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• 121. [Article] NANOARCHITECTURE-PROPERTY RELATIONSHIPS IN TISE2 BASED NANOLAMINATES FOR DEVELOPMENT OF NOVEL DESIGN STRATEGIES IN COMPOSITE THERMOELECTRIC MATERIALS

  This dissertation is centered on investigation of metastable thermoelectric thin film materials and is split into 3 primary sections. Section 1 focuses on formation mechanisms of FeSbx compounds from layered ...

  Citation × Citation Citation Abstract Copy Title: NANOARCHITECTURE-PROPERTY RELATIONSHIPS IN TISE2 BASED NANOLAMINATES FOR DEVELOPMENT OF NOVEL DESIGN STRATEGIES IN COMPOSITE THERMOELECTRIC MATERIALS Author: Bauers, Sage Year: 2017 This dissertation is centered on investigation of metastable thermoelectric thin film materials and is split into 3 primary sections. Section 1 focuses on formation mechanisms of FeSbx compounds from layered precursors. It was found that a compositionally favorable and homogeneous nucleation environment allowed for the nucleation of a metastable phase, which surprisingly resembles the local coordination environment of the precursors, even in cases where they are compositionally unfavorable. Over the course of this work, the technique of normal-incidence thin film pair distribution function analysis is introduced, which allows for rapid acquisition and analysis of local structure data from intact thin films. Section 2 investigates changes in the stacking sequences of ([PbSe]1+δ)m(TiSe2)n nanolaminate materials, which consist of interleaved layers of each compound in the chemical formula, and how these changes effect the thermoelectric power factor. Homologous series of systematically varying m and n values are investigated and measured properties are correlated back to the designed nanoarchitecture of the laminate materials. It is found that the compounds are stabilized by electron exchange between constituents at the interfaces, and that ‘doping’ of the laminate structure by changing the relative amounts of each constituent is an effective means of optimizing their transport properties. It is also shown that interface density between constituents can be utilized to optimize performance. Section 3 moves from the case of PbSe layers, which maintain their structure, to SnSe layers that significantly distort as the layer size is changed. The distortions in SnSe are observed to occur from templating off TiSe2 layers. As the size of the SnSe layers increases, relatively fewer templated interfacial atoms exist and stabilization of interior atoms must also be considered. The coarse behaviors developed in ([PbSe]1+δ)m(TiSe2)n hold, but the structural distortions in SnSe likely change the band structure of this constituent and hence the composite material, complicating the analysis. In some cases, these changes allow for radically different behavior, best exemplified with high TiSe2 ratios in ([SnSe]1+δ)1(TiSe2)n displaying significant enhancement of the Seebeck coefficient at cryogenic temperatures over the low-n and PbSe-containing analogues. This dissertation includes previously published and unpublished coauthored material. Title: NANOARCHITECTURE-PROPERTY RELATIONSHIPS IN TISE2 BASED NANOLAMINATES FOR DEVELOPMENT OF NOVEL DESIGN STRATEGIES IN COMPOSITE THERMOELECTRIC MATERIALS Author: Bauers, Sage Year: 2017 This dissertation is centered on investigation of metastable thermoelectric thin film materials and is split into 3 primary sections. Section 1 focuses on formation mechanisms of FeSbx compounds from layered precursors. It was found that a compositionally favorable and homogeneous nucleation environment allowed for the nucleation of a metastable phase, which surprisingly resembles the local coordination environment of the precursors, even in cases where they are compositionally unfavorable. Over the course of this work, the technique of normal-incidence thin film pair distribution function analysis is introduced, which allows for rapid acquisition and analysis of local structure data from intact thin films. Section 2 investigates changes in the stacking sequences of ([PbSe]1+δ)m(TiSe2)n nanolaminate materials, which consist of interleaved layers of each compound in the chemical formula, and how these changes effect the thermoelectric power factor. Homologous series of systematically varying m and n values are investigated and measured properties are correlated back to the designed nanoarchitecture of the laminate materials. It is found that the compounds are stabilized by electron exchange between constituents at the interfaces, and that ‘doping’ of the laminate structure by changing the relative amounts of each constituent is an effective means of optimizing their transport properties. It is also shown that interface density between constituents can be utilized to optimize performance. Section 3 moves from the case of PbSe layers, which maintain their structure, to SnSe layers that significantly distort as the layer size is changed. The distortions in SnSe are observed to occur from templating off TiSe2 layers. As the size of the SnSe layers increases, relatively fewer templated interfacial atoms exist and stabilization of interior atoms must also be considered. The coarse behaviors developed in ([PbSe]1+δ)m(TiSe2)n hold, but the structural distortions in SnSe likely change the band structure of this constituent and hence the composite material, complicating the analysis. In some cases, these changes allow for radically different behavior, best exemplified with high TiSe2 ratios in ([SnSe]1+δ)1(TiSe2)n displaying significant enhancement of the Seebeck coefficient at cryogenic temperatures over the low-n and PbSe-containing analogues. This dissertation includes previously published and unpublished coauthored material. Close

