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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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At least 289 records · Page 16
All sourcesNASA NTRSDOE OSTI
DOE OSTI2021

181 Ta - fast neutron evaluation [Slides]

Reliable fast-neutron evaluation can be entirely encapsulated in the reaction model and related input. Ta181 is a particularly relevant case due to extraordinary coverage of various observables by differential experiments that offer much help and relatively little headache. Differences from the similar ENDF/B-VIII evaluation include: more advanced modeling (CC OMP, MSD, MSC, decay schemes), more careful selection of models and parameters, new experimental data, and isomers. Overall, improved agreement with differential data and hints of better performance in integral testing.

73 NUCLEAR PHYSICS AND RADIATION PHYSICS↗
DOE OSTI2022

MARSAME Radiological Release Report for Metal Items from TA 53, Set 20

EPC-ES has evaluated the survey results for metal items from the Los Alamos Neutron Science Center (LANSCE) and found that the metal items described in Table 1 of this report (identified by RP Tracking Numbers) meet the criteria for unrestricted release under DOE Order 458.1 Radiation Protection of the Public and the Environment (DOE 2020) and can be recycled. This conclusion is based on the known history of the metal items and on radiation survey data (see the completed RP-Form-031 LANSCE Metals Clearance Log for each item). None of the items in this report are located within radiological areas. Therefore, the items are considered unencumbered and are not subject to the moratorium suspension on metal recycling from Department of Energy facilities. Additionally, LANL has determined that there is no practical opportunity for internal DOE reuse or recycling of this metal. Process knowledge indicates that these metal items were unlikely to ever be in direct contact with the beam and thus are unlikely to have become activated. Surface contamination measurements (both total and removable) showed either no detectable radioactivity or activity levels within the range of background. All measurements for volumetric contamination were indistinguishable from background based on calculated decision limits. Additionally, all gamma isotopic surveys conducted for defense-in-depth showed no identifiable gamma radiation from beam activation.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2022

Update on 17 O evaluation and fast neutron evaluation for 181 Ta [Slides]

Reliable fast-neutron evaluation can be entirely encapsulated in the reaction model and related input. Ta181 is a particularly relevant case due to extraordinary coverage of various observables by differential experiments that offer much help and relatively little headache. Differences from the similar ENDF/B-VIII evaluation are as follows: more advanced modeling (CC OMP, MSD, MSC, decay schemes), more careful selection of models and parameters, new experimental data, and isomers. Overall, there is improved agreement with differential data and hints of better performance in integral testing.

73 NUCLEAR PHYSICS AND RADIATION PHYSICS↗
DOE OSTI2022

MARSAME Radiological Release Report for Metal Items from TA 53, Set 21

EPC-ES has evaluated the survey results for metal items from the Los Alamos Neutron Science Center (LANSCE) and found that the metal items described in Table 1 of this report (identified by RP Tracking Numbers) meet the criteria for unrestricted release under DOE Order 458.1 Radiation Protection of the Public and the Environment (DOE 2020) and can be recycled. This conclusion is based on the known history of the metal items and on radiation survey data (see the completed RP-Form-031 LANSCE Metals Clearance Log for each item). None of the items in this report are located within radiological areas. Therefore, the items are considered unencumbered and are not subject to the moratorium suspension on metal recycling from Department of Energy facilities. Additionally, LANL has determined that there is no practical opportunity for internal DOE reuse or recycling of this metal.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2021

MARSAME Radiological Release Report for Metal Items from TA 53, Set 18

EPC-ES has evaluated the survey results for metal items from the Los Alamos Neutron Science Center (LANSCE) and found that the metal items described in Table 1 of this report (identified by RP Tracking Numbers) meet the criteria for unrestricted release under DOE Order 458.1 Radiation Protection of the Public and the Environment and can be recycled. This conclusion is based on the known history of the metal items and on radiation survey data (see the completed RP-Form-036 LANSCE Metals Clearance Log for each item). None of the items in this report are located within radiological areas. Therefore, the items are considered unencumbered and are not subject to the moratorium suspension on metal recycling from Department of Energy facilities. Additionally, LANL has determined that there is no practical opportunity for internal DOE reuse or recycling of this metal.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2021

