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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.
141

Διαμόρφωση μεθοδολογίας και εκτίμηση της κατάστασης των ιχθύων Aphanius fasciatus & Valencia letourneuxi (Παράρτημα ΙΙ, Οδηγία 92/43/ΕΟΚ) στην περιοχή δικαιοδοσίας του Φορέα Διαχείρισης Υγροτόπων Κοτυχίου-Στροφυλιάς

Θανασάκης, Δημήτριος 03 1900 (has links)
Τα Κράτη Μέλη της Ευρωπαϊκής Ένωσης υποχρεούνται να συντάσσουν ανά εξαετία εθνικές εκθέσεις για τον έλεγχο της εφαρμογής της Οδηγίας των Οικοτόπων (92/43/ΕΟΚ). Οι εκθέσεις αυτές, όπως αναφέρεται στο Άρθρο 17 της Οδηγίας, περιλαμβάνουν κατά κύριο λόγο πληροφορίες σχετικά με τα μέτρα διατήρησης, καθώς και την εκτίμηση των επιπτώσεων αυτών των μέτρων στην κατάσταση διατήρησης των τύπων οικοτόπων και ειδών Κοινοτικού ενδιαφέροντος. Έχοντας δεδομένο το παραπάνω, έγινε ανάλυση των υπαρχόντων στοιχείων και συγκέντρωση νέων πρωτογενών δεδομένων για την εκτίμηση των ειδών Aphanius fasciatus & Valencia letourneuxi (Παράρτημα ΙΙ, Οδηγία 92/43/ΕΟΚ) στην περιοχή των λιμνοθαλασσών Αράξου, Κοτυχίου, Πρόκοπου που εντάσσονται στο Εθνικό Πάρκο Υγροτόπων Κοτυχίου-Στροφυλιάς. Η μελέτη εμπεριέχει τρείς συνιστώσες. Η πρώτη αφορά στη διαμόρφωση της απαραίτητης υποδομής και μεθοδολογίας για την αποτύπωση της κατάστασης των πληθυσμών των προαναφερθέντων ειδών, σύμφωνα με το Άρθρο 17 της Οδηγία 92/43/ΕΟΚ. Η οδηγία προβλέπει, πέρα από την συλλογή και επεξεργασία δεδομένων που αφορούν πληθυσμούς προστατευόμενων ειδών και την ταυτόχρονη παρουσίασή τους σε περιβάλλον Συστημάτων Γεωγραφικών Πληροφοριών (G.I.S), σύμφωνα με συγκεκριμένες προδιαγραφές της κεντρικής βάσης υποδοχής της Ευρωπαϊκής Ένωσης. Η δεύτερη συνιστώσα αφορούσε στο σχεδιασμό και την υλοποίηση δειγματοληψιών σε συγκεκριμένους οικοτόπους της περιοχής έτσι ώστε να καταστεί δυνατή η συλλογή δεδομένων που χαρακτηρίζουν τους συγκεκριμένους πληθυσμούς. Η τρίτη συνιστώσα επικεντρώθηκε στην ανάλυση της προϋπάρχουσας και της νέας πληροφορίας με στόχο την εκτίμηση της κατάσταση των πληθυσμών, την αξιολόγηση των παραγόντων που επηρεάζουν το μέλλον τους και τις προτάσεις για τη διατήρηση-βελτίωση της κατάστασης της περιοχής. Τα αποτελέσματα της μελέτης για το Aphanius fasciatus μας οδηγούν στο συμπέρασμα ότι οι πληθυσμοί είναι σε καλή κατάσταση από άποψη αφθονίας και ότι δεν συντρέχουν ιδιαίτεροι λόγοι απειλών άρα και ιδιαίτερα μέτρα διαχείρισης. Για το είδος Valencia letourneuxi το οποίο δεν βρέθηκε στην περιοχή μελέτης, καταδεικνύει σε συνδυασμό με προγενέστερες μελέτες, τον περιορισμό της γεωγραφικής εξάπλωσης του είδους με την εξαφάνιση ή κοντά στην εξαφάνιση των δυτικότερων και νοτιότερων πληθυσμών του είδους. Για το λόγο αυτό και αν δεν βρεθεί στο εγγύς μέλλον ίσως πρέπει να εφαρμοστούν κατάλληλα διαχειριστικά μέτρα που θα επαναφέρουν τους πληθυσμούς στην πρότερη κατάστασή τους. / The Member States of the European Union are required to prepare every six years national reports on the monitoring the implementation of the Habitats Directive (Directive 92/43/EEC). These reports, as mentioned in Article 17 of the Habitats Directive, include primarily information concerning conservation measures and impact assessment of these measures on the conservation status of habitat types and species of Community interest. Taking into account the above, were analyzed the existing data, new data were collected for the monitoring of the species Aphanius fasciatus & Valencia letourneuxi (Annex II, Directive 92/43/EEC) in the region of the lagoons Araxos, Kotychi and Prokopos of the National Park Kotychi-Strofylia. The study comprises three components. The first relates to the formation of the necessary infrastructure and methodology for the survey on the condition of the populations of the two species, in accordance with the Article 17 of Directive 92/43/EEC. The Directive provides, except from the collection and processing of data on populations of protected species, also the simultaneous presentation in GIS environment, in compliance with the specific requirements of the European Union central receiving center. The second component included the design and implementation of sampling at specific habitats region in order to collect data characterizing specific populations. The third component focused on the analysis of pre-existing and new information in order to assess the status of populations, the evaluation of factors affecting their future and proposals for maintaining-improving the situation in the region. The results of the study on Aphanius fasciatus, lead us to conclude that the populations are in good condition in terms of abundance and there are no particular threats, therefore special management measures are not nedeed. On the other hand, Valencia letourneuxi was not found in the study area, indicated similarity to previous studies, the limited distribution of the species with possibility of extinction or near extinction of the western and southern populations. For this reason, and if not found in the near future, necessary management measures are required to restore the populations to their former condition.
142

