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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.
201

Monitoramento da concentração e caracterização do material particulado suspenso na atmosfera

Amorim, Wanda Batista de 07 August 2004 (has links)
Orientador: Meuris Gurgel Carlos da Silva, Edson Tomaz / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Quimica / Made available in DSpace on 2018-08-04T00:13:51Z (GMT). No. of bitstreams: 1 Amorim_WandaBatistade_D.pdf: 8307667 bytes, checksum: 77ad4f9967c1243056a9d1693c25d495 (MD5) Previous issue date: 2004 / Resumo: O município de Paulínia, localizado a 110 km de São Paulo e com uma população em tomo de 51.000 habitantes, possui um parque industrial expressivo e complexo que emite diariamente grandes quantidades de poluentes na atmosfera, alterando a qualidade do ar da região. Dentre estes poluentes destaca-se o material particulado inaláveI (partículas menores do que 10 J.lm, MPJO), que se constitui em partículas que penetram no sistema respiratório e podem atingir os alvéolos pulmonares levando a sérios danos à saúde. Neste trabalho, foi realizado o monitoramento e caracterização do MP1O presente na atmosfera do bairro João Aranha em Paulínia, através da coleta, quantificação e caracterização deste material. As coletas foram de 24 h com escala de amostragens do terceiro dia, e foram realizadas no período de julho de 2002 a junho de 2003. Foram utilizados dois amostradores: um de grandes volumes, High Vol, e um de pequenos volumes, Dicotômetro, que realiza o fracionamento do MPIO em duas frações: fina (MP:S: 2,5 J!m) e grossa (2,5 J!m < MP ::;; 10 J.lm). Após coleta do MPJO, a concentração do mesmo foi determinada através de análises gravimétricas. Os filtros de microfibra de quartzo usados no High Vol foram analisados através da técnica de volumetria gasosa para determinar as frações de carbono orgânico (COrg.) e carbono elementar (CE) presentes no MPIO e análises de dessorção térmica para determinação de compostos orgânicos voláteis (COV's) no material coletado. Os filtros de teflon usados no Dicotômetro foram analisados por iluorescência de raios X por energia dispersiva (EDXRF) visando à caracterização elementar do MP1O coletado. Os resultados obtidos comprovam que a concentração de material particulado no inverno, estação mais seca, é maior que no verão e que há um comportamento sazonal da concentração de MPJO ao longo do ano. Foram verificadas três ultrapassagens do padrão diário estabelecido pelo CONAMA (150 J.lglm3) e também ultrapassagem do padrão anual (50 J.lglm3). O Padrão diário (65 J.lglm3) estabelecido pelo EPA para MP2,5 foi ultrapassado três vezes durante o período e também foi observada a ultrapassagem do padrão anual que é de 15 J.lglm3. As análises das frações de carbono mostraram que as concentrações de CE foram superiores as de COrg. para o período, e através da caracterização elementar foi verificado que os elementos derivados de ressuspensão do solo são predominantes. Quanto aos resultados de dessorção de VOC's presentes no MPlO, os compostos benzeno e tolueno foram detectados em maiores quantidades. Palavras.chave: Material Particulado, MPlO, monitoramento atmosférico em Paulínia, qualidade do ar e poluição do ar / Abstract: The city of Paulinia, located 110 km far from São Paulo, has a population of 51000 inhabitants and also a large and complex industrial area that discharges dayly !arge volumes of pollutants ln the atmosphere, changing the qualíty of the air in the region. Among these pollutants, the inhalable particulate matter (particles smaller than 10 }!m in diameter, PMIO) i5 of great interest since these parti eles penetrate the human respiratory system and can reach the lung alveolus causing serious damage to health. This work focused on the monitoring and characterizatioD of PMJO present iD the atmosphere of the João Aranha neighborhood in Paulínia through sampling, quantification and characterization of the inhalable particulate matter. The sampiing consisted of a 24-hour sample every three days; it was conducted between July of 2002 and June of 2003. Two sampling methods were used: a high volume sampler, also known as High Vol, and a small volume sampler, called Dichotometer, that collects the particuJate matter as two Íractions: fine (pM _ 2.5 Jlm) and coarse (2.5 Jlm < PM _ 10 Jlm). After the PMIO sampling, its concentration was deterrnined through gravimetrical anaJysis. The micro fiber quartz filters used with the High Vol were subject to gaseous volumetry technique to determine organic and elementaJ carbon fractions present in the sampled PMlO and also to therrnal desorption analysis to determine the volatile organic compounds in the sampled matter. The Teflon filters used with the Dichotometer were analyzed Energy Dispersive X-Ray Fluorescense aiming the elemental characterization of the sampled PMIO. The obtained results show that the concentration of particulate matter is higher during the winter, the dry winter season. as compared to summer and that there is a seasonal factor in the PMIO concentration behavior through the year. Three samples violated the daily standard established by the Brazilian regulatory organization CONAMA (150 Jlglm3) and the annual standard (50 Jlglm3) was also violated. The daily standard (65 /.tglm3) established by EPA for PM2,5 was violated 3 times during the period and the annual standard of 15 /.tglm3 was also violated. The carbon fraction analysis showed that the concentrations of elementary carbon surpassed the organic carbon fractions for the samp!ed period, and through elemental characterization it was verified that elements generated by resuspended soil dominated the samples. Regarding the results of desorption of volatile organic components present in the PMlO. Benzene and Toluene showed high concentrations. Keywords: Particulate Matter. PMlO, atmospheric monitoring in Paulínia, air quality and pollution / Doutorado / Engenharia de Processos / Doutor em Engenharia Química
202

