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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.
321

里山からキツネが消えた日 : 豊田市小手沢町の地蔵堂から見つかったキツネの遺骸

Ikeda, Akiko, Minami, Masayo, Nakamura, Toshio, Suzuki, Kazuhiro, 池田, 晃子, 南, 雅代, 中村, 俊夫, 鈴木, 和博 03 1900 (has links)
第23回名古屋大学年代測定総合研究センターシンポジウム平成22(2010)年度報告
322

Halogénation et propriétés structurales et supraconductrices des oxydes La2-xBaxCuO4 (phases de type T) et La1,8-xSmxSr0,2CuO4 (phases de type T, T* ou T')

Ben Salem, Ezzedine 20 December 1994 (has links) (PDF)
L'étude de l'influence de traitements d'halogenation sur les propriétés structurales et supraconductrices des cuprates de structure de type T,T' ou T* a permis de mettre en évidence: la restauration après fluoration de la supraconductivite dans le cas de l'oxyde La1,875Ba0,125CuO4 de structure de type T. Celle-ci s'accompagne de la modification de la transition structurale orthorhombique (MTO) quadratique (LTT) ; l'apparition d' un comportement supraconducteur après traitement sous chlore de l' oxyde LaSm0,8Sr0,2CuO4 de structure de type T*. La fluoration de cet oxyde conduit a la formation de deux phases isotypes. Leurs propriétés structurales et supraconductrices ont été étudiées a l'aide de diverses techniques: diffraction X et neutronique, EXAFS, susceptibilité magnétique, conductivité électrique et thermique, pouvoir thermoelectrique...
323

Impact of SR-BI and CD81 on Hepatitis C virus entry and evasion

Zahid, Muhammad Nauman 27 April 2012 (has links) (PDF)
Hepatitis C virus (HCV) is a major cause of liver cirrhosis and hepatocellular carcinoma. In the first part of my PhD, we aimed to further characterize the role of scavenger receptor class B type I (SR-BI) in HCV infection. While the SR-BI determinants involved in HCV binding have been partially characterized, the post-binding function of SR-BI remains remained largely unknown. To further explore the role of HCV-SR-BI interaction during HCV infection, we generated a novel class of anti-SR-BI monoclonal antibodies inhibiting HCV infection. We demonstrated that human SR-BI plays a dual role in the HCV entry process during both binding and post-binding steps. Targeting the post-binding function of SR-BI thus represents an interesting antiviral strategy against HCV infection. In the second part of my PhD, we aimed to characterize the molecular mechanisms underlying HCV re-infection of the graft after liver transplantation (LT). We identified threeadaptive mutations in envelope glycoprotein E2 mediating enhanced entry and evasion of a highly infectious escape variant. These mutations markedly modulated CD81 receptor dependency resulting in enhanced viral entry. The identification of these mechanisms advances our understanding of the pathogenesis of HCV infection and paves the way for the development of novel antiviral strategies and vaccines.
324

Ceux qui "font" le journal : journalistes secrétaires de rédaction et ouvriers typographes à l'interface de la matérialité de l'information en presse quotidienne régionale / The newspaper “makers” : sub-editors and typographers at the of crossroads of information materiality in regional daily press

