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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 307 records · Page 17
All sourcesNASA NTRSDOE OSTI
NASA NTRS2016

End-of-Discharge and End-of-Life Prediction in Lithium-Ion Batteries with Electrochemistry-Based Aging Models

As batteries become increasingly prevalent in complex systems such as aircraft and electric cars, monitoring and predicting battery state of charge and state of health becomes critical. In order to accurately predict the remaining battery power to support system operations for informed operational decision-making, age-dependent changes in dynamics must be accounted for. Using an electrochemistry-based model, we investigate how key parameters of the battery change as aging occurs, and develop models to describe aging through these key parameters. Using these models, we demonstrate how we can (i) accurately predict end-of-discharge for aged batteries, and (ii) predict the end-of-life of a battery as a function of anticipated usage. The approach is validated through an experimental set of randomized discharge profiles.

batteries↗
NASA NTRS2018

Isochronal Age-mass Discrepancy of Young Stars: SCExAO/CHARIS Integral Field Spectroscopy of the HIP 79124 Triple System

We present SCExAO/CHARIS 1.1-2.4 μm integral field direct spectroscopy of the young HIP 79124 triple system. HIP 79124 is a member of the Scorpius-Centaurus association, consisting of an A0V primary with two low-mass companions at a projected separation of < 1″. Thanks to the high quality wavefront corrections provided by SCExAO, both companions are decisively detected without the employment of any PSF-subtraction algorithm to eliminate quasi-static noise. The spectrum of the outer C object is very well matched by Upper Scorpius M4 ± 0.5 standard spectra, with a T(eff) = 2945 ± 100 K and a mass of ∼350 M(Jup). HIP 79124 B is detected at a separation of only 180 mas in a highly-correlated noise regime, and it falls in the spectral range M6 ± 0.5 with T(eff) = 2840 ± 190 K and ∼100 M(Jup). Previous studies of stellar populations in Sco-Cen have highlighted a discrepancy in isochronal ages between the lower-mass and higher-mass populations. This could be explained either by an age spread in the region, or by conventional isochronal models failing to reproduce the evolution of low-mass stars. The HIP 79124 system should be coeval, and therefore it provides an ideal laboratory to test these scenarios. We place the three components in a color-magnitude diagram and find that the models predict a younger age for the two low-mass companions (∼3 Myr) than for the primary star (∼6 Myr). These results imply that the omission of magnetic effects in conventional isochronal models inhibit them from reproducing early low-mass stellar evolution, which is further supported by the fact that new models that include such effects provide more consistent ages in the HIP 79124 system.

Ruben Asensio-Torres↗
NASA NTRS2020

Precise Radiometric Age Establishes Yarrabubba, Western Australia, as Earth's Oldest Recognised Meteorite Impact Structure

The ~70 km-diameter Yarrabubba impact structure in Western Australia is regarded as among Earth’s oldest, but has hitherto lacked precise age constraints. Here we present U-Pb ages for impact21 driven shock recrystallised accessory minerals. Shock-recrystallised monazite yields a precise impact age of 2229 ± 5 Ma, coeval with shock-reset zircon. This result establishes Yarrabubba as the oldest recognized meteorite impact structure on Earth, extending the terrestrial cratering record back >200 million years. The age of Yarrabubba coincides, within uncertainty, with temporal constraint for the youngest Palaeoproterozoic glacial deposits, the Rietfontein diamictite in South Africa. Numerical impact simulations indicate that a 70 km-diameter crater into a continental glacier could release between 8.7x1013 to 5.0x1015 kg of H2O vapour instantaneously into the atmosphere. These results provide new estimates of impact-produced H2O vapour abundances for models investigating termination of the Paleoproterozoic glaciations, and highlight the possible role of impact cratering in modifying Earth’s climate.

