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Assessing Linkages Among Landscape Characteristics, Stream Habitat, And Macroinvertebrate Communities In The Idaho Batholith Ecoregion, Andrew C. Hill Dec 2010

Assessing Linkages Among Landscape Characteristics, Stream Habitat, And Macroinvertebrate Communities In The Idaho Batholith Ecoregion, Andrew C. Hill

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Understanding the composition of lotic communities and the landscape processes and habitat characteristics that shape them is one of the main challenges confronting stream ecologists. In order to better understand the linkages among landscape processes, stream habitat, and biological communities and to understand how accurately our measurements represent important factors influencing biological communities, it is important to test explicit hypotheses regarding these linkages. Increasing our understanding of aquatic communities in a hierarchical context and recognizing how well our measurements represent factors structuring aquatic communities will help managers better evaluate the influence of land management practices on aquatic ecosystems, direct conservation …


Temperature And Variability Of Three Ionian Volcanoes, Daniel R. Allen Aug 2010

Temperature And Variability Of Three Ionian Volcanoes, Daniel R. Allen

Theses and Dissertations

Cassini spacecraft images of Io obtained during its flyby of Jupiter in late 2000 and early 2001 were used to determine the lava composition and eruption style of three faint hotspots, Pillan, Wayland, and Loki. We found a maximum color temperature of 1130+/-289 K for Pillan and maximum color temperatures of 1297+/-289 K and 1387+/-287 K for Wayland and Loki, respectively. These temperatures are suggestive of basaltic lava. The temperatures with the best signal-to-noise ratios also suggested basaltic lava and were found to be 780+/-189 K, 1116+/-250 K, and 1017+/-177 K for Pillan, Wayland, and Loki, respectively. Pillan showed increased …


Reversible Record Breaking And Variability: Temperature Distributions Across The Globe, Amalia Anderson, Alexander Kostinski Aug 2010

Reversible Record Breaking And Variability: Temperature Distributions Across The Globe, Amalia Anderson, Alexander Kostinski

Department of Physics Publications

Based on counts of record highs and lows, and employing reversibility in time, an approach to examining natural variability is proposed. The focus is on intrinsic variability; that is, variance separated from the trend in the mean. A variability index α is suggested and studied for an ensemble of monthly temperature time series around the globe. Deviation of 〈α〉 (mean α) from zero, for an ensemble of time series, signifies a variance trend in a distribution-independent manner. For 15 635 monthly temperature time series from different geographical locations (Global Historical Climatology Network), each time series about a …


Robust Isothermal Electric Control Of Exchange Bias At Room Temperature, Xi He, Yi Wang, Christian Binek, Peter A. Dowben Jun 2010

Robust Isothermal Electric Control Of Exchange Bias At Room Temperature, Xi He, Yi Wang, Christian Binek, Peter A. Dowben

Christian Binek Publications

Voltage-controlled spin electronics is crucial for continued progress in information technology. It aims at reduced power consumption, increased integration density and enhanced functionality where non-volatile memory is combined with highspeed logical processing. Promising spintronic device concepts use the electric control of interface and surface magnetization. From the combination of magnetometry, spin-polarized photoemission spectroscopy, symmetry arguments and first-principles calculations, we show that the (0001) surface of magnetoelectric Cr2O3 has a roughness-insensitive, electrically switchable magnetization. Using a ferromagnetic Pd/Co multilayer deposited on the (0001) surface of a Cr2O3 single crystal, we achieve reversible, room-temperature isothermal switching of the exchange-bias field between positive …


Quantum Criticality Due To Incipient Phase Separation In The Two-Dimensional Hubbard Model, Ehsan Khatami, K. Mikelsons, D. Galanakis, A. Macridin, J. Moreno, R. Scalettar, M. Jarrell May 2010

Quantum Criticality Due To Incipient Phase Separation In The Two-Dimensional Hubbard Model, Ehsan Khatami, K. Mikelsons, D. Galanakis, A. Macridin, J. Moreno, R. Scalettar, M. Jarrell

Faculty Publications

We investigate the two-dimensional Hubbard model with next-nearest-neighbor hopping, t′, using the dynamical cluster approximation. We confirm the existence of a first-order phase-separation transition terminating at a second-order critical point at filling nc(t′) and temperature Tps(t′). We find that as t′ approaches zero, Tps(t′) vanishes and nc(t′) approaches the filling associated with the quantum critical point separating the Fermi liquid from the pseudogap phase. We propose that the quantum critical point under the superconducting dome is the zero-temperature limit of the line of second-order critical points.


