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• 2651. [Article] Nonlinear Raman spectroscopy of gases

  Applications of several methods of coherent nonlinear Raman Spectroscopy have been made in this thesis research. The theory and potential of one of these, Photoacoustic Raman Spectroscopy (PARS), is discussed ...

  Citation × Citation Citation Abstract Copy Title: Nonlinear Raman spectroscopy of gases Author: Lundeen, Thomas F. Applications of several methods of coherent nonlinear Raman Spectroscopy have been made in this thesis research. The theory and potential of one of these, Photoacoustic Raman Spectroscopy (PARS), is discussed in chapter two. Experimental results are presented which illustrate the sensitivity of this method and establish sampling conditions for maximum acoustic signals. As part of this work a new photoacoustic Raman cell was designed which is simple to use and gives improved detection capability. Measurements of the nonresonant third order susceptibility of various gases are presented in chapter three. This quantity has been very difficult to determine in absolute terms and is needed to properly account for CARS lineshape distortions which affects frequency and intensity measurements for resonant transitions. Values were measured by first determining nonresonant susceptibilities relative to N₂. Recent linewidth and Raman cross section data were then used to calculate an absolute resonant susceptibility for H₂. Finally, by a separate measurement of the N₂ /H₂ susceptibility ratio, accurate absolute values for the nonresonant third order susceptibility of a number of common gases were deduced. Chapter four describes a study of the rotational relaxation of para hydrogen (and various mixtures) in a supersonic free jet expansion. CARS measurements were used to determine the H₂ rotational temperature in the free jet. One goal of this work was to test several H₂ --- H₂ theoretical interaction potentials. This was done by combining models for the expansion properties of the jet and for relaxation of hydrogen with theoretical values for the cross sections. Rotational temperature profiles of the jet were calculated and the theoretical predictions of several potentials are in good accord with the actual experimental results. Using the complete fluid mechanical model for the expansion process, one can develop a light preference can be developed for the M79 potential of Schaefer and coworkers. Similar calculations were preformed for H₂ --- He mixtures. Title: Nonlinear Raman spectroscopy of gases Author: Lundeen, Thomas F. Applications of several methods of coherent nonlinear Raman Spectroscopy have been made in this thesis research. The theory and potential of one of these, Photoacoustic Raman Spectroscopy (PARS), is discussed in chapter two. Experimental results are presented which illustrate the sensitivity of this method and establish sampling conditions for maximum acoustic signals. As part of this work a new photoacoustic Raman cell was designed which is simple to use and gives improved detection capability. Measurements of the nonresonant third order susceptibility of various gases are presented in chapter three. This quantity has been very difficult to determine in absolute terms and is needed to properly account for CARS lineshape distortions which affects frequency and intensity measurements for resonant transitions. Values were measured by first determining nonresonant susceptibilities relative to N₂. Recent linewidth and Raman cross section data were then used to calculate an absolute resonant susceptibility for H₂. Finally, by a separate measurement of the N₂ /H₂ susceptibility ratio, accurate absolute values for the nonresonant third order susceptibility of a number of common gases were deduced. Chapter four describes a study of the rotational relaxation of para hydrogen (and various mixtures) in a supersonic free jet expansion. CARS measurements were used to determine the H₂ rotational temperature in the free jet. One goal of this work was to test several H₂ --- H₂ theoretical interaction potentials. This was done by combining models for the expansion properties of the jet and for relaxation of hydrogen with theoretical values for the cross sections. Rotational temperature profiles of the jet were calculated and the theoretical predictions of several potentials are in good accord with the actual experimental results. Using the complete fluid mechanical model for the expansion process, one can develop a light preference can be developed for the M79 potential of Schaefer and coworkers. Similar calculations were preformed for H₂ --- He mixtures. Close

• 2652. [Article] Climate and streamflow trends in the Columbia River basin: evidence for ecological and engineering resilience to climate change

  This is an author's peer-reviewed final manuscript, as accepted by the publisher. The published article is copyrighted by Taylor & Francis and can be found at: http://www.tandfonline.com/toc/tato20/cur...

