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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 1,495 records · Page 83
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NASA NTRS1992

Carbon petrology in cometary dust

Chondritic porous (CP) interplanetary dust particles (IDP's) are collected in the Earth's stratosphere. There exists an extensive database on major and minor element chemistry, stable isotopes, noble gas abundances and mineralogy of many CP IDP's, as well as infrared and Raman spectroscopic properties. For details on the mineralogy, chemistry and physical properties of IDP's, I refer to the reviews by Mackinnon and Rietmeijer (1987), Bradley et al. (1988) and Sandford (1987). Texture, mineralogy (Mackinnon and Rietmeijer, 1987) and chemistry (Schramm et al., 1989; Flynn and Sutton, 1991) support the notion that CP IDP's are a unique group of ultrafine-grained extraterrestiral materials that are distinct from any known meteorite class. Their fluffy, or porous, morphology suggests that CP IDP's probably endured minimal alteration by protoplanetary processes since their formation. It is generally accepted that CP IDP's are solid debris from short-period comets. The evidence is mostly circumstantial but this notion gained significant support based on the comet Halley dust data (Brownlee, 1990). In this paper, I will accept that CP IDP's are indeed cometary dust. The C/Si ratio in CP IDP's is 3.3 times higher than in CI carbonaceous chondrites (Schramm et al. 1989). The intraparticle carbon distribution is heteorogeneous (Rietmeijer and McKay, 1986). Carbon occurs both in oxidized and reduced forms. Analytical electron microscope (AEM) and Raman spectroscopic analyses have shown the presence of several carbon forms in CP IDP's but the data are scattered in the literature. Carbons in cometary CP IDP's are among the most pristine Solar System carbons available for laboratory study. Similar to a recently developed petrological model for the diversity of layer silicates in CP IDP's (Zolensky, 1991) that is useful to constrain in situ aqueous alteration in comets (Rietmeijer and Mackinnon, 1987a), I here present the first effort to develop a petrological concept of carbons in CP IDP's. This concept is useful to constrain comet evolution. I also present the philosophical constraint facing Earth Scientists in studies of protoplanets that require a new approach to cometary dust studies.

Rietmeijer, Frans J. M.↗
NASA NTRS1993

Value added data archiving

Researchers in the Molecular Sciences Research Center (MSRC) of Pacific Northwest Laboratory (PNL) currently generate massive amounts of scientific data. The amount of data that will need to be managed by the turn of the century is expected to increase significantly. Automated tools that support the management, maintenance, and sharing of this data are minimal. Researchers typically manage their own data by physically moving datasets to and from long term storage devices and recording a dataset's historical information in a laboratory notebook. Even though it is not the most efficient use of resources, researchers have tolerated the process. The solution to this problem will evolve over the next three years in three phases. PNL plans to add sophistication to existing multilevel file system (MLFS) software by integrating it with an object database management system (ODBMS). The first phase in the evolution is currently underway. A prototype system of limited scale is being used to gather information that will feed into the next two phases. This paper describes the prototype system, identifies the successes and problems/complications experienced to date, and outlines PNL's long term goals and objectives in providing a permanent solution.

Berard, Peter R.↗
NASA NTRS2004

Dusty Disks, Diffuse Clouds, and Dim Suns: Galactic Science with the Infrared Spectrograph on the Spitzer Space Telescope

The Infrared Spectrograph (IRS) on the Spitzer Space Telescope has now been in routine science operations since Dec. 14,2003. The IRS Science Team has used a portion of their guaranteed time to pursue three major science themes in galactic astronomy: the evolution of protostellar disks and debris disks; the composition and evolution of diffuse matter and clouds in the interstellar medium; and the composition and structure of brown dwarfs and low-mass main-sequence stars. We report here on the results from the first five months of IRS observations in these programs. Full IRS Spectra have already been obtained for large samples of YSO/protoplanetary disks in the Taurus and TW Hya associations, and or debris disks around main-sequence stars, in which many aspects of the evolution of planetary systems can be addressed for the first time. As anticipated, the mid-infrared IRS observations of brown dwarfs have yielded important new information about their atmospheres, including the identification of NH3 and measurements of new methane features. This work is based on observations made with the Spitzer Space Telescope, which is operated by the Jet Propulsion Laboratory, California Institute of Technology under NASA contract 1407. Support for this work was provided by NASA's Office of Space Science.