Impact cratering↗
NASA NTRS2020

Billion-year exposure ages in Gale crater (Mars) indicate Mount Sharp formed before the Amazonian period

The erosion rates and mechanisms operating on Mount Sharp in Gale crater, Mars were assessed via experiments performed by the SAM instrument to determine the cosmogenic noble gas contents of Murray mudstone formation samples Mojave 2 and Quela. Previous measurements of samples from the Aeolis Palus depression between Mount Sharp and the north rim of Gale crater indicate that scarp retreat-generated surfaces formed within the last 100 Ma. In contrast, Mojave 2 yielded exposure ages of 1,320±240 (3He), 910±420 (21Ne), and 310±60 Ma (36Ar). Quela gave a 3He age of 1,460±200 Ma; 21Ne and 36Ar from this sample could not be quantified due to isobaric interferences. The discordant and young 36Ar exposure age in Mojave 2 is likely the result of interaction with water which dissolved the chlorine-bearing host phases of this nuclide. The most probable exposure scenario is that both Mojave 2 and Quela have been at the surface for the most recent ∼1 Ga after the overlying few meters of rock were removed in a geologically rapid exhumation episode. Based on local geomorphology, scarp retreat is the most likely mechanism for the exposure at these two sites. The exposure ages measured throughout Curiosity’s traverse indicate that the net removal of rock has proceeded more recently on Aeolis Palus than on the lower slopes of Mount Sharp. The implied differential erosion rate is insufficient to explain how Mount Sharp formed, even over billions of years. Instead, given that the surfaces on Mount Sharp have existed for >1 Ga, the mountain must have formed early, likely during the Hesperian. This study provides direct quantitative support for inferences based on crater counts that Mount Sharp had eroded to close to its current form before onset of the Amazonian.

Peter E. Martin↗
NASA NTRSDate not supplied

Age Estimates for Permanently Shadowed Craters in the VIPER Mission Area Based On Their Topography

A primary objective of the VIPER [1] mission is to characterize the distribution and physical state of volatiles at the lunar poles, including within permanently shadowed regions (PSRs) where water ice has been inferred to be stable [e.g.. 2,3]. A mission area for VIPER has been defined that enables this scientific objective near Nobile crater (Fig. 1)[4]. This location enables a traverse that can both meet VIPER’s engineering constraints (Earth-direct communication, adequate power, etc.)as well as accomplish the planned scientific exploration. In this abstract, we describe observations of crater topography that provide insight into the age of several craters that host PSRs within the planned VIPER mission area. The role that the age of PSRs plays in controlling the presence or absence of polar volatiles is of substantial interest for discerning volatile history [e.g., 5-7]. The physical state, depth distribution, and spatial distribution of volatile deposits may also vary as a function of PSR age due to gardening and/or differing emplacement mechanisms [8]. Understanding the age of PSRs that VIPER may explore is thus a useful goal.

C I Fassett↗
NASA NTRS2023

Dispersion and Aging of Volcanic Aerosols after the La Soufriere Eruption in April 2021

Volcanic aerosols change the atmospheric composition and thereby affect weather and climate. Aerosol dynamic processes such as nucleation, condensation, and coagulation modify the shape, size, and mass of aerosol particles, which influence their atmospheric lifetime and radiative properties. Nevertheless, most models omit these processes for ash particles. In this work, we explore the ash aerosol aging and sulfate production during the first 4 days following the 2021 La Soufrière (St. Vincent) eruption with the ICON-ART model (ICOsahedral Nonhydrostatic model with Aerosol and Reactive Trace gases). Online coupling of ICON-ART with a one-dimensional volcanic plume model calculates volcanic emission, which makes it possible to resolve the different eruption phases of the noncontinuous La Soufrière eruption. We compared our simulated aerosol distribution and composition with observations from the Cloud-Aerosol Lidar with Orthogonal Polarization (CALIOP) instrument, the Multiangle Imaging SpectroRadiometer (MISR) Research Aerosol (RA) Algorithm, and the Barbados Cloud Observatory (BCO). We show that online coupling is essential to adequately model the emissions and plume development close to the volcano. The modeled aerosol aging is in very good agreement with observations from MISR near the emission source and with CALIOP at larger distances. Furthermore, particle aging occurs faster in the troposphere than in the stratosphere due to the availability of water vapor and OH, but a layer of coated ash appears at the plume top due to faster oxidation of SO2 and lofting by aerosol-radiation interaction. This paper gives the first direct comparison of aerosol aging in volcanic eruption plumes between simulations and observations

volcanic aerosols↗
NASA NTRS1999

Lamb wave characterization of the effects of long-term thermal-mechanical aging on composite stiffness