• 122. [Article] Climate and Ecological Change in Oligo-Miocene Mammals

  xiii, 198 p. : ill. (some col.)

  Citation × Citation Citation Abstract Copy Title: Climate and Ecological Change in Oligo-Miocene Mammals Author: Orcutt, John D. Year: 2012, 2011 xiii, 198 p. : ill. (some col.) Title: Climate and Ecological Change in Oligo-Miocene Mammals Author: Orcutt, John D. Year: 2012, 2011 xiii, 198 p. : ill. (some col.) Close

• 123. [Article] Mantle Heterogeneity and the Origins of Primitive Arc Lavas: An Experimental Study with a Focus on the Trans-Mexican Volcanic Belt

  Primitive, mantle-derived magmas provide important clues about the formation and equilibration conditions of magmas at depth. In subduction zones, it is uncommon for primitive magmas to ascend through ...

  Citation × Citation Citation Abstract Copy Title: Mantle Heterogeneity and the Origins of Primitive Arc Lavas: An Experimental Study with a Focus on the Trans-Mexican Volcanic Belt Author: Weaver, Stephanie Year: 2012, 2013 Primitive, mantle-derived magmas provide important clues about the formation and equilibration conditions of magmas at depth. In subduction zones, it is uncommon for primitive magmas to ascend through the shallow mantle and crust without undergoing chemical modification. Instead, magmas commonly differentiate through fractional crystallization, crustal assimilation, or magma mixing. Those rare primitive lavas that do erupt along a volcanic arc are useful for elucidating subduction-related processes within the mantle wedge (~30–80 km depth) and are the focus of this research. I used piston-cylinder apparatuses to investigate the high-pressure, high-temperature, H2O-undersaturated phase equilibria for several primitive compositions that have erupted at volcanic arcs. I aimed to reveal the permissible residual mantle mineralogy, as well as the P-T- H2O conditions over which the putative mantle melts last equilibrated before erupting. My work focuses on the Trans-Mexican Volcanic Belt (TMVB), where primitive compositions span a range of SiO2, total alkalies (K2O+Na2O), magmatic H2O, and incompatible trace element enrichments. Variations among these components are presumed to result from melting heterogeneous mantle that has been affected, to varying degrees, by a subduction component. Chapter III focuses on the phase equilibria of a Mexican basaltic andesite and an Aleutian basalt. Results show that hydrous basaltic andesite equilibrated with harzburgite in the shallow mantle, whereas the basalt equilibrated with lherzolite. The former appears more common in continental arcs and the latter in intraoceanic arcs. Chapter IV focuses on two alkaline lavas of varying K2O content from the TMVB that are transitional between potassic, hydrous minette and H2O-poor intraplate alkali basalt. Experimental phase relations and trace element modeling reveals that melting and/or mixing of peridotite and clinopyroxene-rich veins are likely involved in producing these transitional lava types. These experimental data are integrated with other petrologic and geophysical data to provide an along-arc perspective of mantle-melt equilibration in the TMVB. Primitive melts appear to commonly equilibrate with chemically heterogeneous mantle at depths above the "hot nose" of the mantle wedge. It is apparent that the shallow mantle wedge is a key component for understanding the geochemical complexities of subduction zone magmas. This dissertation includes previously published and unpublished co-authored material. Title: Mantle Heterogeneity and the Origins of Primitive Arc Lavas: An Experimental Study with a Focus on the Trans-Mexican Volcanic Belt Author: Weaver, Stephanie Year: 2012, 2013 Primitive, mantle-derived magmas provide important clues about the formation and