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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 559 records · Page 31
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DOE OSTI2025

Long Range Plan: Dense matter theory for heavy-ion collisions and neutron stars

Since the release of the 2015 Long Range Plan in Nuclear Physics, major events have occurred that reshaped our understanding of quantum chromodynamics (QCD) and nuclear matter at large densities, in and out of equilibrium. The US nuclear community has an opportunity to capitalize on advances in astrophysical observations and nuclear experiments and engage in an interdisciplinary effort in the theory of dense baryonic matter that connects low- and high-energy nuclear physics, astrophysics, gravitational waves physics, and data science. This is a white paper prepared by a group of nuclear physicists during the 2023 LRP process.

Lovato, Alessandro↗
DOE OSTI2024

Systematic and objective evaluation of Earth system models: PCMDI Metrics Package (PMP) version 3

Systematic, routine, and comprehensive evaluation of Earth system models (ESMs) facilitates benchmarking improvement across model generations and identifying the strengths and weaknesses of different model configurations. By gauging the consistency between models and observations, this endeavor is becoming increasingly necessary to objectively synthesize the thousands of simulations contributed to the Coupled Model Intercomparison Project (CMIP) to date. The Program for Climate Model Diagnosis and Intercomparison (PCMDI) Metrics Package (PMP) is an open-source Python software package that provides quick-look objective comparisons of ESMs with one another and with observations. The comparisons include metrics of large- to global-scale climatologies, tropical inter-annual and intra-seasonal variability modes such as the El Niño–Southern Oscillation (ENSO) and Madden–Julian Oscillation (MJO), extratropical modes of variability, regional monsoons, cloud radiative feedbacks, and high-frequency characteristics of simulated precipitation, including its extremes. The PMP comparison results are produced using all model simulations contributed to CMIP6 and earlier CMIP phases. An important objective of the PMP is to document the performance of ESMs participating in the recent phases of CMIP, together with providing version-controlled information for all datasets, software packages, and analysis codes being used in the evaluation process. Among other purposes, this also enables modeling groups to assess performance changes during the ESM development cycle in the context of the error distribution of the multi-model ensemble. Quantitative model evaluation provided by the PMP can assist modelers in their development priorities. In this paper, we provide an overview of the PMP, including its latest capabilities, and discuss its future direction.

54 ENVIRONMENTAL SCIENCES↗
NASA NTRS1975

Conservation and the industry sector

The following six highly energy intensive industries were studied as targets of energy conservation opportunity: food and kindred products, paper and allied products, chemicals and allied products, petroleum and coal products, stone, glass and clay products, and primary manufacturing. After studying conservation actions within each industry the actions were grouped under three broad categories: increased combustion efficiency, process improvement, and good housekeeping. Some of the results were: (1) approximately 2.18 quads could be saved in 1980 and 2.57 quads in 1985 by installing cogenerative facilities in 50% of the industries, (2) regenerative air-preheaters could result in a 10-15% increase in furnace efficiency representing a 15-25% fuel savings (2.3 to 3.9 quads in 1980 and 2.7 to 4.5 quads in 1985), (3) several major industries have potential for energy savings by recycling-aluminum (0.2 quads), steel (1 quad), glass (0.006 quads), paper and cement (0.08 quads).

Source record↗
NASA NTRS1978

Ion microprobe analyses of aluminous lunar glasses - A test of the 'rock type' hypothesis

Previous soil survey investigations found that there are natural groupings of glass compositions in lunar soils and that the average major element composition of some of these groupings is the same at widely separated lunar landing sites. This led soil survey enthusiasts to promote the hypothesis that the average composition of glass groupings represents the composition of primary lunar 'rock types'. In this investigation the trace element composition of numerous aluminous glass particles was determined by the ion microprobe method as a test of the above mentioned 'rock type' hypothesis. It was found that within any grouping of aluminous lunar glasses by major element content, there is considerable scatter in the refractory trace element content. In addition, aluminous glasses grouped by major elements were found to have different average trace element contents at different sites (Apollo 15, 16 and Luna 20). This evidence argues that natural groupings in glass compositions are determined by regolith processes and may not represent the composition of primary lunar 'rock types'.

