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Dissertations / Theses on the topic 'LODE'

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Published: 4 June 2021
Last updated: 21 February 2023

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1

Charles, Llorens Joan Josep. "Evaluación crítica del modelo directivo LODE (1985)." Doctoral thesis, Universitat de Barcelona, 2009. http://hdl.handle.net/10803/1372.

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La presente investigación en forma de tesis doctoral, pretende ser una reflexión rigurosa acerca de las fortalezas y debilidades del modelo directivo de los centros educativos españoles de primaria y secundaria, así como una prospección realista y completa acerca de la manera en que debería ser implementado un hipotético modelo directivo profesional de centros educativos en el contexto social y educativo español.
The present research in the form of a doctoral thesis, is intended to be a rigorous reflection about the strengths and weaknesses of the managerial educational model in Spain, both in primary and secondary schools. Besides, it tries to give a realistic and complete view on the way how to implement a hypothetical model of professional management in schools within the social and educacional Spanish context.
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2

Troschke-Meurer, Sascha [Verfasser], Holger [Akademischer Betreuer] Lode, Holger [Gutachter] Lode, and Peter [Gutachter] Lode. "Immunmodulatorische und genetische Parameter als prognostische Marker für das Ansprechen einer GD2-gerichteten Immuntherapie in Kombination mit Interleukin-2 bei Patienten mit Hochrisikoneuroblastom / Sascha Troschke-Meurer ; Gutachter: Holger Lode, Peter Lode ; Betreuer: Holger Lode." Greifswald : Universität Greifswald, 2020. http://d-nb.info/1221271040/34.

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3

Endres, Stefanie [Verfasser], Holger [Akademischer Betreuer] Lode, Holger [Gutachter] Lode, and Patrick [Gutachter] Hundsdörfer. "Pharmakokinetik und -dynamik einer Langzeitinfusion mit dem anti-GD2 Antikörper ch14.18/CHO bei Patienten mit einem Hochrisiko-Neuroblastom / Stefanie Endres ; Gutachter: Holger Lode, Patrick Hundsdörfer ; Betreuer: Holger Lode." Greifswald : Universität Greifswald, 2021. http://d-nb.info/1231434694/34.

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4

Moreby, R. G. "Planning and control of the environment in multi-level, narrow lode mines." Thesis, University of Exeter, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.379261.

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5

Hunt, Joan. "Mining a rich lode : The making of the Springdallah Deep Lead Goldfield communities." Thesis, Federation University Australia, 2016. http://researchonline.federation.edu.au/vital/access/HandleResolver/1959.17/102931.

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Although little material evidence survives other than mullock heaps and the occasional ruined building, a large body of archival documentation exists to help reveal the history of the deep lead gold mining communities at Springdallah. This thesis reconstructs the discovery, rise and progress of that goldfield, 30km south-west of Ballarat, through a study of family formation and community building, facilitated by micro-study tools including prosopographical and genealogical databases. At its prosperous and productive peak in the 1860s and 1870s, the communities relied totally on the mining industry for their existence. This thesis positions the alluvial deep lead gold mining industry firmly within the long but disparate historiography of Australian, and particularly Victorian, gold seeking. Unlike the many regional histories that celebrate the growth from goldfields to city status, it focuses on the miners who worked the deep leads of buried river beds, and how they and their families effected material and social change to benefit the communities they created. The findings of this thesis reveal that, in contrast to the strong Cornish presence on many Victorian goldfields, miners at Springdallah came mainly from northern England, south-west Ireland, and the lowlands of Scotland, often with extensive kinship networks. The study demonstrates that this network of communities attracted workers, usually with coal and lead mining experience, who had skills suited to conditions in the deep lead alluvial gold mining industry. According to the findings of this thesis, miners gained power within the Springdallah communities by becoming members of committees, councils, and boards of local and wider institutions. This study found that the Springdallah families were youthful, adapted well to their changed circumstances, were agents of change within their communities, and quickly took advantage of Victorian land legislation, particularly the 1869 Land Act, to take up farming properties both locally and in the north and east of the State.
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6

Reinhold, Sylvia Caroline [Verfasser], Holger [Akademischer Betreuer] Lode, Holger [Gutachter] Lode, and James F. [Gutachter] Beck. "Einfluss der Transfusionsdynamik auf Entstehung und Outcome der Nekrotisierenden Enterokolitis bei enteral ernährten „Very-Low-Birth-Weight“-Frühgeborenen (<1500g) / Sylvia Caroline Reinhold ; Gutachter: Holger Lode, James F. Beck ; Betreuer: Holger Lode." Greifswald : Universität Greifswald, 2019. http://d-nb.info/1188409077/34.

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7

Reinhold, Sylvia Caroline Verfasser], Holger [Akademischer Betreuer] [Lode, Holger [Gutachter] Lode, and James F. [Gutachter] Beck. "Einfluss der Transfusionsdynamik auf Entstehung und Outcome der Nekrotisierenden Enterokolitis bei enteral ernährten „Very-Low-Birth-Weight“-Frühgeborenen (<1500g) / Sylvia Caroline Reinhold ; Gutachter: Holger Lode, James F. Beck ; Betreuer: Holger Lode." Greifswald : Universität Greifswald, 2019. http://d-nb.info/1188409077/34.

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8

Jensen, Christian Verfasser], Holger [Akademischer Betreuer] [Lode, Holger [Gutachter] Lode, and Patrick [Gutachter] Hundsdörfer. "Impact of FCGR Polymorphisms and KIR/HLA Mismatch on outcome following Immunotherapy of Neuroblastoma patients with ch14.18/CHO combination with IL-2 / Christian Jensen ; Gutachter: Holger Lode, Patrick Hundsdörfer ; Betreuer: Holger Lode." Greifswald : Universität Greifswald, 2019. http://d-nb.info/1181326400/34.

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9

Ball, Mathew C. N. "Geology of the McDame gold camp, Cassiar, British Columbia, implications for lode-gold metallogenesis." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp04/nq22444.pdf.

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10

Akwinga, Asaah Victor [Verfasser]. "Lode gold mineralisation in the Neoproterozoic granitoids of Batouri, southeastern Cameroon / Asaah Victor Akwinga." Clausthal-Zellerfeld : Universitätsbibliothek Clausthal, 2010. http://d-nb.info/1004357818/34.

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11

Pfeffer, Tobias [Verfasser], and Lode [Akademischer Betreuer] Pollet. "Homotopy and renormalization group approaches for strongly correlated systems / Tobias Pfeffer ; Betreuer: Lode Pollet." München : Universitätsbibliothek der Ludwig-Maximilians-Universität, 2019. http://d-nb.info/1178324095/34.

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12

Holl, C. J. "A paragenetic study of the complex polymetallisation of South Lode, Wheal Jane mine, Cornwall." Thesis, University of Exeter, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.279011.

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13

Stermann, Alexander [Verfasser], N. [Akademischer Betreuer] Lode, Lockau [Akademischer Betreuer], and Schramm [Akademischer Betreuer]. "MYCN-DNA-Vakzine zur Behandlung des Neuroblastoms / Alexander Stermann. Gutachter: N. Lode ; Lockau ; Schramm." Berlin : Humboldt Universität zu Berlin, Mathematisch-Naturwissenschaftliche Fakultät I, 2014. http://d-nb.info/1047145472/34.

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14

Defaisse, Clément. "Étude de la rupture ductile d'un acier à très haute résistance pour des applications aéronautiques." Thesis, Paris Sciences et Lettres (ComUE), 2018. http://www.theses.fr/2018PSLEM010/document.

