Dissertations / Theses: 'Muscoviti'

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LIBERATO. "Stratigraphic, sedimentological and provenance study on the Permian-Triassic sequences of southern Gondwana: comparison between Victoria Land (Antarctica) and Tasmania and paleoenvironmental implications." Doctoral thesis, Università di Siena, 2020. http://hdl.handle.net/11365/1118448.

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La tesi di dottorato è stata svolta seguendo un approccio multidisciplinare che ha riguardato lo studio stratigrafico-sedimentologico, petrografico e geochimico di depositi fluviali Permo-Triassici affioranti in Terra Vittoria meridionale e settentrionale. Con lo scopo di ottenere e comprendere le varie peculiarità di ogni singola unità deposizionale (Permo-Triassica, affiorante ad Allan Hills, Terra Vittoria meridionale), è stato eseguito uno studio di dettaglio multidisciplinare con diverse tecniche e metodologie analitiche. I risultati prodotti sono stati utilizzati per comparare aree limitrofe come il Morris Basin (zona transizionale tra la TVm e TVs), in modo da poter ricostruire l’evoluzione geologico-stratigrafica. I dati sono presentati nella Tesi nell’ordine seguente: 1) comprensione e ricostruzione geologico-stratigrafica dell’area di interesse ad Allan Hills (Terra Vittoria meridionale, TVm, Antartide) 2) analisi sedimentologica (analisi di facies) 3) analisi composizionale delle arenarie di Allan Hills (TVm) e Morris Basin (TVm-TVs, analisi modale con metodo Gazzi-Dickinson) 4) studio dei minerali pesanti presenti in sezione sottile (Allan Hills e Morris Basin, conteggio per clasti) 5) analisi composizionale dei granati e delle muscoviti detritici di Allan Hills (TVm) 6) geocronologia degli zirconi detritici di Allan Hills (TVm) Nella prima parte del dottorato è stato fondamentale reinterpretare ed elaborare circa 800 metri di colonne stratigrafiche ottenute nella fase di campagna dai ricercatori in Antartide, per comprendere i rapporti stratigrafici e la geologia dell’area (punto 1). La sezione geologica del settore nord-est di Allan Hills mostra un andamento degli strati debolmente inclinati verso N-NE (monoclinale) di una decina di gradi. La successione Permo-Triassica affiora in relativa continuità fatta eccezione per aree con diffuse coperture detritiche-nivali e dicchi Giurassici. Il punto 2 è stato acquisito con uno studio ad alta risoluzione (scala decimetrica) eseguendo un’analisi di facies, al fine di ricostruire i paleoambienti della successione di Allan Hills. Seguendo lo schema classificativo ed interpretativo di Miall (2014), più di una decina di litofacies e associazioni di facies sono state interpretate. Il risultato più rilevante sembrerebbe evidenziare fasi trasgressive nel Permiano medio-superiore e nel Triassico medio-superiore, come probabile risposta a cambiamenti morfo-strutturali bacinali dovuti a fattori tettonici e a possibili cambiamenti climatici (come evidenziato nella Formazione Feather Conglomerate). In seguito, a scala microscopica sono state caratterizzate in modo quantitativo le arenarie (punti 3 e 4), al fine di poter individuare differenti petrofacies suddivise per unità formazionali. Differenze rilevanti sono state riscontrate tra le arenarie Permiane e quelle Triassiche; in primis una maggiore maturità composizionale dovuta ad un maggiore trasporto (più cicli di sedimentazione) e ad un clima umido con un weathering index intenso al passaggio PTT (Permian-Triassic Transition). Allo stesso modo, lo studio composizionale del granato e della muscovite (punto 5) sembra evidenziare un maggiore grado metamorfico di provenienza, nel Permiano medio-superiore (Formazione della Weller Coal Measures) e Triassico medio-superiore (Formazione della Lashly), rispetto al Triassico inferiore (Feather Conglomerate). In quest’ultima infatti, le muscoviti sono meno ricche in fengite ed i granati diminuiscono drasticamente (nessun dato composizionale). Questo fenomeno indica probabilmente un repentino cambiamento climatico a favore dell’alterazione. Questo approccio è stato di aiuto nel definire ulteriormente le differenze tra le unità Permiane e Triassiche e le loro provenienze. Con lo stesso scopo, sono state effettuate le datazioni su zirconi detritici di Allan Hills (TVm, punto 6). Tre aspetti fondamentali ne risultano: - nei sedimenti Permiani lo spettro di età è più ampio e si hanno buone percentuali in tutti i range, variabili dal Devoniano all’Archeano. Picchi di età “greenvilliana” sono da evidenziare mentre non sono presenti zirconi Permo-Triassici. - Gli zirconi detritici del Triassico inferiore hanno origine principalmente dall’Orogene di Ross, mostrando forse un unroofing regionale. Con un picco minore, ma pur sempre evidente, ci sono età “greenvilliane”. - Nel Triassico medio-superiore si registra l’attività vulcanica Permo-Triassica del margine meridionale del Gondwana. Sembra evidente come il bacino della Terra Vittoria meridionale fosse, durante il Permiano, morfologicamente separato dal bacino contiguo nelle Central Transantarctic Mountains (CTM). Un processo di cattura fluviale, probabilmente da porsi alla transizione tra il Permiano superiore ed il Triassico inferiore, potrebbe spiegare sia lo spettro composizionale che di età degli zirconi. Una volta ottenuto un quadro completo di ogni singola unità stratigrafica, è stata effettuata una prima comparazione litologico-petrografica con una parte significativa di campioni arenacei sparsi per la Terra Vittoria (Morris Basin e Terra Vittoria settentrionale). Con la missione in Tasmania (febbraio 2019), è stato possibile confrontare in modo preliminare le arenarie delle successioni Tasmane coeve a quelle antartiche. Granulometricamente più fini di quelle del Victoria Group, mostrano rapporti sabbia/fango in alcuni casi confrontabili (dal Triassico inferiore al superiore). Il PTT sembra collocarsi tra superfici di discordanza semplice meno erosivi a sud rispetto al settore nord-nord-est del bacino Tasmano. Questo potrebbe essere attribuito ad una estrema variabilità degli ambienti sedimentari paleozoici e dei processi deposizionali e tettonici. Si rinvengono spessori ingenti di livelli di siltiti argillose rossastre (paleosuoli) con spessori molto variabili. Al contrario, dai dati di questo studio, il PTT ad Allan Hills potrebbe connotarsi per avere caratteri transizionali o di paraconcordanza. Il confronto geologico tra macroregioni diverse e distanti, Terra Vittoria settentrionale e meridionale (TVs TVm), è stato anche rafforzato grazie allo studio analitico di tesi e articoli prodotti negli anni precedenti da altri studiosi. I risultati più importanti provengono dall’analisi di facies e dalle composizioni mineralogiche: - Tutte le petrofacies del Morris Basin sono correlabili con quelle di Allan Hills (TVm) - Una parte dei depositi del Permiano nel bacino della TVs sembra contenere più litici plutonici e metamorfici (circa 5%) rispetto a successioni analoghe ad Allan Hills ed in Terra Vittoria meridionale in generale. - La litostratigrafia di Thern Promontory (TVs) sembra affine, in termini di facies e petrofacies, ad una fase post-glaciale Permiana, come evidenziano alcuni dati in TVm, anche se con spessori notevolmente ridotti. - Le arenarie di Stewart Heights (TVs) e di Pudding Butte (Morris Basin) hanno caratteri sedimentologici e petrologici comparabili con quelle del Triassico inferiore ad Allan Hills (TVm). - Nella Section peak Fm. (simil-Lashly Fm) sono composizionalmente litareniti e litareniti feldspatiche come quelle della SVL. - I bacini della TVs e TVm, in un periodo compreso tra il Triassico medio-Giurassico inferiore, registrano la comparsa di litici vulcanici lavici (Formazioni di Section Peak e Lashly). - Anche per i granati e le miche detritiche triassiche le composizioni sono correlabili tra la TVs e TVm. In conclusione, il presente studio pone nuovi vincoli petro-stratigrafici e paleogeografici in Terra Vittoria meridionale e settentrionale, in quello che era il paleomargine meridionale del Gondwana. In particolare, lo studio sedimentologico e di provenienza dei sopracitati depositi ha consentito di produrre ed apportare una grande mole di nuovi dati, la cui elaborazione consente di evidenziare una storia geologica evolutiva ben più articolata e complessa di quella conosciuta.

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Mayhew, Nick. "Marriage and brotherhood in Muscovite Russia." Thesis, University of Cambridge, 2018. https://www.repository.cam.ac.uk/handle/1810/275349.

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In Russia today, conservative views about gender are often promoted through reference to the past, to show that supposedly ‘traditional’ gender roles are intrinsic to Russian history. Frequently, this idea is upheld in scholarship. My work explores the historicity of commonly held assumptions about gender. This dissertation focusses on gender and sexuality in Russia from the sixteenth to early eighteenth centuries. It shows that ideas about what constituted a virtuous marriage were established by reference to ideas about brotherhood. Brotherhood here refers not to biological siblings, but to a church rite of ‘spiritual brotherhood’ known in Russian as bratotvorenie. This rite has not been studied in any depth before. Based on archival work, this dissertation offers a detailed account of the tradition in Russia until its ban in 1650, when it was prohibited by leading ecclesiastical figures for being too like marriage. One churchman complained: ‘The priest, joining together these two men, unites them in matrimony’. The dissertation shows that bratotvorenie was conceived of in premodern Russia as a form of same-sex union, and that it was through banning this tradition that churchmen came to express in a coherent way which kinds of partnership were legitimate and why. The first chapter challenges the idea that marriage was always a monogamous union between a man and a woman for the creation of children, an idea that is often encountered in academic literature on Russian marriage history. It shows that the church rite of marriage was edited in Russia during the sixteenth and seventeenth centuries, when ideas about the sacramental nature of marriage changed. The second chapter builds on these observations, suggesting that marriage and ‘spiritual brotherhood’ were understood as analogous in the premodern period. The final two chapters look at depictions of marriage and brotherhood in hagiography and iconography respectively. They focus on Petr and Fevroniia, the first married couple to be canonised in Russia in 1547. In 2008, their feast day was reworked into a state festival called the ‘Day of Family, Love and Fidelity’, now widely celebrated across Russia. Petr and Fevroniia have been cast as the patron saints of so-called ‘traditional moral-spiritual values’. This view is generally upheld in existent scholarship on the saints. This dissertation responds to the way the saints are being represented today, arguing that they were initially venerated for subverting normative ideas about gender and sexuality—that they were queer. What is more, their veneration paralleled the veneration of holy brothers. Their hagiography seems to have been based on the Life of a monastic brotherhood, and icons depicting Petr and Fevroniia standardly showed them in monastic robes. Focussing on marriage and brotherhood in premodern Russia, each chapter of this dissertation challenges a preconceived idea about the immutability of supposedly ‘traditional’ gender roles in Russian history.

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Lixandrão, Filho Arnaldo Luis 1983. "Estudos de "annealing" de traços de íons e traços de fissão em muscovita." [s.n.], 2016. http://repositorio.unicamp.br/jspui/handle/REPOSIP/330569.

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Orientador: Sandro Guedes de Oliveira
Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Física Gleb Wataghin
Made available in DSpace on 2018-08-31T19:22:36Z (GMT). No. of bitstreams: 1 LixandraoFilho_ArnaldoLuis_M.pdf: 11489211 bytes, checksum: 0e5e2fdcd3551b722c60d418964284ee (MD5) Previous issue date: 2016
Resumo: O trabalho consistiu em estudar a muscovita como termocronômetro. Por ter pequena quantidade de urânio, abaixo de 5 partes por milhão, a utilização direta é inviável. Dessa forma, irradiamos placas de muscovita com íons de $^{238}U$ moderados por folhas de alumínio (resultando em diferentes energias) e com diferentes ângulos de incidência, com a finalidade de analisar o comportamento da muscovita com traços de íons e também para que esses íons criassem canais com o objetivo de revelar maior quantidade de traços fósseis. Realizamos planejamento utilizando algorítimo D-ótimo para realizar tratamentos térmicos com diferentes tempos e temperaturas, a fim de obter dados de ''annealing'' para a muscovita. Medimos o comprimento dos traços de íons projetados com as seguintes dependências: massa do íon, tempo de ''annealing'', temperatura de ''annealing'', energia de incidência e ângulo de incidência. Os parâmetros energia de incidência, ângulo de incidência e características do íon, não são considerados em nenhum dos modelos disponíveis na literatura. Assim sendo, formulamos um novo modelo empírico para a cinética de ''annealing'': $l = l_0 + a*energia - e^{\left(\frac{temperatura}{b + c*log(tempo)}\right)}$, $l$ sendo comprimento do traço com ''annealing'' e $l_0$ o comprimento sem ''annealing'' e, as constantes $a$, $b$ e $c$ ajustadas a partir dos dados experimentais. As constantes $a$ e $L_0$ são as variáveis relativas ao ângulo de incidência, tipo do íon e energia. Este modelo, além de ter um número menor de parâmetros, com uma simples modificação, $\frac{L}{L_0} = 1 + A.e^{\frac{T}{b}},\ b = B+C.ln(t)$, pode ser aplicado também para traços de fissão confinados. Nesse caso são apenas 3 parâmetros, $A$, $B$ e $C$ e o modelo ajustado possibilita a análise térmica em qualquer mineral que possuir dados experimentais. Neste trabalho mostramos o ajuste para os seguintes minerais: apatita, zircão, epídoto e muscovita. A partir dos traços de íons que sofreram ''annealing'' conseguimos ajustar parâmetros e obtivemos resultados consistentes com trabalhos anteriores. Um deles foi a previsão de \citeauthor{Bigazzi1967} que, possivelmente, utilizou amostras de superfície à 303K. Com esse resultado, validamos que traços de íons podem gerar bons resultados no estudo de ''annealing'' em laboratório e em tempos geológicos. Por fim, desenvolvemos um aplicativo que contempla: o ajuste dos parâmetros do modelo aos dados experimentais de modo automático, a obtenção de índices térmicos (temperatura de fechamento e zona de ''annealing parcial'') independente do mineral e a reconstrução de histórias térmicas para múltiplos minerais a partir de vínculos geológicos, da idade e de uma lista de comprimento de traços confinados. Além dessas características, a inédita ferramenta utiliza interface ''web'' que pode ser utilizada em qualquer plataforma e sistema operacional. Por fim, os resultados significativos foram: novos dados de ''annealing'' de traços de íons em mica muscovita, novo modelo empírico para abordar a cinética do ''annealing'' para traços de íons ou fissão e um aplicativo para tratamento de dados, ajuste, obtenção de índices térmicos e histórias térmicas
Abstract: In this work we studied muscovite as a thermocronometer. Muscovite have low amount of uranium, below 5 parts per million. Because of that it is impractical to be used as thermocronometer. Thus irradiating it with swift heavy ions of $ ^ {238} U $, moderated by aluminum foil (resulting in different energies) and with different angles of incidence is one way to analyze the behavior of muscovite ion tracks. These tracks can act like channels to the acid, chemical etching, revealing more fossil traces. We carry out experimental planning using D-optimal algorithm do thermal treatments at different times and temperatures in order anneal muscovite tracks. We measured the length of the ion tracks created with the following dependencies: ion mass, annealing time and temperature, impact energy and angle of incidence. The incidence of energy parameters, angle of incidence and ion characteristics are not considered in any of the models available in the literature. Therefore, we have developed a new empirical model for the kinetics of annealing: $l = l_0 + a*energia - e^{\left(\frac{temperatura}{b + c*log(tempo)}\right)}$, $l$ annealed fission track length and $l_0$ fission track length and the constants $a$, $b$ and $c$ adjusted from the experimental data . The constants $a$ and $L_0$ are related to the angle of incidence, type of ion and energy. This model, besides having fewer parameters, with a simple modification, $\frac{L}{L_0} = 1 + A.e^{\frac{T}{b}},\ b = B+C.ln(t)$ may also be applied to confined fission tracks. The adjusted model , with only 3 parameters, $A$, $B$ and $C$, enables thermal analysis in any mineral that has experimental data. We show fitting for the following minerals: apatite, zircon, epidote and muscovite. From the annealed ion tracks we fit the data to get all parameters and obtained results consistent with previous work. One was that we predict that \citeauthor{Bigazzi1967}, possibly, used surface samples with 303 K. With this result, we validate that ions tracks can generate good results using annealing laboratory data extrapolated to geological time. Finally, we developed an application with the following features: automatic model fitting to experimental data, simulation of thermal index (closure temperature and partial annealing) independent of the mineral and the reconstruction of thermal histories for multiple minerals from geological. In addition to these features, the application has web interface and can be used on any platform and operating system. Finally, the most significant results of this work were: new experimental annealing data of ion tracks in muscovite, new empirical model to increase the knowledge of the ion or fission tracks annealing kinetics and an application for data processing, fit and simulation of thermal index and thermal histories reconstruction
Mestrado
Física
Mestre em Física

