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  • 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.
171

Methane biofiltration in the absence and presence of ethanol vapors under steady state and transient state conditions / Biofiltration du méthane en absence ou en présence d’éthanol en régime permanent ou en régime transitoire

Ferdowsi, Milad January 2017 (has links)
Les émissions de méthane (CH[indice inférieur 4]), gaz à effet de serre provoquant le réchauffement climatique doivent être contrôlées. Les biofiltres peuvent être utilisés pour atteindre cet objectif. Les émissions de CH[indice inférieur 4] issues des industries agroalimentaires ou du traitement des eaux peuvent être accompagnées de vapeurs d’alcool. La présence simultanée de CH[indice inférieur 4], polluant à limitation par transfert de masse et d’alcool, polluant à limitation cinétique dans un mélange gazeux peut induire des limitations dans le biofiltre. L’objectif principal de cette recherche est l’évaluation des limitations dans un biofiltre traitant le CH[indice inférieur 4] en présence ou en absence de vapeur d’alcool en régime permanent ou transitoire. Dans un premier temps, une revue de littérature s’est penchée sur les limitations basées sur le transfert de masse et la cinétique lors de l’enlèvement de polluants organiques dans un biofiltre. Par la suite, l’élimination du CH[indice inférieur 4] a été effectuée dans un biofiltre afin d’évaluer l’influence de la concentration à l’entrée du biofiltre sur la performance du biofiltre. Une capacité d’élimination maximale de 45 g [indice supérieur -3] h[indice supérieur -1] a été obtenue pour une charge à l’entrée de 87 g [indice supérieur -3] h[indice supérieur -1] du biofiltre. Le biofiltre a toléré des charges par à-coups de CH[indice inférieur 4] de même que des privations de CH[indice inférieur 4] et de nutriments. Par conséquent, les comportements en régimes permanent et transitoire d’élimination du CH[indice inférieur 4] en présence de vapeurs d’éthanol ont été étudiés dans un biofiltre ayant un lit filtrant inorganique sous des temps de résidence en fût vide (EBRT) de 6, 3 et 1.5 minutes. L’ajout d’éthanol sur 3 cycles a été effectué en fonction des 3 EBRTs. Un EBRT de 6 min correspondant à des charges à l’entrée de CH4 et d’éthanol de 4.5 et de 132 g [indice supérieur -3] h[indice supérieur -1] a induit des limitations mineures en ce qui a trait à l’enlèvement du CH[indice inférieur 4] et de l’éthanol. En régime transitoire, la période de récupération après les 3 cycles a nécessité 10 à 25 jours. Ce délai est relié à la présence d’éthanol dans le lixiviat. Dans un dernier temps, deux biofiltres ayant un garnissage de pierres et un garnissage mixte ont été comparés pour l’enlèvement du CH[indice inférieur 4] et de l’éthanol présents dans un mélange gazeux en régime permanent. La section inférieure du biofiltre a permis l’élimination totale de l’éthanol. De plus, lors de l’élimination totale de l’éthanol dans la section inférieure du biofiltre, la production de dioxyde de carbone (CO[indice inférieur 2]) dépasse 16 g[indice supérieur -3] h[indice supérieur -1], pour des charges à l’entrée de CH[indice inférieur 4] et d’éthanol de 11 et 13 g m[indice supérieur -3] h[indice supérieur -1] respectivement. Par ailleurs, une concentration en éthanol dans le lixiviat excédant 2500 géthanol m[indice supérieur -3] lixiviat a été obtenue. Les biofiltres ont démontré une flexibilité pour des charges par à-coups d’éthanol suivies de périodes de carence. Le principal inconvénient du biofiltre à lit de pierres par rapport au biofiltre mixte est une perte de charge élevée dans la section inférieure du biofiltre. Une période de carence est un excellent moyen de contrer la perte de charge. / Abstract : Since methane (CH[subscript 4]) is a greenhouse gas with hazardous effects for global warming, every effort should be made to reduced methane emissions. Biofilters are potential candidates for CH[subscript 4] removal. In food and beverage industries as well as ethanol refineries, the feed of the biofilter might be a mixture of CH[subscript 4] emissions from wastewater treatment unit and ethanol emissions from other units. The presence of CH[subscript 4] as a mass transfer limited and ethanol vapor as a kinetic limited pollutant in a mixture can produce several limitations in a biofilter. The main objective of this research is to evaluate the limitations of CH[subscript 4] biofiltration or in the presence of ethanol vapors under steady and transient state conditions. First, a literature review was provided on mass transfer and kinetic limited organic pollutants removal in biofilters and the related limitations. Subsequently, the CH[subscript 4] elimination was assessed in a biofilter in order to evaluate the effect of CH[subscript 4] inlet concentration in the range of 1000 to 13000 ppmv and a gas flow rate of 3 L min[supercript -1] on the biofilter performance. A maximum CH[subscript 4] elimination capacity (ECmax) of 45 g m[superscript -3] h[superscript -1] was obtained for a CH[subscript 4] inlet load (IL) of 87 g m[superscript -3] h[superscript -1]. The biofilter tolerated CH[subscript 4] shock loads as well as different types of CH[subscript 4] and nutrient starvations. Subsequently, the steady state and dynamic behaviors of CH[subscript 4] elimination in the presence of ethanol vapor was studied in an inorganic bed biofilter with empty bed residence times (EBRTs) of 6, 3 and 1.5 min. Ethanol addition was performed in 3 cycles based on the EBRTs. An EBRT of 6 min with corresponding CH[subscript 4] and ethanol inlet loads of 132 and 4.5 gpollutant m[superscript -3] h[superscript -1] respectively, caused the least limitations for the simultaneous removal of CH[subscript 4] and ethanol in the biofilter. According to dynamic behavior of the biofilter, the recovery time after the three cycles took from 10 to 25 days. The delayed biofilter recovery was linked to the presence of ethanol in the liquid effluent. Finally, a stone-based bed and a hybrid packing biofilter were compared for CH[subscript 4] and ethanol removal in a mixture under steady and transient state conditions. Ethanol was completely removed in the bottom sections of both biofilters. A large carbon dioxide (CO[subscript 2]) production rate exceeding 18 g m[superscript -3] h[superscript -1] occurred in the bottom sections for CH[subscript 4] and ethanol inlet loads of 11 and 13 g m[superscript -3] h[superscript -1] respectively. In addition, an ethanol concentration in the leachate exceeding 2500 gethanol m[superscript -3] leachate was obtained for both biofilters. The biofilters were flexible to an ethanol shock load followed by a starvation period. The main drawback of the stone based bed biofilter compared to the hybrid packing biofilter was an excess pressure drop in the bottom section. Starvation was found an effective strategy for reducing the pressure drop.
172

