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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 991 records · Page 55
All sourcesNASA NTRSDOE OSTI
NASA NTRS2007

Optical Modeling Activities for NASA's James Webb Space Telescope (JWST): Overview and Introduction of Matlab Based Toolkits used to Interface with Optical Design Software - 4

This is part four of a series on the ongoing optical modeling activities for James Webb Space Telescope (JWST). The first two discussed modeling JWST on-orbit performance using wavefront sensitivities to predict line of sight motion induced blur, and stability during thermal transients. The third investigates the aberrations resulting from alignment and figure compensation of the controllable degrees of freedom (primary and secondary mirrors), which may be encountered during ground alignment and on-orbit commissioning of the observatory. The work here introduces some of the math software tools used to perform the work of the previous three papers of this series. NASA has recently approved these in-house tools for public release as open source, so this presentation also serves as a quick tutorial on their use. The tools are collections of functions written in Matlab, which interface with optical design software (CodeV, OSLO, and Zemax) using either COM or DDE communication protocol. The functions are discussed, and examples are given.

Howard, Joseph↗
NASA NTRS2013

Electrochemical Disinfection Feasibility Assessment Materials Evaluation for the International Space Station

The International Space Station (ISS) Program recognizes the risk of microbial contamination in their potable and non-potable water sources. The end of the Space Shuttle Program limited the ability to send up shock kits of biocides in the event of an outbreak. Currently, the United States Orbital Segment water system relies primarily on iodine to mitigate contamination concerns, which has been successful in remediating the small cases of contamination documented. However, a secondary method of disinfection is a necessary investment for future space flight. Over the past year, NASA Johnson Space Center has investigated the development of electrochemically generated systems for use on the ISS. These systems include: hydrogen peroxide, ozone, sodium hypochlorite, and peracetic acid. To use these biocides on deployed water systems, NASA must understand of the effect these biocides have on current ISS materials prior to proceeding forward with possible on-orbit applications. This paper will discuss the material testing that was conducted to assess the effects of the biocides on current ISS materials.

Rodriquez, Branelle↗
DOE OSTI2025

A Rapid Procedure Development Approach for Multi-stage Validation of Novel Nuclear Power Plant Systems

The integration of renewable energy sources into the modern grid introduces variability in generation, challenging nuclear reactors to remain economically viable amid low wholesale electricity prices. To address this, Idaho National Laboratory?s Flexible Plant Operation and Generation program explores alternative revenue streams, including commoditizing excess thermal energy. A Thermal Power Dispatch (TPD) system enables steam extraction from the secondary loop for industrial uses like hydrogen production via high-temperature steam electrolysis.

99 - GENERAL AND MISCELLANEOUS↗
DOE OSTI2026

Identifying Decoherence Mechanisms in Superconducting Qubits through Advanced Materials Characterization

Although superconducting qubits have emerged as a leading technology platform for quantum computing through large improvements in device coherence times and gate fidelity in recent years, the presence of defects and impurities at the interfaces and surfaces in the constituent materials continue to limit performance and serve as a critical barrier in achieving scalable quantum systems. Understanding and eliminating these sources of quantum decoherence in superconducting qubit devices requires dedicated studies aimed at establishing robust structure-property relationships that will enable researchers to target and eliminate defects strategically. As part of the Superconducting Materials and Systems (SQMS) center, we have extensively employed state-of-the-art materials characterization techniques, including scanning/transmission electron microscopy, secondary ion mass spectrometry, atom probe tomography, x-ray diffraction, and x-ray photoelectron spectroscopy in conjunction with device measurements to elucidate such relationships. In this talk, I will discuss some of our recent findings, including linking atomic defects to microwave loss in surface oxides, linking impurities in the Josephson Junction to qubit parameters, and linking low temperature precipitates to device performance. By applying these insights, we have been able to strategically develop and implement mitigation strategies for reliable fabrication of high coherence superconducting qubits.

Murthy, A. [Fermilab] (ORCID:0000000176776866)↗
DOE OSTI2026

Identifying Decoherence Mechanisms in Superconducting Qubits through Advanced Materials Characterization

Although superconducting qubits have emerged as a leading technology platform for quantum computing through large improvements in device coherence times and gate fidelity in recent years, the presence of defects and impurities at the interfaces and surfaces in the constituent materials continue to limit performance and serve as a critical barrier in achieving scalable quantum systems. Understanding and eliminating these sources of quantum decoherence in superconducting qubit devices requires dedicated studies aimed at establishing robust structure-property relationships that will enable researchers to target and eliminate defects strategically. As part of the Superconducting Materials and Systems (SQMS) center, we have extensively employed state-of-the-art materials characterization techniques, including scanning/transmission electron microscopy, secondary ion mass spectrometry, atom probe tomography, x-ray diffraction, and x-ray photoelectron spectroscopy in conjunction with device measurements to elucidate such relationships. In this talk, I will discuss some of our recent findings, including linking atomic defects to microwave loss in surface oxides, linking impurities in the Josephson Junction to qubit parameters, and linking low temperature precipitates to device performance. By applying these insights, we have been able to strategically develop and implement mitigation strategies for reliable fabrication of high coherence superconducting qubits.