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Davis, Laura E. "Pegmatitic muscovites: effect of composition on optical and lattice parameters." Thesis, Virginia Polytechnic Institute and State University, 1985. http://hdl.handle.net/10919/50066.

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Twenty-five muscovites have been systematically studied chemically, optically, and structurally. Multiple linear regressions were performed on these data to determine the correlations of the compositional components with both the optical properties and the unit cell parameters. The results of this study indicate refractive indices increase to the extent Fe and Ti constitute the octahedral cations, and to the extent OH rather than F coordinates to these cations. The optic angle 2VX decreases nearly linearly with the Ti content. The b cell edge follows a near-linear trend with ∑(Mg + Fe(total)), similar to that found by Guidotti (1984).
Master of Science
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Zhukova, Tatyana Alexandra. "The gift-giving culture of Anglo-Muscovite diplomacy, 1566-1623." Thesis, University of Nottingham, 2018. http://eprints.nottingham.ac.uk/55471/.

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In 1589, the government of Tsar Feodor I of Muscovy returned the gift of golden medals received from Queen Elizabeth I, describing the offending objects as neither commendable nor agreeable. The rejection was accompanied with opprobrious public speeches about the gift's unsuitability and a threat to transfer Muscovite favour unto other European nations if Elizabeth offered no immediate redress. In her defence, Elizabeth argued that diplomatic gifts were to be accepted not in respect of the object itself, but of the royal majesty from whom it was presented. While the episode appears to show a petty squabble over material trinkets, its diplomatic repercussions were significant as the following five years would be dedicated to the repair of Anglo-Muscovite relations. Clearly, gifts were integral to the mechanics of early modern diplomacy. This thesis explores an intriguing, but as yet scarcely studied, facet of diplomatic history: the operation of Muscovite diplomacy prior to the reign of Peter the Great. It focuses on Muscovy's long-term relations with England (Muscovy's first continual diplomatic relationship with a Western European power in the sixteenth century) and examines the exchange of sovereign gifts between the two royal courts. The principal novelty of this research lies in its departure from the anthropological definition of the gift as a 'material' object, instead it argues that non-tangible components, such as royal favours, were also 'gifts', provided they were given willingly, were reciprocated− if not necessarily symmetrically, and created emotional, political and social bonds between the participants. As an example of such intangible gift, this thesis uses the Muscovite zhalovannaia gramota (a charter of mercantile privileges). In this way, the research explores the full range and complexity of diplomatic gift-exchange between the two monarchies in a crucial period of dynastic change in both countries. Frequently, gift-giving is interpreted as either a means of intercultural communication par excellence or, in the case of a rejected gift, as evidence of an inevitable clash of cultures. This thesis, however, demonstrates that diplomatic gift-exchange was a multi-faceted process. Royal intentions were complex and, therefore, required different levels of engagement; their transmission was reliant upon intermediaries (ambassadors), and the reception of gifts was intrinsically linked to diplomatic aims. Secondly, in contrast to the widespread assumption that the diplomatic cultures of England and Muscovy were discordant, day-to-day diplomatic exchanges (including gift-giving) drew the Tsars into a shared ceremonial arena, where other rulers competed for the symbolic resources of sovereignty. The exchange of gifts between the two states facilitated the process of gradual integration of the apparently alien Muscovite Tsar into the English (and essentially European) standardised codes of diplomatic behaviour and ceremonial communication. It was not until the reign of Peter I, however, that the Tsars fully became prominent members of the European society of princes. Diplomatic practice was neither universal nor culturally specific; such assumptions are obstructive to a better understanding of the mechanics of cross-cultural interactions. Ultimately, diplomatic ceremony and gift-giving were driven by notions of sovereign honour and the symbolic language of the court society, and not by political, national or cultural incommensurability. Thus, the foundations of Muscovy's gradual integration into European codes of diplomatic behaviour can be traced to the reign of Ivan IV, and specifically, to the continuous Muscovite diplomatic relationship with the English Crown.

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Tshering, Peldon. "Detrital muscovite thermochronology in two drainage basins in western Bhutan." Thesis, Massachusetts Institute of Technology, 2007. http://hdl.handle.net/1721.1/39008.

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Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Earth, Atmospheric, and Planetary Sciences, 2007.
Includes bibliographical references (leaves [34]-38).
New reconnaissance data for a poorly characterized area in the western Bhutan Himalaya show distinction between the 40Ar/39Ar cooling age distributions of detrital minerals in the two river catchments of the Punatsang chu and the Wang chu. Muscovites from five samples of Wang chu river sands yield ages (corresponding roughly to the time of bedrock cooling through a temperature of ca.350°C) between 9.37± 0.08 Ma and 13.98 ± 0.08 Ma. The majority of ages are less than 13 Ma, and the data for all samples have a unimodal distribution with an average age of ca. 11.4 ± 1.5 Ma. In contrast, muscovites from 14 Punatsang chu samples yield ages with nearly the same total range but with a distinctively multi-modal distribution. Two modes predominate in the Punatsang chu data: one at ca. 11.4 Ma, which is statistically indistinguishable from the single mode of the Wang chu data, and one at ca. 14.5 Ma. The full explanation for this distribution must await further bedrock and detrital dating studies, but one hypothesis is that the out-of-sequence Kakhtang thrust fault system - which is thought to transect the upper reaches of the river catchments - has juxtaposed two bedrock terrains with different cooling histories.
(cont.) A second possibility is that the younger mode of cooling ages is related to uplift of the footwall of the Chomolhari fault system, which includes the major bounding structures of the Yadong-Gulu rift northwest of the catchments. Exactly why the older mode of ages is not found in the Wang chu dataset is unclear. If the first of the above hypotheses is correct, the lack of an older mode in the Wang chu dataset may mean that the muscovites in the Wang chu fluvial sediments were derived exclusively from the Kakhtang thrust system hanging wall. If the second hypothesis is correct, the muscovites may have been derived exclusively from the Chomolhari fault system footwall. However, since we do not know the actual distribution of muscovites in the Wang chu catchment and we do not know that modern erosion is uniform in the catchment, it is also possible that the older mode is simply missing as an artifact not-uniform sampling. Again, more studies are needed to evaluate these alternative explanations.
by Peldon Tshering.
S.M.

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Gridi-Bennadji, Fayza. "Matériaux de mullite à microstructure organisée composés d'assemblage muscovite-kaolinite." Limoges, 2007. https://aurore.unilim.fr/theses/nxfile/default/0475a8c9-501a-4ac2-bdac-9d95eeaa3b66/blobholder:0/2007LIMO4033.pdf.

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Des matériaux de mullite à microstructure organisée sont réalisés à partir d'assemblages des minéraux muscovite et kaolinite. L'étude par diffraction Rx et de neutrons de la muscovite montre l'effet de la température sur la réduction de l'organisation structurale, alors que l'arrangement en feuillets et l'alignement préférentiel des unités structurales dans les 3 directions de cristallisation sont maintenus jusqu'à 1095°C. La croissance organisée de grands cristaux de mullite est favorisée par un phénomène d'épitaxie. L'étude de la cinétique des transformations thermiques et du processus d'exfoliation de la muscovite ainsi que du cycle de frittage permettent d'obtenir des substrats de 500µm d'épaisseur. Les corrélations entre la microstructure et les propriétés mécaniques montrent la possibilité d'obtention de matériaux dont la résistance mécanique et la ténacité sont élevées en comparaison de celles des matériaux de composition similaire
Micro-composite materials with an organized microstructure with mullite are formed from assemblages of muscovite and kaolinite minerals. Rx diffraction and neutron studies of muscovite point to the temperature effect on the reduction of the structural organization, while sheet arrangements and preferential orientations of structural units in the 3 directions of mullite crystals are maintained up to 1095°C. These behaviors favor the organized growth of large mullite crystals by epitaxy on the high-temperature form of muscovite. The study of the kinetics of thermal transformations and of the exfoliation process of muscovite leads to the optimization of the sintering process of substrates with a thickness of 500µm. The study of correlations between microstructure and mechanical properties leads to the optimization of materials with a higher strength and fracture toughness, in comparison with the behavior of similar materials

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Nana, Koumtoudji Lecomte Gisèle Laure. "Transformations thermiques, organisation structurale et frittage des composés kaolinite-muscovite." Limoges, 2004. http://aurore.unilim.fr/theses/nxfile/default/1f887c04-ebcd-4780-a15c-aee018af90f2/blobholder:0/2004LIMO0034.pdf.

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Les argiles les plus utilisées pour l'élaboration des céramiques de grande diffusion ont des teneurs élevées en minéraux du groupe de la kaolinite et des micas. Pour étudier les propriétés d'usage de ces argiles dans les matériaux céramiques, nous avons analysé les transformations thermiques et structurales ainsi que le processus frittage de composés kaolinite-muscovite. Leurs teneurs en muscovite sont inférieures à 25% de la masse totale. Le comportement idéal des composés s'insère dans le diagramme ternaire Al2O3-SiO2-K2O, dans une zone non étudiée. Nous proposons une étude expérimentale et une modélisation de deux sections verticales de ce diagramme, qui décrivent les composés kaolinite-muscovite. Il est ainsi montré l'existence d'un domaine d'immiscibilité sur la section reliant le point eutectique à 985°C au point de composition de la mullite, susceptible d'être le prolongement dans le ternaire de la lacune de miscibilité mise en évidence autour du point de composition de la kaolinite dans le diagramme binaire Al2O3-SiO2. Le comportement global est aussi caractérisé par l'analyse des transformations thermiques. On observe notamment que jusqu'à 900°C, la kaolinite et la muscovite évoluent sans interaction. Dès 925°C, la diffusion du potassium a pour effet de modifier les processus de réorganisation structurale de la métakaolinite. Le phénomène exothermique à 980°C s'en trouve fortement diminuer. Vers 1140°C le pic caractéristique de la réaction péritectique reste invariable et proportionnel à la quantité de muscovite réagissante, tandis que l'épaulement exothermique lié à cristallisation de la cristobalite et de la mullite secondaire est décalé vers les basses températures en présence de muscovite. La croissance de la mullite à l'interface kaolinite-muscovite a été étudiée par diffraction des rayons X et par l'analyse des fonctions de distribution de paires atomiques. Les résultats montrent des orientations systématiques des cristallites de mullite, suivant les directions (010), (310) et () de la muscovite. La croissance préférentielle de la mullite à l'interface des minéraux a pu être expliquée par une relation d'épitaxie entre les phases haute température des phyllosilicates. L'utilisation des modèles de frittage existant dans la littérature se heurte à la complexité des transformations des composés de phyllosilicates et de leurs morphologies particulières. Néanmoins, nous montrons l'existence de trois mécanismes principaux qui contrôlent la densification des composés : le frittage par flux visqueux, le frittage par diffusion aux joints de grains et le frittage avec phase liquide. Cette étude a permis de mettre en évidence les interactions mutuelles entre les minéraux kaolinite et muscovite. Les transformations structurales et microstructurales qui résultent de traitements thermiques appropriés doivent permettre de réaliser des matériaux céramiques dont la microstructure est organisée. Nous avons aussi contribué à la compréhension des mécanismes de frittage de mélanges complexes de phyllosilicates. L'apport de ces résultats est favorable à l'industrie céramique, notamment en ce qui concerne la production des matériaux de grande diffusion

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9

Gruber, Isaiah. "The Muscovite embassy of 1599 to Emperor Rudolf II of Habsburg." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape9/PQDD_0022/MQ50518.pdf.

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10

Roland, Patrick. "Contribution à l'étude du broyage des amiantes et du mica muscovite." Mulhouse, 1986. http://www.theses.fr/1986MULH0014.