EPIADDICT - Synthèses de nouveaux inhibiteurs des histones désacétylases et leur intérêt dans un modèle préclinique d’addiction à l’alcool. / EPIADDICT - Synthesis of the new interest histone deacetylase inhibitors in a preclinical model of addiction to alcohol.

Leteve, Mathieu 12 December 2016 (has links)
Le déséquilibre HAT/HDAC aurait une influence sur le développement de certains cancers ainsi que dans l’addiction à l’alcool ou à la cocaïne. En inhibant les histones désacétylases, le taux d'acétylation de la chromatine augmente ce qui permet l’accès aux facteurs de transcription et l'expression des gènes. Aujourd'hui, il existe de nombreux inhibiteurs d'HDAC de structures diverses, mais ils ne sont pas spécifiques et présentent des effets secondaires importants. Les inhibiteurs d'HDAC comme le butyrate de sodium ou le MS-275 ont montré une modification de la dépendance à l'alcool chez le rat. MS-275 inhibe principalement la classe I de HDAC et conformément à ces observations nous nous intéressons aux inhibiteurs les plus sélectifs de la classe I tels que le Largazole thiol et le RedFK228. Notre but est de synthétiser de nouveaux cyclodepsipeptides analogues afin d'obtenir un inhibiteur sélectif de la classe I. Les HDAC de la classe I sont Zn-dépendants, ces analogues auront un groupement sulfonylhydrazide ayant une bonne affinité pour l’ion Zn2+ (ZBG). Il sera relié au cyclodepsipeptide par un bras espaceur dont la longueur sera adaptée (n = 2, 3). Une autre pharmacomodulation concerne l'incorporation d’hétérocycles différents (oxazole, thiazole et pyridine). Les inhibitions de ces composés ont pu être testées sur HDAC1, HDAC3 et HDAC6. Un composé a une spécificité pour HDAC3 et un autre a une spécificité pour HDAC1. Les tests sur des rats "binger" permettent de penser que HDAC1 est impliqué dans ce model de consommation et non HDAC3. / The imbalance HAT/HDAC would influence the development of cancers and alcohol or cocaine addiction. HDAC inhibition allows increase of both acetylation rate and gene expression. Today, there are many structurally diverse potent, but non-specific HDAC inhibitors displaying important side-effects. HDAC inhibitors such as sodium butyrate or MS-275 have been shown to alter the alcohol dependence in the rat. MS-275 inhibits mainly class I of HDAC and in line with these observations we are interested in more selective class I inhibitors such as Largazole thiol and RedFK228. Our purpose is to synthesize new cyclodepsipeptides analogues in order to obtain selective class I inhibitor. HDAC class I is a Zn-dependent enzyme and our target molecules have sulfonylhydrazide function as efficient Zinc binding group (ZBG). Additional pharmacomodulations concern the incorporation of different heterocycles (oxazole, thiazole, pyridine) and varying linker lengths (n = 2, 3). Inhibitions of these compounds have been tested on HDAC1, HDAC3 and HDAC6. A compound has specificity for HDAC3 and another has specificity for HDAC1. Tests on rats "binger" suggest that HDAC1 is involved in this model of consumption and not HDAC3.
173

