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Perchlorate ion interferes with thyroid function by competitively inhibiting the sodium-iodide symporter, thus blocking iodide uptake into the thyroid gland. In this study, the effect of perchlorate exposure on thyroid function and thyroid-responsive gene expression were examined in (1) embryos from eggs laid by perchlorate-treated Japanese quail hens and (2) perchlorate-treated young Japanese quail. I hypothesized that perchlorate exposure would decrease thyroid function and that the consequent hypothyroidism would alter the expression of thyroid sensitive genes. Laying Japanese quail hens were treated with 2000 mg/l and 4000 mg/l ammonium perchlorate in drinking water. Eggs from these hens were incubated. Embryos, exposed to perchlorate in the egg, were sacrificed at day 14 of the 16.5 day incubation period. Japanese quail chicks, 4-5 days old, were treated with 2000 mg/l ammonium perchlorate in drinking water for 2 and 7.5 weeks. Thyroid status was evaluated by measuring plasma thyroid hormone concentrations, thyroid gland weight and thyroidal thyroid hormone storage. Expression of thyroid-responsive genes was evaluated by measuring the mRNA levels of Type 2 deiodinase (D2) in the brain and liver, RC3/neurogranin mRNA level in the brain and Spot 14 mRNA level in the liver. Maternal perchlorate exposure led to embryonic hypothyroidism, demonstrated by thyroid hypertrophy and very low embryonic thyroidal TH storage. Embryonic hypothyroidism decreased body growth and increased D2 mRNA level in the liver (a presumed compensatory response to hypothyroidism) but did not affect the mRNA levels of D2 and RC3 in the brain. Spot 14 mRNA was not detected in embryonic liver. In the second part of the study, quail chicks showed early signs of hypothyroidism after two weeks of 2000 mg/l ammonium perchlorate exposure; plasma concentration and thyroid gland stores of both T4 and T3 were significantly decreased. After 7.5 weeks of perchlorate exposure, all thyroid variables measured indicated that the chicks had become overtly hypothyroid. D2 mRNA level was increased, a compensatory response to hypothyroidism, and spot 14 mRNA level was decreased, a substrate-driven response in the liver of quail chicks after two weeks of perchlorate exposure. However, no difference was observed in the mRNA levels of D2 and spot 14 in the liver after 7.5 weeks of perchlorate exposure, suggesting there was some adaptation to the hypothyroid condition. The mRNA level of D2 and RC3 in the brain was not affected by perchlorate-induced hypothyroidism in quail chicks after either 2 or 7.5 weeks of perchlorate exposure. As in the embryos, this suggests the brain of chicks was "protected" from the hypothyroid body conditions. / Ph. D.

O objetivo do trabalho foi demonstrar que o polivinilcarbazol (PVK) dopado com Perclorato de Lítio (LiClO4) pode converter energia luminosa em energia elétrica. Esse material polimérico possui a propriedade de absorver e gerar pares de elétron-lacunas fornecendo uma corrente elétrica quando exposto à iluminação. Para essa finalidade foi construído um dispositivo (célula solar) com a seguinte estrutura: vidro / ITO / a-Si:H (p) / polímero PVK / µ-Si:H (n) / Al, tendo o PVK dopado como camada ativa. O estudo proposto, dessa maneira, teve como finalidade: pesquisar, desenvolver, fabricar e caracterizar esse dispositivo, analisando suas características elétricas e ópticas, sua eficiência de conversão (rendimento) e outros fatores relacionados ao seu desempenho e do processo de fabricação. / The objective of this article is to demonstrate that the Poly(N-vinylcarbazole) PVK dumped with lithium perchlorate (LiClO4) can transform solar energy to electrical energy. This polymer material has the property of absorbing and generate electron hole pairs, providing an electric current when exposed to enlightenment. To achieve that, a solar cell has been constructed with the follow structure: glass structure/ITO/a-Si:H (p)/polymer PVK/µ-Si:H (n)/Al, with the PVK working as active layer. This proposed article had the objective to research, develop, construct and characterize this device, analyzing its electrical and optical characteristics, efficiency and other topics related to its development and construction process.

