No description available.

This thesis discusses findings gained through work with the NOx abatement system at Radford Facility and Army Ammunition Plant (RFAAP). Removal of harmful substances from flue-gas emissions has garnered increased priority in the chemical industry in preceding decades, as governmental restrictions on these substances become more stringent and as national awareness concerning environmental quality and resource utilization continues to grow. These reasons make the study of NOx abatement an important and challenging endeavor. This work concerns itself specifically with reduction of NOx in flue-gas emissions from stationary sources. First we present an overview of current technology and approaches to controlling NOx for stationary sources. Next, we focus in on one particular approach to control of NOx within the context of a case study of the technology used at the Radford Facility and Army Ammunition Plant. RFAAP employs a scrubber/absorber tower followed in series by a selective catalytic reduction (SCR) reaction vessel in their NOx abatement system. We use as the method of study computer simulations within ASPEN Plus, a process simulation software package for chemical plants. We develop three different models with which to characterize NOx abatement at RFAAP, a conversion model, an equilibrium model and a kinetic model. The conversion-reaction model approximates the absorption and SCR reactions with constant percentage extent-of-reaction values. Though useful for initial investigation and mass balance information, we find the conversion model's insensitivity to process changes to be unacceptable for in-depth study of the case of NOx absorption and SCR. The equilibrium-reaction model works on the assumption that all the reactions reach chemical equilibrium. For the conditions studied here, we find the equilibrium model accurately simulates NOx absorption but fails in the case of SCR. Therefore, we introduce a kinetic-reaction model to handle the SCR. The SCR reactions prove to be highly rate-dependant and the kinetic approach performs well. The final evolution of the ASPEN Plus simulation uses an equilibrium model for the absorption operation and a kinetic model for the SCR. We explore retrofit options using this combined model and propose process improvements. We end this work with observations of the entire project in the form of conclusions and recommendations for improving the operation of the NOx abatement system through process-parameter optimization and equipment-retrofit schemes. By leading the reader through the process by which we arrived at a successful and highly informative computer model for NOx absorption and SCR, we hope to educate the reader on the subtleties of NOx abatement by absorption and SCR. We attempt to break down the numerous complex processes to present a less daunting prospect to the engineer challenged with the application of current NOx removal technology. In addition, we introduce the reader to the power and usefulness of computer modeling in instances of such complexity. The model teaches us about the details of the process and helps us develop concrete information for its optimization. Ideally, the reader could use a similar approach in tackling related operations and not confine the usefulness of this thesis to NOx absorption and SCR. The audiences that we think would benefit from exposure to this thesis are the following: • Environmental engineers with a NOx problem; • Process engineers interested in optimization tools; • Design engineers exploring flue-gas treatment options; • Combustion engineer desiring to learn about SCR; • Chemists and mathematicians intrigued by the complexities of NOx absorption chemistry. / Master of Science

Syftet med arbetet var att samla in mätdata för att kontrollera luftkvalitén ombord på två svenska fartyg, för att sedan jämföra resultaten med Arbetsmiljöverkets hygieniska gränsvärden och den svenska normalbefolkningens exponering för olika ämnen. Resultatet från studien var också tänkt att vara till hjälp för att utforma nya råd och rekommendationer för att minimera exponeringen och även till att bidra med material för fler framtida studier. Under cirka en vecka ombord på fartygen samlades data in med hjälp av passiva provtagare för att registrera halter av bensen, kvävedioxid och polycykliska aromatiska kolväten. Resultaten visade att luftkvalitén ombord på de två fartygen generellt sett är god. Samtliga uppmätta halter låg långt under Arbetsmiljöverkets gränsvärden och det skiljde sig inte mycket varken mellan fartyg eller jämfört med den svenska normalbefolkningens exponering. Därför är inte svensk sjömän ombord på svenskflaggade fartyg i större fara för toxiska luftföroreningar ombord jämfört med när de är hemma. / The main purpose of this study was to measure and evaluate the air quality onboard two Swedish ships, and compare the results with the exposure limits laid out by the Swedish Work Environment Authority (Arbetsmiljöverket) and the Swedish population’s exposure to various substances. The results of this study were also meant to be helpful to form new advice and recommendations to minimize exposure and also to provide material for future studies. During approximately one week onboard the two ships data were collected using passive samplers to register levels of benzene, nitrogen dioxide and polycyclic aromatic hydrocarbons. The results indicated that the air quality onboard the two ships were generally good. All measured concentrations were well below safety applications and it did not differ very much neither between ships nor compared with the Swedish population’s exposure. In conclusion, Swedish sailors onboard Swedish ships are not in greater danger of toxic air pollutants onboard compared to when they are at home.

