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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.
161

Relações humanas com a água : percepção ambiental, saberes tradicionais, simbolismos culturais e contribuições para a gestão e conservação da água

Dictoro, Vinicius Perez 08 April 2016 (has links)
Submitted by Bruna Rodrigues (bruna92rodrigues@yahoo.com.br) on 2016-10-06T12:59:48Z No. of bitstreams: 1 DissVPD.pdf: 4876346 bytes, checksum: 5063cb0041e85a46af9399007dd98dee (MD5) / Approved for entry into archive by Marina Freitas (marinapf@ufscar.br) on 2016-10-20T13:57:56Z (GMT) No. of bitstreams: 1 DissVPD.pdf: 4876346 bytes, checksum: 5063cb0041e85a46af9399007dd98dee (MD5) / Approved for entry into archive by Marina Freitas (marinapf@ufscar.br) on 2016-10-20T13:58:03Z (GMT) No. of bitstreams: 1 DissVPD.pdf: 4876346 bytes, checksum: 5063cb0041e85a46af9399007dd98dee (MD5) / Made available in DSpace on 2016-10-20T13:58:11Z (GMT). No. of bitstreams: 1 DissVPD.pdf: 4876346 bytes, checksum: 5063cb0041e85a46af9399007dd98dee (MD5) Previous issue date: 2016-04-08 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / For many centuries, mankind has considered fresh water as inextinguishable feature, without evaluating the environmental consequences related to quantity and quality. The current form of appropriation of water to meet the high demand of the various uses of water resources by the company has configured intense transformations in human relations with the water. In the old days, companies had other complementary visions to the direction of the water deities, bows and very natural available both for human existence and other species, as to the balance and maintenance of ecosystems. Therefore, human relations with the water permeate this relationship of utilitarian sense, only for economic purposes and survival, and configure other relationships as: religious, cultural, symbolic and emotional. In this way, the overall objective of the research was to identify and analyze different human relationships with water, seeking to understand the varied forms of recovery of water, and also to analyze the current model of water management through National Water Resources Policy instruments, for the purpose of providing subsidies that may assist in the consideration of human relationships with water in its management and conservation. This was followed by work based on qualitative research and case study was developed in two distinct audiences, residents of Pirapora-MG, situated on the banks of the São Francisco River, and members of river basin committees. The data were collected through interviews and questionnaires. Symbolic, cultural relations were identified, mystical and local knowledge, affective of individuals with the water. These aspects should be transmitted in new forms of awareness for the management and conservation of water. It is necessary to step up the way of acting on awareness, promote new programs and new actions with the purpose of expanding the vision centered on Man and on their anthropogenic activities, enabling a rescue of cultural symbolism of the water and the various relationships and appreciation that it has with society. / Durante muitos séculos, a humanidade considerou a água doce como recurso inextinguível, sem avaliar as consequências ambientais relacionadas à sua quantidade e qualidade. A atual forma de apropriação da água para atender a alta demanda dos diversos usos dos recursos hídricos pela sociedade tem configurado intensas transformações nas relações humanas com a água. Antigamente as sociedades possuíam outras visões complementares ao sentido da água, como divindades, reverências e bem natural disponível tanto para a existência humana e demais espécies, quanto para o equilíbrio e manutenção dos ecossistemas. Portanto, as relações humanas com a água perpassam essa relação de sentido utilitarista, voltada apenas para fins econômicos e de sobrevivência, e configuram outras relações como: simbólicas, religiosas, culturais e emocionais. Dessa forma, o objetivo geral da pesquisa foi identificar e analisar diferentes relações humanas com a água, buscando-se compreender as variadas formas de valorização da água, e também de analisar o atual modelo de gestão da água por meio dos instrumentos da Política Nacional de Recursos Hídricos, com a finalidade de prover subsídios que possam auxiliar na consideração das relações humanas com a água em sua gestão e conservação. Este trabalho seguiu-se com base na pesquisa qualitativa e o estudo de caso foi desenvolvido em dois públicos alvos distintos, moradores de Pirapora- MG, situados nas margens do rio São Francisco, e membros de Comitês de Bacias Hidrográficas. Os dados foram coletados por meio de entrevistas e questionários estruturados. Foram identificadas relações simbólicas, culturais, afetivas, místicas e saberes locais dos indivíduos com a água. Esses aspectos devem ser transmitidos em novas formas de sensibilização para a gestão e conservação da água. É preciso intensificar a forma de atuar na sensibilização, promover novos programas e novas ações com a finalidade de expandir a visão centralizada no Homem e em suas atividades antrópicas, possibilitando um resgate cultural do simbolismo da água e das diversas relações e valorização que ela possui com a sociedade.
162

A implementação da municipalização do ensino em quatro municipios da região de São João da Boa Vista, SP - (1997-2003)

