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A MOBILE MELT-DILUTE MODULE FOR THE TREATMENT OF ALUMINUM RESEARCH REACTOR SPENT FUEL

Description: A mobile melt-dilute (MMD) module for the treatment of aluminum research reactor spent fuel is being developed jointly by the Savannah River National Laboratory and Argonne National Laboratory. The process uses a closed system approach to retain fission products/gases inside a sealed canister after treatment. The MMD process melts and dilutes spent fuel with depleted uranium to obtain an isotopic content of less than 20 percent. The final ingot is solidified inside the sealed canister and can b… more
Date: November 3, 2004
Creator: ADAMS, THAD
Partner: UNT Libraries Government Documents Department
open access

IRIS Reactor a Suitable Option to Provide Energy and Water Desalination for the Mexican Northwest Region

Description: The Northwest region of Mexico has a deficit of potable water, along this necessity is the region growth, which requires of additional energy capacity. The IRIS reactor offers a very suitable source of energy given its modular size of 300 MWe and it can be coupled with a desalination plant to provide the potable water for human consumption, agriculture and industry. The present paper assess the water and energy requirements for the Northwest region of Mexico and how the deployment of the IRIS r… more
Date: October 3, 2004
Creator: Alonso, G.; Ramirez, R.; Gomez, C. & Viais, J.
Partner: UNT Libraries Government Documents Department
open access

Measurements of the Optical Constants of Scandium in the 50-1300eV Range.

Description: Scandium containing multilayers have been produced with very high reflectivity in the soft x-ray spectrum. Accurate optical constants are required in order to model the multilayer reflectivity. Since there are relatively few measurements of the optical constants of Scandium in the soft x-ray region we have performed measurements over the energy range of 50-1,300 eV. Thin films of Scandium were deposited by ion-assisted magnetron sputtering at Linkoping University and DC Magnetron sputtering at … more
Date: October 3, 2004
Creator: Aquila, A. L.; Salmassi, F.; Gullikson, E. M.; Eriksson, F. & Birch, J.
Partner: UNT Libraries Government Documents Department
open access

Measurement of the beam longitudinal profile in a storage ring bynon-linear laser mixing

Description: We report on the development of a new technique for the measurement of the longitudinal beam profile in storage rings. This technique, which has been successfully demonstrated at the Advanced Light Source, mixes the synchrotron radiation with the light from a mode-locked solid state laser oscillator in a non-linear crystal. The up-converted radiation is then detected with a photomultiplier and processed to extract, store, and display the required information. The available choices of laser repe… more
Date: May 3, 2004
Creator: Beche, J.-F.; Byrd, J.; De Santis, S.; Denes, P.; Placidi, M.; Turner, W. et al.
Partner: UNT Libraries Government Documents Department
open access

Development of an abort gap monitor for high-energy proton rings

Description: The fill pattern in proton synchrotrons usually features an empty gap, longer than the abort kicker raise time, for machine protection. This gap is referred to as the ''abort gap'' and any particles, which may accumulate in it due to injection errors and diffusion between RF buckets, would be lost inside the ring, rather than in the beam dump, during the kicker firing. In large proton rings, due to the high energies involved, it is vital to monitor the build up of charges in the abort gap with … more
Date: May 3, 2004
Creator: Beche, Jean-Francois; Byrd, John; De Santis, Stefano; Denes, Peter; Placidi, Massimo; Turner, William et al.
Partner: UNT Libraries Government Documents Department
open access

Fe XVII Emission from Hot, Collisional Plasmas

Description: The ratios of the Fe XVII 3s {yields} 2p transitions to that of the dominant 3d {yields} 2p transition measured in high-temperature tokamak plasmas are compared to solar and astrophysical observations. Good agreement is found, indicating that the collisional line formation processes active in opacity-free, low-density, high-temperature laboratory plasmas are a good description of those found in astrophysical plasmas.
Date: December 3, 2004
Creator: Beiersdorfer, P.; Bitter, M.; Von Goeler, S. & Hill, K. W.
Partner: UNT Libraries Government Documents Department
open access

The Nuclear Energy Option for the U.S.--How Far Are We from Public Acceptance?

