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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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All sourcesNASA NTRSDOE OSTI
NASA NTRSDate not supplied

The History of EVA Safety at NASA

With NASA’s past and current involvement in Human Space Exploration in low Earth orbit and on the Moon, in lunar orbit and on the surface in the near future, and interplanetary space and the surface of Mars in the coming decades, the safety of the crew during Extravehicular Activity (EVA) remains paramount. EVAs during human space flight will challenge the crew and Mission Control for not only maintenance and reliability tasks but also exploration activities during a mission. Outside of launch and landing, EVA is the most dangerous crewed operation during a mission, making proper safety measures essential. This paper will explore how EVA safety operations havebeen managed throughout NASA’s history during the Gemini, Apollo, and Space Shuttle programs, how it is currently being managed for the International Space Station Program, and how these methods are planned to be utilized for Exploration efforts for human space flight into the future. Understanding the theory and processes that led to the documented safety requirements in the past and present will give insight into how to manage Exploration operations in the future, and may lead to process improvement with the advancements of technology in work today.

EVA↗
NASA NTRS2022

A History of the NASA Planetary Astronomy Program: 1958-2022

For decades, the public has been enraptured by popular high-resolution images and data taken of our multicolored planets by space-based telescopes. However, at the time NASA was established in October 1958, there was limited astronomical interest in planetary science with ground-based telescopes. Instead, stellar astronomy dominated most of the observing time at facilities, as astrophysics was considered the forefront of astronomical research. Once NASA determined that it wanted launch planetary missions to explore the solar system in detail, it became obvious that there were not enough high-quality solar system observations to lay the foundation for these missions. Therefore, the NASA Planetary Astronomy program (PAST) was established to fund ground-based research on solar system objects. This research covers the history of this important but little-known NASA program, which not only provided necessary support for planetary missions but also was responsible for rejuvenating astronomer interest in solar system research.

NASA PAST Program↗
DOE OSTI2015

Forsterite dissolution rates in Mg‐sulfate‐rich Mars‐analog brines and implications of the aqueous history of Mars

Abstract High salinity brines, although rare on Earth's surface, may have been important in the geologic history of Mars. Increasing evidence suggests the importance of liquid brines in multiple locations on Mars. In order to interpret the effect of high ionic strength brines on olivine dissolution, which is widely present on Mars, 47 new batch reactor experiments combined with 35 results from a previous study conducted at 25°C from 1 < pH < 4 in magnesium sulfate, sodium sulfate, magnesium nitrate, and potassium nitrate solutions with ionic strengths as high as 12 m show that very high ionic strength brines have an inhibitory effect of forsterite dissolution rates. Multiple linear regression analysis of the data suggests that the inhibition in dissolution rates is due to decreased water activity at high ionic strengths. Regression models also show that m Mg up to 4 m and m SO4 up to 3 m have no effect on forsterite dissolution rates. The effect of decreasing dissolution rates with decreasing a H2O is consistent with the idea that water acts as a ligand that participates in the dissolution process. Less available water to participate in the dissolution reaction results in a slower dissolution rate. Multiple linear regression analysis of the data produces the rate equation . Forsterite in dilute solutions with a water activity of one dissolves twice as fast as those in brines with a water activity of 0.8.

Olsen, Amanda Albright↗
DOE OSTI2016

Standardization of chemical analytical techniques for pyrolysis bio-oil: history, challenges, and current status of methods

Here, we discuss the standardization of analytical techniques for pyrolysis bio-oils, including the current status of methods, and our opinions on future directions. First, the history of past standardization efforts is summarized, and both successful and unsuccessful validation of analytical techniques highlighted. The majority of analytical standardization studies to-date has tested only physical characterization techniques. In this paper, we present results from an international round robin on the validation of chemical characterization techniques for bio-oils. Techniques tested included acid number, carbonyl titrations using two different methods (one at room temperature and one at 80 °C), 31 P NMR for determination of hydroxyl groups, and a quantitative gas chromatography–mass spectrometry (GC-MS) method. Both carbonyl titration and acid number methods have yielded acceptable inter-laboratory variabilities. 31 P NMR produced acceptable results for aliphatic and phenolic hydroxyl groups, but not for carboxylic hydroxyl groups. As shown in previous round robins, GC-MS results were more variable. Reliable chemical characterization of bio-oils will enable upgrading research and allow for detailed comparisons of bio-oils produced at different facilities. Reliable analytics are also needed to enable an emerging bioenergy industry, as processing facilities often have different analytical needs and capabilities than research facilities. We feel that correlations in reliable characterizations of bio-oils will help strike a balance between research and industry, and will ultimately help to -determine metrics for bio-oil quality. Lastly, the standardization of additional analytical methods is needed, particularly for upgraded bio-oils.

