Bones are the principal structural components of a skeleton; they provide the body with unique roles, such as its shape maintenance, protection of internal organs and transmission of muscle forces among body segments. Their structural integrity is vital for the quality of life. Unfortunately, bones can only sustain loads until a certain limit, beyond which it fails. Usually, the reasons for bone fracture are traumatic falls, sports injuries, and engagement in transport or industrial accidents. The stresses imposed on a bone in such activities can be far higher than those produced during normal daily activities and lead to fracture. Understanding deformation and fracture behaviours of bone is necessary for prevention and diagnosis of traumas. Even though, in principle, studying bone's deformation and fracture behaviour is of immense benefit, it is not possible to engage volunteers in in-vivo investigations. Therefore, by developing adequate numerical models to predict and describe its deformation and fracture behaviours, a detailed study of reasons for, and ways to prevent or treat bone fracture could be implemented. Those models cannot be formulated without a set of experimental material data. To date, a full set of bone's material data is not implemented in the material data-base of commercial finiteelement (FE) software. Additionally, no complete set of data for the same bone can be found in the literature. Hence, a set of cortical bone's material data was experimentally measured, and then introduced into the finite-element software. A programme of experiments was conducted to characterise mechanical properties of the cortical bone tissue and to gain a basic understanding of the spatial variability of those properties and their link to the underlying microstructure. So, several types of experiments were performed in order to quantify mechanical properties of the studied bone tissue at macro- and microscales under quasi-static and dynamic loading regimes for different cortex positions called anterior, posterior, medial and lateral. Those experiments included: (1) uniaxial tension and creep tests to obtain its elastic, plastic and viscoelastic properties; (2) nanoindentation tests to characterise its microstructural elastic-plastic properties; (3) Izod tests to investigate its fracture properties under impact bending loading; (4) tensile-impact tests to characterise its impact strength and fracture force when exposed to a longitudinal loading regime. All the experiments were performed for different cortex positions and different directions (along the bone axis and perpendicular to it) when possible. Based on the results of those experiments, a number of finite-element models were developed in order to analyse its deformation and fracture using the extended finiteelement method (X-FEM) at different length scales and under various loading conditions. Those models included: (1) two-dimensional (2D) FE models to simulate its fracture and deformation at microscale level under quasi-static tensile loading. Additionally, the effect of the underlying microstructure on crack propagation paths was investigated; (2) 2D and three-dimensional (3D) FE models to simulate its fracture and deformation at macroscale level for the Izod impact test setup. In addition, the applicability of different constitutive material models was examined; (3) 3D FE models to simulate its fracture and deformation at macroscale level for tensile-impact loading conditions. The developed models provided high-quality results, and most importantly, they adequately reflected the experimental data. The main outcome of this thesis is a comprehensive experimental analysis and numerical simulations of the deformation and fracture of the cortical bone tissue at different length scales in response to quasi-static and dynamic loading. Recommendations on further research developments are also suggested.