Cladonia verticillaris (líquen) como biomonitor padrão da qualidade do ar no distrito de Jaboatão-PE

SILVA, Rita Alves January 2002 (has links)
Made available in DSpace on 2014-06-12T18:07:39Z (GMT). No. of bitstreams: 2 arquivo8344_1.pdf: 2911564 bytes, checksum: b1951dd981c6652122c54a6c2a84a7e5 (MD5) license.txt: 1748 bytes, checksum: 8a4605be74aa9ea9d79846c1fba20a33 (MD5) Previous issue date: 2002 / Os liquens são reconhecidos como bioindicadores de ambientes e biomonitores da qualidade do ar atmosférico. Neste trabalho selecionou-se o Distrito de Jaboatão, situado na Mesoregião Metropolitana do Recife (RMR), Pernambuco, Brasil, para avaliar a qualidade do ar naquela área, correlacionando os dados fornecidos pelos monitores biológicos liquens, com os resultados obtidos das estações de monitoramento mecânico instaladas pela Companhia Pernambucana de Meio Ambiente (CPRH). Líquen da espécie (Raddi.) Fr. foi o biomonitor utilizado. A espécie foi coletada sobre solos arenosos de tabuleiros costeiros (cerrado) da Paraíba, nas seguintes localidades: Mamanguape, na Reserva Biológica de Guaribas, e em Alhandra, às margens da BR 101 (PB). Os biomonitores ativos foram coletados e acondicionados em recipientes plásticos, bem como o solo de área de ocorrência. Experimentos de transplante do material liquênico foram montados junto às estações de medição da CPRH localizadas na Estação do Metrô (ponto 1) e da CHESF (ponto 2) no referido distrito. As amostras de ambas as localidades foram coletadas em março de 2000, e imediatamente expostas ao ambiente nos pontos de experimento. Após 12 e 18 meses de exposição aos poluentes amostras foram retiradas e analisadas, química e fisiologicamente. Foram quantificados por Espectrômetro de Emissão Atômica por Plasma Indutivamente Aplicado (ICP/AES) os teores de Pb, Cd, Fe, Cu, Mn, Zn, Cr, Ni e Ca. Parte das mesmas amostras foram extraídas por sistema de esgotamento a frio com acetona, e analisadas por cromatografia em camada delgada (CCD) e cromatografia líquida de alta eficiência (CLAE) para identificação e quantificação dos fenóis liquênicos nas amostras. Filtros dos amostradores de grandes volumes (Hi-vol) da CPRH foram analisados, e neles quantificados Pb, Cd, Fe, Cu, Mn, Cr, Zn e Ni. Para este experimento foram consideradas as amostras representativas para as maiores concentrações mensais de Poeira Total em Suspensão (PTS), cujos filtros foram recolhidos no mesmo período em que os biomonitores. Os metais pesados supra referidos foram determinados via Espectrofotometria de Absorção Atômica por Chama (EAA). Para averiguação do comportamento de" % sob condições laboratoriais, foram montados experimentos onde amostras do líquen foram diariamente borrifadas com soluções de acetato de chumbo de chumbo a 1%, 0,1%, e água deionizada como controle. Foram coletadas amostras a 24h, 48h, 5dias e 10 dias, sendoposteriormente analisadas, segundo os mesmos parâmetros já referidos para o material exposto às condições ambientais. Ao final, as amostras mais preservadas e as em maior estado de deterioração, tanto as de experimento em campo, como as de laboratório, foram analisadas por microscopia eletrônica de varredura. Os resultados demonstraram que todas elas tiveram prejuízo na síntese de fenóis comuns da espécie. Análises em CCD e CLAE comprovaram a ocorrência de substâncias distintas das detectadas nas amostras padrão. Nos ensaios em CLAE ficou comprovado que os poluentes prejudicaram a síntese de fenóis tanto no aspecto qualitativo (substâncias intermediárias das vias metabólicas), mas também no teor das substâncias produzidas no total. Foi evidenciada a produção do ácido protocetrárico, além do hipoprotocetrárico e seu aldeído, como compostos intermediários. Sugeriu-se que o baixo teor de substâncias, e/ou a produção de metabólitos intermediários das rotas metabólicas tenha sido causado