09 BIOMASS FUELS↗
DOE OSTI2019

Does River Restoration Increase Fish Abundance and Survival or Concentrate Fish? The Effects of Project Scale, Location, and Fish Life History

Abstract Despite billions of dollars spent on various river restoration techniques, we still find ourselves debating whether habitat restoration increases fish abundance or concentrates fish. Based on the available literature, I discuss three important questions related specifically to the restoration of salmonid habitat: (1) “Does river restoration increase fish abundance or concentrate fish?”; (2) “Does river restoration increase fish survival or increase abundance?”; and (3) “Does the size or amount of river restoration influence fish response?” First, there is scant evidence to support the contention that river restoration leads to the concentration of fish at restoration projects. Second, the literature suggests that river restoration may lead to increased survival, increased abundance, or both. Third, recent studies have found little relationship between restoration project length and physical or biological response. The scientific literature does suggest that fish response to restoration varies greatly depending on the watershed template, location, and characteristics of the habitat restoration, and the life history of and limiting factors for a species. Thus, adequately determining whether changes in fish abundance observed in a restored area are due to increased movement, survival, or the amount of restoration will require detailed monitoring of these factors simultaneously.

Roni, Philip↗
DOE OSTI2020

Evolutionary history, potential intermediate animal host, and cross-species analyses of SARS-CoV-2

To investigate the evolutionary history of the recent outbreak of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in China, a total of 70 genomes of virus strains from China and elsewhere with sampling dates between 24 December 2019 and 3 February 2020 were analyzed. To explore the potential intermediate animal host of the SARS-CoV-2 virus, we reanalyzed virome data sets from pangolins and representative SARS-related coronaviruses isolates from bats, with particular attention paid to the spike glycoprotein gene. We performed phylogenetic, split network, transmission network, likelihood-mapping, and comparative analyses of the genomes. Additionally, based on Bayesian time-scaled phylogenetic analysis using the tip-dating method, we estimated the time to the most recent common ancestor and evolutionary rate of SARS-CoV-2, which ranged from 22 to 24 November 2019 and 1.19 to 1.31 × 10 -3 substitutions per site per year, respectively. Our results also revealed that the BetaCoV/bat/Yunnan/RaTG13/2013 virus was more similar to the SARS-CoV-2 virus than the coronavirus obtained from the two pangolin samples (SRR10168377 and SRR10168378). We also identified a unique peptide (PRRA) insertion in the human SARS-CoV-2 virus, which may be involved in the proteolytic cleavage of the spike protein by cellular proteases, and thus could impact host range and transmissibility. Interestingly, the coronavirus carried by pangolins did not have the RRAR motif. Therefore, we concluded that the human SARS-CoV-2 virus, which is responsible for the recent outbreak of COVID-19, did not come directly from pangolins.

59 BASIC BIOLOGICAL SCIENCES↗
DOE OSTI2020

Isopropanol dehydration reaction rate kinetics measurement using H 2 O time histories

H 2 O formation during thermal decomposition of isopropanol was measured behind reflected shock waves at temperatures ranging from 1127 to 1621 K at an average pressure of 1.42 atm using a laser absorption technique. Of the five modern chemical kinetics models used to compare the H 2 O time histories, the model from Li et al (Combust. Flame 2019;207:171-185) showed the best overall agreement. Sensitivity and rate of production analyses using the Li et al model (as well as those from AramcoMech 3.0, CRECK, and Togbe et al (Energy Fuel. 2011;25:676-683)) showed unimolecular dehydration of isopropanol, iC 3 H 7 OH ⇌ H 2 O + C 3 H 6 (R1), is nearly the sole reaction controlling H2O production at early times, allowing for an a priori measurement of the forward rate constant k 1 . The Arrhenius expression k1 (s –1 ) = 2.60 × 10 13 exp(-31 120 K/T) was determined to represent best the data from this study. According to the models and previous experimental investigations, the pressure investigated is well within the high-pressure limit (HPL) for this reaction. Additional, higher-pressure experiments also confirmed the HPL assumption. An uncertainty analysis was performed by varying secondary reactions within their uncertainties and examining their effect on the overall prediction, establishing an uncertainty within ±20% for all but the highest temperature cases, which have a maximum uncertainty of ±40%. Experiments conducted with a radical trapper, toluene, showed little influence from radical chemistry, suggesting this estimated uncertainty is fairly conservative. Experimental data from Heyne et al (Z Phys Chem. 2015;229:881-907) were found to be in good agreement with the rate measurements from this study and, therefore, a second Arrhenius expression, k 1 (s –1 ) = 2.11 × 10 13 exp(-30 820 K/T), was found to represent both datasets well. This second expression has a larger temperature range of 976-1621 K. Here the present study provides the first high-temperature data collected for this reaction, adding to the limited data available for isopropanol in the literature.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2020

