The main object of this diploma thesis is solving problems concerning heat transfer in disposal cannister for spent nuclear fuel. In forepart possibilities of conceptual solving according of disposal cannister to particular states are reviwed. On the basis of this a variant of possible protect of a nuclear fuel repository in the Czech republic has been chosen for calculationof a simplified model. Second part is computational solving that was divided into two parts. The first deals with calculation of heat transfer in disposal canister and is done by an analytical method. In the second part is calculation is done by numerical model. In this way region in near surroundings of this model of disposal cannister is analysed. Last part those diploma thesis deals with design of the storage of spacing among disposal canisters as well as optimum placing in underground part of nuclear fuel repository.

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The “green agenda” combined with highway congestion has accelerated the demand for increased freight and passenger travel on the world’s railways. These increases have driven demand for more efficient and rapid investigation of trackbed ballast. Network Rail and other rail infrastructure operators spend significant financial sums on inspecting, tamping, adjusting, cleaning, and replacing trackbed ballast. Such maintenance is often to the detriment of normal network operation. Industry requires a method of ballast evaluation that is non-intrusive, cheap, can appraise long stretches of track in a short period of time, and give a fingerprinting result from which time-to-maintenance can be calculated and planned. Thus, the aim was to develop evaluation methods using non-destructive testing techniques. A 10-year old full-scale trackbed composed of variously fouled ballast was re-visited and used for experimentation. The condition of the ballast was calculated using the Ionescu Fouling Index. Earlier research at the University of Edinburgh enabled researchers worldwide to characterise ballast using ground penetrating radar (GPR). This research was repeated, validated and taken forward in a series of GPR experiments on the trackbed using a range of antennas from 500MHz to 2.6GHz. New "scatter" metrics were developed to determine ballast condition from the GPR waveforms. These metrics were then used to predict the Ionescu Fouling Index with a correlation coefficient greater than 0.9. One of the current approaches to evaluating the stiffness of railway ballast is to use a Falling Weight Deflectometer (FWD). The viability of using a Prima 100 mini-FWD on railways to measure stiffness was determined and deemed to be ineffective on ballast. The applicability of the impulse response technique on railways was determined. An instrumented hammer was used to excite the ballast, with a geophone measuring the response. The Frequency Response Function of this was successfully correlated with the Ionescu Fouling Index with a correlation coefficient also greater than 0.9. Finally, using GPR data and measured stiffness data collected by Banverket, Sweden, a numerical model to successfully relate radar responses to stiffness was developed.

The United States' fleet of Light Water Reactors (LWRs) produces a large amount of spent fuel each year; all of which is presently intended to be stored in a fuel repository for disposal. As these LWRs continue to operate and more are built to match the increasing demand for electricity, the required capacity for these repositories grows. Georgia Tech's Subcritical Advanced Burner Reactor (SABR) has been designed to reduce the capacity requirements for these repositories and thereby help close the back end of the nuclear fuel cycle by burning the long-lived transuranics in spent nuclear fuel. SABR's design is based heavily off of the Integral Fast Reactor (IFR). It is important to understand whether the SABR design retains the passive safety characteristics of the IFR. A full safety analysis of SABR's transient response to various possible accident scenarios needs to be performed to determine this. However, before this safety analysis can be performed, it is imperative to model all components of the reactivity feedback mechanism in SABR. The purpose of this work is to develop a calculational model for the fuel bowing reactivity coefficients that can be used in SABR's future safety analysis. This thesis discusses background on fuel bowing and other reactivity coefficients, the history of the IFR, the design of SABR, describes the method that was developed for calculating fuel bowing reactivity coefficients and its validation, and presents an example of a fuel bowing reactivity calculation for SABR.