Lucio, Roque 12 December 2005 (has links)
Orientador: Zacarias Pereira Borges / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Educação / Made available in DSpace on 2018-08-05T20:41:14Z (GMT). No. of bitstreams: 1 Lucio_Roque_M.pdf: 950689 bytes, checksum: 08c819ed7acbd4f88501f73bd78c5d93 (MD5) Previous issue date: 2005 / Resumo: Esta pesquisa enfoca a implementação da municipalização do ensino em quatro municípios da região de São João da Boa Vista (SP) de 1997 e 2003: Mococa, São José do Rio Pardo, São Sebastião da Grama e Tapiratiba. Procurou-se entender: Por que quatro municípios do estado de São Paulo tomaram diferentes caminhos na implementação de uma mesma política educacional? O trabalho teve como objetivos: analisar a implementação da municipalização do ensino nos quatro municípios tendo em vista a utilização dos recursos financeiros do FUNDEF; investigar se houve melhoria no processo ensino ¿ aprendizagem, tomando como ponto de partida a municipalização do ensino, identificar os fatores positivos e apontar insuficiências e equívocos, buscando o aperfeiçoamento ou reformulação desta política educacional e oferecer subsídios à ação de Dirigentes Municipais de Educação, para continuidade ou mudanças de rumo nesta política educacional. Tratou-se, portanto, de pesquisa qualitativa, utilizando-se como referencial teórico a Análise de Política e tendo como procedimentos a análise de documentos legais dos municípios estudados, do estado de São Paulo e do Brasil, bem como de dados estatísticos, entrevistas e questionários semi-estruturados. Apresentou-se, como pano de fundo, a política educacional brasileira, enfocando a condição do Município na Federação, a autonomia dos municípios, as políticas de descentralização do século XIX à Constituição Federal de 1988 e à sua emenda indutora da municipalização do ensino. Apresentaram-se os perfis dos municípios envolvidos: fundação, contexto atual, municipalização do ensino, análise dos recursos financeiros recebidos no período e a implementação da municipalização. Comparam-se, em seguida os processos de municipalização do ensino nos quatro municípios, desvelando-se suas diferenças e similitudes. Por fim, estabeleceu-se um contraponto com alguns estudos da temática e um balanço da consecução dos objetivos e apontam-se algumas conclusões, com a indicação de ações pertinentes ao processo de municipalização em andamento / Abstract: This search brings to a focus the settlement of municipal autonomic upbringing systems in four towns in the region of São João da Boa Vista from 1997 to 2003: Mococa, São José do Rio Pardo, São Sebastião da Grama and Tapiratiba.It was tried to understand why four towns in São Paulo upstate carried out in different ways the same upbringing policy. The purposes of this work have been: analysis of how municipal autonomic upbringing systems have been performed in four towns as to the usage of FUNDEF pecuniary resources; inquiry about municipal autonomic upbringing system to find out whether there was improvement in process of teaching and apprenticeship or not, as a result of the municipal autonomic upbringing system settlement, and at the same time to identify positive elements and to point out faults, shortages and mistakes in order to better or to plan out again such an upbringing policy and finally to offer subsidies for municipal upbringing active leaders to perform their work so that the adopted upbringing policies may go or be changed. This work intends to be a quality search as it uses the political inquiry as a theoretical remark and the examination of town hall legal documents as procedure ¿ just those from thes towns in São Paulo upstate and from other towns in Brazil which have been studied here; statistical data, interviews and half-structured questionaries. As a background, the brazilian national education policy appears bringing to a focus the condition of the municipal district in federacy, the self-government of municipal districts, the decentralizing policies in the nineteenth century up till the national constitution in 1988 and its amendment inducing to settlement of municipal autonomic upbringing system. The following profiles of the municipal districts that brought forth their own upbringing systems come to mind: foudation, today¿s context, settlement of municipal autonomic upbringing system, examination of pecuniary resources cashed in for that purpose and the accomplishment of municipal upbringing plan. Afterwards, the four types of municipal autonomic upbringing system (in the four municipal districts here mentioned) are compared with each other and differences and likenesses (similiarities) are revealed. Finally, a couterpoint is set up towards some studies about the theme as well as a ponderation about ends gained. Some illations are brought forward and actions pertaining to the municipal autonomic upbringing system newly settled are pointed out / Mestrado / Politicas de Educação e Sistemas Educativos / Mestre em Educação
163

O descoroamento da Princesa do Sertão : de "chão" a território, o "vazio" no processo de valorização do espaço

