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The main objective of the study was to determine the effects of enzymes on quality of breads baked in halogen lamp-microwave combination, microwave and conventional oven. It was also aimed to determine the optimum processing conditions in these ovens. In the first part of the study, as independent variables, baking time, baking temperature for conventional oven / microwave power for microwave oven and microwave power and halogen power for combination oven was used. Weight loss, specific volume, firmness and color of the breads were measured during the study. The optimum baking conditions were determined as 13 min at 200&deg / C in conventional oven, 0.75 min at 100% power in microwave oven, 10 min at 60% power in halogen lamp oven, and 3 min at 30% microwave power and 70% halogen lamp power in halogen lamp-microwave combination oven. In the case of combination oven, specific volume and color values of breads were comparable with the conventionally baked breads but weight loss and firmness of them were still higher. The effects of different enzymes (&amp / #945 / -amylase, xylanase, lipase &amp / protease) were studied to reduce the quality problems of breads baked in microwave and halogen lamp-microwave combination oven. The optimum baking conditions determined for each type of oven in the first part of the study were used in the investigation of the functions of enzymes on bread quality during baking and staling. As a control, no enzyme added breads baked at 200&deg / C for 13 min in conventional oven were used. All the enzymes were found to be effective in reducing initial firmness and increasing specific volume of breads baked in microwave and halogen lamp-microwave combination ovens. However, in conventional baking, the effects of enzymes on crumb firmness were seen mostly during storage. The usage of enzyme protease in the bread formulation resulted in breads with higher volume and darker color in all of the ovens. All of the enzymes were found to be effective to retard the staling of breads baked in conventional, microwave and halogen lamp-microwave combination ovens.

The main objective of this study was to optimize processing conditions during halogen lamp-microwave combination baking of cake by using Response Surface Methodology. It was also aimed to compare quality of products baked in microwave-halogen lamp combination oven, halogen lamp oven, microwave oven and conventional oven. In the first part of the study, as independent variables, baking time for conventional oven / microwave power and baking time for microwave oven / halogen lamp power and baking time for halogen lamp oven and microwave power, halogen lamp power and baking time for halogen lamp-microwave combination oven were used. Weight loss, specific volume, firmness and color of the cakes were measured during the study. Cakes baked in conventional oven at 175&deg / C for 24 minutes were determined as the control cakes. Weight loss of cakes increased with increasing independent variables for all oven types. Specific volume and firmness of cakes increased with increasing microwave power, but decreased with upper halogen lamp power. Color formation was achieved in the combination baking but not as much as in the conventional baking. Response Surface Methodology was used to optimize the baking conditions in the second part of the study. Upper and lower halogen lamp powers, microwave power and baking time were used as independent variables. Optimum processing conditions were found as 60% for upper halogen lamp power, 70% for lower halogen lamp power, 30% for microwave power and 5 minutes for baking time. Cakes baked at optimum baking conditions had comparable quality with conventionally baked ones, except color. In short, by the usage of halogen lamp-microwave combination oven it was possible to obtain high quality cakes by reducing of conventional baking time about 79%.

