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• 141. [Article] Emergent thermodynamics in a system of macroscopic, chaotic surface waves

  The properties of conventional materials are inextricably linked with their molecular composition; to make water flow like wine would require changing its molecular identity. To circumvent this restriction, ...

  Citation × Citation Citation Abstract Copy Title: Emergent thermodynamics in a system of macroscopic, chaotic surface waves Author: Welch, Kyle Year: 2016 The properties of conventional materials are inextricably linked with their molecular composition; to make water flow like wine would require changing its molecular identity. To circumvent this restriction, I have contstructed and characterized a two-dimensional metafluid, so-called because its constitutive dynamics are derived not from atoms and molecules but from macroscopic, chaotic surface waves excited on a vertically agitated fluid. Unlike in conventional fluids, the viscosity and temperature of this metafluid are independantly tunable. Despite this unconventional property, our system is surprisingly consistent with equilibrium thermodynamics, despite being constructed from macroscopic, non-equilibrium elements. As a programmable material, our metafluid represents a new platform on which to study complex phenomena such as self-assembly and pattern formation. We demonstrate one such application in our study of short-chain polymer analogs embedded in our system. Title: Emergent thermodynamics in a system of macroscopic, chaotic surface waves Author: Welch, Kyle Year: 2016 The properties of conventional materials are inextricably linked with their molecular composition; to make water flow like wine would require changing its molecular identity. To circumvent this restriction, I have contstructed and characterized a two-dimensional metafluid, so-called because its constitutive dynamics are derived not from atoms and molecules but from macroscopic, chaotic surface waves excited on a vertically agitated fluid. Unlike in conventional fluids, the viscosity and temperature of this metafluid are independantly tunable. Despite this unconventional property, our system is surprisingly consistent with equilibrium thermodynamics, despite being constructed from macroscopic, non-equilibrium elements. As a programmable material, our metafluid represents a new platform on which to study complex phenomena such as self-assembly and pattern formation. We demonstrate one such application in our study of short-chain polymer analogs embedded in our system. Close

• 142. [Article] The Performance of Four Native Perennial Forb Species Along a Climate Gradient in Pacific Northwest Prairies

  To determine how Pacific Northwest prairies are influenced by local site factors versus. regional climate, we studied the reproduction, plant size, and density of sixteen natural populations of four perennial ...

  Citation × Citation Citation Abstract Copy Title: The Performance of Four Native Perennial Forb Species Along a Climate Gradient in Pacific Northwest Prairies Author: Hendricks, Lauren Year: 2016 To determine how Pacific Northwest prairies are influenced by local site factors versus. regional climate, we studied the reproduction, plant size, and density of sixteen natural populations of four perennial forb species native to Pacific Northwest prairies: Ranunculus austro-oreganus, Sidalcea malviflora spp. virgata, Microseris laciniata, and Eriophyllum lanatum. These populations were distributed along a 700 kilometer latitudinal gradient from southern Oregon to Whidbey Island, Washington. We found significant differences in plant size and reproduction among populations for all species, but correlations among edaphic and climate variables and plant size and reproduction were weak. Instead, density was more strongly correlated with both edaphic and climate variables, suggesting that this is a better indicator of long-term demographic processes. Although a few factors are important across species (e.g., nutrient availability and minimum temperature), response is idiosyncratic at the individual species level in Pacific Northwest prairies. Title: The Performance of Four Native Perennial Forb Species Along a Climate Gradient in Pacific Northwest Prairies Author: Hendricks, Lauren Year: 2016 To determine how Pacific Northwest prairies are influenced by local site factors versus. regional climate, we studied the reproduction, plant size, and density of sixteen natural populations of four perennial forb species native to Pacific Northwest prairies: Ranunculus austro-oreganus, Sidalcea malviflora spp. virgata, Microseris laciniata, and Eriophyllum lanatum. These populations were distributed along a 700 kilometer latitudinal gradient from southern Oregon to Whidbey Island, Washington. We found significant differences in plant size and reproduction among populations for all species, but correlations among edaphic and climate variables and plant size and reproduction were weak. Instead, density was more strongly correlated with both edaphic and climate variables, suggesting that this is a better indicator of long-term demographic processes. Although a few factors are important across species (e.g., nutrient availability and minimum temperature), response is idiosyncratic at the individual species level in Pacific Northwest prairies. Close