abstract: Both volcanism and impact cratering produce ejecta and associated deposits incorporating a molten rock component. While the heat sources are different (exogenous vs. endogenous), the end results are landforms with similar morphologies including ponds and flows of impact melt and lava around the central crater. Ejecta from both impact and volcanic craters can also include a high percentage of melted rock. Using Lunar Reconnaissance Orbiter Camera Narrow Angle Camera (LROC NAC) images, crucial details of these landforms are finally revealed, suggesting a much more dynamic Moon than is generally appreciated. Impact melt ponds and flows at craters as small as several hundred meters in diameter provide empirical evidence of abundant melting during the impact cratering process (much more than was previously thought), and this melt is mobile on the lunar surface for a significant time before solidifying. Enhanced melt deposit occurrences in the lunar highlands (compared to the mare) suggest that porosity, target composition, and pre-existing topography influence melt production and distribution. Comparatively deep impact craters formed in young melt deposits connote a relatively rapid evolution of materials on the lunar surface. On the other end of the spectrum, volcanic eruptions have produced the vast, plains-style mare basalts. However, little was previously known about the details of small-area eruptions and proximal volcanic deposits due to a lack of resolution. High-resolution images reveal key insights into small volcanic cones (0.5-3 km in diameter) that resemble terrestrial cinder cones. The cones comprise inter-layered materials, spatter deposits, and lava flow breaches. The widespread occurrence of the cones in most nearside mare suggests that basaltic eruptions occur from multiple sources in each basin and/or that rootless eruptions are relatively common. Morphologies of small-area volcanic deposits indicate diversity in eruption behavior of lunar basaltic eruptions driven by magmatic volatiles. Finally, models of polar volatile behavior during impact-heating suggest that chemical alteration of minerals in the presence of liquid water is one possible outcome that was previously not thought possible on the Moon. / Dissertation/Thesis / Doctoral Dissertation Geological Sciences 2016

La lutte contre l'eutrophisation des grands lacs péri-alpins a permis une réduction des concentrations internes en phosphore, pour des réponses écologiques parfois mitigées. Dans le Léman, les concentrations en P ont été divisées par dix en trente ans pourtant la biomasse algale et la production primaire restent aussi élevées qu'au maximum de l'eutrophisation, malgré une augmentation de la transparence des eaux. Donc, bien que la concentration en phosphore soit une variable de forçage majeure des communautés planctoniques, il apparait nécessaire de considérer le rôle d'autres variables de forçage qui interagissent avec la concentration interne en nutriments pour comprendre les réponses écologiques des lacs aux mesures de reoligotrophisation. Les communautés planctoniques peuvent être impactées par les pratiques de la gestion appliquées d'autres compartiments du réseau trophique tels que les populations piscicoles. A l'effet de ces facteurs locaux s'ajoutent à l'impact du réchauffement climatique, un phénomène planétaire participant au changement global qui se manifeste à partir du début des années 1980, et dont l'impact est de mieux en mieux mis en évidence dans les lacs.Peu de lacs ayant fait ou font l'objet de suivis de routine, l'observation des effets de ces divers forçages anthropiques et la compréhension de leurs interactions se heurtent au faible nombre de base de données disponibles. En outre les données collectées ne permettent pas de remonter assez loin dans le temps pour couvrir entièrement la période au cours de laquelle les perturbations anthropiques se sont accrues. Elles ne permettent pas non plus d'étudier les conditions environnementales précédant cette période. La paléolimnologie à haute résolution (échelle annuelle et saisonnière) appliqué aux périodes récentes (dernier siècle) est une démarche alternative proposée pour palier cette absence de données instrumentales.Ce travail de thèse vise à comprendre comment les modifications des concentrations en nutriments, la gestion piscicole d'une espèce zooplantonophage, le corégone, et le changement climatique contribuent à modifier la structure et la diversité des communautés planctoniques de diatomées et de rotifères des grands lacs péri-alpins français depuis la fin du XIXe siècle.Les communautés planctoniques choisies ont chacune un fort potentiel bio-indicateur