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Die tribologischen Eigenschaften von vergoldeten elektrischen Kontakten

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ISBN: 9783731501466 Year: Pages: XIV, 138 p. DOI: 10.5445/KSP/1000037554 Language: GERMAN
Publisher: KIT Scientific Publishing
Subject: Technology (General)
Added to DOAB on : 2019-07-30 20:02:02
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Electrical contacts in automotive applications are exposed to thermal and vibration induced relative motion in the tribological contact. Fretting tests with an AuCo/Ni vs. Au/NiP ball to plate contact were conducted in order to describe the ongoing wear mechanisms. Furthermore, a global wear approach was chosen to quantify the overall wear. According to a predefined electrical failure criterion the connector lifetime is demonstrated in a model depending on oscillating amplitude, gold thickness and contact roughness. The electrical failure of the contact can be reduced to the wear of the gold platings leading to exposure of the nickel interlayer and consequently oxidation. Through material transfer, plowing, particle generation and the particle transport mechanisms the contact resistance increases and therefore limits the connector lifetime. The link between the lifetime models and the global wear approach allows for calculation of the lifetime when only the wear and the stress of the tribosystem are known.

Black Gold: Aboriginal People on the Goldfields of Victoria, 1850-1870

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ISBN: 9781921862953 Year: DOI: 10.26530/OAPEN_459855 Language: English
Publisher: ANU Press
Subject: Sociology --- History
Added to DOAB on : 2014-01-13 12:33:49
License: ANU Press

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Fred Cahir tells the story about the magnitude of Aboriginal involvement on the Victorian goldfields in the middle of the nineteenth century. The first history of Aboriginal–white interaction on the Victorian goldfields, Black Gold offers new insights on one of the great epochs in Australian and world history—the gold story.&#xD;&#xD;In vivid detail it describes how Aboriginal people often figured significantly in the search for gold and documents the devastating social impact of gold mining on Victorian Aboriginal communities. It reveals the complexity of their involvement from passive presence, to active discovery, to shunning the goldfields.&#xD;&#xD;This detailed examination of Aboriginal people on the goldfields of Victoria provides striking evidence which demonstrates that Aboriginal people participated in gold mining and interacted with non-Aboriginal people in a range of hitherto neglected ways.&#xD;&#xD;Running through this book are themes of Aboriginal empowerment, identity, integration, resistance, social disruption and communication.

Untersuchungen zur Herstellung geträgerter mono- und bimetallischer Nanopartikel mithilfe von überkritischem CO2

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ISBN: 9783731504665 Year: Pages: X, 201 p. DOI: 10.5445/KSP/1000051502 Language: GERMAN
Publisher: KIT Scientific Publishing
Subject: Chemical Engineering
Added to DOAB on : 2019-07-30 20:01:59
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Mono- and bimetallic nanoparticles were deposited onto different powdered supports by Supercritical Fluid Reactive Deposition (SFRD). Carbon dioxide was used as supercritical solvent and hydrogen as reduction agent. In order to optimize the production process unknown factors influencing the particle and product properties were extensively studied.

Black, White and Gold. Goldmining in Papua New Guinea 1878–1930

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ISBN: 9781921934339 Year: DOI: 10.26530/OAPEN_616883 Language: English
Publisher: ANU Press
Subject: History --- Migration --- Medicine (General)
Added to DOAB on : 2016-09-22 11:01:16
License: ANU Press

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Australian goldminers were among the first white men to have sustained contact with Papua New Guineans. Some Papua New Guineans welcomed them, worked for them, traded with them and learnt their skills and soon were mining on their own account. Others met them with hostility, either by direct confrontation or by stealthy ambush. Many of the indigenous people and some miners were killed. The miners were dependent on the local people for labourers, guides, producers of food and women. Some women lived willingly in the miners’ camps, a few were legally married, and some were raped. Working conditions for Papua New Guineans on the claims were mixed; some being well treated by the miners, others being poorly housed and fed, ill-treated, and subject to devastating epidemics. Conditions were rough, not only for them but for the diggers too. This book, republished in its original format, shows the differences in the experience of various Papua New Guinean communities which encountered the miners and tries to explain these differences. It is a graphic description of what happens when people from vastly different cultures meet. The author has drawn on documentary sources and interviews with the local people to produce, for the first time, a lively history.

