[pt] As atividades realizadas em estruturas Onshore e Offshore, relacionadas a exploração e produção de petróleo estão associadas ao risco iminente de vazamento de gás ou óleo, que encontrando qualquer tipo de ignição, pode causar incêndios e explosões com o potencial de causar perdas financeiras substanciais e mortes. No presente trabalho, a metodologia em CFD foi utilizada para analisar o vazamento de gás natural em um ponto localizado no módulo de compressão de gás em uma plataforma offshore. A turbulência do escoamento foi modelada com a metodologia RANS, empregando o modelo de duas equações K-epsilon. Considerando a situação crítica, o vazamento foi analisado em regime permanente, e modelado como uma fonte pontual. Foram consideradas duas intensidades de vento: 0,5 m/s representando a condição de calmaria e 6,5 m/s representando a velocidade mais frequente, e uma única direção no sentido PROA-POPA. Para cada condição de vento, foram estudadas quatro direções de vazamentos distintos (direção de liberação do gás), ou seja, a partir da junção entre o bocal do compressor e o flange da tubulação de alimentação do sistema (localizados imediatamente acima do compressor) tem-se vazamentos nas direções norte, sul, leste e oeste. A partir dos resultados de sobrepressão (DeltaP) (diferença entre a pressão ambiente (P0) e a pressão máxima de onda de choque (Pmáxima) obtida, pontos críticos foram identificados. O volume da nuvem foi determinado para cada cenário e, posteriormente, um cálculo de TNT equivalente (comparação do potencial da mistura explosiva com a massa de TNT necessária para produzir efeitos semelhantes) foi realizado para identificação dos potenciais riscos a estrutura offshore em caso de ignição do material gasoso disperso. Os resultados obtidos coincidiram com medidas experimentais de sobre pressão em situações semelhantes. Identificou-se como o pior cenário, vazamento no flange do compressor na direção sul, correspondente a direção contraria ao vento, com alta concentração de gás natural numa grande região da plataforma. / [en] Oil exploration and production activities in Onshore and Offshore structures are associated with the imminent risk of gas or oil leakage, which encountering any type of ignition, can cause fires and explosions with the potential to cause substantial financial losses and deaths. In the present work, the CFD methodology was used to analyze the leakage of natural gas at a point located in the gas compression module on an offshore platform. The flow turbulence was modeled with the RANS methodology, using the two-equation K-epsilon model. Consider the critical situation, the leak was analyzed in steady state, and modeled as a point source. Two wind intensities were considered: 0.5 m / s represents the calm condition and 6.5 m / s represents the most frequent speed, and a single direction in the PROA-POPA direction. For each wind condition, four distinct leakage results (direction of gas release) were studied, i.g., from the junction between the compressor nozzle and the system supply piping flange (driven above the compressor) there are leaks in the north, south, east and west directions. From the results of overpressure (deltaP) (the difference between the ambient pressure (P0) and the maximum shock wave pressure (P maximum) obtained, points obtained were separated. The cloud volume was determined for each scenario and, subsequently, a calculation of equivalent TNT (comparison of the potential of the explosive mixture with the mass of TNT necessary to produce similar effects) was performed to identify potential risks to the offshore structure in case of ignition make dispersed gaseous material. The results obtained coincided with experimental pressure measurements under similar conditions. It was identified as the worst scenario, a leak in the compressor flange in the south direction, corresponding to the direction against the wind, with a high concentration of natural gas in a large region of the platform.

