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Structural and electronic properties of carbon nanotube tapers

Description: Article on structural and electronic properties of carbon nanotube tapers, a set of nanostructures comprised of straight tubular sections with decreasing diameters, joined to each other via conical funnels and terminated with a hemispherical cap.
Date: October 29, 2001
Creator: Meunier, Vincent; Buongiorno Nardelli, Marco; Roland, Christopher & Bernholc, Jerry
Partner: UNT College of Arts and Sciences
open access

Promising X-ray fluorescence tests for superconducting tunneljunction detector

Description: Scientists in the Physical Biosciences Division of the Ernest Orlando Berkeley National Laboratory (Berkeley Lab) studying transition metals in proteins with fluorescence-detected L-edge absorption spectroscopy have found the measurements to be extremely challenging. The difficulty is that the metal centers are present in very dilute concentrations so that their weak fluorescence is often obscured by strong background signals carbon and oxygen. To solve this problem, the Berkeley group has been… more
Date: May 15, 2001
Creator: Friedrich, Stephan & Robinson, Arthur L.
Partner: UNT Libraries Government Documents Department
open access

The use of a permanent magnet for water content measurements ofwood chips

Description: The Lawrence Berkeley National Laboratory has developed a device that measures the water content of wood chips, pulp and brown stock for the paper industry. This device employs a permanent magnet as the central part of a NMR measurement system. This report describes the magnet and the NMR measurement system. The results of water content measurements in wood chips in a magnetic field of 0.47 T are presented.
Date: September 20, 2001
Creator: Barale, P. J.; Fong, C. G.; Green, M. A.; Luft, P. A.; McInturff, A. D.; Reimer, J. A. et al.
Partner: UNT Libraries Government Documents Department
open access

The Application of System Dynamics to the Integration of National Laboratory Research and K-12 Education

Description: The Idaho National Engineering and Environmental Laboratory (INEEL) is dedicated to finding solutions to problems related to the environment, energy, economic competitiveness, and national security. In an effort to attract and retain the expertise needed to accomplish these challenges, the INEEL is developing a program of broad educational opportunities that makes continuing education readily available to all laboratory employees, beginning in the K–12 environment and progressing through post-g… more
Date: August 1, 2001
Creator: Mills, James Ignatius & Zounar Harbour, Elda D
Partner: UNT Libraries Government Documents Department
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A monitoring sensor management system for grid environments

Description: Large distributed systems, such as computational grids,require a large amount of monitoring data be collected for a variety oftasks, such as fault detection, performance analysis, performance tuning,performance prediction and scheduling. Ensuring that all necessarymonitoring is turned on and that the data is being collected can be avery tedious and error-prone task. We have developed an agent-basedsystem to automate the execution of monitoring sensors and the collectionof event data.
Date: June 1, 2001
Creator: Tierney, Brian; Crowley, Brian; Gunter, Dan; Lee, Jason & Thompson, Mary
Partner: UNT Libraries Government Documents Department
open access

Limitations of science and adaptive management

Description: Adaptive management consists in patterning human sustenancewithin the constraints of Earth and biological systems whose behavior isinherently uncertain and difficult to control. For successful adaptivemanagement, a mind-set recognizing the limitations of science isneeded.
Date: December 20, 2001
Creator: Narasimhan, T.N.
Partner: UNT Libraries Government Documents Department
open access

Planning for an integrated research experiment

Description: We describe the goals and research program leading to the Heavy Ion Integrated Research Experiment (IRE). We review the basic constraints which lead to a design and give examples of parameters and capabilities of an IRE. We also show design tradeoffs generated by the systems code IBEAM.
Date: March 25, 2001
Creator: Barnard, J. J.; Ahle, L. E.; Bangerter, R. O.; Bieniosek, F. M.; Celata, C. M.; Faltens, A. et al.
Partner: UNT Libraries Government Documents Department
open access

Benefits of microscopy with super resolution

Description: Transmission Electron Microscopy developed from an imagingtool into a quantitative electron beam characterization tool that locallyaccesses structure, chemistry, and bonding in materials with sub Angstromresolution. Experiments utilize coherently and incoherently scatteredelectrons. In this contribution, the interface between gallium nitrideand sapphire as well as thin silicon gate oxides are studied tounderstand underlying physical processes and the strength of thedifferent microscopy techniqu… more
Date: July 9, 2001
Creator: Kisielowski, C.; Principe, E.; Freitag, B. & Hubert, D.
Partner: UNT Libraries Government Documents Department
open access

X-ray Measurements of a Thermo Scientific P385 DD Neutron Generator

Description: Idaho National Laboratory is experimenting with electrical neutron generators, as potential replacements for californium-252 radioisotopic neutron sources in its PINS prompt gamma-ray neutron activation analysis (PGNAA) system for the identification of military chemical warfare agents and explosives. In addition to neutron output, we have recently measured the x-ray output of the Thermo Scientific P385 deuterium-deuterium neutron generator. X-rays are a normal byproduct from a neutron generator… more
Date: August 1, 2001
Creator: Seabury, E. H.; Chichester, D. L.; Caffrey, A. J.; Simpson, J.; Lemchak, M. & Wharton, C. J.
Partner: UNT Libraries Government Documents Department
open access

Phase-Dependent Carrier Processes in Silicon-Based Photovoltaic Materials: Preprint