Understanding Life History Diversity of a Wild Steelhead Population and Managing for Resiliency

Abstract Diversity in steelhead Oncorhynchus mykiss (anadromous Rainbow Trout) is often characterized by varying time spent in freshwater and saltwater environments. However, ontogenetic shifts are not often highlighted as an important diversity characteristic in salmonids. Larger water bodies can play a key role in population stability by buffering limited resources in smaller tributary systems. Based on freshwater and saltwater ages of adult steelhead in Fish Creek, Idaho, there were 12 different life history trajectories observed. Juvenile abundance varied from 12,083 (SE = 1,225.7) to 62,463 (SE = 1,753.8), with ages ranging from young of the year (age 0) to 4 years. Adult abundance fluctuated from 17 (SE < 0.1) to 499 (SE = 67.1), and total age of adults varied from 3 to 7 years. Diversity was most evident in juvenile movement and rearing strategies. We observed four types of movement and rearing pathways in which juveniles either directly migrated to the ocean from Fish Creek or resided for up to three winters in main-stem river habitat in the Clearwater River basin prior to ocean migration. Most juveniles emigrated in the fall at age 2, and most ocean-emigrating smolts were age 3. Subsequently, most juveniles resided for at least one additional winter period before ocean migration. Juvenile diversity was also reflected in adult ages; the mean proportion that spent 3 years in freshwater was 0.55 (SE = 0.03), and the mean proportion that spent 2 years in freshwater was 0.41 (SE = 0.03). Adult sex ratio was female biased (mean ± SE = 0.66 ± 0.02), with a higher proportion of females (0.89 ± 0.03) than males (0.65 ± 0.05) residing in the ocean for at least 2 years. Density-dependent mechanisms were evident in juvenile rearing habitat in Fish Creek for cohorts of high female abundance. Population productivity potentials can be met when tributary and main-stem rearing habitat can be utilized, and this will be essential in attaining recovery goals.

Dobos, Marika E.↗
DOE OSTI2012

Microstructure evolution during tensile loading histories of a polyurea

The evolution in the hard/soft domain microstructure of an elastomeric-like polyurea during different tensile loading histories was studied using in situ small- and wide-angle X-ray scattering (SAXS/WAXS). The nonlinear stress-strain behavior is initially stiff with a rollover yield to a more compliant response; unloading is highly nonlinear showing substantial hysteresis while also exhibiting significant recovery. Reloading reveals a substantially more compliant 'softened' behavior and dramatically reduced hysteresis. WAXS peaks monitor characteristic dimensions of regular features within the hard domains; the peak location remains unchanged with tensile deformation indicating no separation of the internal structure within a domain, but the peak intensity becomes anisotropic with deformation evolving in a reversible manner consistent with orientation due to stretch. The SAXS profiles provide information between major hard domains. SAXS peaks are found to shift with tensile loading in a relatively affine manner up to a tensile true strain of {approx}0.4, which, using a Bragg reduction to aid interpretation, reveals an axial increase and a transverse decrease in interdomain spacings; this evolution is reversible for strains less than {approx}0.4. Increasing axial strain beyond a true strain of {approx}0.4 is accompanied by a dramatic, progressive, and irreversible reduction in axial Bragg spacing, indicating a breakdown in the hard domain aggregate network structure. A four-point pattern is seen to develop during stretching. The breakdown in networked structure during a first load cycle gives a new structure for subsequent load cycles, which is seen to evolve in a reversible manner for strains less than or equal to the prior maximum strain. However, for strains exceeding the prior maximum strain excursion, additional breakdown is found. These SAXS results show that a breakdown in the hard domain aggregate network structure is a governing mechanism for the large dissipation (hysteresis) loops of the first load cycle and are also responsible for the softened reloading response. The absence of structure breakdown during subsequent load cycles corresponds to the substantially reduced hysteresis loops as well as the stable softened behavior. DMA data on pristine and previously deformed samples show a more compliant storage modulus in the predeformed sample, supporting the softened cyclic stress-strain data and the structural breakdown observed in the SAXS; the loss modulus was unchanged with deformation, which correlates with the lossy features measured in DMA with time-dependent viscosity rather than losses due to structural breakdown.