O objetivo do trabalho foi demonstrar que o polivinilcarbazol (PVK) dopado com Perclorato de Lítio (LiClO4) pode converter energia luminosa em energia elétrica. Esse material polimérico possui a propriedade de absorver e gerar pares de elétron-lacunas fornecendo uma corrente elétrica quando exposto à iluminação. Para essa finalidade foi construído um dispositivo (célula solar) com a seguinte estrutura: vidro / ITO / a-Si:H (p) / polímero PVK / µ-Si:H (n) / Al, tendo o PVK dopado como camada ativa. O estudo proposto, dessa maneira, teve como finalidade: pesquisar, desenvolver, fabricar e caracterizar esse dispositivo, analisando suas características elétricas e ópticas, sua eficiência de conversão (rendimento) e outros fatores relacionados ao seu desempenho e do processo de fabricação. / The objective of this article is to demonstrate that the Poly(N-vinylcarbazole) PVK dumped with lithium perchlorate (LiClO4) can transform solar energy to electrical energy. This polymer material has the property of absorbing and generate electron hole pairs, providing an electric current when exposed to enlightenment. To achieve that, a solar cell has been constructed with the follow structure: glass structure/ITO/a-Si:H (p)/polymer PVK/µ-Si:H (n)/Al, with the PVK working as active layer. This proposed article had the objective to research, develop, construct and characterize this device, analyzing its electrical and optical characteristics, efficiency and other topics related to its development and construction process.

Realizaram-se estudos potenciostáticos e potenciodinâmicos do comportamento eletroquímico do estanho em meio ácido de perclorato de sódio desaerado, com adições sistemáticas de ácido cítrico. Paralelamente aos ensaios eletroquímicos acompanhou-se o estado superficial do eletrodo com microscópio de luz refletida e microscópio eletrônico de varredura (SEM). Foi constatada, inicialmente, a ocorrência da redução do perclorato em presença do eletrodo de estanho. A redução do perclorato de sódio 0,5 M no eletrodo de estanho ocorre durante catodizações em meio ácido, no intervalo de potenciais de -0,7 V a -1,3 V; sendo que a presença do óxido facilita a redução. A geração de CI- deve ocorrer após a redução do cloreto básico de estanho. A presença do ácido cítrico reduz, mas não inibe completamente, a formação de cloreto, e causa a formação de uma camada de óxido que contém átomos de estanho e cloro. O potencial crítico de corrosão foi determinado em meio de perclorato de sódio 0,5 M, no intervalo de pH de 1,0 a 4,0. Os resultados obtidos mostraram que o tipo de corrosão depende do pH. Em pH 3,0 e 4,0, a formação de pite é antecedida pela formação de uma camada de óxido, que pode ser descrita por um modelo de dissolução-precipitação. A nucleação e o crescimento dos pites envolvem uma série de contribuições de corrente: corrente de formação do óxido, corrente de nucleação instantânea e corrente de nucleação progressiva. A formação dos pites, em pH=4,0, ocorre em duas etapas: nucleação instantânea tridimensional seguida de crescimento controlado por difusão hemisférica (nucleação progressiva). A presença de cloreto agrava a corrosão do estanho com e sem a presença de ácido cítrico. A concentração mínima do ácido orgânico para inibir a corrosão por pite do estanho em CIO4- 0,5 M é de 10-2 M, para o intervalo de pH estudado. A influência de adições sistemáticas de ácido cítrico no perfil potenciodinâmico do estanho foi observada. A concentração mínima do ácido orgânico para modificar a curva I/E do estanho em CIO4- 0,5 M é de 10-2 M, para o intervalo de pH estudado. A presença do ácido orgânico causa a formação de óxidos mais estáveis que são detectados em dois picos de corrente. No primeiro ocorre a oxidação de espécies adsorvidas de acordo com o modelo de Srinivasan e Gileadi. No segundo, ocorre a oxidação de espécies em solução onde a formação do filme pode ser descrita pelo modelo de Muller e Calandra. / Potentiodynamic and potentiostatic studies of the electrochemical behaviour of tin in sodium perchlorate deaerated, with and without citric acid, were carried out. Besides the electrochemical experiments, the electrode surface was investigated by scanning electron microscopy (SEM) and by a metallographic microscope. The electrochemistry of tin in sodium perchlorate has been found unexpectediy to be complicated by the reduction