Cartas pueblas de las morerías valencianas y documentación complementaria /

Febrer Romaguera, Manuel Vicente, January 1900 (has links)
Texte remanié de: T. doct.--Facultad de Geografía e historia--Universidad literaria de Valencia, 1984. Titre de soutenance : Organización municipal de las morerías valencianas.
143

Propriedades eletrônicas do monocalcogenetos de Sm e de ligas do tipo Sm1-xMxS

Strauch, Irene Maria Fonseca January 1981 (has links)
Apresentamos um modelo teórico para explicar as tran sições de valéncia do Sm nas ligas Smi _ x M xS, onde M é um metal de transição (por ex. Y ou La), como uma função da concentração x. O sistema é descrito por um modelo de duas bandas: uma banda de largura nula e de energia E0 (o nível 4f do Sm) e uma banda de condução, a qual é tratada na aproximação do potencial coerente (CPA). Os elétrons 4f interagem entre si via uma repulsão coulombiana finita U, que separa a banda f em duas sub-bandas de energias E0 e Eo+U. Consi dera-se que as bandas f e de condução se hibridizam, sendo V o parâmetro de hibridização. Com este mo delo é possível obter uma transição continua de um estado funda mental não-magnético a um estado não magnético ou magnético, con forme se varia a razão U/V. A variação de valência como uma função da pressão nos monocalcogenetos de Sm (x = O) é também calculada. O modelo usa do é uma extensão do descrito acima, ao qual nOs incluimos uma repulsão coulombiana G entre elétrons f e de condução, mantendo finito o valor de U. Para diferentes valores de G/V obtemos tran sições de primeira ou de segunda ordem de um estado semicondutor a um estado metálico. A resistividade elétrica em ambas as fases é também calculada como uma função da temperatura e os re sultados teoricos obtidos estão em boa concordância com os experimentais. / We present a theoretical model to explain the valence transitions of Sm in Sm1-xMxS alloys, where M is a transition metal (e.g. Y or La) as a function of the concentration x. The system is described by a two-band model: a zero width band of energy E0 (the 4f-level of Sm) and a conduction band, which is treated in the coherent potencial approximation (CPA). The 4felectrons interact between them via a finite intra-atomic coulomb repulsion U, which splits the f-band in two sub-bands at energies E0 and Eo+U. The f -and conduction bands hybridize, being V the hybridization parameter. Within this model it is possible to obtain a continuous valence transition from a non- -magnetic to a non-magnetic or a magnetic ground-state, varying the ratio U/V. The change of valence as a function of pressure in the Sm monochalcogenides (x =0) is also computed. The model used is an extension of the one described above, in which we include a Coulomb repulsion G between f - and conduction electrons, preserving the finite value of U. For different values of G/V we obtain first or second order transitions from a semiconducting to a metallic state. The electrical resistivity in both fases as a function of temperature is also computed and the theoretical results obtained are in good agreement with the experimental ones.
144