por um prejuízo na fotossíntese do fotobionte, por acidificação da célula pelos poluentes, o bloqueio de reações enzimáticas pelos elementos que contaminaram o líquen, ou a associação desses fatores. Em relação à quantificação dos contaminantes, houve o predomínio do Pb, Fe, Ca, Mn , Zn e Cr nas amostras de líquen. Nos filtros recolhidos das estações de monitoramento mecânico, detectou-se em maior concentração o Fe, Cu, Mn e Zn. No material submetido ao acetato de chumbo de chumbo foi verificado que o número de dias de exposição (10) foi suficiente para prejudicar o líquen no aspecto fisiológico. Análises por microscopia eletronica de varrredura (MEV) revelaram uma total desordem na superfície do talo liquênico, após exposição aos poluentes. As células do fotobionte, não visualizadas nas amostras controle, foram facilmente expostas, tornando-se desprotegidas em meio com alto nível de contaminantes. Dados semelhantes foram obtidos para os experimentos em laboratório. A superfície de" iniciou um processo de esfoliação resultando na sua destruição. Foi possível concluir que a zona central da cidade, onde encontra-se a estação do Metrô, é a mais poluída, e que" % como biomonitor, demonstrou capacidade de registrar os mais ínfimos níveis de contaminantes, inclusive quanto a bioacumulação de elementos iônicos, nutrientes e tóxicos e, diante desse contexto, valida a sua utilização como mais um parâmetro para avaliação da qualidade ambiental, em especial do ar atmosféricosubsequently analyzed using the same parameters mentioned above for the material exposed to environmental conditions. At the end, the best preserved samples and a greater state of deterioration, both in the field of experiment, such as laboratory, were analyzed by scanning electron microscopy. The results showed they all had impaired synthesis of phenols common species. Analyses in TLC and HPLC confirmed the presence of substances other than those detected in standard samples. In trials it was proved that HPLC pollutants impaired synthesis of phenols in both the qualitative aspect (intermediates of metabolic pathways), but also the content of the substances produced in total. Was evidenced protocetrárico acid production, and its addition to hipoprotocetrárico aldehyde as intermediate compounds. It has been suggested that low levels of substances, and / or the production of intermediate metabolites of the metabolic pathways have been caused by a loss in the photobiont photosynthesis, acidification of the cell by pollutants, the blockade of enzymatic reactions of the elements that have polluted the lichen, or a combination of these factors. Regarding the quantification of contaminants, there was predominance of Pb, Fe, Ca, Mn, Zn and Cr in samples of lichen. In filters collected from monitoring stations mechanic, was detected at higher concentration Fe, Cu, Mn and Zn. In material submitted to the lead acetate Lead was found that the number of days of exposure (10) was sufficient to affect the lichen physiological aspect. Analysis by electron microscopy varrredura (SEM) revealed a total disorder in the surface of the lichen thallus, after exposure to pollutants. The photobiont cells, not seen in samples control, were easily exposed, making it unprotected in a medium with high of contaminants. Similar data were obtained for the experiments the laboratory. The surface? " ? ?????? ? initiated a process of exfoliation resulting in its destruction. It was concluded that the downtown area, where is the subway station, is the most polluted, and that? " ? ?????? ?% As biomonitor showed ability to record the smallest levels of contaminants, including as to bioaccumulation of ionic elements, nutrients and toxic and, given this context, validates its use as an additional parameter for the assessment of environmental quality, in particular the atmospheric air.
203