of the perchlorate anion. The reduction process has been shown to take place through a potential region comprising the negative side of the double layer region and the positive side of the hydrogen region (-0,7 V ≤ E ≤ -1,3 V). The presence of oxide on the electrode surface favours the reduction. The reduction may occur in two steps: the formation of basic tin chloride followed by its reduction, producing CI-. The presence of citric acid reduces, but don\'t inhibits completely, the formation of chloride, during reduction, and induces the growth of an oxide layer which contains Sn and CI atoms. The breakdown potential was determined in sodium perchlorate 0,5 M in the pH range from 1,0 to 4,0. The results showed that the type of corrosion - pitting or general corrosion - depends on pH. At pH 3,0 and 4,0 the pit initiation is preceeded by the formation of an oxide layer, described by a dissolution-precipitation model for metal passivation. Pit nucleation and growth involve a number of contributions which were distinguished through the analysis of current transients at constant potentials. At pH 4,0, pit growth occurs in two steps and can, in principie, be described by instantaneous nucleation followed by progressive nucleation. The inhibiting effect of citric acid on pitting corrosion is recognized by the shift of the breakdown potentials to more positive values. The minimum concentration of the organic acid to inhibit pitting of tin is 10-2 M. The influence of systematic additions of citric acid on the potentiodynamic profile of tin in NaCIO4 0,5 M was observed. The minimun concentration of the organic acid to change the I/E curves is 10-2 M, in the pH range from 1,0 to 4,0. The scan rate dependence in the potential region of formation and reduction of the film showed that in a first stage adsorption occurs, according to Srinivasan and Gileadi\'s model. In the second stage, the v1/2 dependence found can be explained by ohmic resistance control, on the basis of Muller\'s passivation model.

Laboratory and field studies were completed to characterize the geochemistry and microbiology of drainage emanating from low-S content waste-rock test piles at the Diavik Diamond Mine (Diavik) from 2007 through 2010. The potential use of small-scale laboratory humidity-cell experiments to predict the water quality from larger-scale field-based experiments also was examined. Waste rock at Diavik is segregated into three categories according to sulfide content: Type I (target concentration: < 0.04 wt. % S), Type II (target concentration: 0.04 to 0.08 wt. % S) and Type III (target concentration: > 0.08 wt. % S). Four high-density polyethylene tanks, 2 m in diameter by 2 m in height, were filled with and surrounded by waste rock (active zone lysimeters; AZLs) at the Diavik site to study the upper 2 m of the active zone within a waste-rock pile and to evaluate the quality of effluent released from waste rock with differing S contents (Type I AZLs: 0.014 wt. % S and Type III AZLs: 0.035 wt. % S). In addition, three waste-rock test piles also were constructed at Diavik, two uncovered test piles (Type I test pile: 0.035 wt. % S and Type III test pile: 0.053 wt. % S) and a third pile was constructed based on the mine-closure plan which consists of waste rock (Type III: 0.082 wt. % S) capped with a 1.5 m layer of till and a 3 m layer of Type I material (Covered test pile). Each test pile is underlain by a high-density polyethylene geomembrane that captures and directs water to outflow drains. Results show that the release and transport of blasting residuals could be used as a resident tracer, indicating the first flush of water through the AZLs and the test piles. Variations in concentrations of blasting residuals and the gradual rate of dissipation provide an indication of the heterogeneity of the distribution of blasting residuals and the relative contributions of water and solutes from different flow paths. As temperatures within the test piles increase in response to ambient air temperature increases, larger proportions of the test pile contributed to the outflow, and increased concentrations of blasting residuals were observed in waste-rock test pile effluent. Effluent from the Type I AZLs and test pile maintained near-neutral pH (ranged from 5.8 to 8) with concentrations of SO₄²⁻ < 500 mg L⁻¹. These results suggest that the near-neutral pH values