In this thesis, the response of uranium minerals and poorly crystalline phases to changes in geochemical conditions through geological time has been assessed in order to understand the mobility of natural uranium in the fracture network of a proposed site for a spent nuclear fuel repository in Forsmark, Sweden. Identification and characterization of solid phase uranium have been performed through electron microprobe analysis and optical petrography (Article I). The identified uraninite, haiweeite, and uranophane crystals have been dated using U-Pb and Pb-Pb isotope ratios obtained from secondary ion mass spectrometry and laser ablation-inductively coupled plasma-mass spectrometry (Article II). The mobility of uranium in current Forsmark groundwaters and fracture system has been modelled using the PHREEQC geochemical program and Ra and Rn isotope systematics (Article IV). The rate of submarine groundwater discharge (SGD) from the Forsmark coast to Öregrundsgrepen has also been modelled using Ra isotopes (Article V). Results from these studies support a geologically early (~1200 Ma) oxidation of U(IV) to U(VI). It is further suggested that the old U(VI) minerals present in the bedrock are soluble at the pe values and alkalinities observed in the Forsmark groundwaters. At pe &lt; −4.6 and alkalinity &lt; 60 mg/L, U(VI) can be reduced to U(IV) and deposited in the fracture network. Although a non-negligible rate of SGD has been observed, this cannot be attributed to the discharge of deep (&gt;200 m.b.s.l.) Forsmark groundwaters on the basis of current data. / <p>At the time of the doctoral defense, the following papers were unpublished and had a status as follows: Paper 2: Manuscript. Paper 3: In press. Paper 4: Manuscript. Paper 5: Manuscript.</p>

Master of Science / Department of Family Studies and Human Services / Jared R. Anderson / The present study tests the reciprocal relationships between marital attitudes, time spent together, and marital satisfaction in a sample of newlyweds (N = 1220). Using cognitive dissonance theory and the investment model, this study tests two sets of theoretically derived unidirectional pathways to provide empirical evidence for longitudinal associations between these three constructs. Two separate models were tested, one for husbands, and one for wives. For both husbands and wives, results of the panel models indicated significant autoregressive paths among all three variables from T1 to T2, T2 to T3, and T1 to T3. Among husbands, significant cross-lagged paths emerged between T1 marital satisfaction and T2 marital attitudes, T1 marital satisfaction and T2 time spent together, T1 time spent together and T2 marital satisfaction, T2 time spent together and T3 marital satisfaction, and T2 time spent together and T3 marital attitudes. For wives, cross-lagged paths between T1 marital satisfaction and T2 time spent together, T1 time spent together and T2 marital satisfaction, and T2 time spent together and T3 marital satisfaction were found to be significant. Bootstrap test for indirect effects resulted in no significant mediating effects in the models. The results of these models are discussed and implications for future research and intervention are given.

O presente estudo teve como objetivo avaliar a produção de etanol pela levedura Pichia stipitis, a partir do hidrolisado hemicelulósico do bagaço de malte (HHBM). Primeiramente estudou-se o efeito da suplementação nutricional do hidrolisado adicionando-se extrato de farelo de arroz (0 a 20% v/v), uréia (0 a 3 g/L) e extrato de levedura (0 a 3 g/L). Os resultados mostraram que o hidrolisado suplementado apenas com extrato de levedura proporcionou os melhores resultados de conversão (YP/S = 0,44 g/g) e produtividade em etanol (QP = 0,33 g/L.h). Em seguida foi avaliado o nível ótimo deste nutriente sobre a bioconversão, sendo confirmada a suplementação do HHBM com 3,0 g/L de extrato de levedura. Após o estabelecimento das condições nutricionais, a levedura foi cultivada em HHBM após o crescimento de 24 horas em meio semissintético, visando aclimatar as células aos inibidores presentes no hidrolisado. Este estudo resultou no aumento das velocidades do processo, sendo 16% sobre a produtividade volumétrica em etanol (QP) e 10% sobre a velocidade de consumo de substrato (QS), quando comparado ao cultivo das células somente em meio semissintético. Na etapa seguinte utilizou-se um planejamento