Synthèse de nanotubes de carbonne dopés à l'azote et leur application catalytique / Synthesis of nitrogen doped carbon nanotubes and their application in catalysis

Benyounes, Anas 24 March 2016 (has links)
L'objectif de ce travail est la synthèse et l'étude des propriétés acido-basiques de nanotubes de carbone (CNT) dopés à l’azote pour les utiliser comme catalyseurs ou supports de catalyseurs. Pour ce faire, trois types de nanotubes de carbone dopés à l'azote ont été synthétisés, caractérisés et testés dans la conversion de l'alcool isopropylique. Les nanotubes de carbone dopés diffèrent par le taux d’azote et la présence ou non d'une section non dopée dans leur structure. Pour les matériaux à faible teneur en azote, la réaction conduit à la formation d'acétone indiquant la présence de sites basiques. À plus forte teneur en azote, les catalyseurs dopés conduisent à la formation d'acétone et de propène, mettant en évidence la présence de sites basiques et acides. La caractérisation par XPS nous a permis de proposer que les sites basiques sont constitués de groupes de surface pyridiniques et les sites acides sont des groupements sulfoniques formés au cours de la purification de ces matériaux avec de l'acide sulfurique. Des catalyseurs au ruthénium et au palladium supportés (2%) sur des nanotubes de carbone non dopés et dopés à l'azote (N-CNT), ont été préparés et évalués dans la réaction de décomposition de l'alcool isopropylique comme réaction test. La présence de fonctionnalités azotées (azote pyridinique, pyrrolique et quaternaire) sur le support dopé à l'azote induit une plus grande dispersion du métal. En ce qui concerne les catalyseurs supportés, ceux de palladium étaient plus actifs et plus sélectifs que ceux au ruthénium. De plus, les catalyseurs au Pd sont sélectifs en acétone, tandis que les catalyseurs au Ru conduisent à la déshydratation et la déshydrogénation. Le dopage des nanotubes de carbone par l’azote conduit aussi à l'apparition de propriétés d'oxydo-réduction. Enfin, nous avons montré que des nanotubes de carbone, constitués de deux sections différentes : une partie non dopée hydrophobe reliée à un segment hydrophile, sont amphiphiles. Nous les avons utilisés comme supports tensioactif de catalyseur au palladium. Ces nouveaux catalyseurs à base de Pd supporté ont été testés dans la réaction d'oxydation de plusieurs alcools en utilisant l'oxygène moléculaire en phase liquide. L'oxydation du 2- heptanol produit sélectivement la cétone correspondante, alors que l'oxydation de l'alcool benzylique est très sélective vis-à-vis de l'aldéhyde. Par ailleurs, l'oxydation de l'éthanol produit de l'acide acétique de manière sélective. / The objective of this work is the synthesis and the investigation of the acid and basicproperties of nitrogen doped carbon nanotubes (CNTs) able to be used as catalysts or catalystsupports. For this, three types of purified nitrogen doped CNTs were synthesized,characterized and tested for isopropyl alcohol conversion under nitrogen or air atmosphere,and compared to undoped CNTs. The N-doped CNTs differ from their nitrogen content andfrom the presence or not of undoped section in their structure. The reaction lead to theformation of acetone as the sole product on catalysts presenting no nitrogen or low nitrogencontent (< 2.8% w/w), pointing to the presence of basic sites. At higher nitrogen content, Ndopedcatalysts lead to the formation of acetone and propene, highlighting the presence ofboth basic and acids sites on such material. XPS characterization allow us to propose that thebasic sites consist in pyridinic surface groups and the acidic sites in sulfonic surface groupsformed during the purification of these material with sulfuric acid. Ruthenium and palladiumsupported catalysts (2% w/w) were prepared on nitrogen-doped and non-doped carbonnanotubes (N-CNT), and evaluated for the reaction of decomposition of isopropyl alcohol asprobe reaction. The presence of nitrogen functionalities (pyridinic, pyrrolic and quaternarynitrogen) on the nitrogen doped support induces a higher metal dispersion: 1.8 nm (Pd/NCNT)< 4.9 nm (Pd/CNT), and 2.4 nm (Ru/N-CNT) < 3.0 nm (Ru/CNT). As far as thesupported catalysts are concerned, the palladium ones were more active and more selectivethan the ruthenium ones. The Pd catalysts were selective towards acetone, whereas Rucatalysts lead to dehydration and dehydrogenation products. The nitrogen doping induces theappearance of redox properties, which appear when oxygen is present in the reaction mixture.Finally, we have shown that unique amphiphilic magnetic hybrid carbon nanotubes thatcontain on the same nanotube two different sections: a hydrophobic undoped part connectedto a hydrophilic N-doped segment are synthesized and used as tensioactive supports forpalladium catalysts. These new Pd-supported catalysts have been used in the alcoholoxidation reaction using molecular oxygen in the liquid phase. The oxidation of 2-heptanolproduces selectively the ketone, the oxidation of benzyl alcohol is very selective towards thealdehyde, and ethanol oxidation produces selectively acetic acid.
174

