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• 501. [Article] Nitrogen concentration sensitivity study of the lock exchange phenomenon in the high temperature test facility

  The Modular High Temperature Gas-Cooled Reactor (MHTGR) is a graphite moderated reactor that utilizes helium as its coolant. One consideration of importance is how the MHTGR will perform during a Depressurized ...

  Citation × Citation Citation Abstract Copy Title: Nitrogen concentration sensitivity study of the lock exchange phenomenon in the high temperature test facility Author: Utberg, John E., Jr The Modular High Temperature Gas-Cooled Reactor (MHTGR) is a graphite moderated reactor that utilizes helium as its coolant. One consideration of importance is how the MHTGR will perform during a Depressurized Conduction Cooldown (DCC) accident, which generally can be divided into three phases: depressurization, air ingress, and natural circulation. After a rapid depressurization, resulting in a cold air/helium mixture outside the vessel and hot (less dense) helium inside the vessel, a stratified flow of cold ingress gases enters the vessel due to fluid density gradients. Eventually, as ingress gases are introduced into the MHTGR core, buoyancy forces become sufficient to overcome the hydrostatic head of the vessel and begin natural circulation, in which large air ingress is anticipated. The High Temperature Test Facility (HTTF) at Oregon State University (OSU) is a scaled integral test facility based on the Modular High Temperature Gas-Cooled Reactor (MHTGR), and it is designed to model the DCC event and normal operations. Built to provide experimental data for validation of system support codes, the HTTF is a non-nuclear reactor that uses electrical power to analogously represent the heat produced from nuclear fission. As such, the experimental data to be taken from the HTTF will investigate the thermal hydraulic phenomenon occurring in the facility. In this study, a computational fluid dynamics (CFD) model was created to simulate the stratified exchange in the HTTF. Without experimental data available to validate the results, numerous simulations were performed to model physical experiments that are to be performed by the HTTF, including a non-isothermal (hot) gas exchange and an isothermal (cold) room temperature exchange. Title: Nitrogen concentration sensitivity study of the lock exchange phenomenon in the high temperature test facility Author: Utberg, John E., Jr The Modular High Temperature Gas-Cooled Reactor (MHTGR) is a graphite moderated reactor that utilizes helium as its coolant. One consideration of importance is how the MHTGR will perform during a Depressurized Conduction Cooldown (DCC) accident, which generally can be divided into three phases: depressurization, air ingress, and natural circulation. After a rapid depressurization, resulting in a cold air/helium mixture outside the vessel and hot (less dense) helium inside the vessel, a stratified flow of cold ingress gases enters the vessel due to fluid density gradients. Eventually, as ingress gases are introduced into the MHTGR core, buoyancy forces become sufficient to overcome the hydrostatic head of the vessel and begin natural circulation, in which large air ingress is anticipated. The High Temperature Test Facility (HTTF) at Oregon State University (OSU) is a scaled integral test facility based on the Modular High Temperature Gas-Cooled Reactor (MHTGR), and it is designed to model the DCC event and normal operations. Built to provide experimental data for validation of system support codes, the HTTF is a non-nuclear reactor that uses electrical power to analogously represent the heat produced from nuclear fission. As such, the experimental data to be taken from the HTTF will investigate the thermal hydraulic phenomenon occurring in the facility. In this study, a computational fluid dynamics (CFD) model was created to simulate the stratified exchange in the HTTF. Without experimental data available to validate the results, numerous simulations were performed to model physical experiments that are to be performed by the HTTF, including a non-isothermal (hot) gas exchange and an isothermal (cold) room temperature exchange. Close

• 502. [Article] Thermal inactivation studies on some enzymes from Vibrio marinus, an obligately psychrophilic marine bacterium

  Some enzymes of the citric acid cycle and glycolytic pathway in cell-free extracts of Vibrio marinus MP-1 were compared for thermal lability. After one hour of moderate temperature exposure, enzymes of ...