Introdução: A poluição do ar pode levar a alterações no sistema respiratório, especialmente entre certos grupos, como as gestantes, que são mais vulneráveis aos efeitos de poluentes atmosféricos. A gravidez é um período que envolve alterações funcionais e anatômicas no corpo da mulher, incluindo alterações na função pulmonar, o que pode ser avaliado por espirometria, um método simples, barato e eficaz. Objetivos: Os objetivos deste estudo foram a usar a espirometria para avaliar a função pulmonar de mulheres no primeiro trimestre (T1) e no terceiro trimestre (T3) de gravidez e analisar a influência da exposição a poluição do ar sobre os parâmetros espirométricos. Metodologia: O estudo foi realizado no Ambulatório de Obstetrícia do Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo (HCFMUSP) entre Maio de 2011 e Agosto de 2013. Foram aplicados os seguintes critérios de inclusão: gestação única, idade gestacional no dia da primeira espirometria inferior a 13,86 semanas, ausência de doenças maternas préexistentes, preparação adequada para o teste de espirometria e amostradores passivos individuais (APIs) adequados para análise. Os critérios de exclusão foram a mudança de endereço, o aborto, o teste de espirometria inadequado e desistência de participar do projeto. Os APIs contendo dois filtros de celulose embebidos com solução absorvente para capturar os níveis de NO2 e outros dois filtros embebidos com solução de índigo blue para medir os níveis de O3 foram entregues às gestantes cerca de 12 dias antes da realização do teste de espirometria. Dados do relatório anual da Companhia Ambiental do Estado de São Paulo (CETESB) para o mesmo período dos amostradores passivos, foram utilizados. Para a espirometria, um espirômetro Koko foi utilizado, sendo considerada as duas melhores curvas para avaliar os resultados da função pulmonar. Análise estatística: Foi utilizado o teste Mann-Whitney para grupos independentes e Wilcoxon para os dependentes. Devido à pequena variação na exposição à poluição, a exposição no primeiro trimestre (Q1) e quarto trimestre (Q4) foram comparados para cada poluente em T1 e T3 através da análise nãoparamétrica para medidas repetidas. Resultados: Houve uma redução estatisticamente significativa dos valores absolutos (T1: 3,690 L; T3: 3,475 L) e preditos (T1: 101%, T3: 97,5%) da capacidade vital forçada (CVF), p < 0,0001. E uma redução estatisticamente significativa dos valores absolutos (T1: 3.080 L; T3: 2.950 L) e preditos (T1: 99%, T3: 96%) do volume expiratório forçado no primeiro segundo do procedimento (FEV1), p < 0,0001. A exposição à poluição foi semelhante em ambos os trimestres, exceto para a exposição de NO2 no API, o que foi inferior em T3 (p = 0,001). Independentemente do trimestre (T1 ou T3), o grupo de mulheres do Q4 (T1: 97,5%; T3: 98,5%) teve NO2 estatisticamente maior dos valores do fluxo expiratório forçado de 25 a 75% do procedimento (FEF25-75%) do que o grupo em Q1 (T1: 80%; T3: 92%). O grupo de mulheres do Q1 do NO2 teve um aumento significativo neste parâmetro de T1 a T3 (p = 0,042). Em termos de valores absolutos da relação FEV1/FVC, o grupo de mulheres no Q1 mostrou um aumento estatisticamente significativo neste parâmetro de T1 (0,810 L) para T3 (0,840 L) (p = 0,026). Em T3, os valores absolutos e relativos da CVF foram estatisticamente maiores para o grupo de gestantes do Q4 (3,535 L; 100,5%) de NO2 do que para o grupo de gestantes do Q1 (3,345 L; 92%). O grupo de gestantes do Q4 de O3 mostrou o VEF1 estatisticamente maior eno T1 (102,5%) do que no T3 (95,5%) (p < 0,001). Independentemente do trimestre, o grupo de gestantes do Q4 do MP10, teve valores absolutos da CVF (T1: 3.520 L; T3: 3,265 L) e os valores de VEF1 (T1: 2,915 L; T32.840 L) foram estatisticamente menor do que para o grupo em Q1 (FVC - T1: 3.780 L; T3: 3.580 L) (FEV1 - T1: 3.180 L; T3: 3.065 L) p = 0,040; p = 0,035, respectivamente. Valores absolutos e preditos do pico de fluxo expiratório (PEF) em