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Etude de l'influence du milieu liquide dans lequel est opéré le broyage (aqueux ou organique). Dans le cas de la muscovite, au comportement beaucoup plus complexe que celui de l'amiante, on met en évidence l'influence non seulement du milieu liquide mais aussi de la présence d'ions ou d'autres réactifs ajoutés en faibles quantités. L'ensemble des résultats s'explique en postulant l'existence d'un film d'eau aux propriétés particulières, en surface, des minéraux étudiés

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11

Roland, Patrick. "Contribution à l'étude du broyage des amiantes et du mica muscovite." Grenoble 2 : ANRT, 1986. http://catalogue.bnf.fr/ark:/12148/cb37600749n.

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12

McDonald, Wayne M. Hames W. "⁴⁰Ar/³⁹Ar ages of muscovite from the western Blue Ridge and Talladega belt, Georgia and North Carolina." Auburn, Ala, 2008. http://repo.lib.auburn.edu/EtdRoot/2008/SPRING/Geology_and_Geography/Thesis/Mcdonald_Wayne_42.pdf.

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13

Blajan, Marius Gabriel. "Séparation du muscovite des pegmatites feldspathiques en utlisant des champs électriques intenses." Poitiers, 2006. http://www.theses.fr/2006POIT2326.

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L’objectif a été d’utiliser les forces du champ électrique pour concentrer le muscovite présent dans les résidus issus de la préparation des pegmatites feldspathiques. Les processus de charge électrique en milieu ionisé des minéraux granulaires et de leur décharge en contact avec une électrode sont étudiés dans des conditions modélisant celles des installations industrielles. Le comportement des dispositifs de charge triboélectrique conçus par le doctorant est modélisé avec la méthode des plans d’expériences. L’étude montre que les différences de conductivité électrique ou de charge triboélectrique entre les constituants des pegmatites suffisent pour les séparer respectivement dans des installations électrostatiques à tambour ou à chute libre. Les séparateurs à champ couronne et à électrode cylindrique tournante présentent un avantage important : la multitude des variables de contrôle. Les essais réalisés sur un séparateur pilote-industriel confirment l’intérêt de cette solution
The aim of the thesis is to analyse the possibility of using electric field forces for the concentration of muscovite from the residual materials of pegmatite beneficiation technologies. The literature survey presented in the first chapter points out the peculiarities of the involved minerals and the characteristics of the characteristics of the high-intensity electric field installations that could be employed for their selective sorting. Charge and discharge processes of granular minerals are studied in conditions similar to those of industrial electrostatic separators. Design of experiments methodology is employed for the study of an original tribo-charging device, which can be used in association with free-fall electrostatic separators for the concentration of muscovite. Conductivity difference between the constituents of pegmatite is enough for an efficient separation in roll-type corona or corona- electrostatic separators. Pilot-plant tests have confirmed this solution

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14

DOREL, Sébastien. ". Nanostructuration de la muscovite : Une étude par diffraction d'électrons lents en mode oscillant." Phd thesis, Université Paris Sud - Paris XI, 2000. http://tel.archives-ouvertes.fr/tel-00002738.

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Nous avons étudié la structure de la surface de mica muscovite clivée à l?air par diffraction d?électrons lents en mode oscillant. Cette nouvelle méthode d?analyse structurale, que nous avons développée à partir d?un système optique standard de résolution conventionnelle, possède une grande sensibilité. En outre, elle permet de former des images de diffraction entières sans procéder, comme le font les autres diffractomètres à haute résolution, à une reconstitution ligne par ligne. Cette caractéristique permet aussi de réaliser des acquisitions d?image qui sont corrélées temporellement avec une excitation extérieure, ce qui rend possible toute une gamme d?expériences nouvelles, notamment dans le cadre de la réponse thermodynamique d?une surface au voisinage d?une transition de phase. Notre étude de la surface du mica muscovite par diffraction d?électrons lents en mode oscillant a permis pour la première fois de mettre en évidence la nanostructuration de sa couche superficielle. Notre interprétation est que lors du clivage, la surface du mica s?auto-organise pour former un arrangement d?îlots à l?intérieur desquels les atomes de potassium occupent les sites réguliers du cristal. Les îlots sont soit de taille définie soit séparés par une distance définie. Dans les zones interstitielles qui les séparent, les ions potassium, en concentration beaucoup plus faible, formeraient une couche amorphe.

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15

DOREL, SEBASTIEN. "Nanostructuration de la muscovite : une etude par diffraction d'electrons lents en mode oscillant." Paris 11, 2000. http://www.theses.fr/2000PA112121.

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Nous avons etudie la structure de la surface de mica muscovite clivee a l'air par diffraction d'electrons lents en mode oscillant. Cette nouvelle methode d'analyse structurale, que nous avons developpee a partir d'un systeme optique standard de resolution conventionnelle, possede une grande sensibilite. En outre, elle permet de former des images de diffraction entieres sans proceder, comme le font les autres diffractometres a haute resolution, a une reconstitution ligne par ligne. Cette caracteristique permet aussi de realiser des acquisitions d'image qui soient correlees temporellement avec une excitation exterieure, ce qui rend possible toute une gamme d'experiences nouvelles, notamment dans le cadre de la reponse thermodynamique d'une surface au voisinage d'une transition de phase. Notre etude de la surface du mica muscovite par diffraction d'electrons lents en mode oscillant a permis pour la premiere fois de mettre en evidence la nanostructuration de sa couche superficielle. Notre interpretation est que lors du clivage, la surface du mica s'auto-organise pour former un arrangement d'ilots a l'interieur desquels les atomes de potassium occupent les sites reguliers du cristal. Les ilots sont soit de taille definie soit separes par une distance definie. Dans les zones interstitielles qui les separent, les ions potassium, en concentration beaucoup plus faible, formeraient une couche amorphe.

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16

Pachana, Katavut. "Nanogéochimie : mécanismes d'altération des micas à l'échelle moléculaire : (apport de la Microscopie à Force Atomique)." Paris 7, 2004. http://www.theses.fr/2004PA077134.

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17

Benoit, Alexandre. "Ivan IV et la consolidation du pouvoir muscovite dans l'historiographie russe du XIXe siècle." Thesis, McGill University, 2013. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=114533.

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Tsar Ivan IV, commonly known as Ivan the Terrible, rapidly became a symbol of Russian national identity. From the creation of the Russian Empire by Peter the Great, Ivan became recognized as the leader who consolidated Muscovite territory in the 16th Century and centralised his power against the whims of an elite which sought to preserve their privileges. However, the construction of this historical narrative was a long process, limited by the paucity of the sources as well as certain state conventions. This thesis aims to analyse how the four key historians of the Russian Empire assembled historical knowledge on Ivan IV. The writings of Nikolai Karamzin, Sergei Soloviev, Vasilii Kliuchevskii and Sergei Platonov are examined in order to understand the process that forged historiographical knowledge on the second part of Ivan's reign, which was characterised by the cruelty as well as the consolidation of his power. This analysis outlines the influence that personal experiences, beliefs and socio-political context had on the way these historians interpreted this period, which was crucial to the emergence of the modern Russia state.
Le tsar Ivan IV, surnommé le Terrible, fut un personnage qui devint rapidement un symbole pour l'identité nationale russe. Dès la création de l'Empire russe par Pierre le Grand, il fut reconnu comme celui qui a consolidé le territoire de la Moscovie au XVIe siècle et a centralisé son pouvoir contre les velléités d'une élite à conserver ses privilèges. Cependant, la construction de ce récit historique fut un long procédé, limité par la rareté des sources et les conventions étatiques. Cette thèse visait à analyser comment quatre historiens clés de la Russie impériale construisirent les connaissances historiques sur Ivan. Les écrits de Nikolai Karamzin, Sergei Soloviev, Vasilii Kliuchevskii et Sergei Platonov seront pris en compte pour comprendre le processus derrière l'historiographie de la seconde partie du règne d'Ivan, caractérisée par une cruauté et par la consolidation de son pouvoir. Cette analyse démontre l'influence que les expériences personnelles de l'historien, ses croyances et le contexte socio-politique sur la construction de cette période jugée capitale pour l'État russe.

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18

Runyon, Simone E., Matthew Steele-MacInnis, Eric Seedorff, Pilar Lecumberri-Sanchez, and Frank K. Mazdab. "Coarse muscovite veins and alteration deep in the Yerington batholith, Nevada: insights into fluid exsolution in the roots of porphyry copper systems." SPRINGER, 2017. http://hdl.handle.net/10150/623613.

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Veins and pervasive wall-rock alteration composed of coarse muscovite +/- quartz +/- pyrite are documented for the first time in a porphyritic granite at Luhr Hill in the Yerington District, Nevada. Coarse muscovite at Luhr Hill occurs at paleodepths of similar to 6-7 km in the roots of a porphyry copper system and crops out on the scale of tens to hundreds of meters, surrounded by rock that is unaltered or variably altered to sodic-calcic assemblages. Coarse muscovite veins exhibit a consistent orientation, subvertical and N-S striking, which structurally restores to subhorizontal at the time of formation. Along strike, coarse muscovite veins swell from distal, millimeter-thick muscovite-only veinlets to proximal, centimeter-thick quartz-sulfide-bearing muscovite veins. Crosscutting relationships between coarse muscovite veins, pegmatite dikes, and sodic-calcic veins indicate that muscovite veins are late-stage magmatic-hydrothermal features predating final solidification of the Luhr Hill porphyritic granite. Fluid inclusions in the muscovite-quartz veins are high-density aqueous inclusions of similar to 3-9 wt% NaCl eq. and < 1 mol% CO2 that homogenize between similar to 150 and 200 A degrees C, similar to fluid inclusions from greisen veins in Sn-W-Mo vein systems. Our results indicate that muscovite-forming fluids at Luhr Hill were mildly acidic, of low to moderate salinity and sulfur content and low CO2 content, and that muscovite in deep veins and alteration differs in texture, composition, and process of formation from sericite at shallower levels of the hydrothermal system. Although the definition of greisen is controversial, we suggest that coarse muscovite alteration is more similar to alteration in greisen-type Sn-W-Mo districts worldwide than to sericitic alteration at higher levels of porphyry copper systems. The fluids that form coarse muscovite veins and alteration in the roots of porphyry copper systems are distinct from fluids that formed copper ore or widespread, shallower, acidic alteration. We propose that this style of veins and alteration at Luhr Hill represents degassing of moderate volumes of overpressured hydrothermal fluid during late crystallization of deep levels of the Yerington batholith.

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19

Romaniello, Matthew Paul. "Conquest, Colonization and Orthodoxy : Muscovy and Kazan', 1552-1682." Connect to resource, 1998. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1142004291.

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20

Myles, John Eric. "The Muscovite ruling oligarchy of 1547-1564 : its composition, political behaviour and attitudes towards reform." Thesis, University of Oxford, 1988. http://ora.ox.ac.uk/objects/uuid:fa3000e9-f181-45de-9600-4352f58a02a6.

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In recent decades considerable progress has been made in elucidating the assumptions and the dynamics of Muscovite court politics, and further scrutiny is attempted in this enquiry into the ruling oligarchy of 1547-1564. Chapters 1 to 3 are devoted to groundwork. In Chapter 1 an introduction to the ruling oligarchy is provided against the background of Muscovy's contemporary government and population. The goal of territorial aggrandisement pursued by Muscovite rulers from Ivan HI favoured "rationalisation" of the central government and reforms of the army's discipline and technology; moreover, the wars of conquest left untouched no element of the population. Tsar Ivan and his exercise of authority were especially strongly affected: the precedents established by earlier rulers encouraged him to consider Muscovy his private votchina. but such an attitude became increasingly anachronistic as the realms expanded and the tasks of governing it grew too complex for any one man. During the Oprichnina he attempted to resolve this contradiction by ruling autocratically; autocratic rule and those circumstances favouring it by 1564 are the dissertation's main theme. Even before 1564 Ivan IV was the central actor in Muscovite politics, and criteria are advanced whereby advisers close enough to qualify for the ruling oligarchy are identified. The mid-sixteenth century, as a prelude to autocracy, was a critical moment in Muscovite politics; the rich and varied historiography is surveyed in Chapter 2. The sources - their authors, dates, and value as historical evidence - are critically assessed in Chapter 3. Chapter 4 to 7 comprise the heart of the dissertation. In Chapters 4 to 6 an attempt is made to identify members of the ruling oligarchy of 1546-1564; their political behaviour and where feasible, their political attitudes are explored. In Chapter 7 the attitudes individual members maintained towards particular reforms envisaged at mid-century are explored. The dissertation's main conclusions are systematically expounded in Chapter 8, and as appropriate, their broader implications for Russian and European history are brought out.

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21

Binda, Nathalie. "Modification de surface du mica muscovite en vue de son incorporation dans une matrice polypropylène." Montpellier 2, 1994. http://www.theses.fr/1994MON20034.

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L'objet de cette etude est la modification de surface du mica muscovite afin d'ameliorer sa compatibilite avec une matrice polypropylene. Plusieurs modifications de surface ont ete realisees sur ce solide naturel. Elles rassemblent : - l'activation chimique et thermique du mica prealables a une fonctionnalisation avec un compose bifonctionnel de type silane, - la fonctionnalisation de la charge non activee par le compose de type silane, par un agent de flottation ou par la combinaison de ces deux agent. Ces divers traitements de surface se sont traduits par des evolutions de proprietes mecaniques du materiau final. Mais la fonctionnalisation de la charge non activee par des agents de type silane ou des agents de flottation s'avere la methode la plus appropriee pour comptabiliser la charge avec la matrice organique. De plus, l'association de l'agent de couplage avec l'agent de flottation comme traitement de surface du mica nous a permis, grace a la complementarite des effets des deux produits d'obtenir un materiau performant sur l'ensemble des proprietes mecaniques et thermiques.

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22

Dyck, Brendan. "Textural and petrological studies of anatexis and melt transfer in the Himalayan Orogen." Thesis, University of Oxford, 2016. https://ora.ox.ac.uk/objects/uuid:98cc1d84-d552-447d-a54a-0f028eecf0f7.