  Citation × Citation Citation Abstract Copy Title: Thermal inactivation studies on some enzymes from Vibrio marinus, an obligately psychrophilic marine bacterium Author: Mathemeier, Paul Fredrick Some enzymes of the citric acid cycle and glycolytic pathway in cell-free extracts of Vibrio marinus MP-1 were compared for thermal lability. After one hour of moderate temperature exposure, enzymes of both pathways rapidly lost catalytic activity. For all but one enzyme, 50 percent remaining activity occurred near an averaged temperature of 27 C. Succinic dehydrogenase was remarkably unstable, being 50 percent inactivated at 16 C. Complete loss of enzymatic activity for the TCA and glycolytic enzymes took place at an averaged temperature of 32 C. Lactic dehydrogenase was the most thermostable as evidenced by activity up to 39 C. Several of the "psychrophilic" enzymes (hexokinase, aldolase, and lactic dehydrogenase) produced greater activity in the presence of sodium chloride as opposed to tris-HC1. Suspending the enzyme preparations in sodium chloride resulted in an increased thermal stability. The 50 percent remaining activity took place at 1 C to 15 C higher with an average of 32 C. Complete loss of catalytic function averaged 2 C higher for the sodium chloride suspended enzyme. There was noticeably less difference in thermal protection by sodium chloride at temperatures above the region of 50 percent remaining activity. The effects of salt are explained on the basis of increased activity coefficients in solution. The behavior of lactic dehydrogenase on moderate temperature exposure suggested the existence of isozymes, or that denaturation occurred in three major steps, each with a different rate. The low temperature requirement of all the enzymes under investigation, together with the ionic requirement of hexokinase and the relatively high level of phosphoglucose isomerase were suggested as possible factors controlling the obligate psychrophile's activities. Furthermore, the diverse influence of moderate temperature exposure on each enzyme (whether in buffer of sodium chloride) could alter differentially the cell's catalytic processes so that they could no longer operate in synchrony. Comparison with enzymes from other sources indicated the tricarboxylic acid cycle and glycolytic enzymes of Vibrio marinus MP-1 to be conspicuously thermal labile. Title: Thermal inactivation studies on some enzymes from Vibrio marinus, an obligately psychrophilic marine bacterium Author: Mathemeier, Paul Fredrick Some enzymes of the citric acid cycle and glycolytic pathway in cell-free extracts of Vibrio marinus MP-1 were compared for thermal lability. After one hour of moderate temperature exposure, enzymes of both pathways rapidly lost catalytic activity. For all but one enzyme, 50 percent remaining activity occurred near an averaged temperature of 27 C. Succinic dehydrogenase was remarkably unstable, being 50 percent inactivated at 16 C. Complete loss of enzymatic activity for the TCA and glycolytic enzymes took place at an averaged temperature of 32 C. Lactic dehydrogenase was the most thermostable as evidenced by activity up to 39 C. Several of the "psychrophilic" enzymes (hexokinase, aldolase, and lactic dehydrogenase) produced greater activity in the presence of sodium chloride as opposed to tris-HC1. Suspending the enzyme preparations in sodium chloride resulted in an increased thermal stability. The 50 percent remaining activity took place at 1 C to 15 C higher with an average of 32 C. Complete loss of catalytic function averaged 2 C higher for the sodium chloride suspended enzyme. There was noticeably less difference in thermal protection by sodium chloride at temperatures above the region of 50 percent remaining activity. The effects of salt are explained on the basis of increased activity coefficients in solution. The behavior of lactic dehydrogenase on moderate temperature exposure suggested the existence of isozymes, or that denaturation occurred in three major steps, each with a different rate. The low temperature requirement of all the enzymes under investigation, together with the ionic requirement of hexokinase and the relatively high level of phosphoglucose isomerase were suggested as possible factors controlling the obligate psychrophile's activities. Furthermore, the diverse influence of moderate temperature exposure on each enzyme (whether in buffer of sodium chloride) could alter differentially the cell's catalytic processes so that they could no longer operate in synchrony. Comparison with enzymes from other sources indicated the tricarboxylic acid cycle and glycolytic enzymes of Vibrio marinus MP-1 to be conspicuously thermal labile. Close

• 503. [Article] Dielectric properties of BaTiO3–Bi(Zn1/2Ti1/2)O3–NaNbO3 solid solutions

  To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. This is the publisher’s final pdf. The published article is copyrighted by Springer ...

  Citation × Citation Citation Abstract Copy Title: Dielectric properties of BaTiO3–Bi(Zn1/2Ti1/2)O3–NaNbO3 solid solutions Author: Brown-Shaklee, Harlan J., Brennecka, Geoff L., Cann, David P., Raengthon, Natthaphon To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. This is the publisher’s final pdf. The published article is copyrighted by Springer and can be found at: http://www.springer.com/?SGWID=0-102-0-0-0. Title: Dielectric properties of BaTiO3–Bi(Zn1/2Ti1/2)O3–NaNbO3 solid solutions Author: Brown-Shaklee, Harlan J., Brennecka, Geoff L., Cann, David P., Raengthon, Natthaphon To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. This is the publisher’s final pdf. The published article is copyrighted by Springer and can be found at: http://www.springer.com/?SGWID=0-102-0-0-0. Close

• 504. [Article] Assessing Streamflow Response to Climate Change: Why Geology Matters

  Presented at The Oregon Water Conference, May 24-25, 2011, Corvallis, OR.