  Citation × Citation Citation Abstract Copy Title: Climate and streamflow trends in the Columbia River basin: evidence for ecological and engineering resilience to climate change Author: Hatcher, Kendra L., Jones, Julia A. This is an author's peer-reviewed final manuscript, as accepted by the publisher. The published article is copyrighted by Taylor & Francis and can be found at: http://www.tandfonline.com/toc/tato20/current#.UkoG0XfVGHc. Title: Climate and streamflow trends in the Columbia River basin: evidence for ecological and engineering resilience to climate change Author: Hatcher, Kendra L., Jones, Julia A. This is an author's peer-reviewed final manuscript, as accepted by the publisher. The published article is copyrighted by Taylor & Francis and can be found at: http://www.tandfonline.com/toc/tato20/current#.UkoG0XfVGHc. Close

• 2653. [Article] Climatic Consequences of a Pine Island Glacier Collapse

  This is the publisher’s final pdf. The published article is copyrighted by the American Meteorological Societyand can be found at: https://www2.ametsoc.org/ams/index.cfm/publications/journals/journal-o...

  Citation × Citation Citation Abstract Copy Title: Climatic Consequences of a Pine Island Glacier Collapse Author: Green, J. A. M., Schmittner, A. This is the publisher’s final pdf. The published article is copyrighted by the American Meteorological Societyand can be found at: https://www2.ametsoc.org/ams/index.cfm/publications/journals/journal-of-climate/ Title: Climatic Consequences of a Pine Island Glacier Collapse Author: Green, J. A. M., Schmittner, A. This is the publisher’s final pdf. The published article is copyrighted by the American Meteorological Societyand can be found at: https://www2.ametsoc.org/ams/index.cfm/publications/journals/journal-of-climate/ Close

• 2654. [Article] Southern Ocean control of glacial AMOC stability and Dansgaard-Oeschger interstadial duration

  Access to this item has been restricted by repository administrators at the request of the publisher until June 30, 2016.

  Citation × Citation Citation Abstract Copy Title: Southern Ocean control of glacial AMOC stability and Dansgaard-Oeschger interstadial duration Author: Buizert, Christo, Schmittner, Andreas Access to this item has been restricted by repository administrators at the request of the publisher until June 30, 2016. Title: Southern Ocean control of glacial AMOC stability and Dansgaard-Oeschger interstadial duration Author: Buizert, Christo, Schmittner, Andreas Access to this item has been restricted by repository administrators at the request of the publisher until June 30, 2016. Close

• 2655. [Article] Multiscale habitat electivity and movement patterns by adult spring chinook salmon in seven river basins of northeast Oregon

  I examined habitat electivity and movement patterns of adult spring chinook salmon at microhabitat and channel unit spatial scales, and seasonal to annual temporal scales in seven streams in the Grande ...

  Citation × Citation Citation Abstract Copy Title: Multiscale habitat electivity and movement patterns by adult spring chinook salmon in seven river basins of northeast Oregon Author: Price, David M. I examined habitat electivity and movement patterns of adult spring chinook salmon at microhabitat and channel unit spatial scales, and seasonal to annual temporal scales in seven streams in the Grande Ronde, John Day, and Imnaha basins. The objective was to compare habitat use and availability among streams, channel units, and microhabitats, and to assess chinook salmon fidelity to those habitats using radio-telemetry. The analyses showed that habitat quality and availability in the seven study streams varied. Each stream posed different physical constraints on adult chinook salmon habitat; this was reflected by the differential use of habitat by salmon among streams. Salmon elected pools almost exclusively in the John Day Basin, whereas pools and riffles were elected in near equal proportion in the Grande Ronde and Inmaha basins. Within streams, use was similar between years. Almost all salmon were observed in association with cover, but the type of cover largely reflected availablity. Chinook salmon elected the deepest depths within channel units (microhabitat scale), but not necessarily the deepest channel units among streams (channel unit scale). Chinook salmon did not elect cooler stream temperatures within channel units in any study stream, except the Middle Fork John Day River. Radio-tagged chinook showed a high fidelity to habitats, except when stream temperatures approached lethal limits. Due to stream specific differences in habitat availability and use, multiscale habitat assessments for individual streams are recommended to increase the success of watershed restoration activities. Title: Multiscale habitat electivity and movement patterns by adult spring chinook salmon in seven river basins of northeast Oregon Author: Price, David M. I examined habitat electivity and movement patterns of adult spring chinook salmon at microhabitat and channel unit spatial scales, and seasonal to annual temporal scales in seven streams in the Grande Ronde, John Day, and Imnaha basins. The objective was to compare habitat use and availability among streams, channel units, and microhabitats, and to assess chinook salmon fidelity to those habitats using radio-telemetry. The analyses showed that habitat quality and availability in the seven study streams varied. Each stream posed different physical constraints on adult chinook salmon habitat; this was reflected by the differential use of habitat by salmon among streams. Salmon elected pools almost exclusively in the John Day Basin, whereas pools and riffles were elected in near equal proportion in the Grande Ronde and Inmaha basins. Within streams, use was similar between years. Almost all salmon were observed in association with cover, but the type of cover largely reflected availablity. Chinook salmon elected the deepest depths within channel units (microhabitat scale), but not necessarily the deepest channel units among streams (channel unit scale). Chinook salmon did not elect cooler stream temperatures within channel units in any study stream, except the Middle Fork John Day River. Radio-tagged chinook showed a high fidelity to habitats, except when stream temperatures approached lethal limits. Due to stream specific differences in habitat availability and use, multiscale habitat assessments for individual streams are recommended to increase the success of watershed restoration activities. Close

