The demand for metals is great for the purpose of developing green technologies, and EU has listed 30 metals and minerals that are of critical importance for the maintenance and evolving of today’s society, so called critical materials. However, mining of raw materials generates mine waste which can have adverse effect on human health, ecosystems, and surrounding areas. To be able to prevent the release of toxic levels of elements from mine waste, an understanding of how different elements behave in the secondary environments is necessary in order to use the most successful methods for mining remediation. It is common that secondary minerals, such as gypsum and/or HFOs (hydrous ferric oxides), forms in mine waste or in downstream environments, depending on the geochemical conditions. From prior studies, it is well established that trace elements are sorbed by HFO. But studies are scares regarding co-precipitation of elements with secondary gypsum formation, and few studies investigates the possibility of critical elements to be captured by secondary minerals. In this study, a prior unknown white precipitation along with tailings material from the Smaltjärnen tailings beach in Yxsjöberg, Sweden, has been investigated by combining mineralogical studies (SEM-EDS and DXRD analysis) with sequential extraction. The aim with the study was to identify the precipitation and to examine if critical elements had co-precipitated with the precipitation and HFOs within the sample. From the results it was possible to prove that the white precipitation was gypsum (CaSO4*2H2O), and it was indicated that some of the critical elements (beryllium for instance) showed affinity for gypsum, and that bismuth, tungsten, and chromium were sorped by HFOs. The combining of chemical analysis with mineralogical studies was of great importance for determining in which mineral phases the leached elements were situated, and the study has shown that secondary gypsum formation can be an important sink for some critical elements. More studies should be performed within this field of research to further investigate the importance of secondary minerals for scavenging of elements, not only to prevent toxic levels to be leached, but also to capture these elements in the purpose of re-mining. / Idag är behovet av metaller stort inom användningsområden för att utveckla gröna teknologier. EU har därför listat 30 metaller och mineral (kritiska material) som anses vara kritiska för att underhålla och utveckla dagens samhälle. Men brytning av råmaterial resulterar i generering av gruvavfall där avfallet potentiellt kan utgöra en risk för att skada bland annat människors hälsa och ekosystem. För att kunna förhindra att giftiga halter av grundämnen släpps ut från gruvavfall så krävs en förståelse om hur olika ämnen beter sig i sekundära miljöer, för att på så sätt kunna tillämpa de mest framgångsrika metoderna för sanering och återställning av gruvområden. Det är vanligt förekommande att sekundära mineraler (såsom gips och järnhydroxider) fälls ut i gruvavfallet och/eller nedströms om gruvområdet beroende på de geokemiska förhållandena. Tidigare studier har visat att spårämnen kan binda till järnhydroxider, men endast ett fåtal studier undersöker samutfällning av olika spårämnen tillsammans med sekundärt gips. Hur specifikt kritiska metaller kan fångas upp av sekundära mineral är ännu inte välstuderat. I denna studie har en vit, tidigare okänd, utfällning provtagits från en av deponierna med anrikningssand i den historiska volframgruvan i Yxsjöberg. Utfällningen identifierades genom att kombinera mineralogiska studier (SEM-EDS och DXRD analys) med kemiska lakvattenanalyser från en sekventiell lakning. Målet med studien var att mineralogiskt karaktärisera den okända utfällningen och att undersöka om kritiska ämnen möjligen samutfällts tillsammans med de sekundära mineralen. Studien visade att utfällningen var sekundärt gips (CaSO4*2H2O) och det kunde påvisas att vissa kritiska metaller visade affinitet för gipset (exempelvis beryllium) och att andra kritiska metaller samutfällts/adsorberats av järnhydroxider. Att kombinera dom olika metoderna visade sig att vara till stor nytta för att kunna påvisa vilka mineral dom olika grundämnena var bundna till, och studien har även visat att sekundärt gips kan vara en sänka för vissa kritiska metaller. Mer studier bör utföras inom detta forskningsområde i framtiden för att vidare undersöka hur sekundära mineral kan binda kritiska metaller, inte endast för att förhindra att giftiga halter av metaller släpps ut, utan också för att undersöka möjligheten att återvinna gruvavfallet för utvinning av kritiska metaller.