T1 das mulheres do Q4 (5,995 L; 80%) do MP10 foram estatisticamente menores do que para as mulheres no Q1 (6,675 L; 85%) (p = 0,006; p = 0,041 , respectivamente). Mulheres grávidas em Q4 (0,835 L) do MP10 tiveram os valores da relação VEF1/CVF estatisticamente menores valores do que as mulheres do Q1 (0,850 L) (p = 0,029). Conclusão: Exposição a NO2 e O3 foi associada com o aumento de alguns dos parâmetros de espirometria, indicando a presença de uma possível função de defesa pulmonar ou mecanismo compensatório em mulheres grávidas, quando expostos a esses poluentes. O MP10 foi associado com a redução de alguns parâmetros de espirometria durante a gravidez, indicando os efeitos danosos do poluente para a função do pulmão de mulheres grávidas / Introduction - Air pollution can lead to alterations to the respiratory system, particularly among certain groups, such as pregnant women, which are more vulnerable to the effects of air pollutants. Pregnancy is a period involving functional and anatomical changes in a woman\'s body. These changes include pulmonary function, which can be assessed by spirometry, a simple, inexpensive and effective method. Objectives - The aims of this study were to use spirometry to evaluate pulmonary function in pregnant women in the first trimester (T1) and the third trimester (T3) of pregnancy and to analyze the influence of air pollution exposure on the spirometry parameters. Methodology - This study was carried out at the Obstetrics Clinic of Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo (HCFMUSP) between May 2011 and August 2013. The following inclusion criteria were applied: singleton pregnancy, 13.86 weeks gestational age at the first spirometry, no preexisting maternal diseases, adequate preparation for the spirometry test and individual passive samplers (IPAs) suitable for analysis. The exclusion criteria were change of address, abortion, inadequate spirometry testing and withdrawal from the project. The exposure to pollutants prior to the spirometry tests was assessed in T1 and T3. The passive samplers containing two cellulose filters soaked with absorbent solution to capture NO2 levels and two other filters soaked with indigo solution to measure O3 levels were provided to the pregnant women roughly 12 days prior to the spirometry test. Data from the environmental Company of São Paulo State (CETESB) annual report for the same period the passive samplers were used. For the spirometry, a Koko spirometer was used, taking the two best curves to assess lung function results. Statistical Analysis - We used Mann- Whitney tests for independent groups and Wilcoxon for the dependent ones. Due to the small variation in the exposure to pollution, exposure in the first quarter (Q1) and fourth quarter (Q4) were compared for each pollutant in T1 and T3 through non-parametrical analysis for repeated measurements. Results - It has been noted a significant statistical reduction of absolute and predicted forced vital capacity (FVC) values (3.690 L; 3.475 L) and forced expiratory volume during the first second of the procedure (FEV1) (3.080 L; 2.950 L) from T1 to T3. Exposure to pollution was similar in both trimesters, except for exposure to NO2 in the passive sampler, which was lower in T3 (p = 0.001). Regardless of the trimester (T1 or T3), the group of pregnant women in Q4 (97.5%; 98.5%) of NO2 had statistically higher predicted forced expiratory values of 25 to 75% of the procedure (FEF25-75%) than the group in Q1 (80%; 92%). Pregnant women in Q1 of NO2 had a significant increase in this parameter from T1 to T3 (p = 0.042). In terms of absolute FEV1/FVC values, pregnant women in Q1 showed a statistically significant rise in this parameter from T1 (0.810 L) to T3 (0,840 L) (p = 0,026). In T3, absolute and predicted FVC values were statistically higher for the group of pregnant women in Q4 (3.535 L; 100.5%) of NO2 than for the group of pregnant women in Q1 (3.345 L; 92%). Pregnant women