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Subcritical Measurements Research Program for Fresh and Spent Materials Test Reactor Fuels

Description: 'A series of subcritical noise measurements were performed on fresh and spent University of Missouri Research Reactor fuel assemblies. These experimental measurements were performed for the purposes of providing benchmark quality data for validating transport theory computer codes and nuclear cross-section data used to perform criticality safety analyses for highly enriched, uranium-aluminum Material Test Reactor fuel assemblies. A mechanical test rig was designed and built to hold up to four f… more
Date: May 13, 1999
Creator: Blanchard, A.
Partner: UNT Libraries Government Documents Department
open access

Application of RF Power to Plasma Flow Drive in Fusion Confinement

Description: Wave induced flows can produce radially sheared velocity profiles that can in turn stabilize drift wave turbulence and improve plasma confinement. A second-order kinetic theory is developed in one-dimensional slab geometry to treat radio frequency (RF)-driven plasma flows. The Vlasov equation is solved to second order in the RF electric field. Moments of the second-order distribution function give time-averaged expressions for the heating rate, the wave kinetic flux, and the RF force exerted on… more
Date: September 13, 1999
Creator: Batchelor, D. B.; Berry, L. A.; Carter, M. D. & Jaeger, E. F.
Partner: UNT Libraries Government Documents Department
open access

Influence of Base Pressure on FeMn Exchange Biased Spin-Valve Films

Description: Spin-valve films of structure NiFeCo/Co/Cu/NiFeCo(Co)/FeMn/Cu were deposited on Si substrates by DC planetary magnetron sputtering techniques. The influence of base pressure, P{sub b}, on spin-valve properties was studied by varying P{sub b} over two decades from 3 x 10{sup -8} to 7 x 10{sup -6} Torr. The GMR ratio show a slight increase with increasing P{sub b} until a large decrease occurs at P{sub b} > 3.3 x 10{sup -6} Torr. Exchange bias field and blocking temperature remain constant in … more
Date: August 13, 1999
Creator: Mao, M.; Cerjan, C.; Law, B.; Grabner, F. & Vaidya, S.
Partner: UNT Libraries Government Documents Department
open access

A JAVA User Interface for the Virtual Human

Description: A human simulation environment, the Virtual Human (VH), is under development at the Oak Ridge National Laboratory (ORNL). Virtual Human connects three-dimensional (3D) anatomical models of the body with dynamic physiological models to investigate a wide range of human biological and physical responses to stimuli. We have utilized the Java programming language to develop a flexible user interface to the VH. The Java prototype interface has been designed to display dynamic results from selected p… more
Date: October 13, 1999
Creator: Easterly, C. E.; Strickler, D. J.; Tolliver, J. S. & Ward, R. C.
Partner: UNT Libraries Government Documents Department
open access

Accelerated Life Testing and Service Lifetime Prediction for PV Technologies in the Twenty-First Century

Description: The purposes of this paper are to (1) discuss the necessity for conducting accelerated life testing (ALT) in the early stages of developing new photovoltaic (PV) technologies, (2) elucidate the crucial importance for combining ALT with real-time testing (RTT) in terrestrial environments for promising PV technologies for the 21st century, and (3) outline the essential steps for making a service lifetime prediction (SLP) for any PV technology. The specific objectives are to (a) illustrate the ess… more
Date: July 13, 1999
Creator: Czanderna, A. W. & Jorgensen, G. J.
Partner: UNT Libraries Government Documents Department
open access

InSitu X-Ray Diffraction Studies on Lithium-Ion Battery Cathodes

Description: LiNi{sub 0.8}Co{sub 0.2}O{sub 2} and LiNiO{sub 2} have been characterized in-situ XRD. LiNi{sub 0.8}Co{sub 0.2}O{sub 2} does not undergo a monoclinic phase transformation but remains a hexagonal lattice throughout the entire charging cycle. It is hypothesized that Co-doping may help stabilize the hexagonal structure.
Date: July 13, 1999
Creator: Doughty, Daniel H.; Ingersoll, David & Rodriguez, Mark A.
Partner: UNT Libraries Government Documents Department
open access