et une très grande importance dans la structure et le fonctionnement des écosystèmes lacustres. Les trois perturbations majeures et simultanées survenant lors de la période d'étude se présentent avec des intensités différentes dans les trois lacs. L'évolution temporelle de certains paramètres physico-chimiques au sein de ces lacs est déjà en partie connue grâce à un suivi de limnologie mis en place depuis plusieurs dizaines d'années.Les acquis de la thèse sont de divers natures. (i) développement méthodologique concernant la reconstruction paléolimnologique des communautés de rotifères à partir des banques d'œufs archivées dans les sédiments, (ii) reconstruction des les réponses écologiques des compartiments diatomiques et rotifèriens au cours du dernier siècle, (iii) de comparer ces trajectoires entre lacs afin de discriminer les réponses à des perturbations locales, de celles à des perturbations plus globales et (iv) d'améliorer notre compréhension des interactions entres toutes ces perturbations. / During the XXth century, lacustrine ecosystems have undergone deep changes due to increased human activities on lakes and their watershed. Although significant restoration efforts have been undertaken since the 1980's, their efficiency can be limited. For instance, although phosphorous concentrations of Lake Geneva have been cut by 10 in the last 30 years (for a total cost of four billlions euros), the algal biomass and the primary production remain as high as during the eutrophication maximum, even if water transparency increased. So, the counter-intuitive response of lakes to restoration measures emphasizes that although phosphorous concentration is a major driver of phytoplankton, there is a need to consider the interaction with other environmental drivers, such as climate or top-down controls. Another fence however to the understanding of lake recent response to restoration measures is the lack of long-term monitoring data.The objective of this Ph-D work is to investigate how three human perturbations, i.e. changes in nutrient concentrations, fisheries management practices and climate change, can explain the response of the planktonic communities of three peri-alpine lakes (Lakes Geneva, Annecy and Bourget), using a high-resolution paleolimnological approach conducted on recent time periods. More specifically, the objectives of this PhD are three-fold:(i) To perform the methodological development of the use of rotifer egg banks archived in sediment for paleolimnological reconstructions(ii) To perform methodological development of paleolimnolgical reconstruction of diatom sesaon variability(iii) To delineate ecological responses of diatom and rotifer communities facing anthropogenic perturbations over the last century(iv) To scale the impact of local versus global perturbations over these ecological trajectories

Dans le contexte de ressources limitées actuelles, il est nécessaire pour les pharmaciens de justifier la valeur ajoutée de leurs interventions pharmaceutiques (IP) formulées lors de l'analyse pharmaceutique (AP). L’objectif de ce travail de thèse est de mener une recherche sur les méthodes d'évaluation de la pertinence des IPs et développer un nouvel outil pour l’évaluation de l‘impact potentiel des IPs. Le travail se décompose en 3 grandes parties : (i) contexte de l’AP, et méthodes d'évaluation de l’impact des IPs, (ii) revue systématique des outils pour évaluer la pertinence potentielle des IPs, (iii) processus de développement et de validation du nouvel outil multidimensionnel - nommé CLEO pour évaluer l’impact potentiel des IPs. Les résultats de cette recherche apportent des éléments nouveaux pour l’évaluation et la démonstration de la valeur des IPs dans un objectif global de déploiement des services de pharmacie clinique. / In times of limited resources allocation, it is necessary for pharmacists to justify the added value of their pharmacist interventions (PIs) made during medication review (MR). The purpose of this thesis work is to research on methodologies of evaluation of value of PIs as well as development and validation of a new tool for assessing potential impacts of PIs. The work consists of 3 major parties: (i) context in which MR locates, characteristics of practice of MR, and methodologies of evaluation of impacts of PIs, (ii) systematic review of tools for assessing the potential significance of PIs in literature , (iii) process of development and validation of the new multidimensional tool - named CLEO for assessing potential impacts of PIs. The whole results of this research are useful to evaluate and demonstrate the value of PIs in efforts to expand clinical pharmacy services.