Meyer, C., Jr.↗
NASA NTRS1980

The opportunities offered by SCADM for the study of surface phenomena related to interior structure and dynamics

The physical processes to be probed by experiments may be grouped as large scale flows, oscillations, and chromospheric/coronal diagnostics. While the fundamental concerns and observational equipments are similar within each class, different investigations may tell different things about the Sun. Observational requirements are listed for experiments to study (1) plasma-magnetic field interactions; (2) interior structure via oscillations; (3) chromospheric and coronal tracers; (4) rotation, meridional flows, and giant cells; (5) the depth dependence of rotation; (6) EUV luminosity; (7) intensity fluctuations and tracers; and (8) diameter oscillations, the effects of noise and timestring on experiment results are assessed.

Brown, T. M.↗
NASA NTRS1981

Susceptibility of materials processing experiments to low-level accelerations

The types of material processing experiments being considered for shuttle can be grouped into four categories: (1) contained solidification experiment; (2) quasicontainerless experiments; (3) containerless experiments; and (4) fluids experiments. Low level steady acceleration, compensated and uncompensated transient accelerations, and rotation induced flow factors that must be considered in the acceleration environment of a space vehicle whose importance depends on the type of experiment being performed. Some control of these factors may be exercised by the location and orientation of the experiment relative to shuttle and by the orbit vehicle attitude chosen for mission. The effects of the various residual accelerations can have serious consequence to the control of the experiment and must be factored into the design and operation of the apparatus.

Naumann, R. J.↗
NASA NTRS1990

Polyimides Containing Carbonyl And Ether Connecting Groups

Polyimides of new class made from chemical reactions of aromatic dianhydrides with novel aromatic diamines in which carbonyl and ether groups connect aromatic rings. New polyimides melt-processable, strong, resistant to impacts, and resistant to solvents and other chemicals. Useful as adhesives, coatings, films, membranes, and composite matrices.

Hergenrother, Paul M.↗
NASA NTRS1989

Meteoritic basalts

The objectives were to: explain the abundances of siderophile elements in the SNC meteorite suite, of putative Martian origin; discover the magmatic origins and possibly magma compositions behind the Nakhla meteorite, one of the SNC meteorites; and a re-evaluation of the petrology of Angra dos Reis, a unique meteorite linked to the earliest planetary bodies of the solar nebula. A re-evaluation of its petrography showed that the accepted scenario for its origin, as a cumulate igneous rock, was not consistent with the meteorite's textures (Treiman). More likely is that the meteorite represents a prophyritic igneous rock, originally with magma dominant. Studies of the Nakhla meteorite, of possible Martian origin, although difficult, were successful. It became necessary to reject the basic categorization of Nakhla: that is was a cumulate igneous rock. Detailed studies of the chemical zoning of Nakhlas' minerals, coupled with the failure of experimental studies to yield expected results, forced the conclusion that Nakhla is not a cumulate rock in the usual sense: a rock composed of igneous crystals and intercrystal magma. Study of the siderophile element abundances in the SNC meteorite groups involved trying to find reasonable core formation processes and parameters that would reproduce the observed abundances. Modelling was successful, and delimited a range of models which overlap with those reasonable from geophysical constraints.

Treiman, Allan H.↗
NASA NTRS1990

Positronium formation in Ss state in e+-Li scattering

There are ample theoretical reasons to investigate positron-alkali atom scattering. Moreover, recent measurement on positron-alkali atom system by a Detroit group has renewed much interest in investigating these processes. Positronium (Ps) formation in excited 2s state in positron-Li scattering at intermediate and high energies were studied including second order effects following Basu and Ghosh.

Sarkar, K. P.↗
NASA NTRS1990

Implementation of Sensor and Control Designs for Bioregenerative Systems

The goal of the Spring 1990 EGM 4001 Design class was to design, fabricate, and test sensors and control systems for a closed loop life support system (CLLSS). The designs investigated were to contribute to the development of NASA's Controlled Ecological Life Support System (CELSS) at Kennedy Space Center (KSC). Designs included a seed moisture content sensor, a porous medium wetness sensor, a plant health sensor, and a neural network control system. The seed group focused on the design and implementation of a sensor that could detect the moisture content of a seed batch. The porous medium wetness group concentrated on the development of a sensor to monitor the amount of nutrient solution within a porous plate incorporating either infrared reflectance or thermal conductance properties. The plant health group examined the possibility of remotely monitoring the health of the plants within the Biomass Production Chamber (BPC) using infrared reflectance properties. Finally, the neural network group concentrated on the ability to use parallel processing in order to control a robot arm and analyze the data from the health sensor to detect regions of a plant.

