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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 235 records · Page 13
All sourcesNASA NTRSDOE OSTI
DOE OSTI2025

Finite element analysis of the impact of beam heating mode in molten salt corrosion experiments employing simultaneous ion irradiation

Finite element analysis was used to investigate the temperature and stress profiles that develop in 316L stainless steel membranes being irradiated using different proton beam conditions in contact with a molten salt environment. It was shown that in addition to a nonuniform irradiation profile, a focused 2 MeV proton beam leads to very strong temperature and stress gradients in the membrane, introducing highly localized driving forces that complicate and even compromise the integrity and reliability of the experimental results of corrosion studies. Here, the use of a focused beam in corrosion studies can create experimental artifacts that may misrepresent the true corrosion behavior. In contrast, the use of a rastered beam is shown to distribute the protons and resulting radiation damage uniformly across the membrane face, and more importantly, results in temperature and stress profiles that are not only very uniform but are of much lower magnitude. The use of a rastered beam during molten salt corrosion experiments is therefore recommended to achieve uniform damage rates, thereby reducing both gradients and magnitudes of the temperature and stress distributions.

43 - PARTICLE ACCELERATORS↗
NASA NTRS2004

H2O2 Synthesis Induced by Irradiation of H2O with Energetic H(+) and Ar(+) Ions at Various Temperatures

The detection of H2O2 on Jupiter's icy satellite Europa by the Galileo NIMS instrument presented a strong evidence for the importance of radiation effects on icy surfaces. A few experiments have investigated whether solar flux of protons incident on Europa ice could cause a significant if any H2O2 production. These published results differ as to whether H2O2 can be formed by ions impacting water at temperatures near 80 K, which are appropriate to Europa. This discrepancy may be a result of the use of different incident ion energies, different vacuum conditions, or different ways of processing the data. The latter possibility comes about from the difficulty of identifying the 3.5 m peroxide OH band on the long wavelength wing of the much stronger water 3.1 m band. The problem is aggravated by using straight line baselines to represent the water OH band with a curvature, in the region of the peroxide band, that increases with temperature. To overcome this problem, we use polynomial baselines that provide good fits to the water band and its derivative.

Baragiola, R. A.↗
DOE OSTI2025

Mechanistic Insights into Oxygen Reduction Reaction on Metal Cathode Over BaZrO 3 -Based Electrolyte under Moist Atmosphere: Interfacial Interactions and Reaction Pathways

The oxygen reduction reaction (ORR) is a critical process that often governs the overall performance of electrochemical systems such as proton conducting solid oxide fuel cells. Despite its significance, the current understanding about the ORR, especially when it involves H 2 O is still limited. In this study, the proton involved ORR (PI-ORR) on metal cathode (e.g., Pt) over BaZrO 3 (BZO) electrolyte is investigated using density functional theory (DFT) under moist atmosphere. Two scenarios are considered: one at relatively high temperature (900 K) in the presence of oxygen vacancy in BZO substrate and one at relatively low temperature (700 K) without oxygen vacancy. We systematically explored oxygen vacancy effects on adsorption sites and proton transfer pathways, calculated energy profiles and Gibbs free energies for elementary steps along the O 2 dissociated and the O 2 concerted reaction pathways. We also evaluated H 2 O impacts on intermediate oxygen species (*O and *OH) through Ab Initio molecular dynamics. These analyses revealed pathway-dependent reaction mechanisms and hydration effects at triple-phase boundary, advancing fundamental understanding of PI-ORR in metal cathode/Ba-based electrolyte systems for energy applications.

08 - HYDROGEN↗
NASA NTRS2008

Global Circulation and Impact of Plasmaspheric Plumes

We report results from the global circulation model of Lyon, Fedder, and Mobarry with an embedded model of the inner magnetosphere including the plasmasphere. The combination is used to initiate large numbers of representative protons on the geosynchronous orbit L shell, to assign particle weightings, to track their: subsequent trajectories in the 3D fields. This permits us to study the global circulation of plasmaspheric plumes and to compare these with Polar observations from the dayside magnetopause region . A range of events is studied from an isolated period of SBz in the solar wind,to a large storm sequence. We consider effects on circulating plasma reaching the dayside reconnection X-line, the population of the plasma sheet with ionospheric protons and the generation of ring current pressure from this source, compared with solar wind, polar wind, and auroral wind sources. We find that the transient plasmaspheric plume source is large in terms of total fluence, but of modest proportions in terms of contribution to the ring current. Implications of this and other results for improved space weather modeling and prediction will be discussed.