abstract: Impact craters are ubiquitous throughout the Solar System, formed by one of the principal processes responsible for surface modification of terrestrial planets and solid bodies (i.e., asteroids, icy moons). The impact cratering process is well studied, particularly on the Moon and Mercury, where the results remain uncomplicated by atmospheric effects, plate tectonics, or interactions with water and ices. Crater measurements, used to determine relative and absolute ages for geologic units by relating the cumulative crater frequency per unit area to radiometrically-determined ages from returned samples, are sensitive to the solar incidence angle of images used for counts. Earlier work is quantitatively improved by investigating this important effect and showing that absolute model ages are most accurately determined using images with incidence angles between 65&deg; and 80&deg;, and equilibrium crater diameter estimates are most accurate at ~80&deg; incidence angle. A statistical method is developed using crater size-frequencies to distinguish lunar mare age units in the absence of spectral differences. Applied to the Moon, the resulting areal crater densities confidently identify expansive units with >300&ndash;500 my age differences, distinguish non-obvious secondaries, and determine that an area >1&times;104 km2 provides statistically robust crater measurements. This areal crater density method is also applied to the spectrally-homogeneous volcanic northern smooth plains (NSP) on Mercury. Although crater counts and observations of embayed craters indicate that the NSP experienced at least two resurfacing episodes, no observable age units are observed using areal crater density measurements, so smooth plains emplacement occurred over a relatively short timescale (<500 my). For the first time, the distribution of impact melt on Mercury and the Moon are compared at high resolution. Mercurian craters with diameters &ge;30 km have a greater areal extent of interior melt deposits than similarly sized lunar craters, a result consistent with melt-generation model predictions. The effects of shaking on compositional sorting within a granular regolith are experimentally tested, demonstrating the possibility of mechanical segregation of particles in the lunar regolith. These results provide at least one explanation toward understanding the inconsistencies between lunar remote sensing datasets and are important for future spacecraft sample return missions. / Dissertation/Thesis / Ph.D. Geological Sciences 2013

Submitted by Fabio Sobreira Campos da Costa (fabio.sobreira@ufpe.br) on 2016-07-01T12:38:10Z No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) Dissertação-JoelsonIsidroDaSilvaAraújo.pdf: 1742206 bytes, checksum: c2b6f413666e50be58b963e8624a1386 (MD5) / Made available in DSpace on 2016-07-01T12:38:10Z (GMT). No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) Dissertação-JoelsonIsidroDaSilvaAraújo.pdf: 1742206 bytes, checksum: c2b6f413666e50be58b963e8624a1386 (MD5) Previous issue date: 2015-09-04 / CAPEs / Contexto: a mudança faz parte da evolução e durante o ciclo de vida do software a maior parte dos custos está associada a esta tarefa. Poder fazer previsões sobre os potenciais efeitos causados através de uma mudança é uma forma de minimizar esses custos. Neste contexto, surge então a Análise de Impacto (AI) para medir o esforço que será necessário à mudança e para nortear como realizar a mesma da maneira mais adequada, entretanto o resultado gerado pode ser insuficiente, pois é possível existirem erros na identificação dos elementos possivelmente impactados, não contemplando todos os problemas existentes. Objetivo: este trabalho tem como objetivo investigar o que se tem feito para permitir um resultado mais preciso na AI, gerando um catálogo de benefícios e limitações e propondo um guia de boas práticas, respondendo as perguntas de pesquisa – O que se sabe atualmente sobre os benefícios e limitações da AI em mudança de software? O que se tem feito para minimizar os erros gerados na análise? Método: para a condução da pesquisa fez-se necessário a busca de dados na literatura, através de uma pesquisa exploratória, por meio de uma revisão sistemática com o intuito de investigar as técnicas de AI relatadas em pesquisas dos últimos anos. Resultados: de posse dos dados resultantes da extração e análise dos dados, os resultados são: (1) evidências de técnicas existentes que conseguiram minimizar imprecisões nos resultados da análise, (2) geração de catálogo de benefícios e limitações em seu uso e ainda, um guia de propostas de boas práticas a serem adotadas para permitir que a análise apresente melhores resultados. Conclusão: os resultados fornecem uma melhor visão dos fatores que precisam ser melhorados e, além disso, possibilitaram a criação de um guia de boas práticas. Com isto, pretendemos contribuir fornecendo uma melhor compreensão sobre as técnicas existentes, de que forma melhorias vêm sendo propostas e quais práticas permitem a maximização dos resultados gerados através da análise de impacto. / Context: Changing is part of the evolution and during the software lifecycle most cost is associated with this task. Being able to make predictions about the potential effects caused by a change is a way to minimize these costs. In this context, the Impact Analisys (IA) can be used to measure the effort it will take to change and to guide how to do the same in the most appropriate way, however the results generated may be insufficient, it is possible to detect errors on the elements identification possibly impacted, not including all the existing problems. Objective: This study has the objetive to investigate what has been done to allow more accurate result in IA , generating a catalog of benefits and limitations and proposing a guide of good practice by answering the research questions - What is currently known about the benefits and IA limitations on software changes? What has been done to minimize errors generated in the analysis? Methodology: To conduct this research it is necessary to search data in the literature, through an exploratory research using a systematic review that will allow an investigation about the most IA techniques used in the last years. Results: With the data generated through the extration and analisys of data, the results are: evidences of techniques which can be used to minimize inaccuracies in test results, (2) generation of catalog of benefits and limitations in its use and also a good practice guide to be adopted to allow the analysis present better results. Conclusion: the expected results will provide a better view of the factors that need to be improved and, besides, will enable the creation of a good practice guide. With this, we intend to contribute by providing a better understanding of existing techniques, how improvements have been proposed and what practices has been used to improve the results generated by impact analysis.

