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Wǝ́xa Sxwuqwálustn : pulling together identity, community, and cohesion in the Cowlitz Indian tribeWheeler, Leah January 2017 (has links)
In the last 30 years many changes have taken place within the Cowlitz Indian Tribe. These changes involve the tribe’s sovereignty and have greatly impacted the emic identity of the tribe. Previous identity research with the Cowlitz predates these changes and no longer accurately describe the Cowlitz. The question for this research was how have these changes affected the emic identity of the Cowlitz today as seen in their community and interactions? And how does their identity now compare with their identity in the times of pre-contact and initial contact with whites? This research uses Manuel DeLanda’s assemblage theory to assess and compare the emic identity of the contemporary and historical tribe in terms of sovereignty, identity, and cultural rejuvenation. When the structure, relationships, activities, and purposes of the tribe and groups within the contemporary tribe were analyzed, there was a striking resemblance to the community system described in early settler journals and histories of the Cowlitz. The research was cross-sectional, including ethnographic study, interviews of tribal members, document analysis, and historical analysis. In an attempt to allow the Cowlitz people to speak for themselves rather than project ideas onto the tribe, each section of the research first allows tribal members to voice their opinions and then relies on Cowlitz voices to confirm the analysis. The final dissertation was then submitted to the tribe for comment.
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Design of Ultra-Compact and Low-Power sub-10 Nanometer Logic Circuits with Schottky Barrier Contacts and Gate Work-Function EngineeringCanan, Talha Furkan 23 May 2022 (has links)
No description available.
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Structure and morphology of ultrathin iron and iron oxide films on Ag(001)Bruns, Daniel 21 November 2012 (has links)
This work investigates the initial growth of iron and iron oxides on Ag(001).
Surface structure and morphology of both post deposition annealed Fe films (in UHV and
O2 atmosphere) as well as reactive grown iron oxide films will be analyzed in detail by low energy electron diffraction (LEED) and scanning tunneling microscopy (STM). The stoichiometry at the surface of the iron oxide films will be determined by X-ray photoelectron spectroscopy (XPS) and Auger electron spectroscopy (AES). The main focus of this work is to shed light on the question whether the growth of iron oxide films on Ag(001) is accompanied by the formation of strain reducing dislocation
networks, or superstructures as found for other metal substrates in former studies. Here, we will distinguish between Fe films which were post deposition annealed in
a thin O2 atmosphere and reactively grown iron oxide films.
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Structural and magnetic properties of ultrathin Fe3O4 films: cation- and lattice-site-selective studies by synchrotron radiation-based techniquesPohlmann, Tobias 19 August 2021 (has links)
This work investigates the growth dynamic of the reactive molecular beam epitaxy of Fe3O4 films, and its impact on the cation distribution as well as on the magnetic and structural properties at the surface and the interfaces. In order to study the structure and composition of Fe3O4 films during growth, time-resolved high-energy x-ray diffraction (tr-HEXRD) and time-resolved hard x-ray photoelectron spectroscopy (tr-HAXPES) measurements are used to monitor the deposition process of Fe3O4 ultrathin films on SrTiO3(001), MgO(001) and NiO/MgO(001). For Fe3O4\SrTiO3(001) is found that the film first grows in a disordered island structure, between thicknesses of 1.5nm to 3nm in FeO islands and finally in the inverse spinel structure of Fe3O4, displaying (111) nanofacets on the surface. The films on MgO(001) and NiO/MgO(001) show a similar result, with the exception that the films are not disordered in the early growth stage, but form islands which immediately exhibit a crystalline FeO phase up to a thickness of 1nm. After that, the films grown in the inverse spinel structure on both MgO(001) and NiO/MgO(001). Additionally, the tr-HAXPES measurements of Fe3O4/SrTiO3(001) demonstrate that the FeO phase is only stable during the deposition process, but turns into a Fe3O4 phase when the deposition is interrupted. This suggests that this FeO layer is a strictly dynamic property of the growth process, and might not be retained in the as-grown films. In order to characterize the as-grown films, a technique is introduced to extract the cation depth distribution of Fe3O4 films from magnetooptical depth profiles obtained by fitting x-ray resonant magnetic reflectivity (XRMR) curves. To this end, x-ray absorption (XAS) and x-ray magnetic circular dichroism (XMCD) spectra are recorded as well as XRMR curves to obtain magnetooptical depth profiles. To attribute these magnetooptical depth profiles to the depth distribution of the cations, multiplet calculations are fitted to the XMCD data. From these calculations, the cation contributions at the three resonant energies of the XMCD spectrum can be evaluated. Recording XRMR curves at those energies allows to resolve the magnetooptical depth profiles of the three iron cation species in Fe3O4. This technique is used to resolve the cation stoichiometry at the surface of Fe3O4/MgO(001) films and at the interfaces of Fe3O4/MgO(001) and Fe3O4/NiO. The first unit cell of the Fe3O4(001) surface shows an excess of Fe3+ cations, likely related to a subsurface cation-vacancy reconstruction of the Fe3O4(001) surface, but the magnetic order of the different cation species appears to be not disturbed in this reconstructed layer. Beyond this layer, the magnetic order of all three iron cation species in Fe3O4/MgO(001) is stable for the entire film with no interlayer or magnetic dead layer at the interface. For Fe3O4/NiO films, we unexpectedly observe a magnetooptical absorption at the Ni L3 edge in the NiO film corresponding to a ferromagnetic order throughout the entire NiO film, which is antiferromagnetic in the bulk. Additionally, the magnetooptical profiles indicate a single intermixed layer containing both Fe2+ and Ni2+ cations.
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