Diversity of dopaminergic responses to drugs : a novel organizing principle of concurrent excitation and inhibition / Diversité de réponses dopaminergiques aux drogues : nouveau principe d'organisation simultané d'excitation et d'inhibition

Valverde, Sébastien 22 September 2015 (has links)
Les neurones dopaminergiques (DA) de l'aire tegmentale ventrale (VTA) sont au cœur du système de la récompense. Ils sont impliqués dans la transmission de messages liés au contrôle motivationnel et à l'apprentissage par renforcement, permettant de mettre en place des comportements adaptés à l'environnement, mais ont aussi un rôle important dans la mise en place des addictions. Les neurones DA de la VTA projettent majoritairement vers le Noyau Accumbens (NAc) et vers le Cortex Préfrontal (PFC). Ces neurones sont la cible des drogues d'abus qui ont toutes en commun une capacité à augmenter les niveaux de dopamine dans les structures cibles. En effet, les drogues agissent au niveau des neurones DA, ce qui provoque un détournement du système de récompense et mène à l'addiction. La nicotine module le système DAergique à travers ses actions sur les récepteurs nicotiniques à l'acétylcholine (nAChRs), qui sont fortement exprimés dans la VTA. Ainsi la nicotine provoque l'augmentation de la concentration de DA dans les zones de projection, ce qui sous-tendrait le développement de comportements maladaptés liés à une prise de drogue excessive. Néanmoins cette augmentation apparente du relargage de DA dissimule la complexité de la réponse du système DAergique à la nicotine. En effet, les neurones DA forment une population hétérogène qui ne répond pas uniformément ni aux évènements ni aux drogues. Ainsi mon travail s'est focalisé sur la caractérisation de la réponse hétérogène des neurones DA de la VTA à la nicotine. Contrairement à ce qui est communément accepté dans la littérature, la nicotine n'induit pas une augmentation généralisée de l'activité des neurones DA. Ainsi, j'ai pu analyser une sous-population DAergique qui est inhibée par la nicotine. Ces réponses à la nicotine simultanées et opposées sont anatomiquement dépendante, la population inhibée étant localisée de manière plus médiale dans la VTA que la population activée. Nous montrons que cette inhibition requiert l'activation de récepteurs DA inhibiteurs, et pourrait donc être médiée par un relargage de DA intra-VTA. Malgré le fait que nous observons aussi une ségrégation anatomique des réponses DAergiques à des évènements aversifs, ces réponses ne sont pas corrélées à celles induites par la nicotine et sont organisées de manière dorso-ventrale plutôt que médio-latérale, ce qui suggère que le message DAergique transmis en réponse à la nicotine n'est pas le même que celui transmis par l'aversion. De plus, nous avons trouvé que les réponses excitatrices et inhibitrices sont aussi induites pas d'autres drogues d'abus comme l'alcool et les benzodiazépines. Cela suggère que ces réponses peuvent être étendues à d'autres stimuli, mais aussi qu'il existe un principe d'organisation de la VTA qui est anatomiquement défini, par lequel la VTA latérale interagit avec la VTA médiale à travers un effet de réseau local. / Midbrain dopamine (DA) neurons of the ventral tegmental area (VTA) are at the center of the brain's reward system. They are involved in many different brain processes such as motivation, associative learning and reinforcement, and are critically involved in the pathophysiology of addiction. VTA DA neurons mostly project to the Nucleus Accumbens (NAc) and the Prefrontal Cortex (PFC) where they send signals related to motivational control. The common feature of drugs of abuse relates to their ability to increase DA levels in these regions. Indeed, drugs target VTA DA neurons, derailing the system from its natural reward-processing functions, which is thought to be the underlying neurophysiological mechanism leading to addiction. Nicotine is known to modulate the DAergic system through its actions on nicotinic acetylcholine receptors (nAChRs), which are highly expressed in the VTA. This results in an increase of DA concentrations in the areas of projection, which leads to the maladaptive behavior of nicotine addiction. However this apparent increase of DA release conceals the complexity of the system's response to nicotine. Indeed, DA neurons consist of a very heterogenous population, and don't respond uniformly to events or to addictive drugs. Thus my work has focused on the characterization of VTA DA neuron's heterogenous responses to nicotine. In contrast to the commonly acknowledged excitatory effect of nicotine on DA neurons, I've analyzed a subpopulation of DA neurons which are inhibited by nicotine. These concurrent but opposite responses to nicotine occur in an anatomically-dependent manner, with the inhibited population being localized more medially within the VTA compared to the activated population. We show that this inhibition requires the activation of inhibitory dopamine receptors, and could thus be mediated by an intra-VTA DA release. Although we also observe anatomically segregated excitatory and inhibitory responses to painful stimuli, these responses do not correlate to the ones induced by nicotine and are organized in a dorso-ventral fashion rather than a medio-lateral one, suggesting that the DAergic message conveyed by nicotine does not match the one conveyed by aversion. Moreover, we found that concurrent excitatory and inhibitory responses are also induced by other drugs of abuse such as ethanol and benzodiazepines. This suggests that these responses can be extended to other stimuli, but also that there exists an anatomically defined organizing principle of the VTA, in which the lateral VTA interacts with the medial VTA via a local network effect.
175

