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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 793 records · Page 44
All sourcesNASA NTRSDOE OSTI
DOE OSTI2025

Improved interfacial li-ion transport in composite polymer electrolytes via surface modification of LLZO

Composite polymer electrolytes that incorporate ceramic fillers in a polymer matrix offer mechanical strength and flexibility as solid electrolytes for lithium metal batteries. However, fast Li + transport between polymer and Li + -conductive filler phases is not a simple achievement due to high barriers for Li + exchange across the interphase. This study demonstrates how modification of Li 7 La 3 Zr 2 O 12 (LLZO) nanofiller surfaces with silane chemistries influences Li + transport at local and global electrolyte scales. Anhydrous reactions covalently link amine-functionalized silanes [(3-aminopropyl)triethoxysilane (APTES)] to LLZO nanoparticles, which protects LLZO in air. APTES functionalization lowers the poly (ethylene oxide) (PEO)-LLZO interphase resistance to half that of unmodified LLZO and increases effective Li + transference number, while insulating Al 2 O 3 completely blocks ion exchange and lowers transference number and conductivity in PEO-lithium bis(trifluoromethanesulfonyl)imide (LiTFSI)-LLZO composites. Modeling an inner resistive interphase between LLZO and PEO surrounded by an outer conductive interphase explains non-linear conductivity trends. Solid-state 7 Li & 6 Li nuclear magnetic resonance shows Li + only exchanges between PEO-LiTFSI and some LLZO interphase, with no appreciable Li + transport through bulk LLZO. Surface functionalization is a promising path toward lowering the polymer-ceramic interphase resistance. This work demonstrates that local changes in Li + transport affect macroscopic performance, highlighting the intricate relationships between all interfaces in inherently heterogeneous composite polymer electrolytes.

25 ENERGY STORAGE↗
DOE OSTI2013

Recommendations and Justifications for Modifications To Downgrade Use Restrictions Established under the U.S. Department of Energy, National Nuclear Security Administration Nevada Field Office Federal Facility Agreement and Consent Order (Rev. 1)

This document is part of an effort to reevaluate 37 FFACO and Administrative URs against the current Soils Risk-Based Corrective Action Evaluation Process. After reviewing 37 existing FFACO and Administrative URs, 11 URs addressed in this document have sufficient information to determine that these current URs may be downgraded to Administrative URs based on the RBCA criteria. This document presents recommendations on modifications to existing URs that will be consistent with the RBCA criteria.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2015

Response to Notice of Disapproval TA-63 Transuranic Waste Facility Permit Modification Request, Rev. 2, Los Alamos National Laboratory

This document responds to the August 30, 2012, New Mexico Environment Department- Hazardous Waste Bureau (NMED-HWB) Disapproval notice referenced above. The notice was issued for the Permit Modification Request for Technical Area 63, Transuranic Waste Facility, Hazardous Waste Container Storage Unit (PMR), Revision 2.0, submitted to NMED-HWB on July 13, 2012, by the United States Department of Energy (DOE) and Los Alamos National Security, LLC, collectively the Permittees. The Permittees are seeking to modify the Hazardous Waste Facility Permit (Permit) for Los Alamos National Laboratory (LANL) for approval of the construction of the Transuranic Waste Facility (TWF) at Technical Area 63 (TA-63) and permission to store hazardous waste there. This response may contain information regarding the management of radioactive materials, including source, special nuclear, and byproduct material. Information on radioactive materials and radionuclides, including the results of sampling and analysis of radioactive constituents, is voluntarily provided to NMED-HWB in accordance with DOE policy.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2017

Modification of the SAS4A Safety Analysis Code for Integration with the ADAPT Discrete Dynamic Event Tree Framework.

It is difficult to assess the consequences of a transient in a sodium-cooled fast reactor (SFR) using traditional probabilistic risk assessment (PRA) methods, as numerous safety-related sys- tems have passive characteristics. Often there is significant dependence on the value of con- tinuous stochastic parameters rather than binary success/failure determinations. One form of dynamic PRA uses a system simulator to represent the progression of a transient, tracking events through time in a discrete dynamic event tree (DDET). In order to function in a DDET environment, a simulator must have characteristics that make it amenable to changing physical parameters midway through the analysis. The SAS4A SFR system analysis code did not have these characteristics as received. This report describes the code modifications made to allow dynamic operation as well as the linking to a Sandia DDET driver code. A test case is briefly described to demonstrate the utility of the changes.

