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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 1,675 records · Page 93
All sourcesNASA NTRSDOE OSTI
NASA NTRSDate not supplied

Navigating the Complexities of Safety and Mission Assurance Across NASA's Partnership Landscape

As NASA increasingly pursues collaborative public-private partnerships and international efforts to advance space exploration goals, ensuring robust safety and mission assurance protocols has become more complex. The evolving dynamics introduce multifaceted challenges spanning regulatory oversight, governance and acquisition models, and technical standardization. To address these issues, NASA plans to prioritize deeper integration of safety and mission assurance principles from the formulation and acquisition stages when structuring partnerships and contracts. This embeds appropriate oversight from the start. Additionally, it is vital to establish an enterprise-level capability focused on identifying and resolving cross-cutting risks that transcend individual missions. Together, all these initial thoughts will form the basis of a broad roadmap of decisions that aims to ensure strategic alignment from policy to implementation allowing NASA to harmonize the currently fragmented safety and mission assurance ecosystem as it navigates the complexities introduced by the new era of public-private space partnerships.

Johnny T Nguyen↗
NASA NTRSDate not supplied

Navigating the Complexities of Safety and Mission Assurance Across NASA's Partnership Landscape

As NASA increasingly pursues collaborative public-private partnerships and international efforts to advance space exploration goals, ensuring robust safety and mission assurance protocols has become more complex. The evolving dynamics introduce multifaceted challenges spanning regulatory oversight, governance and acquisition models, and technical standardization. To address these issues, NASA plans to prioritize deeper integration of safety and mission assurance principles from the formulation and acquisition stages when structuring partnerships and contracts. This embeds appropriate oversight from the start. Additionally, it is vital to establish an enterprise-level capability focused on identifying and resolving cross-cutting risks that transcend individual missions. Together, all these initial thoughts will form the basis of a broad roadmap of decisions that aims to ensure strategic alignment from policy to implementation allowing NASA to harmonize the currently fragmented safety and mission assurance ecosystem as it navigates the complexities introduced by the new era of public-private space partnerships.

Johnny T Nguyen↗
DOE OSTI2025

Insights from Femtosecond Transient Absorption Spectroscopy into the Structure–Function Relationship of Glyceline Deep Eutectic Solvents

This study aimed to determine the structure–function relationship (SFR) for ChCl–glycerol mixtures, a deep eutectic solvent (DES), by investigating their microscopic solvation dynamics and how it relates to their macroscopic properties across varying concentrations of ChCl. Femtosecond transient absorption (fs-TA) spectroscopy revealed two distinct solvation dynamics time constants: τ 1 , governed by glycerol–glycerol interactions, and τ 2 , dominated by the choline response. The τ 2 minimum at 25–30 mol % ChCl closely aligned with the eutectic composition (~33.33 mol % ChCl), where the glycerol network was the most organized and the choline ions exhibited the fastest relaxation. The viscosity decreased sharply up to ~25 mol % ChCl and then plateaued, while the conductivity increased monotonically with ChCl concentration, reflecting enhanced ionic mobility. The density decreased with both increasing ChCl concentration and temperature, indicating disrupted hydrogen bonding and reduced molecular packing. The polarity, measured using betaine-30 (B30) and the E T (30) polarity scale, increased steeply up to approximately 25 mol % ChCl before reaching a plateau. These findings identified the eutectic composition as the optimal concentration range for balancing stability, fluidity, conductivity, and enhanced dynamics within the glycerol system.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2021