Attitudes et croyances de soignants hospitaliers envers des sujets âgés en difficulté avec l'alcool / Attitudes and beliefs of hospital caregivers to the elderly struggling with alcohol

Menecier, Pascal 11 March 2015 (has links)
Aborder puis accompagner dans les soins des sujets âgés en difficulté avec l'adolescent complexe pour tout soignant : infirmier ou médecin. le maintien d'une prévalence élevée du mésusage d'alcool chez les aînés, associée au vieillissement en cours de la population rendent cette question de plus en plus fréquenté à l'höpital et en établissement d'hébergement pour personnes âgées.le mésusage d'alcool est peu abordé chez les sujets âgés, peut-être moins car il est rare ou difficile à repérer, mais surtout par dénégation des troubles et contre-attitudes soignantes envers ces ainés. afin d'éviter l'âgisme et le rejet des ainés en difficultés avec l'alcool, les attitudes soignantes peuvent être prises en considération. pour cela, une étude d'observation descriptive sera menée en trois chapitres :- etude exploratoire auprès de sujets âgés en difficultés avec l'alcool : décrire les attitudes des soignants.- enquête auprès d'environ 750 soignants (625 infirmiers et 130 médecins de 8 hôpitaux à propos de leurs ressentis, attitudes et habitudes de soins avec des sujets âgés en difficulté avec l'alcool.- etude complémentaire par des entretiens directs d'un échantillon représentatif de soignants.sur ces bases, une réflexion théorique sera conduite autour de la vieillesse, du mésusage d'alcool et des représentations ou croyances des soignants, dans la perspective d'identifier des marqueurs ou facteurs d'attitudes positives et envisager des propositions de recours en prévention de contre-attitudes. / Introduction: Old age and alcohol misuse are only rarely considered together. While the prevalence of alcohol use disorder is located around 10% in the over 65 age bracket and while such situations are encountered daily by hospital or nursing-home caregivers, these elderly people suffering from alcohol misuse are often overlooked. Is it possible to consider this apparent neglect as a translation of negative counter-attitudes on the caregivers’ part?Methods: Two cross-sectional surveys, by means of questionnaires then by research interviews, were conducted among 582 nurses and 116 physicians working in 8 health facilities around Macon. The main objective was to approach the feelings, beliefs and attitudes of caregivers with older individuals who misuse alcohol. These variables were observed according to several socio-professional criteria and to the care provider’s level of knowledge in alcohology. The interviews were recorded and the dialogue was processed by Alceste® software.Results: The 315 completed questionnaires (response rate: 45%) of whom 81% were nurses and 19% physicians and of this number 84% were women. More than nine out of ten agents report meeting elderly alcohol misusers and this number is estimated at 12% of those cared for. The feelings then declared by the care-givers were shared out over 75% to listening or availability, 39% to aid or demonstration of skill, 32% to malaise, weakness or avoidance and 7% to aggression, repression or moralizing. Among the reasons which could oppose the development of appropriate care, only appear lack of training or lack of time. Correlations were objectified between positive attitudes and high level of knowledge, having had a life experience close to a familiar person misusing alcohol or to be himself an alcohol consumer. The 45 research interviews were conducted with 16 physicians and 29 nurses, of whom 69% were women. Discourses analysis has highlighted some specific extracts out of them: a less threatening perception of alcoholized elderly individual, the use of humor appearing specifically when alcohol is mentioned and questioning lack of time or training. The interviews allowed the highlighting of negative feelings and emotions and also emphasized the important role and the favorable impact of familiar experiences with sufferers of alcohol misuse in the life of the care provider.Discussion: Despite the limitations of non-validated questionnaires and the lack of focus groups, these two complementary studies confirm the significant frequency with which caregivers come into care situations with elderly individuals misusing alcohol. This point calls into question the ignorance which surrounds these situations which helps us to better understand their negligence and which may explain the small percentage of skilled addictological help given to the elderly person after early