Moore, Thomas E.↗
NASA NTRS2018

Solar Wind Induced Waves in the Skies of Mars: Ionospheric Compression, Energization, and Escape Resulting from the Impact of Ultralow Frequency Magnetosonic Waves Generated Upstream of the Martian Bow Shock

Using data from the National Aeronautics and Space Administration Mars Atmosphere and Voltatile EvolutioN and the European Space Agency Mars Express spacecraft, we show that transient phenomena in the foreshock and solar wind can directly inject energy into the ionosphere of Mars. We demonstrate that the impact of compressive ultralow frequency waves in the solar wind on the induced magnetospheres drive compressional, linearly polarized, magnetosonic ultralow frequency waves in the ionosphere, and a localized electromagnetic "ringing" at the local proton gyro frequency. The pulsations heat and energize Ionospheric plasmas. A preliminary survey of events shows that no special upstream conditions are required in the interplanetary magnetic field or solar wind. Elevated ion densities and temperatures in the solar wind near to Mars are consistent with the presence of an additional population of Martian ions, leading to ion-ion instabilities, associated wave-particle interactions, and heating of the solar wind. The phenomenon was found to be seasonal, occurring when Mars is near perihelion. Finally, we present simultaneous multipoint observations of the phenomenon, with the Mars Express observing the waves upstream, and Mars Atmosphere and Voltatile EvolutioN observing the response in the ionosphere. When these new observations are combined with decades of previous studies, they collectively provide strong evidence for a previously undemonstrated atmospheric loss process at unmagnetized planets: ionospheric escape driven by the direct impact of transient phenomena from the foreshock and solar wind.

Collinson, Glyn↗
DOE OSTI2024

Impact of the newly revised gravitational redshift of x-ray burster GS 1826-24 on the equation of state of supradense neutron-rich matter

Thanks to the recent advancement in producing rare isotopes and measuring their masses with unprecedented precision, the updated nuclear masses around the waiting-point nucleus 64 Ge in the rapid-proton capture process have led to a significant revision of the surface gravitational redshift of the neutron star (NS) in GS 1826-24 by refitting its x-ray burst light curve using Modules for Experiments in Stellar Astrophysics (MESA). The resulting NS compactness ξ is between 0.183 and 0.259 at 95% confidence level, and its upper boundary is significantly smaller than the maximum ξ previously known. Incorporating these new data within a comprehensive Bayesian statistical framework, we investigate its impact on the Equation of State (EOS) of supradense neutron-rich matter and the required spin frequency for GW190814’s minor m 2 with mass 2.59 ± 0.05⁢M ⊙ to be a rotationally stable pulsar. We found that the EOS of high-density symmetric nuclear matter (SNM) has to be softened significantly while the symmetry energy at supersaturation densities stiffened compared to our prior knowledge from earlier analyses using data from both astrophysical observations and terrestrial nuclear experiments. In particular, the skewness J 0 characterizing the stiffness of high-density symmetric nuclear matter (SNM) decreases significantly, while the slope L, curvature K sym , and skewness Jsym of nuclear symmetry energy all increase appreciably compared to their fiducial values. Here, we also found that the most probable spin rate for the m 2 to be a stable pulsar is very close to its mass-shedding limit once the revised redshift data from GS 1826-24 is considered, making the m 2 unlikely the most massive NS observed so far.