98 NUCLEAR DISARMAMENT, SAFEGUARDS, AND PHYSICAL P↗
DOE OSTI2017

Brazil-USA Collaborative Research: Modifications by Anthropogenic Pollution of the Natural Atmospheric Chemistry and Particle Microphysics of the Tropical Rain Forest During the GoAmazon Intensive Operating Periods (IOPs)

Manaus, a city of nearly two million people, represents an isolated urban area having a distinct urban pollution plume within the otherwise pristine Amazon Basin. The plume has high concentrations of oxides of nitrogen and sulfur, carbon monoxide, particle concentrations, and soot, among other pollutants. Critically, the distinct plume in the setting of the surrounding tropical rain forest serves as a natural laboratory to allow direct comparisons between periods of pollution influence to those of pristine conditions. The funded activity of this report is related to the Brazil-USA collaborative project during the two Intensive Operating Periods (wet season, 1 Feb - 31 Mar 2014; dry season, 15 Aug - 15 Oct 2014) of GoAmazon2014/5. The project addresses key science questions regarding the modification of the natural atmospheric chemistry and particle microphysics of the forest by present and future anthropogenic pollution. The first objective of the project was to understand and quantify the interactions of biogenic and anthropogenic emissions with respect to the production of secondary organic material. In clean conditions in the Amazon basin, secondary organic material dominates the diameter distribution of the submicron particles. How and why is the diameter distribution shifted by pollution? The second objective followed from the first in that, although the diameter distribution is dominated by secondary organic material, the actual source of new particle production remains uncertain (i.e., the number concentration). The second objective was to test the hypothesis that new particles under natural conditions are produced as a result of evaporation of primary particles emitted by fungal spores as well as to investigate any shifts in this mechanism under pollution conditions, e.g., in consequence to the high concentrations of SO 2 in the pollution plume. Combined, the number-diameter distribution is the key connection to upscaling to the effects of aerosol particles on clouds and climate. Understanding this upscaling under clean and pollution conditions, including differences, was the third objective.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2017

Atmospheric release model for the E-area low-level waste facility: Updates and modifications

The atmospheric release model (ARM) utilizes GoldSim® Monte Carlo simulation software (GTG, 2017) to evaluate the flux of gaseous radionuclides as they volatilize from E-Area disposal facility waste zones, diffuse into the air-filled soil pores surrounding the waste, and emanate at the land surface. This report documents the updates and modifications to the ARM for the next planned E-Area PA considering recommendations from the 2015 PA strategic planning team outlined by Butcher and Phifer.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2017

Collaborative Research: Atmospheric Pressure Plasma-Biomaterial Surface Interactions - Bridging Understanding of APP Sources to Rational Modification of Biomolecules

The overriding objective of this work is to bridge the gap between understanding of atmospheric pressure plasma (APP) sources and predictive chemical modifications of biomolecules. A key aspect of this problem is to understand what oxidizing species are created in water adjacent to APP jets that would ultimately affect aqueous biomolecules. We report the production of highly oxidative species in solutions exposed to a self-pulsed corona discharge in air. We examine how the properties of the target solution (pH, conductivity) and the discharge power affect the discharge stability and the production of H2O2. Indigo carmine, a common organic dye, is used as an indicator of oxidative strength and in particular, hydroxyl radical (OH•) production. The observed rate of indigo oxidation in contact with the discharge far exceeds that predicted from reactions based on concentrations of species measured in the bulk solution. The generation of H2O2 and the oxidation of indigo carmine indicate a high concentration of highly oxidizing species such as OH• at the plasma-liquid interface. These results indicate that reactions at the air plasma-liquid interface play a dominant role in species oxidation during direct non-equilibrium atmospheric pressure plasma (NE-APP) treatment.

70 PLASMA PHYSICS AND FUSION TECHNOLOGY↗
DOE OSTI2017

Brazil-USA Collaborative Research: Modifications by Anthropogenic Pollution of the Natural Atmospheric Chemistry and Particle Microphysics of the Tropical Rain Forest During the GoAmazon Intensive Operating Periods (IOPs)

Manaus, a city of nearly two million people, represents an isolated urban area having a distinct urban pollution plume within the otherwise pristine Amazon Basin. The plume has high concentrations of oxides of nitrogen and sulfur, carbon monoxide, particle concentrations, and soot, among other pollutants. Critically, the distinct plume in the setting of the surrounding tropical rain forest serves as a natural laboratory to allow direct comparisons between periods of pollution influence to those of pristine conditions. The funded activity of this report is related to the Brazil-USA collaborative project during the two Intensive Operating Periods (wet season, 1 Feb - 31 Mar 2014; dry season, 15 Aug - 15 Oct 2014) of GoAmazon2014/5. The project addresses key science questions regarding the modification of the natural atmospheric chemistry and particle microphysics of the forest by present and future anthropogenic pollution.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2018