Using the CYBER-Champ Model to Determine Cyber Competencies and Role Alignment

Cybersecurity roles, tasks, and skills are seen by many organizations as nonessential, abstract, or complicated. Although standards are in place, such as the National Institute of Standards and Technology (NIST) 800-181 document titled “Workforce Framework for Cybersecurity (NICE Framework)” available since September 2012, companies are still showing security vulnerabilities in their cyber networks (Hatzes, 2020). Barriers towards creating a cyber-ready workforce are not always due to a lack of resources, but often caused by organizational structure. The need for cyber-cognizant job postings, improved communication between Operational Technology (OT) and Information Technology (IT) employees, increases in staffing and funding for cyber teams, and better communication of standards and training can all contribute to increasing an organization’s cyber resilience. Cybersecurity Competency Health and Maturity Progression model (CYBER-CHAMP) is a model aimed at evaluating an organization’s structure and individual employee’s cyber knowledge and helps develop a plan to reach competency. This model was used to engage with organizations to promote proper cyber protocols and policies. The aim of this paper is to answer if it is possible for an organization to build a cyber-ready workforce by providing education and training options for current employees and prepare the future workforce to be ready on day one of employment. Both open source and firsthand interviews with organizations were used to conduct the research contained in this document. Further research may include additional development to the CYBER-CHAMP model and its delivery platform.

99 GENERAL AND MISCELLANEOUS↗
DOE OSTI2023

Mass Dependence of Galaxy–Halo Alignment in LOWZ and CMASS

We measure the galaxy-ellipticity (GI) correlations for the Sloan Digital Sky Survey Data Release 12 LOWZ and CMASS samples with the shape measurements from the DESI Legacy Imaging Surveys. We model the GI correlations in an N-body simulation with our recent accurate stellar–halo mass relation from the Photometric object Around Cosmic webs (PAC) method. The large data set and our accurate modeling turns out an accurate measurement of the alignment angle between central galaxies and their host halos. We find that the alignment of central elliptical galaxies with their host halos increases monotonically with galaxy stellar mass or host halo mass, which can be well described by a power law for the massive galaxies. We also find that central elliptical galaxies are more aligned with their host halos in LOWZ than in CMASS, which might indicate an evolution of galaxy–halo alignment, though future studies are needed to verify this is not induced by the sample selections. In contrast, central disk galaxies are aligned with their host halos about 10 times more weakly in the GI correlation. These results have important implications for intrinsic alignment (IA) correction in weak lensing studies, IA cosmology, and theory of massive galaxy formation.

79 ASTRONOMY AND ASTROPHYSICS↗
DOE OSTI2024

Atomic-Scale Scanning of Domain Network in the Ferroelectric HfO 2 Thin Film

Ferroelectric HfO 2 -based thin films have attracted much interest in the utilization of ferroelectricity at the nanoscale for next-generation electronic devices. However, the structural origin and stabilization mechanism of the ferroelectric phase are not understood because the film is typically nanocrystalline with active yet stochastic ferroelectric domains. Here, in this study, electron microscopy is used to map the in-plane domain network structures of epitaxially grown ferroelectric Y:HfO 2 films in atomic resolution. The ferroelectricity is confirmed in free-standing Y:HfO 2 films, allowing for investigating the structural origin for their ferroelectricity by 4D-STEM, high-resolution STEM, and iDPC-STEM. At the grain boundaries of <111>-oriented Pca2 1 orthorhombic grains, a high-symmetry mixed-(R3m, Pnm2 1 ) phase is induced, exhibiting enhanced polarization due to in-plane compressive strain. Nanoscale Pca2 1 orthorhombic grains and their grain boundaries with mixed-(R3m, Pnm2 1 ) phases of higher symmetry cooperatively determine the ferroelectricity of the Y:HfO 2 film. It is also found that such ferroelectric domain networks emerge when the film thickness is beyond a finite value. Furthermore, in-plane mapping of oxygen positions overlaid on ferroelectric domains discloses that polarization is suppressed at vertical domain walls, while it is active when domains are aligned horizontally with subangstrom domain walls. In addition, randomly distributed 180° charged domain walls are confined by spacer layers.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2024