Murthy, A. [Fermilab] (ORCID:0000000176776866)↗
DOE OSTI2023

Effects of small marine energy deployments on oceanographic systems

The placement and operation of marine energy deployments in the ocean have the potential to change flow patterns, decrease wave heights, and/or remove energy from the oceanographic system. Changes in oceanographic systems resulting from harvesting marine energy, particularly tidal and wave energy, may be of concern. These changes include alterations in nearfield and farfield physical processes, as well as potential secondary environmental effects such as changes in sediment transport patterns, biological processes, or coastal erosion. Knowledge of changes in oceanographic systems associated with marine energy is primarily available from numerical modeling studies, informed by some laboratory tests and very few field measurements. A literature review was conducted using the Tethys knowledge base and other online sources, building on conclusions from the Ocean Energy Systems-Environmental State of the Science report. Potential changes in oceanographic systems that may be caused by marine energy differ between tidal and wave devices because of different extraction mechanisms and siting locations. Numerical models show that tidal extraction on the order of hundreds of megawatts or with significant channel blockage is required to create changes in oceanographic processes that exceed natural variability. Effects from wave energy extraction in arrays are localized and dependent on array spacing and proximity to the shore. Here the available evidence supports the conclusion that the risk of significant environmental effects from such changes could be retired (i.e., less investigation required for every project) for small deployments—those representative of the state of the industry in 2021. Determining changes in oceanographic systems to be low risk for small deployments can thereby streamline environmental consenting by reducing monitoring needs at this early stage in the industry.

54 ENVIRONMENTAL SCIENCES↗
NASA NTRS1982

Observations and analysis of the R Aquarii jet

Ultraviolet, optical and radio observations of the symbiotic star R Aquarii are discussed in the light of the discovery of a bright radio and optical jet from this star. The star is probably a binary with a period of 44 years. The VLA maps of the jet reveal a protruding structure extending approximately 10 arc sec from the central radio source with a position angle virtually identical to that of the optical jet observed at Lick. The observations of R Aqr are interpreted as indicating the existence of an accretion disk around an unseen companion. The hot subdwarf has effective temperature approximately 65,000 K. It is suggested that the Mira primary and the hot secondary are in orbit around each other with a high eccentricity. At periastron the hot subdwarf accretes at super critical rates and a jet forms. It is difficult to understand how an accretion disk would have eclipsed the Mira in 1928-1935 and 1974-1980. The suppression of maximum light in these two periods is interpreted as due to a distortion of the Mira envelope at periastron by the tidal interaction with the secondary. The jet may help to explain the excitation of the R Aqr nebula. It is possible that R Aqr flared up as a nova approximately 1000 years ago forming the nebula.

Kafatos, M.↗
NASA NTRS1988

The stellar wind velocity function for red supergiants determined in eclipsing binaries

The potential for direct measurement of the acceleration of stellar winds from the supergiant component of Zeta Aurigae-type binary stars is discussed. The aberration angle of the interaction shock cone centered on the hot star provides a measure of the velocity of the cool star wind at the orbit of the secondary. This is confirmed by direct observations of stellar wind (P Cygni) line profile variations. This velocity is generally smaller than the final (terminal) velocity of the wind, deduced from the P Cygni line profiles. The contrast between these results and previously published supergiant wind models is discussed. The implication on the physics of energy source dissipation predicted in the theoretical models is considered.

Ahmad, Imad A.↗
NASA NTRS1991

NO(gamma) emission by energy transfer from NO(+) (a) to NO

Ultraviolet emission produced by photoexcitation of NO at 50-80 nm is observed using synchrotron radiation as a light source. The emission increases at an excitation wavelength corresponding to the ionization potential of the NO(+) (a) state. The emission spectra at several excitation wavelengths are dispersed and identified to be mainly the NO(gamma) band. The dependence of emission intensity on gas pressure and delay time indicates that the emission is produced by a secondary reaction, which is attributed to the energy transfer from NO(+) (a) to NO.