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Mineral textures, preserved in the metamorphosed sedimentary sequences that are exposed in orogenic hinterlands, are crucial to understanding the architecture and evolution of collisional mountain belts. In this thesis the textural record of anatexis and melt transfer in the Himalayan metamorphic core is decoded and the controls that these processes exert on the tectonic evolution of the Himalaya are explored. The problem is divided into two parts, corresponding to variations in protolith lithostratigraphy: melt source - the pelitic region where melt was first generated, and melt sink - the psammitic region where melt accumulated and crystallised. Dehydration melting of muscovite has long been recognized as a critical reaction for the generation of anatectic melt in the Himalaya, but a textural understanding of how this reaction progresses is limited by the inherent difficulties in identifying specific reaction products. Using samples collected from the Langtang area in central Nepal, a mechanistic model for muscovite dehydration melting was constructed, and a set of textural criteria were developed, which were used to distinguish peritectic K-feldspar from K-feldspar grains formed during melt crystallisation. Melt is transferred from the source to the sink in two stages: firstly along a pervasive network of mineral grain boundaries, and secondly via a channelised network of sills and dykes in the melt sink where it solidified as leucogranite. Variation in the primary mineral assemblage and appearance of leucogranite bodies reflect the degree of interaction that occurred between the melt and metasedimentary country rock, rather than a change in primary melt composition. The modal proportion of K-feldspar in the melt source requires vapour-absent conditions during muscovite dehydration melting and leucogranite formation, indicating that the generation of large volumes of granitic melts in orogenic belts is not necessarily contingent on an external source of fluids. The crystallisation of hydrous minerals in leucogranite consumes <15.5 % of water released by the breakdown of muscovite. These results indicate that anatexis efficiently dehydrates the middle crust and suggests that the continents have limited potential to store water over geological time.

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23

Gassman, Paul Lawrence. "The influence of particle size on the chemistry of mica clays." Thesis, Virginia Tech, 1990. http://hdl.handle.net/10919/42081.

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In order to assess the importance of particle size on elemental composition, structure, morphology, and charge characteristics of 2:1 micas, mechanically produced clay separates were analyzed by; electron probe microanalysis (EPMA), transmission electron microscopy (TEM), thermogravimetry, specific surface area analysis, and ion exchange. Books of biotite and muscovite were reduced to clay size Â« 2.0 Î¼m) particles by mechanical comminution, then further fractionated into coarse (0.2-2.0 Î¼m), medium (0.08-0.2 Î¼m), and fine (< 0.08 Î¼m) clay sizes. Composition of the clay size micas was particle size dependent, compositional changes being smaller for the medium and coarse clays. Grinding produced significant losses of interlayer K, decreased crystallinity, but increased water content as particle size decreased.

The medium and coarse clays maintained coherent basal diffractions, whereas, significant peak broadening of x-ray diffraction maxima was observed for the fine clays. Diffracted peak broadening was due to the reduced crystallite size and the semirandom orientation of lath shaped particles.

Specific surface area, adsorbed water. and structurally coordinated water increased as particle size decreased. Specific surface areas were determined by adsorption of molecular nitrogen, at liquid nitrogen temperatures. The increased water contents were measured by thermogravimetric analysis.

An increase in CEC of the muscovite clays was detected with decreasing particle size, increasing solution pH, and increasing ionic strength. Assignment of specific exchange capacities for the three clays was confounded by AI hydrolysis and depressed solution pH.

Master of Science

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24

Das, David Hari. "History writing and late Muscovite court culture : a study of Andrei Lyzlov's History of the Scythians /." Thesis, Connect to this title online; UW restricted, 1991. http://hdl.handle.net/1773/10509.

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Viana, Paulo Roberto de Magalhaes. "Flotação de espodumênio, microclina, quartzo e muscovita com coletores aniônicos, catiônicos, anfotéricos e mistura de coletores." Universidade Federal de Minas Gerais, 2006. http://hdl.handle.net/1843/MAPO-7RLJ2A.

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The worldwide lithium consumption is chiefly associated with the industries such as primary aluminum, glass, ceramics and lubricants being distinguished however the increasing and strategical use of lithium in components of batteries, nuclear reactors, parts for the aeronautical industry and the manufacturing of pharmaceuticals. Production of lithium carbonate and lithium hydroxide, base of the chemical industry of lithium derivatives, is made exclusively by producers whose production comes from salt mines, exception to Brazil and China where lithium carbonate and lithium hydroxide are still produced from pegmatite minerals. The Brazilian production is practically restricted to the pegmatites of the north of Minas Gerais state and has the spodumene as the main mineral being mined. The production is also modest in relation to the world lithium industry. Flotation is not used in Brazil due mainly to the inherent difficulties associated to process selectivity during the separation of the spodumene from other silicates that occur in the pegmatites bodies. The flotation process is an alternative to add value to the current operation for the reason that the fines fraction, around minus 1 mm, originated from the gravitic beneficiation method being used, is currently discarded as tailings. The present work aimed at the investigation of the individual adsorption and coadsorption of anionic, cationic and amphoteric collectors as well as corn starch onto the surface of spodumene, microcline, muscovite and quartz. The investigation was performed with microflotation tests and zeta potential measurements. The results showed a concrete possibility of selective separation, through reverse flotation at pH 5.0, using primary amine acetate and direct flotation with sulfonates at pH 1.85. The adsorption mechanisms for both amines and sulfonates was controlled by forces of electrostatic type. With regard to muscovite, it is estimated that cation exchange capacity, due the K+ ion dissolution from its basal plane, was a collaborative mechanism for the cationic reagents adsorption. The main result from the collectors mixture was the amine and sulfonate coadsorption that maximized the floatability of microcline and muscovite. The tests performed with sodium oleate and corn starch have just confirmed the industrial practices of using these reagents for spodumene flotation. Two tests were carried out with a mixture of the four investigated minerals, and the results demonstrated again the possibility of selective separation of the spodumene.
A produção mundial de carbonato e hidróxido de lítio, base da indústria química de derivados de lítio, é feita exclusivamente por produtores cuja produção é obtida a partir de salinas, exceção feita ao Brasil que ainda produz carbonato e hidróxido de lítio a partir de minerais de pegmatitos. A produção brasileira está praticamente restrita aos pegmatitos do norte de Minas Gerais, tendo o espodumênio como principal mineral-minério, e é modesta em relação à produção mundial. A flotação não é empregada no Brasil devido, entre outros fatores, às dificuldades inerentes à seletividade da separação do espodumênio dos outros silicatos que ocorrem nos corpos pegmatíticos. O processo de flotação é uma alternativa para agregar valor ao processo uma vez que a fração fina, em geral menor que 1 mm, originada do beneficiamento, convencional é atualmente descartada como rejeito. Entre os principais minerais associados ao espodumênio, em pegmatitos brasileiros, estão a microclina, quartzo e a muscovita. O presente trabalho estudou a adsorção individual e coadsorção de coletores aniônicos, catiônicos, anfotéricos e amido de milho na superfície dos minerais espodumênio, microclina e quartzo, através de testes de microflotação e medidas de potencial zeta. Os resultados obtidos mostraram a possibilidade de separação seletiva do espodumênio, por flotação reversa, em pH 5,0, usando-se acetato de aminas primárias e flotação direta com o uso de sulfonatos em pH 1,85. Os mecanismos envolvidos na adsorção das aminas e sulfonatos nos minerais testados foram condicionados por forças de natureza essencialmente eletrostáticas. No caso da muscovita, estima-se que a capacidade de troca iônica deste mineral, através da dissolução de íons K+ do seu plano basal, foi um mecanismo colaborador para a adsorção dos reagentes catiônicos. O principal resultado da mistura de coletores foi a adsorção conjunta de amina e sulfonato que maximizou a flotabilidade da microclina e muscovita. Os testes com oleato de sódio e amido de milho simplesmente confirmaram a prática industrial corrente de uso destes reagentes.

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Klebow, Birthe [Verfasser]. "Monte Carlo studies of the aggregation of alkyltrimethylammonium surfactants on montmorillonite- and muscovite-water interfaces / Birthe Klebow." Hannover : Technische Informationsbibliothek und Universitätsbibliothek Hannover (TIB), 2012. http://d-nb.info/1024819868/34.

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27

Desage, Frédéric. "Précipitation des gaz rares dans le mica muscovite : endommagement sous irradiation : nature et croissance des cavités formées." Poitiers, 1995. http://www.theses.fr/1995POIT2335.

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Certains micas phlogopite qui contiennent de l'eau ont un coefficient de dilatation exceptionnel. Cette etude a pour objet d'incorporer par implantation ionique un gaz rare dans un mica anhydre en remplacement de l'eau, il s'agit de former des bulles de gaz rare entre les feuillets de mica afin de controler la dilatation. L'implantation de gaz rares s'accompagne toujours de l'amorphisation de la matrice meme lorsqu'elle est realisee a haute temperature. Les conditions de l'amorphisation ont ete obtenues lors d'une etude preliminaire d'irradiation par faisceau d'ions argon et helium. La fluence d'amorphisation depend essentiellement de l'energie deposee lors des chocs tres energetiques. L'observation par microscopie electronique en transmission d'echantillons implantes avec des ions helium a permis de mettre en evidence la presence de petites bulles dans un mica partiellement cristallin. Ce qui provoque la dilatation anormale. L'implantation des gaz rares plus lourds produit de nombreuses cavites dans un mica amorphe. Differentes analyses montrent que les gaz rares sont bien incorpores dans la matrice et que les cavites contiennent le gaz rare en phase fluide. La taille des cavites augmente avec la fluence tandis que leur densite diminue. Le gaz rare present dans les cavites peut etre solidifie a basse temperature et identifie par la mesure de son parametre cristallin. On en deduit la mesure du volume molaire a la temperature ambiante puis la pression dans les bulles en utilisant une equation d'etat pour le gaz rare fluide. Cette pression est tres voisine de la pression d'equilibre

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28

Gaber, Lawrence Jay. "On the significance of [superscript 40] Ar/[superscript 39] Ar incremental-heating of biotite, muscovite and amphibole /." The Ohio State University, 1991. http://rave.ohiolink.edu/etdc/view?acc_num=osu1487682558446173.

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29

Aouadj, Omar. "Etude du broyage humide de la muscovite : influence d'additifs de broyage acryliques : l'acide polyacrylique et ses oligomères." Mulhouse, 1994. http://www.theses.fr/1994MULH0338.

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Le broyage est une méthode courante d'obtention de charges industrielles pour les polymères, mais il consomme une quantité importante d'énergie et son processus complexe est encore mal connu. On sait qu'en ajoutant de très faibles quantités d'additifs, tels que des acides polyacryliques, on peut augmenter notablement son efficacité mais que ceux-ci ont aussi une grande influence sur les propriétés de surface des charges broyées. Le but de ce travail était de montrer comment ces additifs - l'acide polyacrylique (Mn=2550 mol/g) et ses oligomères (DP=2,3,4,5) ou le chlorure de potassium pouvaient influencer la cinétique de broyage, suivie par mesure de la surface spécifique et de la granulométrie des particules broyées ainsi que les propriétés de surface déterminées en recourant à la chromatographie inverse en phase gazeuse. Il a été clairement démontré que ces additifs de broyage influençaient très fortement la cinétique de broyage: le dimère et le chlorure de potassium IM se révélant les agents les plus efficaces par rapport à l'eau pure ou à une solution d'acide polyacrylique prises comme référence. La chromatographie inverse à dilution infinie montre aussi clairement que les propriétés de surface des muscovites broyées dans ces deux milieux différent notablement, la chromatographie inverse à concentration finie (obtention des isothermes d'adsorption et des fonctions de distribution des sites en énergie) démontre clairement que si la délamination des cristaux de muscovites se produit préférentiellement en présence de chlorure de potassium, par contre le dimère favorise nettement leur fracture

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30

Alva, Jimenez Tatiana Romy. "Variation in hydrothermal muscovite and chlorite composition in the Highland Valley porphyry Cu-Mo district, British Columbia, Canada." Thesis, University of British Columbia, 2011. http://hdl.handle.net/2429/38209.

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Muscovitic mica and chlorite are common alteration components in porphyry Cu-Mo deposits. Their mineral chemistry varies depending on the degree of fluid rock interaction, pressure and temperature and can therefore be used as alteration vector. At the Valley porphyry Cu-Mo deposit of the Highland Valley porphyry district, southern British Columbia, muscovitic mica forms part of the high-temperature K-silicate assemblage. It also forms in the adjacent Bethsaida Zone and the abandoned Alwin mine some 4 km to the west, where it is associated with quartz-sulfide veins. The host rock of these areas is granodiorite of the Bethsaida phase of the Guichon Creek batholith. In the Bethlehem deposits, fine- to medium-grained muscovitic mica and chlorite form parallel to fractures or disseminated in a more mafic host rock. The muscovitic mica forms as several textural varieties, including vein selvages where they replace the rock, replacement of igneous biotite and feldspar whereas chlorite replaces mostly biotite and amphibole. Muscovite in the core of the Valley deposit is sodium-bearing (ca. 0.6wt%Na2O, 0.8wt%MgO), but is more phengitic (ca. 0.2wt%Na2O, 1.29wt%MgO) at the Alwin mine and the Bethlehem deposits. Titanium, Li, Sn, V and Sr are present in higher concentrations in muscovites from the Valley deposit compared to those from other areas. In contrast Tl, Rb, Cs, B, Mn, Co and Zn concentrations are higher in muscovite from the Alwin mine, Bethsaida zone and Bethlehem than those from the Valley deposit. Major and trace element chemistry of muscovite reflects decreasing temperature and increasing pH from the central porphyry zones Valley to the peripheral hydrothermal systems. High concentrations of Cs, Rb and Tl in whole-rocks indicate extensive muscovite alteration, whereas high Li, Zn, Mn and Co relate to abundant hydrothermal chlorite in the whole rock. The variability in the chemistry of muscovite and chlorite is also detected using short-wave infrared spectra (SWIR). An absorption feature between 2200 nm to 2202 nm characterizes the Na-bearing muscovites from Valley, whereas more phengitic-muscovites from Alwin and Bethlehem deposits have an absorption feature between 2205 nm to 2209 nm. Mg-rich chlorites have an absorption feature at around 2341 nm, whereas the same feature shifts to 2350 nm for Fe-rich chlorites. Muscovite and chlorite chemistry varies laterally in porphyry Cu-Mo districts and is also reflected in SWIR spectra and whole rock geochemistry, techniques widely used in exploration.