Orientadores: Carlos Roberto de Souza Filho, Cristiano de Carvalho Lana / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Geociencias / Made available in DSpace on 2018-08-15T00:06:50Z (GMT). No. of bitstreams: 1 Machado_RogerioAmaro_M.pdf: 6890579 bytes, checksum: 4c4acd981fd71f6ac0d9f9db67e88ee3 (MD5) Previous issue date: 2009 / Resumo: Fundidos de impacto ricos em clastos e brechas de impacto pseudotaquilíticas são encontrados nos embasamentos cristalinos de muitas estruturas de impacto ao redor do mundo. São formados sob condições extremas de temperatura e pressão, geradas na colisão de um meteorito e também registram importantes pistas sobre os processos associados aos impactos em hipervelocidade e evolução planetária. Este trabalho forneceu importantes pistas sobre a produção, extração e cristalização das rochas fundidas na estrutura de impacto de Araguainha, no Brasil central. Os fundidos de impacto localizados no soerguimento central da estrutura são caracterizados por uma matriz de composição granítica rica em álcalis, envolvendo minerais e fragmentos de rochas derivados estritamente do granito impactado. Apesar da natureza mista das rochas impactadas neste evento (rochas sedimentares e graníticas) os dados de rocha total para os elementos maiores e menores (incluindo elementos do grupo da platina) indicam que o fundido foi gerado localmente, sem contato com a sequência sedimentar ou o bólido impactante. Similar a brechas pseudotaquilíticas, as rochas fundidas em Araguainha formaram-se isoladas, provavelmente abaixo da zona de fusão por impacto. A análise multispectral dos mapas químicos obtidos por raios-X e de química mineral do embasamento granítico e dos fundidos de impacto e seus clastos indicaram que o fundido originou-se por fusão seletiva do plagioclásio, feldspato potássico e biotita. O plagioclásio e o feldspato potássico fundiram-se discretamente e de forma isolada, produzindo domínios no fundido que combinam estequiometricamente com estes minerais. O fundido derivado da biotita mostrou maior mobilidade e misturou-se mais facilmente com os outros fundidos. Nenhuma evidência de fusão por fricção foi encontrada. Os fundidos em sua fase inicial migraram por uma densa rede de micro fraturas antes de serem incorporados pelos principais bolsões de rocha fundida. Evidências encontradas nesse trabalho indicam que fundidos produzidos localmente, como as brechas pseudotaquilíticas, são produzidos por fusão seletiva de minerais dentro da rocha impactada. Associou-se, desta forma, a fusão dos minerais com as temperaturas de pós-choques, que podem ter aumentado para além do ponto de fusão de feldspatos e biotita. / Abstract: Clast-bearing impact melts and pseudotachylitic breccias are found in crystalline target rocks of many impact structures around the world. They are formed under the extreme pressure-temperature conditions that accompany the meteorite collision, and record important clues to the process associated with hypervelocity impacts and planetary evolution. Here we provide important insights into the generation, extraction and crystallization of clast-laden melt rocks from the Araguainha impact structure in central Brazil. The melt bodies in the central uplift are characterized by an alkalai-rich granitic matrix embedding mineral and rock fragments derived strictly from granite target rocks. Despite the mixed nature of the target rocks - sedimentary and granitic rocks -bulk-rock major and trace element (including platinum group elements) data indicate that the granitic melts were generated locally, without direct contact with the sedimentary sequence or the projectile. Similarly to pseudotachylitic breccias, the Araguainha melt rocks formed in isolation, probably below the zone of impact melting. Multispectral analysis of X-ray maps and mineral chemistry from clasts and granitic targets indicate that the melt originated by selective melting of plagioclase, K-feldspar and biotite. Plagioclase and K-feldspar melted discretely and in isolation, producing domains in the melt which closely match the stoichiometry of these minerals. The biotite derived melt component appears to have been more mobile and mixed more readily with the other melts. No textural evidence for friction melting has been found. The initial melt phases have migrated through a dense network of microfractures before being assembled into main melt bodies. Evidence provided here indicates that locally produced melt bodies such as pseudotachylitic breccias, are produced by selective melting of minerals within the target rocks. We relate the melting of the minerals to the post-shock temperatures that may have risen beyond the melting point of biotite and feldspars. / Mestrado / Geologia e Recursos Naturais / Mestre em Geociências