Ce- and Ni-Codoped Double PrBaMn 2 O 5 Perovskite as a Ceramic SOFC Anode

This study explores the efficacy of cerium introduction, both on its own and in combination with nickel, into PrBaMn 2 O 5+δ (PBM) structures to enhance solid oxide fuel cell (SOFC) anodes. We synthesized Pr 1–x Ce x BaMn 2 O 5+δ compositions for x values of 0.05 (PrCe5) and 0.1 (PrCe10), as well as a nickel-doped variant (PrCe5Ni), assessing their performance under H 2 – 3% H 2 O reducing conditions pertinent to SOFC anode operations. Our findings reveal that the PrCe5 composition exhibits a thermal expansion coefficient (TEC) that not only improves upon that of the Ce-free counterpart but also aligns closely with the TEC standards of prevalent SOFC electrolytes. A notable advancement was achieved with the application of a 3.5 μm gadoliniadoped ceria (GDC) buffer layer through physical vapor deposition, effectively mitigating chemical interactions between PBM-based anodes and yttria-stabilized zirconia (YSZ) electrolytes, a concern highlighted by in situ neutron diffraction analyses. Electrochemical impedance spectroscopy, conducted over 220 h in a H 2 –3% H 2 O atmosphere at 750 °C, demonstrated that the optimal 3.5 μm thickness of the GDC buffer layer significantly minimizes the area-specific resistance (ASR) degradation rate to 0.002 Ω cm 2 /h, markedly outperforming both thinner (1 μm) and thicker (8 μm) GDC layers, which showed higher degradation rates of 0.15–0.2 Ω cm 2 /h due to the diffusion of Ba ions or delamination. Moreover, cerium doping fosters superior microstructural stability and obviates barium diffusion, thereby suggesting an enhanced durability of the doped anodes over their lifespan. Integrating nickel into the PrCe5 structure halved the ASR to 0.5 Ω cm 2 at 750 °C, situating it well within the ideal performance range for SOFC anodes. Furthermore, the enhancement brought about by simultaneously doping PBM with cerium and nickel, which fundamentally relies on the critical contributions of defect chemistry and crystal structure, highlights the significance of these fields in creating sophisticated materials for energy related applications.

25 ENERGY STORAGE↗
NASA NTRS1984

Flux transfer events - Scale size and interior structure

The first direct investigation of the spatial properties of flux transfer events (FTEs) at the earth's dayside magnetopause are reported. Simultaneous magnetometer and plasma data from the ISEE 1 and 2 satellites are combined to show that magnetosheath FTEs can have a scale size of the order of an earth radius in the magnetopause normal direction. It is confirmed that the magnetic field within the events appears to be twisted, this twisting corresponding to a core field-aligned current of a magnitude of a few tens of thousands of A. Also shown is evidence for plasma vorticity in FTEs. The transverse flow and field perturbations accompanying the three events studied obey approximately the Walen relation for a propagating Alfven wave.

Saunders, M. A.↗
NASA NTRS1986

Directional solidification and annealing of Mn55Al45 alloys

The use of directional solidification to produce aligned or magnetic microstructures for the MnAl alloy and the effect of annealing on the bulk magnetic properties of the alloy are investigated. The phase composition, cylindrically shaped magnetization, and room-temperature magnetization of the samples are analyzed. The microstructure of a directionally solidified Al-Mn alloy is characterized by a two-phase structure consisting of randomly-oriented Al-rich fibers of about 40 at. pct Al dispersed in a textureless matrix of about 50 at. pct Al; the matrix phase contains at least 50 wt pct of the metastable and ferrimagnetic tau-phase, and the Al-rich fibers as a precipitated Cr5Al8-type Al-Mn phase. Significant macrosegregation for the thermally stable growth-up orientation is detected. The data reveal that the annealing enhances the cell-like microstructure observed transverse of the solidification direction and increases remanent magnetization and intrinsic coercivity.

Pirich, Ronald G.↗
NASA NTRS1990

Monitoring Small Deformations In An Instrument

Relatively simple source/detector pairs measure changes affecting optical alignment. System for monitoring small thermal, gravitational, and dynamical deformations in x-ray telescope includes two sources of infrared light, each associated with dual-axis, position-sensing photodiode. Principle of operation straightforward and applicable to monitoring of small lateral translations and/or rotations between different parts in machinery, buildings, bridges, ships, and other large structures.