36 MATERIALS SCIENCE↗
DOE OSTI2026

Computationally inexpensive part-scale thermal history of additive friction-stir deposition

This study presents an analytical model for steady-state power generation and tool heat loss in additive friction-stir deposition (AFSD), developed to enable part-scale thermal simulation while remaining computationally inexpensive. The model predicts total generated power, yielding 3.7–4.7 kW across deposition temperature setpoints of 400–460 °C for the deposition of AA6061 with a Be-Cu tool. This corresponds to 90–95% of the reported spindle power. Tool heat loss is experimentally determined by calibrating a steady-state energy balance between the generated power, the substrate-deposition thermal gradient, and a temperature dependent tool heat loss term: q tool (T) = a + b (T - 400°C) with a = 2.7 x 10 6 Wm -2 and b = 9.5 x 10 3 Wm -2 K -1 . The calibration indicates that about 69% of the generated heat is conducted into the tool for this configuration, which is much higher than previously reported. The calibrated heat-source is implemented in finite element software (Adamantine) to simulate the transient thermal history of a 100 cm 3 representative build in 8 min on a standard desktop (at 0.635 mm build-height resolution). For the first three layers, the substrate temperatures between simulation and experiment are within 10% mean absolute percentage error. Sensitivity analysis indicates that uncertainties in average deposition temperature and deformation localization (stir-zone geometry, depth, and spatial dependance of strain-rate and flow stress) dominate model variance, motivating additional experimental verification.

Additive Friction-Stir Deposition↗
DOE OSTI2019

Natural history of percutaneous drainage of postoperative collection following colorectal surgery: in which patients can follow-up imaging be dispensed with before drain removal?

Introduction: Colorectal surgery is complicated by postoperative collections in up to 25% of cases depending on local conditions. The aim of this study was to identify predictive factors of success of percutaneous drainage of collections in order to avoid follow-up imaging. Patients and methods: All consecutive patients between January 2009 and December 2016, who had undergone elective or emergency colorectal surgery (colorectal surgery and appendectomy) complicated by a postoperative collection treated by percutaneous drainage with follow-up imaging prior to drain removal, were included in this single-center and retrospective study. The primary objective was to assess predictive factors of success of the first attempt of percutaneous drainage of collections. Secondary objectives were to describe the natural history of percutaneous drainage of postoperative collections after colorectal surgery and the overall success rate of percutaneous drainage. Results: Fifty-three patients underwent percutaneous drainage of a postoperative collection during the study period and were included in this study. Complete resolution of the collection was observed on the first follow-up radiological examination in 36 patients (58%). In multivariate analysis, post-appendectomy collections (OR = 3.19 (1.14–9.27), p = 0.002) and reduction of the leukocyte count (OR = 3.22 (1.28–8.1), p = 0.013) were significantly associated with success of percutaneous drainage. Conclusion: This is the first study to address that follow-up imaging prior to drain removal might not be necessary in patients undergoing drainage of post-appendectomy collections and/or with more than 30% reduction of the leukocyte count at the first follow-up examination.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2024

Stressful crystal histories recorded around melt inclusions in volcanic quartz

Abstract Magma ascent and eruption are driven by a set of internally and externally generated stresses that act upon the magma. We present microstructural maps around melt inclusions in quartz crystals from six large rhyolitic eruptions using synchrotron Laue X-ray microdiffraction to quantify elastic residual strain and stress. We measure plastic strain using average diffraction peak width and lattice misorientation, highlighting dislocations and subgrain boundaries. Quartz crystals across studied magma systems preserve similar and relatively small magnitudes of elastic residual stress (mean 53–135 MPa, median 46–116 MPa) in comparison to the strength of quartz (~ 10 GPa). However, the distribution of strain in the lattice around inclusions varies between samples. We hypothesize that dislocation and twin systems may be established during compaction of crystal-rich magma, which affects the magnitude and distribution of preserved elastic strains. Given the lack of stress-free haloes around faceted inclusions, we conclude that most residual strain and stress was imparted after inclusion faceting. Fragmentation may be one of the final strain events that superimposes stresses of ~ 100 MPa across all studied crystals. Overall, volcanic quartz crystals preserve complex, overprinted deformation textures indicating that quartz crystals have prolonged deformation histories throughout storage, fragmentation, and eruption.