Bulldozing Biodiversity: The Economics of Optimal Extinction

Spash, Clive L. January 2015 (has links) (PDF)
Many conservationists have become enamoured with mainstream economic concepts and approaches, described as pragmatic replacements for appeals to ethics and direct regulation. Trading biodiversity using offsets is part of the resulting push for market governance that is promoted as a more efficient means of Nature conservation. In critically evaluationg this position I start by explaining the assumptions behind biodiversity and ecosystem valuation and how economic logic legitimises, rather than prevents, ongoing habitat destruction and treats species extinction as optimal. Biodiversity offsets provide a means for operationalising trade-offs that are in the best interests of developers and make false claims to adding productive new economic activity. Contrary to the argument that economic logic frees conservation from ethics, I expose the ethical premises required for economists to justify public policy support for offsets. Finally, various issues in offset design are raised and placed in the context of a political struggle over the meaning of Nature. The overall message is that, if conservationists continue down the path of conceptualising the world as in mainstream economic textbooks they will be forced from one compromise to another, ultimately losing their ability to conserve or protect anything. They will also be abandoning the rich and meaningful human relationships with Nature that have been their raison d'être. (author's abstract) / Series: SRE - Discussion Papers
204

Caractérisation des domaines N-terminal et de liaison à l'ADN du récepteur des androgènes par des approches biophysiques / Biophysical caracterisation of N-terminal and DNA Binding domains of the androgen receptor

Meyer, Sandra 14 December 2015 (has links)
Cette thèse se situe à l’interface entre la biologie et la biophysique. Les méthodologies utilisées recouvrent principalement la résonance magnétique nucléaire (RMN), la diffusion des rayons X aux petits angles (SAXS), le dichroïsme circulaire (CD) et la spectroscopie de fluorescence. Une première partie vise à étudier le domaine de liaison à l’ADN (DBD) du récepteur des androgènes (AR) et les déterminants de l’interaction avec l’ADN. Une mutation faux-sens dans le DBD altère la spécificité de reconnaissance de l’ADN du récepteur bien que la structure tridimensionnelle soit identique au DBD sauvage. Les résultats montrent un changement dans la dynamique du récepteur mutant entrainant une déstabilisation de l’homo-dimère.La seconde partie de ma thèse consiste à établir un lien séquence/fonction au niveau du domaine N terminal (NTD) de AR. D’après la littérature, cette région joue un rôle important pour l’activité du récepteur, et elle est également décrite comme étant intrinsèquement désordonnée. Les résultats révèlent que cette région établit des contacts transitoires avec le DBD. Ceci suggère l’existence d'un couplage allostérique entre le DBD et les résidus adjacents sur le NTD.Ce couplage modifie l'ensemble conformationnel accessible au NTD en favorisant une conformation en hélice-α. / My PhD project is at the boundary between biology and biophysic. Methods used include nuclear magnetic resonance (NMR), small ange X-ray scattering (SAXS), circular dichroïsm (CD) and fluorescence spectroscopy. The androgen receptor (AR) DNA binding domain (DBD) and its interaction with DNA was studied in a first part. A mutation in the DBD leads to a modified DNA recognition by the mutant compared to the wild-type. Our results indicate changes in dynamic of the mutant receptor that leads to the homodimer destabilisation.The second part of my project aim to establish a link between sequence and function of the AR N terminal domain (NTD).As described in literature, this region is involved in the activity of the receptor and is also an intrinsically disordered protein (IDP). The results obtained during my thesis indicate that this region is involved in transient contact with the DBD. This suggest an allosteric coupling between the DBD and the neighboring residues on the NTD.This coupling modifies the conformational ensemble accessible to the NTD by stabilizing a α-helix conformation.
205

