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Studies of Band Structure and Free Carrier Scattering in Transparent Conducting Oxides Based on Combined Measurements of Electron Transport Phenomena (open access)

Studies of Band Structure and Free Carrier Scattering in Transparent Conducting Oxides Based on Combined Measurements of Electron Transport Phenomena

Experimental methods are discussed for studying band structure, effective mass, and other electronic properties relevant to mobility, including scattering mechanisms, relaxation time, and the influence of grain boundaries (GBs) in polycrystalline transparent conducting oxide (TCO) films. Impedance spectroscopy permits evaluation of the GB potential barrier height and density-of-states. These studies enable an estimate of the limiting mobility achievable for practical transparent conducting oxides to be made. The equipment for measurement of the four transport coefficients is discussed, and examples of its application to films of ZnO, SnO2, and Cd2SnO4 are given.
Date: October 31, 2000
Creator: Kaydanov, V. I.; Coutts, T. J. & Young, D. L.
System: The UNT Digital Library
MD Simulations of Carbonmonoxy Myoglobin and Calculations of Heme CD (open access)

MD Simulations of Carbonmonoxy Myoglobin and Calculations of Heme CD

None
Date: October 31, 2000
Creator: Woody, Robert W.; Kiefl, Christoph; Sreerama, Narasimha; Lu, Yi; Qiu, Yan & Shelnutt, John A.
System: The UNT Digital Library
Estimates of dispersive effects in a bent NLC Main Linac (open access)

Estimates of dispersive effects in a bent NLC Main Linac

An alternative being considered for the Next Linear Collider (NLC) is not to tunnel in a straight line but to bend the Main Linac into an arc so as to follow a gravitational equipotential. The authors begin here an examination of the effects that this would have on vertical dispersion, with its attendant consequences on synchrotron radiation and emittance growth by looking at two scenarios: a gentle continuous bending of the beam to follow an equipotential surface, and an introduction of sharp bends at a few sites in the linac so as to reduce the maximum sagitta produced.
Date: October 31, 2000
Creator: Michelotti, Michael Syphers and Leo
System: The UNT Digital Library
IFSAR for the Rapid Terrain Visualization Demonstration (open access)

IFSAR for the Rapid Terrain Visualization Demonstration

The Rapid Terrain Visualization Advanced Concept Technology Demonstration (RTV-ACTD) is designed to demonstrate the technologies and infrastructure to meet the Army requirement for rapid generation of digital topographic data to support emerging crisis or contingencies. The primary sensor for this mission is an interferometric synthetic aperture radar (IFSAR) designed at Sandia National Laboratories. This paper will outline the design of the system and its performance, and show some recent flight test results. The RTV IFSAR will meet DTED level III and IV specifications by using a multiple-baseline design and high-accuracy differential and carrier-phase GPS navigation. It includes innovative near-real-time DEM production on-board the aircraft. The system is being flown on a deHavilland DHC-7 Army aircraft.
Date: October 31, 2000
Creator: BURNS,BRYAN L.; EICHEL,PAUL H.; HENSLEY JR.,WILLIAM H. & KIM,THEODORE J.
System: The UNT Digital Library
Soft and hard interactions in p {bar p} collisions at {radical}s = 1800 and 630 GeV (open access)

Soft and hard interactions in p {bar p} collisions at {radical}s = 1800 and 630 GeV

Proton-antiproton events collected with the CDF minimum-bias trigger at {radical}(s) = 1800 and 630 GeV are studied splitting the full event sample in a soft subsample of events with no energy clusters above 1.1 GeV and in the subsample of the remaining events. Detailed and precise analyses of the multiplicity and transverse momentum distributions as well as of the correlation of the average pt and of its dispersion with the multiplicity are performed for the two samples. Comparisons of the results and of their dependence from the center of mass energy show clear differences in their behaviors. The results support important and unexpected scaling properties of the soft sample.
Date: October 31, 2000
Creator: Rimondi, Franco
System: The UNT Digital Library
Measurement of d{sigma}/dy for high mass Drell-Yan e+ e- pairs at CDF (open access)

Measurement of d{sigma}/dy for high mass Drell-Yan e+ e- pairs at CDF

None
Date: October 31, 2000
Creator: Bodek, Atie
System: The UNT Digital Library
Conformational Analysis of the Non-Planar Deformations of Cobalt Porphyrin Complexes in the Cambridge Structural Database (open access)

Conformational Analysis of the Non-Planar Deformations of Cobalt Porphyrin Complexes in the Cambridge Structural Database