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Les pièces des structures aéronautiques telles que les arbres des turboréacteurs, les roues, les freins ou les trains d’atterrissage sont fabriquées avec des aciers à très haute résistance. Leur structure martensitique, renforcée par des précipités de taille inférieure au micromètre, confère à ces aciers une excellente résistance : leur limite d'élasticité peut dépasser les 1900 MPa et leur résistance mécanique atteindre les 2300 MPa. Ces matériaux sont choisis pour ces excellentes propriétés mécaniques sur la base de leur comportement en traction. Toutefois, leur déformation à striction (maximum de la charge) est de quelques pourcents seulement. Les méthodes de dimensionnement sous chargement critique actuelles considèrent qu’aucun point de la structure ne doit être soumis à une déformation supérieure à la déformation à striction. Ce type d’approche est ici très conservatrice puisque les aciers THR continuent de se déformer plastiquement, ceci jusqu’à plusieurs dizaines de pourcent après le début de la striction. L’objet de ces travaux est de définir un modèle d’amorçage de la rupture applicable au dimensionnement de ces structures pour un acier type : le ML340. Ce matériau est actuellement utilisé dans les arbres de turboréacteur LEAP.Le comportement élasto-plastique du matériau a été étudié grâce à des essais menés sur différents types d’éprouvettes : tractions lisses, axisymétriques entaillées, déformation plane, plates entaillées, traction-torsion. Un modèle simple de von Mises à écrouissage isotrope permet de reproduire l’ensemble de la base. Ce modèle est ajusté sur les essais de traction pour lesquels un suivi optique de la variation du diamètre minium a été mis en place. La loi d’ ́écrouissage est ensuite ajustée en prenant en compte à la fois l'élongation et la variation du diamètre. On montre en particulier que l'extrapolation du comportement, méthode consistant à prolonger les données obtenues avant l'apparition de la striction, peut conduire à une mauvaise prédiction du comportement des éprouvettes.La base expérimentale a également été employée pour étudier l’amorçage de la rupture. L’observation des faciès montre un mode de rupture ductile avec des cupules fines. Cependant, l'initiation est brutale pour tous les essais et le développement de l’endommagement en volume reste très limité, voire nul. Ces constatations conduisent à proposer l’emploi d’un critère d’amorçage découplé : ce modèle fait intervenir la triaxialité des contraintes et le paramètre de Lode. Cette double dépendance est nécessaire pour bien décrire la rupture sur toute la base expérimentale. L’identification des paramètres du modèle se base sur l'évaluation des champs mécaniques à partir des simulations élasto-plastiques par éléments finis représentant les essais. Le modèle est également capable de prédire les emplacements des points d’amorçages observés, ces informations peuvent être utilisées pour ajuster plus finement le modèle
Aeronautical structures such as jet engines shafts, wheels, brakes or landing gears are made of Ultra High Strenth Steels (UHSS). Due to their hard martensitic matrix reinforced with second phase particles, such steels exhibit extreme mechanical resistance, their yield strength can overcome 1900 MPa and their ultimate tensile strength can reach 2300 MPa. Such materials are selected based on their tensile properties, however strain at necking (maximum load) is only few percent. Conventional certified design methods assume that failure occurs when a given point of the structure reaches this strain. Regarding UHSS this approach is very conservative; those materials are still able to bear large strains after necking start. The aim of this work is to define a failure initiation model able to predict ductile failure of such structures for extremes loadings. The ML340 steel, material of LEAP jet-engine shafts, have been selected for this study.Elasto-plastic behavior is investigated with various mechanical tests. Uniaxial tensile test were performed on round bars specimens, either smooth or notch, and flat specimens, either u notched or plane strain. Traction/torsion and compression/torsion biaxial tests were performed on tubes specimens. A simple isotropic von Mises plasticity model was found sufficient to describe mechanical behavior of this experimental database. This model was calibrated based on round smooth tensile tests, a longitudinal extensometer and a non contact method, measuring diameter reduction, were used in order to monitor strains. Hardening law was adjust with both sets of data using a reverse method, hence material striction is take into account during the identification. Identification method extrapolating plastic behavior based on tensile data measured before the striction begining is shown to overperdict plastic behavior.Failure initiation was also investigated through fracture tests. Every fractography display very fine dimples related to ductile fracture, however fracture apears to be very brutal and very few damage was observed underneath fracture surface. As a result an uncoupled fracture initiation model is proposed, damage indicator is driven by both stress triaxiality and a Lode parameter. This dual dependency is necessary in order to represent fracture for the whole database. Model parameters identification relies on the evaluation of local stress state for each test, this could be achieved with 3D elasto-plastic simulations. As a result fracture model was able to predict correct fracture initiation point positions observed on round tensile tests and flat u notch tests
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15

von, Rosen Michael. "Modelling of bolt fracture." Thesis, Linköpings universitet, Hållfasthetslära, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-107892.

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Computer simulations are widely used in the truck industry in order to provide assistance in the product development. Bolt joints are common in trucks. A bolt fracture usually has a great influence on how a truck structure will behave in a crash. Therefore, when simulating truck crashes it is important to be able to predict when bolt fracture occurs. A material model for 10.9 bolts has been calibrated and validated by using the finite element software LS-DYNA. The material model consists of a failure strain surface, which depends on the triaxiality, Lode parameter and the element size. In this thesis, the calibrated material model is referred to as the bolt model. A good agreement to predict the force at fracture in bolts between simulation model results and physical test results has been obtained. Still, further validation is needed to evaluate the bolt model completely.
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16

Basaran, Merdan [Verfasser]. "Stress State Dependent Damage Modeling with a Focus on the Lode Angle Influence / Merdan Basaran." Aachen : Shaker, 2011. http://d-nb.info/1070151114/34.

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17

Wheeler, Candace A. "The Comstock cemeteries changing landscapes of death /." abstract and full text PDF (UNR users only), 2008. http://0-gateway.proquest.com.innopac.library.unr.edu/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:1456398.

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18

Smyth, D. "Biogeochemical prospecting applied to deposits of orthomagmatic copper-nickel-PGE, lode gold and lead in Ireland." Thesis, Queen's University Belfast, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.390857.

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19

Carvalho, Emerson de Resende. "A imiscibilidade de fluidos em mineralizações auriferas do tipo lode na Bacia Paleoproterozoica de Jacobina, BA." [s.n.], 2001. http://repositorio.unicamp.br/jspui/handle/REPOSIP/287696.

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Orientadores : Roberto Perez Xavier, João Batista Guimarães Teixeira
Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Geociencias
Made available in DSpace on 2018-07-28T09:47:40Z (GMT). No. of bitstreams: 1 Carvalho_EmersondeResende_M.pdf: 4408664 bytes, checksum: 09dbce1ff63054f25b6c32088acbf795 (MD5) Previous issue date: 2001
Resumo: A Bacia Paleoproterozóica de Jacobina contém metaconglomerados auríferos do tipo Witwatersrand que são economicamente importantes e, subordinadamente, mineralizaçães auríferas epigenéticas sub-econômicas, representadas por brechas hidráulicas e sistemas de veios de quartzo hospedados em metaconglomerados (domínio I) e no contato entre quartzito e rochas máficas/ultramáficas intrusivas (domínio 11). Estudos petrográfico, microtermométrico e por microespectrometria Raman de inclusões fluidas contidas em quartzo associado aos domínios I e 11 revelaram três tipos composicionais de inclusões primárias/pseudosecundárias: inclusões (AC) constituídas por H20-C02(:tCH4), de baixa salinidade (média de 2% em peso eq. NaCI) e com razão C02/H20 variável (O, 1~C02:::;;O,8); inclusões (C) ricas em C02(:tCH4) com Vco2~,8; e inclusões aquosas (A) de baixa salinidade, contendo pequenas quantidades de C02. As inclusões AC predominam no domínio I, enquanto as inclusões C prevalecem no domínio 11. O pequeno conteúdo em CH4 (:::;;4 mol%) está restrito ao domínio 11. Inclusões aquosas secundárias de salinidade variável interceptam todos os outros tipos de inclusões e são interpretadas como decorrentes de um regime de fluido ativo durante o soerguimento, posterior à formação da mineralização. Feições texturais fornecem fortes evidências da associação temporal e espacial das inclusões AC, C e A. Em ambos os domínios, a homogeneização da fase carbônica indicou uma variação na densidade do C02 de 0,47 a 0,98 g/cm3 para as inclusões AC e de 0,61 a 1,02 g/cm3 para as inclusões C. As inclusões AC com Xco2::;;33 mol% e 22::;;V::;;35 cm3/mol mostraram homogeneização total para a fase aquosa no intervalo de 215°C a 340°C, enquanto as inclusões AC com Xco2~34mol% e V~31cm3/mol homogeneizaram para a fase carbônica no intervalo de 210°C a 360°C. Os dados obtidos através da análise global de gases por espectrômetro de massa quadrupólo mostraram um nítido fracionamento de voláteis (CH4, N2, C02, H28 e 802) em direção à fase carbônica. Os dados obtidos a partir das inclusões fluidas, tais como: (a) a presença de assembléias de inclusões com XC02 variável, atribuído ao aprisionamento heterogêneo; (b) a existência de inclusões ricas em H20 e ricas em C02 contemporâneas em uma assembléia, interpretadas como os membros extremos de um fluido aquo-carbônico imiscível; (c) a homogeneização total tanto para a fase aquosa como para a fase carbônica no mesmo intervalo de temperatura: e (d) o fracionamento de voláteis para a fase vapor durante sua separação da solução, satisfazem os requerimentos da imiscibilidade. A adequação dos dados Xco2-TH à curva de solvus experimental assegura a ocorrência da separação de fases no sistema H20-NaCI-C02-(:tCH4). Conforme a análise global de voláteis, o comportamento da razão C02/CH4 sugere que o fluido aquo-carbônico homogêneo foi submetido a um estágio avançado de imiscibilidade. O alto grau de imiscibilidade provocou uma separação física quase completa entre as fases aquosa e carbônica e pode explicar o predomínio de inclusões ricas em C02 no domínio 11. A imiscibilidade de fluidos é um processo episódico produzido pela flutuação cíclica da pressão do fluido durante a ascensão da solução hidrotermal ao longo de descontinuidades estruturais e a formação da brecha e veios de quartzo. Com base nestas evidências, combinado com a natureza das litologias hospedeiras (e.g. quarto não reativo é o mineral dominante nos metaconglomerados e quartzitos), a imiscibilidade foi o principal mecanismo responsável pela deposição do ouro, que, neste contexto, ocorreu entre 200°C e 350°C e de 1,0 a 2,5 kbar
Abstract: The Paleoproterozoic Jacobina Basin is characterized by containing economically important Witwatersrand-type gold quartz-pebble metaconglomerates and, more subordinately, sub-economical epigenetic gold mineralizations represented by hydraulic breccia and quartz vein systems hosted by metaconglomerate (domain I) and at the contact between quartzite and intrusive maficlultramafic rocks (domain 11). Petrographic, microthermometric and laser Raman microspe ctroscopic studies of fluid inclusions in auriferous quartz associated with domains I and 11 revealed three compositional types of primary/pseudosecondary inclusions: (AC) H20-C02(:tCH4) inclusions of low salinity (mean of 2 wt % eq. NaCI) and variable C02/H20 volume ratios (0,1 ~Vco2~O,8); (C) C02(:f:CH4)-rich inclusions with Vco2~O,8; and (A) low salinity H20 inclusions containing small amounts of C02. The AC inclusions predominates in domain I while C inclusions prevails in domain 11. The low content in CH4 (~4 mol%) is restricted to domain 11. Secondary H20 inclusions of variable salinity transects ali the others types of inclusions and are interpreted as a fluid regime active during uplifi, afier the formation of the mineralization. Textural features provides strong evidence of temporal and spatial association of the AC, C and A inclusions. In both domains, the homogenization of the carbonic phase indicated a variation in the C02 density of 0,47 to 0,98 g/cm3 for AC inclusions and of 0,61 to 1,02 g/cm3 for C inclusions. The AC inclusions with Xco2::;;33 mol% and 22::;;V::;;35 cm3/mol showed total homogenization to the H20 phase in the range of 215°C to 340°C, whereas AC inclusions with Xco2~34mol% and V~31cm3/mol and C inclusions homogenized to the C02 phase in the range of 210°C to 360°C. Data obtained from bulk gas analysis in fluid -inclusions by quadrupole mass spectrometry showed a clear fractionation of the volatile phases (CH4, N2, C02, H25 and 502) towards the carbonic phase. Fluid inclusion constraints: (a) the presence of variable XC02 inclusions assemblages which was attributed to heterogeneous entrapment; (b) the existence of contemporaneous H20-rich and COrrich inclusions in an assemblage, interpreted as end-members of immiscible aqueous carbonic fluid; (c) total homogenization to the H20 and C02 phases in the same range of temperatures; and (d) fractionation of volatiles to vapor phase during its separation of the solution, satisfy the requirement of immiscibility. The conformation of Xcor T H data to experimental solvus curve assures the H20-NaCI-COr(:tCH4) system phase separation. According to bulk volatile analysis the C02/CH4 ratio trends suggests that the homogeneous aqueous carbonic fluid was submitted to an advanced stage of immiscibility. The high grade of immiscibility caused an almost entire separation of the H20 and C02 phases and can explain the prevalence of C02-rich inclusion in domain li. Fluid immiscibility is a episodic process produced by cyclic fluctuation of fluid pressure during ascension of hydrothermal solutions along structural discontinuities and hydraulic breccia and quartz vein formation. Based on these evidences, combined-with the nature of the host lithologies (e.g. non-reactive quartz is the dominant mineral in metaconglomerate and quartzites), the immiscibility was the principal mechanism responsible for gold deposition that, in this context, occurred between 200°C and 350°C and 1,0 to 2,5 kbar
Mestrado
Metalogenese
Mestre em Geociências
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Reinicke, Albrecht [Verfasser], Hartmut [Gutachter] Lode, Kai-Uwe [Gutachter] Eckardt, and Konrad [Gutachter] Reinhardt. "Akute Phase Reaktion nach kardiopulmonaler Reanimation / Albrecht Reinicke ; Gutachter: Hartmut Lode, Kai-Uwe Eckardt, Konrad Reinhardt." Berlin : Humboldt-Universität zu Berlin, 2004. http://d-nb.info/1207630152/34.