Entendendo a mutagenicidade de amostras de material particulado atmosférico = Understanding the mutagenicity of atmospheric particulate air samples / Understanding the mutagenicity of atmospheric particulate air samples

Morales, Daniel Alexandre, 1981- 02 May 2013 (has links)
Orientador: Gisela de Aragão Umbuzeiro / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Tecnologia / Made available in DSpace on 2018-08-22T02:22:25Z (GMT). No. of bitstreams: 1 Morales_DanielAlexandre_M.pdf: 1734694 bytes, checksum: adaccd3cf62c01d1ccd7421b7f9b99e4 (MD5) Previous issue date: 2013 / Resumo: O fracionamento de uma mistura complexa, como o extrato orgânico do material particulado de ar, com base nas diferentes características físicas e químicas dos seus componentes acoplada a testes de mutagenicidade e análises cromatográficas, vem sendo um procedimento útil na elucidação de quais substâncias está presentes na mistura. Este trabalho foi realizado em colaboração com outro grupo de pesquisa em um projeto temático financiado pela FAPESP, e seu objetivo foi estudar a mutagenicidade de frações de extratos orgânicos de material particulado de ar, utilizando ensaio Salmonella/microssoma em microssuspensão com os pares de linhagens TA98/YG1041, TA98/TA1538 e TA1538/YG5161 de Salmonella typhimurium que apresentam diferentes sensibilidades para grupos específicos de compostos. Também foi objetivo do trabalho comparar as potências mutagênicas obtidas para cada uma das frações com os níveis de hidrocarbonetos policíclicos aromáticos analisados pelos pesquisadores do projeto temático. Foram avaliadas três frações, Nitro-HPA, Oxi-HPA e HPA utilizando o método Salmonella/microssoma em microssuspensão na presença e ausência de ativação metabólica (mistura S9) em experimentos de dose-resposta, com quantidade máxima de 10 m³ por placa; também foi avaliada a contribuição na mutagenicidade dos hidrocarbonetos policíclicos aromáticos analisados para cada fração. De acordo com a contribuição na mutagenicidade dos compostos identificados, foi possível inferir que esses não explicam totalmente a mutagenicidade observada para algumas linhagens, e que outros compostos podem estar causando esse efeito. A comparação dos perfis observados entre as frações analisadas e os compostos químicos encontrados na literatura utilizando os pares de linhagens foi capaz de fornecer alguns grupos que podem justificar a mutagenicidade observada, porém, faltam estudos com compostos químicos puros. Um estudo utilizando os pares de linhagens com compostos químicos pode ajudar a identificar e entender o perfil das respostas observadas em amostras ambientais de material particulado de ar, bem como em outras amostras ambientais, especialmente em análises químicas direcionadas pelo efeito biológico (ADEB) / Abstract: The fractionation of a complex mixture based on different physical and chemical characteristics of its components coupled to mutagenicity testing and chromatographic analyzes have been useful in elucidating what substances are present in the mixture. This work was performed in collaboration with another research group in a broad thematic project funded by FAPESP. Samples were collected extracted and prepared by the participants and in this work the objective was to study the mutagenicity of fractions of organic extracts of air particulate matter using Salmonella/microsome microsuspension in combination with selective pair of strains TA98/YG1041, TA98/TA1538 and TA1538/YG5161 of Salmonella typhimurium which have different sensitivities to specific types of compounds. Another objective was to compare the mutagenic potencies obtained for each of the fractions with the levels of polycyclic aromatic hydrocarbons analyzed by the researchers of the thematic project. We evaluated three fractions, named as Nitro-PAH, Oxy-PAH and PAH, using the Salmonella/microsome microsuspension protocol in the presence and absence of metabolic activation (S9) in dose-response experiments, with maximum of 10 m³ per plate, was also evaluated the contribution of mutagenicity in polycyclic aromatic hydrocarbons for each fraction analyzed. According to the contribution in the mutagenicity of the compounds identified, it was possible to infer that these do not fully explain the mutagenicity observed for some strains, and that other compounds may be causing this effect. The comparison of the profiles observed between fractions and analyzed the chemical compounds found in the literature using the pairs of strains was able to provide some groups which may justify the mutagenicity observed, however, there are few studies with pure chemicals. A study using pairs of strains with single chemicals could help in the identification and understanding of the profile of the responses seen atmospheric air particulate samples as well as in other environmental samples, and so assist chemical analysis studies in effect directed analysis (EDA) / Mestrado / Tecnologia e Inovação / Mestre em Tecnologia
206

