• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 15
  • 5
  • 5
  • 4
  • 1
  • 1
  • Tagged with
  • 38
  • 38
  • 10
  • 7
  • 6
  • 6
  • 6
  • 6
  • 5
  • 5
  • 5
  • 5
  • 5
  • 5
  • 5
  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
21

APPLICATION OF PROCESS ANALYTICAL TECHNOLOGY TO PHARMACEUTICAL PROCESSES

HAUSMAN-MANNING, DEBRA SUE 23 May 2005 (has links)
No description available.
22

Process Fingerprinting of Microneedle Manufacturing Using Conventional and Ultrasonic Micro-injection Moulding

Gulcur, Mert January 2019 (has links)
This research work investigates the development and application of process fingerprinting for conventional micro-injection moulding and ultrasonic micro injection moulding manufacturing of microneedle arrays for drug delivery. The process fingerprinting method covers in-depth analysis, interrogation and selection of certain process data features and correlation of these features with product fingerprints which are defined by the geometrical outcomes of the microneedle arrays in micro scale. The method was developed using the data collected using extensive sensor technologies attached to the conventional and ultrasonic micromoulding machines. Moreover, a machine vision based microneedle product evaluation apparatus is presented. Micromachining capabilities of different processes is also assessed and presented where state-of-the-art laser machining was used for microneedle tool manufacturing in the work. By using process fingerprinting procedures, conventional and ultrasonic micromoulding processes has been characterised thoroughly and aspects of the process that is affecting the part quality was also addressed for microneedle manufacturing. It was found that polymer structure is of paramount importance in obtaining sufficient microneedle replication. An amorphous polymer have been found to be more suitable for conventional moulding whereas semi-crystalline materials performed better in ultrasonic micromoulding. In-line captured micromoulding process data for conventional and ultrasonic moulding provided detailed insight of machine dynamics and understanding. Linear correlations between process fingerprints and micro replication efficiency of the microneedles have been presented for both micromoulding technologies. The in-line process monitoring and product quality evaluation procedures presented in this work for micro-injection moulding techniques will pave ways for zero-defect micromanufacturing of miniature products towards Industry 4.0.
23

Metodologia para o diagnóstico em tempo real de para-raios em sistemas de distribuição e transmissão de energia elétrica / Methodology for Real Time Diagnostic of Surge Arresters in Electric Energy Distribution and Transmission Systems

Alves, Marcos Eduardo Guerra 08 November 2013 (has links)
Dada a importância dos para-raios para a proteção dos diversos equipamentos e instalações nos sistemas de distribuição e transmissão de energia elétrica contra danos provocados por sobretensões transitórias, quer sejam originadas por descargas atmosféricas, quer por estabelecimento e interrupção de cargas reativas (sobretensões de manobra), é apresentada uma nova metodologia de diagnóstico de seu estado. São apresentadas também as formas construtivas dos para-raios com tecnologias de carboneto de silício (SiC) e óxido de zinco (ZnO), as quais são associadas a modelos elétricos de representação completos e simplificados, de forma a facilitar a análise dos métodos de diagnóstico. Os métodos atualmente empregados para o diagnóstico dos para-raios, tanto fora de serviço quanto durante a operação, bem como suas potencialidades e pontos falhos são explanados, para os equipamentos de SiC e de ZnO. O novo método de diagnóstico proposto nesse trabalho é introduzido a seguir, baseado na monitoração da capacitância equivalente e resistência equivalente do para-raio, juntamente com simulações dos diversos tipos de defeitos passíveis de ocorrência em equipamentos de SiC e ZnO, verificando-se os parâmetros de medição afetados por cada um deles, de forma a estabelecer a efetividade do novo método de monitoração para a detecção dos defeitos. Também é apresentado um método para viabilização da monitoração em tempo real de capacitância e de resistência equivalentes, através da técnica de soma vetorial das correntes de fuga, atualmente já empregada para monitoração de buchas capacitivas de transformadores e outros equipamentos. Por fim, são apresentados os resultados esperados com o novo método de monitoração e as sugestões de novas etapas para trabalhos futuros. / Given the importance of surge arresters for the protection of several devices and installations in electric energy distribution and transmission systems from damages caused by transitory overvoltages, either originated from atmospheric discharges or by closing or opening of reactive loads (switching overvoltages), a new methodology for diagnosing their condition is presented. The constructive forms of surge arresters with silicon carbide (SiC) and zinc oxide (ZnO) technologies are presented, as well as their associated electric representation models, complete and simplified, so as to facilitate the analysis of diagnostic methods. Surge arrester diagnostic methods are presented, both off-line and on-line, together with their potentialities and weak points, for SiC and ZnO arresters. The new diagnostic method proposed in this work is introduced next, based on monitoring of the arrester equivalent capacitance and equivalent resistance, followed by simulations of the several possible defect types in SiC and ZnO devices. The measured parameters affected by each defect type are checked in order to establish the effectiveness of the new monitoring method for the detection of arrester problems. A method for making the monitoring of equivalent capacitance and resistance is also presented, by using the vector sum of leakage currents technique, largely used for monitoring of capacitive bushings in power transformers and other equipment. Finally, the results expected with the new monitoring method and suggestions for future work are presented.
24