A presente pesquisa foi conduzida a partir de consultas ao acervo de Estudos de Impacto Ambiental (EIAs) aprovados pela Fundação do Meio Ambiente de Minas Gerais, no período compreendido entre 1986 e 1999. O objetivo da pesquisa foi proceder a uma avaliação da concordância dos estudos sobre o meio biótico contidos nos EIAs consultados com a legislação que fornece as diretrizes básicas para estudos sobre o meio em questão. No desenvolvimento da pesquisa foram avaliados os estudos sobre a flora e a fauna silvestres não aquáticas, contidos em uma amostra representativa de 111 EIAS pertencentes a 5 setores e 25 tipos de atividades. Os estudos sobre a flora, bem como os estudos sobre a fauna, foram avaliados mediante o emprego de 7 variáveis legais subdivididas em 36 itens e 15 variáveis técnicas subdivididas em 67 itens. Ao todo, cada EIA selecionado para a pesquisa foi avaliado mediante a análise de 44 variáveis subdivididas em 206 itens . Os resultados obtidos revelaram que os estudos sobre o meio biótico contido nos Estudos de Impacto Ambiental não atendem satisfatoriamente às exigências legais previstas na regulamentação disciplinadora do tema, tanto em nível estadual como em nível federal. Tampouco atendem às recomendações técnicas básicas preconizadas para a condução de estudos sobre o meio em questão. No aspecto que se refere à concordância com a legislação, as principais falhas foram observadas nas variáveis legais relacionadas ao diagnóstico ambiental da área de influência do empreendimento impactante, à proposição de medidas mitigadoras dos impactos negativos e à proposição de programas de monitoramento dos impactos. Com relação ao atendimento das recomendações técnicas, foram identificadas falhas consistentes nas variáveis técnicas relacionadas à amplitude de duração dos estudos; à observação da sazonalidade, esforço amostral e replicação da amostragem durante a condução dos estudos; à comparação com estudos anteriores realizados em nível regional ou estadual: à realização de análises embasadas na vulnerabilidade das espécies; à realização de análise embasadas na aplicação de índices ecológicos; ao emprego de análises multivariadas, de padrões de distribuição e de espécie-abundância na condução dos estudos; e ao número de especialistas presentes na equipe executora dos estudos. Esses resultados indicam que os estudos sobre o meio biótico conduzidos nos EIAs apresentam qualidade duvidosa no aspecto que se refere ao rigor legal e técnico e impõem a necessidade de que tais estudos sejam revisados com mais critério pelo órgão ambiental e que sejam criados protocolos com maior fundamento técnico-científico para sua execução. / The present research work was carried out from consultations to the material of Environmental Impact Statements (EIS) approved by the Fundação Estadual do Meio Ambiente de Minas Gerais (State Foundation of Environment of Minas Gerais) over the period encompassed between 1986 and 1999. The objective of the research work was to proceed an evaluation of the agreement of the studies about the biotic mean contained in the EIS consulted with the legislation which furnishes the basic guidelines for it execution and with the technical-scientific guidelines for the study of the mean in issue. In the development of the research work were evaluated the studies of the non-aquatic wild flora and fauna,contained in a sample representative of 111 ElAs belonging to 5 sectors and 25 sorts of activities. The studies about the flora were evaluated by means of the use of 7 legal variables