InSitu X-Ray Diffraction Studies on Lithium-Ion Battery Cathodes

Description: In this paper numerical simulations of Mach 10 air flow over a hollow cylinder flare are presented in comparison with recent experimental results. The numerical study is performed using a Direct Simulation Monte Carlo code and the experimental results were obtained in the ONERA R5Ch wind tunnel. The flow phenomena involved include shock wave boundary layer interaction in hypersonic laminar flow. An analysis of the requirements on the grid resolution, number of particle simulators and run time i… more
Date: July 13, 1999
Creator: Doughty, Daniel H.; Ingersoll, David & Rodriguez, Mark A.
Partner: UNT Libraries Government Documents Department
open access

Developments on the Toroid Ion Trap Analyzer

Description: Investigations into several areas of research have been undertaken to address the performance limitations of the toroid analyzer. The Simion 3D6 (2) ion optics simulation program was used to determine whether the potential well minimum of the toroid trapping field is in the physical center of the trap electrode structure. The results (Figures 1) indicate that the minimum of the potential well is shifted towards the inner ring electrode by an amount approximately equal to 10% of the r0 dimension… more
Date: June 13, 1999
Creator: Lammert, S.A.; Thompson, C.V. & Wise, M.B.
Partner: UNT Libraries Government Documents Department
open access

Certifying the Waste Isolation Pilot Plant: Lessons Learned from the WIPP Experience

Description: In May 1998, the US Environmental Protection Agency (EPA) certified the US Department of Energy's (DOE) Waste Isolation Pilot Plant (WIPP) as being in compliance with applicable long-term regulations governing the permanent disposal of spent nuclear fuel, high-level, and transuranic radioactive wastes. The WIPP is the first deep geologic repository in the US to have successfully demonstrated regulatory compliance with long-term radioactive waste disposal requirements. The first disposal of TRU … more
Date: July 13, 1999
Creator: Anderson, D.R.; Chu, Margaret S.Y.; Froehlich, Gary K.; Howard, Bryan A.; Howarth, Susan M.; Larson, Kurt W. et al.
Partner: UNT Libraries Government Documents Department
open access

Higgs searches in run 2 at the Tevatron

Description: In Run 2 at the Tevatron, the upgraded CDF and D0 experiments will have greatly improved sensitivity in the search for the Higgs bosons of the Standard Model and minimal supersymmetry. In the past year the Higgs Working Group of the Tevatron Run 2 SUSY/Higgs Workshop has estimated the discovery and exclusion reach for the Higgs, combining all possible search channels and utilizing all the upgraded features of both detectors. The results give strong motivation to continue the next run of the Tev… more
Date: July 13, 1999
Creator: Conway, John S.
Partner: UNT Libraries Government Documents Department
open access

Automated Acquisition and Analysis of Digital Radiographic Images

Description: 'Engineers at the Savannah River Technology Center have designed, built, and installed a fully automated small field-of-view, lens-coupled, digital radiography imaging system. The system is installed in one of the Savannah River Site''s production facilities to be used for the evaluation of production components. Custom software routines developed for the system automatically acquire, enhance, and diagnostically evaluate critical geometric features of various components that have been captured … more
Date: May 13, 1999
Creator: Poland, R.
Partner: UNT Libraries Government Documents Department
open access

Beam dynamics studies for heavy ion fusion drivers

Description: No Description Available.
Date: April 13, 1999
Creator: Barnard, J.; Celata, C.; Craig, G.; Dehoon, M.; Faltens, A.; Friedman, A. et al.
Partner: UNT Libraries Government Documents Department
open access

The temperature of formation of carbonate in Martian meteorite ALH84001: constraints from cation diffusion