Plantea evaluar levaduras, aisladas de ambientes mineros, con posible uso potencial en la degradación del TNT. Para ello, un total de 29 cepas de levaduras fueron seleccionadas para la evaluación de tolerancia frente a TNT; de las cuales 5 cepas no manifestaron cambios en el crecimiento celular en concentraciones altas de TNT de hasta en 1500 mg/L, más si un cambio en el patrón morfológico (levadura-hifa-pseudohifa). Luego, las levaduras seleccionadas fueron caracterizadas molecularmente, mediante la amplificación y secuenciación de la región D1/D2 del gen LSU 28S rDNA. A partir del análisis bioinformático y filogenético confirmamos la identidad de las cepas 8TS-500Z, MD3-S1, MD10-A1 y MD10-A3 como Candida orthopsilosis, Candida maltosa, Candida maltosa y Debaryomyces hansenii, respectivamente. Posteriormente, se realizó la evaluación de cada cepa de levadura en la degradación de TNT, como única fuente de nitrógeno, monitoreando la degradación de TNT, el crecimiento celular y la liberación de nitrito. Las cepas Debaryomyces hansenii MD10-A3 y Candida maltosa MD3-S1 lograron valores superiores en el porcentaje de remoción, 71.1±0.5 % y 67.7±2.6 %, respectivamente. Mientras que, las cepas Candida maltosa MD10-A1, Yarrowia lipolytica 9TS-500-1 y Candida orthopsilosis 8TS-500Z presentaron porcentajes de 57±4.1 %, 52.6±1.2 % y 47.4±3.1 %, a correspondencia, durante 84 h de incubación. El análisis de las constantes de velocidad de reacción (k) mediante modelos cinéticos de primer y segundo orden, la tasa específica de crecimiento (μ) y concentración de nitrito liberado durante la remoción de TNT a las 84 h de incubación, identificaron a la cepa Debaryomyces hansenii MD10-A3 como la mejor en eliminación máxima de TNT; debido a una mayor constante de velocidad de reacción k1=0.0159 ± 0.0012 h-1 (r2=0.9735) y crecimiento μ = 0.0136 ± 0.0025 h-1 (r2=0.8724); además de presentar la concentración más alta de nitrito de 2.5 ± 0.18 mg/L a las 84 h de incubación. Después, se utilizó un diseño factorial fraccionado 25-1, para evaluar qué factores influyen en la eficiencia de degradación de TNT por la cepa Debaryomyces hansenii MD10-A3 Los factores seleccionados fueron: glucosa (2.52 - 7.56 g/L), NH4Cl (0 - 0.2 g/L), tween 80 (0.1 - 0.5 %), inóculo inicial (0.3 - 0.7 DO) y pH (4.5 - 7.5). Los análisis ANOVA mostraron como los factores más influyentes, en el porcentaje de remoción de TNT, a glucosa, NH4Cl y pH con valores-P < 0.05. Además, se encontró que el efecto de estos factores en la remoción de TNT puede expresarse adecuadamente mediante un modelo polinómico de primer orden (r2 = 0.998). Finalmente, se validó el modelo determinado en condiciones óptimas, logrando un incremento en la eficiencia de remoción de hasta un 140 % a las 24 horas; además de incrementar su constante de velocidad de remoción en un 132.5 % (k1 = 0.0379). / Tesis

AN ANALYSIS OF GLOBAL GENE EXPRESSION RESULTING FROM EXPOSURE TO ENERGETIC MATERIALS A Dissertation Presented for the Doctor of Philosophy Degree University of Tennessee, Knoxville VERNON LASHAWN MCINTOSH JR. August 2010 Dedication This dissertation is dedicated to my family. My mother and father Debra and Vernon McIntosh instilled in me the respect for academic excellence and the drive maximize my potential. Early on, my younger brother Kyle started showing signs of a shared interest in biology thus my desire to be a positive role model for him kept me motivated. Last but certainly not least, my loving wife and best friend Nichole has been there to offer love and support throughout my entire undergraduate and graduate degrees. It’s difficult to imagine making it this far without her (and that’s not just because she paid the bills). Abstract Characteristic transcriptional biomarkers have been identified for microbial cultures exposed to 2, 4, 6-trinitrotoluene (TNT), 2, 6-dinitrotoluene (DNT), or triacetone-triperoxide (TATP). This study describes the generation of expression profiles for exposure to each compound, the functional significance of each response, and the identification of the characteristic alterations in gene expression associated with exposure to each compound. Expression profiles were generated from a total of three different candidate organisms: Escherichia coli, Saccharomyces cerevisiae, and Pseudomonas putida. Common to all three organisms, TNT exposure resulted in increased expression of genes involved in toxin resistance and drug efflux systems. The S.cerevisiae and E.coli expression profiles were both characterized by increased expression of genes involved in iron-sulfur cluster assembly, sulfur containing amino acids, sulfate transport and assimilation and the metabolism of nitrogen compounds. Only E.coli and Saccharomyces were used to generate DNT induced expression profiles; both profiles exhibited high degrees of similarity with each organism’s respective TNT profiles. This was especially true of the E.coli profile where 25 of the 30 alterations were also observed after exposure to TNT. A computational discriminant functional analysis was performed to identify characteristic biomarkers for each exposure. For each compound a set of transcriptional biomarkers (10 or less) was developed. An additional set of biomarkers was developed encompassing both TNT and DNT exposure. These sets of genes serve as a transcriptional fingerprint for exposure to each respective compound. The sensitivity and specificity of each transcriptional fingerprint is sufficient to correctly identify exposure to energetic materials against a background of non-energetic compound exposures. This study makes several novel contributions to the greater body of scientific knowledge: • This is the first documented study of the interactions of TATP in any biological system. • This is the first comprehensive gene expression study of the TNT response by P. putida, E.coli or E.coli. • This is the first application of computational class prediction in the development of biomarkers for exposure to energetic materials

Thesis (Ph. D.)--Mississippi State University. Department of Chemical Engineering. / Title from title screen. Includes bibliographical references.

Thesis (Ph.D.)--Civil and Environmental Engineering, Georgia Institute of Technology, 2008. / Committee Chair: Dr. Joseph B. Hughes; Committee Member: Dr. Jian Luo; Committee Member: Dr. Jim C. Spain; Committee Member: Dr. Patricia Sobecky; Committee Member: Dr. Spyros G. Pavlostathis

Thesis--Copenhagen. / Errata slip inserted. Includes indexes. Includes bibliographical references (v. 2, p. 173-197).

Thesis--Copenhagen. / Errata slip inserted. Includes indexes. Includes bibliographical references (v. 2, p. 173-197).