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Reid, Anthony. "The structural configuration and evolution of Lower lead lode and the 2 lens dropper, Broken Hill, NSW /." Title page, contents and summary only, 1999. http://web4.library.adelaide.edu.au/theses/09SB/09sbr353.pdf.

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22

Holman, Tamara J. "Social construction of technology in the workplace| Lode mining in the Fairbanks Mining District, Alaska 1902-1942." Thesis, University of Alaska Anchorage, 2016. http://pqdtopen.proquest.com/#viewpdf?dispub=10141261.

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This thesis examines the social construction of technological practice of the Fairbanks Mining District (1902–1942) in order to enrich an understanding of the relationships among miners, mining endeavors, and cultures of work. Framing the study are the two theoretical approaches: sociotechnical systems and chaînes opératoires. A regional analysis was conducted using archaeological data gathered as a part of a hazard mitigation study of abandoned mining lands. These data are combined with architectural reconstruction drawings, census data, geological reports, and archival materials to posit connections within the district, discern patterns, and examine how these changed over time. This study revealed that people’s relationships in the district were diverse and dynamic, going far beyond simple class hierarchies of labor or capital. A preference for California style milling practices and mill architecture are clear, despite detractors like the inappropriateness for an Alaska climate or the mill’s relative efficiency, indicating that preference ruled over efficiency.

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23

Driscoll, Alan J. "Lode gold deposit characterization using evidence from stream sediments: an example from Brush Creek, Montgomery County, Virginia." Thesis, Virginia Polytechnic Institute and State University, 1989. http://hdl.handle.net/10919/52083.

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Placer ore minerals are commonly intergrown with "relict" phases that coexisted with the ore mineral in the original lode deposit. Studying these relict phases can yield important information about the nature, and formation of the lode deposit. This type of study can be useful in areas with poor exposure, areas that are remote, or areas where discretion is important. Analysis of the heavy mineral suite of stream sediments from the Brush Creek area shows no correlation between the heavy minerals and the gold. However, analysis of the relict phases intergrown with the gold grains yields important results. Placer gold grains recovered from streams draining the Brush Creek deposit, in southwestern Virginia, contain relict quartz, orthoclase, ilmenite and mica. Textures, and fluid inclusion composition and character in the relict quartz, indicate that the gold mineralization post dated the mylonitization associated with the Fries ductile deformation zone, which hosts the gold mineralization. The relict orthoclase is interpreted to be adularia, which is common in low-temperature, hydrothermal environments. The intergrowth textures of the gold and ilmenite show that the ilmenite was present in the country rocks prior to gold mineralization, and was not, therefore, cogenetic with the gold. The relict mica was not positively identified, but is believed to be chlorite, which is consistent with the proposed low temperature mineralization. The textures of the relict phases indicate that gold mineralization occurs in late, brittle fractures, with little or no significant alteration. The study of the relict phases intergrown with the alluvial gold grains has yielded information that otherwise could only have been obtained by more advanced, but also much more expensive, exploration techniques.
Master of Science
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24

Mlynarczyk, Michal S. J. "Constraints on the genesis of lode-style tin mineralization : evidence from the San Rafael tin-copper deposit, Peru." Thesis, McGill University, 2005. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=85939.

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Fluid evolution at the Peruvian San Rafael deposit, which represents the world's largest hydrothermal tin lode was marked by two contrasting episodes. The early stage, characterized by intense sericitic and tourmaline alteration was barren and produced numerous tourmaline-quartz veins, which are sealed and reflect largely lithostatic conditions of formation. A subsequent reopening of the vein-breccia system initiated the ore stage, which was characterized by a distinctive chloritic alteration and an open fracture-filling vein style. The first part of the ore stage was dominated by tin deposition and resulted in the formation of abundant cassiterite-quartz-chlorite-bearing veins and breccias, at depth in the lode. This was followed by copper deposition (with subordinate tin), which concentrated sulfide ores in the upper part of the vein system. The waning stages of hydrothermal activity superimposed late, barren quartz veins on earlier mineralization.
The delta34S values of sulfide minerals from San Rafael range between +2 and +6 ‰, suggesting a large-scale hydrothermal system, supplied by a relatively homogenous, presumably magmatic source of sulfur. Stability relationships of the ore minerals indicate that the ore fluids were reducing, which is consistent with their capacity to transport significant quantities of tin.
Microthermometric studies of fluid inclusions in cassiterite, quartz, tourmaline and fluorite showed that the fluids responsible for the early, barren stage were hot, hypersaline magmatic brines (>340-535°C, 34-62 wt.% NaCl eq.), whereas the ore stage fluids had a moderate temperature and salinity (>230-360°C, 0-21 wt.% NaCl eq.). The local association of minor hematite with cassiterite, and the ubiquitous replacement of pyrrhotite by pyrite, marcasite and hematite, indicate that the ore fluids became progressively more oxidizing. In addition, the stable isotope compositions of tourmaline, cassiterite, wolframite, quartz, chlorite, calcite, and siderite reveal that the early fluid had a magmatic signature, but its delta18O value markedly decreased with time. These trends are consistent with mixing of the ore fluids with a cooler, dilute fluid, enriched in the light oxygen isotope, and cannot be explained by boiling or simple cooling. Fluid-rock interaction was not a control on tin deposition either, as chloritic alteration of granitic rocks increases the fluid acidity, and this in turn increases tin solubility.
I infer that the creation of several large fault jogs at depth in the lode, synchronous with hydrothermal activity at the San Rafael igneous center, focused an influx of heated meteoric waters, which mixed with tin- and iron-rich magmatic brines. The oxidation, dilution, cooling and acid neutralization of the ore fluids destabilized chloride complexes of tin and iron, and triggered the massive precipitation of cassiterite with chlorite, in localized, high-grade ore shoots, as opposed to a dissemination of tin in the chloritic alteration.
The formation of the San Rafael deposit took place in Late Oligocene, at the onset of a major metallogenic episode in the Inner Arc of the Central Andes. We propose that Tertiary tin-tungsten(-silver) mineralization in this province (and possibly some of the earlier metallogenic episodes) was produced by a recurrent compressional interaction between the Farallon/Nazca oceanic plate and the South American continent. Periodic "collisions" between the tectonic plates were focused on this segment of the Andean orogen and generated in its back arc voluminous peraluminous magmas, which evolved by fractional crystallization and exsolved the fluids responsible for the rich Sn-W(-Ag) mineralization.
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25

Hügel, Dario Frank [Verfasser], and Lode [Akademischer Betreuer] Pollet. "Self-consistent methods for interacting lattice bosons with U(1)-symmetry-breaking / Dario Frank Hügel ; Betreuer: Lode Pollet." München : Universitätsbibliothek der Ludwig-Maximilians-Universität, 2018. http://d-nb.info/1154683877/34.