Lamb waves offer a promising method of evaluating damage in composite materials. The Lamb wave velocity is directly related to the material parameters, so an effective tool exists to monitor damage in composites by measuring the velocity of these waves. The Lamb Wave Imager (LWI) uses a pulse/receive technique that excites an antisymmetric Lamb mode and measures the time-of-flight over a wide frequency range. Given the material density and plate thickness, the bending and out-of-plane shear stiffnesses are calculated from a reconstruction of the dispersion curve. In this study, the time-of-flight as well as the elastic stiffnesses D11, D22, A44, and A55 for composite samples which have undergone combined thermal and mechanical aging are obtained. The samples examined include a baseline specimen with 0 cycles, specimens which have been aged 2350 and 3530 cycles at high strain levels, and one specimen aged 3530 cycles at low strain levels.

Aircraft↗
NASA NTRS1999

Circadian regulation of human sleep and age-related changes in its timing, consolidation and EEG characteristics

The light-entrainable circadian pacemaker located in the suprachiasmatic nucleus of the hypothalamus regulates the timing and consolidation of sleep by generating a paradoxical rhythm of sleep propensity; the circadian drive for wakefulness peaks at the end of the day spent awake, ie close to the onset of melatonin secretion at 21.00-22.00 h and the circadian drive for sleep crests shortly before habitual waking-up time. With advancing age, ie after early adulthood, sleep consolidation declines, and time of awakening and the rhythms of body temperature, plasma melatonin and cortisol shift to an earlier clock hour. The variability of the phase relationship between the sleep-wake cycle and circadian rhythms increases, and in old age sleep is more susceptible to internal arousing stimuli associated with circadian misalignment. The propensity to awaken from sleep advances relative to the body temperature nadir in older people, a change that is opposite to the phase delay of awakening relative to internal circadian rhythms associated with morningness in young people. Age-related changes do not appear to be associated with a shortening of the circadian period or a reduction of the circadian drive for wake maintenance. These changes may be related to changes in the sleep process itself, such as reductions in slow-wave sleep and sleep spindles as well as a reduced strength of the circadian signal promoting sleep in the early morning hours. Putative mediators and modulators of circadian sleep regulation are discussed.

Review, Tutorial↗
NASA NTRS2013

NWA 7034 Martian Breccia: Disturbed Rb-Sr Systematics, Preliminary Is Approximately 4.4 Ga Sm-Nd Age

Agee et al. [1] reported a Rb-Sr age of 2.089 [plus or minus] 0.081 Ga for the unique Martian meteoritic breccia NWA 7034 making it the oldest Martian basalt, dating to the early Am-azonian epoch [2] of Martian geologic history. We have attempt-ed to confirm this exciting result. Our new Rb-Sr analyses show the Rb-Sr isotopic system to be disturbed, but preliminary Sm-Nd data suggest an even older age of approximately 4.4 Ga for at least some brec-cia components.

Nyquist, L. E.↗
NASA NTRS2018

Quantifying the Effect of Mixing on the Mean Age of Air in CCMVal-2 and CCMI-1 Models

The stratospheric age of air (AoA) is a useful measure of the overall capabilities of a general circulation model (GCM) to simulate stratospheric transport. Previous studies have reported a large spread in the simulation of AoA by GCMs and coupled chemistry-climate models (CCMs). Compared to observational estimates, simulated AoA is mostly too low. Here we attempt to untangle the processes that lead to the AoA differences between the models and between models and observations. AoA is influenced by both mean transport by the residual circulation and two-way mixing; we quantify the effects of these processes using data from the CCM inter-comparison projects CCMVal-2 (Chemistry-Climate Model Validation Activity 2) and CCMI-1 (Chemistry-Climate Model Initiative, phase 1). Transport along the residual circulation is measured by the residual circulation transit time (RCTT). We interpret the difference between AoA and RCTT as additional aging by mixing. Aging by mixing thus includes mixing on both the resolved and subgrid scale. We find that the spread in AoA between the models is primarily caused by differences in the effects of mixing and only to some extent by differences in residual circulation strength. These effects are quantified by the mixing efficiency, a measure of the relative increase in AoA by mixing. The mixing efficiency varies strongly between the models from 0.24 to 1.02. We show that the mixing efficiency is not only controlled by horizontal mixing, but by vertical mixing and vertical diffusion as well. Possible causes for the differences in the models' mixing efficiencies are discussed. Differences in subgrid-scale mixing (including differences in advection schemes and model resolutions) likely contribute to the differences in mixing efficiency. However, differences in the relative contribution of resolved versus parameterized wave forcing do not appear to be related to differences in mixing efficiency or AoA.