• 2656. [Article] Geology of the Greenhorn Mountains, northeastern Oregon

  The Greenhorn Mountains contain a tectonic ally disrupted ophiolite and both arc-derived and pelagic sediments. Age of major sedimentary units within and bordering the thesis area is Early Permian, based ...

  Citation × Citation Citation Abstract Copy Title: Geology of the Greenhorn Mountains, northeastern Oregon Author: Mullen, Ellen Domaratius The Greenhorn Mountains contain a tectonic ally disrupted ophiolite and both arc-derived and pelagic sediments. Age of major sedimentary units within and bordering the thesis area is Early Permian, based upon dates of conodonts and fusulinids from contemporaneous but allocthanous limestones. Sediments near the south boundary of the thesis area previously considered Triassic to Jurassic are re-assigned to the upper-Early Permian Metamorphic grade varies in metasediments from prehnite-pumpellyite in the southern, proximal arc sediments to incipient (disequilibrium) upper greenschist facies in the pelagic series. Pillow lavas associated with Elkhorn Ridge Argillite of the thesis area are only partly spilitized and have original alkalic affinities, probably representing a seamount. High pressure, incipient blueschist metamorphism which retrograded with time to lower greenschist facies is recognized at Bennett Creek, and is correlated with the Mine Ridge Schist. Microprobe analyses of amphiboles and other phases from Bennett Creek, Mine Ridge Schist near Hereford, Oregon, and the lawsonite blueschist of Mitchell, Oregon indicate that in all units pressure decreased and temperature increased with time. Bennett Creek and Mine Ridge Schist metamorphism may be associated with tectonic overpressures followed by burial and increased temperatures with approach of the North American plate, or may be related to subduction. The Mitchell blueschist appears to be a product of subduction. Metagabbro and alpine peridotites of the ophiolite are structurally and lithologically equivalent to the Canyon Mountain Complex, and were tectonically emplaced during Late Triassic time. Late Jurassic intrusives similar to the Bald Mountain batholith range from norite to two-mica granodiorite. Seven discrete intrusions were recognized. Eocene olivine basalt and basaltic andesite exposed in the thesis area are alkalic in affinity and are equivalents of the Clarno Formation. Overlying andesites and dacites are probably Oligocene and may represent the equivalent of John Day volcanism. The Columbia River group consists of two Picture Gorge flows in the western-most portions of the thesis area. Extensive alpine glaciation during the Pleistocene incised deep, U-shaped valleys in the western thesis area. Morainal deposits are common at lower elevations in the area. Deposits of Mazama ash up to six feet in thickness occur along streams of the area. Title: Geology of the Greenhorn Mountains, northeastern Oregon Author: Mullen, Ellen Domaratius The Greenhorn Mountains contain a tectonic ally disrupted ophiolite and both arc-derived and pelagic sediments. Age of major sedimentary units within and bordering the thesis area is Early Permian, based upon dates of conodonts and fusulinids from contemporaneous but allocthanous limestones. Sediments near the south boundary of the thesis area previously considered Triassic to Jurassic are re-assigned to the upper-Early Permian Metamorphic grade varies in metasediments from prehnite-pumpellyite in the southern, proximal arc sediments to incipient (disequilibrium) upper greenschist facies in the pelagic series. Pillow lavas associated with Elkhorn Ridge Argillite of the thesis area are only partly spilitized and have original alkalic affinities, probably representing a seamount. High pressure, incipient blueschist metamorphism which retrograded with time to lower greenschist facies is recognized at Bennett Creek, and is correlated with the Mine Ridge Schist. Microprobe analyses of amphiboles and other phases from Bennett Creek, Mine Ridge Schist near Hereford, Oregon, and the lawsonite blueschist of Mitchell, Oregon indicate that in all units pressure decreased and temperature increased with time. Bennett Creek and Mine Ridge Schist metamorphism may be associated with tectonic overpressures followed by burial and increased temperatures with approach of the North American plate, or may be related to subduction. The Mitchell blueschist appears to be a product of subduction. Metagabbro and alpine peridotites of the ophiolite are structurally and lithologically equivalent to the Canyon Mountain Complex, and were tectonically emplaced during Late Triassic time. Late Jurassic intrusives similar to the Bald Mountain batholith range from norite to two-mica granodiorite. Seven discrete intrusions were recognized. Eocene olivine basalt and basaltic andesite exposed in the thesis area are alkalic in affinity and are equivalents of the Clarno Formation. Overlying andesites and dacites are probably Oligocene and may represent the equivalent of John Day volcanism. The Columbia River group consists of two Picture Gorge flows in the western-most portions of the thesis area. Extensive alpine glaciation during the Pleistocene incised deep, U-shaped valleys in the western thesis area. Morainal deposits are common at lower elevations in the area. Deposits of Mazama ash up to six feet in thickness occur along streams of the area. Close