On The Nature Of Winter Cooling And The Recent Temperature Shift On The Northern Gulf Of Alaska Shelf, Markus A. Janout, Thomas J. Weingartner, Thomas C. Royer, Seth L. Danielson Jan 2010

On The Nature Of Winter Cooling And The Recent Temperature Shift On The Northern Gulf Of Alaska Shelf, Markus A. Janout, Thomas J. Weingartner, Thomas C. Royer, Seth L. Danielson

CCPO Publications

[1] In spring 2006 and 2007, northern Gulf of Alaska (GOA) shelf waters were ∼1.5°C below average throughout the similar to ∼250 m deep shelf and the salinity-dependent winter stratification was anomalously weak due to above (below) average surface (bottom) salinities. Spring 2007 and 2008 temperatures were also similar to ∼-1.5°C below average, but the anomalies were confined to the upper 100 m due to moderate salt stratification. Shelf temperatures in these 2 years were among the lowest observed since the early 1970s, thus interrupting an approximately 30-year warming trend. We examined winter cooling processes using historical conductivity-temperature-depth (CTD) profiles …


Temporal Dynamics Of Group Size And Sexual Segregation In Ibex, N. J. Singh, S. Amgalanbaatar, Richard P. Reading Jan 2010

Temporal Dynamics Of Group Size And Sexual Segregation In Ibex, N. J. Singh, S. Amgalanbaatar, Richard P. Reading

Erforschung biologischer Ressourcen der Mongolei / Exploration into the Biological Resources of Mongolia, ISSN 0440-1298

Group size is an important variable describing behavioral ecology of animals. A variety of factors such as habitat characteristics, life history, spatio-temporal resource dynamics, population density, predation risk, competition with kin, and social learning often determine group size in large mammals. We studied temporal dynamics of group size in Siberian ibex (Capra sibirica) in a protected area in Mongolia. We measured monthly and yearly variations in typical group size and used the sexual segregation and aggregation statistic to assess sexual segregation. Ibex formed the largest groups in November and smallest groups in July. However, group sizes did not …


Land Surface Brightness Temperature Modeling Using Solar Insolation, Haroon Stephen, Sajjad Ahmad, Thomas C. Piechota Jan 2010

Land Surface Brightness Temperature Modeling Using Solar Insolation, Haroon Stephen, Sajjad Ahmad, Thomas C. Piechota

Public Policy and Leadership Faculty Publications

Retrieval of land surface emissivity and temperature from microwave brightness temperature data is a complex problem. The diurnal variation of temperature due to the diurnal cycle of solar radiation and weather conditions makes this problem even more challenging. In this paper, we use solar radiation in modeling the temporal variation of the brightness temperature state of the surface. Solar insolation modeling is used to estimate the diurnal variation of land surface brightness temperature. Solar radiation and brightness temperature are linked through temperature of the surface which is derived based on the radiation balance equation. The temperature state model behaves consistent …


Reactions Of The Cn Radical With Benzene And Toluene: Product Detection And Low-Temperature Kinetics, Adam J. Trevitt, Fabien Goulay, Craig A. Taatjes, David L. Osborn, Stephen R. Leone Jan 2010

Reactions Of The Cn Radical With Benzene And Toluene: Product Detection And Low-Temperature Kinetics, Adam J. Trevitt, Fabien Goulay, Craig A. Taatjes, David L. Osborn, Stephen R. Leone

Faculty of Science - Papers (Archive)

Low-temperature rate coefficients are measured for the CN + benzene and CN + toluene reactions using the pulsed Laval nozzle expansion technique coupled with laser-induced fluorescence detection. The CN + benzene reaction rate coefficient at 105, 165, and 295 K is found to be relatively constant over this temperature range, (3.9−4.9) × 10−10 cm3 molecule−1 s−1. These rapid kinetics, along with the observed negligible temperature dependence, are consistent with a barrierless reaction entrance channel and reaction efficiencies approaching unity. The CN + toluene reaction is measured to have a rate coefficient of 1.3 × 10−10 cm3 molecule−1 s−1 at 105 …


Effects Of Soil Temperature Regimes After Fire On Seed Dormancy And Germination In Six Australian Fabaceae Species, Victor Santana, Ross A. Bradstock, Mark Ooi, Andrew J. Denham, Tony D. Auld, M Baeza Jan 2010