Etude en temps réel du processus dextraction de la Tagitinine C en fonction des caractéristiques physico-chimiques du CO2 supercritique à laide de fibres optiques couplant un spectrophotomètre IRTF à un extracteur à fluide supercritique Real time monitoring of the extraction process of Tagitinin C according to the physicochemical properties of supercritical CO2 by means of optical fibers coupling a FT-IR spectrometer and a supercritical fluid extractor

Ziemons, Eric 24 November 2006 (has links)
Lextraction par fluide supercritique fait partie des nouvelles techniques de préparation déchantillons solides qui ont émergé au cours de ces dernières années. Elle constitue une alternative intéressante aux techniques classiques dextraction liquide-solide car le pouvoir solvant du fluide supercritique est ajustable, non seulement par la température, mais aussi par la pression. Lextraction par le CO2 supercritique de la tagitinine C, lactone sesquiterpénique photo sensible à lactivité anti-inflammatoire, anti-malarique et anticancéreuse à partir des parties aériennes de Tithonia diversifolia constituait une application intéressante de ce procédé et a été sélectionnée comme molécule cible dans le cadre de ce travail. Son optimisation a impliqué des dosages répétés de lanalyte dont la vibration délongation de la fonction diénone absorbe intensément à des fréquences particulières dans le domaine de linfrarouge. Aussi, avons-nous tout dabord développé et validé, dans la première partie de ce travail, une technique IRTF danalyse en différé sélective, rapide, non destructrice et sensible fondée sur ses propriétés. Les différents paramètres (température, pression, quantité de CO2, granulométrie de léchantillon) influençant le rendement dextraction de lanalyte ont pu être étudiés à cette occasion. Dans les conditions optimales, nous avons montré que lextraction par le CO2 supercritique extrayait rapidement et avec une meilleure sélectivité la tagitinine C tout en conservant un taux de récupération comparable aux techniques classiques dextraction. Parallèlement à ces travaux et compte tenu de la photo-dégradation de la tagitinine C en tagitinine F, la formation de complexes dinclusion avec la β, 2,6-di-O-méthyle-β et la -cyclodextrine a été investiguée. Différentes techniques ont été employées pour caractériser les complexes formés au niveau de la stchiométrie, de la constante de formation et de la structure. Aucun effet photo-protecteur significatif na été démontré avec la β et la -cyclodextrine. En revanche, nous avons mis en évidence une diminution de la vitesse de la photo-dégradation en présence de la 2,6-di-O-méthyle-β-cyclodextrine. Malheureusement, celle-ci reste trop limitée pour envisager lutilisation de cette cyclodextrine pour éviter la dégradation de la tagitinine C lors de son exposition à la lumière directe. Dans la dernière partie de notre travail, nous nous sommes plus particulièrement focalisés sur linterfaçage EFSC/IRTF qui constituait un indéniable défi. Le développement de linterfaçage a été réalisé à laide de fibres optiques en chalcogène darsenic entre un extracteur à fluide supercritique et un spectrophotomètre IR et a ainsi permis deffectuer le dosage en ligne de la tagitinine C dans le CO2 supercritique après passage de celui-ci au travers dune cartouche dextraction contenant la matrice végétale. Par ailleurs, le développement de cet outil répond parfaitement aux nouvelles approches (Process and Analytical Technology) préconisées par la FDA. Le processus dextraction de lanalyte a pu dès lors être étudié de manière approfondie et en temps réel en fonction des caractéristiques physico-chimiques du fluide supercritique et de la durée de lextraction. Lutilisation de la vibration délongation CH comme marqueur a permis de mettre en évidence lobtention dextraits de composition variable qui pourront être utilisés directement dans des études defficacité thérapeutique. Enfin, la méthode dextraction et de dosage en ligne de la tagitinine C a fait lobjet dune validation poussée selon la nouvelle approche faisant appel