• 2657. [Article] Characterization of Oxide Growth of Aluminum Alloy 6061 for Nuclear Research and Test Reactors

  Oxide growth is a common phenomenon on aluminum alloy cladding surfaces in nuclear research and test reactors. Without better understanding of oxide growth, excessive oxide build up on the cladding surface ...

  Citation × Citation Citation Abstract Copy Title: Characterization of Oxide Growth of Aluminum Alloy 6061 for Nuclear Research and Test Reactors Author: Wei, Youran Oxide growth is a common phenomenon on aluminum alloy cladding surfaces in nuclear research and test reactors. Without better understanding of oxide growth, excessive oxide build up on the cladding surface reduces heat transfer capability from fuel to coolant and causes safety concerns due to the potential cladding rupture or fuel melt. The purpose of this research is to further the understanding of the oxide growth under the operational conditions in nuclear research and test reactors. The four main objectives of this project are to: 1. Extend the existing database for corrosion of aluminum alloy 6061 2. Evaluate the existing correlations for aluminum alloy corrosion under new experimental conditions 3. Help increase the research reactors' operation safety confidence 4. Evaluate the necessity of the pre-filmed boehmite ( AlO(OH) ) layer. The objectives were accomplished by exposing aluminum alloy 6061 coupons in a test loop operating at low pressure and low temperature. Data from the test loop such as temperature, pressure, pH and exposure time were recorded. SEM (Scanning electron microscope) and ImageJ analysis were used for post experiment examinations to obtain oxide thickness measurement data. Matlab was used to conduct oxide thickness prediction by using existing correlations. Oxide thickness predictions and measurements were compared. EDS (Energy Dispersive Spectroscopy) and XRD (X-Ray Diffraction) analysis were used to identify the oxide chemistry and stoichiometry. Title: Characterization of Oxide Growth of Aluminum Alloy 6061 for Nuclear Research and Test Reactors Author: Wei, Youran Oxide growth is a common phenomenon on aluminum alloy cladding surfaces in nuclear research and test reactors. Without better understanding of oxide growth, excessive oxide build up on the cladding surface reduces heat transfer capability from fuel to coolant and causes safety concerns due to the potential cladding rupture or fuel melt. The purpose of this research is to further the understanding of the oxide growth under the operational conditions in nuclear research and test reactors. The four main objectives of this project are to: 1. Extend the existing database for corrosion of aluminum alloy 6061 2. Evaluate the existing correlations for aluminum alloy corrosion under new experimental conditions 3. Help increase the research reactors' operation safety confidence 4. Evaluate the necessity of the pre-filmed boehmite ( AlO(OH) ) layer. The objectives were accomplished by exposing aluminum alloy 6061 coupons in a test loop operating at low pressure and low temperature. Data from the test loop such as temperature, pressure, pH and exposure time were recorded. SEM (Scanning electron microscope) and ImageJ analysis were used for post experiment examinations to obtain oxide thickness measurement data. Matlab was used to conduct oxide thickness prediction by using existing correlations. Oxide thickness predictions and measurements were compared. EDS (Energy Dispersive Spectroscopy) and XRD (X-Ray Diffraction) analysis were used to identify the oxide chemistry and stoichiometry. Close