fatorial 22 com face centrada para otimização das condições de pH e concentração inicial de células (X0) na fermentação em HHBM não destoxificado e após a destoxificação com carvão ativado. Foram obtidos modelos para descrever os valores de YP/S e QP na região estudada, sendo que para o HHBM não destoxificado os valores destes parâmetros foram 0,40 g/g e 0,65 g/L.h, respectivamente, em pH 6,4 e X0 = 5,0 g/L (modelo 1). Em HHBM destoxificado, as condições ótimas foram obtidas em pH 6,0 e 1,36 g/L de células (modelo 2), obtendo-se YP/S de 0,40 g/g e QP de 0,46 g/L.h. Nas condições otimizadas foram então realizados ensaios que confirmaram a validade dos modelos 1 e 2, obtendo-se a máxima concentração de etanol (23,4 g/L), YP/S de 0,41 g/g e QP de 0,65 g/L.h em HHBM não destoxificado. Realizouse ensaios para avaliação do efeito do ácido acético sobre a fermentação em meio semissintético por P. stipitis, empregando-se as condições de pH e X0 otimizadas em HHBM não destoxificado (modelo 1) e destoxificado (modelo 2). Este estudo mostrou que nas condições do modelo 1, o ácido acético favoreceu a bioconversão sendo os melhores resultados obtidos na presença deste ácido (YP/S = 0,47 g/g e QP = 1,08 g/L.h). Por outro lado, nas condições do modelo 2, os valores de YP/S foram similares, enquanto que com a adição de ácido acético ao meio de fermentação, o valor de QP foi reduzido em 53%. Na fermentação em biorreator, o emprego das condições otimizadas em frascos (pH 6,4 e 5,0 g/L de células) resultaram em valores de QP 48% inferiores ao obtido em frascos (0,65 para 0,44 g/L.h), entretanto YP/S foi apenas 10% inferior (0,41 para 0,37 g/g). No presente estudo, conclui-se que a suplementação nutricional do HHBM e a otimização das condições de pH e X0 resultaram em valores promissores para os principais parâmetros da fermentação por P. stipitis, ressaltando o potencial deste hidrolisado em processos biotecnológicos para produção de etanol. / This study aimed to evaluate the ethanol production by Pichia stipitis in brewer\'s spent grain hemicellulosic hydrolysate (BSGHH). Initially, the effect of nutritional supplementation was evaluated by adding rice bran extract, urea and yeast extract. The results showed that supplementation only with yeast extract promoted the highest conversion values (YP/S = 0.44 g/L) and ethanol productivity (QP = 0.33 g/L.h). Additional assays showed that the optimal concentration of this nutrient was 3.0 g/L. To acclimate the cells to inhibitors present in BSGHH the yeast was cultivated in hydrolysate after growth for 24 hours in semisynthetic medium. This study resulted in increased of the process rates, 16% of the ethanol productivity (QP) and 10% on the substrate consumption (QS) when compared to growing cells only in the semisynthetic medium. In the second step a 22 full factorial centeredface design was employed to optimized the conditions of pH and initial cells concentration (X0) in fermentation of hydrolysate undetoxified and after detoxification with activated charcoal. Mathematical models that relate the YP/S and QP were obtained. For non-detoxified BSGHH (model 1) the optimal conditions of pH (6.4) and X0 (5.0 g/L) showed values parameters of 0.41 g/g and 0.65 g/L.h, respectively. In detoxified BSGHH (model 2) the optimum conditions of pH (6.0) and X0 (1.36 g/L), resulted in YP/S and QP values of 0.40 g/g and 0.46 g/L.h, respectively. Under these conditions, the the validity of the models were confirmed. The effect of acetic acid on fermentation by P. stipitis in semisynthetic medium, employing optimized conditions of pH and X0 in model 1 and model 2 was evaluated. The results showed that under the conditions of model 1 and in a concentration of 2,9 g/L, the acetic acid favored the bioconversion by P. stipitis, increasing the YP/S (15 %) and QP (66 %). On the other hand, in the conditions of the model 2 the YP/S values were similar, whereas the QP values were reduced by 53% when the acetic acid was added. By using these optimized conditions in bioreactor fermentation it was obtained the ethanol productivity was approximately 48% lower (0.65 to 0.44 g/L.h), however the ethanol production was similar as compared to fermentation flasks. It is possible conclude that the HHBSG requires nutritional supplementation and that the optimized conditions of pH and initial cells concentration can be used as a strategy in order to raising the fermentation parameters.