• 143. [Article] Electron spin resonance of RCHCOR'radicals in X‑irradiated ketone‑urea inclusion compounds

  5 pages

  Citation × Citation Citation Abstract Copy Title: Electron spin resonance of RCHCOR'radicals in X‑irradiated ketone‑urea inclusion compounds Author: Griffith, O. H. Year: 2016, 1965 5 pages Title: Electron spin resonance of RCHCOR'radicals in X‑irradiated ketone‑urea inclusion compounds Author: Griffith, O. H. Year: 2016, 1965 5 pages Close

• 144. [Article] Identifying Genes Required for Cell Division in the Early C. elegans Embryo

  42 pages. A thesis presented to the Department of Biology and the Clark Honors College of the University of Oregon in partial fulfillment of the requirements for degree of Bachelor of Science, Fall 201...

  Citation × Citation Citation Abstract Copy Title: Identifying Genes Required for Cell Division in the Early C. elegans Embryo Author: Standage, Hayley Year: 2014, 2013 42 pages. A thesis presented to the Department of Biology and the Clark Honors College of the University of Oregon in partial fulfillment of the requirements for degree of Bachelor of Science, Fall 2013. Title: Identifying Genes Required for Cell Division in the Early C. elegans Embryo Author: Standage, Hayley Year: 2014, 2013 42 pages. A thesis presented to the Department of Biology and the Clark Honors College of the University of Oregon in partial fulfillment of the requirements for degree of Bachelor of Science, Fall 2013. Close

• 145. [Article] Phases and Phase Transitions in Quantum Ferromagnets

  In this dissertation we study the phases and phase transition properties of quantum ferromagnets and related magnetic materials. We first investigate the effects of an external magnetic field on the Goldstone ...

  Citation × Citation Citation Abstract Copy Title: Phases and Phase Transitions in Quantum Ferromagnets Author: Sang, Yan Year: 2015 In this dissertation we study the phases and phase transition properties of quantum ferromagnets and related magnetic materials. We first investigate the effects of an external magnetic field on the Goldstone mode of a helical magnet, such as MnSi. The field introduces a qualitatively new term into the dispersion relation of the Goldstone mode, which in turn changes the temperature dependences of the contributions of the Goldstone mode to thermodynamic and transport properties. We then study how the phase transition properties of quantum ferromagnets evolve with increasing quenched disorder. We find that there are three distinct regimes for different amounts of disorder. When the disorder is small enough, the quantum ferromagnetic phase transitions is generically of first order. If the disorder is in an intermediate region, the ferromagnetic phase transition is of second order and effectively characterized by mean-field critical exponents. If the disorder is strong enough the ferromagnetic phase transitions are continuous and are characterized by non-mean-field critical exponents. Title: Phases and Phase Transitions in Quantum Ferromagnets Author: Sang, Yan Year: 2015 In this dissertation we study the phases and phase transition properties of quantum ferromagnets and related magnetic materials. We first investigate the effects of an external magnetic field on the Goldstone mode of a helical magnet, such as MnSi. The field introduces a qualitatively new term into the dispersion relation of the Goldstone mode, which in turn changes the temperature dependences of the contributions of the Goldstone mode to thermodynamic and transport properties. We then study how the phase transition properties of quantum ferromagnets evolve with increasing quenched disorder. We find that there are three distinct regimes for different amounts of disorder. When the disorder is small enough, the quantum ferromagnetic phase transitions is generically of first order. If the disorder is in an intermediate region, the ferromagnetic phase transition is of second order and effectively characterized by mean-field critical exponents. If the disorder is strong enough the ferromagnetic phase transitions are continuous and are characterized by non-mean-field critical exponents. Close

• 146. [Article] Photovoltaic Properties of the Gallium Arsenide-PEDOT:PSS Interface

  36 pages. A thesis presented to the Department of Chemistry and the Clark Honors College of the University of Oregon in partial fulfillment of the requirements for degree of Bachelor of Science, Summer ...