Roellig, T. L.↗
NASA NTRS2008

Miniature Mass Spectrometers on Space and Planetary Missions

Space flight mass spectrometers contribute our understanding of the origin and evolution of our solar system and even of life itself. This fundamental role has motivated increasing interest in miniature mass spectrometry for planetary missions. Several remarkable new instruments are en route or under development to investigate the composition of planetary bodies such as Mars and comets. For instance, the Sample Analysis at Mars (SAM) suite on the 2009 Mars Science Laboratory (MSL) mission includes a quadrupole mass spectrometer with a sophisticated gas processing system as well as pyrolysis and chemical derivatization protocols for solid samples. Future missions will require even lighter, lower power, and yet more capable mass spectrometers, particularly to analyze samples in situ on planetary surfaces. We have been developing laser-based mass spectrometers for elemental and organic/molecular analysis of rock, ice, or fine particle samples. These typically use time-of-flight (TOF) mass analyzers, which are readily miniaturized and can detect both atomic species and complex organics that occur in a variety of planetary materials. For example, nonvolatile polycyclic aromatic hydrocarbons and kerogen-like macromolecular carbon are found in some carbonaceous meteorites, which derived from asteroid parent bodies. A single focused laser pulse is able to volatilize and ionize some of these compounds for direct TOF analysis. While this is possible without any sample preparation or contact, sensitivity and quantitative performance can improve significantly with some sample handling. As such we have also been examining robotic mechanisms and protocols to accompany space flight mass spectrometers. In addition, sensors in early development may significantly improve these capabilities, via use of techniques such as switchable polarity, ambient pressure, or resonant ionization; tandem mass spectrometry (TOF or ion trap); and chemical imaging.

Brinckerhoff, William↗
NASA NTRSDate not supplied

Development of a Terrain Mapping/Crater Evolution Measurement using Diffractive Optical Elements

When landing on the moon, understanding the interaction of the engine exhaust plume with the lunar surface is critical for the success of the descent and landing flight phases. Two evaluation tools currently used are computational simulations and ground test measurements. Computational simulations require experimental measurements for comparison/validation, but ground test measurements cannot accurately emulate all aspects of an actual lunar landing; flight tests remain the only method of obtaining fully representative data. A terrain mapping/crater evolution measurement system was developed for potential inclusion on a future lander mission. This system uses two stereo cameras viewing a laser dot grid pattern projected on the ground, where the grid is created by shining a laser through one or two diffractive optical elements. CAD simulations of the stereo imaging system are first used to validate the proposed design. Laboratory testing of the system using both a large-scale fixed-geometry crater and a small-scale evolving-geometry crater validate the use of the system for terrain mapping measurements, and for its potential inclusion on a future lander mission.

Joshua M Weisberger↗
NASA NTRSDate not supplied

Development of a Terrain Mapping/Crater Evolution Measurement using Diffractive Optical Elements

When landing on the moon, understanding the interaction of the engine exhaust plume with the lunar surface is critical for the success of the descent and landing flight phases. Two evaluation tools currently used are computational simulations and ground test measurements. Computational simulations require experimental measurements for comparison/validation, but ground test measurements cannot accurately emulate all aspects of an actual lunar landing; flight tests remain the only method of obtaining fully representative data. A terrain mapping/crater evolution measurement system was developed for potential inclusion on a future lander mission. This system uses two stereo cameras viewing a laser dot grid pattern projected on the ground, where the grid is created by shining a laser through one or two diffractive optical elements. CAD simulations of the stereo imaging system are first used to validate the proposed design. Laboratory testing of the system using both a large-scale fixed-geometry crater and a small-scale evolving-geometry crater validate the use of the system for terrain mapping measurements. High-speed, front-illumination shadow particle tracking of particles ejected from the evolving geometry crater is also performed, demonstrating another diagnostic that can be used to further the understanding of plume-surface interactions.

