This study evaluated the performance of advanced oxidation processes that combines UV, O3 and H2O2 to mineralize N-methyl-2-pyrrolidinone (NMP) in an aqueous solution. As a photoresist stripper, NMP is widely used in the semi-conductor and optoelectronics industries, and difficult to be degraded by bio-treatment of wastewater. The concentration of total organic carbon (TOC) was selected as a mineralization index of the decomposition of NMP by the advanced oxidation process. Results of this study indicate that UV irradiation 37.2 mWcm−2 UV(254 nm) and O3 doses of 5¡Ñ10-4 mol/min causes the best 89% mineralization of NMP (20 mg/L) over a reaction time of 60 minitues and the the mineralization efficiency follows the sequence of UV/O3 (89%)¡ÖUV/H2O2/O3 (58%)¡ÖO3/H2O2 (48%)¡ÖO3 (42%)¡ÖUV/H2O2 (34%). The effect of the initial NMP concentration over the range of 20 to 80 mg/L on the mineralization rate of NMP was studied, and the experimental results indicates that the mineralization efficiency of NMP declines as the initial NMP concentration increases, the mineralization efficiencies were 89%¡B82%¡B61%¡B54% after a reaction time of 60 min. This result indicates that the photocatalytic mineralization of NMP by UV/O3 is not simple first-order but pseudo first-order. Since NMP generates organic acid compounds, which cannot easily be decomposed by hydroxide radicals (⋅OH ) before fully mineralization, a higher concentration of NMP results in a higher concentration of organic acid compounds. Hence, the mineralization rate of more highly concentrated NMP is lower. The pseudo first-order rate constant (kobs) is calculated between 0.0365~0.0127 min-1 and half-life (t1/2) between 18.99~54.58 minitues. The existence of the H2O2 may influence the NMP mineralization rate in the UV/O3 system, because H2O2 plays the role of initiator and scavenger at the same time. The experiment results inducate that as the concentration of H2O2 increases, the mineralization rate of NMP declines. In the UV/O3 system, the H2O2 consumed hydroxide radicals and acted as a scavenger of hydroxide radical. Adding H2O2 to the UV/O3 system has a negative effect of NMP mineralization. Adding ferrous ions is likely to reduce the mineralization rate of NMP, the mineralization efficiency reduces from 89% to 48% as the ferrous ions increses from 0 mg/L to 10 mg/L, because the ferrous ions in the solution are oxidized into the ferric hydroxide precipitate in a UV/O3 environment and produce turbidity in the reactor. This precipitation phenomenon somewhat obstructs the penetration of UV light. UV/O3 is less capable of mineralizing NMP. The presence of ferrous ions reduces the effectiveness of UV/O3 in mineralizing NMP. The result indicates that this pH range does not affect the mineralization process. The pseudo first-order rate constant (kobs) is calculated between 0.0349~0.0362 min-1 and half-life (t1/2) between 19.15~19.86 minitues over the range of pH:3.0 to pH:10.0 in the UV/O3 system. The pH values of the solution do not affect the mineralization efficiency of the UV/O3 process. The results also show that in highly SO42- and ClO4- ionic environment, NMP mineralization is not suppressed, indicating that a highly ionic environment does not negatively affect the generation of hydroxide radical by UV/O3 system.