Langonné, Joël 14 December 2016 (has links)
Cette recherche pose une question simple : Qui fait quoi dans le journal ? Nous y répondons partiellement en nous focalisant sur un domaine spécifique du continuum de fabrication de l’information : le prépresse. Il s’agit du moment où l’information fournie par les journalistes rédacteurs est matérialisée, dessinée par les journalistes secrétaires de rédaction (SR) dans les pages du quotidien. Cet espace nous permet de mettre en avant un collectif singulier dans le journal. Car jusqu’à la fin des années 1990 et la numérisation totale de la chaine de fabrication des quotidiens, les SR ne sont pas seuls responsables du prépresse, ils coopèrent quotidiennement avec des ouvriers : les typographes. Ainsi, SR et typographes « font » le journal ensemble. Or, nous considérons que ces gens sont à ce qu’ils font de manière distincte, et par conséquent nous nous attachons à décrire qui fait quoi comment. C’est-à-dire que nous observons ce qui est à faire – le journal – en étant attentif à la manière dont journalistes et ouvriers se lient ou non pour y parvenir. Cette étude de qui fait quoi comment dans le journal se décline en trois temps. Nous tentons tout d’abord de comprendre De quoi est fait le monde des typographes (1) : Quels sont leurs appuis pour composer leur goût pour être à ce qu’ils font ? Dans quoi peuvent-ils puiser pour être typographes comme ils l’entendent ? Nous nous demandons ensuite, de la même manière, De quoi est fait le monde des SR (2) ? Quel est l’équipement des SR pour composer leur monde ? Dans quels scripts peuvent-ils puiser pour être SR au mieux des possibles ? Ce parallèle entre ces journalistes particuliers et ces ouvriers pas comme les autres nous amène à élaborer le troisième volet de ce travail : SR et typographes composent-ils un monde commun (3) ? Il s’agit de déterminer si les frottements continus de ces deux manières d’être au monde partagent certains attachements. Nous présentons quelques exemples qui suggèrent qu’un monde commun a pu exister à certaines époques et de manière non linéaire, entre SR et typographes. À partir de notre terrain, nous débusquons des parcelles de ce monde commun grâce à un médiateur spécifique : la maquette du journal.Finalement, en décrivant qui fait quoi comment dans le journal via ce qui se passe à l’interface de sa matérialité, nous découvrons un objet collectif travaillé par un grand nombre de gens et de choses. Chaque jour, le journal est suffisamment flexible pour que s’y expriment différentes présences au monde, et suffisamment solide pour (con)tenir l’expression de son énonciation collective. / To the simple question Who does what in a newspaper? this study – partially – answers by focusing on a particular aspect of the continuum of information production: the prepress – where the information provided by journalists is laid out and designed by sub-editors. This approach enables us to shed light on a unique collective of the newspaper. Indeed, until the end of the 90’s and the generalization of digitalization in the production lines of daily newspapers, sub-editors share their responsibilities and collaborate on a daily basis with a particular type of blue-collar workers: the typographers. In our opinion, sub-editors and typographers make the newspaper together, and in their own respective ways. How? What is there to do to make a newspaper, and how do – or don’t – journalists and blue-collars bind themselves to achieve their common goal?Our analysis of Who does what and how in a newspaper is divided into three parts. In a first part we describe The world of typographers (1). What supports do they lean on to work with their taste? What resources do they draw on to display their skills? In a similar way, in a second part we analyze The world of sub-editors (2). What is it made out of? What scripts do sub-editors turn to to perform at their best? A third part is dedicated to establishing parallels between these two distinctive worlds, wondering Do sub-editors and typographers form a common world (3)? Do these two ever-connected worlds share common bonds? The examples we present suggest that common worlds have existed at certain times and in non-linear ways. Our fieldwork provides us with fragments of this common world within a specific mediator: the layout.The description of who does what and how in a newspaper via what takes place at the crossroads of its material form enables us to reveal a collective object elaborated by a number of different people and things. Every day, newspapers are flexible enough to allow different perceptions to express themselves, and rigid enough to carry a collective formulation.
325

Crystallographic and microstructural study of as-cast and heat-treated Srmodified Al-12.7Si alloys / Étude cristallographique et microstructurale d'alliages Al-12.7Si modifiés au Sr bruts de coulée et traités thermiquement