Fundamental Studies of Irradiation-Induced Modifications in Microstructural Evolution and Mechanical Properties of Advanced Alloys

This final technical report summarizes the research performed during October 2014 and December 2017, with a focus on investigating the radiation-induced microstructural and mechanical property modifications in optimized advanced alloys for sodium-cooled fast reactor (SFR) structural applications. To accomplish these objectives, the radiation responses of several different advanced alloys, including austenitic steel Alloy 709 (A709) and 316H, and ferritic/ martensitic Fe–9Cr steels T91 and G92, were investigated using a combination of microstructure characterizations and nanoindentation measurements. Different types of irradiation, including ex situ bulk ion irradiation and in situ transmission electron microscopy (TEM) ion irradiation, were employed in this study. Radiation-induced dislocations, precipitates, and voids were characterized by TEM. Scanning transmission electron microscopy with energy dispersive X-ray spectroscopy (STEM-EDS) and/or atom probe tomography (APT) were used to study radiation-induced segregation and precipitation. Nanoindentation was used for hardness measurements to study irradiation hardening. Austenitic A709 and 316H was bulk-irradiated by 3.5 MeV Fe ++ ions to up to 150 peak dpa at 400, 500, and 600°. Compared to neutron-irradiated stainless steel (SS) 316, the Frank loop density of ion-irradiated A709 shows similar dose dependence at 400°, but very different temperature dependence. Due to the noticeable difference in the initial microstructure of A709 and 316H, no systematic comparison on the Frank loops in A709 vs 316H was made. It would be helpful that future ion irradiation study on 316 stainless steel could be conducted to directly compare the temperature dependence of Frank loop density in ion-irradiated 316 SS with that in neutron-irradiated 316 SS. In addition, future neutron irradiation on A709 at 400–600° at relative high dose (≥10 dpa) can be carried out to compare with ion-irradiated A709. The radiation-induced segregation (RIS) of Ni and Si was observed in both A709 and 316H in all irradiated conditions and was found at various sinks: line dislocations, dislocation loops, void surfaces, carbide-matrix interfaces, etc. Radiation also induced the formation of Ni,Si-rich precipitates. As suggested in a previous study on neutron-irradiated 316 stainless steel, one possible consequence of the significant RIS of Si is that the enrichment at defect sinks depletes the silicon in the matrix, which can lead to enhanced void nucleation rate. The enrichment of Ni and Si is accompanied by the depletion of Cr at defect sinks, which could also affect the corrosion resistance. Radiation-induced change in the orientation relationship of pre-existing MX precipitates was observed at 600°. It is believed that this change is associated with the network dislocations formed under irradiation. The underlying mechanism is still not well understood. This change could be a positive indication that the MX precipitates can survive high density network dislocations. It would be helpful if neutron irradiation at similar dose conditions could be carried out to verify that this effect is not unique for ion irradiation. Intragranular Cr-rich carbides with a core-shell structure, i.e. Cr-rich carbide core and Ni,Si-rich shell was found at 500° and 600° in the highest dose (150 peak dpa) specimens. Coarse voids (30 nm in diameter) were only commonly found at 500° in the 50 and 150 peak dpa specimens in regions less than 750 nm in depth. The highest swelling for A709 irradiated to 50 and 150 peak dpa at 500° is about 0.44% and 0.37%, respectively. Due to the choice of 100 degree temperature intervals, this study did not attempt to precisely identify peak void swelling conditions, merely the range of irradiation temperatures where this could be a concern. It is known high-dose ion irradiation can significantly suppress void nucleation. Future neutron irradiation in the 500–600° range (without considering the temperature shift) is needed to determine the onset of accelerated void swelling (possibly at lower dose).

36 MATERIALS SCIENCE↗
DOE OSTI2018

HEMP Modification from Secondary Electron Inertia

We describe a modification to the standard analysis of high frequency electromagnetic pulse (HEMP) that treats the inertia of the secondary electrons. We calculate the radiating HEMP field for an instantaneous gamma source in an idealized geometry with and without inertia. Inertia makes a significant correction to the signal if $\mathcal{V_{en}T_{P}}$ < ~0.1 where $\mathcal{V_{en}}$ is the electron-neutral collision frequency and $\mathcal{T_{P}}$ is the time when the peak radiating HEMP field is reached in the collisionless limit.

58 GEOSCIENCES↗
DOE OSTI2018

Building 1090 Modifications Lessons Learned

The purpose of this document is to capture and disseminate lessons learned from the Sandia National Laboratories (SNL) Building 1090 modification project that took place from 2013 to 2018. The following sections summarize the drivers, issues encountered and lessons learned at each phase in the project.