Abstract Semiconductor and optoelectrical industries are among the major high-technological enterprises in Taiwan. Many nitrogen-containing compounds such as monoethanol amine (MEA), 1-methyl-2-pyrrolidinone (NMP), 1-amino-2-propyl alcohol (APA) and hexamethylene disilazane (HMDS) are used in both manufacturing processes. These compounds may release to environments from waste gas or water sources and become environmental pollutants if not properly treated. The main purpose of this research was to investigate the biodegradation characteristics of the four compounds. The research was performed by using a 5-L sequencing batch reactor operated at a cycling time of 24 hrs that included a filling time of 0.5 hr, an aeration and reaction time of 21 hrs, a setting time of 2 hrs, and a drawing time of 0.5 hr. The reaction conditions were as follows for the activated sludge in the reactor: MLSS (mixed liquor suspended solids) = 2000-3000 mg/L, pH = 6.8-7.2, aeration intensity = 0.46 L air/(L liquor. min), F/M (food-to-microorganism ratio) = 0.2-0.5 kg COD/(kg MLSS. Day), and C0 (initial concentration of the target compound in the mixed liquor) = 100-800 mg/L. Results demonstrate that above around 80% of all the four compounds were degraded within the aeration time of 21 hrs, and the organic nitrogen was converted to NH3-N, NO2¡Ð-N, NO3¡Ð-N, N2,and biomass-N. For MEA, above 10 % of the NH3-N hydrolyzed from the compound was nitrified for loadings of less than 0.05 kg MEA-N/m3.day, and no nitrification was observed for loadings of above 0.20 kg MEA-N/m3.day. Approximate 3% of MEA-N was converted to biomass-N and the average nitrogen content in the sludge was 4.25%. With regards to NMP, around 5, 73-83, and 14-24% of the nitrogen was converted to NH3-N+NO2¡Ð-N+NO3¡Ð-N, N2, and biomass-N, respectively, and the average nitrogen content in the sludge was 5.6%. As for the biodegradation of APA, there occurred a filamentous sludge-bulking phenomenon when C0 = 400 or 800 mg/L. With C0 increased from 200 to 800 mg/L, there was an increasing rate of ammonia formation and decreasing rate of nitrification. For the compound, around 9, 74, and 13% of the nitrogen was converted to NO2¡Ð-N, N2, and biomass-N, respectively, at a loading of 0.0358 kg APA-N/m3.day. The conversions became 12, 66, and26%, respectively, for NO2¡Ð-N, N2, and biomass-N with the loading increased to 0.0716 kg APA-N/m3.day. The average nitrogen content in the sludge was 4.9%. HMDS was biologically degraded in the emulsion state with the help of surfactants Tween 80 and Span 80. With C0 increased from 200 to 800 mg/L, there was an increasing nitrification rate and nearly constant ammonia nitrite formation rates. Above 90% of HMDS-N was converted to N2 and a few of it to biomass-N. The average nitrogen content in the sludge was around 4.5%.

No description available.

Au cours de ce travail de thèse, nous avons étudié la synthèse de particules de latex par polymérisation en miniémulsion, un procédé de polymérisation en milieu aqueux dispersé. Nous avons synthétisé avec succès et de manière contrôlée des particules de latex de polystyrène de masse molaire élevée (Mn > 30 000 g.mol-1) par polymérisation radicalaire contrôlée par les nitroxydes (NMP) en miniémulsion, en présence et en absence de tensio-actif moléculaire. Des latex stables présentant des diamètres de l’ordre de 150 – 200 nm ont été synthétisés. Une seconde partie de ce travail de thèse est dédié à la transposition de la polymérisation radicalaire contrôlée par les nitroxydes amorcée depuis la surface (« surface-initiated NMP ») d’un procédé en masse vers un procédé en milieu aqueux dispersé (miniémulsion) en vue de synthétiser des nanoparticules cœur@écorce de type silica@polystyrène. La dernière partie du travail de thèse est consacrée à la synthèse de stabilisants polymères et plus précisément à la synthèse de copolymères amphiphiles à base de dextrane ou de poly(acide acrylique) modifiés de manière hydrophobes par des terpènes. L’efficacité de stabilisation de tels copolymères synthétisés à partir de bio-resources a été étudiée au travers leur capacité à stabiliser la polymérisation en miniémulsion du styrène. Tout au long de ce travail, les caractéristiques macromoléculaires des polymères ainsi que la taille et la morphologie des particules ont été caractérisées respectivement par chromatographie d’exclusion stérique, diffusion dynamique de la lumière et microscopie (SEM, TEM, AFM). / During the work of this PhD, we investigated the synthesis of latex particles by miniemulsion, an aqueous dispersed medium process. We managed to synthesize in a controlled manner high molar mass (Mn > 30 000 g.mol-1) polystyrene latex particles via nitroxide mediated radical polymerization (NMP) in miniemulsion in both the presence and absence of molecular surfactant. Stable latex with final diameters within the range of 150-200 nm were synthesized. A second part of the PhD work was devoted to the transposition of surface-initiated NMP from bulk polymerization to polymerization in aqueous dispersed media (miniemulsion) in order to synthesize silica@polystyrene core@shell hybrid nanoparticles. The last part of the PhD work was dedicated to the synthesis of polymeric stabilizers, more precisely to the synthesis of amphiphilic copolymers based on dextran or poly(acrylic acid) polymers hydrophobically modified by terpenes. The stabilization efficiency of such copolymers synthesized from renewable resources to stabilize styrene miniemulsion polymerization was investigated. During this work, we characterized the macromolecular features of polymers along with the size and the morphology of the final particles by respectively size exclusion chromatography (SEC), dynamic light scattering (DLS) and microscopy (SEM, TEM, AFM).