subdivided into 36 items and 15 technical variables subdivided into 67 items. In the same way, the studies on fauna were evaluated through the use of 7 legal variables subdivided into 36 items and 15 technical variables subdivided into 67 items. In whole, each EIS selected for the research work was assessed by means of the analysis of 44 variables subdivided into 206 items. The results obtained revealed that the studies upon the biotic mean contained in the Environment Impact Statement do not meet satisfactorily the legal demands foreseen in the disciplining regulation of the subject, both at the state and federal leveI. Neither, they meet the basic technical-scientific recommendations commended for the accomplishment of studies on the mean in issue. As far as the agreement is concerned with the legislation, the early failures were found in the legal variables concerned with the environmental diagnostic of the influence area of the impacting enterprise; with the proposition of mitigation measures and with the proposition of monitoring programs of the impacts. As regards the meeting of the technical-scientific recommendations, were identified consistent failures in the technical variables related with the range of the length of the studies; the observation of seasonality, samplal effort and replication of the sampling over the execution of the studies; the content of the listings of species presented in the studies; the comparison with previous studies performed at the regional or state level; the accomplishment of analyses based on the species vulnerability; the undertaking of analyses based on the application of ecological indices; the use of multivariate analyses, distribution patterns and of species-abundance in the accomplishment of the studies and the number of experts present in the team performing the studies. Those results point out, that the studies on the biotic mean conducted in the EIS present doubtful quality in the aspects concerned as far as the legal and technical-scientific rigor are concerned, and imposes the need that such studies be reviewed with more criterion by the environmental organ and be presented protocols with greater technical-scientific fundamentals for their accomplishment.

The environmental impact of the Robinson Deep mine residue deposit in Johannesburg was assessed by evaluating the water chemistry and surface precipitates, thereby identifying the processes responsible for forming the contamination footprint. Precipitates were compared to a documented paragenetic sequence of mineral formation associated with sulphide rich mine waste. PHREEQC, a geochemical modelling tool, was utilized to predict the formation of precipitates from evaporation ponds. The chemistry of the leachate was analysed and compared to water quality standards in order to determine the possible environmental impact. The chemistry of the water emanating from the mine residue deposit reveals that an Fe-SO4 dominant chemistry persists, this is consistent with acid mine drainage environments. The most toxic cations and anions contained in the water are Fe, Al, Mn, Ca, As, Mg, Cu, Zn, Pb and SO . It is predicted that the impact of toxic metals identified in the water decreases further from the mine residue deposit due to dilution and co-precipitation with different mineral phases such as goethite. Precipitates identified include jarosite group minerals, goethite, melanterite, copiapite, Mg-copiapite, halotrichite, pickeringite, gypsum and alunogen. These secondary minerals may be used as indicator minerals of acid mine drainage. Assessment and prediction of the stage of contamination and possible environmental impact, may, therefore be pursued when comparing the indicator minerals to predicted paragenetic sequences. For example, the precipitation of melanterite is consistent with an early stage of acid mine drainage development. The presence of melanterite thus suggests that oxidation of sulphides is an ongoing process on the Robinson Deep mine residue deposit. Evaporation of water in the evaporation ponds aids in increasing the concentration, hence allowing the predominant precipitation of jarosite