79 ASTRONOMY AND ASTROPHYSICS↗
DOE OSTI2024

Proton-Coupled Electron Transfer Mechanisms for CO 2 Reduction to Methanol Catalyzed by Surface-Immobilized Cobalt Phthalocyanine

Immobilized cobalt phthalocyanine (CoPc) is a highly promising architecture for the six-proton, six-electron reduction of CO 2 to methanol. This electroreduction process relies on proton-coupled electron transfer (PCET) reactions that can occur by sequential or concerted mechanisms. Immobilization on a conductive support such as carbon nanotubes or graphitic flakes can fundamentally alter the PCET mechanisms. We use density functional theory (DFT) calculations of CoPc adsorbed on an explicit graphitic surface model to investigate intermediates in the electroreduction of CO 2 to methanol. Our calculations show that the alignment of the CoPc and graphitic electronic states influences the reductive chemistry. These calculations also distinguish between charging the graphitic surface and reducing the CoPc and adsorbed intermediates as electrons are added to the system. This analysis allows us to identify the chemical transformations that are likely to be concerted PCET, defined for these systems as the mechanism in which protonation of a CO 2 reduction intermediate is accompanied by electron abstraction from the graphitic surface to the adsorbate without thermodynamically stable intermediates. Furthermore, this work establishes a mechanistic pathway for methanol production that is consistent with experimental observations and provides fundamental insight into how immobilization of the CoPc impacts its CO 2 reduction chemistry.

Adsorption↗
NASA NTRS2016

Electromagnetic Dissociation Cross Sections for High LET Fragments

Nuclear interaction cross sections are used in space radiation transport codes to calculate the probability of fragment emission in high energy nucleus-nucleus collisions. Strong interactions usually dominate in these collisions, but electromagnetic (EM) interactions can also sometimes be important. Strong interactions typically occur when the projectile nucleus hits a target nucleus, with a small impact parameter. For impact parameters larger than the sum of the nuclear radii, EM reactions dominate and the process is called electromagnetic dissociation (EMD) if one of the nuclei undergo fragmentation. Previous models of EMD have been used to calculate single proton (p) production, single neutron (n) production or light ion production, where a light ion is defined as an isotope of hydrogen (H) or helium (He), such as a deuteron (2H), a triton (3H), a helion (3He) or an alpha particle (4He). A new model is described which can also account for multiple nucleon production, such as 2p, 2n, 1p1n, 2p1n, 2p2n, etc. in addition to light ion production. Such processes are important to include for the following reasons. Consider, for example, the EMD reaction 56Fe + Al --> 52Cr + X + Al, for a 56Fe projectile impacting Al, which produces the high linear energy transfer (LET) fragment 52Cr. In this reaction, the most probable particles representing X are either 2p2n or 4He. Therefore, production of the high LET fragment 52Cr, must include the multiple nucleon production of 2p2n in addition to the light ion production of 4He. Previous models, such as the NUCFRG3 model, could only account for the 4He production process in this reaction and could not account for 2p2n. The new EMD model presented in this work accounts for both the light ion and multiple nucleon processes, and is therefore able to correctly account for the production of high LET products such as 52Cr. The model will be described and calculations will be presented that show the importance of light ion and multiple nucleon production. The work will also show that EMD reactions contribute most to those fragments with the highest LET.

Norbury, John↗
DOE OSTI2026

Concerted Proton–Electron Transfer Minimizes Substituent Effects on Adsorbed Phthalocyanine Electrocatalysis

Molecularly modified electrodes (MMEs) are potent electrocatalysts, but few principles exist for their rational design. Electrocatalysis by soluble molecules depends strongly on substituents that tune the catalyst redox potential (E 1/2 ), but it is unclear if this parameter similarly impacts MME catalysis. Herein, we employ the hydrogen evolution reaction (HER) as a test case for comparing carbon-adsorbed cobalt phthalocyanine (CoPc/C) and cobalt hexadecafluoro-phthalocyanine (CoFPc/C). By correlating HER activity and voltammetric data to total Co surface concentration across a wide range of catalyst loadings, we find that only 5–25% of adsorbed Co sites contribute to the Co(II/I) redox wave and that this subpopulation poorly correlates with catalytic activity. Instead, in the low-loading limit, catalytic activity correlates linearly with the majority Co(II/I)-silent Co population, revealing per-site turnover frequency (TOF) values for HER. Despite a 230 mV difference in Co(II/I) redox potentials, CoPc/C and CoFPc/C display TOF values differing by less than a factor of 3 when compared over a wide potential range. Mechanistic studies point to an inner-sphere concerted proton–electron transfer step as rate-determining, suggesting that the Co–H bond dissociation free energy (BDFE) rather than the Co(II/I) E 1/2 is thermodynamically relevant. Computational studies indicate that the fluoro-substituents lead to compensatory changes in Co(II/I) E 1/2 and Co(I) basicity, leaving the Co–H BDFE largely unchanged between CoPc and CoFPc and thereby manifesting in similar catalytic rates. Furthermore, these results highlight the limited effect of E 1/2 -tuning on MME catalytic activity and motivate the development of methods to directly alter active site–substrate BDFE.