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31

Onike, F. N. "Time-temperature-transformation (TTT) curves for and the thermal decompsition reactions of kaolinite, montmorillonite and two muscovite samples." Thesis, University of Hull, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.377390.

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32

Relosi, Natanael. "Obtenção e caracterização de tintas em pó base epóxi/poliéster com incorporação de argilominerais : montmorilonita (MMT) e mica muscovita." reponame:Repositório Institucional da UCS, 2016. https://repositorio.ucs.br/handle/11338/1176.

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Um dos sistemas de proteção de substratos metálicos mais comumente empregado na indústria é o de tintas. Os fatores favoráveis à utilização das tintas em pó incluem a não utilização de solventes, facilidades de processamento/aplicação e possibilidade de reaproveitamento do material que não aderiu na superfície da peça. As características térmicas, mecânicas e químicas da tinta são influenciadas principalmente pelo tipo de resina utilizada. As tintas em pó híbridas (epóxi/poliéster) visam conciliar a característica de resistência ao intemperismo e ação dos raios UV com as características de resistência química e mecânica. Nas tintas em pó podem ser adicionados nanocargas que tem por finalidade melhorar as propriedades térmicas, mecânicas e químicas dos revestimentos. Outra característica das nanocargas é o baixo custo financeiro, decorrente da utilização de uma menor quantidade de carga, com elevado nível de desempenho. Dentre as nanocargas utilizadas, pode-se citar a mica muscovita e a montmorilonita 30B (MMT 30B) que, quando incorporadas às tintas, mesmo em baixas concentrações, apresentam propriedades de barreira superiores que às cargas convencionais. Este trabalho tem por objetivo desenvolver e caracterizar uma tinta em pó híbrida contendo diferentes teores de mica muscovita e MMT 30B. Os argilominerais foram incorporados numa formulação padrão de tinta em pó híbrida nas proporções de 2, 4 e 6% (m/m), separadamente. Antes da aplicação da tinta, os substratos metálicos foram submetidos a um pré-tratamento de fosfatização com fosfato de zinco. Após isso, a tinta em pó foi aplicada em painéis com dimensões de 70 x 120 x 0,65 mm de aço carbono AISI 1010 através de pulverização eletrostática. Os argilominerais, a tinta em pó e o revestimento foram analisados empregando diferentes técnicas de caracterização, tais como análise granulométrica, análise termogravimétrica (TGA), calorimetria exploratória diferencial (DSC), espectroscopia de infravermelho por transformada de Fourier (FTIR) e microscopia eletrônica de varredura por emissão de campo (MEVFEG). O efeito da incorporação dos argilominerais nas propriedades físicas e de proteção à corrosão das tintas foi avaliado com ensaios de medida de brilho, aderência, flexibilidade, resistência ao impacto, impedância eletroquímica (EIE), exposição à névoa salina (NS) e ensaio de chama. Para todas as tintas contendo argilominerais foi constatado o aumento da dureza superficial e a redução de brilho com o aumento do teor do argilomineral, sendo este efeito mais pronunciado com a adição de 6% (m/m) de MMT 30B. A aderência da tinta ao substrato não foi alterada pela presença dos argilominerais. As tintas contendo mica muscovita apresentaram melhores resultados nos ensaios de resistência ao impacto e de flexibilidade quando comparados as tintas contendo MMT 30B, nas concentrações testadas. A amostra TH/6/MICA apresentou melhor resultado no ensaio de impedância eletroquímica em relação aos outros sistemas estudados. No ensaio de névoa salina todas as amostras apresentaram elevada proteção à corrosão. Não foram observados bolhas ou pontos de corrosão na superfície de nenhuma das amostras. Porém, no ensaio subsequente de migração subcutânea, a amostra TH/2/MMT 30B foi a que apresentou maior desplacamento. No ensaio de chama, as tintas com incorporação de mica muscovita apresentaram melhores resultados que as tintas com MMT 30B. Após a análise de todos os ensaios, conclui-se que a adição de mica muscovita na proporção de 4% resultou em uma tinta com melhores propriedades térmicas, mecânicas e químicas.
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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior.
One of metallic substrates protection systems most commonly used in the industry is the paint. Factors favorable to the use of powder coatings include non-use of solvents, processing facilities/application and the possibility of reuse of material that did not adhere to the surface of the pieces. The thermal, mechanical and chemical characteristics of the obtained paint are influenced principally by the type of resin used. Hybrid (epoxy/polyester) powder coatings aimed at reconciling the weathering resistance characteristic and action of UV rays with the chemical resistance and mechanical characteristics. In the powder coatings can be added nanofillers which aims to improve the thermal, mechanical and chemical coatings. Another feature of nanofillers is the low financial cost resulting from the use of a lesser amount of filler, with a high level of performance. Among the nanofiller used, it can be cited muscovite mica and montmorillonite 30B (MMT 30B) that, when incorporated into the coatings, even at low concentrations, have higher barrier properties than conventional fillers. This work aims to develop and characterize a hybrid powder coating containing different amounts of muscovite mica and MMT 30B. Clayminerals have been incorporated in a standard formulation hybrid powder coatings in proportions of 2, 4 and 6% (w/w). Before applying the coating, the metal substrates were subjected to a pretreatment phosphating with zinc phosphate. After this, the powder paint was applied to panels with dimensions 70 x 120 x 0.65 mm carbon steel AISI 1010 through electrostatic spraying. The clayminerals, the powder paint and coating were analyzed using various characterization techniques, such as particle size analysis, thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), infrared spectroscopy in Fourier transform (FTIR) and scanning electron microscopy for field emission (SEM-FEG). The effect of the incorporation of clayminerals in the physical properties and corrosion protection of coatings was evaluated with brightness measurement tests, adhesion, flexibility, impact resistance, electrochemical impedance spectroscopy (EIS), exposure to fog saline (NS) and flame test. For all coatings containing clayminerals was found to increase the surface hardness of the coating and reduced gloss with increasing clay content, this being more pronounced effect with the addition of 6% (w/w) of MMT 30B. The adhesion of the coating to the substrate was not altered by the presence of clayminerals. The coatings containing mica muscovite showed better results in impact resistance tests and flexibility when compared to coatings containing MMT 30B. The sample TH/6/MICA showed better results in the electrochemical impedance test in relation to other systems studied. In the salt spray test all samples showed high corrosion protection. There were no blistering or corrosion spots on the surface of any of the samples. However, in the subsequent test of subcutaneous migration, the sample TH/2/MMT 30B showed the greatest peeling. In the flame test, coatings with incorporation of muscovite mica showed better results than coatings with MMT 30B. After analyzing all the tests, it is concluded that the addition of muscovite mica in the proportion of 4% resulted in an paint with improved thermal, mechanical and chemical properties.

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33

Marchal, Karen L. "Geochemistry, Mineralogy and Evolution of Mica and Feldspar from within the Mount Mica Pegmatite, Maine, USA." ScholarWorks@UNO, 2014. http://scholarworks.uno.edu/td/1822.

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Mount Mica is a poorly zoned sodic LCT-type pegmatite consisting dominantly of quartz, albite and muscovite in the outer portions. Potassium feldspar and lepidolite are restricted to the core zone. Micas in the wall zone are chemically homogeneous, but abruptly evolve into higher Cs + Rb bearing lithian muscovites and lepidolites in the core zone. The abrupt increase of the Cs, Rb in K-feldspar, and Cs, Rb and F in muscovite, and lepidolite combined with the occurrence of highly evolved species lepidolite, pollucite, elbaite, beryl and spodumene in the core zone suggests that incompatible elements were retained in residual fluid until their concentration was high enough to initiate crystallization of incompatible-rich mineral phases. The relatively low abundance of incompatible elements in the hanging wall suggest that the fractionation process was efficient in sweeping incompatibles into the core-zone, producing proportionally small volumes inside the pegmatite with very high enrichment in incompatible elements.

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34

Britz, Susan Marina Verfasser], and Wolfgang [Akademischer Betreuer] [Durner. "Europium sorption experiments with muscovite, orthoclase, and quartz: Modeling of surface complexation and reactive transport / Susan Marina Britz ; Betreuer: Wolfgang Durner." Braunschweig : Technische Universität Braunschweig, 2018. http://d-nb.info/1175890332/34.

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35

Wood, Patricia Ann. "Petrogenesis of the Spruce Pine pegmatites, North Carolina." Thesis, This resource online, 1996. http://scholar.lib.vt.edu/theses/available/etd-08222008-063320/.

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36

McMullin, David William Augustine. "Thermobarometry of pelitic rocks using equilibria between quartz-garnet-aluminosilicate-muscovite-biotite, with application to rocks of the Quesnel Lake area, British Columbia." Thesis, University of British Columbia, 1990. http://hdl.handle.net/2429/31043.

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Rocks of the Quesnel Lake area are divided into three units: unit 1, a continental margin sequence; unit 2, The Crooked Amphibolite (an ocean-floor sequence); and unit 3, the Quesnel sedimentary and volcanic sequence. Two conglomerate localities within unit 3 contain clasts identified as being derived from deformed rocks of units 1 and 2. Deformation of the combined package of units 1 and 2 must have accompanied the emplacement of unit 2 onto unit 1 sometime between the deposition of unit 2 (Mississippian - Permian) and the deposition of unit 3 (Triassic - Jurassic). Rocks of unit 1 have been divided by earlier workers into the Barkerville and Cariboo terranes, separated by the Pleasant Valley Thrust. An extensive review shows that the two terranes are stratigraphically similar and share most of their structural history. The Pleasant Valley Thrust, if it exists, is an extremely early structure. These data do not satisfy the criteria for naming these units 'terranes'. The rocks of unit 1 and 2 experienced an extra phase of deformation not seen in rocks of unit 3. A total of five phases of folding are present. Phases 1 through 4 are approximately coaxial with northwest axes and variably oriented axial planes. Phase 5 has northeast trending axes and vertical axial planes. F₁ is seen in units 1 and 2 only and is visible in outcrop as rootless isoclinal folds and a transposed foliation. In thin section, S₁ is only preserved within the earliest garnet porphyroblasts. F₂ folding is the major deformational event. Peak metamorphism accompanied and outlasted it. Major F₂ folds are present in the field and are accompanied by an axial planar foliation. In thin section, S₂ wraps around earlier porphyroblasts but is overgrown by later ones (staurolite, kyanite). F₃ folding is responsible for the major map-scale structures. It postdated the peak of metamorphism and isograds axe folded by it. In thin section S₃ is commonly a crenulation cleavage or transposed foliation. Some late mineral growth accompanied the early stages of F₃. F₄ and F₅ are buckle folds and kinks and may be conjugate fold sets from a single deformational event. They are not generally visible in thin section. The assemblage silica - garnet - aluminosilicate - mica (SGAM) is common in amphibolite grade meta-pelitic rocks, and can be used as a thermobarometer if the activities of muscovite and biotite can be calculated accurately. A new method of calculating the ideal activity of mica components is proposed. Standard models do not adequately account for the degree of coupled substitution that takes place. The proposed method stores the site occupancies in a 4-dimensional array and manipulates the entries to satisfy three criteria. 1: That non-permitted ionic configurations (species) have an activity of zero. 2: That the sum of all activities is unity. 3: That the sum of all activities of species containing a particular ion in a particular site is the site occupancy of that ion. The method is computationally simple and yields activity values that satisfy the distribution of species equations of an ideal complex solution model. Standard state properties for annite and Margules solution parameters for biotite are determined using mathematical programming techniques on published experimental and natural assemblage data. Published volume data indicate that Fe-Mg mixing in biotite is ideal. The data permit the calculation of four Margules parameters (MgTi, FeTi, MgAl, FeAl). The differences MgTi - FeTi and MgAl - FeAl are similar to those found by previous workers but the treatment of the data suggests moderately large individual values for the Margules parameters (up to 75 kJ/mol). Using these activity models the SGAM thermobarometer is applied to several sets of published analyses which show that this calibration offers distinct improvements over previous calibrations. Pressures determined using the new calibration are consistent with other barometers and the aluminosilicate polymorph present. In addition, several data sets show field gradients, particularly in P, not previously recognized and which agree with field observations. The SGAM barometer applied to the analytical data from the Quesnel Lake area yields pressures and temperatures that are consistent with the mapped isograds. The pressure and temperature gradients indicate that the final setting of the thermobarome-ter was diachronous across the area and during the early stages of F₃ folding. Hot rocks in cores of anticlines 'set' at later times and at shallower depths than cooler rocks in adjacent synclines. Tight spacing of isograds is more consistent with post-metamorphic folding than with high thermal gradients.
Science, Faculty of
Earth, Ocean and Atmospheric Sciences, Department of
Graduate

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Vatti, Anoop Kishore [Verfasser], Ralf [Gutachter] Drautz, and Jörg [Gutachter] Neugebauer. "An ab initio study of muscovite mica and formation energy of ions in liquid water / Anoop Kishore Vatti ; Gutachter: Ralf Drautz, Jörg Neugebauer." Bochum : Ruhr-Universität Bochum, 2017. http://d-nb.info/1125106298/34.

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38

Ozun, Savas. "Flotation Characteristics Of Minerals In Feldspar Ores." Phd thesis, METU, 2012. http://etd.lib.metu.edu.tr/upload/12614273/index.pdf.

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Albite (Na-feldspar) and orthoclase (K-feldspar) are the major feldspar minerals used in the production of glass and ceramics. They are found together with impurities like biotite, muscovite, quartz and rutile which are not desired for ceramics and glass industries. Therefore, these have to be removed to make the ore available for industrial use. In order to shed light on the actual feldspar ores, in this study
the flotation characteristics of albite, biotite, muscovite, orthoclase, quartz and rutile were investigated separately in their pure forms. In the investigation, the electrokinetic potential measurements and micro-flotation studies have been carried out to get information about their flotation characteristics under the effect of three different collectors, Aero 704, Aero 3000C and Aero 825, and the pH of the medium. The flotation recoveries were found to be pH dependent and the effective between the pH range of 7.0 and 11.5 in the presence of Aero 704. In the case of flotation with Aero 3000C, the recoveries reached up to 95.0% at certain concentrations and pH values and decreased sharply below pH 3.0 and above pH 9.5 for all the minerals tested. In the presence of Aero 825, the flotation recoveries of the minerals except for rutile, were found to be insufficient even with its highest concentration. In order to evaluate the adsorption mechanism of the collectors, Atomic Force Microscopy (AFM) and Fourier Transform Infrared Spectroscopy (FTIR) analyses were carried out. From the AFM results it might be deduced that the behavior of Aero 3000C and Aero 825 was found to be almost similar for biotite and muscovite as monolayer adsorption and for the remaining minerals, albite, orthoclase, quartz and rutile, as monolayer and bilayer adsorption together. In the case of Aero 704, for albite and orthoclase, the adsorption of the collector might be the reason for monolayer and bilayer formation on their surfaces. The strength of the interaction of the collectors on the mineral surfaces was followed by FTIR analyses before and after acetone washing. The interaction of all the collectors was found to be weak in the case of albite, orthoclase, quartz and rutile whereas the interaction of Aero 704 and Aero 3000C was found to be strong in the case of biotite and muscovite.