[pt] ANÁLISE TEÓRICO-EXPERIMENTAL DE UM DESUMIDIFICADOR DE AR USANDO TRI-ETILENO GLICOL / [en] THEORETICAL AND EXPERIMENTAL ANALYSIS OF AN AIR DEHUMIDIFIER USING TRIETHYLENE GLYCOL

31 October 2011 (has links)
[pt] Como parte de um sistema solar de condicionamento de ar por resfriamento evaporativo, foi projetado e construindo um desumidificador de ar utilizando tri-etileno glicol como agente higroscópio líquido. O modelo teórico desenvolvido, baseado no procedimento adotado para cálculo de torres de resfriamento. Levou em consideração o abaixamento de pressão de vapor na superfície líquido-gás assim como o calor de mistura de tri-etileno glicol e água. Os dados experimentais obtidos concordam satisfatoriamente com os resultados previstos pelo modelo teórico proposto, dentro das faixas de vazão pesquisadas. Uma correlação semi-empírica foi desenvolvida para cálculo dos coeficientes de difusão de desumidificadores de ar como função das vazões das fases líquida e gasosa. Finalmente é sugerido um procedimento para projeto de desumidificadores de ar de características semelhantes ao modelo proposto. / [en] As part of solar evaporative cooling air conditioning system, using tri-ethylene glicol as a liquid dehumidifier, an absortion tower was designed and built for drying air. The theory of heat and mass transfer between liquid and gas was developped following the same procedure as usually adopted for cooling tower calculations.The lowering of vapor pressure and the heat of solution were taken into account. Experimental data agree reasonably with theory within a wide range of flow rates. A correlation was developped relating mass transfer coefficients to liquid and gás flow rates. A procedure is finally suggested for designing and estimating the performance of na absortion tower.
207

Comparative Dating of a Bison-Bearing Late-Pleistocene Deposit, Térapa, Sonora, Mexico