Rodriguez, Pedro R.↗
NASA NTRS1992

Spectral identification of chemisorbed CO2 and application to Mars analog materials

The goal of this work is to identify the spectral signature of chemisorbed CO2, to test the efficacy of carbonate formation on Mars-analog materials via CO2 chemisorption, and to identify the surface-chemical characteristics of good chemisorbents, with the intent of assessing the possible geochemical importance of CO2 chemisorption as a quasipermanent CO2 sink in the Martian environment. Our approach is to search for infrared spectral bands that result from chemisorption of CO2 molecules onto chemical reagents and Mars-analog materials, and to identify the salient differences in adsorbents that favor strong, permanent CO2 chemisorption. The total amount of CO2 in the early Martian atmosphere, and consequent surface temperatures, are unknown. A CO2 greenhouse may not have been an adequate mechanism under any circumstances; however, it if were, then most of that CO2 must still be in the near-surface environment; no escape mechanism that could remove it after the decline of channeling has been identified. The only plausible reservoir is carbonate, and there are various remote sensing techniques that can be used to search for it. We are investigating CO2 chemisorption as a permanent CO2 sink, and to aid in interpretation of remotely sensed IR spectra of Mars. A common effect reported in CO2 adsorption studies is the formation of a layer of carbonate or bicarbonate anions on adsorbents that have OH- groups available on their surfaces. Inorganic hydroxyls occur on phyllosilicates, amorphous silicates, metal oxides and hydroxides; it is the most abundant and reactive surface functional group on the surfaces of terrestrial silicates. The process responsible for the reaction is chemisorption. Chemisorption is distinguished from physical adsorption in that there is a transfer of electrons between species, and the formation of a chemical bond. The heat of chemisorption is typically of the same order as heats of chemical reaction (i.e., a few hundred to a few thousand kJ/mole), as opposed to heats of physical adsorption (a few kJ per mole). Chemisorption is an activated process that is promoted by an increase in temperature - quite the opposite of physical adsorption. Chemisorption is not reversible in the sense that physical adsorption is.

Zent, A. P.↗
NASA NTRS1993

Genesis of the IIICD iron meteorites - Evidence from silicate-bearing inclusions

Our studies of the silicate-bearing inclusions in the IIICD iron meteorites Maltahohe, Carlton, and Dayton suggest that their mineralogy and mineral compositions are related to the composition of the metal in the host meteorites. An inclusion in the low-Ni Maltahohe is similar in mineralogy to those in IAB irons, which contain olivine, pyroxene, plagioclase, graphite, and troilite. With increasing Ni concentration of the metal, silicate inclusions become poorer in graphite, richer in phosphates, and the phosphate and silicate assemblages become more complex. Dayton contains pyroxene, plagioclase, SiO2, brianite, panethite, and whitlockite, without graphite. In addition, mafic silicates become more FeO-rich with increasing Ni concentration of the hosts. In contrast, silicates in IAB irons show no such correlation with host Ni concentration, nor do they have the complex mineral assemblages of Dayton. These trends in inclusion composition and mineralogy in IIICD iron meteorites have been established by reactions between the S-rich metallic magma and the silicates, but the physical setting is uncertain. Of the two processes invoked by other authors to account for groups IAB and IIICD, fractional crystallization of S-rich cores and impact generation of melt pools, we prefer core crystallization. We suggest that the solidification of the IIICD core may have been very complex, involving fractional crystallization, nucleation effects and, possibly, liquid immiscibility.

Mccoy, Timothy J.↗
NASA NTRS1992

RICIS Symposium 1992: Mission and Safety Critical Systems Research and Applications

This conference deals with computer systems which control systems whose failure to operate correctly could produce the loss of life and or property, mission and safety critical systems. Topics covered are: the work of standards groups, computer systems design and architecture, software reliability, process control systems, knowledge based expert systems, and computer and telecommunication protocols.