were associated with the presence of carbonates in the waste rock and the lack of intense acid generation. As ambient air temperatures increased in spring and summer of each year, the measured pH in the Type III test-pile drainage decreased from near-neutral in May (pH 7.5) to acidic conditions by October (ranged from 5 to 4.5). As the pH in the Type III test pile decreased, concentrations of SO₄²⁻ and dissolved metals increased (e.g. SO₄²⁻ > 1500 mg L⁻¹) suggesting sulfide oxidation was occurring. Maximum concentrations of SO₄²⁻, Al, Zn, Ni, Co, and Cu were observed in 2009 during the first flush of water through the Type III test pile. A sequence of acid-neutralization reactions was inferred based on the water chemistry of the effluent derived from the Type III AZLs and waste-rock test pile. This acid-neutralization sequence is similar to those observed at other AMD impacted sites. A series of mineral dissolution-precipitation reactions controlled pH and metal mobility; carbonate-mineral dissolution consumed H⁺ generated from sulfide-mineral oxidation at near neutral pH and the dissolution of Al and Fe (oxy)hydroxides consumed H⁺ at pH < 5.0. The cover system on the Covered test pile dampened the effects of ambient air temperature on the internal temperatures within the core of the Covered test pile. As a result, the Covered test pile had a relatively steady change in flow rate, with decreased flow from June to August, which led to a slow but prolonged release of sulfide-mineral oxidation products, such as SO₄²⁻ and dissolved metals, including Ni, Co, Zn, Cd, and Cu, compared to the uncovered Type III test pile. The pH decreased in 2008 and remained low for the duration of the study, whereas the pH in the uncovered test pile was near-neutral at the beginning of each field season in May and decreased to < 4.2 by the end of the field season in November. The microbiological-community profiles observed in the AZLs and waste-rock test piles suggest typical AMD-related species were present in acidic effluent with elevated concentrations of metals, whereas typical soil microbes were present in effluent with a near-neutral pH and lower concentrations of SO₄²⁻ and dissolved metals. The Type III AZLs, Type III test pile, and Covered test pile maintained populations of acidophilic Fe-oxidizers, whereas, the Type I AZLs and Type I test pile maintained populations of neutrophilic S-oxidizers. Laboratory humidity-cell (1 kg) results were scaled up to estimate the water quality from the Type III AZLs (6 t) using measured physical and chemical parameters. The results suggested over-prediction of SO₄²⁻ and metal concentrations when low mean annual precipitation occurred, limiting flushing of predicted oxidation products. In subsequent years with higher mean annual precipitation oxidation products from previous years were liberated and resulted in the under prediction of SO₄²⁻ and metal concentrations. Additionally, Fe and Al were over-predicted because Fe and Al concentrations in the AZL effluent may be controlled by the solubility and formation of secondary minerals, such as Fe oxyhydroxides, jarosite, and goethite, which were not included in the scaling procedure.

Laboratory and field studies were completed to characterize the geochemistry and microbiology of drainage emanating from low-S content waste-rock test piles at the Diavik Diamond Mine (Diavik) from 2007 through 2010. The potential use of small-scale laboratory humidity-cell experiments to predict the water quality from larger-scale field-based experiments also was examined. Waste rock at Diavik is segregated into three categories according to sulfide content: Type I (target concentration: < 0.04 wt. % S), Type II (target concentration: 0.04 to 0.08 wt. % S) and Type III (target concentration: > 0.08 wt. % S). Four high-density polyethylene tanks, 2 m in diameter by 2 m in height, were filled with and surrounded by waste rock (active zone lysimeters; AZLs) at the Diavik site to study the upper 2 m of the active zone within a waste-rock pile and to evaluate the quality of effluent released from waste rock with differing S contents (Type I AZLs: 0.014 wt. % S and Type III AZLs: 0.035 wt. % S). In addition, three waste-rock test piles also were constructed at Diavik, two uncovered test piles (Type I test pile: 0.035 wt. % S and Type III test pile: 0.053 wt. % S) and a third