Liu, Xiaorui 29 July 2016 (has links)
Les alliages aluminium-silicium (Al-Si) ont attiré une attention considérable en raison de leur importance pour les applications industrielles. Dans le présent travail, des alliages à haute pureté (Al-12.7 wt. % Si) avec et sans ajout de strontium (400 ppm), solidifiés lentement en creuset ou de façon dirigée (DS), ont été préparés et traités thermiquement. L'influence de l'ajout de strontium et des post-traitements thermiques sur les caractéristiques microstructuraux et cristallographiques des phases eutectiques a été étudiée de façon systématique. Les caractéristiques de croissance du silicium eutectique (Si) dans l'alliage non modifié ainsi que dans l'Al-12.7Si Sr-modifié ont été étudiés. Pour le cas du non-modifié, la formation répétée de variantes de macles mono-orientées permet une croissance rapide du silicium eutectique selon le mécanisme twin plane re-entrant (TPRE). Microscopiquement, les cristaux de silicium ont une forme de plaque allongée dans la direction <1 1 0> non conforme à la croissance selon <1 1 2> présumée par le modèle TPRE. L'élongation selon <1 1 0> est réalisée par des paires en zigzag <1 1 2> sur des plans de maclage parallèles, conduisant à une disparition alternative et à la création de macles rentrantes à 141°. Ce mécanisme de croissance permet aux cristaux de silicium de n'exposer que les plans {1 1 1} à faible consommation d'énergie à la consolidation. Pour les alliages modifiés au strontium, des changements importants de morphologie apparaissent dans le silicium eutectique, attribuable à la croissance de TPRE restreinte et au maclage induit par les impuretés (IIT). Ce dernier améliore la croissance latérale en formant de nouvelles macles avec des plans de macles parallèles, tandis que le second conduit à une croissance isotrope en formant des macles orientées différemment. Le traitement thermique provoque l'affinement des grains des deux phases eutectiques. L'affinement de l'α-Al se produit en même temps que la fragmentation et la sphéroïdisation du silicium et est principalement lié à la fracture des grains de silicium en raison de leur capacité limitée à accommoder la très grande dilatation thermique l'α-Al, ainsi qu'à la diffusion des atomes d'aluminium au cours du traitement thermique. La rupture du silicium génère une force de "capillarité" qui active la diffusion d'atomes d'aluminium dans la fissure. En raison du caractère de substitution de la diffusion de l'aluminium, la migration des lacunes vers l'intérieur de l'α-Al est induite lorsque l'aluminium se déplace dans les fissures, ainsi les vides de la fracture du silicium sont transférés à l'α-Al. De cette façon, les cristaux d'α-Al sont altérés et déformés. Les défauts cristallins produits, à leur tour, initient la restauration et même la recristallisation du α-Al, ce qui entraîne une diminution de taille de grain. La phase α-Al dans l'alliage de Al-12.7Si-0.04Sr solidifiée directionnellement, affiche une forte texture de fibre <1 0 0> parallèle à la direction de solidification. De très gros grains <1 0 0> α-Al sont principalement formés à la périphérie de l'échantillon cylindrique en raison des directions d'évacuation de chaleur favorables disponibles pour les trois directions [1 0 0]. Après traitement thermique, l'intensité de la texture de la phase α-Al diminue en raison de la restauration et de la recristallisation, mais le type de texture ne change pas. Pour la phase de silicium eutectique dans l'alliage de coulée, il y a deux fibres principales de texture, <1 0 0> et <1 1 0> parallèles à la direction de solidification, accompagnées de deux composantes faibles, <2 2 1> et <1 1 3> dans la même direction. Les fibres <1 0 0> et <1 1 0> correspondent à des grains de silicium situés sur la périphérie et dans le centre de l'échantillon. Les composantes <2 2 1> et <1 1 3> proviennent de plusieurs macles de grains orientés <1 1 0> et <1 0 0>. Les faibles intensités de ces deux composantes sont liées à leur fraction volumique mineure [...] / Al-Si alloys have attracted considerable attention due to their importance to industrial applications. In the present work, both crucible slowly solidified and slowly directionally solidified (DS) high-purity Al-12.7 wt. % Si alloys with and without 400 ppm Sr addition have been prepared and heat treated. The influence of Sr addition and post heat treatments on the microstructural and crystallographic features of the eutectic phases has been systematically studied. The growth characteristics of eutectic Si in the unmodified and the Sr-modified Al-12.7Si alloys were investigated. For the non-modification case, the formation of repeated single-orientation twin variants enables rapid growth of eutectic Si according to the twin plane re-entrant (TPRE) mechanism. Microscopically, Si crystals are plate-like elongated in one <1 1 0> direction that is not in accordance with the <1 1 2> growth assumed by the TPRE model. The <1 1 0> extension is realized by paired <1 1 2> zigzag growth on parallel twinning planes, leading to alternative disappearance and creation of 141° re-entrants. This growth manner ensures Si crystals to expose only their low-energy {1 1 1} planes to the melt. For the Sr-modification case, substantial changes appear in eutectic Si morphology, attributable to the restricted TPRE growth and the impurity induced twinning (IIT) growth. The first enhances lateral growth by forming new twins with parallel twinning planes, while the second leads to isotropic growth by forming differently oriented twins. Heat treatment brings about refinement of both eutectic phases. The refinement of the α-Al occurs concomitantly with the fragmentation and spheroidization of Si and is mainly related to the fracture of the Si crystals due to their limited capacity to accommodate the giant thermal expansion of the α-Al and the diffusion of Al atoms to the cracks during the heat treatment. The Si fracture generates “capillarity” force that activates the diffusion of Al atoms to the gap of the crack. Due to the substitutional feature of Al diffusion, the migration of vacancies toward the interior of the α-Al is induced when Al moves to the gaps, thus the voids of the Si fracture are transferred to the α-Al. In this way, the crystals of α-Al are distorted and defected. The produced crystal defects, in turn, initiate recovery and even recrystallization of the α-Al, resulting in grain refinement. The α-Al phase in the directionally solidified Al-12.7Si-0.04Sr alloy, displays a strong <1 0 0> fiber texture in the solidification direction. Giant <1 0 0> α-Al grains are mainly formed in the outer circle region of the cylindrical specimen due to the favorable heat evacuation directions available for the three <1 0 0> directions. After heat treatment, the texture intensity of the α-Al phase decreases due to the recovery and recrystallization, but the texture type does not change. For the eutectic Si phase in the as-cast alloy, there are two main fiber texture components, <1 0 0> and <1 1 0> in the DS direction, accompanied by two weak components, <2 2 1> and <1 1 3> in the same direction. The <1 0 0> and <1 1 0> components are from Si crystals located in the outer circle and center regions of the cylindrical specimen. The <2 2 1> and the <1 1 3> components are from multiple twins of the <1 1 0> and <1 0 0> oriented crystals. The weak intensities of these two components are related to their minor volume fraction. Once heat treated, the twinned parts with minor volume fractions enlarge at the expense of their twin related matrix, thus the <1 1 0> component is weakened and accompanied by the intensification of the components from the twins. The disappearance of the <1 1 3> component and the appearance of the <1 1 5> component are due to crystallographic rotation of Si crystals during their fragmentation
326