Freitas, Nacelice Barbosa 08 January 2014 (has links)
To study the process of territorial formation in the state of Bahia, we catagorised Feira de Santa in scaled sections, aiming to unveil euphemism and practices that create the powers supported by political and economic institutions on this geographical scale. The study focuses on the Sertão/territory as the locus of implementation of the territorial capital, a space which is understood as a dialectical relationship in its multiple scaled dimensions. The difference between litoral and sertão (coastal & dry land) explained under the Marxist orientation, falls within the social and territorial division of labour, where the social and political are subjected to the scrutiny of the capital in its multiple determinations. The reality is contradictory in its making and remaking the geography of the sertão (dry land) and signifies the concreteness of this movement. The starting point-is that Feira de Santana-is the scale of analysis, a place that serves as the foundation for the pursuit of know ledge about the territorial formation of the sertão. The construction/creation of the Bahian sertão establishes a challenge to consider the economic and political importance of the geographical location of Feira de Santana, as Princess and Portal of the Sertão. The research process has made it possible to understand the profound changes in its urban space and the historical context helping to establish the city as Princess of Sertão. The investigation led to the territorial analysis treated as the sertanejo- litorâneo relationship, which is the formation of the Brazilian nation. In conclusion, it is the Sertão that creates a Brazilian nationality, therefore this is a space that is instructed to carry a nomenclature full of stereotypes and multiple meanings. Feira de Santana is included in this place considered by many scholars as a space of no precise location, undefined, the fragile borders. There is a primitive accumulation and store of value in the territory. This condition causes a transformation into ground territory, where the idea of emptiness throughout space-time, is an essential context to the process of creating value for the capital. The Sertão, in the sertanejo area, assumes different meanings in constituting the streams of the capital. / Estudar o processo de formação territorial no estado da Bahia, tendo Feira de Santana como recorte escalar, visa desvelar circunlóquios e práticas que materializam os poderes sustentados por instituições políticas e econômicas sobre esta escala geográfica. O estudo enfoca o sertão/território como lócus da implantação da territorialização do capital, espaço que é compreendido enquanto relação dialética em suas múltiplas dimensões escalares. A diferença litoral versus sertão explicada sob o viés marxista se inscreve na divisão social e territorial do trabalho, onde o social e o político estão submetidos ao crivo do capital em suas múltiplas determinações. Se o real é contraditório no seu fazer e (re)fazer-se, a geografia do sertão é concretude desse movimento. O ponto de partida - Feira de Santana - é a escala de análise, lugar que serve de alicerce para a busca do conhecimento sobre a formação territorial do sertão. A construção/criação do sertão baiano institui um desafio para se pensar a importância econômica e política da localização geográfica de Feira de Santana, enquanto Princesa do Sertão e Portal do Sertão. O processo de investigação tornou possível perceber as profundas transformações no seu espaço urbano. Cada contexto histórico contribuindo para firmar a cidade como Princesa do Sertão. A investigação conduziu a análise territorial tratada como relação sertanejo-litorânea que é a formação da nação brasileira. Conclui-se que é no sertão que se produz uma nacionalidade brasileira porquanto esse não é somente um espaço que se incumbiu de carregar uma nomenclatura repleta de estereótipos e múltiplos significados. Feira de Santana se inclui nesse lugar considerado por muitos estudiosos como espaço de localização imprecisa, indefinida, de fronteiras fragilizadas. Território de acumulação primitiva e reserva de valor. Essa condição a conduz a ser chão transformado em território, onde a ideia de vazio foi ao longo do espaço-tempo, conteúdo essencial para o processo de valorização do capital. Sertão, sertanejo que assume diferentes significados para constituir-se vereda do capital.
164

Nouvelles formes de valorisation territoriale en agriculture : le cas de l’arboriculture de la moyenne vallée du Rhône / News forms of territorial valorization in agriculture : the case of the arboriculture in the middle Rhône valley

Praly, Cécile 30 June 2010 (has links)
L’arboriculture de la Moyenne Vallée du Rhône, concurrencée par les pays à faible coût de production, subit une importante crise structurelle. Dans ce contexte, nous interrogeons les liens existants entre l’arboriculture et ses territoires. Ils peuvent en effet constituer des ressources mobilisées par les acteurs locaux pour développer des formes de valorisation territoriale.Le modèle productif historique de l’arboriculture de la Moyenne Vallée du Rhône, celui de bassin de production-expédition, est aujourd’hui remis en question par deux tensions opposées. La première, dite « centrifuge », est exercée par les principaux expéditeurs qui élargissent leur aire d’approvisionnement au-delà de celle du bassin de production pour être capables d’offrir des volumes de fruits standardisés satisfaisant à la demande des grands distributeurs. A l’inverse, un ensemble de tensions « centripètes » produisent un effet de morcellement interne au bassin, résultant des initiatives d’identification territoriale des fruits portées par les producteurs. A l’intersection de ces tensions, les arboriculteurs développent des stratégies pour maintenir la viabilité économique de leurs exploitations. La tendance est d’ajouter aux circuits d’expédition existants de nouveaux débouchés qui valorisent plusieurs proximités entre production et consommation. Nous décrivons ainsi des « circuits de proximité » pluriels et multi-scalaires, où interviennent différents types de professionnels (grossistes, détaillants, IAA), de consommateurs (habitants ou plus éloignés) et de modes de commercialisation. S’articulant entre concurrence et complémentarité au bassin de production-expédition, ces circuits bénéficient de soutiens de la part des collectivités territoriales. La conclusion de la thèse propose une caractérisation des différents circuits de proximité ainsi qu’un cadre théorique pour penser la diversité des formes de valorisation territoriale en agriculture. / The fruit growing sector in the Middle Rhône Valley, competed by low-cost-production countries, faces a serious structural crisis. Then, we analyze the links between the arboriculture and its territories which can constitue resources mobilized as territorial valorization forms by local actors.The historic productive model of the arboriculture in the Middle Rhône Valley, the production-shipping basin, is now questioned by two rival forces. The first, called « centrifugal », is exercised by the main shippers who enlarge their supply area to be able to deliver large volumes of standardized fruits, relevant for the main retailers demand. In the opposite, some « centripetal » forces produce a fragmentation effect in the basin. These result from territorial identification initiatives for fruits, lead by the producers.Between these forces, farmers develop some strategies to maintain economic viability of their farms. They add to the existing shipping-circuits news outlets which valorize various proximities between production and consumption. We describe multi-scale « proximity circuits », including different types of the fruits supply chain actors, of consumers and marketing chanels. These circuits are shaped by competition and complementarity relationships with the basin of production-shipping. They benefit from the local communities supports.The conclusion of the research displays a characterization of the different proximity circuits and a theorical model to analyze the diversity of territorial valorization forms in agriculture.
165

Caractérisation d'un nouveau matériau et valorisation dans les barrières perméables réactives / Characterisation of a new material and its valorization in a permeable reactive barriers