The geology of the northeastern and southwestern sections of the aureole of the Loon Lake pluton of Chandos township was mapped. Thirty five pairs of hornblende and biotite were separated from the rocks and spectrographically analyzed for Be, Ga, Ti, Cr, V, Li, Ni, Co, Cu, Mn, Zr, Sr, Ba and Rb. Major element analyses were made by wet chemical methods on 8 pairs of hornblende and biotite. The relations of minor and major elements are discussed in terms of distribution coefficients. / Thesis / Master of Science (MS)

MOF-5 ist der Archetyp einer neuartigen Klasse hochporöser Materialien, den Metal Organic Frameworks, die unter anderem zur Anwendung als effektive Gasspeicher geeignet sind. Im Rahmen dieser Arbeit werden die seiner Bildung zugrunde liegenden Reaktionen untersucht. Aus den Erkenntnissen dieser Untersuchungen wurden zwei neue Syntheseverfahren entwickelt. Eines der Verfahren beruht auf der Phasenumwandlung von Zinkterephthalaten und ermöglichte die Laborsynthese von MOF-5 in 100 g-Mengen. Ein zweites Verfahren bedient sich des Strukturaufbaus mit Hilfe vorgefertigter anorganischer Cluster, wodurch erstmals die Synthese von MOF-5-Homologen anderer Metalle als Zink gelang.

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Mémoire numérisé par la Division de la gestion de documents et des archives de l'Université de Montréal.

Este trabalho teve como foco principal a caracterização espectroscópica dos haletos de berílio, BeCl, BeBr e BeI. O conhecimento acerca dessas espécies foi ampliado significativamente através do cálculo de parâmetros de difícil caracterização experimental. Como os poucos trabalhos experimentais realizados para esses haletos apresentam resultados inconclusivos para a transição C 2Σ+ - X 2Σ+, através do cálculo acurado de probabilidades de transição foi possível oferecer uma nova interpretação para os dados existentes, apresentando inclusive resultados para as outras transições eletrônicas até o presente desconhecidas. Cálculos utilizando o método de Interação de Configurações Multirreferencial (MRCI) com um conjunto de funções de base consistentes na correlação de qualidade quintupla-zeta foram utilizados para se obter as curvas de energia potencial associadas ao primeiro e segundo canais de dissociação para os estados dubleto e quarteto dessas espécies. Parâmetros espectroscópicos como as constantes vibracionais we, wexe, a constante rotacional Be e a distância de equilíbrio foram determinados para os estados de mais baixa energia. Além disso, foram calculadas a energia de excitação (Te) e a energia de dissociação (De) com e sem a inclusão de efeitos spin-órbita. Os resultados obtidos expandiram significativamente nosso conhecimento sobre os estados eletrônicos dessa espécies. Para os estados já investigados experimentalmente, houve boa coerência entre os parâmetros calculados e experimentais. As diferenças de energia entre os dois canais no limite de dissociação para as moléculas BeCl, BeBr e BeI obtidas neste trabalho foram, respectivamente: 21835, 21889 e 21998 cm-1, em concordância com o respectivo resultado experimental das três espécies (21980 cm-1). A determinação teórica da energia de dissociação D0 foi bastante satisfatória. Obtivemos 92,24; 72,77 e 51,75 kcal·mol-1, respectivamente, para as moléculas BeCl, BeBr e BeI incluindo os efeitos spin-órbita, comparados a 91,78, 71 e 57 kcal·mol-1. Para uma análise mais completa das curvas de energia potencial, elas também foram obtidas considerando-se os efeitos relativísticos. A constante de acoplamento spin-órbita calculada na região de equilíbrio de cada uma das moléculas BeCl, BeBr e BeI foi, respectivamente: 41, 207 e 324 cm-1, em boa concordância com os resultados experimentais: 52,8, 198 e 361,1 cm-1, respectivamente. A separação spin-órbita no limite de dissociação calculada foi de 823, 3446 e 6975 cm-1 (BeCl, BeBr e BeI), também coerentes com resultados experimentais: 882, 3685,24 e 7603,15 cm-1, respectivamente. Foi ainda realizada uma análise detalhada sobre os canais de dissociação das moléculas HBeP e BePH. A construção de um diagrama de energias relativas permitiu obter um conjunto de dados importantes a respeito de todos os possíveis canais de dissociação. Em particular é mostrado a estabilidade relativa e a energia no limite