Bright, Jordon, Kaufman, Darrell S., Forman, Steven L., McIntosh, William C., Mead, Jim I., Baez, Arturo 01 December 2010 (has links)
A recently discovered Bison-bearing fossil locality at Térapa, Sonora, Mexico, had previously been dated to 440 ± 130 ka using whole rock 40Ar/39Ar on a basalt flow that impounds the deposit. This age is considerably older than the accepted age of about 240-160 ka for the migration of Bison into greater North America. The Térapa deposit also contains a mixture of fossils from extralimital or extinct tropical animals and temperate animals. Constraining the age of the deposit is critical to interpret the paleontologic and paleoclimatologic implications of this unique Sonoran fossil locality. Three additional geochronological methods have been applied to this deposit (infrared stimulated luminescence (IRSL), amino acid racemization (AAR), and radiocarbon) and the data from the original 40Ar/39Ar age were revisited. The IRSL data suggest that the impounding basalt flow and the sediments that abut it were emplaced 43 ka ago and that the oldest sediments were deposited shortly after. Two radiocarbon ages suggest the fossiliferous sediments were emplaced by 42 ka. Effective diagenetic temperatures inferred from the AAR results, combined with AAR data from a similar-age deposit in southern Arizona, are in accordance with the 40-43 ka age estimates. For the AAR results to corroborate the 40Ar/39Ar age, the effective diagenetic temperature for the area would need to be approximately 3 °C, which is unrealistically low for northern Mexico. The new geochronological results suggest the Térapa deposit and fossils are 40-43 ka old. The anomalously old 40Ar/39Ar age for the impounding basalt is probably the result of low 40Ar* concentrations and inherited 40Ar.
208

Reconstruction de l'histoire des volcans de l’arc équatorien : contraintes pour l’évolution chronologique de l’arc andin et pour l'évaluation du risque volcanique / Reconstruction of the eruptive history of Ecuadorian volcanoes : constraints on the evolution of the Andean arc and for the assessment of volcanic hazards

Bablon, Mathilde 09 November 2018 (has links)
L’arc équatorien est caractérisé par un nombre particulièrement élevé de volcans quaternaires. Nos quatre-vingt-dix nouveaux âges K-Ar, réalisés pour une vingtaine d’édifices, montrent que son développement a commencé vers 1 Ma au nord et a migré vers le sud à partir de 600 ka. Ce déplacement pourrait être induit par un changement récent de la géométrie de la plaque Nazca en profondeur et l'activation des failles crustales. Les taux de production magmatique sont assez homogènes à l’échelle de l’arc, et varient entre 0,1 et 5,6 km³.ka⁻¹. Ces données montrent que les volcans se sont construits lors de phases d’activité brèves, séparées par des périodes de repos. Il n'y a pas de corrélation apparente entre l'âge des volcans et leur taux d'émission, mais la subduction de la ride de Carnegie pourrait favoriser la genèse du magma et expliquer la densité de volcans quaternaires en Équateur. Les taux d'érosion varient entre 0,01 et 0,14 km³.ka⁻¹. Les volcans les plus jeunes semblent être érodés par des processus d'altération chimique, tandis que les volcans plus anciens sont principalement démantelés par des processus physiques tels que l'abrasion glaciaire et l'activité tectonique. Enfin, nous montrons que la méthode de datation K-Ar réalisées sur la mésostase ou les esquilles de verre des ponces est bien adaptée pour dater les produits volcaniques quaternaires de l'arc équatorien. / The Ecuadorian arc presents a large number of Quaternary volcanoes. Our ninety new K-Ar ages, carried out on products from twenty volcanic edifices, show that the development of the Quaternary arc began about 1 Ma in northern Ecuador and migrated southward since 600 ka. This migration could be induced by recent change of the slab geometry at depth and by the activation of crustal faults. The magmatic productivity rates are rather homogeneous at the arc scale, and range between 0.1 and 5.6 km³.ka⁻¹. These data highlights that volcanoes grew during sporadic activity pulses separated by quiescence periods. There is no clear correlation between the age of the volcanoes and their emission rates, but the subduction of the Carnegie ridge could favor the magma genesis and explained the increase of the volcanic activity in northern Ecuador during the Quaternary. Erosion rates range between 0.01 and 0.14 km³.ka⁻¹. Youngest volcanic edifices seem to be eroded by a chemical alteration process, while the dismantling of older volcanoes is mostly influenced by physical processes such as glacial abrasion and tectonic activity. Finally, we show that K-Ar ages performed on groundmass or pumice glass shards can be successfully applied to Quaternary volcanic products from the Ecuadorian arc.
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Re-design and usability improvement of Arvue : an AR application displaying house models in their real context

