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The AWM-SIAM Sonia Kovalesvky Lecture - 3 part Lecture Series

Description: The Association for Women in Mathematics (AWM) in cooperation with the Society for Industrial and Applied Mathematics (SIAM) and with funding from the Department of Energy initiated a new lecture series. The purpose of the lecture series is to increase the visibility of women who have made significant contributions in applied or computational mathematics. The AWM-SIAM Sonia Kovalevsky Lecture is presented at the SIAM Annual Meeting which is a national conference. The lecturer is a woman who has… more
Date: June 3, 2003
Creator: Lenhart, Suzanne & Lewis, Jennifer
Partner: UNT Libraries Government Documents Department
open access

Low-level detection and quantification of Plutonium(III, IV, V,and VI) using a liquid core waveguide

Description: Understanding the aqueous chemistry of plutonium, in particular in environmental conditions, is often complicated by plutonium's complex redox chemistry. Because plutonium possesses four oxidation states, all of which can coexist in solution, a reliable method for the identification of these oxidation states is needed. The identification of plutonium oxidation states at low levels in aqueous solution is often accomplished through an indirect determination using series of liquid-liquid extractio… more
Date: June 28, 2003
Creator: Wilson, Richard E.; Hu, Yung-Jin & Nitsche, Heino
Partner: UNT Libraries Government Documents Department
open access

Interfacial behavior of polymer electrolytes

Description: Evidence is presented concerning the effect of surfaces on the segmental motion of PEO-based polymer electrolytes in lithium batteries. For dry systems with no moisture the effect of surfaces of nano-particle fillers is to inhibit the segmental motion and to reduce the lithium ion transport. These effects also occur at the surfaces in composite electrodes that contain considerable quantities of carbon black nano-particles for electronic connection. The problem of reduced polymer mobility is com… more
Date: June 3, 2003
Creator: Kerr, John; Kerr, John B.; Han, Yong Bong; Liu, Gao; Reeder, Craig; Xie, Jiangbing et al.
Partner: UNT Libraries Government Documents Department
open access

Photovoltaic Module Thermal/Wind Performance: Long-Term Monitoring and Model Development for Energy Rating

Description: In order to predict the energy production of photovoltaic (PV) modules, it is necessary to predict the module temperature as a function of ambient temperature, wind speed, wind direction, total irradiance, and relative humidity. This paper presents a mathematical model to predict the module temperature based on the field monitored real data of module temperature, ambient temperature, wind speed, wind direction and relative humidity.
Date: June 1, 2003
Creator: TamizhMani, G.; Ji, L.; Tang, Y.; Petacci, L. & Osterwald, C.
Partner: UNT Libraries Government Documents Department
open access

DESIGN OF SUPERCONDUCTING COMBINED FUNCTION MAGNETS FOR THE 50 GEV PROTON BEAM LINE FOR THE J-PARC NEUTRINO EXPERIMENT.

Description: Superconducting combined function magnets will be utilized for the 50GeV-750kW proton beam line for the J-PARC neutrino experiment and an R and D program has been launched at KEK. The magnet is designed to provide a combined function with a dipole field of 2.59 T and a quadrupole field of 18.7 T/m in a coil aperture of 173.4 mm. A single layer coil is proposed to reduce the fabrication cost and the coil arrangement in the 2-D cross-section results in left-right asymmetry. This paper reports the… more
Date: June 15, 2003
Creator: Wanderer, P. & Al., Et
Partner: UNT Libraries Government Documents Department
open access

Measured and Calculated Losses in a Model Dipole for Gsi's Heavy Ion Synchrotron.

Description: The new heavy ion synchrotron facility proposed by GSI will have two superconducting magnet rings in the same tunnel, with rigidities of 300T{center_dot}m and 10OT{center_dot}m. Fast ramp times are needed. These can cause problems of ac loss and field distortion in the magnets. For the high energy ring, a lm model dipole magnet has been built, based on the RHIC dipole design. This magnet was tested under boiling liquid helium in a vertical dewar. The quench current showed very little dependence… more
Date: June 15, 2003
Creator: Wanderer, P.; Anerella, M.; Ganetis, G.; Ghosh, A. K.; Joshi, P.; Marone, A. et al.
Partner: UNT Libraries Government Documents Department
open access

Effects of Spatial Variations in Packing Fraction of Reactor Physics Parameters in Pebble-Bed Reactors

Description: The well-known spatial variation of packing fraction near the outer boundary of a pebble-bed reactor core is cited. The ramifications of this variation are explored with the MCNP computer code. It is found that the variation has negligible effects on the global reactor physics parameters extracted from the MCNP calculations for use in analysis by diffusion-theory codes, but for local reaction rates the effects of the variation are naturally important. Included is some preliminary work in using … more
Date: June 11, 2003
Creator: Terry, W. K.; Ougouag, A. M.; Rahnema, F. & Mckinley, M. S.
Partner: UNT Libraries Government Documents Department
open access