99 GENERAL AND MISCELLANEOUS↗
DOE OSTI2018

Modifications to MELCOR 1.8.6 for modeling Accident Tolerant Fuel in Boiling Water Reactors

This work describes further modifications made to a previously implemented User-Defined Generalized Coating (UDGC) model in MELCOR 1.8.6. The UDGC version of the code allows for the modeling of cladding and canister materials other than Zircaloy (without overwriting Zircaloy properties) as well as coated Zircaloy cladding and canisters, with the thermophysical and oxidation properties of the clad or coating material specified by the user. Specific changes outlined in this report are the extension of the UDGC models to BWR canisters, and generalization of the oxidation model for all UDGC components to accommodate different oxidation rate correlations in two different temperature ranges. User input requirements are specified and an example case is described that illustrates the potential impact of model assumptions.

22 GENERAL STUDIES OF NUCLEAR REACTORS↗
DOE OSTI2020

Radiation-Induced Modifications in Copper Oxide Growth

Radiation-induced effects and their influence on oxidation processes were evaluated for their use as a forensic tool for special nuclear material (SNM). A beam of 10 MeV Au³⁺ ions was used to mimic the accumulation of microstructural damage from self-irradiation through the decay of radionuclides. Several copper samples were irradiated as suitable surrogate materials at 200 °C with a flux of 1x10¹² ions/cm·s to damage levels of 5, 10, and 15 displacements per atom (dpa). This corresponds to about 50, 100, and 150 years, respectively, of accumulated α-decay damage in a PuGa alloy assuming a damage rate of 0.1 dpa/year. After irradiation, all samples were exposed to an accelerated aging process induced by thermal treatment at 350 °C for 1 hour in air. This resulted in the growth of a mixed oxide layer (Cu₂O and CuO) which was characterized in detail using several complementary analytical techniques: Scanning Electron Microscopy, Raman spectroscopy, Synchrotron X-ray diffraction (transmission mode), and Grazing Incidence X-ray diffraction. The oxide layer growth of irradiated Cu at 350°C is distinctly modified as a result of the ion irradiation. Most notably, the growth of the CuO phase is suppressed with increasing radiation damage on the Cu substrate, and structural changes occurred in the Cu₂O phase. These results indicate that damage from self-irradiation over time can cause quantifiable modifications in the oxidation process of metals that could be harnessed for their use as a novel forensic tool.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Options for Future Fuel/Basket Modifications for DPC Disposition

Deliverable Description: Identify and evaluate options for fuel and basket modifications, for dual-purpose canisters (DPCs) to be loaded in the future, that would substantially reduce the probability of post closure criticality after waste package breach and flooding with ground water. Planned work in FY20 will examine the feasibility of criticality control features, particularly neutron absorbing inserts or replacement channels for boiling water reactor (BWR) fuel assemblies. The expected outcome is additional engineering information that can be used to guide the R&D program, and to support future stakeholder interactions. This document will be incorporated into planned deliverable DPC Disposal Concepts of Operation (M3 SF-20SNO10305052, 18S ep20).

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS↗
DOE OSTI2020

Modifications to the Bubble experiment and preparation for additional irradiations

SHINE Medical Technologies is planning to use neutron-induced fission in a subcritical low-enriched-uranium uranyl sulfate target solution for production of 99 Mo. During this operation, the solution will undergo self-heating due to fissioning of the uranium, radiolytic decomposition of the water, and circulation due to thermal gradients generated in the solution, and will be cooled by cooling tubes running through the annulus and from cooling outside the annulus. Because the formation of the radiolysis-induced bubbles (H 2 and O 2 ) and their size and dynamics will impact the operational parameters of the liquid target, an understanding of bubble behavior is critical for the ability to predict the behavior of the target solution during this operation. It is also important to be able to predict the thermal gradients and the circulation in the vessel. Researchers at Argonne National Laboratory have designed an experimental setup to study radiolytic gas formation in uranyl sulfate under direct electron beam irradiation and have conducted initial experiments. Results of those experiments provided invaluable information on thermal hydraulic behavior of the solution and some information on bubble formation and behavior, but those initial experiments fell short in the measurements of the gas generation rates and bubble behavior. To address the shortcomings of the original experiment, the irradiation setup was modified to improve our abilities to measure gas generation rates and measure the temperature distribution in the solution with better precision. Modifications to the experimental setup and preparation for the irradiations are described below.

07 ISOTOPE AND RADIATION SOURCES↗