Submitted by Luciana Ferreira (lucgeral@gmail.com) on 2016-08-05T13:14:47Z No. of bitstreams: 2 Dissertação - Verônica Vale Carvalho - 2016.pdf: 3350706 bytes, checksum: a2b65a96388e547cf16aa0fd45a20f7f (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2016-08-05T13:17:53Z (GMT) No. of bitstreams: 2 Dissertação - Verônica Vale Carvalho - 2016.pdf: 3350706 bytes, checksum: a2b65a96388e547cf16aa0fd45a20f7f (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2016-08-05T13:17:53Z (GMT). No. of bitstreams: 2 Dissertação - Verônica Vale Carvalho - 2016.pdf: 3350706 bytes, checksum: a2b65a96388e547cf16aa0fd45a20f7f (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2016-07-25 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / Heavy oil fractions studies are of great importance for the oil industry, receiving special attention in recent decades due to the interest to meet them in order to obtain compounds with higher added value derived from this. Moreover, these studies also aim solutions to the problems caused by these fractions during all processing steps oil. Asphaltenes in NMP produces two fractions, a soluble and the other insoluble in NMP. It was suggested that the NI fraction present low content of aromatic compounds, opening a new debate on the composition of asphaltenes which are widely discussed in the literature as aromatic and polar compounds. In the present work is the chemical study of these asphaltenes fractions by mass spectrometry of high resolution mass and accuracy, making use of the resonance cyclotron Ion Fourier Transform (FT-ICR MS) associated with the source of atmospheric pressure ionization - ESI (electrospray ionization), infrared, fluorescence and 1H NMR. The infrared analysis, 1H NMR and Fluorescence made it possible to observe differences among samples, where NS fraction had higher amounts of heteroatoms present and a higher percentage of aromatic hydrogens and NI fraction is nonpolar in the presence of increasing amounts of alkyl and naphthenic hydrocarbons. The results of FT-ICR MS corroborated with the other results, showing that the NS fractions showed high proportion of heteroatomics species and higher DBE values compared NI fractions exhibited predominantly hydrocarbon compounds and derisory amounts of heteroatoms and also insignificant quantities compounds of DBE values different from zero. / Os estudos das frações pesadas do petróleo são de grande importância para a indústria petrolífera, recebendo atenção especial nas últimas décadas devido ao interesse em conhecê-las visando a obtenção de compostos com maior valor agregado oriundos desta. Por outro lado, estes estudos também objetivam soluções para os problemas causados por essas frações durante todas as etapas de processamento do petróleo. Os asfaltenos em NMP produzem duas frações, uma solúvel e outra insolúvel em NMP. Foi sugerido que a fração NI apresente baixo teor de compostos aromáticos, abrindo um novo debate sobre a composição dos asfaltenos que são largamente discutidos na literatura como compostos aromáticos e polares. No presente trabalho realizou-se o estudo químico destas frações de asfaltenos por espectrometria de massas de altíssima resolução e exatidão, fazendo uso da Ressonância Ciclotrônica de Íons com Transformada de Fourier, (FT-ICR MS) associada com a fonte de ionização a pressão atmosférica – ESI (ionização por electrospray), infravermelho, fluorescência e RMN de 1H. As análises de infravermelho, RMN de 1H e fluorescência, possibilitaram observar as diferenças existentes entre as amostras, onde a fração NS apresentou maiores quantidades de heteroátomos presentes e maior porcentagem de hidrogênios aromáticos e a fração NI se mostrou apolar com a presença de maiores quantidades de hidrocarbonetos alquílicos e naftênicos. Os resultados de FT-ICR MS corroboraram com os demais resultados, evidenciando que, as frações NS apresentaram elevada proporção de espécies heteroatômicas e maiores valores de DBE quando comparadas as frações NI que exibiram predominância de compostos hidrocarbonetos e quantidades irrisórias de heteroátomos e também quantidades insignificantes de compostos com valores de DBE diferentes de zero.