Zakaria, Khaled 14 December 2012 (has links)
La valorisation des déchets industriels est de nos jour un défit international ayant des intérêts économiques et environnementaux. Dans ce cadre, l’entreprise Solvay travail sur la gestion de ses déchets et plus particulièrement ceux produits de la fabrication du carbonate de sodium « soude ». Ils sont actuellement stockés dans des bassins de décantation. Cependant, des contraintes règlementaires sont récemment apparues limitant ainsi la construction de nouveaux bassins. La valorisation de ces déchets est par conséquent impérative pour l’entreprise. Plusieurs voies de valorisation sont envisageables, notamment le recours à des nouveaux procédés qui permettraient d’en produire de nouveaux matériaux.En effet, un nouveau matériau issu des déchets industriels appelé « Gel d’Apatite » fait l’objet de ce travail de thèse. L’objectif est de caractériser le Gel d’Apatite et de proposer et d’étudier une voie permettant sa valorisation. Ce matériau est constitué principalement d’hydroxyapatite et de l’eau. Il se distingue par un comportement thixotropique et par sa capacité de rétention des métaux lourds. Cette dernière propriété a permis d’envisager sa valorisation dans la dépollution et la protection des nappes phréatiques. La voie étudiée dans ce travail de recherche est la valorisation du Gel d’Apatite dans les Barrières Perméables Réactives « BPR(s)»; technique passive de traitement des eaux souterraines in-situ.La finalité de ces travaux de recherche serait de dresser un cahier de charge du Gel d’Apatite et de définir un mélange conforme au mode de valorisation étudié / The valorization of industrial wastes is nowadays a worldwide challenge that offers several environmental and social interests. In some fields this valorization allows the preservation of natural resources and the releasing of spaces devoted to the wastes storage. Further, it allows developing of new innovative materials and low-cost products. Consequently industries industries have followed these guidelines. A collaborative investigation has been established with Solvay and Ecole Centrale de Lille in order to work on this topic.A new material: hydroxyapatite gel, is thus developed from non-toxic wastes in an industrial research laboratory. This material is composed by hydroxyapatite and water. It is characterized by its capacity to retain heavy metal by ion exchange. This particular characteristic led to consider its valorization in the water pollution control as the permeable reactive barrier (PRB) in particular. In deed, the permeable reactive barrier is a passive technique of in situ groundwater treatment.The results from this study were useful for a better planning of Permeable Reactive Barriers (PRB). The latter requires a high permeability to ensure groundwater flow and a high retention capacity for heavy metals
166

Etude physico-chimique, biochimique et stabilité d’un nouveau produit : jus de cladode du figuier de Barbarie marocain (Opuntia ficus-indica et Opuntia megacantha). / Physicochemical, biochemical and stability study of a new product : Moroccan prickly pear cladode juice (Opuntia ficus - indica and Opuntia megacantha)