  Citation × Citation Citation Abstract Copy Title: Photovoltaic Properties of the Gallium Arsenide-PEDOT:PSS Interface Author: Cramer, Richard Charles Year: 2014 36 pages. A thesis presented to the Department of Chemistry and the Clark Honors College of the University of Oregon in partial fulfillment of the requirements for degree of Bachelor of Science, Summer 2014. Title: Photovoltaic Properties of the Gallium Arsenide-PEDOT:PSS Interface Author: Cramer, Richard Charles Year: 2014 36 pages. A thesis presented to the Department of Chemistry and the Clark Honors College of the University of Oregon in partial fulfillment of the requirements for degree of Bachelor of Science, Summer 2014. Close

• 147. [Article] Water-smart Urban Design: Conserving Potential in Swimming Pools

  Dry weather dominates several U.S. states, and some of them experience even long-term droughts. Yet, more than 10.6 million swimming pools exist in the U.S., and over 43,000 of them are in greater Los ...

  Citation × Citation Citation Abstract Copy Title: Water-smart Urban Design: Conserving Potential in Swimming Pools Author: Antonelli, Eleni Year: 2016 Dry weather dominates several U.S. states, and some of them experience even long-term droughts. Yet, more than 10.6 million swimming pools exist in the U.S., and over 43,000 of them are in greater Los Angeles. Since roughly 100% of their water evaporates on a yearly basis, pool water evaporation accounts for a significant amount of water being wasted every day. Several studies have been conducted to create a proper equation for the evaporation rate on a pool surface, based on the wind speed, water temperature, and relative humidity. This thesis will address a research gap that was found in exploring the way the surroundings of the pool can affect its evaporation rate. In particular, this study examines the relation of the urban design to the evaporation rate of outdoor swimming pools by studying the way the housing type of a neighborhood affects the wind speed over the neighborhood’s pool surfaces. Title: Water-smart Urban Design: Conserving Potential in Swimming Pools Author: Antonelli, Eleni Year: 2016 Dry weather dominates several U.S. states, and some of them experience even long-term droughts. Yet, more than 10.6 million swimming pools exist in the U.S., and over 43,000 of them are in greater Los Angeles. Since roughly 100% of their water evaporates on a yearly basis, pool water evaporation accounts for a significant amount of water being wasted every day. Several studies have been conducted to create a proper equation for the evaporation rate on a pool surface, based on the wind speed, water temperature, and relative humidity. This thesis will address a research gap that was found in exploring the way the surroundings of the pool can affect its evaporation rate. In particular, this study examines the relation of the urban design to the evaporation rate of outdoor swimming pools by studying the way the housing type of a neighborhood affects the wind speed over the neighborhood’s pool surfaces. Close

• 148. [Article] Carbon and Oxygen Isotope Fractionation in Laboratory-Precipitated, Inorganic Calcite

  Carbon and oxygen isotopes in calcite crystals provide a record of the environmental conditions under which the crystals formed. To investigate the influence of temperature, pH, and growth rate on isotope ...