pile was constructed based on the mine-closure plan which consists of waste rock (Type III: 0.082 wt. % S) capped with a 1.5 m layer of till and a 3 m layer of Type I material (Covered test pile). Each test pile is underlain by a high-density polyethylene geomembrane that captures and directs water to outflow drains. Results show that the release and transport of blasting residuals could be used as a resident tracer, indicating the first flush of water through the AZLs and the test piles. Variations in concentrations of blasting residuals and the gradual rate of dissipation provide an indication of the heterogeneity of the distribution of blasting residuals and the relative contributions of water and solutes from different flow paths. As temperatures within the test piles increase in response to ambient air temperature increases, larger proportions of the test pile contributed to the outflow, and increased concentrations of blasting residuals were observed in waste-rock test pile effluent. Effluent from the Type I AZLs and test pile maintained near-neutral pH (ranged from 5.8 to 8) with concentrations of SO₄²⁻ < 500 mg L⁻¹. These results suggest that the near-neutral pH values were associated with the presence of carbonates in the waste rock and the lack of intense acid generation. As ambient air temperatures increased in spring and summer of each year, the measured pH in the Type III test-pile drainage decreased from near-neutral in May (pH 7.5) to acidic conditions by October (ranged from 5 to 4.5). As the pH in the Type III test pile decreased, concentrations of SO₄²⁻ and dissolved metals increased (e.g. SO₄²⁻ > 1500 mg L⁻¹) suggesting sulfide oxidation was occurring. Maximum concentrations of SO₄²⁻, Al, Zn, Ni, Co, and Cu were observed in 2009 during the first flush of water through the Type III test pile. A sequence of acid-neutralization reactions was inferred based on the water chemistry of the effluent derived from the Type III AZLs and waste-rock test pile. This acid-neutralization sequence is similar to those observed at other AMD impacted sites. A series of mineral dissolution-precipitation reactions controlled pH and metal mobility; carbonate-mineral dissolution consumed H⁺ generated from sulfide-mineral oxidation at near neutral pH and the dissolution of Al and Fe (oxy)hydroxides consumed H⁺ at pH < 5.0. The cover system on the Covered test pile dampened the effects of ambient air temperature on the internal temperatures within the core of the Covered test pile. As a result, the Covered test pile had a relatively steady change in flow rate, with decreased flow from June to August, which led to a slow but prolonged release of sulfide-mineral oxidation products, such as SO₄²⁻ and dissolved metals, including Ni, Co, Zn, Cd, and Cu, compared to the uncovered Type III test pile. The pH decreased in 2008 and remained low for the duration of the study, whereas the pH in the uncovered test pile was near-neutral at the beginning of each field season in May and decreased to < 4.2 by the end of the field season in November. The microbiological-community profiles observed in the AZLs and waste-rock test piles suggest typical AMD-related species were present in acidic effluent with elevated concentrations of metals, whereas typical soil microbes were present in effluent with a near-neutral pH and lower concentrations of SO₄²⁻ and dissolved metals. The Type III AZLs, Type III test pile, and Covered test pile maintained populations of acidophilic Fe-oxidizers, whereas, the Type I AZLs and Type I test pile maintained populations of neutrophilic S-oxidizers. Laboratory humidity-cell (1 kg) results were scaled up to estimate the water quality from the Type III AZLs (6 t) using measured physical and chemical parameters. The results suggested over-prediction of SO₄²⁻ and metal concentrations when low mean annual precipitation occurred, limiting flushing of predicted oxidation products. In subsequent years with higher mean annual precipitation oxidation products from previous years were liberated and resulted in the under prediction of SO₄²⁻ and metal concentrations. Additionally, Fe and Al were over-predicted because Fe and Al concentrations in the AZL effluent may be controlled by the solubility and formation of secondary minerals, such as Fe oxyhydroxides, jarosite, and goethite, which were not included in the scaling procedure.