  Citation × Citation Citation Abstract Copy Title: Assessing Streamflow Response to Climate Change: Why Geology Matters Author: Mayer, Tim Year: 2011 Presented at The Oregon Water Conference, May 24-25, 2011, Corvallis, OR. Title: Assessing Streamflow Response to Climate Change: Why Geology Matters Author: Mayer, Tim Year: 2011 Presented at The Oregon Water Conference, May 24-25, 2011, Corvallis, OR. Close

• 505. [Article] Projected temperature and precipitation changes for Corvallis and Los Angeles for the 2030-2059 period using the Hadley Center's regional climate model (HadRM3P).

  Average monthly temperatures (maximum and minimum) and precipitation patterns are expected to change as a direct consequence of anthropogenic climate change. Temperatures are expected to be warmer in the ...

  Citation × Citation Citation Abstract Copy Title: Projected temperature and precipitation changes for Corvallis and Los Angeles for the 2030-2059 period using the Hadley Center's regional climate model (HadRM3P). Author: Cheema, Karandeep Singh Average monthly temperatures (maximum and minimum) and precipitation patterns are expected to change as a direct consequence of anthropogenic climate change. Temperatures are expected to be warmer in the future but precise estimates vary depending on factors like number of ensembles and emission scenario. For this study, we used 100 ensembles to simulate a recent historical period (Dec. 1985-Nov 2014) and a future climate scenario (Dec. 2030-Nov. 2059) for two cities: Corvallis, OR and Los Angeles, CA. Atmospheric forcings followed the RCP 4.5 scenario. We used results from the simulations to compare temperature and precipitation changes between the two periods for both cities. Average monthly temperatures (maximum and minimum) increased for both cities. Both cities would experience an increase in number of days above 90 °F (14 for Corvallis and 18 more days for Los Angeles). For Corvallis, average annual temperature increased from 12.8 ± 0.3°? to 14.4 ± 0.3 °?. Average annual precipitation increased from 942.0 mm to 994.0 mm (p-value: 10−23). Likewise, for Los Angeles, average annual temperature increased from 18.1 ± 0.3°? to 19.5 ± 0.3 °? and average annual precipitation changed from 265.0 mm to 260.0 mm (p-value: 0.32). We further analyzed changes in precipitation in terms of changes in frequency and intensity. Frequency and intensity of precipitation increased in winter months for Corvallis while non-uniform patterns were seen for Los Angeles. Summer precipitation decreased in terms of frequency and intensity of precipitation events for both cities. Title: Projected temperature and precipitation changes for Corvallis and Los Angeles for the 2030-2059 period using the Hadley Center's regional climate model (HadRM3P). Author: Cheema, Karandeep Singh Average monthly temperatures (maximum and minimum) and precipitation patterns are expected to change as a direct consequence of anthropogenic climate change. Temperatures are expected to be warmer in the future but precise estimates vary depending on factors like number of ensembles and emission scenario. For this study, we used 100 ensembles to simulate a recent historical period (Dec. 1985-Nov 2014) and a future climate scenario (Dec. 2030-Nov. 2059) for two cities: Corvallis, OR and Los Angeles, CA. Atmospheric forcings followed the RCP 4.5 scenario. We used results from the simulations to compare temperature and precipitation changes between the two periods for both cities. Average monthly temperatures (maximum and minimum) increased for both cities. Both cities would experience an increase in number of days above 90 °F (14 for Corvallis and 18 more days for Los Angeles). For Corvallis, average annual temperature increased from 12.8 ± 0.3°? to 14.4 ± 0.3 °?. Average annual precipitation increased from 942.0 mm to 994.0 mm (p-value: 10−23). Likewise, for Los Angeles, average annual temperature increased from 18.1 ± 0.3°? to 19.5 ± 0.3 °? and average annual precipitation changed from 265.0 mm to 260.0 mm (p-value: 0.32). We further analyzed changes in precipitation in terms of changes in frequency and intensity. Frequency and intensity of precipitation increased in winter months for Corvallis while non-uniform patterns were seen for Los Angeles. Summer precipitation decreased in terms of frequency and intensity of precipitation events for both cities. Close

• 506. [Article] Using infrared canopy temperature and leaf water potential for irrigation scheduling in peppermint (Mentha piperita L.)

  Several methods of infering plant water stress for irrigation scheduling are based upon measurements of the environment in which the plants grow. These measurements include parameters such as soil water ...