equilibration conditions of magmas at depth. In subduction zones, it is uncommon for primitive magmas to ascend through the shallow mantle and crust without undergoing chemical modification. Instead, magmas commonly differentiate through fractional crystallization, crustal assimilation, or magma mixing. Those rare primitive lavas that do erupt along a volcanic arc are useful for elucidating subduction-related processes within the mantle wedge (~30–80 km depth) and are the focus of this research. I used piston-cylinder apparatuses to investigate the high-pressure, high-temperature, H2O-undersaturated phase equilibria for several primitive compositions that have erupted at volcanic arcs. I aimed to reveal the permissible residual mantle mineralogy, as well as the P-T- H2O conditions over which the putative mantle melts last equilibrated before erupting. My work focuses on the Trans-Mexican Volcanic Belt (TMVB), where primitive compositions span a range of SiO2, total alkalies (K2O+Na2O), magmatic H2O, and incompatible trace element enrichments. Variations among these components are presumed to result from melting heterogeneous mantle that has been affected, to varying degrees, by a subduction component. Chapter III focuses on the phase equilibria of a Mexican basaltic andesite and an Aleutian basalt. Results show that hydrous basaltic andesite equilibrated with harzburgite in the shallow mantle, whereas the basalt equilibrated with lherzolite. The former appears more common in continental arcs and the latter in intraoceanic arcs. Chapter IV focuses on two alkaline lavas of varying K2O content from the TMVB that are transitional between potassic, hydrous minette and H2O-poor intraplate alkali basalt. Experimental phase relations and trace element modeling reveals that melting and/or mixing of peridotite and clinopyroxene-rich veins are likely involved in producing these transitional lava types. These experimental data are integrated with other petrologic and geophysical data to provide an along-arc perspective of mantle-melt equilibration in the TMVB. Primitive melts appear to commonly equilibrate with chemically heterogeneous mantle at depths above the "hot nose" of the mantle wedge. It is apparent that the shallow mantle wedge is a key component for understanding the geochemical complexities of subduction zone magmas. This dissertation includes previously published and unpublished co-authored material. Close

• 124. [Article] The seismic structures of the U.S. Pacific Northwest and the scaling and recurrence patterns of slow slip events

  xv, 136 p. : ill. (some col.)

  Citation × Citation Citation Abstract Copy Title: The seismic structures of the U.S. Pacific Northwest and the scaling and recurrence patterns of slow slip events Author: Gao, Haiying Year: 2011, 2013 xv, 136 p. : ill. (some col.) Title: The seismic structures of the U.S. Pacific Northwest and the scaling and recurrence patterns of slow slip events Author: Gao, Haiying Year: 2011, 2013 xv, 136 p. : ill. (some col.) Close

• 125. [Article] Structural and electronic properties of hydrogenated nanocrystalline silicon employed in thin film photovoltaics

  xxi, 134 p. : ill. (some col.)

  Citation × Citation Citation Abstract Copy Title: Structural and electronic properties of hydrogenated nanocrystalline silicon employed in thin film photovoltaics Author: Hugger, Peter George, 1980- Year: 2011 xxi, 134 p. : ill. (some col.) Title: Structural and electronic properties of hydrogenated nanocrystalline silicon employed in thin film photovoltaics Author: Hugger, Peter George, 1980- Year: 2011 xxi, 134 p. : ill. (some col.) Close

• 126. [Article] Large-volume rhyolite genesis in caldera complexes of the Snake River Plain

  xix, 189 p. : ill. (some col.), maps (some col.)

