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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
381

Akumulace těžkých kovů v tkáních bezobratlých živočichů na struskopopílkových odkalištích / Accumulation of heavy metals in tissues of terrestrial arthropods at fly ash deposits

Mengr, Jan January 2017 (has links)
No description available.
382

Akumulace těžkých kovů v tkáních bezobratlých živočichů na struskopopílkových odkalištích / Accumulation of heavy metals in tissues of terrestrial arthropods at fly ash deposits

Mengr, Jan January 2017 (has links)
No description available.
383

A Palaeoproterozoic high-sulphidation epithermal gold deposit at Orivesi, southern Finland

Kinnunen, A. (Aulis) 06 May 2008 (has links)
Abstract The metamorphosed Palaeoproterozoic Orivesi gold deposit in southern Finland is located within the Tampere Schist Belt, which belongs to the Svecofennian domain. The Orivesi mine, run by Outokumpu Mining Oy, was in production from 1994 to 2003, during which time a total of approximately 1.7 million tons of ore was extracted, with an Au content of 9.31 g/t, implying a total output 13.115 tons of gold in concentrate. The hydrothermal alteration halo can be divided successively into chlorite-dominant, sericite-dominant and quartz-dominant rocks from the outer zone inwards. The host rocks of the ore are quartz rocks with andalusite-rich quartz rocks. Topaz-bearing rocks also occur in the inner part of the alteration halo. In addition to Au, the elements Ag, Te, Bi, Sb, S, As, Se, Cu, Zn, Pb, Sn and Mo are enriched to varying degrees within the alteration halo. The main ore minerals include base metal sulphides, sulphosalts and tellurides. Pyrite is the most common sulphide. The sulphosalts are represented by tetrahedrite, bournonite, boulangerite and meneghinite. The most common gold, gold-silver and silver tellurides are calaverite, montbrayite, petzite, kostovite, sylvanite and hessite. Other known tellurides include tellurobismuthite, altaite, melonite, frohbergite, tsumoite, tetradymite and rucklidgeite. Gold occurs mostly in fine-grained native grains containing an average of 5% Ag. The native gold is usually of very small grain size, generally < 20 µm. Most of the gold grains in the deposit occur as intergrowths with tellurides. The adjacent hypabyssal intrusion is an obvious source of both hydrothermal fluids and metals. A comb quartz layering has been discovered in the transition zone between the intrusion and the alteration halo. The Orivesi deposit is thought to belong to the high-sulphidation epithermal type. Soon after its formation the deposit encountered deformation and metamorphism that amounted to lower amphibolite facies conditions. The subsequent retrograde metamorphism caused the reappearance of some hydrothermal minerals typical of high-sulphidation epithermal deposits.
384

Les dépôts d’objets pariétaux des grottes ornées au Paléolithique supérieur : gestes, comportements symboliques, cultures / The parietal deposits of objects in decorated caves in the upper Palaeolithic : gestures, symbolic behavior, cultures