aux profils dexactitude dans un intervalle de dosage allant 500 à 2500 µg. Sur la base des différents profils dexactitude obtenus, le modèle de régression linéaire a été choisi pour décrire la relation concentration-réponse. En effet, ce modèle présentait des valeurs de biais relatif inférieures à 2%, des valeurs de coefficient de variation ne dépassant pas 4% et des limites de tolérance comprises dans les limites dacceptation de ±15% sur toute la gamme de concentration. De plus, le modèle de régression linéaire était en parfaite adéquation avec la méthode des ajouts dosés. In the last two decades, supercritical fluid extraction processing with carbon dioxide has emerged as an alternative to the conventional solvent extractions of solid matrices and especially for the extraction of natural products for foods and medicines. Indeed, carbon dioxide is an inert, inexpensive, widely available, odourless, environment-friendly solvent and its solvent strength can be tuned by changing the pressure and temperature conditions. In the first part of our work, supercritical fluid extraction of tagitinin C, a known sesquiterpene lactone which shows significant antiplasmodial and antiproliferative activity, was investigated using an off-line FTIR method for the determination of this compound in the aerial parts of Tithonia diversifolia. Different parameters as temperature, pressure, solvent mass and sample granulometry governing the supercritical fluid extraction process were optimised. Finally, we demonstrated that the optimised supercritical fluid extraction gave extraction yields comparable to those of the classical methods of extraction but with an improvement of the selectivity and a reduction of the extraction time. At the same time, the formation of inclusion complexes of tagitinin C with β-, 2,6-di-O-methyl-β and -cyclodextrin was investigated according to its photochemical conversion into tagitinin F. Several techniques were used to characterize the tagitininC/CyD complexes in order to understand and to interpret the data obtained from the photochemical study. This letter mainly showed that the photodegradation rate of tagitinin C was slowed in presence of 2,6-di-O-methyl-β-cyclodextrin while no significant effect was observed in presence of β- and -cyclodextrin. The second part of our work was devoted to the SFE/FTIR interfacing which was a great challenge. This interface was constructed from a stainless steel cross cell equipped with chalcogenide-glass infrared fibers. This hyphenated system allowed to determine on-line tagitinin C in supercritical CO2 after this one flowed through the extraction vessel containing the plant material. Consequently, the extraction process of the analyte was studied thoroughly and in real time according to the physicochemical characteristics of the supercritical fluid and to the extraction time. The use of the CH stretching vibration as tracer allowed to highlight the composition change of extracts which could be used directly in studies of therapeutic efficiency. In addition, the development of this tool answers perfectly the new approaches (Process and Analytical Technology) recommended by the FDA. Finally, the extraction and on-line determination method of tagitinin C was successfully validated using a new approach based on accuracy profiles as decision tool. On this basis, a linear regression model was chosen for the calibration curve. Regarding trueness, precision and accuracy, mean measured values were close to the theoretical concentrations (lower than 1.6%) and the RSD values were relatively low (less than 4% for the middle of the range). Moreover, the method was found to be accurate as the two-sided 95 % beta-expectation tolerance interval did not exceed the acceptance limits of 85 and 115 % on the concentration range from 500 to 2500 µg.
25

Metodologia para o diagnóstico em tempo real de para-raios em sistemas de distribuição e transmissão de energia elétrica / Methodology for Real Time Diagnostic of Surge Arresters in Electric Energy Distribution and Transmission Systems