  Citation × Citation Citation Abstract Copy Title: Carbon and Oxygen Isotope Fractionation in Laboratory-Precipitated, Inorganic Calcite Author: Baker, Evan Year: 2015 Carbon and oxygen isotopes in calcite crystals provide a record of the environmental conditions under which the crystals formed. To investigate the influence of temperature, pH, and growth rate on isotope discrimination by calcite, we measured carbon and oxygen isotope fractionation through a series of calcite precipitation experiments at T = 25C and pH = 7.5 - 9.3. We observe that neither the carbon nor oxygen isotope compositions correspond to the theoretical equilibrium isotope fractionation between calcite and solution. We also demonstrate that the fractionation of oxygen isotopes between calcite and water decreases with increasing pH, consistent with available data from experiments in which the enzyme carbonic anhydrase was used. Finally, we compare the carbon and oxygen isotopes of our calcite crystals to those of biogenic carbonates. This thesis includes previously unpublished co-authored material. Title: Carbon and Oxygen Isotope Fractionation in Laboratory-Precipitated, Inorganic Calcite Author: Baker, Evan Year: 2015 Carbon and oxygen isotopes in calcite crystals provide a record of the environmental conditions under which the crystals formed. To investigate the influence of temperature, pH, and growth rate on isotope discrimination by calcite, we measured carbon and oxygen isotope fractionation through a series of calcite precipitation experiments at T = 25C and pH = 7.5 - 9.3. We observe that neither the carbon nor oxygen isotope compositions correspond to the theoretical equilibrium isotope fractionation between calcite and solution. We also demonstrate that the fractionation of oxygen isotopes between calcite and water decreases with increasing pH, consistent with available data from experiments in which the enzyme carbonic anhydrase was used. Finally, we compare the carbon and oxygen isotopes of our calcite crystals to those of biogenic carbonates. This thesis includes previously unpublished co-authored material. Close

• 149. [Article] Understanding the barriers and opportunities for water utility investments in ecosystem services

  2 pages

  Citation × Citation Citation Abstract Copy Title: Understanding the barriers and opportunities for water utility investments in ecosystem services Author: Bennett, Drew E., Duncan, Sally L., Lurie, Susan D., Gosnell, Hannah, Ellison, Autumn Year: 2015, 2014 2 pages Title: Understanding the barriers and opportunities for water utility investments in ecosystem services Author: Bennett, Drew E., Duncan, Sally L., Lurie, Susan D., Gosnell, Hannah, Ellison, Autumn Year: 2015, 2014 2 pages Close

• 150. [Article] Seasonal Dynamics of Methane Pathways Along a Hydrogeomorphic Peatland Gradient

  Northern peatlands occupy a very small proportion of the Earth’s surface but contain nearly a third of the world’s soil organic carbon. These wetland systems produce substantial fluxes of CH4, a potent ...

  Citation × Citation Citation Abstract Copy Title: Seasonal Dynamics of Methane Pathways Along a Hydrogeomorphic Peatland Gradient Author: McAllister, Steven Year: 2016 Northern peatlands occupy a very small proportion of the Earth’s surface but contain nearly a third of the world’s soil organic carbon. These wetland systems produce substantial fluxes of CH4, a potent greenhouse gas, and are expected to experience particularly high annual mean temperature increases as global climate change proceeds, which could result in a significant positive feedback. Using radioisotope labeling, we quantified the rates of two pathways of CH4 production in six sites in northern Michigan along a physiochemical and ecological gradient that characterizes northern peatlands. We found that the rates of these two pathways displayed markedly different dynamics in space and time and that the hydrogenotrophic pathway, previously presumed to be less significant in these systems, can increase substantially and become dominant across the landscape when water tables are high. Quantifying these two pathways provides critical insight into understanding dynamics of CH4 production in northern peatlands. Title: Seasonal Dynamics of Methane Pathways Along a Hydrogeomorphic Peatland Gradient Author: McAllister, Steven Year: 2016 Northern peatlands occupy a very small proportion of the Earth’s surface but contain nearly a third of the world’s soil organic carbon. These wetland systems produce substantial fluxes of CH4, a potent greenhouse gas, and are expected to experience particularly high annual mean temperature increases as global climate change proceeds, which could result in a significant positive feedback. Using radioisotope labeling, we quantified the rates of two pathways of CH4 production in six sites in northern Michigan along a physiochemical and ecological gradient that characterizes northern peatlands. We found that the rates of these two pathways displayed markedly different dynamics in space and time and that the hydrogenotrophic pathway, previously presumed to be less significant in these systems, can increase substantially and become dominant across the landscape when water tables are high. Quantifying these two pathways provides critical insight into understanding dynamics of CH4 production in northern peatlands. Close