screening. The frequent allegation of lack of time or knowledge (and training) seems to be contradicted during the interviews by levels of knowledge that appear to be good. These claims can be caregivers’ defensive rationalizations concerning situations experienced as difficult. The question of denial may be considered in the same way: often referred to without being wary of its repercussion. Computerized speech analysis has led to crosschecking, studied in the light of several theories about narcissistic identification, dissimilarity / similarity, empathy or attachment.Conclusion: Caregivers’ attitudes about the elderly misusing alcohol appear to be variable, multifaceted, complex, according to the modes of observation, being neither good nor bad. Beyond the phenomenology of attitude, there is the consideration of internal elements of the caregivers’ thinking and those cared for which undergird care providers’ behavior. This approach seeks to promote a psychodynamic regard on the elderly who misuse alcohol trough the care-givers approach.
176

Les espèces actives durant la dégradation photocatalytique : application aux pesticides / Active species in the photocatalytic degradation : application to pesticides

Hazime, Roumayssaa 20 December 2012 (has links)
Ce travail de thèse a porté sur l'élimination d'un pesticide, l'imazalil, en phase aqueuse par trois procédés de dégradation (UV/TiO2, UV/TiO2/K2S2O8 et UV/K2S2O8) en mettant en oeuvre les outils analytiques nécessaires pour identifier les photoproduits de dégradation, suivre leur cinétique de formation et la minéralisation. L'ajout de K2S2O8 est bénéfique pour la dégradation et la minéralisation car il produit des radicaux sulfates qui sont des espèces oxydantes puissantes. Par ailleurs, le rôle des espèces radicalaires a été mis en évidence dans les trois systèmes de dégradation par des inhibiteurs de radicaux tels que les alcools (inhibiteurs des radicaux OH•). Dans une première partie, la dégradation de l'imazalil a été réalisée dans le système UV/TiO2 et les principaux photoproduits ont été identifiés par LC/MS/MS, leurs cinétiques ont été tracées. La minéralisation a été suivie et un mécanisme de dégradation a été proposé. La dégradation se déroule selon deux voies, par l'attaque des radicaux OH• ou par les trous. Dans une deuxième partie, la méthodologie de plans d'expériences a été établie dans le système UV/TiO2/K2S2O8 afin i) d'identifier les paramètres les plus influents et leurs interactions et ii) de déterminer les conditions expérimentales les plus favorables à la dégradation. Enfin, la dégradation de l'imazalil a été comparée dans les trois systèmes de dégradation en utilisant différentes concentrations de persulfate et différents pH. Il est apparu que la dégradation dans UV/TiO2, est plus efficace en milieu basique alors le pH acide est plus favorable à la dégradation de l'imazalil dans le système UV/TiO2/K2S2O8. Par contre, le pH ne joue pas un rôle important dans le système UV/K2S2O8 / The aim of this thesis was the degradation of the pesticide imazalil in water in three different systems of degradation (UV/TiO2, UV/TiO2/K2S2O8 and UV/K2S2O8). Analytical techniques were used to identify photoproducts, to follow their kinetics and mineralization. The addition of K2S2O8 is beneficial for the degradation and mineralization because it produces sulfate radicals that are powerful oxidizing species. In addition, the role of radical species has been highlighted in the three systems of degradation by using scavengers of these radicals such as alcohols (hydroxyl radical scavenger). In the first part, the degradation of imazalil was performed in the system UV/TiO2 and the main photoproducts were identified by LC/MS/MS also their kinetics were plotted. Furthermore, mineralization was followed and degradation mechanism was proposed. The degradation of imazalil could happen in two ways, by the attack of OH• radicals or by holes. In the second part, the methodology of experimental design was established in the system UV/TiO2/K2S2O8 to identify the most influential parameters also their interactions and to determine the experimental conditions that are most favorable to the degradation. Finally, the degradation of imazalil was compared in the three degradation systems using different concentrations of persulfate and different pH. It appears that the degradation in UV/TiO2 is more efficient in alkaline medium while the acidic pH is more favorable to the degradation of imazalil in the system UV/TiO2/K2S2O8. On the other hand, the pH does not play an important role in the system UV/K2S2O8
177