Boutakiout, Amale 21 July 2015 (has links)
Les orientations de la politique agricole marocaine, notamment le Plan Maroc Vert, encouragent la valorisation des zones arides et le développement de cultures qui s’adaptent au réchauffement climatique. Le figuier de Barbarie est une plante qui s'adapte au climat aride et semi-aride mais il reste encore sous-exploité au Maroc. Les cladodes du figuier de Barbarie sont largement consommées au Mexique et elles contiennent des composants bioactifs qui ont des effets bénéfiques sur la santé. Le jus extrait à partir des cladodes des deux espèces Opuntia ficus-indica (inerme) et Opuntia megacantha (épineuse) a fait l’objet de ce travail. Les cladodes ont été récoltées dans la région de Marrakech (commune rurale Ouled Dlim) au Maroc durant trois saisons entre 2013 et 2014 (printemps, été et hiver) afin d’évaluer l’effet du temps de récolte sur la composition physico-chimique et biochimique ainsi que sur les propriétés antioxydantes. Le rendement en jus des cladodes varie en fonction des saisons et des espèces (20,83 – 63,39 %). Les analyses physico-chimiques et biochimiques ont montré que le jus de cladode est riche en polyphénols (455,65 ± 7,63 – 542,70 ± 1,35 µg EGA/ mL), en acide ascorbique (17,60 ± 1,87 – 22,88 ± 0,62 mg /100 mL) et en potassium (44,23 – 409,35 mg /100 mL), mais pauvre en sucre (0,66 ± 0,01 – 1,45 ± 0,03 g /100 mL). L’analyse HPLC sur les composés phénoliques a montré que le jus de cladode est riche en flavonols à savoir l’isoquercetine et l’hyperoside (645,90 µg/mL et 164,50 µg/mL respectivement). L’activité antioxydante du jus de cladode a été mesurée avec le test FRAP (1,74 ± 0,07 – 3,33 ± 0,02 µmol ET/mL) et l’activité antiradicalaire a été réalisée avec le test DPPH (1,78 ± 0,03 – 4,10 ± 0,02 µmol ET/mL) et le test ABTS (12,78 ± 1,69 – 23,10 ± 0,17 µmol ET/mL). La corrélation entre les analyses a montré qu'il y avait une relation significative (p<0,05) entre les méthodes d’analyses, les espèces et les saisons. Le jus de cladode extrait à partir de l’espèce épineuse (Opuntia megacantha) et la récolte effectuée au mois d’août nous ont donné les plus grandes valeurs en composants biochimiques et pour l’activité antioxydante. L’analyse quantitative du jus de cladode du mois de mars par HPLC-DAD à montré la présence d’une quantitié importante de flavonoïdes essentiellement l’isoquercetine et l’hyperoside. Les résultats de cette étude ont montré la richesse du jus en nutriments et son potentiel antioxydant. Le jus de cladode peut être conservé durant 42 jours à 4°C, après une pasteurisation à 95°C pendant 3 min dans un bain-marie et un abaissement du pH à 3,5 avec de l’acide citrique. Le jus peut être commercialisé sous forme de nectar, thé glacé ou boisson gazeuse, sans oublier une valorisation de ses coproduits (confiture, soupe, poudre, etc.). / The orientations of the Moroccan agricultural policy concerning the Green Morocco Plan, promote the development of the arid zones and the development of crops that adapt to global warming. The prickly pear cactus is a plant which is adapted to the arid climate and still untapped in Morocco. Prickly pear cladodes contain bioactive components that have beneficial health effects. The juice extracted from cladodes of both species Opuntia ficus-indica(spineless) and Opuntia megacantha(spiny) was the subject ofthis work. The cladodes were harvested in the region of Marrakech (Ouled Dlim) in Morocco for three seasons (spring, summer and winter) between 2013 and 2014 to assess the effect of harvest time on the physico-chemical and biochemical composition and antioxidant activity. The yield of cladode juice varies within the seasons and species (63,39 –20,83 %). The physico-chemical and biochemical analyzes showed that cladode juice is rich in polyphenols (543 ± 1–456 ± 8mg GAE/mL), in ascorbic acid (17,60 ± 1,87 –22,88 ± 0,62 mg/100 mL) and in potassium (409,35 –44,23 mg/100mL) but poor in sugar (0,66 ± 0,01–1,45 ± 0,03 g/100 mL). HPLC analysis of phenolic compounds has shown that cladode juice is rich in flavonols namely isoquercetin and hyperoside (645,90 mg/mL and 164,50 mg/mL respectively). The antioxidant activity of cladode juice was measured with FRAP test (1,74 ± 0,07 –3,33 ± 0,02 μmol TE/mL) and the antiradical activity was carried out with the DPPH test (1,78 ± 0,03 –4,10 ± 0,02 μmol TE/mL ) and the ABTS test (12,78 ± 1,69 –23,10 ± 0,17 μmol TE/mL ). The correlation analysis indicated that there was a significant relationship (p<0,05) between the methods of analysis, species and seasons.Quantitative analysis of cladode juice harvested in March HPLC-DAD showed the presence of a significant quantity of flavonoids essentially isoquercetin and hyperoside. Results of these analyzes showed that cladode juice is rich in nutriments and has an antioxidant activity potential. The juice can be stored for 42 days at 4°C, after pasteurization at 95°Cfor 3 min in a water bath and lowering the pH to 3,5 with citric acid. Cladode juice can be used as nectar, iced tea or soft drink and with a valorization of its coproducts (jam, soup, powder etc.).
167

Les enjeux de l’olivier en situations urbaine et périurbaine : nouvelles constructions territoriales et prospectives : cas du cordon littoral Centre–Sud tunisien / The stakes of the olive tree in urban and suburban situations, new territorial structures and prospective : the central and southern Tunisian coast

Jaouachi, Tahar 12 July 2016 (has links)
Alors que de nouveaux usages des espaces ruraux se développent sous l’effet combiné des dynamiques urbaines et touristiques, la question de l’effet de l’urbanisation sur les oliveraies du littoral tunisien est questionnée. L’hypothèse de base est que le développement économique et touristique important, associé à une urbanisation peu planifiée, met en danger l’oléiculture du littoral Centre-Sud tunisien, culture stratégique dans l’économie et la société du pays. L’objectif de la thèse est de comprendre les places (spatiales, économiques, culturelles, paysagères, etc.) du système de l’olivier. Il s’agit d’étudier les enjeux de l’olivier en situations urbaine et périurbaine. Dans une première partie est exposée la démarche conceptuelle, méthodologique et pratique qui permet d’appréhender les enjeux de l’agriculture urbaine et périurbaine et de l’olivier. Le concept du système de l’olivier est alors inscrit dans un méta-système littoral territorial afin de rendre compte des temporalités, du jeu des acteurs locaux publics et privés autour de la place et des fonctions de l’activité oléicole. Ce concept est à la base de l’analyse systémique de l’oléiculture littorale urbaine et périurbaine du cordon littoral, dont les résultats sont développés pour saisir les facteurs de résistance et les nouvelles valeurs de l’olivier. Il est tout d’abord montré comment les interactions dynamiques entre des événements d’ordre démographique, socioéconomique et politique ont conduit à transformer l’espace oléicole littoral en espace mixte, agricole, urbain et touristique. Mais, les transformations spatiales et les dynamiques agri-urbaines, conjuguées aux évolutions culturelles des populations locales se traduisent par l’émergence de nouveaux rapports, non seulement contradictoires, mais aussi reliés : environnementaux, patrimoniaux, paysagers, etc. Dans cette perspective, les notions de ressources paysagères et patrimoniales deviennent un nouveau point de recherche pour saisir les atouts et les limites des processus mis en oeuvre. Ceci oriente la recherche vers des questions nouvelles, notamment celle de la valorisation territoriale qui s’appuient sur les potentialités et les nouvelles valeurs de l’olivier (patrimoniale, paysagère et économique), tout en tirant profit du développement touristique sur le littoral / When new uses of rural areas are developed through a combination of urban and tourist dynamics, the question of the impact of urbanization on the olive groves of the Tunisian coast is presents itself. The basic assumption is that the major economic and tourism development, coupled with an uncontrolled urbanization, and supported by inadequate policies, create a threat on the olives growing along the central and southern Tunisian coast, this is a strategic culture for the national economy. The aim of the thesis is to understand the places (spatial, economic, cultural, etc.) of the olive tree system, and to study the issues of olive trees in urban and suburban situations. In the first part is demonstrated the approach and methodology that allows understanding the issues of the urban and suburban agriculture and olive groves. The concept of the olive tree system is then placed in a coastal metasystem to understand the time frames, the interactions between the actors around the place and the functions of the olive sector. This concept is the base of a systemic analysis of olive groves. The results are, then, developed to study the factors of resistance and new values of the olive tree. It is first shown how the dynamic interactions between the demographic, the socio-economic and the political events led to transform the olive’s landscape coastline to a mixed area: agricultural, economic and tourism. However, the territorial transformations and the different dynamics, combined with the cultural developments can be observed in the emergence of new interactions, not only contradictory but also affective: environmental and patrimonial. The landscape and heritage resources notions have become a new subject of research to understand the potential and new values of olive tree
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Application des électrotechnologies pour une valorisation optimisée de la betterave à sucre dans un concept de bioraffinerie / Application of electrotechnologies for an optimized valorization of sugar beet in biorefinery concept