CoordenaÃÃo de AperfeiÃoamento de NÃvel Superior / O presente trabalho trata do estudo, construÃÃo e teste de um forno tubular rotativo, para a calcinaÃÃo e obtenÃÃo de Ãxidos metÃlicos a partir do processo sol-gel protÃico convencional. A abordagem da pesquisa visa aumentar a eficiÃncia energÃtica com o propÃsito de reduzir o dispÃndio de energia e de tempo na obtenÃÃo de nanopartÃculas, utilizando-se 6(seis) lÃmpadas halÃgenas de tungstÃnio de base bilateral com 1000W/220V cada uma. Este forno à capaz de realizar sÃntese com boa homogeneizaÃÃo pela rotaÃÃo do pà durante a calcinaÃÃo com o diferencial do uso de lÃmpadas halÃgenas, que possibilitam um elevado aquecimento e resfriamento da amostra. Os componentes foram capazes de resistir a elevadas temperaturas, dotados de difÃcil oxidaÃÃo, e os isolantes tÃrmicos eficientes por sua baixa condutividade tÃrmica a fim de obter baixas perdas de calor pelas paredes do forno. O processo de montagem foi marcado por vÃrias melhorias em relaÃÃo ao projeto original, visto que a princÃpio o forno nÃo contava com o sistema de refrigeraÃÃo e sua utilizaÃÃo melhorou a eficiÃncia e conservaÃÃo das lÃmpadas halÃgenas. Os resultados da pesquisa evidenciam a eficiÃncia do forno de lÃmpadas halÃgenas em relaÃÃo ao forno a resistÃncia quanto ao tamanho da partÃcula e sua homogeneizaÃÃo, bem como quanto a perda de calor. Neste Ãltimo item atingindo um rendimento melhor em torno de 50% comparado ao forno a resistÃncia elÃtrica. / This paper deals with the study, construction and testing of a rotary tube furnace for calcinations and obtaining metal oxides from the conventional sol-gel protein process. The research approach aims to increase energy efficiency in order to reduce the expenditure of energy and time to obtain nanoparticles, using 6 (six) bilateral basis tungsten halogen lamps with 1000W/220V each one. This furnace is able to perform synthesis with good mixing by rotation of the powder during calcination with the differential use of halogen lamps, which enables a high heating and cooling of the sample. The components were able to withstand high temperatures, equipped with hard oxidation, and the efficient thermal insulation by low thermal conductivity in order to obtain low heat loss through the walls of the oven. The assembly process was marked by several improvements over the original design, since the beginning, the oven did not have the cooling system and its use has improved efficiency and conservation of halogen lamps. The research results show the better efficiency of the furnace of halogen lamps in comparison to the resistance furnace on the particle size and its homogeneity, as well as the loss of heat. In this last item reaching a better yield around 50% compared to electric resistance furnace.

The main objective of this study was to optimize the processing conditions of breads baked in halogen lamp-microwave combination oven by using response surface methodology. It was also aimed to construct neural network models for the prediction of quality parameters of bread as a function of processing conditions. Different baking time and power combinations were used in order to find the optimum baking conditions of bread in halogen lamp-microwave combination oven. The independent variables were the baking time (4, 4.5, 5, 5.5, and 6 min), power of upper and lower halogen lamps (40, 50, 60, 70, and 80%), and power of the microwave (20, 30, 40, 50, and 60%). As control, breads baked in conventional oven at 200&ordm / C for 13 min were used. The measured quality parameters were the weight loss, color change, specific volume, porosity, and texture profile of the breads. Baking time, upper halogen lamp power, and microwave power were found to be significant on affecting most of the quality parameters. On the other hand, lower halogen lamp power was found to be an insignificant factor for all of the responses. For the optimization process, Response Surface Methodology (RSM) was used. The optimum baking conditions were determined as 5 min of baking time at 70% upper halogen lamp power, 50% lower halogen lamp power, and 20% microwave power. Breads baked at the optimum condition had comparable quality with conventionally baked ones. When halogen lamp-microwave combination oven was used, conventional baking time of breads was reduced by 60%. Artificial neural network models were developed for each of the quality parameters in order to observe the effects of the baking time and different oven conditions on the quality of the breads. High regression coefficients were calculated between the experimental data and predicted values showing that this method is capable in predicting quality parameters of breads during halogen lamp-microwave combination baking. In addition, the results were comparable to the RSM study.