SEPPA - Sistema Especialista para Planta de Produção de Alcool / ESPPA - expert system plant for the production of alcohol

Bassetto, Nayara Zago 21 August 2006 (has links)
Orientador: Silvio Roberto Andrietta / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Quimica / Made available in DSpace on 2018-08-07T23:09:28Z (GMT). No. of bitstreams: 1 Bassetto_NayaraZago_M.pdf: 1198826 bytes, checksum: cc10dd78f55da0ba496ff27d88b3e57b (MD5) Previous issue date: 2006 / Resumo: Neste trabalho foi desenvolvido o sistema especialista SEPPA para auxiliar no projeto de construção ou reforma de uma planta industrial para produção de álcool anidro e hidratado fazendo o dimensionamento dos equipamentos, especificando o consumo de energia, o consumo de água e a produção de vapor. Um sistema Especialista é um software que é projetado e desenvolvido para atender a uma aplicação determinada do conhecimento humano. É capaz de emitir uma decisão, apoiado em conhecimento justificado, a partir de uma base de informações, tal qual um especialista de determinada área do conhecimento humano. Uma vez que é gasto um grande tempo para realização dos cálculos de dimensionamento de equipamentos e que pessoas são suscetíveis a erros por diversos fatores, este trabalho será de grande auxílio a todos os profissionais que trabalham dimensionando equipamentos para produção de álcool diminuindo o tempo de cálculo e detalhamentos, garantindo a certeza e precisão em todas as respostas, preservando e reproduzindo o conhecimento do especialista da área em questão. Utilizou para desenvolvimento das telas de interface com o usuário a linguagem de programação Delphi 5.0 e para armazenamento de dados o sistema de banco de dados Interbase 6.0. O Delphi é uma linguagem de programação orientada a objetos, e nos permite trabalhar com a herança em telas proporcionando agilidade no desenvolvimento destas e na implementação de códigos em opções comuns a todos os formulários. O Interbase é um eficiente e seguro banco de dados Cliente/Servidor relacional. A base de conhecimento do sistema foi adquirida através da experiência acumulada de um Engenheiro Químico, este foi construído para processos contínuos e possui algoritmos contendo cálculos de balanço de massa, balanço de energia e equações cinéticas. Através dos testes realizados o software mostrou ser seguro e apto a projetar uma planta industrial, seus resultados foram coerentes com os dados obtidos através dos cálculos e especificações realizadas por meio de um projeto manual utilizando os mesmos parâmetros de entrada / Abstract: In this work it was developed a Expert System an help in the design to built-up or restaur of building or reform industrial plant for the production of anidro and hydrated alcohol defining the size of the equipments, specifying the energy and water consumption and the vapor production. An Expert System is a software projected and developed to attend a determined application and limited of the humans knowledge. It¿s able to emit a decision, supported at justified knowledge, from the base of information, exactly a specialist of a determined area of the human knowledge. The Expert System has its mechanism supported at the heuristic processes. The reasoning process is made the realization of the importance of the facts and comparing it with information contained in the knowledge accumulated about this facts and hypothesis. This reasoning is always based in the previous accumulated knowledge. A specialist with this process is not able to achieve a right decision if the facts that dispose to apply your previous knowledge are not sufficient, and can arrive at a wrong conclusion in function of many reasons. Since is spent a big time to perform the calculations for the dimensionation of equipments and that people are always susceptible at mistakes for many factors, this work will be of a significant help to all the professionals that working dimension at the equipments to the alcohol production diminishing the time of calculations and details, guaranteeing the right answer and the precision so, preserving and reproducing the specialist knowledge of the area in question. It was utilized for the development the Interface and the language of programation Delphi 5.0 and to the storage of data was used the database Interbase 6.0. Delphi is a language of programation oriented to objects, and it permits to work with the inheritance at hardware¿s providing agility in the development of this and the implementation of codes in common options at all the formularies. Interbase is an efficient and safe database Client/ Server. The base of knowledge of system was acquired through the experience accumulated of chemistry engineers in the design of continuous process and has algorithms containing of mass and energy balances as well as thus kinetic equation. Through the tests carried out the software showed be safe and apt to project an industrial plant, its results were coherent with the data obtained through calculus and specifications realized by means of a manual project using the same entrance parameter / Mestrado / Desenvolvimento de Processos Biotecnologicos / Mestre em Engenharia Química
178