in Q4 of O3 displayed statistically higher FEV1 values in T1 (102.5%) than in T3 (95.5%) (p < 0.001). Regardless of trimester, for the group of pregnant women in Q4 of MP10, absolute FVC (T1:3 .520 L; T3: 3.265 L) and FEV1 values (T1: 2.915 L; T3: 2.840 L) were statistically lower than for the group in Q1 (FVC - T1: 3.780 L; T3: 3.580 L) (FEV1 - T1: 3.180 L; T3: 3.065 L) p = 0.040; p = 0.035 respectively. Absolute and predicted peak expiratory flow (PEF) in T1 of pregnant women in Q4 (5.995 L; 80%) of MP10 were statistically lower than for the pregnant women in Q1 (6.675 L; 85%) (p = 0.006; p = 0.041, respectively). Pregnant women in Q4 (0.835 L) of MP10 displayed statistically lower absolute FEV1/FVC values than the pregnant women in Q1 (0.850 L) (p = 0.029). Conclusion - Exposure to NO2 and O3 was associated with the increase in some of the spirometry parameters, indicating the presence of a possible lung function defense or compensatory mechanism in pregnant women when exposed to those pollutants. The MP10 was associated with the reduction of some spirometry parameters during pregnancy, indicating the harmful effects of that pollutant to the lung function of pregnant women

Introdução: A poluição do ar pode levar a alterações no sistema respiratório, especialmente entre certos grupos, como as gestantes, que são mais vulneráveis aos efeitos de poluentes atmosféricos. A gravidez é um período que envolve alterações funcionais e anatômicas no corpo da mulher, incluindo alterações na função pulmonar, o que pode ser avaliado por espirometria, um método simples, barato e eficaz. Objetivos: Os objetivos deste estudo foram a usar a espirometria para avaliar a função pulmonar de mulheres no primeiro trimestre (T1) e no terceiro trimestre (T3) de gravidez e analisar a influência da exposição a poluição do ar sobre os parâmetros espirométricos. Metodologia: O estudo foi realizado no Ambulatório de Obstetrícia do Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo (HCFMUSP) entre Maio de 2011 e Agosto de 2013. Foram aplicados os seguintes critérios de inclusão: gestação única, idade gestacional no dia da primeira espirometria inferior a 13,86 semanas, ausência de doenças maternas préexistentes, preparação adequada para o teste de espirometria e amostradores passivos individuais (APIs) adequados para análise. Os critérios de exclusão foram a mudança de endereço, o aborto, o teste de espirometria inadequado e desistência de participar do projeto. Os APIs contendo dois filtros de celulose embebidos com solução absorvente para capturar os níveis de NO2 e outros dois filtros embebidos com solução de índigo blue para medir os níveis de O3 foram entregues às gestantes cerca de 12 dias antes da realização do teste de espirometria. Dados do relatório anual da Companhia Ambiental do Estado de São Paulo (CETESB) para o mesmo período dos amostradores passivos, foram utilizados. Para a espirometria, um espirômetro Koko foi utilizado, sendo considerada as duas melhores curvas para avaliar os resultados da função pulmonar. Análise estatística: Foi utilizado o teste Mann-Whitney para grupos independentes e Wilcoxon para os dependentes. Devido à pequena variação na exposição à poluição, a exposição no primeiro trimestre (Q1) e quarto trimestre (Q4) foram comparados para cada poluente em T1 e T3 através da análise nãoparamétrica para medidas repetidas. Resultados: Houve uma redução estatisticamente significativa dos valores absolutos (T1: 3,690 L; T3: 3,475 L) e preditos (T1: 101%, T3: 97,5%) da capacidade vital forçada (CVF), p < 0,0001. E uma redução estatisticamente significativa dos valores absolutos (T1: 3.080 L; T3: 2.950 L) e preditos (T1: 99%, T3: 96%) do volume expiratório forçado no primeiro segundo do procedimento (FEV1), p < 0,0001. A exposição à poluição foi semelhante em ambos os trimestres, exceto para a exposição de NO2 no API, o que foi inferior em T3 (p = 0,001). Independentemente do trimestre (T1 ou T3), o grupo de