Description: The recent rise of oil and gasoline prices accompanied by reluctant acknowledgement that traditional sources of energy are limited has renewed public interest in renewable energy sources. This perspective on energy is focusing attention on and facilitating acceptance of alternative energy concepts, such as solar, wind, and biomass. The nuclear energy alternative, while clean with potentially abundant fuel supplies and associated with low costs, is burdened with the frequently negative public op… more
Date: October 3, 2004
Creator: Biedscheid, J.A. & Devarakonda, M.
Partner: UNT Libraries Government Documents Department
open access

Edge Localized Mode Dynamics and Transport in the Scrape-Off Layer of the DIII-D Tokamak

Description: High temporal and spatial resolution measurements in the boundary of the DIII-D tokamak show that edge localized modes (ELMs) are produced in the low field side, are poloidally localized and are composed of fast bursts ({approx}20 to 40 {micro}s long) of hot, dense plasma on a background of less dense, colder plasma ({approx}5 x 10{sup 18} m{sup {+-}3}, 50 eV) possibly created by the bursts themselves. The ELMs travel radially in the scrapeoff layer (SOL), starting at the separatrix at {approx}… more
Date: December 3, 2004
Creator: Boedo, J. A.; Rudakov, D. L.; Hollmann, E.; Gray, D. S.; Burrell, K. H.; Moyer, R. A. et al.
Partner: UNT Libraries Government Documents Department
open access

Computer Simulation for Emergency Incident Management

Description: This report describes the findings and recommendations resulting from the Department of Homeland Security (DHS) Incident Management Simulation Workshop held by the DHS Advanced Scientific Computing Program in May 2004. This workshop brought senior representatives of the emergency response and incident-management communities together with modeling and simulation technologists from Department of Energy laboratories. The workshop provided an opportunity for incident responders to describe the natu… more
Date: December 3, 2004
Creator: Brown, D L
Partner: UNT Libraries Government Documents Department
open access

Recent Developments of the IRIS Project of Interest for Latin America

Description: The IRIS (International Reactor Innovative and Secure) reactor design is being developed by an international consortium of 21 organizations from ten countries, including three members from Brazil and one from Mexico. This reflects the interest that Latin America has for a project which addresses the energy needs of the region. Presented here are some of the most recent developments in the IRIS project. The project's highest priority is the current pre-application licensing with the US NRC, whic… more
Date: October 3, 2004
Creator: Carelli, M. D. & Petrovic, B.
Partner: UNT Libraries Government Documents Department
open access

Polarization measurement of Iron L-shell lines on EBIT-I

Description: We report measurements of the line polarization of Ne-like and F-like of iron n=3 to n=2 transitions in the x-ray region. We used the ''two-crystal technique'' developed in previous polarization measurements in our laboratory. Preliminary results from our measurements are presented together with the theoretical calculations using the Flexible Atomic Code (FAC). Our calculations show that contributions from cascades play an important role in the polarization calculations of most of the transitio… more
Date: March 3, 2004
Creator: Chen, H.; Beiersdorfer, P.; Robbins, D.; Smith, A. J. & Gu, M. F.
Partner: UNT Libraries Government Documents Department
open access

U.S. Department of Energy Program of International Technical Cooperation for Research Reactor Utilization

Description: The U.S. Department of Energy, National Nuclear Security Administration (DOE/NNSA) has initiated collaborations with the national nuclear authorities of Egypt, Peru, and Romania for the purpose of advancing the commercial potential and utilization of their respective research reactors. Under its Office of International Safeguards ''Sister Laboratory'' program, DOE/NNSA has undertaken numerous technical collaborations over the past decade intended to promote peaceful applications of nuclear tech… more
Date: October 3, 2004
Creator: Chong, D.; Manning, M.; Ellis, R.; Apt, K.; Flaim, S. & Sylvester, K.
Partner: UNT Libraries Government Documents Department
open access