Realizaram-se estudos potenciostáticos e potenciodinâmicos do comportamento eletroquímico do estanho em meio ácido de perclorato de sódio desaerado, com adições sistemáticas de ácido cítrico. Paralelamente aos ensaios eletroquímicos acompanhou-se o estado superficial do eletrodo com microscópio de luz refletida e microscópio eletrônico de varredura (SEM). Foi constatada, inicialmente, a ocorrência da redução do perclorato em presença do eletrodo de estanho. A redução do perclorato de sódio 0,5 M no eletrodo de estanho ocorre durante catodizações em meio ácido, no intervalo de potenciais de -0,7 V a -1,3 V; sendo que a presença do óxido facilita a redução. A geração de CI- deve ocorrer após a redução do cloreto básico de estanho. A presença do ácido cítrico reduz, mas não inibe completamente, a formação de cloreto, e causa a formação de uma camada de óxido que contém átomos de estanho e cloro. O potencial crítico de corrosão foi determinado em meio de perclorato de sódio 0,5 M, no intervalo de pH de 1,0 a 4,0. Os resultados obtidos mostraram que o tipo de corrosão depende do pH. Em pH 3,0 e 4,0, a formação de pite é antecedida pela formação de uma camada de óxido, que pode ser descrita por um modelo de dissolução-precipitação. A nucleação e o crescimento dos pites envolvem uma série de contribuições de corrente: corrente de formação do óxido, corrente de nucleação instantânea e corrente de nucleação progressiva. A formação dos pites, em pH=4,0, ocorre em duas etapas: nucleação instantânea tridimensional seguida de crescimento controlado por difusão hemisférica (nucleação progressiva). A presença de cloreto agrava a corrosão do estanho com e sem a presença de ácido cítrico. A concentração mínima do ácido orgânico para inibir a corrosão por pite do estanho em CIO4- 0,5 M é de 10-2 M, para o intervalo de pH estudado. A influência de adições sistemáticas de ácido cítrico no perfil potenciodinâmico do estanho foi observada. A concentração mínima do ácido orgânico para modificar a curva I/E do estanho em CIO4- 0,5 M é de 10-2 M, para o intervalo de pH estudado. A presença do ácido orgânico causa a formação de óxidos mais estáveis que são detectados em dois picos de corrente. No primeiro ocorre a oxidação de espécies adsorvidas de acordo com o modelo de Srinivasan e Gileadi. No segundo, ocorre a oxidação de espécies em solução onde a formação do filme pode ser descrita pelo modelo de Muller e Calandra. / Potentiodynamic and potentiostatic studies of the electrochemical behaviour of tin in sodium perchlorate deaerated, with and without citric acid, were carried out. Besides the electrochemical experiments, the electrode surface was investigated by scanning electron microscopy (SEM) and by a metallographic microscope. The electrochemistry of tin in sodium perchlorate has been found unexpectediy to be complicated by the reduction of the perchlorate anion. The reduction process has been shown to take place through a potential region comprising the negative side of the double layer region and the positive side of the hydrogen region (-0,7 V &#8804; E &#8804; -1,3 V). The presence of oxide on the electrode surface favours the reduction. The reduction may occur in two steps: the formation of basic tin chloride followed by its reduction, producing CI-. The presence of citric acid reduces, but don\'t inhibits completely, the formation of chloride, during reduction, and induces the growth of an oxide layer which contains Sn and CI atoms. The breakdown potential was determined in sodium perchlorate 0,5 M in the pH range from 1,0 to 4,0. The results showed that the type of corrosion - pitting or general corrosion - depends on pH. At pH 3,0 and 4,0 the pit initiation is preceeded by the formation of an oxide layer, described by a dissolution-precipitation model for metal passivation. Pit nucleation and growth involve a number of contributions which were distinguished through the analysis of current transients at constant potentials. At pH 4,0, pit growth occurs in two steps and can, in principie, be described by instantaneous nucleation followed by progressive nucleation. The inhibiting effect of citric acid on pitting corrosion is recognized by the shift of the breakdown potentials to more positive values. The minimum concentration of the organic acid to inhibit pitting of tin is 10-2 M. The influence of systematic additions of citric acid on the potentiodynamic profile of tin in NaCIO4 0,5 M was observed. The minimun concentration of the organic acid to change the I/E curves is 10-2 M, in the pH range from 1,0 to 4,0. The scan rate dependence in the potential region of formation and reduction of the film showed that in a first stage adsorption occurs, according to Srinivasan and Gileadi\'s model. In the second stage, the v1/2 dependence found can be explained by ohmic resistance control, on the basis of Muller\'s passivation model.