Hagopian, John G.↗
NASA NTRS1992

Survey of transient magnetic field events in the dayside magnetosphere

Data acquired with AMPTE/CCE are employed to investigate transient magnetic field events (TMFEs) in the dayside magnetosphere. TMFEs are found to occur more frequently near the magnetopause than deep in the magnetosphere, and the amplitude of a TMFE increases as the spacecraft comes closer to the magnetopause. It is inferred that they are generated at the magnetopause. From the MLT dependence of the rotational polarity of the transverse magnetic field perturbation, it is suggested that TMFE structures move longitudinally away from the noon meridian. Latitudinal motion away from the equator is also inferred from the latitudinal dependence of the occurrence rates of the standard and reverse events. The motion of TMFEs is tailward in both azimuthal and north-south directions. It is suggested that TMFEs carry oppositely directed twin field-aligned currents, separated in the direction perpendicular to the direction of motion and having the same current intensity.

Kawano, H.↗
NASA NTRS1993

The JPL Phase B interferometer testbed

Future NASA missions with large optical systems will require alignment stability at the nanometer level. However, design studies indicate that vibration resulting from on-board disturbances can cause jitter at levels three to four orders of magnitude greater than this. Feasibility studies have shown that a combination of three distinct control layers will be required for these missions, including disturbance isolation, active and passive structural vibration suppression, and active optical pathlength compensation. The CSI technology challenge is to develop these design and control approaches that can reduce vibrations in the optical train by a factor of 1000 to 10,000. The focus of the paper is on describing the Phase B Testbed structure and facility, as the experimental results are included in other papers presented at this same conference.

Eldred, Daniel B.↗
NASA NTRS2001

Plasma CVD of Carbon Nanotubes

Carbon nanotubes(CNT) exhibit remarkable mechanical and unique electronic properties and thus have created excitement in the research community about their potential in electronics, computing, sensor and structural applications. Realization of these applications critically depends on the ability to control the properties(such as diameter, chirality) as well purity. We have investigated CNT growth using an inductively coupled plasma(ICP) process using hydrocarbon feedstock. The catalyst required for nanotube growth consists of thin sputtered layers of aluminum and iron(10 nm each) and aligned carbon nanotubes have been obtained. Optical emission diagnostics as well as a plasma modeling effort have been undertaken to understand growth mechanisms. This presentation will discuss growth characteristics under various pressure, power and feedgas compositions and our understanding from modeling and diagnostics.

Delzeit, Lance↗
NASA NTRS2004

Acoustic, Flow Related, and Performance Related Experimental Results for Generation 1.5 High Speed Civil Transport (HSCT) 2-Dimensional Exhaust Nozzles

The principle objectives of the current program were to experimentally investigate the repeatability of acoustic and aerodynamic characteristics of 2D-CD mixer-ejector nozzles and the effects on the acoustic and aerodynamic characteristics of 2D mixer-ejectors due to (1) the configurational variations, which include mixers with aligned CD chutes, aligned convergent chutes, and staggered CD chutes and aerodynamic cycle variables, (2) treatment variations by using different treatment materials, treating the ejector with varying area, location, and treatment thickness for a mixer-ejector configuration, and (3) secondary inlet shape (i.e., a more realistic inlet) and the blockage across the inlet (a possible fin-like structure needed for installation purpose) by modifying one of the inlet of a mixer-ejector configuration. The objectives also included the measurement dynamic pressures internal to the ejector for a few selected configuration to examine the internal noise characteristics.