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26

McKeagney, Catherine Judith. "Structural and alteration characteristics of the Indarama lode gold deposit, Zimbabwe : implications for craton-wide tectonism and mineralization." Thesis, University of Southampton, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.264744.

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27

Tola, Tola Adrian Patricio. "Analytical and Experimental Investigation of Low-Cycle Fatigue Fracture in Structural Steel." Diss., Virginia Tech, 2020. http://hdl.handle.net/10919/100051.

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The mechanism of metal material failure due to inelastic cyclic deformations is commonly described as Low-Cycle Fatigue (LCF). Fracture in steel structures caused by earthquakes can be associated with this mechanism. Mathematical expressions describing the material deterioration due to LCF are often referred to as LCF laws. The accurate determination of the safety of steel structures against earthquake-induced failure requires the use of LCF laws which have been sufficiently validated with experimental test data. The present study combined experimental testing and computational simulation to enhance the understanding of structural steel fracture due to LCF. The experiments were conducted in specimens extracted from the flat and corner regions of two rectangular steel hollow sections with different thickness. A total of 60 cylindrical specimens with a circumferential notch were subjected to different combinations of axial and torsional loading. The loading protocols and notch geometry were designed to produce different stress states at the location of fracture initiation. Finite element analyses were conducted to obtain the stress state and inelastic strains at the fracture initiation location. This information was then used for the calibration of five existing LCF laws. The calibration also allowed the comparative evaluation of the capability of the different laws to capture fracture initiation for different stress states, with a single set of values for the various parameters. The accuracy of the calibrated LCF laws to predict fracture initiation in a large-scale test was also investigated. To this end, a test was conducted on a rectangular steel tube subjected to cyclic axial loading. A finite element analysis of this test was conducted, and predictions of the instant and location of fracture initiation using the calibrated LCF laws were compared with the experimental observations.
Doctor of Philosophy
The mechanism of material failure due to repeated cycles of large deformations is denoted as Low-Cycle Fatigue (LCF); this failure mechanism can occur in steel structures subjected to loading conditions such as those induced by earthquakes. Mathematical expressions that evaluate the material deterioration due to LCF are often used to predict the instant and location of fracture initiation in small-scale and large-scale tests. An experimental program was conducted for the study of fracture associated with LCF. A total of 60 specimens were fabricated with material extracted from the flat and corner regions of two rectangular steel tubes; the applied loads elongated and/or twisted the specimens until they ruptured. Computational simulations of these tests were conducted to obtain key information at the location of the observed fracture initiation. This information was used to adjust five mathematical expressions suggested by previous researchers that could predict the same instant of fracture initiation observed in the experiments. The accuracy of the predictions from each of these mathematical expressions was evaluated. The accuracy of these mathematical expressions to predict fracture initiation in a large-scale test was also investigated. To this end, an experiment was conducted on a rectangular steel tube subjected to repeated cycles of deformation. A computational simulation of this test was also developed, and predictions of the instant and location of fracture initiation were compared with the experimental observations.
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28

Kroiß, Peter [Verfasser], and Lode [Akademischer Betreuer] Pollet. "Quantum Monte Carlo simulations of the Fermi-polaron problem and bosons with Gaussian interactions / Peter Kroiß ; Betreuer: Lode Pollet." München : Universitätsbibliothek der Ludwig-Maximilians-Universität, 2017. http://d-nb.info/1125883936/34.

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29

Greitemann, Jonas [Verfasser], and Lode [Akademischer Betreuer] Pollet. "Investigation of hidden multipolar spin order in frustrated magnets using interpretable machine learning techniques / Jonas Greitemann ; Betreuer: Lode Pollet." München : Universitätsbibliothek der Ludwig-Maximilians-Universität, 2019. http://d-nb.info/1199816655/34.

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30

Lima, Luiz Claudio. "Geologia do depósito LODE Au-As-Sb Laranjeiras, em metaturbitos do Grupo Nova Lima, Quadrilátero Ferrífero, Minas Gerais, Brasil." Universidade Federal de Minas Gerais, 2011. http://hdl.handle.net/1843/MPBB-8YXGJH.