Almohammed, Fouad 24 January 2017 (has links)
Ce travail de thèse concerne l’utilisation des électrotechnologies pour une valorisation optimisée de la betterave à sucre conformément au concept de bioraffinerie. Les électro-technologies appliquées sont les champs électriques pulsés (CEP) et les décharges électriques de haute tension (DEHT). L’étude s’attache d’une part à l’optimisation d’un procédé alternatif pour l’extraction du sucre par pressage alcalin à froid assisté par CEP. D’autre part, elle propose des nouvelles voies pour la valorisation de deux coproduits de l’industrie betteravière qui sont les radicelles et la pulpe de betterave. Dans la première partie, le traitement électrique par CEP couplé au chaulage permet une meilleure désintégration du tissu betteravier. Il permet d’accélérer les cinétiques du pressage, d’améliorer le rendement ainsi que la qualité du jus et d’alléger la procédure de purification en aval de l’extraction. Une étude paramétrique d’optimisation a permis d’identifier le meilleur itinéraire d’application de ce nouveau procédé d’extraction. Les cossettes fraîches de betterave sont prétraitées par CEP à 600 V/cm pour 10 ms (Q = 2,7 Wh/kg). Les cossettes électroporées sont ensuite pressées à froid pour extraire 75 % du jus. Les cossettes pressées subissent un pressage alcalin avec 10 % du lait de chaux. Afin d’extraire le sucre résiduel dans le gâteau de pressage obtenu, deux étapes de pressage supplémentaires avec une étape intermédiaire d’hydratation sont nécessaires. Ce procédé optimisé permet de bien épuiser les cossettes en sucre (perte en sucre de 0,23 % et matière sèche de pulpes de 39 %) pendant une courte durée d’extraction (30 min) avec un faible soutirage (108 %) par rapport au procédé de diffusion. Il permet ainsi des économies significatives de matière et d’énergie surtout pour les étapes d’extraction du jus et de séchage de pulpes. Par rapport au procédé conventionnel, le gain énergétique s’élève à 91,96 × 106 kWh pour une usine traitant 10 000 t/j de betteraves pendant une campagne de 110 jours. De plus, le procédé proposé permet de simplifier la procédure de purification et de réduire de 50 à 60 % la quantité de chaux utilisée. Dans la deuxième partie de cette étude, deux procédés de transformation ont été proposés et optimisés à l’échelle laboratoire pour la valorisation des radicelles et de la pulpe de betterave à sucre. Les radicelles ont été utilisées pour produire du bioéthanol. Le jus brut de radicelles a été extrait par pressage à froid assisté par CEP. La production du bioéthanol a été achevée par fermentation alcoolique. Le prétraitement par CEP (450 V/cm, 10 ms) a permis d’accélérer la cinétique de pressage, d’augmenter le rendement en solutés (79,85 % vs. 16,8 %) et d’obtenir un jus plus concentré (10 % vs. 5,2 %). Le procédé optimisé permet de produire environ 41,75 L de bioéthanol par tonne de radicelles lorsque l’on applique un prétraitement par CEP contre seulement 8,2 L de bioéthanol sans prétraitement électrique confirmant ainsi le potentiel de ce nouveau schéma de valorisation. La pulpe de betterave déshydratée ayant une matière sèche de 92,8 % a été utilisée pour l’extraction de pectines. L’étude réalisée a montré que l’application d’un prétraitement par DEHT permet d’intensifier l’extraction des pectines. Le gain relatif de rendement en pectines est de 25,3 % pour une énergie consommée de 76,2 kJ/kg. Le schéma de bioraffinage proposé pourra aider au maintien de la filière betteravière en France après la suppression de système de quotas sucriers dans l’Union européen qui entrera en vigueur le 1er octobre 2017. / This work discusses the use of electrotechnologies for an optimized valorization of sugar beet according to the concept of biorefinery. The applied electrotechnologies are pulsed electric fields (PEF) and high-voltage electrical discharges (HVED). The study firstly aims at optimizing an alternative method for sugar extraction by PEF assisted cold alkaline pressing. On the other hand, it proposes new ways for valorizing two by-products of sugar beet industry, which are sugar beet tails and pulps. In the first part, PEF treatment combined with liming leads to a better disintegration of beet tissue. It permits accelerating of pressing kinetics, improvement of juice yield and quality, and reduction of subsequent purification procedure. A parametric optimization study identified the best application itinerary of the proposed extraction process. Fresh sugar beet cossettes are pretreated by PEF at 600 V/cm for 10 ms (Q = 2.7 Wh/kg). The electroporated cossettes are then pressed to extract 75% of intracellular juice. Compressed cossettes are subjected to an alkaline pressing with 10% lime milk. In order to extract the residual sucrose in the obtained press-cake, two additional steps of pressing with an intermediate hydration are required. This optimized process allows well exhausting the sugar cossettes (sugar loss of 0.23% and pulp dry matter of 39%) for a short extraction (30 min) and with low draft (108%) compared to diffusion method. Thus, it allows substantial saving in materials and energy especially for juice extraction and pulp drying. Compared to the conventional method, the energy saving amounted to 91.96 × 106 kWh for a sugar beet factory treating 10 000 tons per day for a campaign of 110 days. In addition, the proposed method simplifies the purification procedure of raw juice and reduces the used amount of lime from 50 to 60%. In the second part of this study, two processing methods were proposed and optimized at lab-scale for valorization of sugar beet tails and pulps. Sugar beet tails were used to produce bioethanol. Raw juice of beet tails was extracted by PEF assisted cold pressing. Bioethanol production was then done by alcoholic fermentation. Pretreatment of beet tails with PEF (450 V/cm, 10 ms) permits accelerating the pressing kinetics, increasing the yield of solutes (79.85% vs. 16.8%), and leads to a more concentrated juice (10% vs. 5.2%). The optimized process permits the production of about 41.75 L of bioethanol per ton of beet tails when PEF pretreatment is applied against only 8.2 L of bioethanol without PEF confirming the potential of this new valorization scheme. Dried beet pulp having a dry matter of 92.8% was used for pectin recovery. The present study showed that the application of HVED pretreatment leads to intensify pectin extraction. The relative gain of pectin yield is 25.3% with an energy consumption of 76.2 kJ/kg. The proposed biorefinery scheme could protect the sugar beet industry in France after the suppression of the sugar quota system in the European Union, which will take effect on 1st October 2017.
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Traitement à haute pression et haute température de déchets de métaux lourds vers de nouveaux matériaux stables / High pressure and high temperature treatment of heavy metal waste, towards new stable materials