There is an alarming increase of explosions with devastating consequences, the ultimate being loss of life. Furthermore, these kinds of substances have a toxic effect on animals, nature and humans if they are incorrectly disposed. In order to counteract the rising trend and increase the feeling of security within the society, the Swedish Defense Research Agency (FOI) has started a new project which in the future might be used by the police in order to prevent possible terrorist attacks. The aim with this new project is to perform trace analysis of explosives in wastewater in order to receive an indication of where illegal production of explosives takes place. This method has the potential to be used for other matrixes, such as soil instead of wastewater or other water matrixes, thereby exposing possible harmful and contaminated places.   The aim with this thesis was to develop a method for an Ultra-High-Performance Liquid Chromatography (UHPLC) instrument in order to perform trace analysis of explosives in wastewater. Furthermore, the aim was also to develop a method for an automated solid phase extraction (SPE) instrument for sample clean-up. Lastly mass spectrometry was performed with a triple-quadrupole. A performance analysis was made for the developed UHPLC-method which resulted in a good repeatability. Furthermore, several experiments were conducted on the SPE-instrument in order to receive a yield close to 100%. The different experiments included comparison between the most beneficial eluent, volume of eluent and evaporation step. The highest yield was received with 3 ml acetonitrile without any evaporation step. A performance analysis was made of the developed method for the SPE-robot, which resulted in a good accuracy and precision. In hopes of lowering the detection limit, mass spectrometry was conducted by a preciously validated instrument based at FOI. A lower detection limit was received for all substances; R-salt 0,025 µg/ml, TNT 0,094 µg/ml and PETN 0,103 µg/ml.

TNT (2,4,6-trinitrotoluene) is a persistent contaminant at many military installations and poses a threat to aquatic ecosystems. Data from environmental fate and toxicity studies with TNT revealed that sediment toxicity test procedures required modification to accurately assess sediment TNT toxicity. Key modifications included aging TNT-spiked sediments 8-14 d, basing lethal dose on measured sediment concentrations of the molar sum of TNT and its main nitroaromatic (NA) transformation products (SNA), basing sublethal dose on average sediment SNA concentrations obtained from integration of sediment SNA transformation models, avoiding overlying water exchanges, and minimizing toxicity test durations. Solid phase microextraction fibers (SPMEs) were investigated as a biomimetic chemical measure of toxicity and bioavailability. Both organism and SPME concentrations provided measures of lethal dose independent of exposure scenario (TNT-spiked sediment or TNT-spiked water) for Tubifex tubifex. Among all benthic organisms tested (Chironomus tentans, Ceriodaphnia dubia, T. tubifex) and matrixes, median lethal dose (LC50) estimates based on SPME and organism concentrations ranged from 12.6 to 55.3 mmol SNA/ml polyacrylate and 83.4 to 172.3 nmol SNA/g tissue, ww, respectively. For Tubifex, LC50s (95% CI) based on SNA concentrations in sediment and SPMEs were 223 (209-238) nmol SNA/g, dw and 27.8 (26.0-29.8) mmol SNA/ml, respectively. Reproductive effects occurred at slightly lower exposures. Median effective dose (EC50) estimates (95% CI) for Tubifex cocoon production, based on sediment and SPME concentrations, were 118 (114-122) nmol SNA/g, dw and 21.8 (21.2-22.4) mmol SNA/ml, respectively. Bioconcentration experiments with Tubifex revealed that compound hydrophobicity predicted the toxicokinetics and bioconcentration of these compounds from water, however, there was a large discrepancy between the toxicokinetics of absorbed versus metabolically-generated aminodinitrotoluenes. A large portion of bioconcentrated, radiolabeled TNT transformation products could not be identified. In addition to their ability to provide matrix-independent measures of dose, SPME concentrations were more accurate indicators of bioavailable NAs than were sediment concentrations.

<p>Explosives and rocket fuel are just two prime examples of energetic materials, compounds that contain a combustible fuel and oxidizer within the same substance. Recent advances have enabled the construction of energetic materials through multiple variations of additive manufacturing, principally inkjet, direct-write, fused filament fabrication, electrospray deposition, and stereolithography. Many of the methods used for creating multiple layered objects (three-dimensional) from energetic materials involve the use of highly viscid materials.</p> <p>The focus of this work was to design a process capable of additively manufacturing three-dimensional objects from melt-castable energetic materials, which are known for their low viscosity. An in-depth printer design and fabrication procedure details the process requirements discovered through previous works, and the adaptations available and used to construct an additive manufacturing device capable of printing both energetic and non-energetic (also referred to as inert) melt-castable materials. Initial characterization of three proposed inert materials confirmed their relative similarity in rheological properties to melt-castable energetic materials and were used to test the printer’s performance.</p> <p>Preliminary tests show the constructed device is capable of additively manufacturing melt-castable materials reproducibly in individual layers, with some initial successful prints in three-dimensions, up to three layers. An initial characterization of the printer’s deposition characteristics additionally matches literature predictions. With the ability to print three-dimensional objects from melt-castable materials confirmed, future work will focus on the reproducibility of multi-layered objects and the refined formulation of melt-castable energetic materials.</p>