Marcos Eduardo Guerra Alves 08 November 2013 (has links)
Dada a importância dos para-raios para a proteção dos diversos equipamentos e instalações nos sistemas de distribuição e transmissão de energia elétrica contra danos provocados por sobretensões transitórias, quer sejam originadas por descargas atmosféricas, quer por estabelecimento e interrupção de cargas reativas (sobretensões de manobra), é apresentada uma nova metodologia de diagnóstico de seu estado. São apresentadas também as formas construtivas dos para-raios com tecnologias de carboneto de silício (SiC) e óxido de zinco (ZnO), as quais são associadas a modelos elétricos de representação completos e simplificados, de forma a facilitar a análise dos métodos de diagnóstico. Os métodos atualmente empregados para o diagnóstico dos para-raios, tanto fora de serviço quanto durante a operação, bem como suas potencialidades e pontos falhos são explanados, para os equipamentos de SiC e de ZnO. O novo método de diagnóstico proposto nesse trabalho é introduzido a seguir, baseado na monitoração da capacitância equivalente e resistência equivalente do para-raio, juntamente com simulações dos diversos tipos de defeitos passíveis de ocorrência em equipamentos de SiC e ZnO, verificando-se os parâmetros de medição afetados por cada um deles, de forma a estabelecer a efetividade do novo método de monitoração para a detecção dos defeitos. Também é apresentado um método para viabilização da monitoração em tempo real de capacitância e de resistência equivalentes, através da técnica de soma vetorial das correntes de fuga, atualmente já empregada para monitoração de buchas capacitivas de transformadores e outros equipamentos. Por fim, são apresentados os resultados esperados com o novo método de monitoração e as sugestões de novas etapas para trabalhos futuros. / Given the importance of surge arresters for the protection of several devices and installations in electric energy distribution and transmission systems from damages caused by transitory overvoltages, either originated from atmospheric discharges or by closing or opening of reactive loads (switching overvoltages), a new methodology for diagnosing their condition is presented. The constructive forms of surge arresters with silicon carbide (SiC) and zinc oxide (ZnO) technologies are presented, as well as their associated electric representation models, complete and simplified, so as to facilitate the analysis of diagnostic methods. Surge arrester diagnostic methods are presented, both off-line and on-line, together with their potentialities and weak points, for SiC and ZnO arresters. The new diagnostic method proposed in this work is introduced next, based on monitoring of the arrester equivalent capacitance and equivalent resistance, followed by simulations of the several possible defect types in SiC and ZnO devices. The measured parameters affected by each defect type are checked in order to establish the effectiveness of the new monitoring method for the detection of arrester problems. A method for making the monitoring of equivalent capacitance and resistance is also presented, by using the vector sum of leakage currents technique, largely used for monitoring of capacitive bushings in power transformers and other equipment. Finally, the results expected with the new monitoring method and suggestions for future work are presented.
26

Monitoramento permanente de motores de indução trifasicos / On-line monitoring of three-phase induction motors

Lamim Filho, Paulo Cezar Monteiro 23 February 2007 (has links)
Orientador: Robson Pederiva / Tese (doutorado) - Universidade Estadual de Campinas. Faculdade de Engenharia Mecanica / Made available in DSpace on 2018-08-09T22:58:42Z (GMT). No. of bitstreams: 1 LamimFilho_PauloCezarMonteiro_D.pdf: 3058410 bytes, checksum: b3139213ab7f18f3ff80772b9e063ab3 (MD5) Previous issue date: 2007 / Resumo: Um programa de manutenção preditiva deve englobar várias técnicas de monitoramento a condição do motor elétrico. Dentre elas, pode-se citar como clássicas, a análise de corrente elétrica e análise de vibrações. Entretanto, existe um grande número de dificuldades associadas com estas técnicas e, conseqüentemente, com suas aplicações in loco no parque fabril. Isto ocorre devido ao largo espectro de possíveis defeitos, tais como: curto circuito entre espiras, desequilíbrio de fase e falhas de barras rotativas do rotor. Este trabalho propõe a implementação de um transdutor (bobina de fluxo) sensível às ondas eletromagnéticas dentro dos motores de indução trifásicos para a detecção, diagnóstico e monitoramento on-line. Foi obtida uma relação entre as principais falhas de origem elétrica (curto circuito entre espiras, desequilíbrio de fase e barras quebradas) com os sinais de fluxo magnético, sendo estabelecidas as freqüências características de falhas. No trabalho é proposto o uso da lógica fuzzy para o monitoramento online. A condição do motor é descrita através de variáveis lingüísticas. Uma base de regras foi construída para ser usada pelo método de inferência fuzzy. O motor de indução é diagnosticado pela composição do conjunto de regras do método de inferência. Os resultados experimentais comprovaram a eficiência do sensor proposto e da estratégia de detecção, diagnóstico e monitoramento on-line, podendo ser futuramente incluídos em Programas de Manutenção Preditiva / Abstract: A predictive maintenance program must include several techniques of monitoring of the electric motor¿s conditions. Among these techniques, probably the two most classic ones are related to electric current and vibration analysis. Unfortunately, in both cases inherent drawbacks make difficult their use in loco on industry plants. As there is a large range of possible fault sources and abnormal machine use conditions (such as inter-turn short circuits, unbalanced voltage supplies and broken rotor bars) the determination of the real machine problem is difficult. This work presents the implementation of a special sensor developed (flux coil sensor) inside three-phase induction motors used as experimental platforms. This sensor is sensitive to electromagnetic waves and they are used for detection, diagnosis, and on-line monitoring of electrical faults. It was established a relation between the main electrical faults (inter-turn short circuits, unbalanced voltage supplies and broken rotor bars) and the signals of magnetic flux, that were identified the characteristic frequencies of these faults. In this work, it is proposed the use of fuzzy logic for the on-line monitoring. The motor operational conditions are described by using fuzzy linguistic variables. A knowledge base, comprising fuzzy rules and databases, was built to support the fuzzy inference process. The conditions of the induction motors used during the test phase are diagnosed using a compositional rule and fuzzy inference procedures. The experimental results shown the efficiency of the flux coil sensor developed and the strategies for detection, diagnosis, and on-line monitoring tasks. The results were undoubtedly impressive and in a near future the system developed can be adapted and used in real predictive maintenance programs in industries / Doutorado / Mecanica dos Sólidos e Projeto Mecanico / Doutor em Engenharia Mecânica
27