Die Goldbüste des Septimius Severus: Gold- und Silberbüsten römischer Kaiser

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ISBN: 9783952454268 Year: Volume: 1 Pages: 208 DOI: 10.19218/3952454268 Language: German
Publisher: LIBRUM Publishers & Editors LLC
Subject: Archaeology --- History --- Mining and Metallurgy
Added to DOAB on : 2017-09-15 08:59:01
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Die Goldbüste des Kaisers Septimius Severus (193–211 n. Chr.) wurde im Jahr 1965 in Didymoteicho, dem antiken Plotinopolis (Nordgriechenland) gefunden. Dieser überaus seltene Fund hochstehender Goldschmiedearbeit liegt erstmals ausführlich untersucht und bebildert vor. Es handelt sich um die eine von nur zwei erhaltenen größeren Goldbüsten römischer Kaiser; das zweite, leicht unterlebensgroße Exemplar ist die Büste von Marc Aurel aus Avenches (Schweiz). Die 28 cm hohe Goldbüste des Septimius Severus wiegt knapp drei römische Pfund (980 g) und entspricht somit einem vielfach für solche Objekte verwendeten Gewichtsmodul. Goldporträts waren dem Kaiser vorbehalten. Als portable Bildnisse konnten sie den Kaiser bei offiziellen Handlungen wie am Gericht vertreten, sie dienten aber auch im Kaiserkult sowie in der römischen Armee, wo sie an der Spitze von Standarten mitgetragen wurden.Mit Beiträgen von Alessandra Giumlia-MairFotos der Goldbüste des Septimius Severus von Thanos Kartsoglou

Geomicrobiology and Biogeochemistry of Precious Metals

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ISBN: 9783038973461 9783038973478 Year: Pages: 182 DOI: 10.3390/books978-3-03897-347-8 Language: English
Publisher: MDPI - Multidisciplinary Digital Publishing Institute
Subject: Biotechnology --- Ecology --- Geology --- Earth Sciences --- Environmental Sciences
Added to DOAB on : 2018-11-20 10:57:53
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Precious metals continue to have economic and sociocultural importance, as their usage evolves and diversifies over time. Today, the industrial application of precious metals is increasing with the development of scientific and technological innovations. Especially, the biological cycling of these metals is receiving more and more attention, as the microbiota may be key to a range of issues regarding exploration, ore-processing and metallurgy, and the processing of electron waste. In this volume, we focus on enhancing the fundamental understanding of the biological processes that drive noble metal cycling and examine how this knowledge may be turned into biotechnolical applications.

Don't Weep a Gold Chain

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Book Series: Slavistische Beitraege ISBN: 9783876908724 Year: Pages: 309 Language: German
Publisher: Peter Lang International Academic Publishing Group
Subject: Linguistics
Added to DOAB on : 2019-01-15 13:31:33
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In this work I have endeavoured to apply the theory of primary and secondary systems as defined by D.S. Likhachev to Russian literary texts. Likhachev's idea amounts to the fact that those systems reoccur alternately. Thus, a primary system evolves into a so-called elliptic stage which enables a succeeding, secondary system to develop itself. Conversely, when the latter has become the standard norm it gradually evolves, in turn, into a similar elliptic stage. This, in turn, gradually develops into a primary system too. As far as the fluent succession of systems is concerned, Likhachev's theory differs from a similar theory developed by E.R. Curtius. The latter assumes that literary works should be divided into works with a Classicistic and a Manneristic character. The first develop into the latter which show a frozen character with no original qualities. In the end works with a new Classicistic character develop themselves. These, in turn, have a vital character again. In other words, in Curtius' scheme there is no place for a fluent alternation of systems the way there is in Likhachev's.

Mineralogy of Quartz and Silica Minerals

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ISBN: 9783038973485 9783038973492 Year: Pages: 274 DOI: 10.3390/books978-3-03897-349-2 Language: English
Publisher: MDPI - Multidisciplinary Digital Publishing Institute
Subject: Chemistry (General) --- Geology --- Earth Sciences --- Environmental Sciences
Added to DOAB on : 2018-11-20 11:34:22
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The present book reports recent contributions from research in the field of quartz and other silica minerals. The various forms of silica (SiO2) represent important constituents of the Earth crust and play a central role in the composition of geological materials. In particular, quartz is widely used as a raw material in numerous industrial sectors. The knowledge of the formation and specific properties of SiO2 rocks and minerals is indispensable for the understanding and reconstruction of geological processes, as well as for specific technical applications.The works presented in this book are contributed by leading scientists and deal with aspects of the formation and processing of SiO2 raw materials, the analysis of high-purity quartz, and the specifics and varieties (e.g., quartz, amethyst, opal, agate) of SiO2 modifications. The presentations cover the main interrelations between theoretical, analytical, and industrial studies and provide information concerning recent developments in the research on SiO2 materials.