mulheres do Q4 (T1: 97,5%; T3: 98,5%) teve NO2 estatisticamente maior dos valores do fluxo expiratório forçado de 25 a 75% do procedimento (FEF25-75%) do que o grupo em Q1 (T1: 80%; T3: 92%). O grupo de mulheres do Q1 do NO2 teve um aumento significativo neste parâmetro de T1 a T3 (p = 0,042). Em termos de valores absolutos da relação FEV1/FVC, o grupo de mulheres no Q1 mostrou um aumento estatisticamente significativo neste parâmetro de T1 (0,810 L) para T3 (0,840 L) (p = 0,026). Em T3, os valores absolutos e relativos da CVF foram estatisticamente maiores para o grupo de gestantes do Q4 (3,535 L; 100,5%) de NO2 do que para o grupo de gestantes do Q1 (3,345 L; 92%). O grupo de gestantes do Q4 de O3 mostrou o VEF1 estatisticamente maior eno T1 (102,5%) do que no T3 (95,5%) (p < 0,001). Independentemente do trimestre, o grupo de gestantes do Q4 do MP10, teve valores absolutos da CVF (T1: 3.520 L; T3: 3,265 L) e os valores de VEF1 (T1: 2,915 L; T32.840 L) foram estatisticamente menor do que para o grupo em Q1 (FVC - T1: 3.780 L; T3: 3.580 L) (FEV1 - T1: 3.180 L; T3: 3.065 L) p = 0,040; p = 0,035, respectivamente. Valores absolutos e preditos do pico de fluxo expiratório (PEF) em T1 das mulheres do Q4 (5,995 L; 80%) do MP10 foram estatisticamente menores do que para as mulheres no Q1 (6,675 L; 85%) (p = 0,006; p = 0,041 , respectivamente). Mulheres grávidas em Q4 (0,835 L) do MP10 tiveram os valores da relação VEF1/CVF estatisticamente menores valores do que as mulheres do Q1 (0,850 L) (p = 0,029). Conclusão: Exposição a NO2 e O3 foi associada com o aumento de alguns dos parâmetros de espirometria, indicando a presença de uma possível função de defesa pulmonar ou mecanismo compensatório em mulheres grávidas, quando expostos a esses poluentes. O MP10 foi associado com a redução de alguns parâmetros de espirometria durante a gravidez, indicando os efeitos danosos do poluente para a função do pulmão de mulheres grávidas / Introduction - Air pollution can lead to alterations to the respiratory system, particularly among certain groups, such as pregnant women, which are more vulnerable to the effects of air pollutants. Pregnancy is a period involving functional and anatomical changes in a woman\'s body. These changes include pulmonary function, which can be assessed by spirometry, a simple, inexpensive and effective method. Objectives - The aims of this study were to use spirometry to evaluate pulmonary function in pregnant women in the first trimester (T1) and the third trimester (T3) of pregnancy and to analyze the influence of air pollution exposure on the spirometry parameters. Methodology - This study was carried out at the Obstetrics Clinic of Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo (HCFMUSP) between May 2011 and August 2013. The following inclusion criteria were applied: singleton pregnancy, 13.86 weeks gestational age at the first spirometry, no preexisting maternal diseases, adequate preparation for the spirometry test and individual passive samplers (IPAs) suitable for analysis. The exclusion criteria were change of address, abortion, inadequate spirometry testing and withdrawal from the project. The exposure to pollutants prior to the spirometry tests was assessed in T1 and T3. The passive samplers containing two cellulose filters soaked with absorbent solution to capture NO2 levels and two other filters soaked with indigo solution to measure O3 levels were provided to the pregnant women roughly 12 days prior to the spirometry test. Data from the environmental Company of São Paulo State (CETESB) annual report for the same period the passive samplers were used. For the spirometry, a Koko spirometer was used, taking the two best curves to assess lung function results. Statistical Analysis - We used Mann- Whitney tests for independent groups and Wilcoxon for the dependent ones. Due to the small variation in the exposure to pollution, exposure in the first quarter (Q1) and fourth quarter (Q4) were