Acquisition de données en conditions non-conventionnelles par l’utilisation de gouttes comme microréacteurs de polymérisation dans un réseau millifluidique / Data acquisition of acrylic acid polymerization performed at high concentration and temperature by using a droplet-based millifluidic device

Lorber, Nicolas 26 October 2011 (has links)
Le but de ce travail de thèse est le développement d'un outil miniaturisé basé sur la millifluidique en goutte qui permet de synthétiser et d'étudier en toute sécurité des réactions de polymérisation dans des conditions difficiles ou «extrêmes».À cette fin, le réacteur de polymérisation a été réduit à la taille d'une gouttelette de quelques microlitres. A cette échelle, le microréacteurs goutte a un rapport surface sur volume plus élevé que ceux qui sont couramment obtenus avec des réacteurs discontinus classiques (~ 1500 par rapport à 10). Cette surface importante permet le transfert de chaleur efficace entre le milieu intérieur de la gouttelette (où la réaction chimique a lieu) et le milieu externe, qui est chimiquement inerte. Ici, contrairement à une approche monophasique, les caractéristiques clés d'une goutte miniaturisés permettent : (1) les gouttelettes de haute viscosité interne peuvent circuler normalement sans boucher le canal et (2) la dispersion due à la convection et la diffusion est éliminé car les réactifs sont compartimentées dans les gouttelettes. Comme toutes les gouttelettes se déplacent à la même vitesse, elles ne coalescent pas et il n'y a pas de distribution du temps de résidence. Ceci est particulièrement important étant donné que la viscosité dans des réactions de polymérisation peut augmenter à des milliers de centipoises ou même plus dans le cas des processus de gel.L'utilisation de gouttes comme microréacteurs circulant dans un tube chauffé (1/8’’ dext et 1/16’’ dint) peut permettre d’observer rapidement et en toute sécurité des réactions de polymérisation à différentes conditions. Nous avons choisi d'utiliser des conditions expérimentales où le processus de polymérisation est rapide et exothermique et/ou la viscosité peut être un problème. L'acide acrylique à faible pH et à concentrations élevées est donc un bon candidat pour obtenir un tel comportement. La composition des gouttelettes dépendant uniquement des débits, il est facile d’étudier différentes conditions expérimentales, y compris celles qui ne pouvaient pas être observées dans des réacteurs discontinus conventionnels (i.e. les concentrations de monomère et températures élevées, 40% massique et 90°C).Par ailleurs, couplé avec des systèmes appropriés d'analyse, des données cinétiques de base peuvent être obtenus en ligne à travers la paroi du tube transparent. En utilisant la spectrométrie Raman et l'équivalence temps-espace qui est spécifique à l'utilisation de dispositifs micro-et millifluidique à base de gouttes, nous avons été capables de suivre la conversion du monomère en fonction du temps. Ainsi, nous avons obtenu une cinétique d'ordre 4/3 en fonction de la concentration initiale en monomère et une demi-dépendance avec la concentration initiale de l'amorceur. Nous avons également pu mesurer une énergie d'activation globale de la vitesse de polymérisation entre 68°C et 90°C.En conclusion, la millifluidique et goutte semble être une approche prometteuse pour le criblage haut débit, l’analyse, et l’obtention de données cinétique de base en synthèse de polymères. / The aim of this thesis work is the development of a miniaturized droplet-based millifluidic tool which allows to safely synthesize and investigate polymerization reactions in harsh or “extreme” conditions.For this purpose, the polymerization reactor was reduced to the size of a droplet of a few microliters. At this scale, the droplet microreactor has a surface to volume ratio higher than those commonly obtained with conventional batch reactors (~1500 compare to 10). This important surface allows efficient heat transfer between the internal medium of the droplet (where the chemical reaction takes place) and the external one, which is chemically inert. Here, in contrast to single-phase flows, other key characteristics to a miniaturized droplet-based approach consist in: (1) droplets can manage high internal viscosity issues without plugging the channel and (2) dispersion due to convection and diffusion is eliminated because the reactants are compartmentalized within droplets. Since all droplets move at the same speed, they do not coalesce and there is no residence time distribution. This is particularly important since viscosity in polymerization reactions can increase to thousand of centipoises or even higher in the case of gel processes.The use of droplets as batch microreactors flowing within a heated tube (1/8 in. o.d. and 1/16 in. i.d.) can allow investigating quickly and safely polymerization reactions at different conditions. We choose to use experimental conditions where fast and exothermic polymerization process occurs and/or viscosity can be an issue. Acrylic acid at low pH and high concentrations is hence a good candidate to obtain such behavior. Since droplet composition depends only on flow rates, it was easy to screen different experimental conditions, including those which could not be used in conventional batch reactors (i.e., high monomer concentrations and temperatures; 40% w/v and 90 °C).Moreover, coupled with appropriate and sensitive analytical systems, basic kinetic data can be obtained in line through the wall of the transparent tube. By using Raman spectrometry and the time-space equivalence which is specific to the use of droplet-based micro- and millifluidic devices, we were capable to monitor molar conversions and monomer concentrations as a function of time. Thus, we verified the 4/3 order kinetics in initial monomer concentration and a 1/2 dependence in initial initiator concentration. We also able measured the overall activation energy for the rate of polymerization between 68°C to 90°C.In conclusion, droplet-based millifluidics seems to be a promising high throughput screening approach for investigating kinetics and possibly tailoring polymer properties.
28