Analysis of small business social responsibility practices in South Africa

Masarira, Spiwe Kursawa 06 1900 (has links)
Social responsibility (SR) is a business management concept that originated in the early 1930s after the Wall Street crash of 1929 exposed corporate irresponsibility in large organizations. Whilst the initial interpretation of SR has been modified and refined since it was first used, the significance of this multidimensional concept for the small and medium enterprise (SME) sector has continued to be overshadowed by its application to large and multinational organizations. The knowledge of social activities in the SME sector, particularly in South Africa, has remained unexplored due to relatively little attention being given until recent years. In cognizance of the above mentioned, this study wishes to expand the body of knowledge in respect of the social responsibility of small businesses. This study presented a qualitative content analysis of annual reports from 2008 to 2012 of companies listed on the JSE ALT exchange to explore small business social responsibility practices using NVIVO to analyze data. Findings from this study support the view that small businesses are not always profit driven and that they are therefore fundamentally distinct from large organizations. South African small businesses are however not yet strategic about SR. Creating and maintaining their reputation as good corporate citizens through relationships with stakeholders is their primary motivation for participating in social activities. The study results show that SR in small businesses is still evolving and that year after year there is an increase in involvement and interest in SR issues. The findings of this study, and confirmation of the new knowledge gained will assist policy makers and practitioners in designing plans and policies that will increase socially responsible behaviour of small businesses and develop a comprehensive theory of SR in small businesses in South Africa. This can potentially enhance inclusive economic growth while simultaneously dealing with the country’s socio economic problems. Future studies can be extended to include other SMEs in South Africa, specifically micro enterprises and comparisons formed by a larger population may demonstrate and explain trends more clearly. The results of this study can also be compared with large companies listed on the JSE and to other African economies. A longitudinal study investigating SMEs’ participation in SR in different economic conditions could test the fact that a change has occurred in the attitudes of small businesses from 2008 to 2012 towards social responsibility / Business Management / D.B.L
327

Estudo geoqu?mico e geocronol?gico Rb-Sr e Sm-Nd em zonas de cisalhamento mineralizadas em ouro e suas rela??es com as rochas encaixantes e geocronol?gico Sm-Nd em mineraliza??es de scheelita na faixa Serid?