Peyroux, Magali 06 July 2012 (has links)
Les grottes sont un environnement particulier aux propriétés géophysiques singulières. C’est un milieu qui offre une conservation exceptionnelle et dans lequel s’inscrit, dans la matrice minérale, la marque du moindre geste qui y est réalisé. Assidument fréquentées au Paléolithique supérieur, de nombreuses cavités renferment des témoignages variés du passage des hommes. L’art pariétal est un des témoins, parfois spectaculaire, de cette fréquentation. D’autres vestiges (marques, objets, aménagements…) y sont aussi observables. Souvent moins visibles, moins spectaculaires car faisant entrer en jeu des éléments plus communs, l’intérêt de ces vestiges, dans la compréhension des comportements préhistoriques, a été reconnu tardivement dans l’histoire de la discipline. Parmi ces diverses traces d’activités humaines, et faisant suite aux travaux initiateurs sur le sujet (Bégouën et Clottes, 1981 ; Clottes 2007 et 2009), nous nous intéressons ici aux dépôts d’objets en paroi. Aucune étude approfondie et croisée à grande échelle de ce phénomène n’avait été conduite jusqu’ici. Les différentes matérialisations de ces gestes de dépôts, leurs constituants fondamentaux, les cultures et les territoires concernés ainsi que l’approfondissement de la connaissance des comportements humains en grottes ornées au travers de l’étude de ces gestes ont été les principaux axes de notre recherche.Nous avons ainsi identifié la présence de ces gestes de dépôts dans une quarantaine de sites ornés répartis sur l’espace franco-cantabrique durant tout le Paléolithique supérieur. Nous avons essentiellement basé la construction de notre méthode d’étude et notre analyse sur l’étude exhaustive et contextualisée de ces dépôts dans six sites français : Blanchard, Foissac, Gargas inférieure, Gargas supérieure, Le Mammouth et Le Pigeonnier. La priorité était pour nous de proposer une lecture interprétative des comportements à l’origine de ces dépôts. La matière dure animale (à l’état de fragments), et dans une moindre mesure le silex et l’ocre, sont les éléments essentiellement constitutifs de ces dépôts. Les résultats montrent que ces derniers sont omniprésents dans les grottes ornées. Ils ne sont cependant pas tous en tout point comparable. Nous avons pu mettre en évidence différentes catégories de gestes de dépôts. La plupart sont intentionnels mais sous-tendus par des motivations distinctes (symbolique, pragmatique, personnelle…). Nous avons identifié quatre pratiques symboliques où le dépôt est un medium permettant une connexion (« reliance ») avec l’Invisible par l’intermédiaire de la paroi-réceptacle.Ces pratiques (très fréquemment observées au Magdalénien et au Gravettien) sont des comportements symboliques fondamentaux qui motivent la fréquentation des cavités par ces populations préhistoriques durant tout le Paléolithique supérieur. Elles sont intimement reliées aux modes de vie, aux traditions culturelles et à la cosmogonie des sociétés préhistoriques. Ces pratiques préhistoriques peuvent être envisagées selon l’idée d’une possible affiliation à certains des grands universaux qui participent du fonds commun symbolique, et même spirituel, de l’humanité. / Caves are a particular environment with singular geophysics properties. It is an environment which offers an exceptional preservation and in which registers, in the mineral matrix, the mark of the slightest gesture which is realized there. Assidument frequented in the upper Palaeolithic, numerous cavities contain varied vestiges of the human passage.The parietal Art is one of the marks, sometimes spectacular, of this frequentation.Other vestiges (marks, objects, arrangements…) are there also observable. Often less visible, less spectacular because using more common elements, the interest of these vestiges, in the understanding of the prehistoric behavior, was late recognized in the history of the discipline. Among these diverse tracks of human activities, and following upon the works initiators on the subject (Bégouën et Clottes, 1981 ; Clottes 2007 et 2009), we are interested here in the deposits of objects in rock face. No in-depth and crossed study on a large scale of this phenomenon had been led up to here.The various realizations of these gestures of deposits, their fundamental constituents, the cultures and the concerned territories as well as the deepening of the knowledge of the human behavior in decorated caves through the study of these gestures were the main axes of our research.We so identified the presence of these gestures of deposits in about forty decorated sites distributed on the French-Catabric space during all the upper Palaeolithic. We essentially based the construction of our method of study and our analysis on the exhaustive and contextualised study of these deposits in six French sites : Blanchard, Foissac, Gargas inférieure, Gargas supérieure, Le Mammouth et Le Pigeonnier. The priority was for us to propose an interpretative reading of the behavior at the origin of these deposits. The animal hard material (in the state of fragments), and to a lesser extent the flint and the ochre, are the essentially constituent elements of these deposits. The results show that these last ones are omnipresent in the decorated caves. They are not however all completely comparable. We were able to bring to light various categories of gestures of deposits. Most are deliberate but underlain by different motivations (symbolic, pragmatic, personal…). We identified four symbolic practices where the deposit is a medium allowing a connection (« reliance ») with the Invisible through the rock face - receptacle.These practices (very frequently observed in the Magdalenian and in the Gravettian) are fundamental symbolic behavior which motivate the frequentation of cavities by these prehistoric populations during all the upper Palaeolithic. They are intimately bound with the lifestyles, with the cultural traditions and with the cosmogony of the prehistoric societies. These prehistoric practices can be envisaged according to the idea of a possible affiliation in some of the big universals which participate in the symbolic common fund, and even spiritual, in the humanity.
385