None
Date: October 31, 2000
Creator: Cullen, David L; Desai, Lopa V.; Zimmer, Marc & Shelnutt, John A.
System: The UNT Digital Library
PreFPIX2: Core architecture and results (open access)

PreFPIX2: Core architecture and results

None
Date: October 31, 2000
Creator: al., James R. Hoff et
System: The UNT Digital Library
Deformation of the rock mass in the drift scale test (open access)

Deformation of the rock mass in the drift scale test

The United States Department of Energy (DOE) is investigating Yucca Mountain, Nevada, for its feasibility as a potential deep geological repository of high-level nuclear waste. In a deep geological repository, radioactive decay heat released from high-level nuclear waste will heat up the rock mass. Although the following discussion about the thermal-hydrological (TH) process may not be directly relate to the topic of this paper, it provides a bigger picture of the processes in a potential repository. The heat will mobilize pore water in the rock mass by evaporation, or boiling if the thermal load is great enough. The water vapor/steam will flow away from the heat source because of pressure and thermal gradients and the effects of buoyancy force. The vapor/steam will flow along fractures or highly permeable zones and condense into liquid water in the cooler regions. Gravity and the fracture network will control the drainage of the condensed water. Some water may flow back toward the waste package and re-evaporate. This TH process will affect the amount of water that may come into contact with the waste package. Water is the main concern in maintaining the integrity of the waste package and the waste form, and the potential …
Date: October 31, 2000
Creator: Lin, W; Cho, J; Wagoner, J & Wilder, D
System: The UNT Digital Library
Temperature as a diagnostic for the drift scale test (open access)

Temperature as a diagnostic for the drift scale test

The United States Department of Energy (DOE) is investigating Yucca Mountain, Nevada, for its feasibility as a potential deep geological repository of high-level nuclear waste. In a deep geological repository, the radioactive decay heat released from high-level nuclear waste will heat up the rock mass. The heat will mobilize pore water in the rock mass by evaporation, and even boiling, if the thermal load is great enough. The water vapor/steam will flow away from the heat source because of pressure and thermal gradients and the effects of buoyancy force. The vapor/steam may flow along fractures or highly permeable zones and condense into liquid water in the cooler regions. Gravity and fracture network will control the drainage of the condensed water. Some of the water may flow back toward the waste package and reevaporated. This thermal-hydrological (TH) process will affect the amount of water that may come into contact with the waste package. Water is the main concern for the integrity of the waste package and the waste form, and the potential transport of radioactive nuclides. Thermally driven chemical and mechanical processes may affect the TH process. The coupled thermal-hydrological-mechanical-chemical (THMC) processes need to be understood before the performance of a …
Date: October 31, 2000
Creator: Lin, W; Wagoner, J & Ballard, S
System: The UNT Digital Library
An Ultra-High Gradient Plasma Wakefield Booster (open access)

An Ultra-High Gradient Plasma Wakefield Booster

We present a Plasma Wakefield Acceleration (PWFA) scheme that can in principle provide an acceleration gradient above 100 GeV/m, based on a reasonable modification of the existing SLAC beam parameters. We also study a possible up-grade of the Stanford Linear Collider (SLC) to hundreds of GeV center-of-mass energy using such a PWFA as a booster. The emittance degradation of the accelerated beams by the plasma wakefield focus is relatively small due to a uniform transverse distribution of the driving beam and the single stage acceleration.
Date: October 31, 2000
Creator: Chen, P.; Ruth, R.; Cheshkov, S. & Tajima, T.
System: The UNT Digital Library
Thermomechanical characterization of nickel-titanium-copper shape memory alloy films (open access)

Thermomechanical characterization of nickel-titanium-copper shape memory alloy films

In an effort to develop a more extensive model for the thermomechanical behavior of shape memory alloy (SMA) films, a novel characterization method has been developed. This automated test has been tailored to characterize films for use in micro-electromechanical system (MEMS) actuators. The shape memory effect in NiTiCu is seen in the solid-state phase transformation from an easily deformable low-temperature state to a 'shape remembering' high-temperature state. The accurate determination of engineering properties for these films necessitates measurements of both stress and strain in microfabricated test structures over the full range of desired deformation. Our various experimental methods (uniaxial tensile tests, bimorph curvature tests and diaphragm bulge tests) provide recoverable stress and strain data and the stress-strain relations for these films. Tests were performed over a range of temperatures by resistive heating or ambient heating. These measurements provide the results necessary for developing active SMA structural film design models.
Date: October 31, 2000
Creator: Seward, K P; Ramsey, P B & Krulevitch, P
System: The UNT Digital Library