Karnis, Aurélie 08 October 2009 (has links)
Les REFIOM (Résidus d'Epuration des Fumées d'Incinération des Ordures Ménagères) issus de l'incération des déchets ménagers contiennent des métaux lourds comme le plomb ou le cadmium et sont en France uniquement stockés en centre d'enfouissement technique de classe 1 pour dangereux, en étant stabilisés par une vitrification. Afin de trouver des solutions pour le stockage ou la valorisation à long terme des REFIOM sans danger pour l'environnement, nous avons ciblé les vitrocéramiques et les céramiques frittées à hautes températures et hautes pressions. Nous avons utilisé des méthodes de la minéralogie physique par l'intermédiaire de synthèses à hautes températures, de synthèses à hautes températures et à hautes pressions en autoclave à chauffage externe, d'observations en microscopie électronique à balayage, de microanalyses chimiques EDX (Energy Dispersive X-Ray spectrometry), d'analyses en microsondes, de caractérisation structurale par diffraction de rayons X et d'expériences de lixiviation dynamique. Nous avons mis au point des protocoles de synthèses et d'analyses. Par ce biais, nous constatons pour les vitrocéramiques que le plomb ou le cadmium sont incorporés dans des cristallites et dans des nouvelles phases cristallines, eux-mêmes englobés dans une matrice vitreuse. Cette voie dite "double barrière" (cristaux + verre) semble prometteuses pour l'immobilisation du plomb et du cadmium (au regard des analyses EDX et des expériences de lixiviation). Pour les céramiques frittées, comme pour les SYNROC (SYNthetic ROCk) synthétisées pour les déchets nucléaires, de nouvelles phases cristallines incorporant Pb et Cd sont observées et seraient a priori résistantes pour le stockage de ces éléments toxiques. Dans ces deux cas de nouveaux matériaux capables d'incorporer massivement du plomb et du cadmium ont été mis en évidence. Des tests de durabilité permettront d'envisager une valorisation éventuelle de tels matériaux / MSWI 5Municipal Solide Waste Incinerator) fly ashes from the incineration of domestic waste contain heavy metals such as lead or cadmium. In France, these fly ashes are only stored under vitrified forms in class-1 type landfills for hazardous waste. In order to find solutions for long-term storage or valorization of the MSWI fly ashes, we studied glass-ceramics and sintered ceramics at high pressures and/or hight temperature. We used methods of mineral physics to : synthetize at high temperature, synthetize at higt temperature and high pressure using autoclaves with external heating system, observe by electron microcopy, make EDX (Energy Dispersive X-Ray spectrometry) chemical microanalysis, make microprobe analysis, structurally characterize and perform leaching test. We established experimental protocols for the synthesis and analysis of produced materials. For glass-ceramics, we observe that lead and cadmium are incorporated inside expected crystallites and new crystal phases, themselves embedded by a glassy matrix. This so-called "double barrier" (crystals + glass) is a promising way towards a substainable of lead and cadmium (after EDX analysis and leaching experiements). For sintered ceramics, as for the SYNROC (SYNthetic ROCk) with nuclear waste, new crystal phases incorporating Pb and Cd are found and might display a high resistant for the storage of these toxic elements. In both cases, new materials incorporating large amounts of lead and cadmium were formed. Durability tests may give new ways for a valorization of such materials
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Contribution à la modélisation du comportement mécanique d'un matériau hétérophasé rematérialisé issu d'un mâchefer d'incinération d'ordures ménagères : valorisation en Génie Civil / Contributions to the modeling of the mechanical behavior of the heterophase rematerialize material from a municipal solid waste incineration : Recycling in civil engineering