58 GEOSCIENCES↗
DOE OSTI2017

Analysis of thermal history effects on mechanical anisotropy of 3D-printed polymer matrix composites via in situ X-ray tomography

The tensile behavior of an additively manufactured (AM) polymer matrix composite (PMC) is studied with in situ X-ray computed microtomography (CT) and digital volume correlation (DVC). In this experiment, the effects of recycled material content and print direction on the selective laser-sintered (SLS) material's mechanical response are explored. The PMC samples are printed in a tensile specimen geometry with gage lengths parallel to all three orthogonal, primary sintering directions. In situ tensile-CT experiments are conducted at Argonne National Laboratory's Advanced Photon Source 2-BM beamline. Analysis of the AM PMC's tensile response, failure, and strain evolution is analyzed both from a conventional standpoint, using the load-displacement data recorded by the loading fixture, and from a microstructural standpoint by applying DVC analysis to the reconstructed volumes. Significant variations on both strength and ductility are observed from both vantages with respect to print direction and the recycled material content in the printed parts. As a result, it is found that the addition of recycled source material with a thermal history reduces the tensile strength of the SLS composite for all directions, but the effect is drastic on the strength in the layering direction.

36 MATERIALS SCIENCE↗
DOE OSTI2023

Insights into the thermal history of carbon fibers using Raman spectroscopy and a novel kinetic model

Carbon fibers and carbon fiber composites are applied in high-performance applications, but a key consideration for application is their relative sensitivity to oxidative environments. To enable in-situ characterization of carbon fibers exposed to oxidative conditions, the Raman spectral response of T700 carbon fibers that have been exposed to a variety of dwell temperatures is reported herein with dwell times reaching up to 1 month. Here, we evaluate the spectra holistically by using integrated absolute difference analysis. By combining this analysis with straightforward kinetic models, we connect the total Raman spectral response to the temperature-time curve that could yield such a shift in spectral parameters. Our work connects the Raman spectral response of carbon fibers to their thermal history and can easily be extended to other graphitic materials, such as nuclear graphite.

36 MATERIALS SCIENCE↗
DOE OSTI2023

Noble gas constraints on spent fuel irradiation histories

Fission gas isotopic compositions are sensitive to a variety of reactor operating parameters that include the neutron flux, neutron fluence at different neutron energies, and operating temperature. Measurements of fission gas isotopic compositions thus have potential to constrain reactor simulations for nuclear forensics and safeguards applications. In this paper, we present Kr and Xe isotope measurements from a suite of samples obtained from locations that span the axial length a fuel pin with a well-characterized irradiation history and compare these data to spatially resolved reactor simulations. Here, we observed positive correlations between fluence sensitive isotopic ratios and burnup and between a flux sensitive ratio and power, although some discrepancies are observed between the measured data and model predictions. These differences may be due to simplifications in the model and/or inaccuracies in the cross sections. A much broader measurement to model comparison is required to better understand the discrepancies.

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS↗
DOE OSTI2017

Characterization of Flame Cut Heavy Steel: Modeling of Temperature History and Residual Stress Formation

Heavy steel plates are used in demanding applications that require both high strength and hardness. An important step in the production of such components is cutting the plates with a cost-effective thermal cutting method such as flame cutting. Flame cutting is performed with a controlled flame and oxygen jet, which burns the steel and forms a cutting edge. However, the thermal cutting of heavy steel plates causes several problems. A heat-affected zone (HAZ) is generated at the cut edge due to the steep temperature gradient. Consequently, volume changes, hardness variations, and microstructural changes occur in the HAZ. In addition, residual stresses are formed at the cut edge during the process. In the worst case, unsuitable flame cutting practices generate cracks at the cut edge. The flame cutting of thick steel plate was modeled using the commercial finite element software ABAQUS. The results of modeling were verified by X-ray diffraction-based residual stress measurements and microstructural analysis. The model provides several outcomes, such as obtaining more information related to the formation of residual stresses and the temperature history during the flame cutting process. In addition, an extensive series of flame cut samples was designed with the assistance of the model.

36 MATERIALS SCIENCE↗
DOE OSTI2012

The history of neutrinos, 1930-1985. What have we learned about neutrinos? What have we learned using neutrinos?

An attempt to remember some of the main events which highlight the evolution of our knowledge of the neutrinos and their properties, the 'families' of particles, a few of the very interesting persons who contributed to this progress, as well as the contribution of neutrino beam experiments to the validation of the electro-weak and quantum-chromo-dynamic theories, and the structure of the nucleon. - Highlights: Black-Right-Pointing-Pointer Early history: continuity of {beta}-spectrum, Pauli letter, universal Fermi interaction. Black-Right-Pointing-Pointer Neutrino beams and the discovery of the muon neutrino. Black-Right-Pointing-Pointer Gargamelle, the discovery of the neutral current and the verification of the quark-gluon nature of the parton. Black-Right-Pointing-Pointer Deep inelastic scattering at higher energies: scaling, quantitative verification of QCD, structure functions.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