compared for each pollutant in T1 and T3 through non-parametrical analysis for repeated measurements. Results - It has been noted a significant statistical reduction of absolute and predicted forced vital capacity (FVC) values (3.690 L; 3.475 L) and forced expiratory volume during the first second of the procedure (FEV1) (3.080 L; 2.950 L) from T1 to T3. Exposure to pollution was similar in both trimesters, except for exposure to NO2 in the passive sampler, which was lower in T3 (p = 0.001). Regardless of the trimester (T1 or T3), the group of pregnant women in Q4 (97.5%; 98.5%) of NO2 had statistically higher predicted forced expiratory values of 25 to 75% of the procedure (FEF25-75%) than the group in Q1 (80%; 92%). Pregnant women in Q1 of NO2 had a significant increase in this parameter from T1 to T3 (p = 0.042). In terms of absolute FEV1/FVC values, pregnant women in Q1 showed a statistically significant rise in this parameter from T1 (0.810 L) to T3 (0,840 L) (p = 0,026). In T3, absolute and predicted FVC values were statistically higher for the group of pregnant women in Q4 (3.535 L; 100.5%) of NO2 than for the group of pregnant women in Q1 (3.345 L; 92%). Pregnant women in Q4 of O3 displayed statistically higher FEV1 values in T1 (102.5%) than in T3 (95.5%) (p < 0.001). Regardless of trimester, for the group of pregnant women in Q4 of MP10, absolute FVC (T1:3 .520 L; T3: 3.265 L) and FEV1 values (T1: 2.915 L; T3: 2.840 L) were statistically lower than for the group in Q1 (FVC - T1: 3.780 L; T3: 3.580 L) (FEV1 - T1: 3.180 L; T3: 3.065 L) p = 0.040; p = 0.035 respectively. Absolute and predicted peak expiratory flow (PEF) in T1 of pregnant women in Q4 (5.995 L; 80%) of MP10 were statistically lower than for the pregnant women in Q1 (6.675 L; 85%) (p = 0.006; p = 0.041, respectively). Pregnant women in Q4 (0.835 L) of MP10 displayed statistically lower absolute FEV1/FVC values than the pregnant women in Q1 (0.850 L) (p = 0.029). Conclusion - Exposure to NO2 and O3 was associated with the increase in some of the spirometry parameters, indicating the presence of a possible lung function defense or compensatory mechanism in pregnant women when exposed to those pollutants. The MP10 was associated with the reduction of some spirometry parameters during pregnancy, indicating the harmful effects of that pollutant to the lung function of pregnant women

Pour répondre aux aspects essentiels du développement durable, les nouvelles constructions doivent réduire leur consommation énergétique. Cela se traduit par une meilleure isolation des bâtiments mais aussi par une maitrise et un control du renouvellement de l'air par ventilation mécanique contrôlée. De telles actions participent à l’augmentation des concentrations de polluants en intérieur pouvant avoir des conséquences sanitaires importantes. La technique de dépollution passive de l’air reposant sur des processus photocatalytiques est une solution intéressante pour répondre à cette problématique. L’objectif de cette étude est d’optimiser une peinture pour application intérieure contenant des nanoparticules de dioxyde de titane (TiO2) afin de réduire les concentrations de polluants gazeux comme de dioxyde d’azote (NO2) tout en limitant la formation de contaminants tel que l’acide nitreux (HONO). Dans cette optique, durant cette thèse, différents jeux de peintures (photocatalytiques et de référence) ont été étudiés dans des conditions simulées de laboratoire et dans un environnement réel. Les expériences en laboratoire ont montré une efficacité d’élimination du NO2 jusqu’à 4 fois plus importante sur une peinture photocatalytique que sur une peinture standard. Cette étude met également en évidence la formation hétérogène d’acide nitreux pendant la réaction photocatalysée du NO2. Les rendements de formation de HONO sont compris entre 4 et 20 % du NO2 consommé. Lors d’une étude à échelle 1, dans une pièce modèle, des concentrations significatives de HONO ont été