A cartesian grid embedded boundary method for hyperbolic conservation laws

Description: We present a second-order Godunov algorithm to solve time-dependent hyperbolic systems of conservation laws on irregular domains. Our approach is based on a formally consistent discretization of the conservation laws on a finite-volume grid obtained from intersecting the domain with a Cartesian grid. We address the small-cell stability problem associated with such methods by hybridizing our conservative discretization with a stable, nonconservative discretization at irregular control volumes, a… more
Date: October 3, 2004
Creator: Colella, Phillip; Graves, Daniel T.; Keen, Benjamin J. & Modiano, David
Partner: UNT Libraries Government Documents Department
open access

CHANDRA AND XMM-NEWTON OBSERVATIONS OF RDCS1252.9-2927, A MASSIVE CLUSTER AT z = 1.24

Description: We present deep Chandra and XMM-Newton observations of the galaxy cluster RDCS1252.9-2927, which was selected from the ROSAT Deep Cluster Survey (RDCS) and confirmed by extensive spectroscopy with the VLT at redshift z = 1.237. With the Chandra data, the X-ray emission from the intra-cluster medium is well resolved and traced out to 500 kpc, thus allowing a measurement of the physical properties of the gas with unprecedented accuracy at this redshift. We detect a clear 6.7 keV Iron K line in th… more
Date: March 3, 2004
Creator: Demarco, R.; Ettori, S.; Tozzi, P.; Borgani, S.; Mainieri, V.; Nonino, M. et al.
Partner: UNT Libraries Government Documents Department
open access

Calculation of Np-237 and Am-241 Detector Calibration Constants from First Principles

Description: The Analytical Development Section of Savannah River Technology Center (SRTC) was requested to determine the holdup of enriched uranium in a facility as part of an overall deactivation project of the facility. The facility was used to fabricate enriched uranium fuel assemblies, lithium-aluminum target tubes, neptunium assemblies, and miscellaneous components for the production reactors. The results of the holdup assays are essential for determining compliance with the Waste Acceptance Criteria,… more
Date: May 3, 2004
Creator: Dewberry, R. A.
Partner: UNT Libraries Government Documents Department
open access

Impact of Nuclear Energy Futures on Advanced Fuel Cycle Options

Description: The Nuclear Waste Policy Act requires the Secretary of Energy to inform Congress before 2010 on the need for a second geologic repository for spent nuclear fuel. By that time, the spent fuel discharged from current commercial reactors will exceed the statutory limit of the first repository. There are several approaches to eliminate the need for another repository in this century. This paper presents a high-level analysis of these spent fuel management options in the context of a full range of p… more
Date: October 3, 2004
Creator: Dixon, B. W. & Piet, S. J.
Partner: UNT Libraries Government Documents Department
open access

Mechanisms of Strontium and Uranium Removal From Radioactive Waste Simulant Solutions by the Sorbent Monosodium Titanate

Description: High-Level Radioactive Waste (HLW) is the priority problem for the U.S. Dept. of Energy's Environmental Management Program. Current HLW treatment processes at the Savannah River Site (Aiken, SC) include the use of monosodium titanate (MST, similar to NaTi{sub 2}O{sub 5}xH{sub 2}O) to concentrate radioactive strontium (Sr) and actinides. Mechanistic information about radionuclide uptake will provide us with insight about the reliability of MST treatments. We characterized the morphology of MST a… more
Date: December 3, 2004
Creator: Duff, Martine
Partner: UNT Libraries Government Documents Department
open access

Picosecond x-ray laser photoelectron spectroscopy of room temperature and heated materials

Description: An 84.5 eV Ni-like Pd ion 4d - 4p x-ray laser source generated by the LLNL Compact Multipulse Terawatt (COMET) tabletop system has been used to probe the electronic structure of various metals and semiconductors. In addition to the {approx}4 - 5 ps time resolution, the probe provides the necessary high photon flux (>10{sup 12}/pulse), narrow line width ({Delta}E/E{approx}2 x 10{sup -5}) and coherence for studying valence band and shallow core electronic structure levels in a single shot. We … more
Date: August 3, 2004
Creator: Dunn, J; Nelson, A J; van Buuren, T & Hunter, J R
Partner: UNT Libraries Government Documents Department
open access