  Citation × Citation Citation Abstract Copy Title: Large-volume rhyolite genesis in caldera complexes of the Snake River Plain Author: Watts, Kathryn Erin, 1983- Year: 2011 xix, 189 p. : ill. (some col.), maps (some col.) Title: Large-volume rhyolite genesis in caldera complexes of the Snake River Plain Author: Watts, Kathryn Erin, 1983- Year: 2011 xix, 189 p. : ill. (some col.), maps (some col.) Close

• 127. [Article] Main group supramolecular coordination chemistry: Design strategies and dynamic assemblies

  xxi, 172 p. : ill. (some col.) A print copy of this thesis is available through the UO Libraries. Search the library catalog for the location and call number.

  Citation × Citation Citation Abstract Copy Title: Main group supramolecular coordination chemistry: Design strategies and dynamic assemblies Author: Pitt, Melanie A., 1980- Year: 2010, 2009 xxi, 172 p. : ill. (some col.) A print copy of this thesis is available through the UO Libraries. Search the library catalog for the location and call number. Title: Main group supramolecular coordination chemistry: Design strategies and dynamic assemblies Author: Pitt, Melanie A., 1980- Year: 2010, 2009 xxi, 172 p. : ill. (some col.) A print copy of this thesis is available through the UO Libraries. Search the library catalog for the location and call number. Close

• 128. [Article] Identifying targets and function of the ubiquitin related modifier Urm1 in Saccharomyces cerevisiae

  xi, 81 p. : ill. A print copy of this thesis is available through the UO Libraries. Search the library catalog for the location and call number.

  Citation × Citation Citation Abstract Copy Title: Identifying targets and function of the ubiquitin related modifier Urm1 in Saccharomyces cerevisiae Author: Kubicek, Charles E., 1981- Year: 2010, 2009 xi, 81 p. : ill. A print copy of this thesis is available through the UO Libraries. Search the library catalog for the location and call number. Title: Identifying targets and function of the ubiquitin related modifier Urm1 in Saccharomyces cerevisiae Author: Kubicek, Charles E., 1981- Year: 2010, 2009 xi, 81 p. : ill. A print copy of this thesis is available through the UO Libraries. Search the library catalog for the location and call number. Close

• 129. [Article] Iron coordination chemistry of nitrogen,diazene,hydrazin,and ammonia : Investigating the mechanism of nitrogen reduction to ammonia

  xvi, 233 p. : ill. (some col.) A print copy of this thesis is available through the UO Libraries. Search the library catalog for the location and call number.

  Citation × Citation Citation Abstract Copy Title: Iron coordination chemistry of nitrogen,diazene,hydrazin,and ammonia : Investigating the mechanism of nitrogen reduction to ammonia Author: Crossland, Justin L., 1982- Year: 2010, 2009 xvi, 233 p. : ill. (some col.) A print copy of this thesis is available through the UO Libraries. Search the library catalog for the location and call number. Title: Iron coordination chemistry of nitrogen,diazene,hydrazin,and ammonia : Investigating the mechanism of nitrogen reduction to ammonia Author: Crossland, Justin L., 1982- Year: 2010, 2009 xvi, 233 p. : ill. (some col.) A print copy of this thesis is available through the UO Libraries. Search the library catalog for the location and call number. Close

• 130. [Article] The contribution of large, slow-moving landslides to landscape evolution

  xvi, 136 p. : ill. (some col.) A print copy of this thesis is available through the UO Libraries. Search the library catalog for the location and call number.

  Citation × Citation Citation Abstract Copy Title: The contribution of large, slow-moving landslides to landscape evolution Author: Mackey, Benjamin Hunter Year: 2010, 2009 xvi, 136 p. : ill. (some col.) A print copy of this thesis is available through the UO Libraries. Search the library catalog for the location and call number. Title: The contribution of large, slow-moving landslides to landscape evolution Author: Mackey, Benjamin Hunter Year: 2010, 2009 xvi, 136 p. : ill. (some col.) A print copy of this thesis is available through the UO Libraries. Search the library catalog for the location and call number. Close