O presente trabalho se propôs a avaliar o efeito de uma etapa de tratamento alcalino no bagaço de malte visando à extração de acetato e de compostos fenólicos, e como consequência diminuir a concentração destes no hidrolisado hemicelulósico. Foi ainda objetivo deste trabalho, estudar o efeito do tratamento alcalino na bioconversão das frações celulósica e hemicelulósica do bagaço de malte, por meio de fermentação com as leveduras Kluyveromyces marxianus e Pichia stipitis, respectivamente. Os resultados mostraram que para todas as condições de tratamento alcalino avaliadas, ocorreu solubilização de acetato, compostos fenólicos e furanos, não sendo observada solubilização de açúcares. A capacidade de solubilização destes compostos aumentou com o aumento da concentração de hidróxido de sódio empregada até o tempo de 40 min, sendo observada uma concentração máxima de 0,86 g/L, 13,0 g/L e 0,58 g/L empregando 1%%, 2% e 2% de NaOH, respectivamente. Para todas as condições avaliadas, o tratamento alcalino do bagaço de malte reduziu a concentração de ácido acético no hidrolisado hemicelulósico. A menor concentração (0,026 g/L) foi obtida após 20 minutos de tratamento com 2% de NaOH. Com relação à concentração xilose, o menor teor desta pentose (8,3 g/L) foi obtido após o tratamento do bagaço com 0,25 % de NaOH por 2 minutos e o maior (22,0 g/L) com 0,5% de NaOH por 60 minutos. Visando estabelecer as condições de tratamento alcalino que permitissem uma redução na concentração de ácido acético, concomitantemente ao favorecimento da solubilização de xilose no hidrolisado hemicelulósico e de glicose no hidrolisado celulósico, as condições de temperatura e concentração de NaOH do tratamento alcalino do bagaço de malte foram otimizadas através de um planejamento estatístico. Nas condições otimizadas (concentração de NaOH de 0,63%, temperatura de 67,6°C e tempo de 20 min), o tratamento alcalino do bagaço de malte promoveu uma redução de 90% na concentração de ácido acético, concomitante ao aumento de 4,5% e 15% na concentração de xilose no hidrolisado hemicelulósico e concentração de glicose no hidrolisado celulósico, respectivamente. Os resultados referentes à bioconversão da fração celulósica demonstraram que para ambas as configurações de processo avaliadas (SHF e SSF) a fermentação da celulignina do material tratado (CLT) forneceu maior concentração de etanol, e essa diferença foi mais pronunciada na SSF. Além disso, na SSF, a produtividade volumétrica total em etanol, a qual considera o tempo de sacarificação e fermentação no processo foi aumentada em 2,2 vezes em relação à SHF. Com relação a bioconversão da hemicelulose, os resultados mostraram que tanto para o hidrolisado do bagaço referência não tratado (HHR) quanto para o previamente tratado com álcali (HHT), a concentração máxima de etanol foi obtida após 89 horas de fermentação, porém na fermentação do (HHT) a produção de etanol foi cerca de 3 vezes superior a obtida no (HHR), passando de 5,8 para 17,4 g/L. Com base nos resultados obtidos, pode-se concluir que a etapa de tratamento alcalino do bagaço de malte, provavelmente promoveu mudanças estruturais na celulignina aumentando a liberação de glicose no hidrolisado