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The Laranjeiras Gold Deposit (~1 Moz @6.32 g/t Au) is located at the eastern border of the Iron Quadrangle-QF, and is part of the Córrego do Sítio Lineament. It is hosted in intercalated Neo Archean, strongly foliated metasedimentary rocks, encompassing clastic and volcanoclastic units, which belong to the upper portion of the Nova Lima Group, Rio das Velhas Supergroup. Diamond drill core logs (>150,000 m) and geologic mapping in the open pit mines led to the definition of the deposits stratigraphy. The Nova Lima Group is represented in the area by the Córrego do Sítio Unit, informally subdivided into Upper, Intermediate and Lower. The rocks of the Upper and Lower portions are characterized by their essentially psammitic composition, with greywacke predominating and subordinated lenses of sericitic and/or carbonaceous metapelites, besides horizons of heterogeneous iron formations containing magnetite, carbonates and quartz. The Intermediate portion corresponds to the conduit of gold mineralization, where carbonaceous schists predominate. They contain heterogeneous shear zones, with thicknesses ranging from less than one meter to tens of meters. These obliquely host mineralized bands that form quartz-carbonate veins in regional-scale, tension gash zones and that marked the end of the gold mineralization. Hydrothermal alteration of rocks hosting quartz veins include intense leaching of the carbonaceous material, with carbonate, sericite and sulfides formation in the surrounding rocks. Laranjeiras shows lenticular oblate orebodies, arranged in narrow, en echelon quartz-carbonate veins, with 1-4-m thickness, 60-400 height and length of 60-1200 meters, respectively. The dip direction is ~S76°E to S49°E, dipping at 45°-75° to the SE and plunging at 30°-46° towards N39°E and N51°E, in opposition to other gold mineralized zones of the Nova Lima Group, QF, which in general display plunges to the east and southeast. The geometry of the orebodies is a result of polyphase structural evolution, with four phases of deformation. A mylonitic foliation developed in shear zones that are subparallel to the regional foliation (Sn) of the rocks hosting the mineralization. It displays a maximum of N29°E/68°SE.A cleavage of extensional, wide spaced crenulations, Sn+1, is developed during the event Dn+1, with a maximum at N16Eº/30ºNW. It is marked by carbonaceous matter accumulated on the cleavage planes, which allow for their easy identification. During the Dn+2 phase, folds developed and inverted the attitude and dip of both Sn and Sn+1 surfaces without changing the angle between the two. This phase did not imprint any cleavage or mineral lineation and, therefore, Sn+2 surfaces could not be measured. The Sn+3 surface is an axial plane of a wide-spaced crenulation cleavage at an attitude of N35ºW/79ºNE, accompanied by fracture cleavage and kink folds on a decimetric scale. Swarms of metabasic dikes, with differing stages of metasomatic alteration, obliquely cut across and are locally parallel to all Archean units. Petrographic and scanning electron microscopic (SEM) studies identified the following ore and gangue minerals associated with veins and their host rocks in decreasing order of abundance: pyrite (FeS2) , arsenopyrite (FeAsS), pyrrhotite (FeS), berthierite (FeSb2S4), chalcopyrite (CuFeS2), sphalerite (ZnFeS), ullmanite (NiSbS), gersdorffite (NiAsS), cubanite (CuFe2S3), tetrohedrite ((Cu,Fe)12Sb4S13), pentlandite ((Fe,Ni)9S8), hematite (Fe2O3), rutile (TiO2), minerals of the boulangerite group (Pb5Sb4S11), galena (PbS), stibnite (Sb2S3), cobaltite (CoAsS), cinnabar (HgS), electrum (Ag-Au) and gold (Au). These overall represent less than 1%. Multi-element geochemical analyses resulted in the establishment of a positive correlation between Au in veins and surrounding clastic metasedimentary and metavolcanic rocks, with the following elements, in descending order: Sb > As > Ag > Cd > Se >Hg > P> Te > W > F > Bi > In > Sr > Sc > Cl > Rb > Sn > Tl > Cu > Pb > Zn > B > Ge > Mn > Mo > Re. In metabasic dike rocks, Au has a positive correlation in with the following elements, in descending order: As > Sb > Ag > Cr > Cs > Tl > W > Zn > Ba > Hg > Li > Ni >Rb > Cd > F. The relatively high grades of Cr and Ni and the high La/Y ratios indicate that the original sediments at the Córrego do Sítio Lineament originated also from the erosion of mafic and ultramafic rocks. On the basis on the overall geological characteristics, such as highly deformed host rocks, abundant quartz-carbonate-sulfide veinlets, carbonate, sericite and sulfide hydrothermal alteration, plus the spatial association with large-scale compressional structures, the Laranjeiras Gold Deposit is classified as orogenic.
O Depósito Aurífero Laranjeiras (~1 Moz @6,32 g/t Au) localiza-se na borda leste do QF e integra o Lineamento Córrego do Sítio. Hospeda-se em intercalações de rochas metassedimentares clásticas e vulcanoclásticas fortemente foliadas, neoarqueanas, da porção superior do Grupo Nova Lima, Supergrupo Rio das Velhas.Descrições de testemunhos de sondagem diamantada (>150.000 m) e mapeamento geológico nos openpits permitiram o estabelecimento da estratigrafia do depósito.O Grupo Nova Lima é representado na área pela Unidade Córrego do Sítio, subdividida informalmente em Superior, Intermediária e Inferior. A porção intermediária corresponde a corredor de mineralização, onde predominam xistos carbonosos. Os mesmos contêm zonas heterogêneas de cisalhamento, de espessuras submétricas a decamétricas, e que hospedam obliquamente faixas mineralizadas expressas como grandes zonas de veios quartzo-carbonáticos, tipo tension gashes de escala regional, e que encerram o grosso da mineralização aurífera.As rochas das porções Superior e Inferior caracterizam-se por composição essencialmente psamítica, com predomínio de metagrauvacas e subordinadas lentes de metapelitos sericíticos e/ou carbonosos, além de formações ferríferas heterogêneas.Os tipos de alteração hidrotermal nas rochas que envolvem os veios de quartzo incluem intensa lixiviação da matéria carbonosa, carbonatação, sericitização e sulfetação nas encaixantes.Laranjeiras apresenta corpos de minério em forma lenticular oblata, dispostos como estreitos veios quartzo-carbonáticos en echelon, com largura de 1-4, altura de 60-400 e comprimento de 60-1200 metros, respectivamente. A direção de mergulho é ~S76oE a S49ºE, mergulhando 45º-75º para SE, com caimento do plunge de 30º-46º na direção entre N39ºE e N51ºE, em contraposição à outras mineralizações auríferas do Grupo Nova Lima, QF, que em geral apresentam plunge no sentido leste a sudeste.A geometria dos corpos de minério resulta de evolução estrutural polifásica, 04 fases de deformação. Uma foliação milonítica desenvolve-se em zonas de cisalhamento subparalelas à foliação regional (Sn) das rochas encaixantes da mineralização. Apresenta um máximo de N29oE/68ºSE.Uma clivagem de crenulação extensional e espaçada, Sn+1, é desenvolvida no evento Dn+1, com máximos em N16Eº/30ºNW; é marcada pela remobilização de matéria carbonosa nos planos de clivagem, o que permite sua pronta identificação. Durante a fase Dn+2, desenvolvem-se dobras que invertem a atitude e mergulho das superfícies Sn e Sn+1, sem alterar o ângulo entre estas. Tal evento de deformação não registrou clivagem ou lineação mineral e, portanto, não é possível a medição de superfícies Sn+2 relacionadas a esta fase.A superfície Sn+3 é o plano axial de uma clivagem de crenulação espaçada com atitudes N35ºW/79ºNE, acompanhada por clivagem de fratura e kink folds decimétricas.Enxames de diques metabásicos, em diferentes estágios de alteração metassomática, cruzam obliquamente todas as unidades arqueanas. Estudos petrográficos e de microscopia eletrônica de varredura (MEV) permitiram a identificação dos seguintes minerais-minério e de ganga associados aos veios e às suas encaixantes, em ordem decrescente de abundância: pirita (FeS2) , arsenopirita (FeAsS), pirrotita (FeS), berthierita (FeSb2S4),calcopirita (CuFeS2), esfalerita (ZnFeS), ullmanita (NiSbS), gersdorfita (NiAsS), cubanita (CuFe2S3), tetraedrita ((Cu,Fe)12Sb4S13), pentlandita ((Fe,Ni)9S8), hematita (Fe2O3), rutilo (TiO2), minerais do grupo da boulangerita (Pb5Sb4S11), galena (PbS), estibnita (Sb2S3), cobaltita (CoAsS), cinábrio (HgS), eletrum (Ag-Au) e ouro (Au), que representam, no todo, quantidades inferiores a 1%. Análises geoquímicas mulltielementares permitem estabelecer uma correlação positiva do Au, em veios e rochas encaixantes metassedimentares clásticas, metavulcanoclásticas, com os seguintes elementos, segundo uma ordem decrescente: Sb > As > Ag > Cd > Se >Hg > P> Te > W > F > Bi > In > Sr > Sc > Cl > Rb > Sn > Tl > Cu > Pb > Zn > B > Ge > Mn > Mo > Re. O Au tem correlação positiva nas rochas metabásicas com os seguintes elementos, segundo uma ordem decrescente: As > Sb > Ag > Cr > Cs > Tl > W > Zn > Ba > Hg > Li > Ni >Rb > Cd > F. Os elevados teores de Cr e Ni e a alta razão La/Y indicam que os sedimentos originais, que geraram o pacote de rochas metassedimentares do Lineamento Córrego do Sitio, devem ser derivados da erosão de rochas máficas e ultramáficas. Com base nas características geológicas, como rochas encaixantes fortemente deformadas, abundantes venulações de quartzo-carbonato-sulfeto, alteração hidrotermal a carbonato, sericita e sulfeto, além da associação espacial com estruturas compressionais de grande escala, o Depósito Aurífero Laranjeiras é classificado como orogênico.
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31

He, Jie. "Structural setting, geochemistry, and temporal relationships of the lode gold deposits in the Star Lake-McLennan Lake area, northern Saskatchewan." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk2/tape17/PQDD_0028/NQ30616.pdf.

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32

Henze, Carsten [Verfasser], Gerhard [Akademischer Betreuer] Seeland, Dieter [Akademischer Betreuer] Kirschke, and Ernst-Jürgen [Akademischer Betreuer] Lode. "Bedeutung der Milchleistungsmerkmale bei Wegfall der Milchquotenregelung in der Europäischen Union / Carsten Henze. Gutachter: Gerhard Seeland ; Dieter Kirschke ; Ernst-Jürgen Lode." Berlin : Humboldt Universität zu Berlin, Landwirtschaftlich-Gärtnerische Fakultät, 2004. http://d-nb.info/1015129889/34.

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33

Creus, Pieter Koenraad. "Geology and structural controls of lode-gold mineralisation around the Navachab Gold Mine in the Pan-African Damara Belt of Namibia." Thesis, Stellenbosch : Stellenbosch University, 2011. http://hdl.handle.net/10019.1/17845.