LE, Ngoc Hung 15 December 2011 (has links)
Les mâchefers sont les résidus solides issus de la combustion des ordures ménagères dans des fours d’usine d’incinération. L’utilisation des mâchefers dans le domaine du Génie Civil est une voie de valorisation très intéressante car les quantités d’ordures ménagères sont de plus en plus importantes alors que les matériaux utilisés dans les travaux publics se raréfient. Les mâchefers ont été utilisés depuis des dizaines d’années dans le domaine du Génie Civil. Cependant, les caractéristiques mécaniques du matériau « mâchefer » ne sont pas très bien connues. Ce travail de thèse contribue à l’amélioration des connaissances des caractéristiques mécaniques des mâchefers.Après une caractérisation géotechniques (paramètres de nature, paramètres mécaniques, paramètres d’état), chimiques et environnementales, le potentiel d’utilisation de ces mâchefers est évalué selon la Circulaire du 9 mai 1994 et selon le Guide technique SETRA-LCPC 2000 « Réalisation des remblais et des couches de forme ».Dans la partie expérimentale, des essais oedométriques et triaxiaux sont effectués. En ce qui concerne des essais oedométriques, l’effet de l’énergie de compactage et de l’immersion des éprouvettes ainsi que l’effet de la vitesse de chargement de l’essai sont évalués. L’effet de la vitesse de chargement est également étudié par des séries d’essais triaxiaux. Grâce aux essais triaxiaux, les paramètres mécaniques comme le module d’Young, le coefficient de Poisson, l’angle caractéristique, l’angle de dilatance, la cohésion et l’angle de frottement ont été ainsi déterminés. Ces paramètres mécaniques propres au mâchefer étudié pourront être intégrés dans un schéma de dimensionnement spécifique aux structures de chaussées à base de mâchefers. Ces principaux paramètres permettent d’évaluer l’influence de la pression de confinement effective. Les évolutions du module de déformation selon la déformation axiale et de la variation du déviateur de pression selon la pression moyenne sont également étudiées. Un ensemble de points caractérisant l’état limite a été déterminé à partir des essais triaxiaux. Il caractérise la forme de la surface de charge de ce type de mâchefer.Enfin, les essais triaxiaux ont été simulés. Cette partie du travail contribue à la modélisation du comportement mécanique des mâchefers. Le modèle de Mohr-Coulomb et de Nova sont choisis pour caractériser l’évolution de matériau « mâchefer » sous l’effet d’actions mécaniques extérieures. Ce sont des exemples types de modèles de comportement des sols complètement identifiables uniquement sur des essais triaxiaux classiques. La simulation des essais triaxiaux est réalisée à l’aide du progiciel CESAR-LCPC. Les résultats de modélisations obtenues sont très prometteurs. / Bottom ash is the solid residua coming from domestic waste combustion in the furnace of incineration factory. The utilization of bottom ash in the field of Civil Engineering is necessary because the municipal wastes are increasing causes many environmental problems while the materials of Civil Engineering dwindle. The bottom ash was used for a decade in the field of civil engineering; however the mechanical characteristics of material “bottom ash” are not very well known. This work of thesis contributes to improving knowledge of the mechanical characteristics of bottom ash. After the determination of the geotechnical characteristics (parameters of nature, mechanical parameters, parameters of state), chemical and environmental characteristics, the potential of use of these bottom ash is evaluated according to the « Circulaire de 9 Mai, 1994 » and according to the technical guide SETRA-LCPC 2000 « Réalisation des remblais et des couches de forme ».In the experimental part, the oedometric and triaxial tests are carried out. For oedometric tests, the effect of compaction energy and immersion of specimens as well as the effect of the loading rate of the test were evaluated. The effect of loading rate is also evaluated by some sets of triaxial tests. From the triaxial tests, the mechanical parameters such as the Young’s modulus, the Poisson‘s ratio, the characteristic angle, the dilatancy angle, the cohesion and the friction angle were determined. These mechanical properties are specific to the material and can be integrated in a diagram of dimensioning specific to the structures of roadways based on bottom ash. The studied principal parameters allow us to evaluate the influence of the effective confining pressure. The evolution of the deformation modulus versus to the axial deformation and finally, the variation of the deviator stress versus to the mean effective pressure were also analyzed. A set of points of the yielding state was determined from triaxial tests and it specifies significantly the shape of yielding surface of our bottom ash.Finally, the triaxial tests were simulated numerically. This part is a contribution to the modelling of the mechanical behaviour of bottom ash. The model of Mohr-Coulomb and Nova were chosen to characterize the evolution of the material “bottom ash” under the influence of external mechanical actions. These are typical examples of model soil completely identifiable only through traditional triaxial tests. The simulation of triaxial tests is carried out using the CESAR-LCPC software. The results are found to be promising.

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