e ainda foi capaz de remover substâncias inibidoras do metabolismo microbiano, especialmente o ácido acético, favorecendo o processo fermentativo da fração hemicelulósica. / This study aimed to evaluate the effect of alkaline treatment in brewer\'s spent grain on extraction of acetate and phenolic compounds, and consequently to decrease their levels on hemicellulosic hydrolyzate. In addition, the effect of the alkali treatment on the bioconversion of cellulose and hemicellulose hydrolyzates employing Kluyveromyces marxianus and Pichia stipitis, respectively, was also evaluated. The results showed that for all conditions of treatment studied occurred solubilization of acetate, phenolics and furans, but not sugars. The solubilizing capacity of these compounds increased with increasing concentration of sodium hydroxide employed until the time of 40 min, and the maximum concentration observed was 0.86 g / L 13.0 g / L and 0.58 g / L from 1%, 2% NaOH and 2%, respectively. For all conditions evaluated, alkali treatment of brewer\'s spent grain reduced the acetic acid concentration in hemicellulosic hydrolyzate. The lowest concentration (0.026 g / L) was obtained after 20 minutes with 2% NaOH. With respect to xylose concentration, the lower content of this pentose (8.3 g / L) was obtained after the treatment with 0.25% NaOH for 2 minutes and the highest (22.0 g / L) with 0.5 % NaOH for 60 minutes. To establish optimal conditions of temperature and NaOH concentration in the alkaline treatment aiming to decrease the concentration of acetic acid and, at the same time, increase the solubilization of xylose in the hemicellulose hydrolyzate and glucose in the cellulosic hydrolyzed, a statistical design was used. Under optimized conditions (NaOH concentration of 0.63%, a temperature of 67.6 °C and time of 20 min) alkaline treatment of the brewer\'s spent grain promoted a decrease of 90% in acetic acid concentration, concomitant to an increase of 4.5% and 15% on xylose concentration in the hemicellulose hydrolyzate and on glucose concentration in the cellulosic hydrolyzate, respectively. The results concerning the bioconversion of cellulosic fraction showed that for both configurations of the process evaluated (SHF and SSF) the treated material cellulignin (CLT) provided higher ethanol concentration, and this difference was more pronounced in SSF. In addition, in SSF, the total ethanol volumetric productivity, which considers time saccharification and fermentation process was increased by 2.2 times compared to SHF. In relation to the hemicellulose bioconversion, the results showed that for both hydrolyzate employed, i.e untreated (HHR) and previously treated with alkali (HHT), the maximum ethanol concentration was achieved after 89 hours of fermentation, however the ethanol production in HHT was about 3 times higher obtained in HHR (from 5.8 to 17.4 g/L). Based on these results, we conclude that the alkali treatment, probably induced structural changes in the fraction of cellulignin regarding glucose released in the hydrolyzate and still was able to remove substances inhibitory to microbial metabolism, especially acetic acid, favoring the fermentation of hemicellulose fraction.