Source record↗
NASA NTRS1996

Effects of Core Thickness and Fiber Orientation on Composite Beam Stiffness

This laboratory experiment is intended for students in an introductory polymer materials and processes course or engineering materials course. It can be conducted as an introduction to the hand lay-up process, with additional observations regarding the stiffness of the completed composite beams based on core thickness and fiber orientation. Students gain hands-on experience with the hand lay-up process by constructing glass/epoxy composite panels. Each lab group produces a panel with different core thickness or fiber orientation. The panels are then cut into strips and tested for flexural stiffness in a three-point bending fixture. Students plot deflection versus load data for composite beams with two different fiber orientations, two core thicknesses and one beam with laminate plies only (no core). The deflection plots highlight the effects of core thickness and fiber orientation on composite beam stiffness.

Hillsman, Vernon S.↗
NASA NTRS1999

MSFC Investigations of Beta Cloth Darkening Due to Ultraviolet Radiation Interactions

A common component of multi-layer insulation blankets is beta cloth, a woven fiberglass cloth impregnated with Teflon. It is planned for extensive use on the International Space Station (ISS). The Environmental Effects Group of the Marshall Space Flight Center Materials, Processing and Manufacturing Department has investigated the impact of atomic oxygen (AO) and ultraviolet (UV) radiation on the optical properties of plain and aluminized beta cloth, both in the laboratory and as part of long-duration flight experiments. These investigations indicate that beta cloth was susceptible to darkening in the presence of UV radiation, dependent on the additives used. The presence of AO countered some, if not all, of the UV degradation.

Kamenetzky, Rachel R.↗
NASA NTRS1999

A LIS Validation Study at the KSC-ER using LDAR and Field Mill Data

The chance of having the TRMM satellite pass over east central Florida when there is lightning over the NASA Kennedy Space Center (KSC) and USAF Eastern Range (ER) is small; however, such a condition did occur on September 21, 1998 (Day 264). Starting at about 20:40 GMT, the Lightning Imaging Sensor (LIS) reported 5 flashes during a 90 second interval that the KSC-ER was within the sensor field of view. Ground-based instrumentation, the Lightning Detection and Ranging (LDAR) system and a network of electric field mills (FM), detected 6 flashes in the same interval. In this paper, we will compare the times and locations of the optical pulses that were detected by LIS with the times and locations of RF sources (LDAR) and the charges that were deposited by the flash (FM network). We will show that LIS responded to all flashes that the LDAR and FM network detected; however, two discharges that were separated by less than 1 second in time and by about 10 km in space were grouped as one flash by the LIS data processing algorithm. In spite of the fact that all flashes occurred near the edge of the LIS field of view, the locations of the LIS events were consistent with both the LDAR and FM locations (the latter are usually within 1-2 kilometers of each other and often are co-located). Two of the 5 flashes reported by LIS were shifted north by about 8 km from the corresponding LDAR and FM locations. The LIS flash times tended to be after the first LDAR pulse was detected and before the last, and the integrated light signal (per LIS event) was surprisingly constant over the 5 flashes that were detected by LIS. In the future, we plan to study more correlated events and will try to determine whether and how the LIS light signal is related to the charge transfer in the flash and/or the number and spatial extent of RF sources.

Koshak, William J.↗
NASA NTRS1999

Comparison of Observed Beta Cloth Interactions with Simulated and Actual Space Environment

A common component of multilayer insulation blankets is beta cloth, a woven fiberglass cloth impregnated with Teflon(TM). It is planned for extensive use on the International Space Station. The Environmental Etl'ects Group of the Marshall Space Flight Center Materials, Processing, and Manufacturing Department has investigated the impact of atomic oxygen (AO) and ultraviolet (UV) radiation on the optical properties of plain and aluminized beta cloth. both in the laboratory and as part of long-duration flight experiments. These investigations indicate that beta cloth is susceptible to darkening in the presence of UV radiation, dependent on the additives used. AO interactions resulted in bleaching of the beta cloth.

Kamenetzy, R. R.↗