Ma, Guang↗
NASA NTRS2019

Episodes of Particle Ejection from the Surface of the Active Asteroid (101955) Bennu

Active asteroids are those that show evidence of ongoing mass loss. We report repeated instances of particle ejection from the surface of (101955) Bennu, demonstrating that it is an active asteroid. The ejection events were imaged by the OSIRIS-REx (Origins, Spectral Interpretation, Resource Identification, and Security–Regolith Explorer) spacecraft. For the three largest observed events, we estimated the ejected particle velocities and sizes, event times, source regions, and energies. We also determined the trajectories and photometric properties of several gravitationally bound particles that orbited temporarily in the Bennu environment. We consider multiple hypotheses for the mechanisms that lead to particle ejection for the largest events, including rotational disruption, electrostatic lofting, ice sublimation, phyllosilicate dehydration, meteoroid impacts, thermal stress fracturing, and secondary impacts.

Lauretta, D. S.↗
NASA NTRSDate not supplied

Biosentinel: Update on Extended Mission Operations

BioSentinel has achieved unprecedented performance of an SLS secondary payload due to preparation, planning, and a robust design. Following the conclusion of the primary science mission in April 2023, the Linear Energy Transfer (LET) Spectrometer has continued to collect solar and galactic radiation data from its unique location in heliocentric orbit. The free space dataset offered by the BioSentinel LET is a valuable source of data for both model validation and future mission planning. As the spacecraft travels farther from Earth it is poised to provide longitudinally distributed measurements of solar particle events during solar maximum. Flight heritage has now been gained on many of the novel spacecraft components. The spacecraft bus continues to operate within the design envelope. The 3D-printed cold gas propulsion system provides momentum unloading from the reaction wheels. The power system has maintained power positive levels during flight. The IRIS radio communicates on a weekly basis with the Deep Space Network. The extended mission operations are allowing the team to characterize the performance of the spacecraft components over longer durations of operations. NASA Ames led development of the BioSentinel spacecraft and mission operations. The novel subsystems and COTS components that comprise the BioSentinel bus can serve as a template for future deep space missions. With over a year of continuous operations, the data will inform the next generation of interplanetary smallsat missions.

BioSentinel↗
NASA NTRS2014

Looking for a Source of Water in Martian Basltic Breccia NWA 7034

The recently described martian meteorite NWA 7034 has high water content compared to other SNC meteorites. Deuterium to hydrogen isotope ratio measurements indicates that there are two distinct delta-D components in NWA 7034, a low temperature (150-500degC) light component around -100per mille and a high temperature (300-1000degC) heavy component around +300per mille. NWA 7034 contains iron-rich phases that are likely secondary aqueous alteration products. They are commonly found as spheroidal objects of various sizes that are often rich in Fe-Ti oxides and possibly iron hydroxides. Iron oxides and oxyhydroxides are very common in weathered rocks and soils on Earth and Mars and they are important components of terrestrial and Martian dust. In NWA 7034 iron-rich phases are found throughout the fine-grained basaltic groundmass of the meteorite. The total amount of martian H2O in NWA 7034 is reported to be 6000 ppm, and in this study we attempt to determine the phase distribution of this H2O by texturally describing and characterizing hydrous phases in NWA 7034, using Fourier transform infrared spectrometry (FTIR) and transmission electron microscopy (TEM).

Muttik, N.↗
NASA NTRS1972

Aeroacoustic characteristics of jet flap type exhausts.

This work which is intended to shed more light on the acoustic and fluid dynamic characteristics of jet flap type exhaust flows, reports and discusses some typical experimental results obtained with cold model air jets in a reverberation chamber. Acoustic data on the total sound power output and the overall noise spectrum of various jet flap configurations are given and compared with data from conventional circular jets. In addition various flow data for the same jets resulting from hot wire measurements are reported and general conclusions are obtained regarding the expected noise source distribution. The results indicate the dependence of the acoustic and flow characteristics on the major nozzle parameters. For the jet flaps the total radiated sound power is found to follow a 3 to 6 power of the exhaust velocity while for the circular jets the 8 power law is confirmed. The noise produced in the secondary mixing region downstream of the flap trailing edge tends to exceed the noise issuing from the primary mixing region.

Gruschka, H. D.↗
NASA NTRS1992

Phobos and Deimos are sources of meteoroids

Data of Pioneer 10 meteoroid penetration detectors were revised taking into account the orientation of detectors and the spacecraft velocity relative to the sporadic meteor flux. The meteor flux density increases as an exponent to the orbit of Mars for two times for the particles with masses greater than 10(exp -6) g and six times for the particles with masses greater than 10(exp -12) - 10(exp -9) g then decreases after the orbit. Ejections of secondary meteoroid particles from surfaces of Phobos and Deimos are a possible explanation for the increase in meteoroid flux.