Trindade, Ivaldo Rodrigues da 31 May 2000 (has links)
Made available in DSpace on 2015-03-13T17:08:17Z (GMT). No. of bitstreams: 1 IvaldoRT.pdf: 3649445 bytes, checksum: 624c427ba32cfc36890765f50db5140c (MD5) Previous issue date: 2000-05-31 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / Great part of the gold mineralizations are associated with shearing zones through which circulate a great volume of fluids, that interact with the host rocks, originating leaching or precipitation of chemical elements, including gold. The studied mineralizations are inserted in the Serid? Belt. The tungsten mineralization in Breju? Mine is hosted in calcsilicate rocks from Jucurutu Formation. The S?o Francisco auriferous mineralization has as host rocks mica-schists from Serid? Formation, while the Ponta da Serra and Fazenda Simp?tico mineralizations are hosted in orthogneisses of this fold belt basement. The research conducted on these mineralizations had the purpose of integrate the data of chemical elements behavior during the shearing/mineralizing event, and its influence on the isotopic systems Rb-Sr and Sm-Nd. The studies of chemical mobility in the auriferous mineralizations showed that elements that during the shearing displayed in general an immobile behavior were Al, Ti and Zr. Among the elements that were mobilized during the event, K and Rb showed mass gain in ali belts of transformed rocks, while the elements Ca, Na and Sr normally lost mass. Petrographic studies showed that the minerais biotite and plagioclase, in all investigated mineralizations, played an important role in the chemical reactions occurred in the transformed rocks to the generation of muscovite, cordierite and sillimanite, justifying the input of K to the formation of muscovite, and the release of Na and Ca from plagioclase to the fluid phase. In the S?o Francisco auriferous mineralization, the results of the Rb-Sr isotopic analysis yielded ages of 645 ? 19 Ma and 596 ? 17 Ma, with both samples, from original and transformed rocks. Two ages, 569 ? 20 Ma. and 554 ? 19 Ma., were obtained with samples frem the transformed rocks domain. These ages suggest that there were two metamorphic pulses during the emplacement of the mineralized shearing zone. The Sm-Nd data yielded TDM ages of 1,31 Ga and 1,26 Ga with 3Nd (0,6 Ga) of -0,26 e -0,40 for the original and final transformed rocks, respectively. In case of the orthogneisses of Caic? Complex, e.g. the Ponta da Serra and Fazenda Simp?tico mineralizations, the Rb-Sr data did not yield ages with geological significance. In the Ponta da Serra mineralization, the Sm-Nd isotopic data yielded T DM ages of 2,56 Ga and 2,63 Ga to the original rocks and of 2,71 Ga to the mineralized sheared rock, and values of 3Nd (2,0 Ga) between -3,70 e -5,42 to the original and sheared rock, respectively. In the Fazenda Simp?tico, Sm-Nd data yielded TDM between 2,65 and 2,69 Ga with values of 3Nd (2,0 Ga) between -5,25 e -5,52. Considering the Sm-Nd data, the TDM ages may be admitted as the age of the parental magma extraction, producer of the protoliths of the orthogneisses from Ponta da Serra and Fazenda Simp?tico mineralizations. The chemical mobility studies showed that in the basement hosted mineralizations, Rb achieved mass while Sr lost mass, as Sm as well as Nd were strongly mobilized. The Sm/Nd ratio remained constant, however, confirming the isochemical character of those elements. In the basement mineralizations, Rb-Sr ages are destituted of geological significance, because of the partial opening of the isotopic system during the tectono-metamorphic transformations. In the tungsten mineralization, the diagram Sm-Nd constructed with the whole-rock data of calcsilicatic and the high-temperature paragenesis (garnet, diopside and iron-pargasitic hornblende) indicated an 631 ? 24 Ma age, while with the whole-rock data and low-temperature paragenesis (vesuvianite, epidote and calcite), a 537 ? 