Propriedades eletrônicas do monocalcogenetos de Sm e de ligas do tipo Sm1-xMxS

Strauch, Irene Maria Fonseca January 1981 (has links)
Apresentamos um modelo teórico para explicar as tran sições de valéncia do Sm nas ligas Smi _ x M xS, onde M é um metal de transição (por ex. Y ou La), como uma função da concentração x. O sistema é descrito por um modelo de duas bandas: uma banda de largura nula e de energia E0 (o nível 4f do Sm) e uma banda de condução, a qual é tratada na aproximação do potencial coerente (CPA). Os elétrons 4f interagem entre si via uma repulsão coulombiana finita U, que separa a banda f em duas sub-bandas de energias E0 e Eo+U. Consi dera-se que as bandas f e de condução se hibridizam, sendo V o parâmetro de hibridização. Com este mo delo é possível obter uma transição continua de um estado funda mental não-magnético a um estado não magnético ou magnético, con forme se varia a razão U/V. A variação de valência como uma função da pressão nos monocalcogenetos de Sm (x = O) é também calculada. O modelo usa do é uma extensão do descrito acima, ao qual nOs incluimos uma repulsão coulombiana G entre elétrons f e de condução, mantendo finito o valor de U. Para diferentes valores de G/V obtemos tran sições de primeira ou de segunda ordem de um estado semicondutor a um estado metálico. A resistividade elétrica em ambas as fases é também calculada como uma função da temperatura e os re sultados teoricos obtidos estão em boa concordância com os experimentais. / We present a theoretical model to explain the valence transitions of Sm in Sm1-xMxS alloys, where M is a transition metal (e.g. Y or La) as a function of the concentration x. The system is described by a two-band model: a zero width band of energy E0 (the 4f-level of Sm) and a conduction band, which is treated in the coherent potencial approximation (CPA). The 4felectrons interact between them via a finite intra-atomic coulomb repulsion U, which splits the f-band in two sub-bands at energies E0 and Eo+U. The f -and conduction bands hybridize, being V the hybridization parameter. Within this model it is possible to obtain a continuous valence transition from a non- -magnetic to a non-magnetic or a magnetic ground-state, varying the ratio U/V. The change of valence as a function of pressure in the Sm monochalcogenides (x =0) is also computed. The model used is an extension of the one described above, in which we include a Coulomb repulsion G between f - and conduction electrons, preserving the finite value of U. For different values of G/V we obtain first or second order transitions from a semiconducting to a metallic state. The electrical resistivity in both fases as a function of temperature is also computed and the theoretical results obtained are in good agreement with the experimental ones.
145

Propriedades eletrônicas do monocalcogenetos de Sm e de ligas do tipo Sm1-xMxS

Strauch, Irene Maria Fonseca January 1981 (has links)
Apresentamos um modelo teórico para explicar as tran sições de valéncia do Sm nas ligas Smi _ x M xS, onde M é um metal de transição (por ex. Y ou La), como uma função da concentração x. O sistema é descrito por um modelo de duas bandas: uma banda de largura nula e de energia E0 (o nível 4f do Sm) e uma banda de condução, a qual é tratada na aproximação do potencial coerente (CPA). Os elétrons 4f interagem entre si via uma repulsão coulombiana finita U, que separa a banda f em duas sub-bandas de energias E0 e Eo+U. Consi dera-se que as bandas f e de condução se hibridizam, sendo V o parâmetro de hibridização. Com este mo delo é possível obter uma transição continua de um estado funda mental não-magnético a um estado não magnético ou magnético, con forme se varia a razão U/V. A variação de valência como uma função da pressão nos monocalcogenetos de Sm (x = O) é também calculada. O modelo usa do é uma extensão do descrito acima, ao qual nOs incluimos uma repulsão coulombiana G entre elétrons f e de condução, mantendo finito o valor de U. Para diferentes valores de G/V obtemos tran sições de primeira ou de segunda ordem de um estado semicondutor a um estado metálico. A resistividade elétrica em ambas as fases é também calculada como uma função da temperatura e os re sultados teoricos obtidos estão em boa concordância com os experimentais. / We present a theoretical model to explain the valence transitions of Sm in Sm1-xMxS alloys, where M is a transition metal (e.g. Y or La) as a function of the concentration x. The system is described by a two-band model: a zero width band of energy E0 (the 4f-level of Sm) and a conduction band, which is treated in the coherent potencial approximation (CPA). The 4felectrons interact between them via a finite intra-atomic coulomb repulsion U, which splits the f-band in two sub-bands at energies E0 and Eo+U. The f -and conduction bands hybridize, being V the hybridization parameter. Within this model it is possible to obtain a continuous valence transition from a non- -magnetic to a non-magnetic or a magnetic ground-state, varying the ratio U/V. The change of valence as a function of pressure in the Sm monochalcogenides (x =0) is also computed. The model used is an extension of the one described above, in which we include a Coulomb repulsion G between f - and conduction electrons, preserving the finite value of U. For different values of G/V we obtain first or second order transitions from a semiconducting to a metallic state. The electrical resistivity in both fases as a function of temperature is also computed and the theoretical results obtained are in good agreement with the experimental ones.
146

Descascamento de frutas cítricas pelo uso do tratamento hidrotérmico / Peeling of citric fruits by using Hydrothermal Treatment