Espectroscopia Raman e quimiometria como ferramentas no monitoramento on-line do processo fermentativo da glicose pela Saccharomyces cerevisiae / Raman spectroscopy and chemometrics for on-line monitoring of glucose fermentation by Saccharomyces cerevisiae

Ávila, Thiago Carvalho de, 1985- 22 August 2018 (has links)
Orientador: Ronei Jesus Poppi / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Química / Made available in DSpace on 2018-08-22T08:18:21Z (GMT). No. of bitstreams: 1 Avila_ThiagoCarvalhode_M.pdf: 7831860 bytes, checksum: 010f2295e00f097a9ecfaf3f498a7069 (MD5) Previous issue date: 2013 / Resumo: Este trabalho visou o uso de Espectroscopia Raman e de Quimiometria para monitoramento e controle da fermentação de glicose por Saccharomyces cerevisiae. Na primeira etapa, foi utilizada calibração multivariada baseada no método dos Mínimos Quadrados Parciais (PLS) para quantificação de glicose, etanol, glicerol, ácido acético e células. Os modelos foram desenvolvidos baseados nos valores de concentração obtidos pelos métodos de referência, cromatografia líquida de alta eficiência ¿ HPLC e espectrofotometria UV/Vis. Tanto na etapa de calibração quanto na de validação, a otimização foi realizada com eliminação de amostras anômalas, baseada nos valores de leverage, resíduos e escores. Na segunda etapa, cartas de controle multivariadas foram usadas para identificação de falhas em bateladas durante o processo de fermentação. Foram construídos modelos MPCA (Análise de Componentes Principais Multimodo) a partir de bateladas NOC (Condições Normais de Operação). As cartas de controle multivariadas foram aplicadas em dois modos de desdobramento dos dados obtidos durante o monitoramento, um preservando a direção das bateladas e outro a direção do tempo. As falhas estudadas foram temperatura, mudança no substrato e contaminação do sistema. No modo de desdobramento por bateladas, a carta de controle Q foi eficiente para detecção das falhas estudas, fato comprovado pela classificação correta de três bateladas NOC como dentro de controle. No entanto, a carta de controle T2 não foi capaz de identificar as falhas estudadas corretamente como fora de controle. O modo de desdobramento pelo tempo também apresentou classificações corretas das falhas estudadas / Abstract: This work aims the use of Raman Spectroscopy and Chemometrics in the monitoring and control in the fermentation of the glucose by Saccharomyces cerevisiae. In the first step, it was applied the multivariate calibration based on Partial Least Squares (PLS) for the quantification of glucose, ethanol, glycerol, acetic acid and cells. The developed of calibration models was performed against the concentration values obtained by the reference methods, High Performance Liquid Chromatography and UV/Vis spectrophotometer. The optimization of the calibration and validation steps, the elimination of outliers was performed based on the values of leverage, residues and scores. In the second step, multivariate control charts were used for identification of batch-fault during the fermentation process. Multi-way Principal Component Analysis (MPCA) models were developed from batch NOC (Normal Operation Conditions). The multivariate control charts were based on two modes of unfolding the multi-way data, obtained during monitoring, one preserving the direction of the batch and another the direction of time. The fault studied were temperature, changes in the substrate and contamination of the system. In unfolding batch mode, the chart Q was effective for detection of the faults studied, proven by the correctly classification of 3 NOC batches as in control. However, the chart T2 failed to identify faults studied. The unfolding in time mode, also presented correct classifications of the faults studied / Mestrado / Quimica Analitica / Mestre em Química