Correlation of Structural and Electronic Properties with Solar Cell Efficiency for Amorphous Silicon Deposited at Increasing Growth Rates

Description: This paper details the effects of increasing the growth rate of hydrogenated amorphous silicon (a-Si:H), deposited by dc plasma chemical vapor deposition, on the structural and electronic properties of the material in comparison with the performance of solar cells incorporating such layers. The hydrogen content exhibits the strongest correlation with the solar cell efficiency. The defect density measured by two different techniques, correlate poorly but when measured by a third technique, corre… more
Date: June 1, 2003
Creator: Ganguly, G.; Han, D.; Williamson, D. L.; Nelson, B. P. & Cohen, J. D.
Partner: UNT Libraries Government Documents Department
open access

Multivariate Clustering of Large-Scale Scientific Simulation Data

Description: Simulations of complex scientific phenomena involve the execution of massively parallel computer programs. These simulation programs generate large-scale data sets over the spatio-temporal space. Modeling such massive data sets is an essential step in helping scientists discover new information from their computer simulations. In this paper, we present a simple but effective multivariate clustering algorithm for large-scale scientific simulation data sets. Our algorithm utilizes the cosine simi… more
Date: June 13, 2003
Creator: Eliassi-Rad, T & Critchlow, T
Partner: UNT Libraries Government Documents Department
open access

Domain Walls in Random Field Ising Magnets: Wetting

Description: Domain walls in random-field Ising magnets can be investigated in groundstates into which walls are induced by prepared boundary conditions. We outline recent progress, and new results on (domain wall) wetting in random field systems. This is studied in fixed disorder configurations in the presence of an external field, which is varied.
Date: June 12, 2003
Creator: Seppala, E T; Alava, M J & Sillanpaa, I J
Partner: UNT Libraries Government Documents Department
open access

Identification of Wind Turbine Response to Turbulent Inflow Structures: Preprint

Description: The National Renewable Energy Laboratory conducted an experiment to obtain detailed wind measurements and corresponding wind turbine measurements in order to establish a causal relationship between coherent turbulent structures and wind turbine blade fatigue loads. Data were collected for one entire wind season from October 2000 to May 2001. During this period, the wind turbine operated under atmospheric conditions that support the formation of coherent turbulent structures 31% of the time. Usi… more
Date: June 1, 2003
Creator: Hand, M. M.; Kelley, N. D. & Balas, M. J.
Partner: UNT Libraries Government Documents Department
open access

Microsecond Microfluidic Mixing for Investigation of Protein Folding Kinetics

Description: We have developed and characterized a mixer to study the reaction kinetics of protein folding on a microsecond timescale. The mixer uses hydrodynamic focusing of pressure-driven flow in a microfluidic channel to reduce diffusion times as first demonstrated by Knight et al.[1]. Features of the mixer include 1 {micro}s mixing times, sample consumptions of order 1 nl/s, loading sample volumes on the order of microliters, and the ability to manufacture in fused silica for compatibility with most sp… more
Date: June 25, 2003
Creator: Hertzog, D E; Santiago, J G & Bakajin, O
Partner: UNT Libraries Government Documents Department
open access

rSUGRA: Putting Nonuniversal Gaugino Masses on the (W)MAP

Description: In this talk, we investigate the relic density and direct detection prospects of rSUGRA, a simple paradigm for supersymmetry breaking that allows for nonuniversal gaugino masses. We present updated plots reflecting the latest cosmological measurements from WMAP.
Date: June 17, 2003
Creator: Birkedal-Hansen, Andreas
Partner: UNT Libraries Government Documents Department
open access

Modeling a Cold Crucible Induction Heated Melter

Description: FIDAP has been used to simulate melting of radioactive waste glass in a cold crucible induction heated melter. A model has been created that couples the magnetic vector potential (real and imaginary) to a transient startup of the melting process. This magnetic field is coupled to the mass, momentum, and energy equations that vary with time and position as the melt grows. The coupling occurs with the electrical conductivity of the glass as it rises above the melt temperature of the glass and hea… more
Date: June 1, 2003
Creator: Hawkes, Grant L.
Partner: UNT Libraries Government Documents Department
open access

Key differences in the fabrication, irradiation and high temperature accident testing of US and German TRISO-coated particle fuel, and their implications on fuel performance

Description: Historically, the irradiation performance of TRISO-coated gas reactor particle fuel in Germany has been superior to that in the US. German fuel generally has displayed gas release values during irradiation three orders of magnitude lower than US fuel. Thus, we have critically examined the TRISO-coated fuel fabrication processes in the US and Germany and the associated irradiation database with a goal of understanding why the German fuel behaves acceptably, why the US fuel has not faired as well… more
Date: June 1, 2003
Creator: Petti, David Andrew; Buongiorno, Jacopo; Maki, John Thomas & Hobbins, Richard Redfield
Partner: UNT Libraries Government Documents Department
open access

