Understanding Mechanisms of Radiological Contamination (open access)

Understanding Mechanisms of Radiological Contamination

Over the last 50 years, the study of radiological contamination and decontamination has expanded significantly. This paper addresses the mechanisms of radiological contamination that have been reported and then discusses which methods have recently been used during performance testing of several different decontamination technologies. About twenty years ago the Idaho Nuclear Technology Engineering Center (INTEC) at the INL began a search for decontamination processes which could minimize secondary waste. In order to test the effectiveness of these decontamination technologies, a new simulated contamination, termed SIMCON, was developed. SIMCON was designed to replicate the types of contamination found on stainless steel, spent fuel processing equipment. Ten years later, the INL began research into methods for simulating urban contamination resulting from a radiological dispersal device (RDD). This work was sponsored by the Defense Advanced Research Projects Agency (DARPA) and included the initial development an aqueous application of contaminant to substrate. Since 2007, research sponsored by the US Environmental Protection Agency (EPA) has advanced that effort and led to the development of a contamination method that simulates particulate fallout from an Improvised Nuclear Device (IND). The IND method diverges from previous efforts to create tenacious contamination by simulating a reproducible “loose” contamination. Examining …
Date: March 1, 2014
Creator: Demmer, Rick; Drake, John & Ryan James, PhD
System: The UNT Digital Library
The Effect of Heat Treatments and Coatings on the Outgassing Rate of Stainless Steel Chambers (open access)

The Effect of Heat Treatments and Coatings on the Outgassing Rate of Stainless Steel Chambers

The outgassing rates of four nominally identical 304L stainless steel vacuum chambers were measured to determine the effect of chamber coatings and heat treatments. One chamber was coated with titanium nitride (TiN) and one with amorphous silicon (a-Si) immediately following fabrication. One chamber remained uncoated throughout, and the last chamber was first tested without any coating, and then coated with a-Si following a series of heat treatments. The outgassing rate of each chamber was measured at room temperatures between 15 and 30 deg C following bakes at temperatures between 90 and 400 deg C. Measurements for bare steel showed a significant reduction in the outgassing rate by more than a factor of 20 after a 400 deg C heat treatment (3.5 x 10{sup 12} TorrL s{sup -1}cm{sup -2} prior to heat treatment, reduced to 1.7 x 10{ sup -13} TorrL s{sup -1}cm{sup -2} following heat treatment). The chambers that were coated with a-Si showed minimal change in outgassing rates with heat treatment, though an outgassing rate reduced by heat treatments prior to a-Si coating was successfully preserved throughout a series of bakes. The TiN coated chamber exhibited remarkably low outgassing rates, up to four orders of magnitude lower than the …
Date: March 1, 2014
Creator: Mamum, Md Abdullah A.; Elmustafa, Abdelmageed A,; Stutzman, Marcy L.; Adderley, Philip A. & Poelker, Matthew
System: The UNT Digital Library
Pixel Area Variations in Sensors: A Novel Framework for Predicting Pixel Fidelity and Distortion in Flat Field Response (open access)

Pixel Area Variations in Sensors: A Novel Framework for Predicting Pixel Fidelity and Distortion in Flat Field Response

None
Date: March 13, 2014
Creator: Rasmussen, Andrew
System: The UNT Digital Library
Charmonium and Charmonium-Like States with BaBar (open access)

Charmonium and Charmonium-Like States with BaBar

This report describes Charmonium and Charmonium-Like States with BaBar.
Date: March 14, 2014
Creator: Guido, Elisa
System: The UNT Digital Library
Beam Loading by Distributed Injection of Electrons in a Plasma Wakefield Accelerator (open access)

Beam Loading by Distributed Injection of Electrons in a Plasma Wakefield Accelerator