Untersuchung und Modellierung der Bildung partikulärer Ablagerungen in Trinkwasserverteilungsnetzen

Ripl, Klaus 31 May 2017 (has links) (PDF)
Das Auftreten von Braunwasser in Trinkwasserverteilungsnetzen ist eine Beeinträchtigung der Trinkwasserqualität, die durch mobilisierte partikuläre Ablagerungen verursacht wird. Die Partikel gelangen durch verschiedene Prozesse, wie z. B. der Korrosion metallischer Leitungen und den Eintrag am Wasserwerk, kontinuierlich in sehr geringen Massenströmen in das Rohrnetz. Durch die Akkumulation der Partikel an Rohroberflächen können sich Ablagerungsmengen bilden, die bei ansteigenden Strömungsgeschwindigkeiten resuspendiert werden und zu unerwünschten Braunwassererscheinungen führen. Die vorliegende Arbeit behandelt die experimentelle Untersuchung des Transportes von Partikeln, die für Trinkwassernetze typisch sind, in Rohrströmungen. Es werden Einflussfaktoren identifiziert, die für den Partikeltransport von Bedeutung sind. Ein neu entwickeltes dynamisches Modell beschreibt den Transport von Partikeln und die Ablagerungsbildung in Rohrströmungen und vermaschten Rohrnetzen. Das Modell wurde in einer Anwendersoftware implementiert und an einem Trinkwasserverteilungsnetz für das Nachvollziehen der beobachteten Ablagerungsbildung eingesetzt. Im Vergleich zu bestehenden dynamischen Modellen werden partikelbezogene Prozesse unter Berücksichtigung der für trinkwasserbürtige Partikel und Ablagerungen typischen Eigenschaften mathematisch genauer beschrieben. Stationäre und dynamische Ereignisse bezüglich Wasserqualität und Ablagerungsbildung können jetzt durch die Berücksichtung zahlreicher zeitabhängiger Einflussfaktoren nachvollzogen werden. / The occurrence of discoloured water in drinking water distribution systems is a disturbance of the water quality, which is induced by mobilised particulate deposits. Different processes result in the continuous entry of small mass flow rates of particles into the piping, for instance the corrosion of metallic pipes as well as the entry at the water works outlet. By the accumulation of these particles, significant amounts of deposits can be formed and at higher flow rates be resuspended, which leads to unwanted events with discoloured water. This study examines the experimental investigation of the transport of particles, which are typical for drinking water distribution systems, in pipe flow. Influencing factors are identified, which are of importance for the particle transport. With a newly developed model, the transport of particles and the deposit formation in pipe flow and in piping is described. The model is implemented into a software application and deployed at a drinking water distribution system to understand the observed deposit formation. In comparison with existent dynamic water quality models, particle-related processes are described mathematically in more details, under consideration of characteristics typical for particles and deposits in drinking water distribution systems. Hence, observed steady-state and dynamic events can be followed using several influencing time-dependent factors.
386

Geologically-constrained UBC–GIF gravity and magnetic inversions with examples from the Agnew-Wiluna greenstone belt, Western Australia