de dissociação. Para a energia no limite de dissociação obtivemos resultados consistentes com os valores experimentais. Nossos cálculos para os três primeiros canais de dissociação HBeP = H + Be resultaram nos seguintes valores: H (2Sg) + Be (X 4Σ+), 0 cm-1; H (2Sg) + Be (a 2π), 426 cm-1 (exp. 502 cm-1); H (2Sg) + Be (b 2Σ-), 1896 cm-1 (exp. 1976 cm-1). Por fim, pela primeira vez na literatura, o calor de formação e de atomização foram calculados para estas espécies. Para os isômeros HBeP e BePH, a energia de atomização a 298,15 K calculada foi de 119,02 kcal·mol-1 e 107,40 kcal·mol-1, respectivamente; para o calor de formação a 298,15 K, obtivemos 86,14 e 97,76 kcal·mol-1 para as espécies HBeP e BePH, respectivamente. / This work has mainly focused on the spectroscopic characterization of the beryllium halides, BeCl, BeBr and BeI. Knowledge about these species was substantially increased through the calculation of parameters that are difficult to access in an experimental characterization. As the few experimental works carried out for these halides presented inconclusive results for the C 2Σ+ - X2Σ+ transition, we carried out accurate calculations of transition probabilities, thus offering a new interpretation about the existing data, including also results for other electronic transitions as yet unknown. Calculations using the method Multireference Configuration Interaction (MRCI) along with correlation-consistent basis set functions of quintuple-zeta quality were used to obtain the potential energy curves associated with the first and second dissociation channels for the doublet and quartet states of these species. Spectroscopic parameters such as vibrational constants We, WeXe, the rotational constant Be and the equilibrium distance were determined for the low-lying states. Furthermore, we also calculated the excitation energy (Te) and the dissociation energy (De) with and without the inclusion of spin-orbit effects. The obtained results significantly expanded our knowledge about the electronic states of this species. For states already investigated experimentally, there was good consistency between the calculated and the experimental parameters. The energy differences between the two channels in the dissociation limit for BeCI, BeBr and Bel molecules obtained in this work were: 21835, 21889 and 21998 cm-1, in agreement with the corresponding experimental results of the three species (21 980 cm-1). The theoretical determination of the dissociation energy D0 was very satisfactory. We obtained 92.24, 72.77, and 51.75 kcal·mol-1, respectively, for the BeCl, BeBr and BeI molecules including spin-orbit effects, compared to 91.78, 71 and 57 kcal . mol-1. For a more complete analysis of the potential energy curves, they also were obtained considering relativistic effects. The calculated spin-orbit coupling constants in the equilibrium region of BeCl, BeBr and BeI molecules were respectively 41, 207 and 324 cm-1, in good agreement with the experimental results: 52.8, 198, and 361.1 cm-1, respectively. The calculated spin-orbit splitting in the dissociation limit was 823, 3446 and 6975 cm-1 (BeCl, BeBr and BeI) also consistent with the experimental results: 882, 3685.24 and 7603.15 cm-1, respectively. Additionally, a detailed analysis of the dissociation channels of HBeP and BePH molecules was performed. The construction of a relative energies diagram allowed us to derive a set of important data for all the possible dissociation channels. In particular, it is shown the relative stability and the energy in the dissociation limit. For the energy in the dissociation limit, we obtained results consistent with the experimental values. Our calculations for the first three dissociation channels HBeP = H + Be resulted in the following values: H (2Sg) + Be (X 4Σ+), 0 cm-1; H (2Sg) + Be (a 2π), 426 cm-1 (exp. 502 cm-1); H (2Sg) + Be (b 2Σ-), 1896 cm-1 (exp. 1976 cm-1). Finally, for the first time in the literature, the heat of formation and the atomization energy were calculated for these species. For the HBeP and BePH isomers, the atomization energy calculated at 298.15 K was 119.02 and 107.40 kcal . mol-1, respectively; for the heat of formation at 298.15 K, we obtained 86.14 and 97.76 kcal· mol-1 for HBeP and BePH species, respectively.