Joshua M Weisberger↗
NASA NTRSDate not supplied

Results of the Preliminary Analyses of Asteroid Ryugu Regolith Samples Returned by the Hayabusa2 Mission

The Hayabusa2 spacecraft returned 5.5g of regolith material from asteroid 162173 Ryugu in December 2021. The samples were maintained in near-vacuum conditions up to and even during many analyses, a factor that was critical for comparisons of Ryugu lithologies to meteorites because of ubiquitous terrestrial alteration of the latter. Observations of asteroid Ryugu by the Hayabusa2 spacecraft found that it is spinning, top-shaped rubble pile, formed from re-accretion of a (probably) small subset of fragments from a disrupted parent asteroid. Samples retrieved from Ryugu by the spacecraft during two brief touchdowns were expected to contain a record of this history, including the formation and early evolution of the parent body, its subsequent impact destruction and partial re-accretion, and later space weathering. The composition of Ryugu was expected to be similar to that of naturally-heated Ivuna-type carbonaceous chondrite meteorites (CI chondrites), based on ground- and spacecraft-based spectroscopy. Six preliminary examination teams investigated the formation history of Ryugu through laboratory analysis of the returned samples over the past 18 months. Specifically, we sought to determine (1) when and where in the Solar System the parent asteroid of Ryugu formed; (2) the original mineralogy, bulk elemental abundances, and chemical compositions of the accreted materials; (3) how these materials evolved through chemical and physical processing of the parent asteroid; and (4) how the parent asteroid was disrupted during impact and reaccumulated into Ryugu. This brief report mainly summarizes results from the mineralogy and petrology subteams, although results of the composition and isotope subteams are also mentioned. To address these issues, we analyzed numerous Ryugu particles up to ~8 mm in size.

Michael Zolensky↗
DOE OSTI2025

Mesoscale Modeling of Dislocation Cell Structure Evolution and Radiation-Induced Segregation in Additively Manufactured Austenitic Stainless Steel

Structural alloys under irradiation develop radiation-induced segregation (RIS) at point defect sinks, which lead to undesired changes in the alloy's properties. Additively manufactured austenitic stainless steels are expected to yield a distinct response to irradiation damage owing to their unique as-printed dislocation cell structure. In this talk, we present the development of a mesoscale model for dislocation cell structure evolution coupled with RIS using the MOOSE framework. The evolution of network dislocations within spatially distinct cells and cell walls are modeled using climb-mediated edge annihilation and generation processes. Starting with initial microstructures of as-printed non-equilibrium segregations at dislocation cell walls, our 2D and 3D simulations explore the effects of irradiation temperature, dose rate, dislocation sink bias, and specimen thickness on microstructure evolution. The results will be compared against experimental characterizations of in-situ and ex-situ ion-irradiated samples, and the implications of evolving cell structure on irradiation damage response will be discussed.