Il existe un lien étroit entre la structure tridimensionnelle et la fonction cellulaire de l’ARN. Il est donc essentiel d’effectuer des études structurales de molécules d’ARN telles que les riborégulateurs afin de mieux caractériser leurs mécanismes d’action. Une technique de choix, permettant d’obtenir de l’information structurale sur les molécules d’ARN est la spectroscopie RMN. Cette technique est toutefois limitée par deux difficultés majeures. Premièrement, la préparation d’une quantité d’ARN nécessaire à ce type d’étude est un processus long et ardu. Afin de résoudre ce problème, notre laboratoire a développé une technique rapide de purification des ARN par affinité, utilisant une étiquette ARiBo. La deuxième difficulté provient du grand recouvrement des signaux présents sur les spectres RMN de molécules d’ARN. Ce recouvrement est proportionnel à la taille de la molécule étudiée, rendant la détermination de structures d’ARN de plus de 15 kDa extrêmement complexe. La solution émergeante à ce problème est le marquage isotopique spécifique des ARN. Cependant, les protocoles élaborées jusqu’à maintenant sont très coûteux, requièrent plusieurs semaines de manipulation en laboratoire et procurent de faibles rendements. Ce mémoire présente une nouvelle stratégie de marquage isotopique spécifique d’ARN fonctionnels basée sur la purification par affinité ARiBo. Cette approche comprend la séparation et la purification de nucléotides marqués, une ligation enzymatique sur support solide, ainsi que la purification d’ARN par affinité sans restriction de séquence. La nouvelle stratégie développée permet un marquage isotopique rapide et efficace d’ARN fonctionnels et devrait faciliter la détermination de structures d’ARN de grandes tailles par spectroscopie RMN. / The tridimensional structure of a given RNA molecule is closely linked to its cellular function. For this reason, it is crucial to study the structure of RNA molecules, such as riboswitches, to characterize their mechanism of action. To do so, NMR spectroscopy is often used to gather structural data on RNA molecules in solution. However, this approach is limited by two main difficulties. First, the production of preparative quantities of natively folded and purified RNA molecules is a long and tedious process. To facilitate this step, our laboratory has developed an RNA-affinity purification method using an ARiBo tag. The second limiting step comes from the extensive signal overlap detected on NMR spectra of large RNA molecules. This overlap is proportional to the length of the RNA, which often prevents high-resolution structure determination of RNAs larger than 15 kDa. To solve this problem, specific isotopic labeling of RNAs can now be achieved. However, existing labeling protocols are expensive, require several weeks of laboratory manipulations and usually provide relatively low yields. This thesis provides an alternative strategy to achieve specific isotopic labeling of RNA molecules, based on the ARiBo tag affinity purification technique. The protocol includes the separation and the purification of isotopically labeled nucleotides, an enzymatic ligation step performed on a solid support and the affinity purification of the RNA of interest, without any sequence restriction. This new strategy is a fast and efficient way to label functional RNAs isotopically and should facilitate NMR structure determination of large RNAs.

Il existe un lien étroit entre la structure tridimensionnelle et la fonction cellulaire de l’ARN. Il est donc essentiel d’effectuer des études structurales de molécules d’ARN telles que les riborégulateurs afin de mieux caractériser leurs mécanismes d’action. Une technique de choix, permettant d’obtenir de l’information structurale sur les molécules d’ARN est la spectroscopie RMN. Cette technique est toutefois limitée par deux difficultés majeures. Premièrement, la préparation d’une quantité d’ARN nécessaire à ce type d’étude est un processus long et ardu. Afin de résoudre ce problème, notre laboratoire a développé une technique rapide de purification des ARN par affinité, utilisant une étiquette ARiBo. La deuxième difficulté provient du grand recouvrement des signaux présents sur les spectres RMN de molécules d’ARN. Ce recouvrement est proportionnel à la taille de la molécule étudiée, rendant la détermination de structures d’ARN de plus de 15 kDa extrêmement complexe. La solution émergeante à ce problème est le marquage isotopique spécifique des ARN. Cependant, les protocoles élaborées jusqu’à maintenant sont très coûteux, requièrent plusieurs semaines de manipulation en laboratoire et procurent de faibles rendements. Ce mémoire présente une nouvelle stratégie de marquage isotopique spécifique d’ARN fonctionnels basée sur la purification par affinité ARiBo. Cette approche comprend la séparation et la purification de nucléotides marqués, une ligation enzymatique sur support solide, ainsi que la purification d’ARN par affinité sans restriction de séquence. La nouvelle stratégie développée permet un marquage isotopique rapide et efficace d’ARN fonctionnels et devrait faciliter la détermination de structures d’ARN de grandes tailles par spectroscopie RMN. / The tridimensional structure of a given RNA molecule is closely linked to its cellular function. For this reason, it is crucial to study the structure of RNA molecules, such as riboswitches, to characterize their mechanism of action. To do so, NMR spectroscopy is often used to gather structural data on RNA molecules in solution. However, this approach is limited by two main difficulties. First, the production of preparative quantities of natively folded and purified RNA molecules is a long and tedious process. To facilitate this step, our laboratory has developed an RNA-affinity purification method using an ARiBo tag. The second limiting step comes from the extensive signal overlap detected on NMR spectra of large RNA molecules. This overlap is proportional to the length of the RNA, which often prevents high-resolution structure determination of RNAs larger than 15 kDa. To solve this problem, specific isotopic labeling of RNAs can now be achieved. However, existing labeling protocols are expensive, require several weeks of laboratory manipulations and usually provide relatively low yields. This thesis provides an alternative strategy to achieve specific isotopic labeling of RNA molecules, based on the ARiBo tag affinity purification technique. The protocol includes the separation and the purification of isotopically labeled nucleotides, an enzymatic ligation step performed on a solid support and the affinity purification of the RNA of interest, without any sequence restriction. This new strategy is a fast and efficient way to label functional RNAs isotopically and should facilitate NMR structure determination of large RNAs.

