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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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This work highlights the challenges of weak photoluminescence, the limited choice of substrates, unwanted impurity phases, and Ruddlesden–Popper phases in the moderate-temperature synthesized chalcogenide perovskites.
Set of process and control variables corresponding to the cryogenic moderator system at the SNS. The data corresponds to 54 measurement signals (pressure, temperature, flows, valve position, etc.) spanning from 2021/10/20 to 2021/10/21.
The nature of seismic sources for moderately large (moment magnitude, M w 5.0–6.5) events are commonly characterized by their moment tensor (MT) solutions and obtained by inversion of regional distance (200–1600 km) long‐period (20–50 s) waveforms. Regional MT estimates are often calculated from average plane‐layered, one‐dimensional (1D) velocity models. However, 1D model calculations can produce misfits in the arrival times and waveform shapes that introduce errors, particularly at longer distances or for shorter periods, which are necessary for analyzing lower magnitude events. Approximate Earth models (e.g., 1D) representing broad areas may be inadequate, particularly in the crust and uppermost mantle of tectonically complex regions. In this study, we show how a three‐dimensional (3D) Earth model obtained from full waveform inversion tomography can improve waveform fits and decrease phase errors. We developed a platform and workflow to perform routine 3D MT inversions and inverted MTs for 25 earthquakes in the western United States and seven nuclear explosions using an average 1D and a recent 3D Earth model, WUS256 (Rodgers et al., 2022). Using the 3D model improves waveform fits (variance reduction and phase time shifts) compared with the 1D model, and the 3D MT solutions are stable across large distances. This study shows that 3D models obtained from full waveform tomography can improve MTs and source characterization especially at far regional distances (>800 km).
This report is a major update of the report ”Cubical moderators for the Neutron Target Demonstator (NTD), LA-UR-23-33899”. It serves as a documentation of milestone M1 of the LDRD project 20240004DR.
First and second order density corrections to transport coefficients of moderately dense gas
Study of coaxial Hall current accelerators at moderate pressures
Dynamic equations and Reynolds number approximations for moderately weak turbulence
Delay time for bubble formation associated with heating surface thermal layer formation in water moderated reactors
Moderately long-range relativistic intermolecular forces, obtaining interaction energies
FORTRAN 4 program /P1-GAS/ calculates the P-O and P-1 transfer matrices for neutron moderation in a monatomic gas. The equations used are based on the conditions that there is isotropic scattering in the center-of-mass coordinate system, the scattering cross section is constant, and the target nuclear velocities satisfy a Maxwellian distribution.
Regeneratively cooled nozzle for tungsten water moderated nuclear rocket system
Vascular responses and wound repair in mice exposed to moderate and severe hypoxia
Comparison of absolute calculated and measured gamma and neutron doses in tungsten water- moderated critical assembly
Fast and moderated nuclear reactors, and feasibility of low-power lightweight reactors for nuclear rocket engine applications
Flow visualization and containment tests in directed-wall-jet vortex tube with radial outflow and moderate superimposed axial flows
System dynamics and control analysis of tungsten water moderated nuclear rocket
Postshutdown cooling requirements of tungsten water moderated nuclear rocket engines
Vibration tests of concentric tube fuel element support structure for Tungsten Water Moderated Reactor