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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 703 records · Page 39
All sourcesNASA NTRSDOE OSTI
DOE OSTI2022

DC Solar for All: Implementation Plan to Scale Low- and Moderate- Income Community Solar + Storage Resilience Hubs in the District of Columbia

This implementation plan discusses the District of Columbia's strategy to combine low-income community solar projects with resilience technologies. Through the technical and financial support offered by the Inclusive Shared Solar Initiative and building on extensive stakeholder engagement in LMI neighborhoods around the District, the District of Columbia team expects to reduce energy burdens for LMI residents, address barriers to and streamline SfA program enrollment, and support the development of innovative benefit delivery models, including a community solar-supported climate resilience center.

14 SOLAR ENERGY↗
DOE OSTI2023

Assessing the Behavior of Moderately Volatile Elements on the Moon in Order to Constrain Processes of Magmatic Evolution and Planetary Accretion

Heterogeneous isotopic compositions of Zn and Ga in lunar basalts and highlands rocks indicate that secondary processing affected the stable isotopic composition of major lunar reservoirs. It follows that these fractionating processes must be identified and characterized in order to make robust estimates for the isotopic composition of the mare basalt source regions or the bulk silicate Moon (BSM). Contrary to previous assertions (e.g., Kato & Moynier, 2017), MVEs such as Zn and Ga do not behave similarly on the Moon, in line with differences in their chemical behavior and volatility. There is clear evidence that impact reworking fractionates zinc isotopes but, in addition, zinc isotopes are also highly sensitive to the formation of Ti-bearing oxides such as ilmenite. In contrast, gallium is far less susceptible to volatile reworking, but its isotopic composition is fractionated during incorporation into plagioclase (Wimpenny et al., 2022; Render et al., 2023). Based on these findings we conclude that current isotopic compositions of Zn and Ga in lunar rocks, such as those measured for the mare basalt suite, are unlikely to be representative of the bulk Moon when it accreted. As such, estimates for the MVE isotopic composition of the BSM derived from mare basalts may not be accurate, which may have implications for the incorporation of these data into dynamical models of the Moon’s formation. In the following, we discuss the main findings from this project in more detail, focusing on the behaviour of zinc and gallium isotopic systematics in lunar rocks and the processes that control their isotopic fractionation on the Moon.

58 GEOSCIENCES↗
DOE OSTI2024

RF Sources for Electron Accelerators With a focus on high-duty-factor, low-to-moderate energy architectures

A charged particle, such as an electron or a proton, is accelerated through its interaction with either a static (DC) or time-varying (RF) electric field. The magnitude of the accelerating field, or gradient, is typically given in units of volts per meter; in charged-particle accelerators, fields are usually expressed as kV/m or MV/m. The energy of the accelerated particle is usually expressed in terms of electron volts, or eV. An electron starting at rest at ground potential, and accelerated to an electrode with a potential of 1 kV, will have an energy of 1 keV.

43 PARTICLE ACCELERATORS↗
DOE OSTI2024

An OVERVIEW of MICROPHONICS in CEBAF and CURRENT MODERATION TECHNIQUES

Superconducting RF (SRF) structures are susceptible to frequency detuning from external vibrations and modal mechanical resonances in the structure. These small disturbances, known as microphonics, require additional RF power in CW accelerating structures since the frequency is constantly shifting. In the Jefferson Lab CEBAF accelerator, time and frequency data of this frequency shift have been recorded for many years, allowing a retrospective analysis of different microphonics-mitigation techniques. Some of these techniques are specific to the design of each CEBAF cryomodule, for example implementing BNNT damping material on the cavity string. Other techniques are universal such as affixing vacuum lines and reinforcing waveguide structures.

Powers, Tom↗
DOE OSTI2025

Neutron moderation at IPF

We discuss here the possibility of using the Isotope Production Facility (IPF) at LANSCE to test the feasibility and performance of a graphite cube to create a neutron target. The idea of a neutron target enables the measurement of neutron induced reactions in inverse kinematics. This idea is part of the LANSCE strategy to stay a worldwide leader for neutron-induced research. The proof of-principle is the core of the LDRD project 20240004DR. The first steps are a series of activation experiments with different neutron energy distributions. Figs. 1 and 2 show a graphite cube built and simulated from pieces available at LANSCE. First activation experiments have already been performed at lower neutron energies utilizing (p,n) reactions on Li and Be.

73 NUCLEAR PHYSICS AND RADIATION PHYSICS↗
DOE OSTI2025

Development Efforts for Detritiating Legacy Heavy Water Moderator

Conclusions • Department of Energy is evaluating reclaiming contaminated heavy water to commercial virgin heavy water specifications • SRNL evaluated leading commercial technologies to detritiate heavy water • To minimize the process hazards, water distillation was proposed as the best candidate • Addition of LPCE and cryogenic distillation can help process 100% of water with little to no waste storage • Significant advances over the past 40 years, but demonstration system needed to prove necessary detritiation factors for heavy water

Angelette, Lucas M. [Savannah River National Labor↗
DOE OSTI2023

Trust in News as Moderated by Known Truth Assessments and Source

Disinformation has become a problem in various spaces, from social media to organizations. Given the lack of evidence and transparency surrounding organizational disinformation, we aim to understand issue of information exposure effect and source trust from the lens of traditional information consumption online. Using an online experiment and multi-level mixed-effects modeling, we find that the exposure effect exists even over only two exposures to a headline, as long as participants are not shown fact-checking. Fact-checking can be effective in reducing the impact of the exposure effect. Additionally, we find that participants trusted sources significantly more before seeing the headlines. The possible presence of disinformation reduces trust in sources, even when considered highly neutral and reputable. These findings can inform simulations of agent interactions with misinformation as well as future experimental designs focused on evaluations of belief and trust based on recognizability of a source.

99 GENERAL AND MISCELLANEOUS↗
DOE OSTI2010

Improving Natural Uranium Utilization By Using Thorium in Low Moderation PWRs - A Preliminary Neutronic Scoping Study

The Th-U fuel cycle is not quite self-sustainable when used in water-cooled reactors and with fuel burnups higher than a few thousand of MWd/t characteristic of CANDU reactors operating with a continuous refueling. For the other industrially mature water-cooled reactors (i.e. PWRs and BWRs) it is economically necessary that the fuel has enough reactivity to reach fuel burnups of the order of a few tens of thousand of MWd/t. In this particular case, an additional input of fissile material is necessary to complement the bred fissile U-233. This additional fissile material could be included in the form of Highly Enriched Uranium (HEU) at the fabrication of the Th-U fuel. The objective of this preliminary neutronic scoping study is to determine (1) how much HEU and, consequently, how much natural uranium is necessary in such Th-U fuel cycle with U recycling and (2) how much TRansUranics (TRU=Pu, Np, Am and Cm) are produced. These numbers are then compared with those of a standard UO2 PWR. The thorium reactors considered have a homogeneous hexagonal lattice made up of the same (Th-U)O2 pins. Furthermore, at this point, we are not considering the use of blankets inside or outside the core. The lattice pitch has been varied to estimate the effect of the water-to-fuel volume ratio, and light water as well as heavy water have been considered. For most cases, an average burnup at discharge of 45,000 MWd/t has been considered.

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS↗