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39

Abd, Elmola Ahmed. "Deformation conditions and 40Ar/39Ar dating of fault activity registered by phyllosilicates (clay minerals) in a sedimentary environment : examples of the south-verging thrust faults in the Pyrenees." Thesis, Bourgogne Franche-Comté, 2017. http://www.theses.fr/2017UBFCD033/document.

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La chaîne pyrénéenne présente des structures de déformation bien exposées et des roches sédimentaires syntectoniquesbien conservées qui en font un objet idéal pour étudier les failles. En effet, les textures, structures, compositions chimiques etisotopiques enregistrées par le coeur de la faille chevauchante peuvent renseigner sur les conditions et mécanismes de ladéformation et aussi contraindre dans le temps l’activité de la faille étudiée. Dans la présente thèse, trois chevauchements duversant sud Pyrénéen ont été étudiés pour mieux appréhender le comportement mécanique, chimique et isotopique desphyllosilicates dans des roches sédimentaires déformées. Ces roches sont d'âge éocène à triasique et sont impliquées dans degrand chevauchements (zone cisaillantes) à vergence sud. Ce travail combine observation pétrographique, analyse chimique,modélisation thermodynamique et technique de datation radiométrique 40Ar/39Ar sur des minéraux de moscovite/illite et dechlorite. La première faille étudiée est le chevauchement du Pic de Port Vieux (PPV), chevauchement de second ordre lié auchevauchement majeur de Gavarnie dans le sud-ouest de la Zone Axiale Pyrénéenne. Des mécanismes de pression-dissolutionet recristallisation, accompagnés d’interactions avec un fluide très réducteur sont les principaux paramètres responsables deschangements minéralogiques/chimiques observés dans la zone centrale de la faille. L'indice Kübler de la moscovite et lesdonnées thermométrique sur chlorite suggèrent des températures de 285°C ± 28°C pour l'activité de PPV. De plus, la datation40Ar/39Ar de la moscovite syn-cinématique indique que la faille a fonctionné il y a 36.9 ± 0.2 Ma, ce qui coïncide avec l’âge del'activité du chevauchement de Gavarnie. Les deux autres failles étudiées sont le chevauchement de Lakora qui est situé sur lebord sud de la zone Nord Pyrénéenne et celui de Monte Perdido (au niveau de Torla) situé dans la partie ouest de la zone Sud-Pyrénéenne. Ces deux chevauchements ont été affectés (déformés) par la mise en place de chevauchement de Gavarnie. Lesobservations pétrographiques et les analyses microstructurales ont démontré que la déformation est marquée par du plissement,du boudinage, par le développement d'une schistosité intense, de surfaces de cisaillement, de veines et par un enrichissement enphyllosilicates au coeur de la zone de faille des deux chevauchements. De manière similaire au chevauchement du Pic de PPV,les mécanismes de pression-dissolution et recristallisation sont les principaux mécanismes qui contrôlent la déformation et ilssont à l’origine de l'enrichissement en phyllosilicates néoformés dans les zones de failles des deux chevauchements. En se basantsur les mesures de l'indice de Kübler, il apparait que la déformation de Lakora et Torla s'est produite dans des conditions detempérature plus basse que celles enregistrées pour le chevauchement du PPV. Par ailleurs, es âges les plus jeunes obtenus parla technique 40Ar/39Ar ne peuvent être rattachés à l'âge de la déformation car ils sont plus vieux que les âges des sédimentsimpliqués dans les zones de faille. D'autres hypothèses sont proposées à la fin de cette thèse afin de comprendre les raisons decette incohérence dans les âges et afin de dater la déformation de Lakora et Torla. Ainsi l'ensemble des résultats de cette thèsemontrent que les minéraux phyllosilicatés peuvent être des outils thermochronologiques fiables permettant de dater avecprécision l'activité des failles lorsqu'ils ont été combinés avec des préparations d'échantillons précises et caractérisation détailléedes échantillons
The Pyrenees belt features well-exposed deformation structures and well preserved syntectonic sedimentary rocksthat make it ideally suited to study thrust faults. The texture, structure and chemical-isotopic compositions of synkinematicphyllosilicates are widely used to estimate the deformation conditions-mechanisms and timing of fault activities. Therefore, inthe present thesis, three thrusts from the Pyrenean orogen have been studied to better understand the mechanical, chemical andisotopic behavior of phyllosilicates from deformed sediments of Eocene-Triassic age that have been involved in large southvergingshear zones. This work combined petrographic observation, chemical analyses, and thermodynamic modeling with40Ar/39Ar geochronology on muscovite/illite and chlorite. The first studied fault is the Pic de Port Vieux thrust (PPVT), a secondorderthrust related to the major Gavarnie thrust (GT) in the south-western part of the Pyrenees Axial Zone. The dissolutionrecrystallization,pressure solution mechanisms, and interaction with highly reductive fluids are the main parameters responsiblefor the mineralogical and chemical changes in the fault core zone. The Kübler index and chlorite thermometry suggest upperanchizoneto epizone conditions with a temperature of 285°C ± 28°C for the PPVT activity. Moreover, the 40Ar/39Ar step-heatingdating of synkinematic muscovite indicates that the fault activity occurred at 36.9 ± 0.2 Ma which coincides with the activity ofthe GT. The two other faults are: Lakora thrust that is located on the southern edge of the North Pyrenean Zone, and the MontePerdido thrust (Torla location) situated on the western part of the South Pyrenean Zone. The two thrust are affected (deformed)by the emplacement of the Gavarnie thrust. The petrographic-microstructural analyses on these faults demonstrated thatdeformation is marked by folding, boudinage, intense cleavage, shear surfaces/veins and enrichment of phyllosilicates in thefault zone of both thrusts. Similar to the PPVT, pressure-solution and dissolution-recrystallization mechanisms are the mainmechanisms that control deformation and enhanced the enrichment of the newly-formed phyllosilicates in the fault zones ofboth thrusts. Based on the Kübler index measurements, the deformation in the Lakora and Torla faults occurred at relativelylower temperature compared to the PPVT. The youngest total gas ages obtained by the 40Ar/39Ar technique are very old for theactivity time of both thrusts as they are older than the depositional ages of the sediments in the fault zones. Further investigationsare proposed at the end of this dissertation in order to better understand this anomaly in age and to successfully obtain the rightage of the two thrusts activity.Based on the results of this thesis, phyllosilicate minerals proved to be reliable thermochronological tools for fault activity atlow-grade metamorphism, when such tools are combined with careful sample preparations and detailed sample characterization

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Vaculík, Josef. "Využití slídového separátu z plavení kaolinu." Master's thesis, Vysoké učení technické v Brně. Fakulta chemická, 2020. http://www.nusl.cz/ntk/nusl-414138.

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The Master’s Thesis aims to laboratory test the possibilities of utilization mica separate, which arises during the process of floating kaolin as a by-product together with sand. Mica and sand are then separated by flotation or vibration. The mica separate thus formed was subjected to analysis. XRD and heating microscopy methods were used for analysis. Subsequently, experiments with mica separation as a filler in composites based on epoxy resins were set up and performed. Furthermore, the separate was tested as a part of plasters and visual building elements. Last but not least, the separate was mixed into the ceramic, which was then subjected to firing in the selected mode. The diploma thesis provides a comprehensive overview of the above-mentioned possibilities of using mica separation, which is based on a sufficient amount of experimental data.

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Delavernhe, Laure. "Etude multi-échelle de la réactivité des altérites lors du traitement à la chaux." Nantes, 2011. http://www.theses.fr/2011NANT2083.

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De nos jours le développement durable et les mesures de protection pour l’environnement se développent avec des conséquences importantes pour la gestion des ressources naturelles. Les aménagements du territoire, et particulièrement les travaux de terrassements, sont directement concernés par ces nouvelles directives avec un objectif de « zéro apport-zéro déchet » de matériaux. Cependant les sols naturels, et notamment les sols argileux, ne satisfont pas les critères géotechniques. Plusieurs chantiers de terrassements dans le Nord-Ouest de la France rencontrent des difficultés avec des sols fins résultants de l’altération de sédiments du massif Armoricain ne satisfaisant pas les exigences mécaniques et de stabilité, même traités classiquement avec de la chaux et / ou des liants hydrauliques. L’approche multi-échelle mise en oeuvre dans ce travail nous a mené à caractériser la forte sensibilité à l’eau de ces matériaux, propriété critique pour la réalisation de déblais notamment. Un effet composite entre les minéraux de kaolinite et de muscovite à l’origine de cette sensibilité à l’eau a été mis en évidence par l’étude des interactions en suspension de ces deux minéraux. Les gains de cohésion des matériaux développés lors de leur traitement à la chaux permettent d’envisager leur valorisation sur chantier en respectant quelques précautions. La discussion de la nature des différentes forces de cohésion dans les matériaux naturels et traités permet de proposer plusieurs hypothèses pour expliquer l’évolution particulière des performances mécaniques de ces matériaux par rapport aux sols développant classiquement de bonnes performances
Nowadays interest of environment protection and sustainable development is growing up, leading to improve natural resources management. Land settlement, and more precisely earthworks, is directly concerned with this new policy in order to limit using of external materials with an objective of « no adding - no waste ». Nevertheless, some crude soils as soft clays or clayed silt do not satisfy geotechnics criteria for a safe use. Several earthworks on North West of France have met difficulties with fine grained soils from high weathering sediment from Armorica massif. These soils do not check mechanical and swelling requirements even if they are treated with different common mixtures of lime and/or hydraulic binders. The multi-scale characterisation performed during this study allows us to understand the high water sensibility of these materials which is their main critical property. A composite effect between kaolinite and muscovite minerals responsible for their water sensibility is evidenced at macroscopic scale. It has been confirmed by clay minerals interactions in colloidal suspension. Improvements of soil cohesion obtained by lime treatment allow us to envisage their use on earthwork site if some cautions are taken. Discussions about different strength cohesion nature for crude and treated soils underline several hypotheses for explaining peculiar mechanical properties development compared with classical sustainable materials

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Delavernhe, Laure. "Étude multi-échelle de la réactivité des altérites lors du traitement à la chaux." Phd thesis, Université de Nantes, 2011. http://tel.archives-ouvertes.fr/tel-00671340.

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De nos jours le développement durable et les mesures de protection pour l'environnement se développent avec des conséquences importantes pour la gestion des ressources naturelles. Les aménagements du territoire, et particulièrement les travaux de terrassements, sont directement concernés par ces nouvelles directives avec un objectif de " zéro apport-zéro déchet " de matériaux. Cependant les sols naturels, et notamment les sols argileux, ne satisfont pas les critères géotechniques. Plusieurs chantiers de terrassements dans le Nord-Ouest de la France rencontrent des difficultés avec des sols fins résultants de l'altération de sédiments du massif Armoricain ne satisfaisant pas les exigences mécaniques et de stabilité, même traités classiquement avec de la chaux et / ou des liants hydrauliques. L'approche multi-échelle mise en œuvre dans ce travail nous a mené à caractériser la forte sensibilité à l'eau de ces matériaux, propriété critique pour la réalisation de déblais notamment. Un effet composite entre les minéraux de kaolinite et de muscovite à l'origine de cette sensibilité à l'eau a été mis en évidence par l'étude des interactions en suspension de ces deux minéraux. Les gains de cohésion des matériaux développés lors de leur traitement à la chaux permettent d'envisager leur valorisation sur chantier en respectant quelques précautions. La discussion de la nature des différentes forces de cohésion dans les matériaux naturels et traités permet de proposer plusieurs hypothèses pour expliquer l'évolution particulière des performances mécaniques de ces matériaux par rapport aux sols développant classiquement de bonnes performances.

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Мозговий, Іван Павлович, Иван Павлович Мозговый, and Ivan Pavlovych Mozghovyi. "Схід-захід: дилема чи проблема українського вектору?" Thesis, Сумський державний університет, 2005. http://essuir.sumdu.edu.ua/handle/123456789/21702.

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В суспільно-політичній думці України впродовж останніх майже чо-тирьох століть набуває тієї чи іншої гостроти питання подальших орієнтацій та пріоритетів українського розвитку. При цьому наголошується на дилемі найбільш вірогідної орієнтації на Схід чи Захід. Майже до кінці XX ст. промосковські ідеологи нав’язували нашій громадськості тезу про “історичну” обумовленість потягу України в напрямку східного (євразійського) простору. Сьогодні такі твердження не витримують елементарної критики.

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Rêve, Jean-Michel. "Répartition de l'uranium et du thorium dans les roches alcalines des Vosges du Nord : granite du Kagenfels." Paris 11, 1985. http://www.theses.fr/1985PA112015.