None
Date: March 14, 2014
Creator: Vafaei-Najafabadi, N.; Marsh, K. A.; Clayton, C. E.; An, W.; Mori, W. B.; Joshi, C. et al.
System: The UNT Digital Library
US DOE-EM On-Site Disposal Cell Working Group - Fostering Communication On Performance Assessment Challenges (open access)

US DOE-EM On-Site Disposal Cell Working Group - Fostering Communication On Performance Assessment Challenges

On-site disposal cells are in use and being considered at several U.S. Department of Energy (USDOE) sites as the final disposition for large amounts of waste associated with cleanup of contaminated areas and facilities. These facilities are typically developed with regulatory oversight from States and/or the US Environmental Protection Agency (USEPA) in addition to USDOE. The facilities are developed to meet design standards for disposal of hazardous waste as well as the USDOE performance based standards for disposal of radioactive waste. The involvement of multiple and different regulators for facilities across separate sites has resulted in some differences in expectations for performance assessments and risk assessments (PA/RA) that are developed for the disposal facilities. The USDOE-EM Office of Site Restoration formed a working group to foster improved communication and sharing of information for personnel associated with these Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) disposal cells and work towards more consistent assumptions, as appropriate, for technical and policy considerations related to performance and risk assessments in support of a Record of Decision and Disposal Authorization Statement. The working group holds teleconferences, as needed, focusing on specific topics of interest. The topics addressed to date include an assessment of the …
Date: March 1, 2014
Creator: Seitz, Roger R.; Suttora, Linda C. & Phifer, Mark
System: The UNT Digital Library
Evidence for the decay B0 -> omega omega and search for B0 -> omega phi (open access)

Evidence for the decay B0 -> omega omega and search for B0 -> omega phi

None
Date: March 10, 2014
Creator: Lees, J. P.; Poireau, V.; Tisserand, V.; /Annecy, LAPP; Grauges, E.; /Barcelona U., ECM et al.
System: The UNT Digital Library
Locally Enhanced Conductivity due to the Tetragonal Domain Structure in LaAlO3/SrTiO3 Heterointerfaces (open access)

Locally Enhanced Conductivity due to the Tetragonal Domain Structure in LaAlO3/SrTiO3 Heterointerfaces

None
Date: March 13, 2014
Creator: Kalisky, Beena; Spanton, Eric M.; Noad, Hilary; Kirtley, John R.; Nowack, Katja C.; Bell, Christopher et al.
System: The UNT Digital Library
Transient Spectroscopic Investigations of Intermediates Involved in CO2 Reduction Under Supercritical CO2 Conditions (open access)

Transient Spectroscopic Investigations of Intermediates Involved in CO2 Reduction Under Supercritical CO2 Conditions

N/A
Date: March 16, 2014
Creator: C., Grills D.; Kawanami, H.; Ishizaka, T. & Chatterjee, M.
System: The UNT Digital Library
Observations of Continuum Depression in Warm Dense Matter with X-Ray Thomson scattering (open access)

Observations of Continuum Depression in Warm Dense Matter with X-Ray Thomson scattering

None
Date: March 10, 2014
Creator: Fletcher, L. B.; Kritcher, A. L.; Pak, A.; Ma, T.; Doppner, T.; Fortmann, C. et al.
System: The UNT Digital Library
FEL Oscillator for EUV Lithography (open access)

FEL Oscillator for EUV Lithography

Report on a study to develop radiation sources for extreme ultraviolet lithography (EUVL) by using a free-electron laser (FEL) with a short-period undulator and a relatively small beam energy.
Date: March 6, 2014
Creator: Stupakov, G. & Zolotorev, M. S.
System: The UNT Digital Library
Modified Anti-de-Sitter Metric, Light-Front Quantized QCD, and Conformal Quantum Mechanics (open access)

Modified Anti-de-Sitter Metric, Light-Front Quantized QCD, and Conformal Quantum Mechanics

None
Date: March 3, 2014
Creator: Dosch, Hans Gunter; Brodsky, Stanley J. & de Teramond, Guy F.
System: The UNT Digital Library