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Thesis (MSc)--Stellenbosch University, 2011.
ENGLISH ABSTRACT: Numerous quartz-vein hosted gold prospects in the Karibib district in central Namibia testify to the presence of a large hydrothermal system during Pan-African times in rocks of the Damara Belt and centred around the Navachab Gold Mine. This study presents the results of the regional and detailed mapping of the Navachab synform, a NE-SW trending, regional-scale structure hosting a number of these gold prospects, locally referred to as the “zoo prospects”, in the direct vicinity of the main Navachab Gold Mine. The zoo prospects are located in the marble-dominated, up to 800 m thick Karibib Formation, which forms the core of the Navachab synform. Regional mapping of the synform identified six main lithological units comprising massive and banded dolomitic and calcareous marbles, intraformational breccias and interlayered calc-silicate felses. Despite characteristic thickness variations, the six units can be correlated throughout the synform, allowing for a lithostratigraphic correlation of units in the otherwise monotonous marble sequence. All of the prospects are spatially closely associated with and adjacent to unit 5, an up to 100 m thick, competent dolomitic marble unit. This suggests a strong lithological control of the mineralisation. The first-order Navachab synform formed during the regional D2 phase of deformation. The strongly non-cylindrical, doubly-plunging fold shows open- to close interlimb angles and a pronounced NW vergence in the SW, but is tight- to isoclinal and upright in the NE. Higher fabric intensities and detachment folding are confined to the subvertical limbs of the synform in the north. Here, structures record a subhorizontal, NW-SE directed co-axial shortening strain interpreted to have developed in response to the geometric hardening and layer-normal shortening following the rotation of the fold limbs to subvertical attitudes during progressive D2 shortening. The mineralisation of the zoo prospects is located where D2 high-strain zones intersect unit 5. This suggests an additional structural control of the mineralisation. The detailed mapping of the zoo prospects identified five distinct quartz-vein sets. The geometry, orientation and progressive deformation of the vein sets indicate that veining occurred during the late stages of the D2 event and during NW-SE directed, subhorizontal shortening. Areas of increased veining and mineralisation occur preferentially in areas of strain incompatibilities, where the combined effects of D2 strains and prominent lithological contacts created zones of localized dilatancy. This includes most prominently dilational jog geometries developed between anastomosing D2 shear zones, where hydrothermal fluid flow has produced pervasive quartz-vein stockworks. This also includes areas of detachment folding, where deformation of the rheological stiffer dolomitic marbles and less competent calcareous marbles has led to detachment surfaces and, locally, dilatancy. Zones of increased permeability are also created where two or more vein sets intersect, which is particularly common within and adjacent to boudin interpartitions of competent dolomite units and along rheologically prominent contacts. The zoo prospects illustrate the interplay of (1) prominent rheological contrasts between adjacent lithologies, (2) the presence of high-strain zones, and (3) the geometry of host structures for the formation of auriferous quartz veins in the Karibib district.
AFRIKAANSE OPSOMMING: Talle goud vooruitsigte, wat kwarts-aar geherberg is, in die Karibib-distrik in Sentraal-Namibië getuig van die teenwoordigheid van 'n groot hidrotermale stelsel tydens die Pan-Afrika-tye in die rotse van die Damara-Belt en is gesentreer rondom die Navachab goudmyn. Hierdie studie stel die resultate van die streeks- en gedetailleerde kartering van die Navachab sinform, 'n NW-SO neiging, streeks-skaal struktuur wat ʼn aantal van hierdie goud prospekteerplek herberg, plaaslik bekend as die "zoo prospects", in die direkte omgewing van die hoof Navachab goudmyn. Die “zoo prospects” is geleë in die marmer-gedomineerde, tot 800 m dik Karibib formasie, wat deel vorm van die kern van die Navachab sinform. Streeks kartering van die sinform het ses belangrike litologiese eenhede geidentifiseer wat uit massiewe en gestreepte dolomitiese kalk marmer, intraformasie breksie en tussengelaagdheid kalksilikaat felses bestaan. Ten spyte van die kenmerkende dikte variasies, kan die ses eenhede gekorreleer word oor die hele sinform, wat toelaat vir 'n litostratigrafiese korrelasie van eenhede in die andersins eentonige marmer opeenvolging. Al die vooruitsigte is ruimtelik verbind met en aangrensend aan Eenheid 5, 'n tot 100 m dik, bevoegde dolomitiese marmer-eenheid. Dit dui op 'n sterk litologiese beheer van die mineralisasie. Die eerste-orde Navachab sinform het gevorm tydens die plaaslike D2 fase van deformasie. Die sterk nie-silindriese, dubbelduikende plooi wys oop- tot noue tussenflankhoeke en 'n uitgespreek NW-vergensie in die SW, maar is styf- tot isoclinaal en regop in die NO. Hoër maaksel sterkte en losmaking plooie is beperk tot die subvertikale flank van die sinform in die noorde. Hierdie strukture is 'n aanduiding van 'n subhorisontale, NW-SO gerigte ko-aksiale verkorting wat geïnterpreteer is as vervorming wat ontwikkel het in reaksie op die geometriese verharding en die laag-normaal verkorting as gevolg van die rotasie van die plooi flanke tot subvertikale houdings tydens die progressiewe D2 verkorting. Die mineralisasie van die “zoo prospects” is geleë waar D2 hoë-spanning sones Eenheid 5 sny. Dit dui op 'n addisionele strukturele beheer van die mineralisasie. Die gedetailleerde kartering van die “zoo prospects” het vyf verskillende kwarts-aar stelle geïdentifiseer. Die geometrie, argitektuur en progressiewe vervorming van die aar-stelle dui daarop dat aar-vorming plaasgevind het gedurende die laat stadium van die D2 gebeurtenis en tydens die NW-SO gerugte, subhorisontale verkorting. Gebiede van verhoogde aar-vorming en mineralisasie kom verkieslik voor in die gebiede van vervorming verskille, waar die gekombineerde effek van die D2 vervorming en prominente litologiese kontakte sones van gelokaliseerde dilatansie. Dit sluit die mees prominente uitsettings uitwyking geometrie wat ontwikkel tussen anastomoserend D2 skuifskeursones, waar hidrotermale vloeistof stroming deurdringende kwarts-aar stokwerke geproduseer. Dit sluit ook die gebiede van losmaking plooie, waar die vervorming van die reologiese stywer dolomitiese marmer en minder bevoegde kalk marmer losmaking oppervlaktes gelei het, en plaaslik, dilatansie. Sones van 'n verhoogde deurlaatbaarheid is ook geskep waar twee of meer aar stelle sny, wat is veral algemeen binne en aangrensende boudin tussendeelpartisies van bevoegde dolomiet-eenhede en langs reologiese prominente kontakte. Die “zoo prospects” illustreer die wisselwerking tussen (1) prominente reologiese kontraste tussen aangrensende litologie, (2) die teenwoordigheid van hoë-spanning sones, en (3) die geometrie van die geherbergte strukture vir die vorming van goudhoudende kwarts are in die Karibib-distrik.
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34

Ebert, Franziska [Verfasser], Holger [Gutachter] Lode, James F. [Gutachter] Beck, and Marie von [Gutachter] Lilienfeld-Toal. "Evaluierung des Lysin-Demethylase-Expressionsmusters in kindlicher akuter Leukämie / Franziska Ebert ; Gutachter: James F. Beck, Marie von Lilienfeld-Toal, Holger Lode." Jena : Friedrich-Schiller-Universität Jena, 2019. http://d-nb.info/1206272414/34.

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35

Otto-Knapp, Ralf [Verfasser], G. [Gutachter] Kunkel, H. [Gutachter] Lode, and R. [Gutachter] Loddenkemper. "Die Regulation antioxidativer Enzyme nach Ozonexposition am Kulturmodell der menschlichen Nasenschleimhaut / Ralf Otto-Knapp ; Gutachter: G. Kunkel, H. Lode, R. Loddenkemper." Berlin : Humboldt-Universität zu Berlin, 2001. http://d-nb.info/1207666394/34.

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36

Burbano, Sandoval Carolina Fernanda. "Modelos elasto-plásticos e sua influência no processo de dimensionamento de componentes mecânicos." reponame:Repositório Institucional da UnB, 2014. http://repositorio.unb.br/handle/10482/16021.

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Dissertação (mestrado)—Universidade de Brasília, Faculdade de Tecnologia, Departamento de Engenharia Mecânica, 2014.
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Neste trabalho serão analisados os critérios tradicionais de projeto, bem como, critérios mais recentes, com intuito de se verificar a influência dos mesmos no processo de dimensionamento de componentes mecânicos, como uma estrutura de proteção veicular do tipo Roll Over Protection Structure-ROPS. Como primeira parte do trabalho, será feita uma revisão bibliográfica dos critérios de projeto de von Mises, Tresca, Mohr- Coulomb e Bai & Wierzbichi, bem como, uma análise dos principais tipos de estrutura de proteção veicular do tipo ROPS, existentes no mercado. Em uma segunda etapa, serão então implementados numericamente os quatro modelos constitutivos destacados acima em um programa acadêmico de elementos finitos desenvolvido em linguagem FORTRAN 90, onde o método da decomposição do operador e a integração impicita de Euler serão aplicados. Posteriormente, será escolhido um protótipo de estrutura ROPS com o intuito de se estudar a influencia dos modelos constitutivos no dimensionamento da estrutura, a modelagem em CAD do componente é realizada em ferramenta comercial GID-11 onde são também geradas as malhas de elemento finitos e bem como a analise do pos-procesado de resultados. Como etapa final, serão analisados dados como a distribuição da tensão equivalente ao longo da estrutura, bem como, o nível deformação plástica equivalente e dados elasto-plásticos como o nível de triaxialidade e o ângulo de Lode normalizado. Possíveis mudanças de forma, dimensões físicas e mudanças de materiais estruturais serão também alvo de análise. _______________________________________________________________________________________ ABSTRACT
In this work, it is analyzed the traditional and advanced criteria of project, in order to check their influence on the process of design of mechanical components, such as, the roll over protection structure-ROPS. In the first part of the work, a bibliographic review of the project criteria of von Mises, Tresca, Mohr-Coulomb and Bai & Wierzbicki is done, as well as, on the main types of ROPS, developed in the market. In a second step, numerical algorithms are suggested for the constitutive models under study and implemented in an academic finite element framework developed in FORTRAN 90 language, where the operator split methodology and the backward Euler scheme are applied. Furthermore, a roll over protection structure is taken, in order to performing the numerical simulations and analyzing the influence of important elasto-plastic parameters on the mechanical behavior of materials and the design of the structure. The CAD modeling component is held in GID-11 commercial tool which are also generated finite element meshes as well as the analysis and the post-processed results. With a final step, the distribution data as of the equivalent stress along the structure will be analyzed as well the level of equivalent plastic strain and elastic-plastic parameters, such as the level of triaxiality and the normalized Lode angle. Possible changes in the form, physical dimensions and changes in structural materials are also being analyzed.
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37

Lode, Axel U. J. [Verfasser], and Lorenz S. [Akademischer Betreuer] Cederbaum. "Tunneling Dynamics in Open Ultracold Bosonic Systems : numerically exact dynamics, analytical models, control schemes / Axel U. J. Lode. Betreuer: Lorenz S. Cederbaum." Heidelberg : Universitätsbibliothek Heidelberg, 2013. http://d-nb.info/1061054845/34.

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38

McCuaig, Thompson Campbell. "The genesis and evolution of lode gold mineralization and mafic host lithologies in the late-Archean Norseman Terrane, Yilgarn Block, western Australia." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp04/nq24001.pdf.