Catalysts↗
NASA NTRS2024

Multispacecraft Observations of a Widespread Solar Energetic Particle Event on 2022 February 15–16

On 2022 February 15–16, multiple spacecraft measured one of the most intense solar energetic particle (SEP) events observed so far in Solar Cycle 25. This study provides an overview of interesting observations made by multiple spacecraft during this event. Parker Solar Probe (PSP) and BepiColombo were close to each other at 0.34–0.37 au (a radial separation of ∼0.03 au) as they were impacted by the flank of the associated coronal mass ejection (CME). At about 100° in the retrograde direction and 1.5 au away from the Sun, the radiation detector on board the Curiosity surface rover observed the largest ground-level enhancement on Mars since surface measurements began. At intermediate distances (0.7–1.0 au), the presence of stream interaction regions (SIRs) during the SEP arrival time provides additional complexities regarding the analysis of the distinct contributions of CME-driven versus SIR-driven events in observations by spacecraft such as Solar Orbiter and STEREO-A, and by near-Earth spacecraft like ACE, SOHO, and WIND. The proximity of PSP and BepiColombo also enables us to directly compare their measurements and perform cross-calibration for the energetic particle instruments on board the two spacecraft. Our analysis indicates that energetic proton measurements from BepiColombo and PSP are in reasonable agreement with each other to within a factor of ∼1.35. Finally, this study introduces the various ongoing efforts that will collectively improve our understanding of this impactful, widespread SEP event.

Solar energetic particles↗
DOE OSTI2025

Baryon number violation: from nuclear matrix elements to BSM physics

Processes that violate baryon number, most notably proton decay and $n\bar{n}$ transitions, are promising probes of physics beyond the Standard Model (BSM) needed to understand the lack of antimatter in the Universe. To interpret current and forthcoming experimental limits, theory input from nuclear matrix elements to UV complete models enters. Thus, an interplay of experiment, effective field theory, lattice QCD, and BSM model building is required to develop strategies to accurately extract information from current and future data and maximize the impact and sensitivity of next-generation experiments. Here, we briefly summarize the main results and discussions from the workshop ‘INT-25-91W: Baryon Number Violation: From Nuclear Matrix Elements to BSM Physics,’ held at the Institute for Nuclear Theory, University of Washington, Seattle, WA, 13–17 January 2025.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗
DOE OSTI2025

Measurement of correlations among net-charge, net-proton, and net-kaon multiplicity distributions in Pb-Pb collisions at $\sqrt{s_{NN}}$ = 5.02 TeV

Correlations among conserved quantum numbers, such as the net-electric charge, the net-baryon, and the net-strangeness in heavy-ion collisions, are crucial for exploring the QCD phase diagram. In this paper, these correlations are investigated using net-proton number (as a proxy for the net-baryon), net-kaon number (for the net-strangeness), and net-charged particle number in Pb-Pb collisions at $\sqrt{s_{NN}}$ = 5.02 TeV with the ALICE detector. The observed correlations deviate from the Poissonian baseline, with a more pronounced deviation at LHC energies than at RHIC. Theoretical calculations of the Thermal-FIST hadron resonance gas model, HIJING, and EPOS LHC event generators are compared with experimental results, where a significant impact of resonance decays is observed. Thermal-FIST calculations under the grand canonical and canonical ensembles highlight significant differences, underscoring the role of local charge conservation in explaining the data. Recent lattice QCD studies have demonstrated that the magnetic field generated by spectator protons in heavy-ion collisions affects susceptibility ratios, in particular those related to the net-electric charge and the net-baryon numbers. The experimental findings are in qualitative agreement with the expectations of lattice QCD.