mesurées. Ces observations mettent à jour des mécanismes encore non élucidés de formation de cette espèce en air / In order to improve building energy consumption, new constructions reduce air exchange rate by including better insulation and adding controlled ventilation. However, this energetic advantage participates in increasing the concentration of indoor pollutants and can be the cause of adverse effects on the occupants’ health. A possible solution to this issue is to use the photocatalysis principle/theory as an innovating technique for air remediation. The aim of this study is to optimize photocatalytic materials containing titanium dioxide (TiO2) in order to reduce the concentrations of indoor air pollutants such as nitrogen dioxide (NO2) without the generation of emerging contaminants such as nitrous acid HONO. Over the course of this Ph.D., effects of different photocatalytic paints, tested under simulated and real conditions were studied. Laboratory experiments showed an effective elimination of nitrogen dioxide (NO2) up to 4 times higher with a photocatalytic paint than with a standard paint, the most important parameters influencing NO2 elimination being nanoTiO2 quantity built-in the paint, light intensity, and temperature. This study also highlights the heterogeneous formation of nitrous acid (HONO) during the photocatalysis of NO2, reactivity yields range from 4 % to 20 % of used NO2. During a scale one study in a model room, a significant concentration of HONO was measured. Those observations reveal yet not fully elucidated mechanisms for the indoor formation of this compound

A base case modelling investigation was conducted to explore the chemical and physical behaviour of ground-level ozone (O3) and its precursor nitrogen dioxide (NO2) in Ontario using the U.S. Environmental Protection Agency (EPA) Community Multiscale Air Quality (CMAQ) model. Two related studies were completed to evaluate the performance of CMAQ in reproducing the behaviour of these species in both rural and urban environments by comparing to surface measurements collected by the Ontario Ministry of the Environment (MOE) network of air quality stations. The first study was a winter examination and the second study was conducted for a period during the summer of the same year. The municipality of North Bay was used to represent a rural setting given its smaller population relative to the city of Ottawa which was the base of the urban site. Statistical and graphical analyses were used to validate the model output. CMAQ was found to replicate the spatial variation of O3 and NO2 over the domain in both the winter and summer, but showed some difficulty in simulating the temporal allocation of the species. Validation statistics for North Bay and Ottawa showed overall O3 mean biases (MB) of 3.35 ppb and 2.25 ppb, respectively, and overall NO2 MB of -8.75 ppb and -4.37 ppb, respectively for the winter. Summer statistics generated O3 MB of 4.66 ppb (North Bay) and 10.05 ppb (Ottawa) while both MB for NO2 were between -2.20 ppb to -2.55 ppb. Graphical analysis showed that the model was not able to reproduce the lower levels of O3, especially at night, or the higher levels of NO2 during the day at the North Bay site for either season. This was expected since the comparisons were made between point measurements and 36 km grid-averaged model results. The presence of high amounts of NO2 emissions local to the monitoring sites compared to the levels represented in the emissions inventory may also be a contributing factor. The simulations for Ottawa demonstrated better agreement between model results and measurements as CMAQ provided a more accurate reproduction of both the higher and lower mixing ratios of O3 and NO2 during the winter and summer seasons. Results indicate that CMAQ is able to simulate urban environments better than rural ones.

Diss. (sammanfattning) Umeå : Umeå universitet, 2009. / Härtill 5 uppsatser. Även tryckt utgåva.