Capacitação tecnologica na agroindustria canavieira : o caso da COPER&UCAR

Ruiz Olalde, Alicia 18 December 1992 (has links)
Orientador : Lea M. Velho / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Geociencias / Made available in DSpace on 2018-07-17T11:07:36Z (GMT). No. of bitstreams: 1 RuizOlalde_Alicia_M.pdf: 10940415 bytes, checksum: 9bd478e41a37ab6a3922b2e3387a8b6b (MD5) Previous issue date: 1992 / Resumo: Este trabalho analisa a experiência em pesquisa e desenvolvimento da Cooperativa de Produtores de Cana, Açúcar e Álcool do' Estado de São Paulo (COPERSUCAR). São apontandos os fatores que levaram à internalização da pesquisa por parte desta cooperativa no contexto das relações de produção predominantes na agroindústria canavieira. Por outro lado, são analisados os diversos programas de pesquisa desenvolvidos pelo Centro de Tecnologia da COPERSUCAR desde 1969, na área de melhoramento vegetal, no processamento industrial e na área de máquinas agrícolas. Por último, é avaliada a contribuição desta experiência para a capacitação tecnol6gica no setor sucro-alcooleiro no país / Abstract: This text analyses the R&D experience of the COPERSUCAR (Alcohol and Sugar Cane São Paulo State Producers Cooperative). The factors that have induced "in house" research are discussed, on the context of the prevalescent production relations of the sugar cane agro-industry. The distinct research programs developed by the CTC (COPERSUCAR Technology Center) since 1969 are also analysed, with special emphasis on the vegetable improvement, industrial process and agricultural machinery areas. As a last point, it is analysed the CTC contribution to the technological capacitation of the brazilian sugar-alcohol productive sector / Mestrado / Politica Cientifica e Tecnologica / Mestre em Geociências
179

Modernização, relações de trabalho e poder : um estudo das transformações recentes na agroindustria canavieira do Nordeste

Novaes, Jose Roberto Pereira 25 June 1993 (has links)
Orientador: Jose Graziano da Silva / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Economia / Made available in DSpace on 2018-07-18T10:57:23Z (GMT). No. of bitstreams: 1 Novaes_JoseRobertoPereira_D.pdf: 9683091 bytes, checksum: 420920a83001e23ee842d46f21a8184d (MD5) Previous issue date: 1993 / Resumo: Não informado / Abstract: Not informed. / Doutorado / Doutor em Economia
180

Demanda e conservação de oleo diesel na fase agricola do PROALCOOL

Ferreira, André Luis, 1960- 13 January 1992 (has links)
Orientador: Sergio Valdir Bajay / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de engenharia Mecanica / Made available in DSpace on 2018-07-18T17:34:48Z (GMT). No. of bitstreams: 1 Ferreira_AndreLuis_M.pdf: 5693204 bytes, checksum: 1b18cdd779842d9c73fe63dd1752db5e (MD5) Previous issue date: 1992 / Resumo: Não informado / Abstract: Not informed. / Mestrado / Mestre em Planejamento de Sistemas Energéticos

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