Le travail proposé s’inscrit dans le contexte général de la maîtrise des propriétés des matériaux en relation avec les conditions d’usinage. Cette étude s'intéresse en particulier aux relations entre Microstructure et Usinage. La problématique développée dans ce travail concerne la mise en forme des alliages cuivre-béryllium à usinabilité améliorée (C17300) qui ont la réputation d’être versatiles à l'usinage, en dépit de propriétés mécaniques macroscopiques comparables. La mise en évidence de ces variations d'usinabilité et la recherche des causes et des solutions est l'objectif principal. Après la description du matériau d'étude et des méthodes de caractérisation, l'usinage des alliages C17300 est conduit en réalisant le suivi des efforts et des températures au cours d'une opération de coupe orthogonale stricte. Les résultats expérimentaux, à la fois de la caractérisation multi-échelle et de l'usinage des nuances industrielles dans un état de livraison et de remise en solution, sont présentés. Ils permettent de mettre en œuvre et de valider un modèle analytique de coupe. La question de l'influence de l'usinage sur la microstructure de la pièce usinée est complétée par le développement d'alliages modèles à dureté contrôlée élaborés en interne. Une caractérisation très précise de ces alliages (en surface, en sous-surface et dans les copeaux) permet d’évaluer l’impact de la microstructure initiale sur leur usinabilité. Enfin, une discussion confronte l'ensemble des résultats obtenus. Grâce à l'utilisation du modèle analytique validé, des informations essentielles (temps de contact, temps de transit et température au sein des bandes de cisaillement) permettent de mettre en évidence des phénomènes diffusionnels en cours d'usinage. L'adaptation de différents modèles de diffusion assistée permet d'expliquer les phénomènes observés. Pour clôturer l'étude, de nouveaux chemins de mise en forme des C17300 sont proposés, afin d'assurer l'obtention de propriétés mécaniques excellentes avec une usinabilité améliorée / The document presented hereby study the relationship existing between machining and materials behaviors, especially from a microstructure's perspective. The main purpose of this study is to understand the variability of cutting process of copper-beryllium alloys with improved machining capabilities, despite the fact that their macroscopic mechanical properties are even. After a description of those alloys and the characterization methods used in the present work, the machining of different materials are presented. The stresses and temperatures reached during orthogonal cutting are recorded and will describe the machinability. Experimental results of machining alloys which are in different metallurgical states are then presented. Those results will help the implementation of an analytical model of chips formation. The influence of machining process on work pieces and chips produced by orthogonal cutting of copper-beryllium alloys are then completed by a study of model materials developed in this work. Those alloys presenting well defined microstructure still possess the same hardness despite different thermo-mechanical treatments including mechanical deformation and ageing. A very detailed microstructure analysis of those model materials shows the influence of initial microstructure on their machinability. Diffusion mechanisms are put in light thanks to the information delivered by the analytical model (interaction time, transit time and temperature obtained through the different shear bands). Those assisted diffusion mechanisms explain the material behaviour during the orthogonal cutting. At last, better ways of material forming are exposed in order to have simultaneously excellent mechanical properties and excellent machinability for copper-beryllium alloys

One major step needed for fusion to become a reliable energy source is the development of materials for the extreme conditions (high temperature, radioactivity and erosion) caused by hot plasmas. The main goal of the present study is to use and optimise ion beam methods (lateral resolution and sensitivity) to characterise the distribution of hydrogen isotopes that act as fuel. Materials from the test reactors JET (Joint European Torus), TEXTOR (Tokamak Experiment for Technology Oriented Research) and Tore Supra have been investigated. Deuterium, beryllium and carbon were measured by elastic recoil detection analysis (ERDA) and nuclear reaction analysis (NRA). To ensure high 3D spatial resolution a nuclear microbeam (spot size <10 µm) was used with 3He and 28Si beams. The release of hydrogen caused by the primary ion beam was monitored and accounted for. Large variations in surface (top 10 µm) deuterium concentrations in carbon fibre composites (CFC) from Tore Supra and TEXTOR was found, pointing out the importance of small pits and local fibre structure in understanding fuel retention. At deeper depths into the CFC limiter tiles from Tore Supra, deuterium rich bands were observed confirming the correlation between the internal material structure and fuel storage in the bulk. Sample cross sections from thick deposits on the JET divertor showed elemental distributions that were dominantly laminar although more complex structures also were observed. Depth profiles of this kind elucidate the plasma-wall interaction and material erosion/deposition processes in the reactor vessel. The information gained in this thesis will improve the knowledge of first wall material for the next generation fusion reactors, concerning the fuel retention and the lifetime of the plasma facing materials which is important for safety as well as economical reasons.