Ana Luiza Pinheiro 16 May 2008 (has links)
O processamento de citros se justifica pela dificuldade de descascamento destes frutos. Estudos de descascamento de laranja \'Pêra\' realizados na ESALQ-USP vêm mostrando o potencial do uso do tratamento hidrotérmico para facilitar o descascamento desta variedade. As laranjas são imersas em água a 50ºC por 8 minutos, isto facilita o descascamento e não afeta a qualidade da fruta. Entretanto, é necessário estudar outros tempos de imersão para flexibilizar o uso desta técnica em escala industrial, bem como estendê-la a outras variedades. O objetivo deste trabalho foi adequar a tecnologia de descascamento de frutas cítricas pelo uso do tratamento hidrotérmico, bem como avaliar sua influência na qualidade fisiológica, físico-química, microbiológica e sensorial de laranjas \'Pêra\', laranjas \'Valência\' e tangores \'Murcott\'. Também foram avaliados o tempo de descascamento, o rendimento em frutos comercializáveis e a temperatura interna dos frutos durante o tratamento. Os frutos foram lavados, sanitizados, resfriados a 5ºC por 12 horas, submetidos ao tratamento hidrotérmico e descascados. O tratamento hidrotérmico consistiu em colocar os frutos em banho-maria a 50ºC por 5 (somente para o tangor \'Murcott\'), 10, 15, 20, 25 e 30 minutos. Posteriormente, os frutos foram descascados retirando-se a parte peduncular com a faca e, em seguida, o flavedo foi retirado, manualmente, junto com o albedo. Os frutos sem tratamento hidrotérmico (controle) foram descascados retirando-se primeiramente o flavedo, e depois o albedo cuidadosamente para causar o mínimo de injúria possível. Os frutos foram analisados durante seis dias de armazenamento a 5ºC. Os experimentos foram conduzidos separadamente para cada fruta cítrica e de acordo com cada tipo de análise. Foram utilizados delineamentos inteiramente ao acaso e em blocos casualizados, adequados para cada variável analisada. O tratamento hidrotérmico provocou alterações na atividade respiratória dos frutos somente nas primeiras horas após o processamento. A temperatura interna dos frutos (medida a 2 cm de profundidade em relação ao epicarpo) após 30 minutos de tratamento atingiu aproximadamente 35ºC, temperatura comumente observada em algumas etapas da cadeia de comercialização dos frutos. A coloração externa das laranjas sem tratamento apresentou maior valor de luminosidade (L) quando comparadas às frutas tratadas. Não houve alterações nas outras características físico-químicas e nas características microbiológicas dos frutos. O tratamento não alterou o sabor e melhorou a aparência em relação aos frutos sem tratamento devido à ausência de resquícios de albedo nos frutos. Além disso, o tratamento diminuiu em até 78% o tempo de descascamento dos frutos tratados para a laranja \'Pêra\', em até 75% para a laranja \'Valência\' e em até 57% para o tangor \'Murcott\', quando comparados aos frutos sem tratamento, e aumentou o rendimento em frutos comercializáveis. O tratamento hidrotérmico realizado até 30 minutos a 50ºC pode ser utilizado como técnica de descascamento para laranja \'Pêra\', laranja \'Valência\' e tangor \'Murcott\'. / The citrus fruit processing is justified for the difficulty of peeling of these fruits. Studies of peeling of \'Pera\' sweet orange fruit accomplished at ESALQ-USP are showing the potential of the use of the hydrothermal treatment to facilitate the peeling of this variety. The oranges are immersed in hot water at 50ºC for 8 minutes. This process to make easy the peeling and it doesn\'t affect the quality of the fruit. However, it is necessary to study other immersion times to make flexible the use of this technique in industrial scale, as well as to extend it for other varieties. The purpose of this work was to adapt the technology of peeling of citric fruits for the use of the hydrothermal treatment, as well as to evaluate the influence of the hydrothermal treatment in the physiological, physicochemical, microbiologic and sensorial qualities of \'Pera\' sweet orange, \'Valencia\' sweet orange and \'Murcott\' tangor. The peeling time, the yield of marketable fruits and the internal fruit temperature were also evaluated during the treatment. Fruits were washed, sanitized, cooled at 5ºC for 12 hours, submitted to hydrothermal treatment and peeled. The hydrothermal treatment consisted of putting fruits in water-bath at 50ºC for 5 (only for \'Murcott\' tangor), 10, 15, 20, 25 and 30 minutes. Then, fruits were peeled by first opening a gap on the peduncular region with a knife and then, the flavedo was removed, manually, with the albedo. Fruits with no hydrothermal treatment (control) were peeled by first removing the flavedo and then, the albedo was removed carefully to cause the less of injuries possible. The fruits were analyzed for six days of storage at 5ºC. The experiments were carried out separately for each citric fruit and in agreement with each analysis type. The experimental designs used were completely randomized and in randomized blocks, appropriate for each analyzed variable. Hydrothermal treatment caused changes in respiratory activity just in first hours after treatment. Internal fruit temperature (evaluated at 2 cm depth in relation to the epicarp) after 30 minutes of treatment reached 35ºC approximately, temperature commonly observed in some stages of the commercialization\'s chain of the fruits. The external coloration of the oranges without treatment presented larger value of brightness (L) when compared to the treated fruits. There were no changes in the others physicochemicals and microbiologics characteristics of the fruits. The treatment did not change the flavor and it improved the appearance in relation to the fruits without treatment due to the lower albedo residue in the fruits. Besides, the treatment decreased in up to 78% the peeling time of the treated fruits for the \'Pera\' sweet orange, in up to 75% for the \'Valencia\' sweet orange and in up to 57% for the \'Murcott\' tangor, when compared to the fruits without treatment, and it increased the yield of marketable fruits. The hydrothermal treatment accomplished up to 30 minutes at 50ºC can be used as peeling technique for \'Pera\' sweet orange, \'Valencia\' sweet orange and \'Murcott\' tangor.
147