107 Ma age was obtained. These ages, associated with the petrographic observations, suggest that there was a time gap among the hydrothernal events responsible by the formation of the high and low temperature paragenesis in the calcsilicatic rocks mineralized in scheelite / As mineraliza??es estudadas est?o inseridas na Faixa de dobramento Serid?. A scheelit?fera de Breju? est? hospedada em rochas calciossilic?ticas da Forma??o Jucurutu. A mineraliza??o aur?fera de S?o Francisco tem como hospedeiros micaxistos da Forma??o Serid?, enquanto que as mineraliza??es de Ponta da Serra e da Fazenda Simp?tico est?o hospedadas em ortognaisses do embasamento desta faixa de dobramentos. Grande parte das mineraliza??es de ouro est?o associadas ? zonas de cisalhamento que funcionam como conduto para a circula??o de um grande volume de fluidos, que interagem com as rochas hospedeiras provocando lixivia??o ou precipita??o de elementos qu?micos, incluindo o ouro. Estas foram algumas das principais caracter?sticas observadas nas mineraliza??es aqui estudadas. A pesquisa realizada nas mineraliza??es de ouro teve a finalidade de integrar os dados do comportamento de elementos qu?micos durante o evento cisalhamento/mineralizante, e sua influ?ncia nos sistemas isot?picos Rb-Sr e Sm-Nd. Os estudos de mobilidade qu?mica mostraram que os elementos, que durante o cisalhamento, de uma forma geral apresentaram um coportamento im?vel, foram o AI, Ti e Zr. Dentre os elementos que foram mobilizados durante o evento, o K e o Rb mostraram ganho de massa em todas as faixas de rochas transformadas, enquanto que os elementos Ca, Na e o Sr normalmente perderam massa. Os elementos Sm e Nd na mineraliza??o de S?o Francisco se comportaram como im?veis e em Ponta da Serra e Fazenda Simp?tico perderam massa. Os estudos petrogr?ficos mostraram que os minerais biotita e plagiocl?sio, em todas as mineraliza??es estudadas, tiveram papel importante nas rea??es qu?mica ocorridas nas rochas transformadas para a gera??o de muscovita, cordierita e silimanita, justificando a entrada do K para forma??o da muscovita e da libera??o de Na e Ca do plagiocl?sio para a fase fluida. Na mineraliza??o aur?fera de S?o Francisco, os resultados das an?lises isot?picas de Rb e Sr, forneceram idades de 645 ? 19 Ma e de 596 ? 17 Ma com amostras das rochas originais e transformadas juntas. Duas idades, 569 ? 20 Ma e 554 ? 19 Ma foram obtidas com as amostras do dom?nio das rochas transformadas. Estas idades s?o sugestivas de que houve dois pulsos metam?rficos durante a instala??o da zona de cisalhamento mineralizada. Os dados Sm-Nd forneceram idades TDM de 1,31 Ga e de 1,26 Ga com 3Nd (0,6 Ga) de -0,26 e -0,40 respectivamente para a rocha original e transformada final. Para os ortognaisses do Complexo Caic?, caso da mineraliza??o de Ponta da Serra e da Fazenda Simp?tico, os dados Rb-Sr n?o forneceram idades com significado geol?gico. Na mineraliza??o de Ponta da Serra, os dados isot?picos Sm-Nd forneceram idades T DM de 2,56 Ga e 2,63 Ga para as rochas originais e de 2,71 Ga para a rocha cisalhada, mineral?zada e valores de 3Nd (2,0 Ga) entre -3,70 e -5,42 para rocha original e cisalhada respectivamente. Na Fazenda Simp?tico os dados de Sm-Nd forneceram as idades T DM ficaram entre 2,65 e 2,69 Ga com valores de 3Nd (2,0 Ga) entre -5,25 e -5,52. Quanto aos dados Sm-Nd as idades T DM podem ser admitidas como a idade de extra??o do magma parental formador dos prot?l?tos dos ortognaisses das mineraliza??es Ponta da Serra e da Fazenda Simp?tico. Os valores de 3Nd baixos e negativos sugerem uma fonte crustal, ou a participa??o de duas fontes (mantocrosta) . Os estudos de mobilidade qu?mica mostraram que nas mineraliza??es hospedadas no embasamento, o Rb ganhou massa enquanto o Sr perdeu massa e tanto o Sm quanto o Nd, foram fortemente mobilizados. As raz?es Sm/Nd entretanto se mantiveram constantes, confirmando o car?ter isoqu?mico destes elementos. Nas mineraliza??es do embasamento, idades pelo m?todo Rb-Sr s?o desprovidas de significado geol?gico, em fun??o da abertura parcial do sistema isot?pico durante as transforma??es tectonometam?rficas. Na mineraliza??o scheelit?fera foi realizado um estudo geocronol?gico Sm-Nd com o intuito de se obter as idades das parag?neses formadas durante os eventos hidrotermais sofridos pelas rochas calciossilic?ticas mineralizadas. O diagrama Sm-Nd constru?do com os dados de rocha total e parag?nese de alta temperatura (granada, diops?dio e hornblenda ferropargas?tica) forneceu uma idade de 631 ? 24 Ma, e com os dados de rocha total e parag?nese de baixa temperatura (vesuvianita, epidoto e calcita), foi obtida uma idade de 537 ? 107 Ma. Estas idades associadas com as observa??es petrogr?ficas sugerem que houve um lapso de tempo entre os eventos hidrotermais respons?veis pelas forma??es das parag?neses de alta e de baixa temperatura nas rochas calciossilic?ticas mineralizadas em scheelita
328