group minerals. Alternatively, rainfall dilutes the water allowing dissolution of minerals located on the banks of the evaporation ponds to predominate. This mechanism of precipitation and dissolution is seasonal; formation of precipitates predominates during the dry season, while dissolution is most prominent during the wet season. The development of hardpans indicates that the main mechanism of formation of the associated phases is through capillary action at the sediment surface. Leaching of Fe2+-rich water from the mine residue deposit containment area is indicated by the presence of copiapite, while jarosite and goethite formation tend to form part of a hardpan layer. Goethite is an indication of a late stage mineral predominant at lower sulphate and higher pH conditions. Results of predicted formation of precipitates by PHREEQC are not in very good agreement with actual field observations. This is mainly due to the lack of thermodynamic data for many of the sulphate minerals observed. Hence, precipitates associated with acid mine drainage may be utilized as indicator minerals. Consequently, there identification may facilitate in environmental monitoring and risk assessment. / Prof. J. M. Huizenga Prof. J. Gutzmer

Afin de mieux comprendre et de mieux quantifier la formation des dommages d'impact et leurs conséquences sur la tenue de la structure composite, le recours à la simulation numérique semble être un complément indispensable pour enrichir les campagnes expérimentales. Cette thèse a pour objectif la mise au point d'un modèle d'impact pour la simulation numérique par éléments finis dynamique implicite, capable de prévoir les dommages induits.La première étape du travail a consisté à élaborer un modèle s'appuyant sur le modèle de comportement du pli « Onera Progressive Failure Model » (OPFM) et sur le modèle bilinéaire de zones cohésives proposé par Alfano et Crisfield, puis d'évaluer la sensibilité aux différentes composantes des lois de comportement de la réponse à un impact et des dommages prévus. Des essais d'impact et d'indentation sur des plaques stratifiées en carbone/époxy ont ensuite été réalisés, analysés et enfin confrontés aux résultats numériques, afin d'évaluer les performances à l'impact du modèle OPFM et ses limites.Ces travaux permettent d'aboutir à trois principales conclusions. Premièrement, l'usage de modèles de zones cohésives semble nécessaire pour prévoir la chute de force caractéristique de l'impact sur stratifiés. Deuxièmement, la prise en compte des contraintes hors plan, notamment les cisaillements, est indispensable pour prévoir correctement l'endommagement d'impact. Enfin, si le modèle OPFM est capable de prévoir qualitativement les dommages d'impact, l'absence de caractère adoucissant ou de viscoplasticité semble cependant limiter leur prévision quantitative. / In order to improve the understanding and the quantification of the impact damage formation and of their consequences on the composite structure behavior, numerical simulation seems to be a necessary complement to experiments. This thesis aims at designing an impact model suited for a dynamic implicit finite element numerical simulation, able to predict the induced damages.The first step of the work consisted in building an impact model using the ply behavior law “Onera Progressive Failure Model” (OPFM) and the bilinear cohesive law defined by Alfano and Crisfield, then in evaluating the impact response and the predicted damage sensitivity to the different parameters of the behavior laws. Impact and indentation tests on carbon/epoxy laminate plates have then been performed, analyzed and compared with the numerical results, in order to evaluate the impact performance of OPFM and its limits.This work points out three key results. First, the use of cohesive zone models seems necessary to predict the typical load drop. Secondly, the out-of-plane constraints, especially the shearing, must be taken into account to correctly predict impact damages. Finally, even if the OPFM model is able to qualitatively predict impact damages, the lack of softening or viscoplasticity seems to limit their quantitative prediction.