Multi-Walled Carbon Nanotubes

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ISBN: 9783039212293 / 9783039212309 Year: Pages: 184 DOI: 10.3390/books978-3-03921-230-9 Language: eng
Publisher: MDPI - Multidisciplinary Digital Publishing Institute
Subject: Technology (General) --- Chemical Engineering
Added to DOAB on : 2019-08-28 11:21:27
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Since their discovery, multi-walled carbon nanotubes (MWCNTs) have received tremendous attention due to their unique electrical, optical, physical, chemical, and mechanical properties. Remarkable advances have been made in the synthesis, purification, structural characterization, functionalization, and application of MWCNTs. Their particular characteristics make them well suited for a plethora of applications in a number of fields, namely nanoelectronics, nanofluids, energy management, (electro)catalysis, materials science, construction of (bio)sensors based on different detection schemes, multifunctional nanoprobes for biomedical imaging, and sorbents for sample preparation or removal of contaminants from wastewater. They are also useful as anti-bacterial agents, drug delivery nanocarriers, etc. The current relevant application areas are countless. This Special Issue presents original research and review articles that address advances, trends, challenges, and future perspectives regarding synthetic routes, structural features, properties, behaviors, and industrial or scientific applications of MWCNTs in established and emerging areas.

Keywords

water based nanofluid --- carbon-nanotubes --- boundary layer --- heat generation --- thermal radiation --- curved stretching sheet --- numerical solution --- Single-Walled Carbon Nanotube (SWCNT) --- Multi-Walled Carbon Nanotube (MWCNT) --- MHD --- Casson model --- stretching sheet --- non-linear thermal radiation --- HAM --- zeolitic imidazolate framework --- multi-walled carbon nanotubes --- magnetic solid phase extraction --- organochlorine pesticides --- agricultural irrigation water --- Pd-CNT nanohybrids --- functionalized CNTs --- polarity --- semi-homogeneous catalysis --- heck reaction --- nanomaterials --- multi-walled carbon nanotubes --- synthesis methods --- electrochemical properties --- electrochemical sensors --- electroanalysis --- sensing applications --- multiwalled carbon nanotubes --- gold(I) --- gold(III) --- adsorption --- elution --- gold nanoparticles --- adsorption --- multi-walled carbon nanotubes --- nonylphenol --- kinetics --- multi-walled carbon nanotubes --- graphene oxide --- cerium oxide --- lubricating oil additives --- multi-wall carbon nanotube (MWCNT) --- azide-alkyne click chemistry --- RAFT polymerization --- PMMA --- carbon nanotubes --- composites --- radar absorbing materials --- complex permittivity --- chloride diffusion --- cement mortars --- carbon nanotubes --- mechanical properties --- electrical properties --- hydrophobic drugs --- drug delivery --- functionalized carbon nanotubes --- dissolution rate --- nanomedicine --- polymeric composites --- silicone rubber --- Ionic liquid --- carbon materials --- structural --- EMI shielding --- n/a

Mineral Surface Reactions at the Nanoscale

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ISBN: 9783038978961 / 9783038978978 Year: Pages: 220 DOI: 10.3390/books978-3-03897-897-8 Language: eng
Publisher: MDPI - Multidisciplinary Digital Publishing Institute
Subject: Science (General) --- Geology --- Earth Sciences
Added to DOAB on : 2019-06-26 08:44:06
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Reactions at mineral surfaces are central to all geochemical processes. As minerals comprise the rocks of the Earth, the processes occurring at the mineral–aqueous fluid interface control the evolution of the rocks and hence the structure of the crust of the Earth during processes such as metamorphism, metasomatism, and weathering. In recent years focus has been concentrated on mineral surface reactions made possible through the development of advanced analytical methods such as atomic force microscopy (AFM), advanced electron microscopies (SEM and TEM), phase shift interferometry, confocal Raman spectroscopy, and advanced synchrotron-based applications, to enable mineral surfaces to be imaged and analyzed at the nanoscale. Experiments are increasingly complemented by molecular simulations to confirm or predict the results of these studies. This has enabled new and exciting possibilities to elucidate the mechanisms that govern mineral–fluid reactions. In this Special Issue, “Mineral Surface Reactions at the Nanoscale”, we present 12 contributions that highlight the role and importance of mineral surfaces in varying fields of research.

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