additive manufacturing↗
NASA NTRS2010

The Origins and Evolution of Molecules in Icy Solids

Astronomical observations of the past few decades have revealed the existence of a variety of molecules in extraterrestrial ices. These molecules include H2O, CO, and CO2, and organics such as CH4, CH30H, and C2H6. Some ices are dominated by polar molecules, while non-polar species appear to dominate others. Observations, mainly in the radio and IR regions, have allowed the inference of other solid-phase molecules whose formation remains difficult to explain by gas-phase chemistry alone. Several laboratory research groups have reported on extensive experiments on the solid-phase reaction chemistry of icy materials, generally as initiated by either ionizing radiation or vacuum-UV photons. These experiments not only permit molecular identifications to be made from astronomical observations, but also allow predictions of yet unidentified molecules. This laboratory approach has evolved over more than 30 years with much of the earliest work focusing on complex mixtures thought to represent either cometary or interstellar ices. Although those early experiments documented a rich solid-state photo- and radiation chemistry, they revealed few details of reactions for particular molecules, partly due to the multi-component nature of the samples. Since then, model systems have been examined that allow the chemistry of individual species and specific reactions to be probed. Reactions involving most of the smaller astronomical molecules have now been studied and specific processes identified. Current laboratory work suggests that a variety of reactions occur in extraterrestrial ices, including acid-base processes, radical dimerizations, proton transfers, oxidations, reductions, and isomerizations. This workshop presentation will focus on chemical reactions relevant to solar system and interstellar ices. While most of the work will be drawn from that to which the speaker has contributed, results from other laboratories also will be included. Suggestions for future studies will be made, with an emphasis on some present deficiencies. The speaker's work has been generously supported by these NASA research programs: Cassini Data Analysis, Exobiology, Mars Fundamental Research, Outer Planets Research, Planetary Atmospheres, Planetary Geology and Geophysics, and the NASA Astrobiology Institute.

Hudson, Reggie L.↗
DOE OSTI2022

Electric Field Measurements at the Surface of a Piezoelectric Transformer for Plasma Jet Formation using the Plasma Research Facility at Sandia National Laboratory (Final Report)

The overall goal of this research is to understand how low-temperature non-equilibrium plasmas form directly off the surface of piezoelectric crystals. Specifically, this project aims to temporally and spatially resolve how the electric field evolves on and near the surface of a piezoelectric transformer (PT) at conditions that produce an atmospheric-pressure air plasma jet emanating from the corner of the PT. In this work, we used the Plasma Research Facility (PRF) at Sandia National Laboratory to conduct temporally- and spatially-resolved electric field induced second harmonic (E-FISH) measurements of the electric field at and near the surface of a piezoelectric transformer, providing a fundamental understanding of how piezoelectric crystals can be used for plasma generation. We carried out two Objectives: Objective 1 – The first objective was to measure the temporal and spatial evolution of the electric field along the surfaces approaching the corner of a rectangular PT just below conditions that lead to plasma jet formation. Such a measurement can be used to explain when and where the electric field peaks, leading to plasma formation; Objective 2 – The second objective was to measure the temporal and spatial evolution of the electric field along the surfaces approaching the corner of a rectangular PT just at conditions of plasma jet formation. This, in principle, gives a more accurate determination of how the electric field leads to plasma formation but is more difficult due to the relatively stochastic plasma jet behavior of a PT. This work was complemented by an award from the Sandia PRF, and we worked with Dr. Edward Barnat at the Sandia PRF to carry out these objectives.

70 PLASMA PHYSICS AND FUSION TECHNOLOGY↗
DOE OSTI2021

Fuel Performance Analysis of Chromium-Coated Cladding under Burst Conditions

To reduce the oxidation of zirconium-based alloy cladding at high temperatures, accident tolerant fuel systems have been proposed. Of the concepts identified, chromium-coated cladding has been shown to slow oxidation without greatly impacting the fuel system geometry or neutronic performance. To determine how coated-cladding tubes will perform under high-temperature accident conditions, pressurized-tube burst tests have been performed using the Severe Accident Test Station at Oak Ridge National Laboratory. To begin modeling these tubes to better understand how the coating will impact cladding behavior, these burst tests were simulated with the BISON fuel performance code. Cladding tube surface temperatures for the burst test were developed by fitting thermocouple data into axial and azimuthal profiles, while pressure data were compared until cladding failure. The temperatures at failure and the pressure evolution show relatively good agreement between the simulation and experiment results. This is the first step of a larger effort to simulate the cladding deformation process under high-temperature transient conditions and assess the cladding margin to failure more accurately.