  Citation × Citation Citation Abstract Copy Title: Using infrared canopy temperature and leaf water potential for irrigation scheduling in peppermint (Mentha piperita L.) Author: Gallardo, Ivan T. Several methods of infering plant water stress for irrigation scheduling are based upon measurements of the environment in which the plants grow. These measurements include parameters such as soil water content, air temperature, pan evaporation and incident radiation. It is hypothesized that improved estimates of plant water deficit can be obtained by direct measurements made on the plants. The main objective of this study was to test the performance of measurements of canopy temperature and leaf water potential for irrigation scheduling. This study seeks to establish whether a correlation exists between these monitoring methods and measurements of soil moisture content, leaf area, and evapotranspiration. The experiments were conducted in first-year peppermint irrigated at five different rates. Canopy and air temperatures were measured with a hand-held infrared thermometer. Leaf water potential was measured with a pressure bomb. A non-stressed baseline for the difference between canopy temperature and air temperature using data from well-watered plants was used together with the vapor pressure deficit to determine the crop water stress index (CWSI). The results of this study show that the CWSI is well correlated to evapotranspiration deficit and is useful for irrigation scheduling. The relationship between leaf area yield and CWSI in peppermint was described by a quadratic function. Leaf water potential varied during the day in such a way that it was not possible to establish a relationship with water stress, differences in soil moisture content, or different irrigation levels. Leaf water potential was influenced by the daily weather conditions and represented the current demand more than the cumulative demand. The results of this study indicate that mid-day pressure bomb measurements cannot be used in irrigation scheduling. Predawn measurements of leaf water potential were stable, were well correlated with the different irrigation levels and soil moisture content, and therefore may be useful in irrigation scheduling. Title: Using infrared canopy temperature and leaf water potential for irrigation scheduling in peppermint (Mentha piperita L.) Author: Gallardo, Ivan T. Several methods of infering plant water stress for irrigation scheduling are based upon measurements of the environment in which the plants grow. These measurements include parameters such as soil water content, air temperature, pan evaporation and incident radiation. It is hypothesized that improved estimates of plant water deficit can be obtained by direct measurements made on the plants. The main objective of this study was to test the performance of measurements of canopy temperature and leaf water potential for irrigation scheduling. This study seeks to establish whether a correlation exists between these monitoring methods and measurements of soil moisture content, leaf area, and evapotranspiration. The experiments were conducted in first-year peppermint irrigated at five different rates. Canopy and air temperatures were measured with a hand-held infrared thermometer. Leaf water potential was measured with a pressure bomb. A non-stressed baseline for the difference between canopy temperature and air temperature using data from well-watered plants was used together with the vapor pressure deficit to determine the crop water stress index (CWSI). The results of this study show that the CWSI is well correlated to evapotranspiration deficit and is useful for irrigation scheduling. The relationship between leaf area yield and CWSI in peppermint was described by a quadratic function. Leaf water potential varied during the day in such a way that it was not possible to establish a relationship with water stress, differences in soil moisture content, or different irrigation levels. Leaf water potential was influenced by the daily weather conditions and represented the current demand more than the cumulative demand. The results of this study indicate that mid-day pressure bomb measurements cannot be used in irrigation scheduling. Predawn measurements of leaf water potential were stable, were well correlated with the different irrigation levels and soil moisture content, and therefore may be useful in irrigation scheduling. Close

• 507. [Article] Temperature Changes in Human Skeletal Muscle during Single Leg Dynamic Knee Extension Exercise

  49 pages. A thesis presented to the Department of Uman Physiology and the Clark Honors College of the University of Oregon in partial fulfillment of the requirements for degree of Bachelor of Arts, Summer ...

  Citation × Citation Citation Abstract Copy Title: Temperature Changes in Human Skeletal Muscle during Single Leg Dynamic Knee Extension Exercise Author: Peck, Mairin Year: 2015 49 pages. A thesis presented to the Department of Uman Physiology and the Clark Honors College of the University of Oregon in partial fulfillment of the requirements for degree of Bachelor of Arts, Summer 2015. Title: Temperature Changes in Human Skeletal Muscle during Single Leg Dynamic Knee Extension Exercise Author: Peck, Mairin Year: 2015 49 pages. A thesis presented to the Department of Uman Physiology and the Clark Honors College of the University of Oregon in partial fulfillment of the requirements for degree of Bachelor of Arts, Summer 2015. Close

• 508. [Article] Does temperature affect the accuracy of vented pressure transducer in fine-scale water level measurement?