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Le massif du Kagenfels est un filon annulaire constitué de la base d’une coupole granitique et de son filon d’alimentation rhyolitique. Le granite est métalumineux à biotite. L’ensemble des caractéristiques structurales et chimiques vont en faveur d’une appartenance au magmatisme anorogénique alcalin. Les micas, riches en lithium, montrent une évolution depuis des biotites jusqu’à des muscovites ferrifères. Ils constituent une série complète qui n’a encore jamais été observée dans le magmatisme anorogénique. Cette évolution est due aux conditions oxydantes et à l’abondance des phases fluides résiduelles comme en témoigne également la présence de miaroles. Le massif n’est constitué que d’un seul type chimique. Les rares variations chimiques observables : diminution des teneurs en uranium, corrélation négative entre potassium et sodium sont dues à des circulations hydrothermales qui affectent une région localisée du filon d’alimentation. L’uranium et le thorium sont répartis dans 5 minéraux : - thorite et zircon précoces, - monazite et zirconosilicate tardifs, - silico-phosphate de thorium secondaire. La répartition de ces éléments est gouvernée par 6 processus principaux : - la différenciation magmatique : ensemble des phénomènes antérieurs à la formation du magma et dont résultent les teneurs en uranium (6-10 ppm) et thorium (35-45ppm). – une différenciation magmatique lors de la cristallisation qui induit des teneurs en Th moins élevées des faciès de bordure situés au nord du massif. – une différenciation minéralogique due à la cristallisation rapide des granophyres qui empêche l’apparition de la thorite et du zircon. – une concentration de U et Th dans les fluides résiduels. – en fin de cristallisation, une incorporation préférentielle dans la monazite et les zirconosilicates plutôt que dans le zircon tardif. – un lessivage hydrothermal de l’uranium par des fluides enrichis en sodium
The Kagenfels’s massif is a ring-dyke constituted by the basement of a granitic cupola and her rhyolitic mother-lode. The granite is metaluminous biotite granite. Both chemical and structural characters are symptomatic of anorogenic alkaline magmatism. The micas, which are Li-rich, show an evolution from biotites to ferriferous muscovites. They represent a complete suite which has never been observed in this kind of magmatism. This evolution takes place under oxidizing conditions with the presence of abundant residual fluids as also indicated by many marioles. The chemistry is practically unvariant. The only small variations: decrease of uranium contents and negative correlation between sodium and potassium result from hydrothermal circulations which are located in a small region of the mother lode. Uranium and thorium are included in 5 minerals: - early thorite and zircon. – latter monazite and zirconosilicate. – Secondary thorium silico-phosphate. The distribution of U and Th is controlled by 6 principal processus: - magmatic differenciation: sum of all the phenomenons preceedind the Kagenfels’s magma formation from which result uranium contents (6-10 ppm) and thorium contents (35-45 ppm). – a magmatic differenciation during the crystallization: lower Th contents of the north border-zone. – mineralogic differenciation due to the fast crystallization of granophyres which prevent the formation f thorite and zircon. – U and Th concentration in the residual fluids. – in the late stage of crystallization, incorporation of U and Th rather in monazite and zirconosilicate than in latter zircon. – uranium hydrothermal leaching bu Na-enriched fluids

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DEVINEAU, Karine. "DESTABILISATION HAUTE TEMPERATURE DE POUDRES GRANITIQUES : EVOLUTION DES PROPRIETES MINERALOGIQUES ET PHYSIQUES." Phd thesis, Institut National Polytechnique de Lorraine - INPL, 2002. http://tel.archives-ouvertes.fr/tel-00010105.

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L'objectif de ce travail est double : 1- Etudier les déstabilisations thermiques de poudres de granites altérés, 2- Valoriser leur utilisation dans la formulation de céramiques traditionnelles, les assemblages minéralogiques des granites altérés (argiles, quartz, feldspaths) étant les principales matières premières entrant dans la formulation de ces produits. A- Analyse statistique des relations entre propriétés élémentaires de granites altérés et propriétés d'usage des céramiques traditionnelles Pour mener à bien cette étude, une trentaine de poudres de granites plus ou moins altérés sont compactées, séchées puis cuites à 1050 et 1175°C pendant 3h30, conditions se rapprochant de celles utilisées dans l'industrie céramique. De nombreux paramètres chimiques et physiques sont mesurés sur poudres et à chaque étape de l'élaboration du produit céramique. Les données obtenues sont traitées à l'aide de l'analyse statistique en composantes principales normées (ACP) afin de déterminer les paramètres clés qui interviennent dans les différentes étapes d'élaboration du produit céramique et qui contrôlent ses propriétés d'emploi. Cette étude statistique a démontré que : 1- la teneur en fer, la quantité de feldspaths et de micas sont les trois paramètres qui influencent la couleur et/ou les propriétés mécaniques des tessons ; 2- les conditions de mise en œuvre des éprouvettes avant cuisson influencent la porosité avant et après cuisson ; 3- les argiles favorisent la cohésion des éprouvettes avant cuisson. De cette étude, il ressort qu'il serait possible de formuler des céramiques à partir de granites altérés. B- Déstabilisation thermique des minéraux granitiques. Applications au système quartz-feldspaths et à la muscovite La deuxième partie détaille les transformations texturales des poudres granitiques en liaison avec les déstabilisations minéralogiques induites par le traitement thermique. Des éprouvettes de poudre compactée sont chauffées à 1175°C pendant 5, 10, 40 minutes et 3, 24, 68 heures à pression atmosphérique puis trempées dans l'air. Les cinétiques de transformations sont analysées par des méthodes microscopiques, la microsonde électronique, la diffraction des rayons X, l'analyse d'images et la spectroscopie infra-rouge. A l'exception du quartz, les minéraux sont déstabilisés en moins de 3 heures. La fusion du matériel feldspathique entraîne une forte réduction de la porosité aussi bien à l'intérieur qu'entre les agrégats de particules. Une porosité occluse subsiste cependant au sein de la phase liquide continue : elle se présente sous la forme de pores sphériques et elle est engendrée par le piégeage de vapeur d'eau. La disparition de la muscovite est effective dès 5 minutes de chauffage et les produits néoformés sont des baguettes silico-alumineuses de type spinelle puis mullite associées à une phase liquide qui apparaît progressivement avec le mûrissement textural des minéraux. L'orientation des baguettes est gouvernée par la cristallographie de la muscovite mère. Contrairement à la matrice quartzo-feldspathique, la déstabilisation de la muscovite provoque l'apparition d'une porosité occluse par la formation de pores piégeant une faible quantité d'eau issue de la déshydoxylation du phyllosilicate. L'augmentation de cette porosité avec la durée du chauffage est provoquée par l'arrondissement des pores dont la morphologie est initialement contrôlée par la cristallographie de la muscovite mère. Cette évolution texturale est rendue possible par le mûrissement textural des baguettes néoformées qui induit une diminution de la rigidité du système et un relâchement des contraintes. Cependant, compte tenu de la faible teneur en muscovite dans les matériaux granitiques étudiés, la porosité issue de sa déstabilisation reste négligeable par rapport à la porosité totale des tessons.

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Castro, Raimundo Jos? de Sousa. "Efeito da adi??o de feldspato e/ou res?duo de caulin em formula??es ? base de argila il?tica." Universidade Federal do Rio Grande do Norte, 2010. http://repositorio.ufrn.br:8080/jspui/handle/123456789/12778.

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Made available in DSpace on 2014-12-17T14:07:06Z (GMT). No. of bitstreams: 1 RaimundoJSC_TESE.pdf: 1754370 bytes, checksum: 88d2811dd20d4c281cc4bc5a58cfc6fa (MD5) Previous issue date: 2010-11-16
The red pottery industry in Piau? state is well developed and stands out at the national context for the technical quality of its products. The floor and wall tile industry, however, is little developed since the state has only one company that produces red clay-based ceramic tiles. This thesis aims at using the predominantly illitic basic mass of the above mentioned industry, with the addition of feldspar and/or kaolin residue in order to obtain products of higher technical quality. Kaolin residue consists basically of kaolinite, muscovite mica and quartz; the feldspar used was potassic. In this experiment, basic mass (MB) was used for experimental control and fifteen formulations codified as follows: F2, F4, F8, F16, F32, FR2, FR4, FR8, FR16, FR32, R2, R4, R8, R16 and R32. All raw materials were dry-milled, classified, formulated and then humidified to 10% water. Thereafter, test samples were produced by unixial pressing process in a rectangular steel matrix (60.0 x 20.0 x 5.0) mm3 at (25 MPa). They were fired at four temperatures: 1080?C, 1120?C, 1160?C, with a heating rate of 10?C/min during up to 10 min in an electric oven, and the last one in an industrial oven with a peak of 1140?C, aim ing to confirm the results found in laboratory and, finally, technological tests were performed: MEA, RL, AA, PA, TRF and PF. The results revealed that the residue under study can be considered a raw material with large potential in the industry of red clay-based ceramic tiles, since the results found both in laboratory and in the industry have shown that the test samples produced from the formulations with up to 4% feldspar and those produced with up to 8% feldspar and residue permitted a reduction in the water absorption rate and an increase in the mechanical resistance while those samples produced with up to 4% residue had an increase in the mechanical resistance when compared to those produced from the basic mass and that the formulation with 2% feldspar and residue presented the best technological properties, lowering the sintering temperature down to 1120?C
A ind?stria de cer?mica vermelha do Piau? ? bem desenvolvida e se destaca no contexto nacional pela qualidade t?cnica de seus produtos. J? a ind?stria de revestimento pouco se desenvolveu, visto que o estado possui uma ?nica empresa que produz revestimento de base argilosa vermelha. Esta tese tem por objetivo utilizar a massa b?sica predominantemente il?tica da ind?stria citada, adicionando ? mesma feldspato e/ou res?duo de caulim com o prop?sito de obter produtos de melhores qualidades t?cnicas. O res?duo caulim ? constitu?do basicamente de caulinita, mica moscovita e quartzo; o feldspato utilizado foi o pot?ssico. Para este experimento, utilizou-se a massa b?sica (MB) para controle experimental e quinze formula??es assim codificadas: F2, F4, F8, F16, F32, FR2, FR4, FR8, FR16, FR32, R2, R4, R8, R16 e R32. Todas as mat?rias-primas foram mo?das a seco, caracterizadas, formuladas, depois umidificadas a 10% com ?gua. Em seguida, foram confeccionados corpos-de-prova por prensagem uniaxial em matriz retangular de a?o (60,0 x 20,0 x 5,0) mm? a (24 MPa), os quais foram queimados em quatro temperaturas: 1080?C, 1120?C, 1160?C, com taxa de aqu ecimento de 10?C/min e patamar de 10 min em forno el?trico, e a ?ltima em forno a rolo industrial e pico de 1140?C com o objetivo de validar os resultados encontra dos em laborat?rio; por ?ltimo, foram realizados ensaios tecnol?gicos: MEA, RL, AA, PA, TRF e PF. Os mesmos mostraram que o res?duo estudado pode ser considerado como mat?riaprima de grande potencial para a ind?stria de pisos e revestimentos cer?micos de base argilosa vermelha, j? que tanto os resultados encontrados em laborat?rio como na ind?stria mostram que os corpos-de-prova produzidos a partir das formula??es com feldspato at? 4% e os produzidos com feldspato e res?duo at? 8% permitiram uma redu??o da absor??o de ?gua e aumento da resist?ncia mec?nica, sendo que os corpos-de-prova produzidos com at? 4% de res?duo tiveram aumento da resist?ncia mec?nica, quando comparados aos corpos-de-prova produzidos a partir da massa b?sica e que a formula??o com 2% de feldspato e res?duo apresentou melhores propriedades tecnol?gicas, reduzindo a temperatura de sinteriza??o para 1120?C

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Hulo, Sébastien. "Le condensat d'air exhalé : une nouvelle matrice pour évaluer l'exposition pulmonaire professionnelle." Phd thesis, Université du Droit et de la Santé - Lille II, 2014. http://tel.archives-ouvertes.fr/tel-01060978.

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Dans le cadre d'une action préventive, la mesure de la dose interne pulmonaire est plus pertinenteque la mesure de l'exposition atmosphérique car la dose interne est la quantité de toxique pouvantinteragir avec les cellules de l'épithélium respiratoire. En santé-travail, le dosage urinaire est fréquemmentutilisé mais il ne représente que le résultat final de l'épuration de multiples organes. Lecondensat d'air exhalé (EBC) est le liquide obtenu de façon non invasive après refroidissement del'air expiré d'un sujet au repos. Ce liquide est constitué de l'aérosolisation du liquide recouvrantl'épithélium respiratoire du compartiment alvéolaire et aussi du compartiment trachéobronchique oubronchique. Nous proposons d'utiliser l'EBC comme une approche alternative pour la surveillancebiologique des salariés. Les modèles cinétiques d'épuration pulmonaire actuels montrent que lesparticules déposées dans le compartiment alvéolaire ont une épuration très lente. Nous avons doncvoulu savoir si l'EBC était une matrice reflétant l'exposition pulmonaire en particules inhalées.Objectifs : 1) évaluer la faisabilité de la détection de particules minérales ou métalliques dans l'EBCde salariés exposés, 2) corréler la concentration de ces particules dans l'EBC avec les concentrationsatmosphériques de ces particules obtenues pendant le poste de travail et avec les dosages urinaires.Matériel et Méthode : Nous avons analysé les EBC de salariés issus de trois secteurs d'activitéprofessionnelle. La 1ère étude concernait un salarié d'une unité de broyage de muscovite atteintd'une infiltration pulmonaire diffuse. La 2ème étude était une étude " exposé/non-exposé "concernant un groupe de soudeurs utilisant la technique " metal inert gaz " (MIG). La 3ème étudeétait une étude " exposé/non-exposé " de salariés exposés à des composés solubles de bérylliumdans le secteur de l'aluminerie dans 2 entreprises différentes.RésultatsEtude n°1 : L'analyse minéralogique de l'EBC a retrouvé des particules ayant le même profil spectralen spectrométrie Raman que les particules prélevées dans l'atmosphère de l'entreprise. L'analyseminéralogique du parenchyme pulmonaire a montré la présence d'une concentration élevée departicules compatibles avec des particules de muscovite.Etude n°2 : Les concentrations de manganèse et de nickel dans l'EBC (Mn-EBC, Ni-EBC) dosées parICP-MS étaient significativement plus élevées chez les soudeurs que chez les témoins alors que cettedifférence n'était pas significative pour le Mn urinaire (Mn-U). Les concentrations de Mn-EBC et deNi-EBC ne sont pas corrélées avec leur concentration respective dans l'urine. Les régressionslinéaires ont trouvé des coefficients significativement positifs entre les concentrations de Mn-EBC,Ni-EBC, Ni-U et Cr-U et les indices d'exposition cumulée.Etude n°3 : Les concentrations de béryllium et d'aluminium dans l'EBC (Be-EBC, Al-EBC) étaientsignificativement plus élevées chez les sujets de l'entreprise n°1 que chez les témoins alors que leursconcentrations dans les urines ne l'étaient pas. Les régressions linéaires ont trouvé des coefficientssignificativement positifs entre les concentrations de Be-EBC et celle d'Al-EBC mais aussi entre lesconcentrations de Be-EBC et l'indice d'exposition cumulée. Les concentrations d'Al-EBC et Al-Uétaient significativement plus élevées chez les sujets de l'entreprise n°2 que chez les témoins. [...]