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS↗
DOE OSTI2021

Enabling Efficient Water Splitting with Advanced Materials Designed for High pH Membrane Interface

This project was focused on developing the durable, high-performance materials and interfaces for advanced water splitting, enabling a clear pathway for achieving <$2/Kg H2 (on scale) with efficiency of 43 kWh/kg H 2 via anion exchange membrane (AEM)-based electrolysis. We aimed to advance these final goals via an improved fundamental understanding of both hydrogen and oxygen evolution reactions (HER/OER) leading to novel platinum group metal (PGM)-free catalyst materials in conjunction with critical improvements in membrane and ionomers and gas evolution electrodes with corresponding characterization and testing. Northeastern University (NU) lead this effort focusing on catalyst development and characterization (both in situ and ex situ) while project partners lead improvements in ionomer and membrane materials and will aid in the development of specialized electrode and membrane electrode assemblies. In addition, close collaboration occured with the HydroGEN Energy Materials Network (EMN) National Laboratory consortium including efforts related to use of advanced ionomers, durability protocols and validation of electrolyzer materials (e.g. NREL), multiscale modeling and computation (e.g. LBNL), and molecular dynamics (MD) simulations of the membrane catalyst interface (e.g. SNL). The interactions with HydroGEN included exchange of data and materials as needed to facilitate project success.

08 HYDROGEN↗
NASA NTRS1993

Planetary and satellite x ray spectroscopy: A new window on solid-body composition by remote sensing

The rings and most of the satellites of the outer planets orbit within the radiation belts of their parent bodies. This is an environment with intense fluxes of energetic electrons. As a result, these objects are strong emitters of X-rays. The characteristic X-ray lines from these bodies depend on atomic composition, but they are not sensitive to how the material is arranged in compounds or mixtures. X-ray fluorescence spectral analysis has demonstrated its unique value in the laboratory as a qualitative and quantitative analysis tool. This technique has yet to be fully exploited in a planetary instrument for remote sensing. The characteristic X-ray emissions provide atomic relative abundances. These results are complementary to the molecular composition information obtained from IR, visible, and UV emission spectra. The atomic relative abundances are crucial to understanding the formation and evolution of these bodies. They are also crucial to the proper interpretation of the molecular composition results from the other sensors. The intensities of the characteristic X-ray emissions are sufficiently strong to be measured with an instrument of modest size. Recent developments in X-ray detector technologies and electronic miniaturization have made possible space-flight X-ray imaging and nonimaging spectrometers of high sensitivity and excellent energy resolution that are rugged enough to survive long-duration space missions. Depending on the application, such instruments are capable of resolving elemental abundances of elements from carbon through iron. At the same time, by measuring the bremsstrahlung intensity and energy spectrum, the characteristics of the source electron flux can be determined. We will discuss these concepts, including estimated source strengths, and will describe a small instrument capable of providing this unique channel of information for future planetary missions. We propose to build this instrument using innovative electronics packaging methods to minimize size and weight.

Chenette, D. L.↗
NASA NTRS2018

Human-in-the-Loop Evaluation of Dynamic Multi-Flight Common Route Advisories

Flights often experience large delays when they are routed around weather. Multi-flight common route advisories provide delay recovery by suggesting time-saving re-routes for groups of flights whose current weather-avoidance routes have become outdated because the weather has dissipated and/or moved away. A laboratory evaluation of these advisories was conducted by four subject matter experts having extensive experience in traffic flow management operations. These experts provided a total of 120 data points in the airspace of Houston Center. The multi-flight common route tool provides time-saving route change advisories taking into account flight plans, wind fields, and the spatio-temporal evolution of predicted convective weather. It is not designed to account for complex operational factors such as non-standard sector traversal and interactions with local traffic management initiatives; hence a relatively low percentage (37%) of advisories generated by the tool were rated as acceptable. However, a high percentage (81%) of advisories were rated as acceptable after the subject matter experts used the tool's user interface to make route modifications that accounted for relevant operational factors not considered by the tool. The workload associated with using the tool, as measured by the NASA Task Load Index, was quite low (1.1 on a scale of 0 to 10). The results of this evaluation make a good case for human-automation teaming to design operationally valid weather re-routes for delay recovery.