  This is the publisher’s final pdf. The published article is copyrighted by the author(s) and published by Copernicus Publications on behalf of the European Geosciences Union. The published article can ...

  Citation × Citation Citation Abstract Copy Title: Does temperature affect the accuracy of vented pressure transducer in fine-scale water level measurement? Author: Higgins, C. W., Liu, Z This is the publisher’s final pdf. The published article is copyrighted by the author(s) and published by Copernicus Publications on behalf of the European Geosciences Union. The published article can be found at: http://www.geoscientific-instrumentation-methods-and-data-systems.net/ Title: Does temperature affect the accuracy of vented pressure transducer in fine-scale water level measurement? Author: Higgins, C. W., Liu, Z This is the publisher’s final pdf. The published article is copyrighted by the author(s) and published by Copernicus Publications on behalf of the European Geosciences Union. The published article can be found at: http://www.geoscientific-instrumentation-methods-and-data-systems.net/ Close

• 509. [Article] Does temperature affect the accuracy of vented pressure transducer in fine-scale water level measurement?

  The final revised paper is available at: http://hdl.handle.net/1957/56519

  Citation × Citation Citation Abstract Copy Title: Does temperature affect the accuracy of vented pressure transducer in fine-scale water level measurement? Author: Liu, Z., Higgins, C. W. The final revised paper is available at: http://hdl.handle.net/1957/56519 Title: Does temperature affect the accuracy of vented pressure transducer in fine-scale water level measurement? Author: Liu, Z., Higgins, C. W. The final revised paper is available at: http://hdl.handle.net/1957/56519 Close

• 510. [Article] Development of a microchannel device for adsorption cooling application

  Single-layer and three-layer microchannel adsorption devices were fabricated by procedure that was newly developed. Aluminum was chosen for metal housing while the adsorption pair was silica gel and water. ...

  Citation × Citation Citation Abstract Copy Title: Development of a microchannel device for adsorption cooling application Author: Asumpinpong, Kasidid Single-layer and three-layer microchannel adsorption devices were fabricated by procedure that was newly developed. Aluminum was chosen for metal housing while the adsorption pair was silica gel and water. Each adsorption layer contained two layers of 250 μm-thick silica gel. Both silica gel layers opened to the same layer of adsorption channels. The layers of air flow channels were placed between two adsorption layers, including over the top and below the bottom adsorption layers. Each layer of adsorption channels and air flow channels contained array of six microchannels. Each microchannel was 400 μm tall, 5.8 mm wide and 4.4 cm long. The device was bonded by B-staged epoxy thin film at moderate temperature of 120°C. The overall dimensions of the fabricated device were 5 cm x 5 cm x 10.2 mm for the three-layer device. A maximum coefficient of performance (COP) of 0.506 was achieved at the evaporator temperature of 22°C, adsorption temperature of 23°C and desorption temperature of 50°C. The highest specific cooling power (SCP) obtained was 601 W/kg silica gel when desorption temperature was increased to 70°C The overall performance of the device improved slightly when the air flow rate was increased. The COP increased by a factor of 2.4 when the number of adsorption layers increased from 1 to 3. The results from simulation model agreed with the experimental results and also showed that both COP and SCP decreased drastically when evaporator temperature was far below the adsorption temperature. Title: Development of a microchannel device for adsorption cooling application Author: Asumpinpong, Kasidid Single-layer and three-layer microchannel adsorption devices were fabricated by procedure that was newly developed. Aluminum was chosen for metal housing while the adsorption pair was silica gel and water. Each adsorption layer contained two layers of 250 μm-thick silica gel. Both silica gel layers opened to the same layer of adsorption channels. The layers of air flow channels were placed between two adsorption layers, including over the top and below the bottom adsorption layers. Each layer of adsorption channels and air flow channels contained array of six microchannels. Each microchannel was 400 μm tall, 5.8 mm wide and 4.4 cm long. The device was bonded by B-staged epoxy thin film at moderate temperature of 120°C. The overall dimensions of the fabricated device were 5 cm x 5 cm x 10.2 mm for the three-layer device. A maximum coefficient of performance (COP) of 0.506 was achieved at the evaporator temperature of 22°C, adsorption temperature of 23°C and desorption temperature of 50°C. The highest specific cooling power (SCP) obtained was 601 W/kg silica gel when desorption temperature was increased to 70°C The overall performance of the device improved slightly when the air flow rate was increased. The COP increased by a factor of 2.4 when the number of adsorption layers increased from 1 to 3. The results from simulation model agreed with the experimental results and also showed that both COP and SCP decreased drastically when evaporator temperature was far below the adsorption temperature. Close