Géodynamique et impact de la crise d'érosion et de salinité Messinienne sur les transferts sédimentaires (bassin de Valence, bassin Adriatique) / Perched basins of Mediterranean Sea : geodynamic, and impact of the Messinian salinity crisis on the sedimentary fluxes (Valencia and Adriatic basins)

Pellen, Romain 30 June 2016 (has links)
L’évolution géodynamique et physiographique de l’espace Méditerranéen, en particulier au sein des bassins bordiers de Valence et Adriatique, sont intimement liées à l’héritage anté-Néogène. L’identification de la segmentation des bassins et leur implication dans l’histoire tectonique et environnementale au Néogène, en particulier lors de la crise d’érosion et de salinité Messinienne (MESC - 5.96-5.32 Ma), reste cependant méconnus et font l’objet de ce travail de recherche. Afin de les mettre en lumière, nous proposons une vision complète du remplissage sédimentaire Néogène des deux bassins, sur la base d’une compilation de profils sismiques et de forages industriels. Nos résultats illustrent une segmentation du domaine Valence-Provençal en trois sousbassins d’âges, de subsidences et de nature crustales différentes. Un nouveau scénario cinématique est proposé à l’échelle des bassins Valencien et Algérien. Cette segmentation met en lumière lors de la MESC un système complet de vallées incisées fluviatiles long de plus de 270 km. Associé aux différents cortèges sédimentaires, un nouveau regard est jeté sur l’événement Messinien et le paradoxe d’ouverture du bassin de l’Ebre. Au sein du domaine Adria, l’héritage Mésozoïque contrôle en premier lieu les environnements néogènes, où deux dépocentres majeurs se distinguent de part et autre du seuil composite Apulien-Gargano-Pelagosa. La propagation des fronts de déformations Albanide et Apennin se surimpose à cet héritage et contrôle la sédimentation et les mouvements verticaux de ces dépocentres La période Messinienne est alors perçue comme une phase de réorganisation tectonique majeure, cette dernière se surimposant à la MESC. / The geodynamic evolution of the Mediterranean area, especially in the Valencia and Adriatic basins, is strongly influenced by its ante-Neogene history. The localization of existing thresholds at that time, and their impact on the following tectono- sedimentary evolutions still remain largely unknown. In this work, we will try to reconstruct this evolution and better understand the part of these thresholds, in particular during the Messinian Erosional and Salinity Crisis (MESC, 5.96-5.32 Ma). We provide here a complete view of the Neogene sedimentary infilling for the both Valencia and Adriatic basins thanks to a compilation of seismic profiles correlated to industrial boreholes.Our results allow us to individualize the Valence-Provençal domain into three subbasins whose ages, subsidence and crustal nature differ. A new kinematic and geodynamic scenario for the Valencia and Neogene Algerian basins is proposed here. This segmentation provides also information about MESC. We highlight a fully incised-valley system whose length reaches more than 270 km, the latter associated with the development of several system tracts. Overall, these interpretations lets us look the Ebro basin connection paradox from a different angle.The Mesozoic Apulian-Gargano-Pelagosa composite threshold mainly control the Neogene sedimentation in the Adria domain and distinguishes two main depocenters. The propagating of the Albanid and Apennine deformation fronts control also the evolution of vertical movements and the sedimentation. Our results imply that the Messinian period corresponds to a major tectonic and/or kinematic reorganization phase within which the MSC is a superimposed event.
148

Le bassin de Valence à la frontière des domaines ibérique et méditerranéen : évolution tectonique et sédimentaire du mésozoïque au cénozoïque / Valencia basin at the boundary between the Iberian and Mediterranean domains : tectono-sedimentary evolution from the Mezoique to the Cenozoique