• 2658. [Article] Comparison of Short-Term and Long-Term Radiative Feedbacks and Variability in Twentieth-Century Global Climate Model Simulations

  This is the publisher’s final pdf. The published article is copyrighted by the American Meteorological Society and can be found at: http://journals.ametsoc.org/loi/clim.

  Citation × Citation Citation Abstract Copy Title: Comparison of Short-Term and Long-Term Radiative Feedbacks and Variability in Twentieth-Century Global Climate Model Simulations Author: Dalton, Meghan M., Shell, Karen M. This is the publisher’s final pdf. The published article is copyrighted by the American Meteorological Society and can be found at: http://journals.ametsoc.org/loi/clim. Title: Comparison of Short-Term and Long-Term Radiative Feedbacks and Variability in Twentieth-Century Global Climate Model Simulations Author: Dalton, Meghan M., Shell, Karen M. This is the publisher’s final pdf. The published article is copyrighted by the American Meteorological Society and can be found at: http://journals.ametsoc.org/loi/clim. Close

• 2659. [Article] Near-term acceleration of hydroclimatic change in the western U.S.

  This is the publisher’s final pdf. The published article is copyrighted by the American Geophysical Union and can be found at: http://onlinelibrary.wiley.com/journal/10.1002/(ISSN)2169-8996.

  Citation × Citation Citation Abstract Copy Title: Near-term acceleration of hydroclimatic change in the western U.S. Author: Ghosh, Subimal, Bowling, Laura C., Rauscher, Sara A., Diffenbaugh, Noah S., Touma, Danielle, Kao, Shih-Chieh, Ashfaq, Moetasim, Mote, Philip This is the publisher’s final pdf. The published article is copyrighted by the American Geophysical Union and can be found at: http://onlinelibrary.wiley.com/journal/10.1002/(ISSN)2169-8996. Title: Near-term acceleration of hydroclimatic change in the western U.S. Author: Ghosh, Subimal, Bowling, Laura C., Rauscher, Sara A., Diffenbaugh, Noah S., Touma, Danielle, Kao, Shih-Chieh, Ashfaq, Moetasim, Mote, Philip This is the publisher’s final pdf. The published article is copyrighted by the American Geophysical Union and can be found at: http://onlinelibrary.wiley.com/journal/10.1002/(ISSN)2169-8996. Close

• 2660. [Article] A sensitivity-based approach to evaluating future changes in Colorado River Discharge

  This is an author's peer-reviewed final manuscript, as accepted by the publisher. The published article is copyrighted by Springer and can be found at: http://link.springer.com/journal/10584.

  Citation × Citation Citation Abstract Copy Title: A sensitivity-based approach to evaluating future changes in Colorado River Discharge Author: Vano, Julie A., Lettenmaier, Dennis P. This is an author's peer-reviewed final manuscript, as accepted by the publisher. The published article is copyrighted by Springer and can be found at: http://link.springer.com/journal/10584. Title: A sensitivity-based approach to evaluating future changes in Colorado River Discharge Author: Vano, Julie A., Lettenmaier, Dennis P. This is an author's peer-reviewed final manuscript, as accepted by the publisher. The published article is copyrighted by Springer and can be found at: http://link.springer.com/journal/10584. Close