73 NUCLEAR PHYSICS AND RADIATION PHYSICS↗
DOE OSTI2026

The Synthesis and Ring-Opening Metathesis Polymerization of Energetic Norbornene Materials

Energetic norbornenes are promising candidates toward the development of new energetic polymers due to the synthetic versatility of norbornene ring-opening metathesis polymerizations used in commercial applications. We report the synthesis of two energetic norbornene materials that can be made in two steps with modest yields, containing either trinitroethanol or fluorodinitroethanol substituents. The norbornene monomers were then polymerized, and the polymers were characterized by Fourier transform infrared spectroscopy (FT-IR), differential scanning calorimetry (DSC), contact angle measurements, and proton and carbon nuclear magnetic resonance spectroscopies ( 1 H and 13 C{ 1 H} NMR). Additionally, small-scale safety data consisting of electrostatic discharge (ESD), friction (FS), and impact (IS) sensitivities were measured for the norbornene monomers and their resulting polymers. These analyses revealed that energetic norbornene materials are relatively insensitive and have densities comparable to that of TNT (1.47–1.81 g·cm –3 ).

36 MATERIALS SCIENCE↗
NASA NTRS2005

Lunar and Planetary Science XXXVI, Part 20

The topics include: 1) Virtual Reality Technology as a Tool to Enhance Collaboration Between Space Exploration and Public Outreach: The Case Using the Mars Exploration Rover Images; 2) Atmospheric Electron-induced X-Ray Spectrometer (AEXS) Instrument Development; 3) Impact of Low Thermal Conductivity Layers on the Bulk Conductivity of a Martian Crustal Column; 4) Impacting Classroom Teachers Through Long-Term Professional Development; 5) Oxygen, Ca, and Ti Isotopic Compositions of Hibonite-bearing Inclusions; 6) Phenomenological Excitation Functions of Xe Isotopes with Protons on Nuclei of Cs, La and Ce; 7) Double-Diffusive Convection and Other Modes of Salinity-modulated Heat and Material Transport in Europa s Ocean; 8) Slope Morphologies of the Hellas Mensae Constructs, Eastern Hellas Planitia, Mars; 9) Development of Polygonal Thermal Contraction Patterns in a South Polar Trough, Mars 3 Years of Observations; 10) Martian Relevance of Dehydration and Rehydration in the Mg-Sulfate System; 11) Formation of Martian Volcanic Provinces by Lower Mantle Flushing? 12) Can Glasses Help Us to Unravel the Origin of Barred Olivine Chondrules? 13) Loki Patera: A Magma Sea Story; 14) Compositions of Partly Altered Olivine and Replacement Serpentine in the CM2 Chondrite QUE93005; 15) Model of Light Scattering by Lunar Regolith at Moderate Phase Angles: New Results; 16) Radiation Resistance of a Silicone Polymer Grease Based Regolith Collector for the HERA Near-Earth Asteroid Sample Return Mission; 17) Analysis of the Tectonic Lineaments in the Ganiki Planitia (V14) Quadrangle, Venus; 18) Nanometer-sized Diamonds from AGB Stars; 19) Quantifying Exact Motions Along Lineaments on Europa; 20) Geometry of Thrust Faults Beneath Amenthes Rupes, Mars; 21) Mapping of the Physical Characteristics and Mineral Composition of a Superficial Layer of the Moon or Mars and Ultra-Violet Polarimetry from the Orbital Station; 22) Negative Searches for Evidence of Aqueous Alteration on Asteroid Surfaces; 23) What Processes Have Shaped Basalt Boulders on Earth and Mars? Studies of Feature Persistence Using Facet Mapping and Fractal Analysis; 24) The Popigai Fluidizites: Dense Water Inclusions in Lechatelierite; Evidence for Shock-generated Carbonate and Hydrous Silicate Melts; 25) Missing Xenon Problem and Climate of the Early Earth; and 26) More on Magnetic Spectra from Correlated Crustal Sources on Mars

Source record↗
NASA NTRS2016

Prompt Injections of Highly Relativistic Electrons Induced by Interplanetary Shocks: A Statistical Study of Van Allen Probes Observations

We conduct a statistical study on the sudden response of outer radiation belt electrons due to interplanetary (IP) shocks during the Van Allen Probes era, i.e., 2012 to 2015. Data from the Relativistic Electron-Proton Telescope instrument on board Van Allen Probes are used to investigate the highly relativistic electron response (E greater than 1.8 MeV) within the first few minutes after shock impact. We investigate the relationship of IP shock parameters, such as Mach number, with the highly relativistic electron response, including spectral properties and radial location of the shock-induced injection. We find that the driving solar wind structure of the shock does not affect occurrence for enhancement events, 25% of IP shocks are associated with prompt energization, and 14% are associated with MeV electron depletion. Parameters that represent IP shock strength are found to correlate best with highest levels of energization, suggesting that shock strength may play a key role in the severity of the enhancements. However, not every shock results in an enhancement, indicating that magnetospheric preconditioning may be required.