Description: An important test of the hypothesis that Martian meteorite ALH84001 contains fossil remnants of an ancient Martian biota is the thermal history of the carbonate rosettes associated with the proposed biomarkers. If carbonates formed at temperatures over {approximately} 110 C (the limit for terrestrial life), it is unlikely that these minerals are associated with a terrestrial-like biota.
Date: August 13, 1999
Creator: Hutcheon, I D; Kent, A; Phinney, D L & Ryerson, F J
Partner: UNT Libraries Government Documents Department
open access

Radiological Assessment System for Consequence Analysis (RASCAL) Version 3.0

Description: The Radiological Assessment System for Consequence AnaLysis, Version 3.0 (RASCAL 3.0) is the U.S. Nuclear Regulatory Commission�s (NRC) main computational tool for use during radiological emergencies. RASCAL estimates doses from radiological accidents for comparison with Protective Action Guides and acute health effects thresholds. It includes six computational tools: ST-Dose, FM-Dose, Decay, BackCalc, UF6Plume, and MetProc. ST-Dose computes time-dependent nuclide release rates, atmospheric tra… more
Date: September 13, 1999
Creator: Athey, G. F.; Fosmire, C.; Mohseni, A.; Ramsdell, J. V. Jr. & Sjoreen, A.
Partner: UNT Libraries Government Documents Department
open access

Detection of Depleted Uranium in Soil Using Portable Hand-Held Instruments

Description: The Measurement Applications and Development Group at the Oak Ridge National Laboratory (ORNL) has collected and analyzed data with the purpose of evaluating the in-situ detection capabilities of common hand-held detectors for depleted uranium ({sup 238}U) in soil. Measurements were collected with one each of the following detectors: a FIDLER operated in a gross (full spectrum) mode, a FIDLER operated in a spectrum specific (windowed) mode, a 1.25'' x 1.5'' cylindrical NaI detector operated wit… more
Date: November 13, 1999
Creator: Coleman, R.L.
Partner: UNT Libraries Government Documents Department
open access

Modeling the post-yield flow behavior after neutron and electron irradiation of steels and iron-base alloys.

Description: Irradiation hardening is an issue of practical importance as it relates to the remanent life and the nature of failure of reactor components exposed to displacement-producing radiation. For example, irradiation-induced yield strength increases in pressure vessel steels are directly related to increases in the ductile-to-brittle-transition-temperature of these materials. Other issues associated with hardening, such as reductions in ductility, toughness and fatigue life of structural steels are a… more
Date: January 13, 1999
Creator: Dimelfi, R. J.
Partner: UNT Libraries Government Documents Department
open access

HIGH RESOLUTION PHOTOEMISSION STUDIES OF COMPLEX MATERIALS.

Description: Recent instrumentation developments in photoemission are providing new insights into the physics of complex materials. With increased energy and momentum resolution, it has become possible to examine in detail different contributions to the self-energy or inverse lifetime of the photohole created in the photoexcitation process, Employing momentum distribution and energy distribution curves, a detailed study of the optimally doped cuprate, Bi{sub 2}Sr{sub 2}CaCu{sub 2}O{sub g+{delta}}, shows tha… more
Date: October 13, 1999
Creator: JOHNSON,P.D.
Partner: UNT Libraries Government Documents Department
open access

A microkernel design for component-based parallel numerical software systems.

Description: What is the minimal software infrastructure and what type of conventions are needed to simplify development of sophisticated parallel numerical application codes using a variety of software components that are not necessarily available as source code? We propose an opaque object-based model where the objects are dynamically loadable from the file system or network. The microkernel required to manage such a system needs to include, at most: (1) a few basic services, namely--a mechanism for loadi… more
Date: January 13, 1999
Creator: Balay, S.
Partner: UNT Libraries Government Documents Department
open access

Organization and management of the plant safety evaluation of the VVER-440/230 units at Novovoronezh.