Etheve, Nathalie 08 September 2016 (has links)
Le Bassin de Valence, situé à l’est de l’Ibérie et séparé du Bassin Algérien par le Promontoire Baléares, résulte d’une évolution polyphasée dans l’espace et dans le temps. Son histoire cénozoïque, celle d’un bassin d’arrière-arc Oligo-Miocène, est à présent reconnue. Toutefois cette extension se surimpose à plusieurs phases de rift observées à terre du Permien au Crétacé inférieur. Cette histoire plus ancienne demeure méconnue en mer malgré son importance dans l’héritage structural du bassin. Au sud du Bassin de Valence, le Bassin de Columbrets en témoigne en révélant d’épaisses séquences mésozoïques jusqu’alors incluses dans un « socle acoustique » indifférencié. Ce domaine permet donc le déchiffrage du mécanisme des évènements tectoniques qui se sont succédé du Mésozoïque à l’Est de l’Ibérie d’une part, au Cénozoïque en Méditerranée occidentale d’autre part.Basé sur une stratégie d’étude terre-mer, ce travail vise une meilleure compréhension (1) des processus tectoniques tertiaires modelant le sud du Bassin de Valence et la Méditerranée occidentale (2) de la réponse sédimentaire à des processus d’extension et d’hyper-extension au Mésozoïque (3) de l’importance de l’halocinèse lors la mise en place des structures sédimentaires et tectoniques.L’étude structurale d’Ibiza, l’île la plus méridionale du Promontoire Baléare, reconsidère le calendrier tectonique de la région ainsi que son intégration dans l’histoire géodynamique de la Méditerranée occidentale. Le rift Oligo-Miocène décrit dans le Bassin de Valence et initié par le Système de Rifts Cénozoïques Européens a été observé sur Ibiza. Cet évènement est suivi au Miocène Moyen d’une déformation compressive localisée par les failles normales précédemment formées. La comparaison avec le calendrier tectonique des Kabylies en Algérie montre que cette déformation compressive, qui épargne le Bassin Algérien, résulte de la convergence Europe-Afrique. Des cartes rétro-tectoniques intègrent ces évènements dans le contexte géodynamique de la Méditerranée occidentale depuis l’Oligocène.L’étude des séries Mésozoïques effectuées à terre et en mer (grâce à l’interprétation de données sismiques et de forages) révèle plusieurs phases de rifting du Permien au Crétacé inférieur. Un épisode majeur Jurassique supérieur à Crétacé inférieur est à l’origine de l’épaisse séquence sédimentaire du Bassin de Columbrets. Documentée à terre, cette phase ayant conduit à l’ouverture de la partie sud de l’Atlantique Nord est à l’origine de bassins ibériques ou péri-ibériques tels Maestrat, Caméros ou Parentis.Un amincissement majeur de la croûte est visible sous l’épaisse séquence mésozoïque, la réduisant à 5km. Le mécanisme d’extension voire d’hyper-extension proposé invoque une faille de détachement à pendage NW qui s’enracine dans la croûte inférieure litée. Une représentation des structures en 3D a été réalisée afin de comprendre l’évolution du Bassin de Columbrets.L’architecture sédimentaire du Bassin de Columbrets est également contrôlée par le mouvement des séries salifères depuis leur dépôt au Trias supérieur jusqu’à l’actuel. La partie septentrionale du bassin se caractérise par une halocinèse surtout lié aux déformations extensives de la région. En revanche au sud du front chevauchant des Bétiques, le sel est aussi remobilisé en compression. La géométrie et la répartition des structures salifères décrites à terre et en mer dépendent fortement de l’épaisseur initiale de la couche de sel dans le bassin; cette observation apporte des éléments de réponse sur la paléogéographie des séries du Keuper au sud du Bassin de Valence.Au final cette étude aborde d’une part des thèmes liés au mécanisme de formation des bassins intracontinentaux et plus particulièrement la relation entre hyper-extension, signature sédimentaire et halocinèse. D’autre, elle permet une meilleure intégration du sud du Promontoire Baléare et du Bassin de Valence dans la géodynamique Ouest- Méditerranéenne. / The Valencia Basin, located east of Iberia and separated from the Algerian Basin by the Balearic promontory, underwent a poly-phased tectonic evolution in space and time. The Cenozoic evolution of the basin has been widely discussed, the most classical interpretation being an Oligo-Miocene aborted back-arc basin. However, this extensional tectonic regime postdated several rifting events from the Permian to the Lower Cretaceous. This older evolution remains poorly understood offshore, despite its influence on the tectonic inheritance of the basin. The Columbrets Basin, in the southernmost part of the Valencia Basin, exhibits a thick Mesozoic sequence that was considered to belong to an undifferentiated “acoustic basement”. Hence, the Columbrets Basin is a key study area to unravel the successive Mesozoic to Cenozoic tectonic events in Eastern Iberia and Western Mediterranean.Our study integrates onshore and offshore data to better constrain (1) the Cenozoic tectonic processes that led to the current morphology of the southern Valencia Basin and the Western Mediterranean (2) the sedimentary records Mesozoic extensional to hyper-extensional processes and (3) the importance of the halokinesis in the sedimentary and tectonic architectures.Ibiza Island, located on the southernmost part of the Balearic Promontory, questions the standard tectonic agenda of the area and its integration in the Western Mediterranean geodynamic frame. The Oligo-Miocene rifting phase described in the Valencia basin is initiated by the European Cenozoic Rift System (ECRIS) and has been observed in Ibiza. This event is followed by a Middle Miocene contractional phase reactivating the inherited normal faults. The comparison with the tectonic history of the Kabylies in Algeria shows that this stage that does not affect the Algeria basin, results from the convergence between Europe and Africa. A set of retro-tectonic maps integrates these events in the geodynamic context of West Mediterranean.The Mesozoic units were studied onshore and offshore (using drilling and seismic data); it reveals several rifting phases from the Permian to the Lower Cretaceous. A major Upper Jurassic to Lower Cretaceous event was responsible for the deposition of the thick sequence present in the Columbrets Basin. This tectonic event led to the opening of the southern part of the north Atlantic but is also at the origin of several Iberian or peri-iberian basins such as Maestrat, Cameros, or Parentis basins.A major crustal thinning has been observed underneath the thick Mesozoic sequence, reducing the crustal thickness to 5 km. The proposed extensional and even hyper-extensional mechanism used a NW dipping detachment fault rooting deeply into the layered lower crust. A 3D geometrical model of the structures illustrates the evolution of the Columbrets Basin.The sedimentary architecture of this basin is also controlled by salt movements from their deposition during the Late Triassic to current times. The northern part of the Basin is characterized by salt movements mainly linked to the extensional deformations of the area. South of the Betics Front, the salt is remobilized by compressional deformations. The geometry and the location of the salt structures described onshore and offshore depend on the initial thickness of the salt in the basin; this observation gives evidence for the paleogeography of the Keuper sequences in the south of Valencia Basin.Finally, this study documents the mechanisms leading to the formation of intracontinental basins and especially the relationships between hyperextension, sedimentary filling and halokinesis. On the other hand, our study allows a better integration of the southern part of the Balearic Promontory and Valencia Basin in the geodynamic frame of the West Mediterranean.
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El comercio en el Reino de Valencia durante la primera mitad del siglo XIV: instituciones, rutas y grupos mercantiles