29

Etude de l'adsorption spécifique des isomères de dioxine sur des matériaux microporeux pour la mesure en ligne à l'émission des sources fixes / Study of specific dioxin adsorption onto microporous materials for online measurement in stationary sources emission

Ben Abda, Maher 02 March 2016 (has links)
Les dioxines/furanes sont des polluants organiques persistants générés principalement par l’activité anthropique et spécifiquement par l’industrie lors des procédés de combustion mettant en jeux des matières organochlorées. Etant donné leur transport à large échelle dans l'environnement et leur impact sur la santé de l’homme, il est nécessaire de contrôler en temps réel, les traces de dioxines à l'émission des sources fixes. Un tel contrôle est plus particulièrement requis lors de l’incinération de déchets hétérogènes non préalablement triés. Deux types de matériaux microporeux ont été sélectionnés pour l'adsorption des dioxines au vu de leurs propriétés physico-chimiques. Il s’agit des zéolithes et les Metal-Organic Frameworks (MOF). Deux types de test d’adsorption ont été conduits, d’une part, en laboratoire en phase liquide avec la dioxine dans de l’isooctane comme solvant, et d’autre part, en phase gazeuse lors des campagnes de prélèvement sur un site d'incinération de déchets avec une matrice réelle très complexe. L'adsorption en phase liquide nous a permis de conclure sur l’efficacité des matériaux étudiés pour l’adsorption de trois congénères de dioxine de différentes tailles. Elle a ensuite été caractérisée par des techniques d'analyses spécifiques afin de remonter aux mécanismes d'adsorption. L’efficacité d’adsorption a été testée en phase gaz sur un site d'incinération de déchets ménagers avec les mêmes matériaux testés en phase liquide au laboratoire. Finalement, en se basant sur les résultats d'adsorption en phases liquide et gaz, deux pistes ont été proposées pour la conception d’un dispositif de mesure de dioxines en ligne commercialisable. / Dioxins and furans are persistent organic pollutants generated mainly by human activity and industry during combustion processes using organochlorine substances. Due to their long-range air transport and impact on human health, it is necessary to have on-line dioxin emission monitoring at stationary source. Such a control is tipically required for incineration of no pre-sorted heterogeneous wastes.Two types of microporous materials have been selected for dioxin adsorption due to their physicochemical properties: zeolites and Metal -Organic Frameworks (MOF). Two types of adsorption tests have been established. On the one hand, dioxin adsorption tests in liquid phase in laboratory with isooctane as solvent, and on the other hand, dioxin adsorption tests in dynamic gas phase during sampling campaigns on waste incineration site with a very complex matrix.Liquid phase adsorption allowed us to conclude on the effectiveness of materials studied for dioxin adsorption. Adsorption has been after characterized by specific analysis techniques to trace adsorption mechanisms. Adsorption efficiencies were tested in gas phase on a household waste incinerator with the same materials tested in liquid phase in laboratory. Finally, taking into account liquid and gas phase results, two solutions have been proposed for a future commercialized device for on-line dioxin monitoring.
30