Objetivo: Este estudo se propõe a verificar a influencia do tipo de luz fotopolimerizadora na força de retenção de pinos intra-radiculares, tanto na técnica direta como na direta indireta. Métodos: 40 raízes de dentes bovinos com comprimento de 12 mm foram tratadas endodonticamente e divididas aleatoriamente em 4 grupos de acordo com a técnica de obtenção dos pinos e luz fotopolimerizadora (n=10): grupo 1 (técnica direta associada à lâmpada halogena); grupo 2 (técnica direta ao LED); grupo 3 (técnica direta-indireta associada à lampada halógena); e grupo 4 (técnica direta-indireta associada ao LED). A força de retenção foi determinada através do teste de tração usando Universal Testing Machine (Instron). Todos os dados foram analisados usando one-way analysis of variance (ANOVA) com a significância de p<0.05 e complementadas com teste de Tukey. Após o teste, as interfaces adesivas onde ocorreram as falhas foram examinadas e classificadas. Resultado: Os grupos 3 (246,05N ± 29,51) e 4 (241,60N ± 28,95) não apresentaram força de retenção estatisticamente diferente mas foram maiores que os grupos 1 (142,30N ± 25,60) e 2 (178,56N ± 25,67). A maior parte das fraturas ocorreu na interface dentina/resina. Conclusão: Com base nos resultados obtidos, concluímos que o método direto-indireto proporcionou a melhor retenção dos pinos de fibra de vidro. / Objectives: The purpose of this study is to verify the influence of light curing type on retention force of direct technique and direct-indirect technique. Methods: Fourth bovine single root teeth with 12mm of length were used in this study. The roots were endodontically treated and randomly divided in four groups according to the light curing unit and technique used: group 1(direct technique, halogen lamp), group 2(direct technique, LED), group 3(direct-indirect technique, halogen lamp), group 4(direct-indirect technique, lamp). The retention force was determined sing a Universal Testing Machine (Instron). All data were analyzed using one-way analysis of variance (ANOVA) and Tukey test. After the test, the failure was examined and classified according to the fracture place: post/ resin; resin/dentin; mix. Results: Group 3 (246,05N ± 29,51) and 4(241,60N ± 28,95)4 (95,18N) did not show statistically difference but presented higher retention force than group 1 (142,30N ± 25,60) and 2 (178,56N ± 25,67). Most of fracture occurred in interface between dentin/resin. Conclusion: Based on the obtained results, it was concluded that adhesive cementation technique influenced in the retention of glass fiber post.

Objetivo: Este estudo se propõe a verificar a influencia do tipo de luz fotopolimerizadora na força de retenção de pinos intra-radiculares, tanto na técnica direta como na direta indireta. Métodos: 40 raízes de dentes bovinos com comprimento de 12 mm foram tratadas endodonticamente e divididas aleatoriamente em 4 grupos de acordo com a técnica de obtenção dos pinos e luz fotopolimerizadora (n=10): grupo 1 (técnica direta associada à lâmpada halogena); grupo 2 (técnica direta ao LED); grupo 3 (técnica direta-indireta associada à lampada halógena); e grupo 4 (técnica direta-indireta associada ao LED). A força de retenção foi determinada através do teste de tração usando Universal Testing Machine (Instron). Todos os dados foram analisados usando one-way analysis of variance (ANOVA) com a significância de p<0.05 e complementadas com teste de Tukey. Após o teste, as interfaces adesivas onde ocorreram as falhas foram examinadas e classificadas. Resultado: Os grupos 3 (246,05N ± 29,51) e 4 (241,60N ± 28,95) não apresentaram força de retenção estatisticamente diferente mas foram maiores que os grupos 1 (142,30N ± 25,60) e 2 (178,56N ± 25,67). A maior parte das fraturas ocorreu na interface dentina/resina. Conclusão: Com base nos resultados obtidos, concluímos que o método direto-indireto proporcionou a melhor retenção dos pinos de fibra de vidro. / Objectives: The purpose of this study is to verify the influence of light curing type on retention force of direct technique and direct-indirect technique. Methods: Fourth bovine single root teeth with 12mm of length were used in this study. The roots were endodontically treated and randomly divided in four groups according to the light curing unit and technique used: group 1(direct technique, halogen lamp), group 2(direct technique, LED), group 3(direct-indirect technique, halogen lamp), group 4(direct-indirect technique, lamp). The retention force was determined sing a Universal Testing Machine (Instron). All data were analyzed using one-way analysis of variance (ANOVA) and Tukey test. After the test, the failure was examined and classified according to the fracture place: post/ resin; resin/dentin; mix. Results: Group 3 (246,05N ± 29,51) and 4(241,60N ± 28,95)4 (95,18N) did not show statistically difference but presented higher retention force than group 1 (142,30N ± 25,60) and 2 (178,56N ± 25,67). Most of fracture occurred in interface between dentin/resin. Conclusion: Based on the obtained results, it was concluded that adhesive cementation technique influenced in the retention of glass fiber post.

The aim of master´s thesis is to get acquainted with the design and materials used in selected automotive light source – tungsten halogen lamp. Further, the thesis focused on the theory and appropriate selection of the thermal measurement method on a real sample. Subsequently, a model of the light source and its simulation in the ANSYS – Maxwell 3D and Mechanical programs are created. Finally, the results of the thermal simulation and the non-contact measurement of the tungsten halogen lamp are evaluated