Soler Milla, Juan Leonardo 30 January 2015 (has links)
El comercio medieval valenciano es un ámbito de estudio que ha conocido un extraordinario auge en las dos últimas décadas, aunque centrado básicamente en el siglo XV (véanse principalmente, entre otros, los trabajos de J. Hinojosa, J. Guiral, P. Iradiel, E. Cruselles y D. Igual, de una nómina más extensa). La centuria anterior, marco temporal de nuestro proyecto de tesis doctoral, sin embargo apenas ha suscitado el interés por parte de los investigadores, con la excepción de las aproximaciones realizadas hace más de tres décadas por Guy Romestan, sobre todo en un trabajo que abarcaba únicamente la actividad de los mercaderes languedocinos en la capital del reino; y el análisis puntual de R. Ferrer sobre las "coses vedades"; productos no exportables por orden real, centrándose sobre todo en las dos últimas décadas. Es por ello que el estado actual de nuestros conocimientos acerca de la temática sea el establecido en los manuales y obras de generales de referencia, muy posiblemente imagen adaptada de otras realidades regionales peninsulares y mediterráneas. El análisis de diferentes ámbitos de política económica estructurada por la Corona y/o los munícipes de Valencia en las redes de abastecimiento y mercado, de configuración política de la costa y franja marítima y la organización económica de un espacio de nueva conquista para su dominio político, como son las tierras de la procuración/gobernación de Orihuela, comprende el Bloque I. La relación entre política y economía en el comercio bajomedieval: política económica, regulación normativa o institucionalización de los espacios mercantiles valencianos. Las redes de transporte marítimo en Valencia durante la primera mitad del siglo XIV obedece ineludiblemente al interés por proporcionar un primer y provisional balance de conjunto de las actividades marítimas de la ciudad en relación a su propio desarrollo económico interno, sus vínculos con otras ciudades que también estaban plenamente inmiscuidas en el proceso de expansión mediterránea (como las ciudades de Barcelona y Mallorca) y los intereses por abastecerse de mercancías que no se hallan en su mercado y que precisan de unas inversiones de capital, organización del transporte y estrategias económicas determinadas engloban el Bloque II: Las redes comerciales: rutas mercantiles ibéricas y mediterráneas, y contactos atlánticos desde el espacio valenciano. Asimismo, interesa profundizar en la formación de los métodos comerciales e instituciones y grupos mercantiles sobre los que se asientan las bases de una primera expansión mercantil. El tercer Bloque del estudio se vertebra en Los protagonistas humanos: instituciones-técnicas y grupos mercantiles en el espacio económico valenciano en el que se analizan las técnicas comerciales desarrolladas, incidiendo en los aspectos meramente técnicos y sociales, insertando su grado desarrollo en consonancia a otras investigaciones de la Corona de Aragón en un momento determinado, la primera mitad del siglo XIV en el que escasean los estudios de esta índole, y que, asimismo resulta difícil comparar estas instituciones y técnicas con otros espacios euromediterráneos, como los italianos, al conocer un grado de perfección, u otros ámbitos en los que apenas la historiografía ha trabajado en ello. El examen de los grupos mercantiles, precisamente a través de instituciones como sociedades/compañías comerciales de mercaderes y otros agentes valencianos, y la presentación de un caso inicial de estudio, como son los patrones de nave constituyen un primer acercamiento desde el prisma de historia social, aún por profundizar para nuestro estudio, sobre lo que se ha considerado la primera burguesía mercantil, o simplemente el origen de un grupo de mercaderes autóctonos. Finalmente este bloque se completa sobre otros grupos sociales, muy heterodoxos, esto es las minorías étnico-religiosas, mudéjares y judíos, que, además de reclamo historiográfico permanente, conviene insertar su función económica en el entramado de mercado y relaciones comerciales articuladas desde el espacio valenciano.
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[en] DEGRADATION OF PHENOL IN WATERS FOR ADVANCED OXIDATION PROCESSES USING METALLIC IRON AND HYDROGEN PEROXIDE / [pt] DEGRADAÇÃO DE FENOL EM ÁGUAS POR PROCESSO OXIDATIVO AVANÇADO UTILIZANDO FERRO METÁLICO E PERÓXIDO DE HIDROGÊNIO