Salikuddin, M.↗
NASA NTRS2009

NASA Tech Briefs, August 2009

Topics covered include: Aligning a Receiving Antenna Array to Reduce Interference; Collecting Ground Samples for Balloon-Borne Instruments; Tethered Pyrotechnic Apparatus for Acquiring a Ground Sample; Enhanced Video-Oculography System; Joint Carrier-Phase Synchronization and LDPC Decoding; Dual-Polarization, Sideband-Separating, Balanced Receiver for 1.5 THz Modular Battery Charge Controller; Efficient Multiplexer FPGA Block Structures Based on G4FETs; VLSI Microsystem for Rapid Bioinformatic Pattern Recognition; Low-Noise Amplifier for 100 to 180 GHz; Improved Fabrication of Ceramic Matrix Composite/Foam Core Integrated Structures; Inert Welding/Brazing Gas Filters and Dryers; Fabricating Copper Nanotubes by Electrodeposition; Reducing Aerodynamic Drag on Empty Open Cargo Vehicles; Rotary Percussive Auto-Gopher for Deep Drilling and Sampling; More About Reconfigurable Exploratory Robotic Vehicles; Thermostatic Valves Containing Silicone-Oil Actuators; Improving Heat Flux Performance of Flat Surface in Spray-Cooling Systems; Treating Fibrous Insulation to Reduce Thermal Conductivity; Silica-Aerogel Composites Opacified with La(sub0.7)Sr(sub0.3)MnO3; Cyclic Oxidation Behavior of CuCrAl Cold-Sprayed Coatings for Reusable Launch Vehicles; Ceramic Fiber Structures for Cryogenic Load-Bearing Applications; Elastomer Reinforced with Carbon Nanotubes; Biologically Inspired Purification and Dispersion of SWCNTs; A Technique for Adjusting Eigenfrequencies of WGM Resonators; Low-Pressure, Field-Ionizing Mass Spectrometer; Modifying Operating Cycles to Increase Stability in a LITS; Chamber for Simulating Martian and Terrestrial Environments; Algorithm for Detecting a Bright Spot in an Image; Extreme Programming: Maestro Style; Adaptive Behavior for Mobile Robots; Protocol for Communication Networking for Formation Flying; Planning Complex Sequences Using Compressed Representations; and Self-Supervised Learning of Terrain Traversability from Proprioceptive Sensors.

Source record↗
NASA NTRS2006

Interferometer for Low-Uncertainty Vector Metrology

A simplified schematic diagram of a tilt-sensing unequal-path interferometer set up to measure the orientation of the normal vector of one surface of a cube mounted on a structure under test is described herein. This interferometer has been named a "theoferometer" to express both its interferometric nature and the intention to use it instead of an autocollimating theodolite. The theoferometer optics are mounted on a plate, which is in turn mounted on orthogonal air bearings for near-360 rotation in azimuth and elevation. Rough alignment of the theoferometer to the test cube is done by hand, with fine position adjustment provided by a tangent arm drive using linear inchwormlike motors.

Toland, Ronald W.↗
NASA NTRS2021

Dense 3D-Reconstruction from Monocular Image Sequences for Computationally Constrained UAS

The ability to find safe landing sites over complex 3D terrain is an essential safety feature for fully autonomous small unmanned aerial systems (UAS), which requires on-board perception for 3D reconstruction and terrain analysis if the overflown terrain is unknown. This is a challenge for UAS that are limited in size, weight and computational power, such as small rotorcrafts executing autonomous missions on Earth, or in planetary applications such as the Mars Helicopter. For such a computationally constraint system, we propose a structure from motion approach that uses inputs from a single downward facing camera to produce dense point clouds of the overflown terrain in real time. In contrast to existing approaches, our method uses metric pose information from a visual-inertial odometry algorithm as camera pose priors, which allows deploying a fast pose refinement step to align camera frames such that a conventional stereo algorithm can be used for dense 3D reconstruction. We validate the performance of our approach with extensive evaluations in simulation, and demonstrate the feasibility with data from UAS flights.

Brockers, Roland↗
NASA NTRS1978

The relationship between Jovian electrons and solar wind stream structure

Near-earth observations of above-0.22-MeV Jovian electrons by the APL/JHU experiments on IMP-7 and 8 during 1972-1975, a period of stable recurrent solar wind, reveals 19 of 26 events in good association with solar wind streams. This pattern of positive correlation with solar wind streams is also observed in 3-6 MeV data from 1965-1972 during well-defined electron events. During their pre-encounter periods Pioneers 10 and 11 were nearly radially aligned with Jupiter and direct magnetic connection was highly unlikely. Jovian electrons above about 5 MeV in the UCSD experiments on Pioneers 10 and 11 were anticorrelated with solar wind velocity from about 3-4 AU until encounter. Reconstructions of the large-scale interplanetary magnetic field suggest that the near-earth events result from direct connection with the Jovian magnetotail and corotation of quasi-trapped populations while for Pioneer events electrons propagate out from the magnetosphere to a solar wind stream interaction, in along the interaction, then in to Pioneer on undisturbed field lines.

Gold, R. E.↗