Avaliação da agua e do sedimento das microbacias dos Ribeirões Graminha e Aguas da Serra na cidade de Limeira, SP / Evaluation of the water and the sediment of the microbasins of Brooks Graminha and Aguas da Serra in the city of Limeira, SP

Fazza, Elizete Vieira 29 August 2007 (has links)
Orientador: Silvana Moreira / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Civil, Arquitetura e Urbanismo / Made available in DSpace on 2018-08-11T03:52:29Z (GMT). No. of bitstreams: 1 Fazza_ElizeteVieira_M.pdf: 2172063 bytes, checksum: 9efe3c01da1dbb554288a537bfa44ea7 (MD5) Previous issue date: 2007 / Resumo: A cidade de Limeira está localizada no Estado de São Paulo e possui economia expressiva, com indústrias em vários setores produtivos, entre elas, galvanoplastias voltadas para a produção de jóias, semijóias e bijuterias. Visando elucidar se há influência antropogênica nos mananciais da cidade, avaliou-se a qualidade das águas e as concentrações de metais presentes na água e nos sedimentos dos ribeirões Graminha e Águas da Serra, cujas nascentes estão na zona urbana de Limeira. As determinações de metais foram realizadas pela técnica de Fluorescência de Raios X por Reflexão Total com Radiação Síncrotron (SR-TXRF). Os limites de detecção para amostras de água estão na faixa de 0,50 a 0,05 µg.L-1 para Ca e Zn, respectivamente, enquanto que para as amostras de sedimento os limites de detecção obtidos foram iguais a 0,22 e 0,02 µg.g-1 para os mesmos elementos. Nas amostras de água dos dois mananciais e para ambos os períodos amostrados (seco e húmido) as concetrações de Al e Fe foram superiores aos limites máximos permissíveis estabelecidos pela legislação vigente. Os elementos Zn e Cu apresentaram o mesmo comportamento. Para o Cr e Ni apenas alguns pontos de amostragem apresentaram valores acima dos limites permitidos. No ribeirão Águas da Serra os valores foram superiores ao permitido para todos os pontos exceto pra dois pontos no período seco, enquanto que para o ribeirão Graminha os resultados foram superiores para quatro pontos no período úmido. Nas amostras de sedimento o elemento Cu ultrapassou o valor estabelecido pela legislação em ambos os mananciais. Os valores para Pb nas amostras de sedimento também foram ultrapassados para todas as amostras do ribeirão Águas da Serra e em alguns pontos do Graminha. Os resultados obtidos para Cr foram excedidos em três pontos no período húmido e em dois pontos no período seco para o ribeirão Águas da Serra, e no Graminha apenas no período seco os valores para dois pontos foram excedidos. Para Ni e Zn em apenas alguns pontos foram observados valores acima do permitido. A metodologia aplicada foi eficiente porque permitiu a determinação dos metais a níveis exigidos pela legislação brasileira. As concentrações dos metais foram superiores aos valores máximos permissíveis estabelecidos pela legislação vigente para vários elementos tanto nas amostras de água quanto nas amostras de sedimento. Os resultados apontam para a necessidade de ações para recuperar a qualidade dos mananciais bem como protegê-los de novas alterações antrópicas negativas. Palavras Chave: Metais pesado, Água ¿ Qualidade, Sedimentos, Poluição -- Aspectos Ambientais, Meio ambiente, Fluorescência de raio X, Síncrotron / Abstract: The city of Limeira is located in the State of São Paulo and has expressive economy, with industries in several productive sectors, as galvanization industries for the jewels, semi-jewels and bijoux production. Aiming to explain the anthropogenic influence in the sources, the water and sediment qualities of the Graminha and Águas da Serra brooks were evaluated whose springs are in the urban zone of Limeira. The metal determination was performed using Synchrotron Radiation Total Reflection X-Ray Fluorescence (SRTXRF). The detection limits for water samples were in the range of 0.50 to 0.05 µg.L-1 for Ca and Zn, respectively while for sediment samples the detection limits were 0.22 to 0.02 µg.g-1 for the same elements. For water samples in both brooks and for all periods (dry and humid) the concentrations of Al and Fe were higher than the maximum permissive values (MPV) established by the legislation. For Zn and Cu the same behaviour was observed. For Cr and Ni just some locations presented values higher than MPV for water samples. Moreover in Águas da Serra brook values higher than MPV were observed for all points except for two points in the dry period, for Graminha 12 stream the results were higher for four sample locations in the humid period. For sediment samples Cu surpass the value established by the legislation for both springs. For Pb the values surpass the limit for all samples in Águas da Serra and some points for Graminha stream. The results for Cr in sediment samples were surpassed for three points in the humid period and two points in the dry period for Águas da Serra brook, and in Graminha just in the dry period for two points the values were exceeded. For Ni and Zn only a few points surpassed the limits for both springs.The applied methodology was efficient because the detection limits turned possible the determination of the metals in levels in according to legislation. The metal concentrations were higher than the maximum permisse values established by the Brazilian Legislation for several elements in water and sediment samples. The results point to the action necessity to recover the quality of the sources as well as to protect the brooks of new negative anthropogenic alterations. Keywords: Heavy metals, Water quality, Sediment, Pollution, Environment, Synchrotron Radiation Total Reflection X-Ray Fluorescence (SR-TXRF) / Mestrado / Saneamento e Ambiente / Mestre em Engenharia Civil
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Análisis del uso de dispositivos móviles en el desarrollo de estrategias de mejora de las habilidades espaciales