Effects Of Soil Temperature Regimes After Fire On Seed Dormancy And Germination In Six Australian Fabaceae Species, Victor Santana, Ross A. Bradstock, Mark Ooi, Andrew J. Denham, Tony D. Auld, M Baeza

Faculty of Science - Papers (Archive)

In addition to direct fire cues such as heat, smoke and charred wood, the passage of fire leads indirectly to changes in environmental conditions which may be able to break physical dormancy in hard-coated seeds. After a fire, the open canopy and the burnt material lying on the surface alter the thermal properties of the soil, resulting in elevated soil temperatures for long periods of time. We simulated daily temperature regimes experienced at different depths of soil profile after a summer fire. Our aim was to determine whether these temperature regimes and the duration of exposure (5, 15 and 30 …


Reaction Of The C2h Radical With 1-Butyne (C4h6): Low Temperature Kinetics And Isomer-Specific Product Detection, Satchin Soorkia, Adam J. Trevitt, Talitha M. Selby, David L. Osborn, Craig A. Taatjes, Kevin R. Wilson, Stephen R. Leone Jan 2010

Reaction Of The C2h Radical With 1-Butyne (C4h6): Low Temperature Kinetics And Isomer-Specific Product Detection, Satchin Soorkia, Adam J. Trevitt, Talitha M. Selby, David L. Osborn, Craig A. Taatjes, Kevin R. Wilson, Stephen R. Leone

Faculty of Science - Papers (Archive)

No abstract provided.


Magnetotransport Of La0.70ca0.3-Xsrxmno3(Ag): A Potential Room Temperature Bolometer And Magnetic Sensor, V P. Awana, Rahul Tripathi, Neeraj Kumar, H Kishan, G V. Bhalla, Rong Zeng, L.S Sharth Chandra, V Ganesan, H U. Habermeier Jan 2010

Magnetotransport Of La0.70ca0.3-Xsrxmno3(Ag): A Potential Room Temperature Bolometer And Magnetic Sensor, V P. Awana, Rahul Tripathi, Neeraj Kumar, H Kishan, G V. Bhalla, Rong Zeng, L.S Sharth Chandra, V Ganesan, H U. Habermeier

Australian Institute for Innovative Materials - Papers

Here we report the optimized magnetotransport properties of polycrystalline La0.70Ca0.3−xSrxMnO3 and their composites with Ag. The optimization was carried out by varying the Sr and Ag contents simultaneously to achieve large temperature coefficient of resistance (TCR) as well as low field magnetoresistance (MR) at room temperature. Sharpest paramagnetic (PM)-ferromagnetic (FM) and insulator-metal (IM) transition is observed in the vicinity of the room temperature (TC≈300 K ≈TIM) for the composition La0.70Ca0.20Sr0.10MnO3:Ag0.20. Partial substitution of larger Sr2+ ions at the …


The Development Of Scalable Pump Techniques For Gg Iag Fiber Lasers And Passive Athermalization Techniques For Solid State Laser, William Hageman Jan 2010

The Development Of Scalable Pump Techniques For Gg Iag Fiber Lasers And Passive Athermalization Techniques For Solid State Laser, William Hageman

Electronic Theses and Dissertations

This dissertation consists of two parts: research pertaining to the development of scalable pump techniques for gain guided index-antiguided fiber lasers and research relating to the development of passive athermalization schemes for solid state lasers. The first section primarily details the development of a side pump scheme that allows for power scaling of gain-guided index anti-guided fibers. While these fibers have been demonstrated in past research, none have used a pump technology capable of pumping with the efficiencies, uniformity, and necessary length to allow for scaling of the fiber lasers to high output powers. The side pumped scheme developed in …


Temperature And Frequency Dependent Conduction Mechanisms Within Bulk Carbon Nanotube Materials, John Simmons Bulmer Jan 2010

Temperature And Frequency Dependent Conduction Mechanisms Within Bulk Carbon Nanotube Materials, John Simmons Bulmer

Browse all Theses and Dissertations

The resistance of three types of bulk carbon nanotube (CNT) materials (floating catalyst CNT yarn, forest grown CNT yarn, and super acid spun CNT fiber) was measured from room temperature to 900 C. Fitting the curves to established conduction equations for disordered materials, competing conduction mechanisms pertaining to the material could be determined. Floating catalyst CNT yarn displayed both semiconductive and metallic isotropic behavior with a resistance minimum, similar to the behavior of crystalline graphite. It was found that, at room temperature, the semiconducting contribution-most likely junctions between CNTs-accounted for 99.99% of the overall resistance. The resistance of forest grown …