CCMI↗
NASA NTRS2018

CDKN1a/p21 Plays a Critical Role in Suppressing Stem Cell Regenerative Potential During Aging

Unloading during spaceflight is known to adversely affect mammalian physiology. Mechanical stimulation is required for repair and regeneration by stem cell lineages to maintain tissue health and mass. CDKN1a/p21 functions as a potent cell cycle arrest molecule and we previously found that CDKN1a/p21 was overexpressed in mouse bone during 15-days of spaceflight on STS-131 and localized to osteoprecursor cells in the femur. Therefore, we hypothesized that altered expression of CDKN1a/p21 leads to an arrest of bone formation during spaceflight in response to altered load. To study CDKN1a/p21 and its role in stem cell-based tissue regeneration, we use a CDKN1a/p21 knockout (KO) mouse to investigate the impact on bone structure, osteoprogenitor proliferation, and mineralized nodule formation. We have shown that bone marrow stem cells isolated from juvenile (11-week-old) and skeletally mature (18-week-old) KO mice have an increased bone formation potential as evidenced by increased proliferation and mineralization rates. In addition, we have shown that juvenile KO mice display significantly increased bone volume fraction (BV/TV) relative to wildtype (WT) mice, but not in skeletally mature KO mice, indicating increased resorption and bone turnover in adult mice. To more closely examine age differences in the KO mouse, we will study a wider spectrum of mice ranging from 4 weeks to 12 months in age. To do this, we will analyze differences in bone morphometric parameters using MicroCT and osteoblastogenesis assays. The pelvis, femur, and tibia are key in distributing weight and we expect to see altered remodeling and stem cell potential with age. In combination with histomorphometry, these results will help elucidate the complex mechanisms underlying bone tissue maintenance and stem cell regeneration.

stem cells↗
NASA NTRS2022

Estimation of Fire-induced CO Plume Age from NAST-I During the FIREX-AQ Field Campaign

Ultra-spectrally resolved infrared measurements from aircraft and space-based observations contain information about tropospheric carbon monoxide (CO) and ozone (O3), as well as other trace species. A methodology for retrieving these tropospheric trace species from such remotely sensed spectral data has been developed and validated for the National Airborne Sounder Testbed-Interferometer (NAST–I). The Fire Influence on Regional to Global Environments and Air Quality (FIREX-AQ) field campaign was conducted during August 2019 to investigate the impact of wildfire and biomass smoke on air quality and weather in the continental United States. NAST–I CO and O3 measurements from the recent FIREX-AQ field campaign are presented and used to estimate wildfire plume age. Results show enhanced levels of CO in the evolving plume as it is transported away from the fire ground site, and its plume age is associated with the plume distance in both the vertical and horizontal directions from the wildfire location. These results are enabled by the moderate-vertical and high-horizontal resolution obtained from the NAST–I IR spectrometer onboard the NASA ER-2 aircraft. This study advances our knowledge of fire-induced plumes with their evolution and age characterized in three-dimensional space using information from NAST–I retrieved CO and O3 and relative changes in their concentrations.

plume age↗
NASA NTRS1972

Interactions between creep, fatigue, and strain-aging in two refractory metal alloys.

The application of low-amplitude, high-frequency fatigue vibrations during creep testing of two strain-aging refractory alloys (molybdenum-base TZC and tantalum-base T-111) significantly reduced the creep strength of these materials. This strength reduction caused dramatic increases in both the first-stage creep strain and the second-stage creep rate. The magnitude of the creep rate acceleration varied directly with both frequency and A ratio (ratio of alternating to mean stress), and also varied with temperature, being greatest in the range where the strain-aging phenomenon was most prominent. It was concluded that the creep rate acceleration resulted from a negative strain rate sensitivity which is associated with the strain-aging phenomenon in these materials. (A negative rate sensitivity causes flow stress to decrease with increasing strain rate, instead of increasing as in normal materials.)