Edström, Maja January 2024 (has links)
Building your own house may be the biggest decision and greatest investment of your life, which calls for an informed decision regarding the house design. However, two-dimensional drawings may lack external context and might, for untrained eyes, not communicate how the house will look on its intended site. With the use of augmented reality, the company Softhouse Neava AB has developed an application, Arvue, that gives users the ability to display digital house models in full scale at their intended site. Arvue is intended to help architectural firms in communicating house designs with their clients and through this, enhance their clients' experience of the designing process and decision making process. However, the user interface of Arvue lacks in usability, and when creating the interface, no usability testing was conducted. The objective of this thesis is to re-design the user interface of Arvue, with the aim to enhance its usability.  The prototype was developed using the design thinking process, which was iterated two times. This process consists of five phases - empathize, define, ideate, prototype and test. During the empathize phase, potential users were interviewed about their thoughts on usability and their knowledge and thoughts on AR. During the define phase, personas and user need statements were created based on the interview data. The user need statements were then used as a base for the brainstorming sessions in the ideate phase. Finally, a prototype was created and usability tested in two iterations.  To measure if the aim of this thesis was met, the System Usability Scale was used to grade both the current user interface of Arvue and the prototype, to compare the results. The current user interface scored an average of 49,5 or a grade F, meaning that the usability is below average. The prototype scored an average of 88 or a grade A+, meaning that the usability is above average. This indicates that the usability of the user interface has been enhanced, and thereby the aim of the thesis has been met. / Att bygga hus kan vara det största beslutet och den största investeringen i ditt liv, vilket kräver ett välinformerat beslut angående husets design. För otränade ögon kan det dock vara svårt att föreställa sig tvådimensionella ritningar på sin avsedda plats. Med hjälp av augmented reality har företaget Softhouse Neava AB utvecklat en applikation, Arvue, som ger en möjlighet att visa digitala husmodeller i verklig skala på deras avsedda plats. Arvue är avsedd att hjälpa arkitektfirmor att kommunicera husdesigner med sina kunder och genom detta förbättra sina kunders upplevelse av designprocessen och beslutsprocessen. Användargränssnittet för Arvue lider dock av bristande användarvänlighet, och användbarhetstester utfördes inte vid skapandet av användargränssnittet. Målet med denna uppsats är att omdesigna användargränssnittet för Arvue med syfte att förbättra dess användarvänlighet.  Prototypen utvecklades med hjälp av design thinking-processen, som itererades två gånger. Denna process består av fem faser - empathize, define, ideate, prototype och test. Under empathizefasen intervjuades potentiella användare om deras tankar kring användarvänlighet och deras kunskap och tankar kring AR. Under definefasen skapades sedan personas och user need statements baserat på intervjudatat. Detta användes sedan som grund för brainstormingsessioner i ideatefasen. Slutligen skapades en prototyp som användbarhettestades i två iterationer.  För att mäta om syftet med uppsatsen uppnåddes användes System Usability Scale för att betygsätta både det nuvarande användargränssnittet för Arvue och prototypen, för att sedan kunna jämföra resultaten. Det nuvarande användargränssnittet fick ett genomsnittligt poäng på 49,5 eller betyget F, vilket innebär att användarvänligheten är under genomsnittet. Prototypen fick ett genomsnittligt poäng på 88 eller betyget A+, vilket innebär att användarvänligheten är över genomsnittet. Detta tyder på att användarvänligheten för användargränssnittet har förbättrats och att syftet med uppsatsen har uppnåtts.
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Tectonometamorphic evolution of an allocthonous terrane , Gory Sowie Block, northeastern Bohemian massif (Poland)

Zahniser, Stephen J. January 2004 (has links)
No description available.

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