Description: Presented at the 2001 NCPV Program Review Meeting: Comparative studies of dynamics of photoexcited carriers in range of Si-based materials of interest for PV applications.
Date: October 1, 2001
Creator: Dexheimer, S. L.; Myers, K. E.; Liu, J.; Wang, Q. & Nelson, B. P.
Partner: UNT Libraries Government Documents Department
open access

Thin Film Partnership National Research Teams: Preprint

Description: Presented at the 2001 NCPV Program Review Meeting: The Thin Film Partnership has organized three National Research Teams in CIS, CdTe, and amorphous silicon.
Date: October 1, 2001
Creator: Zweibel, K.
Partner: UNT Libraries Government Documents Department
open access

Performance Summary for the First Solar CdTe 1-kW System: Preprint

Description: Presented at the 2001 NCPV Program Review Meeting: Describes performance of 1-kWac CdTe PV array from First Solar operated at NREL from 6/95 to 14/00. This paper describes the performance of a 1-kW{sub ac} CdTe PV array from First Solar (formerly Solar Cells, Inc.) operated at NREL from June 1995 to November 2000. The PV array operating efficiencies over the 5.5-year period were calculated from 15-minute averages to determine changes in seasonal and annual performance. Performance measurements … more
Date: October 1, 2001
Creator: Marion, B.; del Cueto, J.; McNutt, P. & Rose, D.
Partner: UNT Libraries Government Documents Department
open access

A Germanium-Based, Coded Aperture Imager

Description: We describe a coded-aperture based, gamma-ray imager that uses a unique hybrid germanium detector system. A planar, germanium strip detector, eleven millimeters thick is followed by a coaxial detector. The 19 x 19 strip detector (2 mm pitch) is used to determine the location and energy of low energy events. The location of high energy events are determined from the location of the Compton scatter in the planar detector and the energy is determined from the sum of the coaxial and planar energies… more
Date: October 31, 2001
Creator: Ziock, K P; Madden, N; Hull, E; William, C; Lavietes, T & Cork, C
Partner: UNT Libraries Government Documents Department
open access

Reactive Transport Modeling of Geologic CO{sub 2} Sequestration in Saline Aquifers: The Influence of Intra-Aquifer Shales and the Relative Effectiveness of Structural, Solubility, and Mineral Trapping During Prograde and Retrograde Sequestration

Description: In this study, we address a series of fundamental questions regarding the processes and effectiveness of geologic CO{sub 2} sequestration in saline aquifers. We begin with the broadest: what is the ultimate fate of CO{sub 2} injected into these environments? Once injected, it is immediately subject to two sets of competing processes: migration processes and sequestration processes. In terms of migration, the CO{sub 2} moves by volumetric displacement of formation waters, with which it is largel… more
Date: April 24, 2001
Creator: Johnson, J. W.; Nitao, J. J.; Steefel, C. I. & Knauss, K. G.
Partner: UNT Libraries Government Documents Department
open access

Energy Production and Performance of Polycrystalline Silicon Technology Photovoltaic Modules in the Field: Preprint

Description: Presented at the 2001 NCPV Program Review Meeting: Energy production and performance of polycrystalline silicon technology photovoltaic modules in the field. Six polycrystalline silicon photovoltaic modules--two apiece from three manufacturers--were simultaneously deployed outdoors on the performance and energy ratings testbed at NREL's Outdoor Test Facility (OTF) in June 2000. In situ electrical performance and energy production from these modules obtained under ambient conditions in the field… more
Date: October 1, 2001
Creator: del Cueto, J. A.
Partner: UNT Libraries Government Documents Department
open access

H-Diffusion Mechanism(s) in PECVD Nitride Passivation of Si Solar Cells: Preprint

Description: Presented at the 2001 NCPV Program Review Meeting: Modeled diffusion of H in 2-step Si{sub 3}N{sub 4} passivation process invoking concept of storage of H. H stored during nitridation is redistributed during subsequent anneal. The modeling results agree with this hypothesis, and the conclusions also appear to concur with the observations.
Date: October 1, 2001
Creator: Sopori, B. & Zhang, Y.
Partner: UNT Libraries Government Documents Department
open access

DOE Fundamental and Exploratory Research Program in Photovoltaics: Preprint

Description: Presented at the 2001 NCPV Program Review Meeting: Overview of the Fundamental and Exploratory Research project with the DOE Basic Sciences program and the National Center for Photovoltaics. This paper presents an overview of the Fundamental and Exploratory Research project within the U.S. Department of Energy's National Center for Photovoltaics (NCPV). The idea behind the project is to identify, support, evaluate and coordinate an optimal spectrum of complementary projects that either contribu… more
Date: October 1, 2001
Creator: Matson, R.; McConnell, R. & Eddy, F. P.
Partner: UNT Libraries Government Documents Department
open access

THM Model Validation: Integrated Assessment of Measured and Predicted Behavior

Description: This paper presents results of coupled thermal-hydrological-mechanical (THM) simulations of two field-scale tests that are part of the thermal testing program being conducted by the Yucca Mountain Site Characterization Project. The two tests analyzed are the Drift-Scale Test (DST) which is sited in an alcove of the Exploratory Studies Facility at Yucca Mountain, Nevada, and the Large Block Test (LBT) which is sited at Fran Ridge, near Yucca Mountain, Nevada. Both of these tests were designed to… more
Date: October 10, 2001
Creator: Blair, S C; Carlson, S R; Wagoner, J; Wagner, R & Vogt, T
Partner: UNT Libraries Government Documents Department
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