Description: As part of the Soviet-Designed Reactor Safety (SDRS) element of the International Nuclear Safety Program (INSP), the US Department of Energy (US DOE) is funding a plant safety evaluation (PSE) project for the Novovoronezh Nuclear Power Plant (NvNPP). The Novovoronezh PSE Project is a multi-faceted project with participants from sixteen different international organizations from five different countries scattered across eleven time zones. The purpose of this project is to provide a thorough Prob… more
Date: May 13, 1999
Creator: Afshar, C. M.; Pizzica, P.; Puglia, W. J. & Rozin, V.
Partner: UNT Libraries Government Documents Department
open access

Mechanistic Feature-Scale Profile Simulation of SiO2LPCVD by TEOS Pyrolysis

Description: Simulation of chemical vapor deposition (CVD) in submicron features typical of semiconductor devices has been facilitated by extending the EVOLVE thin film etch and deposition simulation code to use thermal reaction mechanisms expressed in the Chemkin format. This allows consistent coupling between EVOLVE and reactor simulation codes that use Chemkin. In an application of a reactor-scale simulation code providing surface fluxes to a feature-scale simulation code, a proposed reaction mechanism f… more
Date: September 13, 1999
Creator: CALE, TIMOTHY S.; LABUN, ANDREW H. & MOFFAT, HARRY K.
Partner: UNT Libraries Government Documents Department
open access

State-of-the-Art developments in accelerator controls at the APS.

Description: The performance requirements of the Advanced Photon Source (APS) challenge the control system in a number of areas. This paper will review a few applications of advanced technology in the control and monitoring of the APS. The application of digital signal processors (DSPs) and techniques will be discussed, both from the perspective of a large distributed multiprocessor system and from that of embedded systems. In particular, two embedded applications will be highlighted, a beam position monito… more
Date: April 13, 1999
Creator: Lenkszus, F.
Partner: UNT Libraries Government Documents Department
open access

TEWI Analysis: Its Utility, Its Shortcomings, and Its Results

Description: The past decade has been a challenging time for the refrigeration and air conditioning industry worldwide. Provisions of the Montreal Protocol and its amendments require the phaseout of chlorofluorocarbon (CFC) and hydrochlorofluorocarbon (HCFC) compounds that have been used extensively as insulating foam blowing agents and refrigerants in refrigeration systems, heat pumps, and air conditioners. In response, hydrofluorocarbon (HFC) compounds were proposed, developed, and are starting to be used… more
Date: September 13, 1999
Creator: Baxter, V.D.; Fischer, S.K. & Sand, J.R.
Partner: UNT Libraries Government Documents Department
open access

B-Physics prospects at CDF

Description: Between 1992 to 1996, the CDF experiment has collected a data sample of 110 pb{sup -1} of p{bar p} collisions at {radical}s = 1.8 TeV at the Fermilab Tevatron. In the year 2001 the Tevatron will commence p{bar p} collisions again at {radical}s = 2.0 TeV delivering an integrated luminosity of 1 fb{sup -1} per year. In the mean time the CDF detector will have undergone substantial upgrades which will allow for a rich B physics program with unique capabilities. In this paper we discuss the B physi… more
Date: December 13, 1999
Creator: Papadimitriou, Vaia
Partner: UNT Libraries Government Documents Department
open access

Residual Stress Predictions in Polycrystalline Alumina

Description: Microstructure-level residual stresses arise in polycrystalline ceramics during processing as a result of thermal expansion anisotropy and crystallographic disorientation across the grain boundaries. Depending upon the grain size, the magnitude of these stresses can be sufficiently high to cause spontaneous microcracking during the processing of these materials. They are also likely to affect where cracks initiate and propagate under macroscopic loading. The magnitudes of residual stresses in u… more
Date: December 13, 1999
Creator: VEDULA,VENKATA R.; GLASS,S. JILL; SAYLOR,DAVID M.; ROHRER,GREGORY S.; CARTER,W. CRAIG & LANGER,STEPHEN A.
Partner: UNT Libraries Government Documents Department
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