NILDO DE ABREU VIEIRA JUNIOR 29 October 2021 (has links)
[pt] A crescente contaminação das águas por atividades industriais é um dos maiores problemas da sociedade moderna, pois a água é essencial para a vida e para as atividades domésticas, agrícolas e industriais. Entre os principais poluentes orgânicos encontrados em efluentes aquosos, podemos citar o fenol e seus derivados. Estes compostos são tóxicos ao homem e as espécies aquáticas, mesmo em baixas concentrações e são gerados em quantidades consideráveis em efluentes da indústria siderúrgica, de petróleo, de resinas, papel e celulose entre outras. Este trabalho teve como objetivo geral investigar, dentro das técnicas de oxidação avançada, a potencialidade do ferro metálico como catalisador no processo para a degradação do fenol em efluentes industriais, utilizando para isto lã de aço comercial. O processo foi estudado em batelada, simulando um efluente com fenol na concentração de 200mg/L, típica destas indústrias. Foram avaliadas condições de pH (5, 6, 7, 8 e 9), relação de massa de lã de aço por volume de solução (1, 2,5, 5 e 7 g/L), dosagem de peróxido de hidrogênio (1, 2 e 3 g/L) e temperatura do processo (25, 35 e 45 °C). A degradação do fenol alcançou uma eficiência de 98 porcento da concentração inicial do poluente no tempo de 120 minutos. A análise de COT (Carbono Orgânico Total) mostrou uma mineralização em torno de 33 porcento. Assim, o uso de ferro metálico como catalisador na degradação oxidante de fenol em águas apresenta-se como uma alternativa viável, devido a sua eficiência e simplicidade operacional. / [en] The increasing contamination of water by industrial activities is one of the biggest problems of modern society, because water is essential for life and for domestic activities, agriculture and industry. Among the major organic pollutants found in aqueous solution can be mentioned phenol and its derivatives. These compounds are toxic to humans and aquatic species, even at low concentrations and are produced in considerable quantities in effluent of the steel industry, oil, resins, pulp and paper among others. This study aimed to investigate, within the techniques of advanced oxidation, the potential of metallic iron as a catalyst in the process for the degradation of phenol in industrial waste, using it for steel wool. The batch process was studied, simulating an effluent phenol concentration of 200mg / L, typical of these industries. We evaluated the pH conditions (5, 6, 7, 8 and 9), mass of steel wool (1, 2.5, 5 and 7 g), mass of hydrogen peroxide (1, 2 and 3g) and process temperature (25, 35 and 45 ° C). Analyses of the degradation of phenol, made by a spectrophotometer, with a specific methodology for this analysis showed a reduction of 98 percent of the initial concentration of pollutant at time of 120 minutes. The analysis of TOC (Total Organic Carbon) showed a mineralization of about 33 percent, as reported in the literature for this type of process. Thus, the use of metallic iron as a catalyst in water treatment and effluent is presented as a viable alternative in the degradation of this pollutant, due to its efficiency, in addition to low cost and operational simplicity.

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