Martín Dorta, Norena Natalia 30 September 2011 (has links)
Las nuevas interfaces de usuario y los recientes desarrollos en el campo de las comunicaciones móviles han creado un amplio abanico de posibilidades para los usuarios y para el diseño y el acceso a los materiales de aprendizaje. Esta tesis explora las oportunidades que nos ofrecen las nuevas interfaces usuario y la utilización de dispositivos móviles de pantalla táctil, con la intención de ofrecer cursos intensivos de mejora de las habilidades espaciales a los estudiantes de ingeniería con mayores dificultades en este ámbito. Con este propósito y en este contexto se abordan: -Nuevas herramientas y nuevos formatos: SketchUp y los dispositivos móviles de pantalla táctil, -Nuevos contextos: la educación a distancia y -Medida de la satisfacción de los usuarios: evaluación de los cursos realizados. Con este objetivo, este trabajo se estructura en base a dos líneas de actuación, diferenciadas en función del soporte utilizado y conectadas por su desarrollo temporal: 1. Se desarrollan dos estudios de campo con estudiantes de primer curso de ingeniería, un primer estudio utilizando el software SketchUp y otro con una aplicación web interactiva denominada "Building with blocks". Estos dos trabajos se muestran efectivos en la mejora de las habilidades espaciales. 2. Los resultados obtenidos nos permiten abordar el diseño de nuevos materiales sobre dispositivos móviles de pantalla táctil. Se elaboran dos tipologías: -Un entorno web interactivo en formato plano (2D), optimizado para dispositivos tipo iPod Touch. Se diseña y evalúa un curso on-line programado para cinco días con este material. El curso muestra su efectividad en la mejora de las habilidades espaciales y es valorado con un alto grado de satisfacción por los estudiantes. -Una aplicación para teléfonos móviles de pantalla táctil que nos permite la construcción de modelos de cubos en un entorno tridimensional y que ha sido desarrollada para el sistema operativo Windows Mobile. / Martín Dorta, NN. (2009). Análisis del uso de dispositivos móviles en el desarrollo de estrategias de mejora de las habilidades espaciales [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/11796 / Palancia
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Systémique Relativisée : essences des conceptualisations relativisées du Réel / Relativized systemic : roots of any relativized conceptualization of Reality

Boulouet, Henri 03 October 2014 (has links)
La notion de ‘système’ est omni présente dans nos conceptualisations du Réel et dans l’élaboration de nos projets. L’incapacité de lui conférer pourtant une définition généralement et scientifiquement acceptable questionne les traits les plus profonds de la conceptualisation classique, ceux qui fondent les langages courants, les grammaires et la logique classique. Ces traits sont rigidement liés à la croyance que ce que nous connaissons est ce qui existe ‘vraiment’, tel que nous le connaissons. Or cette croyance est démentie par la microphysique où il apparaît que nous engendrons nos connaissances de fond en comble, aussi bien les ‘entités’ que nous examinons, que les qualifications de celles-ci. La Méthode de Conceptualisation Relativisée (MCR) de M. Mugur-Schächter établit que ces processus d’engendrement sont soumis à des relativisations dont l’explicitation précise les significations et permet de maîtriser les finalités. Il est frappant de percevoir à quel point MCR dissout les ambiguïtés intrinsèques à la notion de système. Mais cette mise au clair implique au préalable la mise en évidence des relativisations qui agissent dans la genèse conceptuelle-factuelle des notions fondamentales de persistance, de continuité, d’état et de causalité. Elle entraine la redéfinition relativisée des concepts de loi de probabilité, d’entropie et de complexité. Le résultat est dénommé Systémique Relativisée (SR). Il possède le caractère d’un infra-cadre méthodologique au développement de méthodes technico-scientifiques spécifiquement adéquates à des domaines d’application particuliers, telle l’Ingénierie Système Relativisée, appliquée à la conception d’artefacts à buts utilitaires. / The idea of ‘system’ is pervasive in our descriptions and in our projects. The impossibility to come up with a generally and scientifically valid definition of this idea touches the most profound features of the classical conceptualization, those that underlie the current languages, the grammars and the classical logic. These features are rigidly tied with the belief that what we know is what ‘really’ exists, such as we know it. But this belief is refuted by microphysics, where it appears that that we create our knowledge entirely, as much the ‘entities’ that we examine as the qualifications of these entities. The Method of Relativized Conceptualisation of M. Mugur-Schächter establishes that the processes of creation of knowledge are subjected to relativizations, and that making them explicit clarifies the involved significances and permit to dominate the finalities. It is surprising to perceive to what a point the relativizations required by the method winds up the ambiguities commonly tied up to the idea of system. But such a clarification requires first to bring into light the relativizations acting in the conceptual-factual genesis of such basic concepts as persistence, continuity, state or causality. It brings about the relativized redefinitions of the concepts oflaw of probability, of entropy and of complexity. The global result is called Relativised Systemic (RS). It possesses the character of a methodological infra-frame for the design of technical-scientific constructivist methods, specifically appropriate for particular domains of application, such as the Relativised System Engineering method (RSE), dedicated to the design of utilitarian artefacts.

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