Made available in DSpace on 2014-06-12T15:02:41Z (GMT). No. of bitstreams: 1 license.txt: 1748 bytes, checksum: 8a4605be74aa9ea9d79846c1fba20a33 (MD5) Previous issue date: 2008 / Conselho Nacional de Desenvolvimento Científico e Tecnológico / A mineração é um dos fatores de degradação dos ambientes costeiros do Brasil, dificultando o estabelecimento e a sobrevivência das plantas e da comunidade microbiana do solo. Na mina de Mataraca, estado da Paraíba, a retirada da vegetação e a intensa movimentação do solo têm causado modificações no sistema, comprometendo o processo de regeneração natural. Este trabalho teve como objetivos principais contribuir para ampliar o conhecimento sobre a diversidade de fungos micorrízicos arbusculares (FMA) em áreas de dunas, gerar informações sobre o impacto da mineração e da revegetação na comunidade desses organismos e avaliar os efeitos da inoculação com FMA no desenvolvimento e na sobrevivência de mudas utilizadas na revegetação da área. Foram estudadas quatro áreas de dunas revegetadas há 16, 12, 8 e 4 anos, uma área de duna natural e uma sem cobertura vegetal a ser revegetada. Três espécies utilizadas na revegetação foram selecionadas: Guazuma ulmifolia Lam., Tabebuia roseo-alba (Ridl.) Sandw. e Tocoyena selloana Schum., sendo avaliadas as contribuições da inoculação com FMA e da adubação com esterco bovino no crescimento das plantas, em casa de vegetação e em campo. A retirada e estoque da camada superficial do solo para recapeamento das dunas exploradas é importante para o estabelecimento da vegetação, porém afeta a comunidade de FMA, diminuindo a quantidade e infectividade dos propágulos no solo. O plantio de mudas contribuiu para o restabelecimento de propágulos micorrízicos nas dunas revegetadas. Cerca de 90% das 24 espécies vegetais avaliadas apresentaram-se naturalmente colonizadas, sendo identificadas 29 espécies de FMA na rizosfera destas plantas. As três espécies vegetais testadas formaram associação com os FMA e os efeitos da simbiose variaram com a planta hospedeira, com os fungos utilizados, com as proporções de esterco adicionadas aos substratos e com as condições de casa de vegetação e de campo. De modo geral, a adição de 10% de esterco bovino favoreceu a micorrização e o crescimento das plantas

No description available.

O propósito deste trabalho foi o desenvolvimento de um procedimento simulador de processo reproduzindo a etapa de destilação extrativa de uma unidade de extração de butadieno a partir de uma corrente de hidrocarbonetos na faixa de quatro átomos de carbono, através da adição do solvente n-metil-2- pirrolidona (NMP). Os resultados obtidos foram comparados e validados com dados de processo obtidos por uma unidade industrial de extração de butadieno. O aprofundamento nos conceitos do processo de separação através de uma ferramenta em simulador de processo capaz de predizer condições de operação permitiu avaliações de aumento de capacidade. A capacidade dos elementos internos dos equipamentos envolvidos na separação pode ser avaliada e a identificação do ponto inicial de engargalamento da unidade foi possível. O procedimento proposto também permite reduzir incertezas para identificação de novos pontos de engargalamento a partir de uma nova configuração dos elementos internos identificados como ineficientes com a elevação de carga processada. / The purpose of this study was the development of a model using a commercial process simulator software in order to reproduce the extractive distillation step of a butadiene extraction unit from a hydrocarbon stream by the addition of the solvent n- methyl-2-pyrrolidone (NMP). The results obtained from the simulations were compared with process data from an operational butadiene extraction unit. The knowledge of the separation process due the model should predict operating conditions allowing revamps on the actual asset. The internals capacity for the equipment involved in the separation could be evaluated and units bottlenecks points should be identified.