Williams, Nicholas Cory 05 1900 (has links)
Geologically-constrained inversion of geophysical data is a powerful method for predicting geology beneath cover. The process seeks 3D physical property models that are consistent with the geology and explain measured geophysical responses. The recovered models can guide mineral explorers to prospective host rocks, structures, alteration and mineralisation. This thesis provides a comprehensive analysis of how the University of British Columbia Geophysical Inversion Facility (UBC–GIF) gravity and magnetic inversions can be applied to subsurface mapping and exploration by demonstrating the necessary approach, data types, and typical results. The non-uniqueness of inversion demands that geological information be included. Commonly available geological data, including structural and physical property measurements, mapping, drilling, and 3D interpretations, can be translated into appropriate inversion constraints using tools developed herein. Surface information provides the greatest improvement in the reliability of recovered models; drilling information enhances resolution at depth. The process used to prepare inversions is as important as the geological constraints themselves. Use of a systematic workflow, as developed in this study, minimises any introduced ambiguity. Key steps include defining the problem, preparing the data, setting inversion parameters and developing geological constraints. Once reliable physical property models are recovered they must be interpreted in a geological context. Where alteration and mineralisation occupy significant volumes, the mineralogy associated with the physical properties can be identified; otherwise a lithological classification of the properties can be applied. This approach is used to develop predictive 3D lithological maps from geologically-constrained gravity and magnetic inversions at several scales in the Agnew-Wiluna greenstone belt in Australia’s Yilgarn Craton. These maps indicate a spatial correlation between thick mafic-ultramafic rock packages and gold deposit locations, suggesting a shared structural control. The maps also identify structural geometries and relationships consistent with the published regional tectonic framework. Geophysical inversion provides a framework into which geological and geophysical data sets can be integrated to produce a holistic prediction of the subsurface. The best possible result is one that cannot be dismissed as inconsistent with some piece of geological knowledge. Such a model can only be recovered by including all available geological knowledge using a consistent workflow process. / Science, Faculty of / Earth, Ocean and Atmospheric Sciences, Department of / Graduate
387

Hydrothermal Fe-Carbonate Alteration Associated with Volcanogenic Massive Sulfide (VMS) Deposits in Cycle IV of the Noranda Mining Camp, Rouyn-Noranda, Quebec

Wilson, Ryan January 2012 (has links)
Massive sulfide deposits in the Noranda mining camp, northwestern Québec, are mainly associated with extensive footwall alteration defined by intense chloritization and sericitization. However, Fe-carbonate alteration also occurs in proximity to some deposits. To test the exploration significance of carbonate alteration in the camp, two areas of intense carbonate alteration were examined, around the small Delbridge deposit and near the new Pinkos occurrence in the Cyprus Rhyolite. Between 1969 and 1971, the Delbridge deposit produced 370,000 t of ore grading 9.6% Zn, 0.61% Cu, 110 g/t Ag, and 2.1 g/t Au. Recent drilling at the new Pinkos occurrence intersected 2.64 m of massive to semi-massive sulfides grading 8.1% Zn and 18.2 g/t Ag. Alteration mapping has shown that the distribution of Fe-carbonates can be used to identify vertically extensive zones of hydrothermal upflow at both properties. At Delbridge, intense Fe-carbonate alteration in brecciated rhyolite defines a pipe-like upflow zone that extends vertically for up to 300 m within the stratigraphic footwall of the massive sulfides and 100 m into the hanging wall. The location of known massive sulfide mineralization coincides with the intersection of the alteration pipe and a favorable horizon marked by the occurrence of fine-grained volcaniclastic rocks. At Pinkos, a similar zone of Fe-carbonate alteration occurs in outcrops of coherent rhyolite. Fe-carbonate alteration is most intensely developed along polygonal cooling fractures in massive rhyolite and decreases in intensity towards the centers of the columns. Fe-carbonate stringers and locally abundant matrix carbonate occur in fragmental rocks at the stratigraphic top of the coherent rhyolite flows and are most intense at the location of sulfide-bearing outcrops that mark the known mineralized horizon. Whereas Fe-carbonate alteration defines the central part of the hydrothermal upflow zones at both properties, disseminated pyrite occurs at the margins and is widespread outside the main upflow zones. This may indicate that Fe-carbonate in the main upflow zones formed at the expense of earlier disseminated sulfides. Replacement of pyrite by synvolcanic Fe-carbonate alteration at Delbridge and Pinkos can probably be attributed to a relatively high concentration of dissolved CO2, possibly of magmatic origin, in the main-stage ore-forming fluids.
388