Sheffler, K. D.↗
NASA NTRS1972

Technique for rapid determination of relative ages of lunar areas from orbital photography.

Development of a technique for determining relative ages of regions of the lunar surface from orbital photography using a model of small-impact erosion. The erosion model relates the shape of a crater to the integrated flux of debris that has impacted the surface since that crater was fresh. The shape of the most modified crater of a particular diameter is thereby related to the relative age of the surface. Application of this analysis to orbital photography reveals that the major mare units vary in the accumulation of impacts by more than a factor of 3. Comparison of these data with crystallization ages determined from samples collected during the Apollo 11 and 12 missions indicates that the impact fluxes were decreasing during the stages of mare formation. An exponentially decaying flux for the last 3.5 b.y. with a half-life of 0.6 to 1.4 b.y. is compatible with the data.

Soderblom, L. A.↗
NASA NTRS1972

Gas retention and cosmic-ray exposure ages of a basalt fragment from Mare Fecunditatis.

The Ar40-Ar39 gas retention age and the Ar38-Ar37 cosmic ray exposure age have been determined on a total rock sample of the basalt fragment B-1 returned from Mare Fecunditatis by the Luna 16 mission. This sample shows a large low-temperature loss of radiogenic Ar40 but defines a reasonably good high-temperature plateau at 3.45 plus or minus 0.04 b.y. This is presumed to identify the period of igneous activity in Mare Fecunditatis. This activity is found to be later than that in the area of Mare Tranquilitatis, but earlier than that in the area of Oceanus Procellarum and Mare Imbrium. The cosmic-ray exposure age was found to be 475 m.y.

Huneke, J. C.↗
NASA NTRS1972

Terrestrial age of nineteen stony meteorites derived from their radiocarbon content.

Approximately 10 g of meteorite samples were analyzed. The results show that the average age of the investigated stony meteorites is 5200 yr. The set of finds used for the investigation was a more or less random selection of specimens from collections. The age value found may, therefore, well represent the average terrestrial age of finds of ordinary chondrites in the western U.S. Attention is drawn to the fact that the specimens examined were all from a part of the world with a fairly low rainfall.

Boeckl, R.↗
NASA NTRS1971

Age of an Apollo 15 mare basalt - Lunar crust and mantle evolution.

An internal Rb-Sr isochron for the large basalt boulder 15555 returned from the edge of Hadley rille by the Apollo 15 mission yields an age 3.32 (plus or minus 0.06) b.y. and an initial Sr-88/Sr-86, I = 0.69934 plus or minus 5. This age and I value fall well within the range obtained for the Apollo 12 basalts from the Ocean of Storms and may indicate that extensive lava flows occurred at 3.3 b.y. over widespread areas of the moon. The Sr composition of the anorthosite 15415 is as low as that of plagioclase extracted from the Apollo 11 low K rocks. The initial Sr composition of 15415 for an assumed age of 3.3 to 4.6 b.y. is extremely primitive and provides further evidence for an extremely short formation interval of a nonchondritic moon with respect to an origin in time defined by BABI.

Wasserburg, G. J.↗
NASA NTRS1973

Noble gas concentrations and cosmic ray exposure ages of eight recently fallen chondrites

Abundances and isotopic compositions of He, Ne, Ar, and Xe have been measured in eight recently fallen chondrites. Ratios of concentrations of cosmic ray-produced He-3, Ne-21, Ne-22, and Ar-38 indicate that all eight samples experienced less than average cosmic ray shielding. He-3 and Ne-21 exposure ages were calculated using shielding corrected chondritic production rates and the measured Ne-22/Ne-21. Exposure ages calculated from Na-22/Ne-22 and Al-26/Ne-21 ratios and constant relative production rates show a bias between the two ages due to variations in Na-22/Al-26. Arguments are presented that this bias is due to irradiation hardness differences, and therefore the use of constant values for both the Na-22/Ne-22 and Al-26/Ne-21 production ratios is not permitted.

Bogard, D. D.↗