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48

Pröhl, Holger. "Optische Eigenschaften ultradünner PTCDA & TiOPc Einzel- und Heteroschichten." Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2007. http://nbn-resolving.de/urn:nbn:de:swb:14-1188485812048-23173.

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In der vorliegenden Arbeit werden die optischen Eigenschaften von dünnen PTCDA und TiOPc Schichten untersucht. Dies wurde mit der Kombination der Methoden der Molekularstrahlepitaxie (OMBE), der differentiellen Reflexionsspektroskopie (DRS) und Photolumineszenzmessungen möglich. Dabei steht der Übergang vom Einzelmolekül zum molekularen Festkörper im Mittelpunkt. Der realisierte optische Aufbau ermöglicht es, die optischen Eigenschaften von molekularen Sub- und Multilagen während der Schichtabscheidung im Ultrahochvakuum (UHV) zu bestimmen. Eine Strukturuntersuchung kann so unmittelbar darauf im UHV durchgeführt werden, ohne Umordnungsprozesse durch einen Probe-Luft-Kontakt zu riskieren. In dieser Arbeit wurden PTCDA-Schichten auf Muskovit-Glimmer(0001) und auf Au(100) untersucht. Auf Glimmer wird sehr gut ausgeprägtes Lagenwachstum gefunden, die Moleküle bilden auf dem schwach wechselwirkenden Substrat hochgeordnete epitaktische Filme. Dies ermöglichte für PTCDA, als quasi-eindimensionaler Molekülkristall, die optische Charakterisierung von Monomeren, Stapel-Dimeren und -Oligomeren während des Filmwachstums mittels DRS und Photolumineszenzmessungen. Die DRS-Messungen zeigen, daß die bekannten Festkörpereigenschaften schon bei Schichtdicken in der Größenordnung von 3-4 Gitterkonstanten ausgeprägt sind. Bis zu diesen Dicken sind die wesentlichen Änderungen in den optischen Eigenschaften zu beobachten. Ausgehend von Monomer-typischen Spektren entwickeln sich in dieser Dickenskale bereits alle Charakteristika der Festkörperspektren, wobei der Monomer-Dimerübergang die gravierendsten spektralen Änderungen hervorruft. Diese überraschende Tatsache war von den gängigen Theorien so nicht zu erwarten und ist Beleg für eine starke Wechselwirkung zwischen den dicht gepackten Molekülen. Steigen die Dimensionen des Films weiter, gibt es nur noch marginale Änderungen, die sich hauptsächlich in spektralen Verschiebungen äußern. Diese "finite-size" Effekte sind mit gängigen Theorien der Delokalisation der molekularen Anregung verträglich. Die Größe der Verschiebungen deutet jedoch darauf hin, daß gestalt- und dickenabhängige dielektrische Effekte gegenüber Delokalisierung und Confinement von Excitonen dominieren. Die veränderte Substratwechselwirkung auf der Au(100)-Oberfläche zeigt sich sowohl in verändertem Filmwachstum als auch abweichenden optischen Eigenschaften. Es wurde beobachtet, daß sich die Einflüsse durch die Substratbindung auf der Längenskala von nur einer Gitterkonstanten auswirken. Die PTCDA-Lagen, die auf dieser hybridisierten Grenzschichtlage wachsen, haben bereits die vom ungestörten System bekannten Eigenschaften. Da auf der Goldoberfläche mit zunehmender Schichtdicke das Inselwachstum (Stranski-Krastanov-Wachstum) überwiegt, verwischen die schichtabhängigen spektralen Änderungen zusehends. Für TiOPc auf Glimmer(0001) wurde bei Raumtemperatur amorphes Wachstum beobachtet, mit weniger gravierenden spektralen Änderungen. Jedoch sind auch in diesem System große dickenabhängige Verschiebungen in den Spektren festzustellen, die wie im Fall von PTCDA-Schichten hauptsächlich dielektrischen Effekten zugerechnet werden können. In TiOPc/PTCDA-Heteroschichten auf Glimmer konnte der Energietransfer vom PTCDA zum TiOPc auf molekularer Ebene, durch Löschung der PTCDA-Lumineszenz und anschließender sensibilisierter Emission des TiOPc, nachgewiesen werden. Dabei wurde bei sehr kleinen TiOPc-Schichtdicken die Emission von TiOPc-Monomeren beobachtet. Zusätzlich wurde eine dem Anion TiOPc- zuzurechnende Emission, als Indiz einer Ladungstrennung auf molekularer Ebene festgestellt. Bei größeren TiOPc-Schichtdicken tritt Exciplexemission auf, als Beleg für die starke Molekül-Molekül-Wechselwirkung an der Grenzfläche. Bei dickeren Schichten wird mit zunehmender Aggregation der TiOPc-Moleküle, die Lumineszenzausbeute durch Öffnung einer Reihe von nichtstrahlenden Rekombinationsmöglichkeiten, wie auch bei PTCDA beobachtet, geringer.

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49

Pröhl, Holger. "Optische Eigenschaften ultradünner PTCDA & TiOPc Einzel- und Heteroschichten: Vom Einzelmolekül zum molekularen Festkörper." Doctoral thesis, Technische Universität Dresden, 2006. https://tud.qucosa.de/id/qucosa%3A23952.

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In der vorliegenden Arbeit werden die optischen Eigenschaften von dünnen PTCDA und TiOPc Schichten untersucht. Dies wurde mit der Kombination der Methoden der Molekularstrahlepitaxie (OMBE), der differentiellen Reflexionsspektroskopie (DRS) und Photolumineszenzmessungen möglich. Dabei steht der Übergang vom Einzelmolekül zum molekularen Festkörper im Mittelpunkt. Der realisierte optische Aufbau ermöglicht es, die optischen Eigenschaften von molekularen Sub- und Multilagen während der Schichtabscheidung im Ultrahochvakuum (UHV) zu bestimmen. Eine Strukturuntersuchung kann so unmittelbar darauf im UHV durchgeführt werden, ohne Umordnungsprozesse durch einen Probe-Luft-Kontakt zu riskieren. In dieser Arbeit wurden PTCDA-Schichten auf Muskovit-Glimmer(0001) und auf Au(100) untersucht. Auf Glimmer wird sehr gut ausgeprägtes Lagenwachstum gefunden, die Moleküle bilden auf dem schwach wechselwirkenden Substrat hochgeordnete epitaktische Filme. Dies ermöglichte für PTCDA, als quasi-eindimensionaler Molekülkristall, die optische Charakterisierung von Monomeren, Stapel-Dimeren und -Oligomeren während des Filmwachstums mittels DRS und Photolumineszenzmessungen. Die DRS-Messungen zeigen, daß die bekannten Festkörpereigenschaften schon bei Schichtdicken in der Größenordnung von 3-4 Gitterkonstanten ausgeprägt sind. Bis zu diesen Dicken sind die wesentlichen Änderungen in den optischen Eigenschaften zu beobachten. Ausgehend von Monomer-typischen Spektren entwickeln sich in dieser Dickenskale bereits alle Charakteristika der Festkörperspektren, wobei der Monomer-Dimerübergang die gravierendsten spektralen Änderungen hervorruft. Diese überraschende Tatsache war von den gängigen Theorien so nicht zu erwarten und ist Beleg für eine starke Wechselwirkung zwischen den dicht gepackten Molekülen. Steigen die Dimensionen des Films weiter, gibt es nur noch marginale Änderungen, die sich hauptsächlich in spektralen Verschiebungen äußern. Diese "finite-size" Effekte sind mit gängigen Theorien der Delokalisation der molekularen Anregung verträglich. Die Größe der Verschiebungen deutet jedoch darauf hin, daß gestalt- und dickenabhängige dielektrische Effekte gegenüber Delokalisierung und Confinement von Excitonen dominieren. Die veränderte Substratwechselwirkung auf der Au(100)-Oberfläche zeigt sich sowohl in verändertem Filmwachstum als auch abweichenden optischen Eigenschaften. Es wurde beobachtet, daß sich die Einflüsse durch die Substratbindung auf der Längenskala von nur einer Gitterkonstanten auswirken. Die PTCDA-Lagen, die auf dieser hybridisierten Grenzschichtlage wachsen, haben bereits die vom ungestörten System bekannten Eigenschaften. Da auf der Goldoberfläche mit zunehmender Schichtdicke das Inselwachstum (Stranski-Krastanov-Wachstum) überwiegt, verwischen die schichtabhängigen spektralen Änderungen zusehends. Für TiOPc auf Glimmer(0001) wurde bei Raumtemperatur amorphes Wachstum beobachtet, mit weniger gravierenden spektralen Änderungen. Jedoch sind auch in diesem System große dickenabhängige Verschiebungen in den Spektren festzustellen, die wie im Fall von PTCDA-Schichten hauptsächlich dielektrischen Effekten zugerechnet werden können. In TiOPc/PTCDA-Heteroschichten auf Glimmer konnte der Energietransfer vom PTCDA zum TiOPc auf molekularer Ebene, durch Löschung der PTCDA-Lumineszenz und anschließender sensibilisierter Emission des TiOPc, nachgewiesen werden. Dabei wurde bei sehr kleinen TiOPc-Schichtdicken die Emission von TiOPc-Monomeren beobachtet. Zusätzlich wurde eine dem Anion TiOPc- zuzurechnende Emission, als Indiz einer Ladungstrennung auf molekularer Ebene festgestellt. Bei größeren TiOPc-Schichtdicken tritt Exciplexemission auf, als Beleg für die starke Molekül-Molekül-Wechselwirkung an der Grenzfläche. Bei dickeren Schichten wird mit zunehmender Aggregation der TiOPc-Moleküle, die Lumineszenzausbeute durch Öffnung einer Reihe von nichtstrahlenden Rekombinationsmöglichkeiten, wie auch bei PTCDA beobachtet, geringer.

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50

Kankate, Laxman. "Light emitting organic nanofibers from para-phenylene and alpha-thiophene oligomers." Doctoral thesis, Humboldt-Universität zu Berlin, Mathematisch-Naturwissenschaftliche Fakultät I, 2008. http://dx.doi.org/10.18452/15775.

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Wir haben blau, grün und orange leuchtende organische Nanofäden oder Nanonadeln und Mikroringe aus para-Hexaphenyl (p-6P), alpha-Quaterthiophen (alpha-4T) und alpha-Sexithiophen (alpha-6T) mittels Organischer Molekularstrahlepitaxie (OMBE) auf Muskovit Glimmer hergestellt. Die Aggregate haben wir mit der Atomkraftmikroskopie, mit der Fluoreszenz-Mikroskopie und durch UV-vis Spektroskopie charakterisiert. Auf der Muskovit Oberfläche wachsen p-6P Fäden parallel zueinander auf und zeigen zwei verschiedene Orientierungsdomänen entlang [110] und [1-10]. Mit Hilfe einer systematischen statistischen Analyse diskutieren wir das Wachstum dieser p-6P Nadeln für verschiedene Wachstumsbedingungen. Zusätzlich zu den Fäden haben wir p-6P Cluster auf der Oberfläche beobachtet. Nadeln werden durch die Aggregation solcher Cluster gebildet. Ein Realraummodell der Morphologie der Nadeln sowie ein Modell für deren Wachstum werden vorgestellt. Indem wir Glimmer zunächst mit einer dünnen Goldschicht bedecken und die Wachstumsparameter variieren, erreichen wir eine weitgehende Kontrolle der Morphologie der Nadeln (Länge von 0,5 Mikrometer bis 1 mm, Höhe von 25 bis 300 nm und Breite von 100 bis 600 nm). Im Gegensatz zu p-6P orientieren Thiophene ihre Wachstumsrichtungen an allen hoch symmetrischen Richtungen von Glimmer. Es wird gezeigt, dass die Mechanismen für das Fadenwachstum von beiden Oligomere gleich sind, nämlich eine Kombination aus Epitaxie und einer Dipol-unterstützten Ausrichtung. Auch die Strukturen dieser Fäden sind ähnlich: die Moleküle liegen parallel angeordnet auf der Oberfläche, ihre Längsachsen orientieren sich schräg zur Längsachse der Fäden. Auf mit Wasser oder Methanol vorbehandeltem Glimmer wachsen diese beiden Oligomere als gebogene Fäden und Mikroringe auf. Diese Oberflächenvorbehandlungen sowie das Wachstum von p-6P auf Gold/Glimmer unterstützen auch den Wachstumsmechanismus auf der sauberen Glimmer-Oberfläche.
By using organic molecular beam epitaxy (OMBE) blue, green and orange light emitting organic nanofibers or nanoneedles and microrings from para-hexaphenyl (p-6P), alpha-quaterthiophene (alpha-4T) and alpha-sexithiophene (alpha-6T), respectively, on muscovite mica surfaces are generated. The aggregates are characterized by atomic force microscopy, fluorescence microscopy and UV-vis spectroscopy. On muscovite mica, p-6P fibers usually grow mutually parallel showing two domains of their orientations with an angle of 120 degree in between. The detail growth of nanofibers from p-6P by performing a systematic statistical analysis of fibers as a function of various growth conditions is discussed. Furthermore, the morphology exhibits p-6P clusters, which are found to be fibers´ building blocks. A real space model of the fiber and a model for their growth are also presented. By introducing a thin gold layer on mica prior to p-6P deposition together with varying growth parameters, the morphology of fibers is controlled in a wide range (length from 0.5 micrometer to 1 mm, height from 25 to 300 nm and width from 100 to 600 nm). In contrast to p-6P, thiophene fibers exhibit various orientations close to mica high symmetry directions. It is shown that the mechanism behind the fiber growth from all molecules on mica is the same, i.e. a combination of epitaxy and dipole assisted growth process. The fiber microscopic structures are similar, too: molecules take lying orientations and they hold themselves parallel pointing their long axes along an oblique direction off the long fiber axis. The growth of both types of oligomers on water or methanol treated mica surfaces leads to the formation of bent fibers and microrings. This surface pretreatment and the growth of p-6P on gold/mica support the fiber growth mechanism on plain mica.

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