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39

Assie, Kouadio Etienne [Verfasser]. "Lode gold mineralization in the paleoproterozoic (Birimian) volcano sedimentary sequence of Afema gold district, southeastern Côte d'Ivoire / submitted by Kouadio Etienne Assie." [Clausthal-Zellerfeld] : [Univ.-Bibliothek], 2008. http://d-nb.info/987953656/34.

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Seidel, Diana [Verfasser], Holger [Akademischer Betreuer] Lode, Andreas [Akademischer Betreuer] Radbruch, and Hans-Dieter [Akademischer Betreuer] Volk. "Mechanism and efficacy of a GD2-specific immunotherapy using NK cells / Diana Seidel. Gutachter: Andreas Radbruch ; Holger N. Lode ; Hans-Dieter Volk." Berlin : Lebenswissenschaftliche Fakultät, 2015. http://d-nb.info/1068255447/34.

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Sali, Cletus Timah [Verfasser], Angelika Akademischer Betreuer] Eggert, Bertram [Akademischer Betreuer] Opalka, and Hartmut [Akademischer Betreuer] [Lode. "Evaluation of Galectin-1 as a Target for Therapy in Neuroblastoma / Sali Cletus Timah. Gutachter: Bertram Opalka ; Hartmut Lode. Betreuer: Angelika Eggert." Duisburg, 2011. http://d-nb.info/1015267971/34.

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42

Walter, Elisabeth [Verfasser], Holger [Gutachter] Lode, James F. [Gutachter] Beck, and Meinolf [Gutachter] Suttorp. "Evaluierung des Histon-Lysin-Demethylasen-Isoenzym-Expressionsmusters in kindlicher akuter lymphoblastischer Leukämie / Elisabeth Walter ; Gutachter: James F. Beck, Meinolf Suttorp, Holger Lode." Jena : Friedrich-Schiller-Universität Jena, 2018. http://d-nb.info/1172206864/34.

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Seidel, Diana Verfasser], Holger [Akademischer Betreuer] [Lode, Andreas [Akademischer Betreuer] Radbruch, and Hans-Dieter [Akademischer Betreuer] Volk. "Mechanism and efficacy of a GD2-specific immunotherapy using NK cells / Diana Seidel. Gutachter: Andreas Radbruch ; Holger N. Lode ; Hans-Dieter Volk." Berlin : Lebenswissenschaftliche Fakultät, 2015. http://d-nb.info/1068255447/34.

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44

Schumer, Benjamin Nathan, and Benjamin Nathan Schumer. "Mineralogy of Copper Sulfides in Porphyry Copper and Related Deposits." Diss., The University of Arizona, 2017. http://hdl.handle.net/10150/626163.

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Porphyry copper deposits represent one of the largest copper reserves on Earth. They typically contain large, low-grade reserves of primary ore and higher-grade, supergene enrichment blankets of sulfide and oxide ores. Understanding the mineralogy of porphyry copper ores and ores related to porphyry copper systems is exceedingly important for several reasons, foremost of which are the information provided by ore mineral parageneses, assemblages, and mineral chemistry on evolution of these magmatic-hydrothermal systems, and information on mineral processing characteristics of the ores. The focus of this work is to better understand the mineralogy of supergene copper sulfides in porphyry copper systems and hypogene base metal lodes related to porphyry copper systems, and use this mineralogical knowledge to improve our understanding of the processes responsible for ore formation. The objectives of this study are accomplished by two means: focusing on the crystallography and crystal chemistry of minerals, and then applying this mineralogical knowledge to a supergene sulfide enrichment blanket and hypogene massive sulfides from base metal lodes in southeastern Arizona. The discovery of a new mineral, natropalermoite, NaSr2Al4(PO4)4(OH)4, provided the opportunity to use single-crystal X-ray diffraction to solve a crystal structure, and electron-probe microanalysis (EPMA) to study the crystal chemistry of natropalermoite and how the accommodation of Na in the structure changes lengthens the unit cell along [010] and shortens it along [100] and [001] compared to its lithium analogue, palermoite. Solution of the crystal structure of the mineral nickelskutterudite, (Ni,Co,Fe)As3, allowed for the investigation of anion deficiency in minerals of the skutterudite group, a problem whose solution has eluded researchers for nearly 100 years. Two skutterudite (CoAs3) and two nickelskutterudite samples were analyzed using single-crystal X-ray diffraction, EPMA, and procrystal electron density. The results showed fully-occupied anion sites and a cation surplus, which was accommodated in the icosahedral site, proving that minerals of the skutterudite group are not anion deficient. This mineralogical knowledge was applied to the supergene enrichment blanket in the Western Copper section of the Morenci mine, Greenlee County, and hypogene massive sulfide deposits associated with a porphyry copper deposit at Bisbee, Cochise County, Arizona. This is one of very few studies of supergene sulfide blankets ever completed. One drill hole through the supergene blanket at Western Copper was examined using ore microscopy and EPMA. Results showed dominant (Cu+Fe):S ratios of 1.80 ± 0.05, 1.92 ± 0.03, and 1.10 ± 0.10, with higher (Cu+Fe):S dominant high in the blanket and low ratios dominant near the base of the blanket. These values were interpreted to be controlled by activity of Cu2+, Fe2+, and Fe3+ in solution. Massive sulfide deposits at Bisbee were investigated using ore microscopy and EPMA in order to correct the previous conflicting reports of the mineralogy and paragenesis of this famous district and interpret constraints on conditions of ore-forming fluids. Results show four types of ore: chalcopyrite-rich with hematite and/or pyrite, bornite-rich, chalcocite-rich, and a Zn-Pb association. Chalcopyrite-rich ores formed first, followed by bornite-rich and chalcocite-rich ores. All ores were formed at relatively shallow depths from oxidized, moderately sulfur-rich fluids; early fluids were higher temperature and later fluids were lower temperature and considerably more sulfidized. Zinc-lead ores formed early and were continuously dissolved and reprecipitated distal to Cu-mineralization. These patterns are similar to many other base-metal lode districts worldwide, however Bisbee contains more Zn-Pb ore than other districts with hematite-containing ores and less than those without hematite.
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Zhang, Tingting. "Development of Plasticity and Ductile Fracture Models Involving Three Stress Invariants." University of Akron / OhioLINK, 2012. http://rave.ohiolink.edu/etdc/view?acc_num=akron1334113425.

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46

Alirezaei, Saeed. "Geochemical investigation of the lower crustal rocks in Bamble Shear Belt, southern Norway, implications for the source of gold in lode gold deposits." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape4/PQDD_0021/NQ57017.pdf.

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Stemler, James Uwe. "A fluid inclusion and stable isotopic examination of the Boston, greenstone belt hosted, Archean lode-gold deposit, Hope Bay volcanic belt, Nunavut, Canada." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape4/PQDD_0010/MQ59883.pdf.

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48

Belcher, Richard William. "Tectonostratigraphic evolution of the Swartland region and aspects of orogenic lode-gold mineralisation in the Pan-African Saldania Belt, Western Cape, South Africa." Thesis, Stellenbosch : Stellenbosch University, 2003. http://hdl.handle.net/10019.1/49789.