Komparace koupě a vkladu obchodního závodu (účetní řešení) / Comparison of the purchase and deposit business establishment (accounting solution)

Zelená, Michaela January 2015 (has links)
This thesis deals with comparison of the purchase and deposit business establishment in accounting terms. This task deals with the legal definition of the purchase and deposit business establishment after the recodification of Czech private law, which is valid from 1st of January 2014. When there have been several changes, which relate to just purchase and deposit business establishment. The terminology has changed, instead the company used establishment. The basic theme of this thesis is the accounting treatment for the purchase and deposit business establishment both in terms of general concepts and Czech accounting standards. The application part is dedicated to the accounting treatment of the mentioned transactions in accordance with international financial reporting standards and Czech accounting standards. Keywords: purchase of the business establishment, deposit business establishment, recodification, accounting, IFRS, Czech accounting standards
389

Nanopatterned polymer brushes by reactive writing

Nawroth, Jonas F., Neisser, Claudia, Erbe, Artur, Jordan, Rainer 13 January 2017 (has links)
Polymer brush patterns were prepared by a combination of electron beam induced damage in self-assembled monolayers (SAMs), creating a stable carbonaceous deposit, and consecutive self-initiated photografting and photopolymerization (SIPGP). This newly applied technique, reactive writing (RW), is investigated with 1H,1H,2H,2H-perfluorooctyltriethoxysilane SAM (PF-SAM) on silicon oxide, which, when modified by RW, can be selectively functionalized by SIPGP. With the monomer N,N-dimethylaminoethyl methacrylate (DMAEMA), we demonstrate the straightforward formation of polymer brush gradients and single polymer lines of sub-100 nm lateral dimensions, with high contrast to the PF-SAM background. The lithography parameters acceleration voltage, irradiation dose, beam current and dwell time were systematically varied to identify the optimal conditions for the maximum conversion of the SAM into a carbonaceous deposit. The results of this approach were compared to patterns prepared by carbon templating (CT) under analogous conditions, revealing a dwell time dependency, which differs from earlier reports. This new technique expands the range of CT by giving the opportunity to not only vary the chemistry of the created polymer patterns with monomer choice but also vary the chemistry of the surrounding substrate.
390

Vyhodnocení dopadu bankovní regulace na stabilitu bankovního sektoru v členských státech EU ze střední a východní Evropy / Evaluation of the Impact of Banking Regulation on the Stability of Banking Sector in CEE EU Members

Wang, Mengyao January 2021 (has links)
The thesis studies the impact of European banking regulatory reforms on the stability of Central and Eastern European countries after the financial crisis with the annual data from Hungary, Poland, Slovakia, and Slovenia from 2009 to 2019. The thesis reaches several conclusions. Firstly, increasing minimum Tier 1 capital adequacy ratio through CRR/CRD IV did not significantly promote the bank stability in sample countries. However, total capital adequacy ratio is found to have positive and significant association with overall insolvency risk. Secondly, relaxing restrictions would have negative impact on bank stability measured by bank z-score. Thirdly, countries that are more open on the regulation may have more stable banks, while tighter entry restrictions boost bank fragility. Fourthly, when only taking deposit insurance variables as explanatory variables, increasing the level of deposit insurance coverage may dampen the bank stability. However, when controlling other regulation and supervision indexes, the results do not show any significant effect of deposit insurance scheme on bank z-score. Lastly, the supervisory variables are not significantly associated with bank stability in sample countries.

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