Quando um país se torna auto-suficiente em uma parte do ciclo nuclear, quanto à produção de combustível que será usado em suas centrais nucleares para a geração de energia, precisa voltar sua atenção para a melhor forma de armazenar este combustível após a sua utilização. A armazenagem do combustível nuclear queimado é uma prática necessária e utilizada nos dias atuais em todo o mundo como temporária, tanto por países que não têm definido o plano de destinação final, isto é, o repositório definitivo, como também por aqueles que já o possuem. Existem dois aspectos principais que envolvem os combustíveis queimados: um referente à armazenagem do combustível nuclear queimado destinado ao reprocessamento e o outro ao que será enviado para deposição final quando o sítio de deposição definitiva estiver definido, corretamente localizado, adequadamente caracterizado quanto aos diversos aspectos técnicos, e licenciado. Este último aspecto pode envolver décadas de estudos por causa das definições técnicas e normativas em um dado país. No Brasil, o interesse está voltado para a armazenagem dos combustíveis queimados que não serão reprocessados. Este trabalho analisa os tipos possíveis de armazenagem, o panorama internacional e a possível proposta para a futura construção de um sítio de armazenagem temporária no país. / When a country becomes self-sufficient in part of the nuclear cycle, as production of fuel that will be used in nuclear power plants for energy generation, it is necessary to pay attention for the best method of storing the spent fuel. Temporary storage of spent nuclear fuel is a necessary practice and is applied nowadays all over the world, so much in countries that have not been defined their plan for a definitive repository, as well for those that already put in practice such storage form. There are two main aspects that involve the spent fuels: one regarding the spent nuclear fuel storage intended to reprocessing and the other in which the spent fuel will be sent for final deposition when the definitive place is defined, correctly located, appropriately characterized as to several technical aspects, and licentiate. This last aspect can involve decades of studies because of the technical and normative definitions at a given country. In Brazil, the interest is linked with the storage of spent fuels that won't be reprocessed. This work analyses possible types of storage, the international panorama and a proposal for future construction of a spent nuclear fuel temporary storage place in the country.

Este trabalho tem como objetivo comparar a eficiência dos gastos públicos com saúde dos municípios brasileiros, ou seja, analisar quais deles melhor aproveitam seus recursos investidos nessa área. Em outras palavras, foi comparado o orçamento público total para este setor em cada município, com a qualidade da saúde da sua população - com o cuidado de levar em consideração uma série de outras variáveis que tem impacto sobre a saúde da população, tais como a educação, as condições de saneamento, a renda média, etc. Para tanto, primeiro foi feita uma caracterização geral da qualidade de saúde da população dos municípios, e depois foi construída uma fronteira de possibilidades de produção, utilizando-se da técnica de análise de Fronteiras Estocásticas, sendo a ineficiência dos municípios comparada através da distância de cada um deles em relação a essa fronteira. Foram analisados também fatores que pudessem explicar a magnitude relativa das ineficiências, na tentativa de encontrar variáveis que expliquem desempenhos melhores e piores, como por exemplo: a intensidade de utilização do capital, que se mostrou negativamente correlacionada com a ineficiência; a cobertura dos programas Saúde da Família e Agentes Comunitários da Saúde, que aparentemente não aumentam a eficiência; a parceira com o setor privado, entre outros. Os gastos avaliados são referentes ao período entre 1997 e 2000 anos que antecedem o Censo de onde foram tiradas as principais informações de saúde da população. A fonte utilizada para a obtenção dos dados de gastos com saúde foi o Sistema de Informações Financeiras (SIAFI) do Tesouro Nacional, por isso a amostra de municípios se constitui de todos os municípios brasileiros cujo montante de gastos com saúde no período em questão está discriminado nesse banco de dados1. A amostra final contempla 3370 municípios, número que corresponde a 60% do total nacional. / The aim of this work is to compare the efficiency of the public expenses with health among Brazilian municipalities, i.e. analyze which municipality better applied the financial resources on this sector. In order to achieve this goal, each municipalitys total public budget for this sector was compared to the local health quality of population taken into account variables that may affect populations health, such as: education; public utilities; average income; etc. Firstly, the general quality of health for the municipalities was defined and characterized, secondly a Production Possibility Frontier was built, using the method of Stochastic Frontier, where the municipalities inefficiency is compared through the distance of each of them to the frontier. The influence of some factors were tested, as they may explain the difference in performance among the municipalities. The main factors are: intensiveness of capital usage, which showed negative correlation with inefficiency; coverage of the public policies Saúde da Família and Agentes Comunitários da Saúde, which did not present evidences of raising the efficiency; private sector partnerships; among others. The database used was the Sistema de Informações Financeiras (SIAFI), collected from the National Treasury of Brazil, covering the period from 1997 to 2000. The populations data used was from the National Census of 2000. The final sample contains 3370 municipalities, which correspond to 60% out of the Brazilian total municipalities.