Schiller, Q.↗
DOE OSTI2025

Epoxide Alcoholysis over M-BEA Zeolites: Effects of Alcohol Chain Length on Rates and Regioselectivities

The structures of nucleophilic reactants affect their coordination behavior among solvent molecules and kinetics of reactions with surface intermediates within the confines of fluidfilled pores of zeolites and other microporous materials. Consequently, rates and regioselectivities of diverse chemistries may depend sensitively on nucleophile identity in manners not observed for classic fluid phase reactions. Here, we examine the impact of varying the primary alcohol (ROH) chain length on the kinetics of 1,2-epoxybutane (C 4 H 8 O) ring-opening within Brønsted (Al-BEA) and Lewis acid (Zr-BEA) zeolites. Turnover rates increase by factors of ∼6 (Al-BEA) and 4-fold (Zr-BEA) between methanol and 1-hexanol, yet the reaction mechanisms remain comparable. Despite modest rate differences, apparent activation enthalpies calculated from rates and activities of solvated reactants decrease linearly by 12 (Al-BEA) to 33 kJ mol −1 (Zr- BEA) with increased proton affinity, which suggests bond formation energies for the nucleophile strongly influence rate increases. The molecular interpretation of these trends demonstrates, however, that the solvation of ring-opening transition states by zeolite pore structures and solvent molecules also governs rates. The impact of local solvating interactions appears most directly as changes in regioselectivities, which tend to enhance terminal alcohol formation with increasing ROH chain length. Regioselectivities largely do not vary with differences in fluid composition for a given ROH. The addition of H 2 O increases the number of hydrogen bonds among reactive species, and trends in regioselectivities imply that the decreased hydrogen bonding ability of longer chain ROH, and not the nucleophile strength or steric bulk, determines the regioselectivities of the resulting products. This work provides direct experimental evidence that nucleophilicity and hydrogen bonding influence reaction barriers and regioselectivities in zeolitecatalyzed epoxide ring-opening, offering pathways to better control reaction kinetics.

acidic zeolites↗
NASA NTRS1985

Low P sub T hadron-nucleus interactions

The possibility of describing hadron-nucleus (hA) interactions is discussed in terms of a number of independent collisions of the projectile inside the target nucleus. This multiple rescattering may occur on a particle or quark parton level. To investigate the characteristics of hA interactions as a function of antineutrinos advantage is taken of the correlation between the average number antineutrinos of collisions of the projectile inside the nucleus and the number Ng of fast protons ejected from the struck nucleus. The relation antineutrinos vs Ng obtained in antineutrinos was used. For a given target nucleus this allows the selection of interactions occurring at different impact parameters.

Holynski, R.↗
NASA NTRS2004

Lunar and Planetary Science XXXV: Dust: Theory and Experiments

The titles in this section include: 1) Experimental Study of the Radiation Pressure Forces on Isolated Micron-size Dust Particles; 2) Migration of Dust Particles and Their Collisions with the Terrestrial Planets; 3) Chemical In-Situ Analysis of Interplanetary and Interstellar Meteoroids; 4) Mass Spectrometer Calibration of Cassini Cosmic Dust Analyzer for Methane Ice via Laser Ablation; 5) Comparative Effects of 10.2 eV Photon and 200 keV Proton Irradiation on Condensed CO; 6) Experimental Studies on Heated and Unheated He-Irradiated Olivine Grains at Moderate He-Ion Fluences: Analogues to Radiation Damage in IDPs; 7) Impact Studies Using a One Stage Light Gas Gun; 8) Condensation Kinetics of Metallic Iron: An Experimental Study.

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