uddeholm is the worldś leading manufacturer of high performance tool steel for industrial tools. The company exists worldwide and is present in over 100 countries. One of the company’s main production processes is manufacturing powder steels with extremely high quality. In this work, one of these steels has been analyzed to evaluate the presence and distribution of non-metallic inclusions. Higher demands on quality and more global competition worldwide means that you always have to strive towards perfection in the manufacturing processes. Non-metallic inclusions have severe effects on the mechanical properties of steels. That's why it's of utmost importance to investigate their presence in the tool steel and especially their size. The reason for this is because it's the largest inclusions that's the most dangerous for the material. To obtain a statistically number of certainty of the largest of inclusions, very vast areas of steel have to be examined. Therefore a theoretical method of extrapolation is often used instead to approximate the distribution of the largest inclusions. The precision of this method is still very uncertain. Different methods of this kind of analysis do exist. The method applied in this work of degree is extreme values analysis by statistics of extreme values (SEV). To ensure the pre-conditions of the extreme values analysis, a large quantity of powder steel was analyzed. This was done by light-optic microscopy (LOM) and exclusively performed by Uddeholms AB at their R&D-facility (Research and development-facility) in Hagfors. At Karlstad Universityś test-facility specimens were subjected to ultrasonic fatigue testing at 20 kHz. The specimens derived from the same material as the ones examined in LOM. The result from the ultrasonic fatigue testing were that the largest inclusions in the material were found. This was done by applying very high cycle fatigue (VHCF). To calculate the maximum theoretical inclusion size, SEV was used. The extreme values analysis was performed on gathered data from both LOM and VHCF. All fracture surfaces from the ultrasonic fatigue testing were then examined in scanning electron microscope (SEM) at Karlstad University. In SEM, the largest inclusion in every fractured surface was identified and measured. The maximum real inclusion size from the fractured surfaces was then compared to the maximum theoretically calculated inclusion size from the extreme values analysis. As it turned out the real inclusion size proved to be slightly larger than the theoretical. The difference between them was found to be 3,25 µm. Conclusions drawn were that Uddeholms powder steel exhibits very high purity and that extreme values analysis as an analytical method is recommended. However, the analysis should be repeated to underline the chosen solution methodology.