Pulse duration measurements of a picosecond laser-pumped 14.7 nm x-ray laser

Description: The temporal dependence of the 14.7 nm Ni-like Pd ion x-ray laser is measured as a function of the laser drive conditions with a fast sub-picosecond x-ray streak camera. The chirped pulse amplification laser beam that pumps the inversion process is varied from 0.5 - 27 ps (FWHM) to determine the effect on the x-ray laser pulse duration. The average x-ray laser pulse duration varies by a relatively small factor of 2.5 times from 3.6 ps to 8.1 ps with traveling wave (TW) irradiation conditions. S… more
Date: August 3, 2004
Creator: Dunn, J; Smith, R F; Shepherd, R; Booth, R; Nilsen, J; Hunter, J R et al.
Partner: UNT Libraries Government Documents Department
open access

An Application of the Coda Methodology for Moment-Rate Spectra Using Broadband Stations in Turkey

Description: A recently developed coda magnitude methodology was applied to selected broadband stations in Turkey for the purpose of testing the coda method in a large, laterally complex region. As found in other, albeit smaller regions, coda envelope amplitude measurements are significantly less variable than distance-corrected direct wave measurements (i.e., L{sub g} and surface waves) by roughly a factor 3-to-4. Despite strong lateral crustal heterogeneity in Turkey, we found that the region could be ade… more
Date: February 3, 2004
Creator: Eken, T; Mayeda, K; Hofstetter, A; Gok, R; Orgulu, G & Turkelli, N
Partner: UNT Libraries Government Documents Department
open access

PROGRESS IN DESIGNING A MUON COOLING RING WITH LITHIUM LENSES.

Description: We discuss particle tracking simulations in a storage ring with lithium lens inserts designed for the six-dimensional phase space cooling of muons by the ionization cooling. The ring design contains one or more lithium lens absorbers for transverse cooling that transmit the beam with very small beta-function values, in addition to liquid-hydrogen wedge-shaped absorbers in dispersive locations for longitudinal cooling. Such a ring could comprise the final component of a cooling system for use in… more
Date: March 3, 2004
Creator: FUKUI,Y. CLINE,D. B. GARREN,A. A. KIRK,H. G.
Partner: UNT Libraries Government Documents Department
open access

Mid infrared observations of Van Maanen 2: no substellar companion.

Description: The results of a comprehensive infrared imaging search for the putative 0.06 M{sub {circle_dot}} astrometric companion to the 4.4 pc white dwarf van Mannen 2 are reported. Adaptive optics images acquired at 3.8 {micro}m reveal a diffraction limited core of 0.09 inch and no direct evidence of a secondary. Models predict that at 5 Gyr, a 50 M{sub J} brown dwarf would be only 1 magnitude fainter than van Maanen 2 at this wavelength and the astrometric analysis suggested a separation of 0.2 inch. I… more
Date: November 3, 2004
Creator: Farihi, J; Becklin, E & Macintosh, B
Partner: UNT Libraries Government Documents Department
open access

Radionuclide Inventory Management at the New 100 MeV Isotope Production Facility at LANL

Description: The Isotope Production Facility (IPF) at Los Alamos is operated on the authorization basis of a radiological facility with an inventory limit of a Category 3 Nuclear Facility. For the commissioning of IPF, a ''dummy'' target stack containing Zn, Nb and Al disks, and a ''prototype'' stack were irradiated with a proton beam. The ''prototype'' stack contained two pressed RbCl disks, encapsulated in stainless steel, and a Ga metal target. Typical ''prototype'' stack beam parameters were 88.9 {micro… more
Date: October 3, 2004
Creator: Fassbender, M. E.; Phillips, D. R.; Nortier, F. M.; Trellue, H. R.; Hamilton, V. T.; Heaton, R. C. et al.
Partner: UNT Libraries Government Documents Department
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