This document details original numerical studies performed by the author pertaining to the propellant oxidizer, ammonium perchlorate (AP). Detailed kinetic mechanisms have been utilized to model the combustion of the monopropellants AP and ADN, and a two-dimensional diffusion flame model has been developed to examine the flame structure above an AP/HTPB composite propellant. This work was part of an ongoing effort to develop theoretically based, a priori combustion models. The improved numerical model for AP combustion utilizes a “universal” gas-phase kinetic mechanism previously applied to combustion models of HMX, RDX, GAP, GAP/RDX, GAP/HMX, NG, BTTN, TMETN, GAP/BTTN, and GAP/RDX/BTTN. The universal kinetic mechanism has been expanded to include chlorine reactions, thus allowing the numerical modeling of AP. This is seen as a further step in developing a gas-phase kinetic mechanism capable of modeling various practical propellants. The new universal kinetic mechanism consists of 106 species and 611 reactions. Numerical results using this new mechanism provide excellent agreement with AP's burning rate, temperature sensitivity, and final species data. An extensive literature review has been conducted to extract experimental data and qualitative theories concerning ADN combustion. Based on the literature review, the first numerical model has also been developed for ADN that links the condensed and gas phases. The ADN model accurately predicts burning rates, temperature and species profiles, and other combustion characteristics of ADN at pressures below 20 atm. Proposed future work and modifications to the present model are suggested to account for ADN's unstable combustion at pressures between 20 and 100 atm. A two-dimensional model has been developed to study diffusion in composite propellant flames utilizing a vorticity formulation of the transport equations. This formulation allows for a more stable, robust, accurate, and faster solution method compared to the Navier-Stokes formulations of the equations. The model uses a detailed gas-phase kinetic mechanism consisting of 37 species and 127 reactions. Numerical studies have been performed to examine particle size, pressure, and formulation effects on the flame structure above an AP/HTPB propellant. The modeled flame structure was found to be qualitatively similar to the BDP model. Results were consistent with experimental observations. Three different combustion zones, based on particle size and pressure, were predicted: the AP monopropellant limit, the diffusion flame, and a premixed limit. Mechanistic insights are given into AP's unique combustion properties.

This dissertation documents the building of computational propellant/ingredient models toward predicting AP/HTPB/Al cookoff events. Two computer codes were used to complete this work; a steady-state code and a transient ignition code Numerous levels of verification resulted in a robust set of codes to which several propellant/ingredient models were applied. To validate the final cookoff predictions, several levels of validation were completed, including the comparison of model predictions to experimental data for: AP steady-state combustion, fine-AP/HTPB steady-state combustion, AP laser ignition, fine-AP/HTPB laser ignition, AP/HTPB/Al ignition, and AP/HTPB/Al cookoff. A previous AP steady-state model was updated, and then a new AP steady-state model was developed, to predict steady-state combustion. Burning rate, temperature sensitivity, surface temperature, melt-layer thickness, surface species at low pressure and high initial temperature, final flame temperature, final species fractions, and laser-augmented burning rate were all predicted accurately by the new model. AP ignition predictions gave accurate times to ignition for the limited experimental data available. A previous fine-AP/HTPB steady-state model was improved to predict a melt layer consistent with observation and avoid numerical divergence in the ignition code. The current fine-AP/HTPB model predicts burning rate, surface temperature, final flame temperature, and final species fractions for several different propellant formulations with decent success. Results indicate that the modeled condensed-phase decomposition should be exothermic, instead of endothermic, as currently formulated. Changing the model in this way would allow for accurate predictions of temperature sensitivity, laser-augmented burning rate, and surface temperature trends. AP/HTPB ignition predictions bounded the data across a wide range of heat fluxes. The AP/HTPB/Al model was based upon the kinetics of the AP/HTPB model, with the inclusion of aluminum being inert in both the solid and gas phases. AP/HTPB/Al ignition predictions bound the data for all but one source. AP/HTPB/Al cookoff predictions were accurate when compared to the limited data, being slightly low (shorter time) in general. Comparisons of AP/HTPB/Al ignition and cookoff data showed that the experimental data might be igniting earlier than expected.