MARSAME Radiological Release Report for Metal Items from TA 53, Set 19

EPC-ES has evaluated the survey results for metal items from the Los Alamos Neutron Science Center (LANSCE) and found that the metal items described in Table 1 of this report (identified by RP Tracking Numbers) meet the criteria for unrestricted release under DOE Order 458.1 Radiation Protection of the Public and the Environment and can be recycled. This conclusion is based on the known history of the metal items and on radiation survey data (see the completed RP-Form-036 LANSCE Metals Clearance Log for each item). None of the items in this report are located within radiological areas. Therefore, the items are considered unencumbered and are not subject to the moratorium suspension on metal recycling from Department of Energy facilities. Additionally, LANL has determined that there is no practical opportunity for internal DOE reuse or recycling of this metal.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2023

Quasi-Differential Neutron Scattering Measurements of 181 Ta and Teflon from 1.5 to 20 MeV [Slides]

This presentation covers motivation for the Experiments Performed. Secondly, it touches on upgrades to the Experimental Apparatus for Measurements. Thirdly, it presents quasi-Differential Experimental Methodology a) Pulse Shape Discrimination b) Validation Measurement of Carbon. The presentation concludes with Preliminary Results and Future Studies.

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND ↗
DOE OSTI2023

Isomers and Dark Matter: 180m Ta and 178m Hf [Slides]

Dark matter has attractive gravitational interactions. It does not interact with light, or has very small electromagnetic coupling. It is stable, or has a lifetime much longer than the age of the Universe. No departure model from the law of gravity explains all data, whereas particle dark matter can.

79 ASTRONOMY AND ASTROPHYSICS↗
DOE OSTI2022

MARSAME Radiological Release Report for Metal Items from TA 53, Set 22

EPC-ES has evaluated the survey results for metal items from the Los Alamos Neutron Science Center (LANSCE) and found that the metal items described in Table 1 of this report (identified by RP Tracking Numbers) meet the criteria for unrestricted release under DOE Order458.1 Radiation Protection of the Public and the Environment (DOE 2020) and can be recycled. This conclusion is based on the known history of the metal items and on radiation survey data (see the completed RP-Form-031 LANSCE Metals Clearance Log [LANL 2021a] for each item). None of the items in this report are located within radiological areas. Therefore, the items are considered unencumbered and are not subject to the moratorium suspension on metal recycling from Department of Energy facilities. Additionally, LANL has determined that there is no practical opportunity for internal DOE reuse or recycling of this metal. Process knowledge indicates that these metal items were unlikely to ever bein direct contact with the beam and thus are unlikely to have become activated. Surface contamination measurements (both total and removable) showed either no detectable radioactivity or activity levels within the range of background. All measurements for volumetric contamination were indistinguishable from background based on calculated decision limits. Additionally, all gamma isotopic surveys conducted for defense-in-depth showed no identifiable gamma radiation from beam activation.

36 MATERIALS SCIENCE↗
DOE OSTI2024

Summary of Stack Tests at TA-16-Bldg 205: Horizontal Duct on WETF Roof

In late 2023 and early 2024, testing was done at the Weapons Engineering Tritium Facility (WETF) rooftop exhaust duct to verify that the stack sample location was in compliance with the ANSI standard for stack sampling, ANSI N13.1-1999. This ANSI standard is called out by the Clean Air Act rules for airborne radionuclide emissions from DOE facilities, 40 CFR 61 Subpart H. This sample location is designated 16020504, indicating Technical Area 16, Building 0205. The rooftop duct formerly discharged to Exhaust Stack 04, but in 2007 it was re-routed to exhaust out Building 0450, Exhaust Stack 05. For continuity, we have kept the 16020504 designation to represent this duct sample location.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2025

Impact of Annealing on the Chemical and Superconducting Properties of Ta Thin Films

Tantalum thin films are annealed to dissolve the surface oxide. The effect of annealing is studied using material characterization tools, XPS and TOF-SIMS, and electrical transport measurements of the annealed films are taken using standard PPMS methods to correlate with the surface chemistry. Annealing dissociates the surface oxide, and the oxygen produced diffuses into the thin film. The introduction of oxygen reduces the quality of the thin film, as shown by the suppression of Tc and a reduction in RRR.

Shinde, Maithilee [IIT, Chicago]↗