Traffic Flow Management↗
NASA NTRS2018

Human-in-the-Loop Evaluation of Dynamic Multi-Flight Common Route Advisories

Flights often experience large delays when they are routed around weather. Multi-flight common route advisories provide delay recovery by suggesting time-saving re-routes for groups of flights whose current weather-avoidance routes have become outdated because the weather has dissipated and/or moved away. A laboratory evaluation of these advisories was conducted by four subject matter experts having extensive experience in traffic flow management operations. These experts provided a total of 120 data points in the airspace of Houston Center. The multi-flight common route tool provides time-saving route change advisories taking into account flight plans, wind fields, and the spatio-temporal evolution of predicted convective weather. It is not designed to account for complex operational factors such as non-standard sector traversal and interactions with local traffic management initiatives; hence a relatively low percentage (37%) of advisories generated by the tool were rated as acceptable. However, a high percentage (81%) of advisories were rated as acceptable after the subject matter experts used the tool's user interface to make route modifications that accounted for relevant operational factors not considered by the tool. The workload associated with using the tool, as measured by the NASA Task Load Index, was quite low (1.1 on a scale of 0 to 10). The results of this evaluation make a good case for human-automation teaming to design operationally valid weather re-routes for delay recovery.

Traffic Flow Management↗
DOE OSTI2015

A Comprehensive Validation Approach Using The RAVEN Code

The RAVEN computer code , developed at the Idaho National Laboratory, is a generic software framework to perform parametric and probabilistic analysis based on the response of complex system codes. RAVEN is a multi-purpose probabilistic and uncertainty quantification platform, capable to communicate with any system code. A natural extension of the RAVEN capabilities is the imple- mentation of an integrated validation methodology, involving several different metrics, that represent an evolution of the methods currently used in the field. The state-of-art vali- dation approaches use neither exploration of the input space through sampling strategies, nor a comprehensive variety of metrics needed to interpret the code responses, with respect experimental data. The RAVEN code allows to address both these lacks. In the following sections, the employed methodology, and its application to the newer developed thermal-hydraulic code RELAP-7, is reported.The validation approach has been applied on an integral effect experiment, representing natu- ral circulation, based on the activities performed by EG&G Idaho. Four different experiment configurations have been considered and nodalized.

PRA↗
DOE OSTI2022

A Zika virus mutation enhances transmission potential and confers escape from protective dengue virus immunity

Zika virus (ZIKV) and dengue virus (DENV) are arthropod-borne pathogenic flaviviruses that co-circulate in many countries. To understand some of the pressures that influence ZIKV evolution, we mimic the natural transmission cycle by repeating serial passaging of ZIKV through cultured mosquito cells and either DENV-naive or DENV-immune mice. Compared with wild-type ZIKV, the strains passaged under both conditions exhibit increased pathogenesis in DENV-immune mice. Application of reverse genetics identifies an isoleucine-to-valine mutation (I39V) in the NS2B proteins of both passaged strains that confers enhanced fitness and escape from pre-existing DENV immunity. Introduction of I39V or I39T, a naturally occurring homologous mutation detected in recent ZIKV isolates, increases the replication of wild-type ZIKV in human neuronal precursor cells and laboratory-raised mosquitoes. Our data indicate that ZIKV strains with enhanced transmissibility and pathogenicity can emerge in DENV-naive or -immune settings, and that NS2B-I39 mutants may represent ZIKV variants of interest.

59 BASIC BIOLOGICAL SCIENCES↗