In this retrospective cohort from 2002 through 2007, 104,003 singleton live births in Hillsborough County, Florida were analyzed to elucidate the relationship between feto-infant morbidity outcomes and prenatal exposure to six criteria air pollutants. This study is based on three linked databases: The Florida Hospital Discharge database; The vital statistics records of singleton live births; Air Pollution meteorological data from the Environmental Protection Agency. There are six common air pollutants, particulate matter 2.5 (PM2.5), particulate matter 10 (PM10), ground-level ozone (O3), carbon monoxide (CO), nitrogen (NOx), and lead (Pb). These pollutants are harmful to human health and the environment. The primary outcomes of interest were low birth weight (LBW), preterm births, and small for gestational age (SGA). The intent of this project is to address these issues of air pollution effects and the methodology surrounding the study of air pollution. Using modeling, exposure values of the six criteria air pollutants were assigned to mothers over their period of pregnancy. To address these methodological concerns, this study utilizes the structural equation modeling, quartile groupings with dose response, and trimester groupings to evaluate the relationship between air pollution and birth outcomes of pregnant residents. Using structural equation modeling a significant B value of 0.35 indicated that exposure to the six criteria pollutant in pregnancy may have a significant relationship to all five birth outcomes if they are broken down into latent variables. Quartile data demonstrated that NOx seemed to have most significant associations with all outcomes with a dose response for SGA. PM10 and PM2.5 had some association to LBW and VLBW at high levels. PM10 demonstrated significance in the higher doses for SGA. However, the only dose response relationship that was demonstrated for PM10 and PM2.5 was in VLBW. PM10 also demonstrated a dose response with very preterm. If sub-divided into trimester data, PM10 demonstrated a significant relationship between exposures in all trimesters and LBW, VLBW, and SGA. PM2.5 demonstrated a significant relationship between exposures in all trimesters and VLBW. CO demonstrated a significant relationship in the 2nd trimester for LBW as well as for SGA. Mothers and their babies are a vulnerable population who are more susceptible to lower levels of pollution. These air pollutants can possibly have long-term effect on their children. Implantation of laws and regulations, warning system, or more strict EPA standards may be needed to adequately control the cost to our society.

A base case modelling investigation was conducted to explore the chemical and physical behaviour of ground-level ozone (O3) and its precursor nitrogen dioxide (NO2) in Ontario using the U.S. Environmental Protection Agency (EPA) Community Multiscale Air Quality (CMAQ) model. Two related studies were completed to evaluate the performance of CMAQ in reproducing the behaviour of these species in both rural and urban environments by comparing to surface measurements collected by the Ontario Ministry of the Environment (MOE) network of air quality stations. The first study was a winter examination and the second study was conducted for a period during the summer of the same year. The municipality of North Bay was used to represent a rural setting given its smaller population relative to the city of Ottawa which was the base of the urban site. Statistical and graphical analyses were used to validate the model output. CMAQ was found to replicate the spatial variation of O3 and NO2 over the domain in both the winter and summer, but showed some difficulty in simulating the temporal allocation of the species. Validation statistics for North Bay and Ottawa showed overall O3 mean biases (MB) of 3.35 ppb and 2.25 ppb, respectively, and overall NO2 MB of -8.75 ppb and -4.37 ppb, respectively for the winter. Summer statistics generated O3 MB of 4.66 ppb (North Bay) and 10.05 ppb (Ottawa) while both MB for NO2 were between -2.20 ppb to -2.55 ppb. Graphical analysis showed that the model was not able to reproduce the lower levels of O3, especially at night, or the higher levels of NO2 during the day at the North Bay site for either season. This was expected since the comparisons were made between point measurements and 36 km grid-averaged model results. The presence of high amounts of NO2 emissions local to the monitoring sites compared to the levels represented in the emissions inventory may also be a contributing factor. The simulations for Ottawa demonstrated better agreement between model results and measurements as CMAQ provided a more accurate reproduction of both the higher and lower mixing ratios of O3 and NO2 during the winter and summer seasons. Results indicate that CMAQ is able to simulate urban environments better than rural ones.