Andreev, V. V.↗
DOE OSTI2021

Uranium Attenuated by a Wetland 50 Years after Release into a Stream

: Wetlands have several important roles in the hydrological cycle, including maintaining water quality by removing surface and groundwater contaminants. Over time, the wetlands themselves can become contaminated, posing a secondary environmental threat. The objective of this study was to calculate the inventory of uranium (U) remaining in a wetland 50 years after the Fuel Fabrication Facility on the Savannah River Site located in South Carolina released 43.5 Mg of U into the nearby environment. Over 232 700 gamma spectra and their associated global positioning system (GPS) coordinates were collected and collated into a map of the contaminated land area. Five core samples were also collected that contained U concentrations as high as 14 099 mg/kg (background levels are about 2.7 mg/kg U). The contaminated area was 278 000 m2 , and it contained 36.2 Mg U, about 83% of the U released. About 80% of the U in the wetland was concentrated in a former beaver pond, a 73 000 m2 area (26% of the contaminated area). This contaminated wetland area was almost 2 km from the source, indicating that it comprised unique hydro-biogeochemical properties for immobilizing the released U. To the best of our knowledge, this is the first data-rich study to quantify the long-term effectiveness of a wetland to immobilize inorganic contaminants. Significant environmental changes to the system, such as those associated with hydrology, forest fires, or anthropogenic land use, may alter the complex hydro-biogeochemical interactions necessary for the long-term immobilization of the U.

Contaminant inventory↗
DOE OSTI2023

Performance Assessment Maintenance Plan for the Active Low-Level Burial Ground Trenches 31, 34, and 94 at the Hanford Site

This report documents the maintenance plan for the Hanford Site 200 West Area Active Low-Level Burial Ground Trenches 31 and 34 and 200 East Area Active Trench 94 performance assessment (PA). The PA maintenance plan is one of several supporting documents that are compendiums to the active trenches (Trenches 31, 34, and 94) PA as required in DOE O 435.1, Radioactive Waste Management . The PA is documented in DOE/RL-2021-26, Performance Assessment of Active Trenches in 200 East and West Low-Level Burial Grounds at the Hanford Site . This plan follows the requirements and outline specified in the applicable U.S. Department of Energy (DOE) standard used for developing documents supporting DOE-STD-5002-2017, Disposal Authorization Statement and Tank Closure Documentation . This maintenance plan summarizes the following major activities DOE plans to conduct to maintain the Trenches 31, 34, and 94 PA: Monitoring; Research and development; Planned reviews and analyses; Revisions of Trenches 31, 34, and 94 PA. The planned research and development activities relate to evaluating the key assumptions, including evaluating conceptual model assumptions and parameter value assumptions used in the PA. The planned research and development activities include those that are designed to track the release mechanisms for Category 1, Category 3, and uranium billet waste sources, as well as continued characterization and related modeling of the natural environment in the Central Plateau of the Hanford Site. In addition, the planned research and development activities include focused testing and evaluation of engineered and natural materials to reduce the uncertainty in the conceptual models and parameter values used in the PA. All key and secondary issues identified during the review of the PA by the Low-Level Waste Disposal Facility Federal Review Group have been resolved prior to finalization of the PA. There are no outstanding issues.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
NASA NTRS1994

Meso-beta scale numerical simulation studies of terrain-induced jet streak mass and momentum perturbations

An in-depth analysis of observed gravity waves and their relationship to precipitation bands over the Montana mesonetwork during the 11-12 July 1981 CCOPE case study indicated two episodes of coherent waves. While geostrophic adjustment, shearing instability, and terrain were all implicated separately or in combination as possible wave generation mechanisms, the lack of upper-air data within the wave genesis region made it difficult to define the genesis processes from observations alone. The first part of this paper, 3D Numerical Modeling Studies of Terrain-Induced Mass/Momentum Perturbations, employs a mesoscale numerical model to help diagnose the intricate early wave generation mechanisms during the first observed gravity wave episode. The meso-beta scale numerical model is used to study various simulations of the role of multiple geostrophic adjustment processes in focusing a region for gravity wave genesis. The second part of this paper, Linear Theory and Theoretical Modeling, investigates the response of non-resting rotating homogeneous and continuously stratified Boussinesq models of the terrestrial atmosphere to temporally impulsive and uniformly propagating three-dimensional localized zonal momentum sources representative of midlatitude jet streaks. The methods of linear perturbation theory applied to the potential vorticity (PV) and wave field equations are used to study the geostrophic adjustment dynamics. The total zonal and meridional wind perturbations are separated into geostrophic and ageostrophic components in order to define and follow the evolution of both the primary and secondary mesocirculations accompanying midlatitude jetogenesis forced by geostrophic adjustment processes. This problem is addressed to help fill the gap in understanding the dynamics and structure of mesoscale inertia-gravity waves forced by geostrophic adjustment processes in simple two-dimensional quiescent current systems and those produced by mesoscale numerical models simulating the orographic and diabatic perturbation of three-dimensional quasi-geostrophically balanced synoptic scale jet streaks associated with complex baroclinic severe storm producing environments.

Lin, Yuh-Lang↗