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Thesis (PhD)--Stellenbosch University, 2003.
ENGLISH ABSTRACT: The Swartland region in the western Cape, South Africa, covers approximately 5000 km2 and forms part of the Pan-African Saldania Belt that represents the southernmost extremity of the Pan-African orogenic belts in southern Africa. Regional mapping of the Swartland area shows that lithologies can be classified using predominantly structural and to a lesser extent lithological criteria. This led to the proposal of a new classification, were rocks of the previous classification of the Malmesbury Group are divided into two new groups, namely the Swartland and Malmesbury groups. The Swartland group can be divided into the Berg River and Moorreesburg formations, a series of quartz-chlorite-muscovite-feldspar schists, quartz schists, graphitic schists and limestones; and the Bridgetown formation, a series of metavolcanic rocks with WPB-MORB affinities that possibly represent seafloor. Deposition of the sediments is suggested to have occurred concurrently with deformation in an accretionary prism/fore-arc and was initiated with the opening of the lapetus Ocean at ca. 600 Ma. This early deformation event, Dt (ca. 575 Ma), only affected the Swartland group and exhibits pervasive bedding transposition, thrusting and imbrication of units creating a tectonostratigraphic sequence. Where identified, kinematic indicators and fold vergence indicate a top-to-the-west transport direction during the early, low-angle Di deformation. The Malmesbury group overlies the Swartland group, being locally separated by an unconformity. The Malmesbury group is a succession of conglomerates, grits and shales (Piketberg Formation), grading into greywackes, shales, siltstones, sandstones and minor limestones of the Tygerberg and Porterville formations. Sedimentation probably commenced after ca. 575 Ma and lasted until shortly after 560 Ma. Both the Swartland and Malmesbury groups were then deformed by the deformation event, D2 (ca. 552-545 Ma), and were intruded by the 552 to 510 Ma Cape Granite Suite. The Franschhoek Formation, formally part of the Malmesbury Group is now classified, along with the inferred ca. 535-510 Ma Magrug and Populierbos Formations of the previous Klipheuwel Group. The redefined Klipheuwel group documents a change in depositional environment from the continental slope/ocean trench, marine and flyschoid deposits of the Malmesbury group to continental, fluvial half-graben and graben deposits. Exhumation, extensive erosion and the formation of a peneplain, was followed by the deposition of the Table Mountain Sandstone Group around 550-510 Ma. The Spitskop gold prospect, located 10 km south of Piketberg, represents the first identified occurrence of mesothermal gold mineralisation in the Saldania Belt. Metamorphic devolatilisation of the Swartland group during Di led to the scavenging and transportation of gold along shallow-dipping shear zones that are contained within the early, sub-horizontal So/Si tectonic fabric. Pervasive fluid movement in the Spitskop area led to elevated gold values compared to background values throughout the lithologies at Spitskop. The lack of any economic-grade gold mineralisation is probably related to the absence of suitably orientated structures, such as high-angle faults, that are commonly believed to represent the prerequisite for large fluid throughputs that could result in economic-grade gold deposits. The mineralisation at Spitskop, however, provides a genetic model for further exploration of gold in the Swartland group.
AFRIKAANSE OPSOMMING: Die Swartland streek in die Wes-Kaap, Suid-Afrika, beslaan ongeveer 5000 km2 en vorm deel van die Pan-Afrikaanse Saldania-gordel wat die mees suidelike deel van die Pan-Afrikaanse orogene gordels in suidelike Afrika verteenwoordig. Regionale kartering van die Swartland streek dui aan dat die gesteentes geklassifiseer kan word deur oorwegend strukturele, en tot 'n mindere mate litologiese kriteria te gebruik. Gevolglik word ‘n nuwe klassifikasie voorgestel, waar gesteentes volgens die vorige klassifikasie van die Malmesbury groep verdeel word in twee groepe, naamlik die Swartland en Malmesbury groepe. Die Swartland groep kan verdeel word in die Bergrivier en Moorreesburg formasies, ‘n reeks kwarts-chloriet-muskoviet-veldspaat skis, kwarts skis, grafitiese skis en kalksteen; en die Bridgetown formasie, ‘n reeks metavulkaniese gesteentes met WPB-MORB affiniteite wat moontlik oseaanvloer verteenwoordig. Daar word voorgestel dat afsetting van die sedimente gelyktydig plaasgevind het saam met vervorming in ‘n akkresionere prisma/voorboog, geinisieer deur die opening van die lapetus Oseaan (ca. 600 Ma). Hierdie vroee vervorming, Di (ca. 575 Ma), het slegs die Swartland groep geaffekteer en vertoon deurdringende verplasing van gelaagdheid, oorskuiwing en imbrikasie van eenhede en het ‘n tektonostratigrafiese opeenvolging gevorm. Waar identifiseer, dui kinematiese aanwysers en plooi kanteling op ‘n bokant-na-wes beweging gedurende die vroee, lae hoek Di vervorming. Die Malmesbury groep oordek die Swartland groep, plaaslik geskei deur ‘n diskordansie. The Malmesbury groep bestaan uit ‘n opeenvolging konglomeraat, grintsteen en skalie (Piketberg formasie), wat gradeer in grouwak, skalie, sliksteen, sandsteen en ondergeskikte kalksteen van die Tygerberg en Porterville formasies. Sedimentasie het waarskynlik begin na ca. 575 Ma en het voortgeduur tot kort na 560 Ma. Beide die Swartland en Malmesbury groepe is hierna vervorm deur D2, (ca. 552-545 Ma) en daaropvolgend ingedring deur die 552 tot 510 Ma Kaap Graniet Suite. Die Franschhoek Formasie, voorheen deel van die Malmesbury Groep, word nou geklassifiseer tesame met die afgeleide ca. 535-510 Ma Magrug en Populierbos formasies as deel van die voorheen geklassifiseerde Klipheuwel groep. Die hergedefinieerde Klipheuwel groep dui op 'n verandering in afsettingsomgewing vanaf die kontinentale glooiing/oseaantrog, mariene en flyschoiede afsettings van die Malmesbury groep na kontinentale, fluviale half-graben en graben afsettings. Herblootstelling, omvattende erosie en die vorming van ‘n skiervlakte is gevolg deur die afsetting van die Tafelberg Sandsteen Groep random 520-510 Ma. Die Spitskop goudvoorkoms, 10 km suid van Piketberg, verteenwoordig die eerste identifiseerde voorkoms van mesotermale goudmineralisasie in die Saldania Gordel. Metamorfe ontvlugtiging van die Swartland groep gedurende Dt het aanleiding gegee tot die roofuitruiling en vervoer van goud langs laaghellende skuifskeursones in die vroee, subhorisontale S0/Si tektoniese maaksel. Deurdringende vloeistofbeweging in die Spitskop omgewing het aanleiding gegee tot verhoogde goudwaardes in vergelyking met agtergrond waardes dwarsdeur die litologiee by Spitskop. Die gebrek aan ekonomiese graad goud mineralisasie is waarskynlik verwant aan die afwesigheid van geskikte georienteerde strukture, soos hoe hoek verskuiwings, wat oor die algemeen beskou word as ‘n voorvereiste vir die toevoer van groot hoeveelhede vloeistof wat kon aanleiding gegee het tot ekonomiese graad goudafsettings. Die mineralisasie by Spitskop verskaf egter 'n model vir verdere goud eksplorasie in die Swartland groep.
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49

Zeng, Yan [Verfasser], H. [Gutachter] Lode, R. [Gutachter] Erttmann, and R. [Gutachter] Xiang. "T-cell mediated suppression of neuroblastoma following fractalkine gene therapy is amplified by targeted IL-2 / Yan Zeng ; Gutachter: H. Lode, R. Erttmann, R. Xiang." Berlin : Humboldt-Universität zu Berlin, 2006. http://d-nb.info/1208077031/34.

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50

Karolak, Cyprien. "CarboFrac : Analyse et modélisation de l'engrenage (d'un siège auto) en acier à faible teneur en carbone carbonitruré." Thesis, Paris Sciences et Lettres (ComUE), 2016. http://www.theses.fr/2016PSLEM057/document.

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Ce travail vise à améliorer la compréhension et la modélisation de la rupture des matériaux métalliques à gradient de propriétés. L'application se fait sur des pignons en acier 20MnB5 carbonitrurés insérés dans un "recliner", mécanisme de sécurité des siègesautomobiles. Le traitement de carbonitruration consisteà enrichir en carbone et azote une couche externe despièces en les chauffant dans le domaine austénitiquedans une atmosphère riche en ces deux éléments. Puisles pièces sont trempées afin de déclencher unetransformation martensitique. On obtient ainsi unmatériau à gradient de propriétés, intéressant pour despièces de transmission de puissance comme lesengrenages. Ce projet a commencé par l’analyse de larupture de mécanismes de sièges en test industriel. Celaa confirmé le double comportement à rupture binaire dumatériau : fragile sur une couche externe, ductile àl’intérieur. Un banc d’essai, spécialement conçu pour ceprojet, soumet une dent à un effort latéral jusqu’àrupture complète. Des observations in situ sonteffectuées et la courbe force-déplacement estenregistrée, montrant la diversité de comportement enfonction de la profondeur d'engagement des dents et dela présence ou non de la couche carbonitrurée. Desessais de traction, de flexion 4 points et de cisaillementsur éprouvettes papillons sont utilisés pour mesurer lespropriétés plastiques et calibrer les critères de rupturede la couche carbonitrurée comme de l'acier de base. Laplasticité de Von Mises avec une loi d'écrouissagesimple rend très bien compte de tous ces essaismécaniques. Différents critères de rupture ductile issusde la littérature sont calibrés; ils ne parviennent pas àreprésenter correctement tous les essais réalisés.Un critère plus adapté est donc proposé enconclusion de cette campagne expérimentale. Lasimulation de la rupture dans LS-Dyna est réaliséeavec une technique d'érosion d'éléments dont leslimitations sont discutées. La comparaison avec larupture de dent expérimentale permet d'évaluer lescritères numériques identifiés et d'analyser leslimites actuelles de la simulation, en particulier lanécessité de prendre en compte plus finement àl'avenir le gradient de propriétés mécaniques ainsique les contraintes résiduelles de compression dela couche carbonitrurée
This work aims at a better understanding and modeling of the failure of gradient metallic materials. It is applied to carbonitrided pinions made out of 20MnB5 steel, inserted in a "recliner", a safety mechanism of automotive seats. Carbonitriding induces high surface hardness while preserving significant core ductility. The experimental analysis of the fracture behavior of seat recliners in an industrial test confirmed the dual failure behavior of the component : brittle external layer, ductile core material. A test bench has been specifically designed for the project: one tooth is submitted to a lateral force until complete failure. In situ observations are performed and the load-displacement curve recorded, showing a variety of behaviors as a function of the teeth engagement depth and of the presence or not of the carbonitrided layer. Experimental tests with various tress states were conducted to measure plastic properties as well as to calibrate fracture criteria, for the carbonitrided layer and for the core steel. Von Mises plasticity and a simple strain hardening curve fit very well all these experiments. As fracture criteria from the literature were unable to predict failure correctly for all the mechanical tests, an adapted criterion has therefore been proposed as an outcome of this extensive mechanical testing campaign. Fracture simulation in LS Dyna has been performed using the element erosion technique, the limitations of which are discussed. Comparison with the experimental tooth fracture measurements allows evaluation of the proposed failure criteria, and enables to stress out and discuss the present limits of the simulation, concluding that it will be necessary in future work to account more finely for the mechanical property gradient together with the compressive residual stresses in the carbonitrided layer
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