Métrologie des pressions partielles de gaz (CO2 et CH4) à l'équilibre avec les eaux de formation des marnes de Bure (Meuse - Hte Marne, France) et Mont Terri (St Ursanne, Suisse) : interprétation des mécanismes de transfert de gaz après forage / Metrology of gas partial pressures (CO2 and CH4) at equilibrium with formation porewatersof Bure marls (Meuse Hte Marne, France) and Mt Terri (St Ursanne, Switzerland) : interpretation of the migration mechanisms of gases after drilling

Cailteau, Christelle 04 July 2008 (has links)
Pour mieux appréhender les mécanismes de transfert des gaz (CO2 et CH4) dissous dans l’eau porale des formations des marnes du site de Bure et des argiles à Opalinus (AOP) du Mt Terri dans leur état initial, un capteur infrarouge (IRTF) et un banc optique Raman innovant ont été développés et installés en laboratoire souterrain. Ces capteurs sont intégrés au dispositif de l’expérimentation « d’équilibration de gaz » développée par l’Andra (PAC) qui vise à suivre l’évolution d’une phase gazeuse initialement neutre au contact de la formation et de son eau porale grâce à un forage effectué et maintenu dans des conditions anaérobiques. Ces capteurs permettent un suivi quantitatif in situ et en ligne des gaz libérés par la formation à basse pression totale (<1,3 bar). Les modèles quantitatifs développés pour la mesure infrarouge ont une erreur relative moyenne de 1,66 % pour la pCO2 (mbar.m) et de 1,37 % pour la pCH4 (mbar.m). L’instrumentation IR d’un forage sur le site du Mt Terri et de deux forages sur le site de Bure (faciès C2b1 et C2d) a permis d’obtenir les courbes de transfert des deux gaz. Les courbes de transfert du CH4 ont été modélisées par un modèle de diffusion-advection qui ont permis l’évaluation de la concentration locale en CH4 dissous dans l’eau porale : elles sont comprises entre 3,06 et 14,23 mg.L-1 pour les AOP, et entre 0,36 et 1,28 mg.L-1 pour le faciès C2d et entre 0,56 et 1,55 mg.L-1 pour le faciès C2b1 des argilites de Bure. On montre que les équilibres eau/gaz/roche gouvernent la pCO2 après forage alors que la diffusion/advection explique son évolution sur le long terme. Une origine intraformationnelle des alcanes dissous est envisagée / An infrared sensor (IRTF) and an innovative Raman optical bench were implemented and developed in underground laboratories to improve our knowledge about migration mechanisms of dissolved gases (CO2 and CH4). This study is focussed on the characterisation of the initial state of the porewater of Callovo-Oxfordian marl (Bure) and Opalinus Clay (Mt Terri Middle Jurassic). These sensors are integrated into experimental devices of gas-equilibration test developed by Andra (PAC) to follow the gaseous phase behaviour in contact with the rock formation through a borehole drilled and maintained in anaerobic conditions, and initially filled with pure argon. These in situ sensors allow, on line quantitative analysis of gases released by the rock formation at low bulk pressure (<1.3 bar). Quantitative models were developed to transform peak intensities in partial pressures of gas. They give mean absolute relative errors about 1.66 % for pCO2 (mbar.m) and 1.37 % for pCH4 (mbar.m). Three years of IR monitoring of one borehole on the site of Mt Terri and two boreholes on the site of Bure (facies C2b1 and C2d) have been led. CH4 transfer curves were modelled by diffusion-advection. CH4 concentration in porewater from non-perturbed rock formation is estimated from all the experiments: concentrations between 3.06 and 14.23 mg.L-1 was obtained for Opalinus Clay, between 0.36 and 1.28 mg.L-1 for C2d facies and between 0.56 and 1.55 mg.L-1 for C2b1 facies in Callovo-Oxfordian marls of Bure. Gas/rock/water balance governs pCO2 after drilling, whereas diffusion/advection laws explain CO2 long-term profiles. An intra-formational origin of the organic gases can be proposed

Page generated in 0.1294 seconds