Using the National Environmental Policy Act to Fight Wildland Fires on the Idaho National Engineering and Environmental Laboratory

Description: The decade of the 90s saw an average of 106,000 wildland fires each year, resulting in an average yearly loss of 3.7 million acres across the United States. The total number of acres burned during the past decade exceeded 36 million acres (about 57 thousand square miles). This is an area about the size of the state of Iowa. The impact from wildland fires on federal lands came to the nation’s attention in May of 2000, when the "Cerro Grande" fire near Los Alamos, New Mexico burned 47,650… more
Date: June 1, 2003
Creator: Irving, John S
Partner: UNT Libraries Government Documents Department
open access

Using Addenda in Documented Safety Analysis Reports

Description: This paper discusses the use of addenda to the Radioactive Waste Management Complex (RWMC) Documented Safety Analysis (DSA) located at the Idaho National Engineering and Environmental Laboratory (INEEL). Addenda were prepared for several systems and processes at the facility that lacked adequate descriptive information and hazard analysis in the DSA. They were also prepared for several new activities involving unreviewed safety questions (USQs). Ten addenda to the RWMC DSA have been prepared si… more
Date: June 1, 2003
Creator: Swanson, Douglas S. & Thieme, Michael A.
Partner: UNT Libraries Government Documents Department
open access

Active, Non-Intrusive Inspection Technologies for Homeland Defense

Description: Active, non-intrusive inspection or interrogation technologies have been used for 100 years - with the primary focus being radiographic imaging. During the last 50 years, various active interrogation systems have been investigated and most have revealed many unique and interesting capabilities and advantages that have already benefited the general public. Unfortunately, except for medical and specific industrial applications, these unique capabilities have not been widely adopted, largely due t… more
Date: June 1, 2003
Creator: Jones, James L.
Partner: UNT Libraries Government Documents Department
open access

Gallium Safety in the Laboratory

Description: A university laboratory experiment for the US Department of Energy magnetic fusion research program required a simulant for liquid lithium. The simulant choices were narrowed to liquid gallium and galinstan (Ga-In-Sn) alloy. Safety information on liquid gallium and galinstan were compiled, and the choice was made to use galinstan. A laboratory safety walkthrough was performed in the fall of 2002 to support the galinstan experiment. The experiment has been operating successfully since early 2002. more
Date: June 1, 2003
Creator: Cadwallader, Lee C.
Partner: UNT Libraries Government Documents Department
open access

Morphological, rheological and electrochemical studies ofpoly(ethylene oxide) electrolytes containing fumed silicananoparticles

Description: In this paper, the rheology and crystallization of composite Poly(Ethylene Oxide) (PEO) electrolytes were studied by dynamic mechanical analysis, DSC and polarized light microscopy. The effects of fumed silica nanoparticles on the conductivities of the polymer electrolytes at temperatures above and below their melting point were measured and related to their rheology and crystallization behavior, respectively. The electrolyte/electrode interfacial properties and cycling performances of the comp… more
Date: June 1, 2003
Creator: Xie, Jiangbing; Kerr, John B.; Duan, Robert G. & Han, Yongbong
Partner: UNT Libraries Government Documents Department
open access

Fabrication of Gas-Filled Tungsten-Coated Glass Shells

Description: OAK-B135 Deuterium (D{sub 2}) filled glass shells coated with a high Z element are needed for high energy density (HED) experiments by researchers at Los Alamos National Laboratory. They report here on our initial attempt to produce such shells. Glass shells made using the drop tower technique were coated with gold, palladium or tungsten, or a mixture of two of these elements. It was found that gold and palladium coatings did not stick well to the glass and resulted in poor or delaminated films… more
Date: June 1, 2003
Creator: Nikroo, A.; Baugh, W. & Steinman, D. A.
Partner: UNT Libraries Government Documents Department
open access

Laser plasma interactions in fused silica cavities

Description: The effect of laser energy on formation of a plasma inside a cavity was investigated. The temperature and electron number density of laser-induced plasmas in a fused silica cavity were determined using spectroscopic methods, and compared with laser ablation on a flat surface. Plasma temperature and electron number density during laser ablation in a cavity with aspect ratio of 4 increased faster with irradiance after the laser irradiance reached a threshold of 5 GW/cm{sup 2}. The threshold irrad… more
Date: June 24, 2003
Creator: Zeng, Xianzhong; Mao, Xianglei; Mao, Samuel S.; Yoo, Jong H.; Greif, Ralph & Russo, Richard E.
Partner: UNT Libraries Government Documents Department
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