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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 19 records

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NASA NTRS1988

Superconductivity in the high-Tc Bi-Ca-Sr-Cu-O system - Phase identification

Four phases are observed in superconducting Bi-Ca-Sr-Cu-O samples. The superconducting phase, with onset temperature near 120 K, is a 15.4-A-layered compound with composition near Bi2Ca1Sr2Cu2O9 and an A-centered orthorhombic unit subcell 5.41 x 5.44 x 30.78 A. X-ray diffraction and electron microscopy data are consistent with a structure of alternating perovskite and Bi2O2 layers. High-resolution transmission electron microscopy images reveal a b-axis superstructure of 27.2 A, numerous (001) stacking faults, and other defects.

Hazen, R. M.↗

NASA NTRS2023

Mineralogical, Elemental, and Tomographic Reconnaissance Investigation for CLPS (METRIC)

METRIC is a robotic science laboratory that can determine the mineralogy, elemental chemistry, micromorphology, and thermophysical properties of planetary regolith. The METRIC suite comprises METRIC XRD/F, an X-ray diffraction/X-ray fluorescence instrument that can determine the mineralogy and elemental chemistry of regolith samples; METRIC XCT, a micro X-ray computed tomography instrument that can be used to evaluate grain/crystallite sizes and textures; METRIC IRS, an imaging spectrometer mounted on a rover that can determine mineralogy and thermophysical properties at the landing site; and a pneumatic sample collection, processing, distribution system developed by Honeybee Robotics. The payload elements could be deployed on a static lander or a rover. Data returned from the METRIC payload would inform origin, formation, and evolution of rocky planetary bodies. METRIC XRD/F draws on heritage from the CheMin instrument on the Mars Science Laboratory (MSL) Curiosity rover [1], with a few important improvements. Like CheMin, METRIC XRD/F operates in transmission geometry and uses piezoelectric actuators on sample cells in a tuning fork geometry to induce convective grain motion of the regolith to create a randomly oriented powder. MSL CheMin uses an energy-sensitive CCD to collect XRD patterns and XRF spectra simultaneously from the same sample cell, resulting in qualitative XRF data. METRIC XRD/F uses two different sample cells, one optimized for XRD and one optimized for XRF, and a silicon drift detector to detect fluoresced X-rays. This improvement to the XRF capabilities provides quantitative geochemical data of major elements down to Z = 11 and allows for the detection of minor and trace elements that are critical for evaluating geologic evolution of the Moon (e.g., P and Th). Modest improvements to the XRD geometry and hardware allow for better angular resolution and the ability to distinguish between members of the pyroxene group. METRIC XCT uses the same geometry and much of the same hardware as METRIC XRD/F, where a CCD would capture images of a regolith sample in a 3 mm diameter sample tube that is rotated 360° in steps <1°. Image brightness can be used to infer compositional data, where brighter materials indicate a higher Z, much like scanning electron microscopy. Data from METRIC XCT complement those from METRIC XRD/F. Particle size, shape, and texture can provide petrologic and provenance information, whereas vesicle size and morphology in volcanic or impact melt lithologies can inform cooling rates. METRIC IRS is a hyperspectral thermal imager that can be mounted to a lander or rover to provide mineralogical data from the broader landing site and help determine whether the samples analyzed by METRIC XRD/F and XCT are representative. The METRIC IRS spectral range (8–14 μm) and resolution (10.8 cm-1) allow for quantitative mineralogy from modelling Reststrahlen bands of major rock-forming minerals (e.g., silicates, phosphates). Radiance cubes can be processed and modelled with an onboard high-performance computer to determine mineral abundances of plagioclase, high-Ca pyroxene, pigeonite, orthopyroxene, olivine, and glass. Regolith samples can be acquired, processed, and delivered to the X-ray instruments via multiple sample handling systems, but the pneumatic sampling systems developed by Honeybee Robotics [e.g., 2] are best suited for relatively low-cost missions that are being competed for the Moon (e.g., NASA’s Payloads and Research Investigations for the Surface of the Moon program). There are pneumatic sampling systems that collect surface material and other systems that pneumatically drill up to ~1 m below the surface, providing material that has not been space weathered and has not been affected by the lander’s exhaust. [1] Blake, D. F., Vaniman, D., Achilles, C., Anderson, R., Bish, D., et al. (2012). Space Sci. Rev. 170, 341-478. https://doi.org/10.1007/s11214-012-9905-1. [2] Zacny, K., Betts, B., Hedlund, M., Long, P., Gramlich, M., Tura, K., Chu, P., Jacob, A., Garcia, A. (2014). IEEE Aerospace Conference, 3-7 March 2014, Big Sky, MT, U.S.A.

X-ray diffraction↗

NASA NTRS2022

Multiscale Progressive Failure Analysis of 3D Woven Composites

Application of three-dimensional (3D) woven composites is growing as an alternative to the use of ply-based composite materials. However, the design, analysis, modeling, and optimization of these materials is more challenging due to their complex and inherently multiscale geometries. Herein, a multiscale modeling procedure, based on efficient, semi-analytical micromechanical theories rather than the traditional finite element approach, is presented and applied to a 3D woven carbon–epoxy composite. A crack-band progressive damage model was employed for the matrix constituent to capture the globally observed nonlinear response. Realistic microstructural dimensions and tow-fiber volume fractions were determined from detailed X-ray computed tomography (CT) and scanning electron microscopy data. Pre-existing binder-tow disbonds and weft-tow waviness, observed in X-ray CT scans of the composite, were also included in the model. The results were compared with experimental data for the in-plane tensile and shear behavior of the composite. The tensile predictions exhibited good correlations with the test data. While the model was able to capture the less brittle nature of the in-plane shear response, quantitative measures were underpredicted to some degree.

3D woven composites↗

NASA NTRS1984

Homogeneous condensation of gaseous mixtures of Si, Fe, O, N, and C in relative cosmic abundance and implications for astronomical condensation

The pressure versus temperature curves for homogeneous nucleation and condensation of two gaseous mixtures with nearly relative solar abundance of Si, Fe, O, N, and C in an excess of H were determined experimentally. Mixtures of CO, Fe(CO)5, H2, SiH4, and N2O in Ar were heated behind reflected shocks in a shock tube. The nucleation and condensation, which took place in the subsequent gas-dynamic expansion (cooling phase), was monitored by light scattering and turbidity. Grain morphologies and crystalline phases present in the condensates were determined by electron microscopy. These data cast doubt on the validity of both equilibrium and classical nucleation theoretical approaches to predict homogeneous condensation in a solar nebula or stellar atmosphere.

Stephens, J. R.↗

NASA NTRS1993

Transformation to Ni5Al3 in a 63.0 at. pct Ni-Al alloy

Microstructures of 63 at. pct P/M Ni-Al alloys with a composition close to the stoichiometry of the Ni5Al3 phase were investigated using homogenized and quenched specimens aged at low temperatures for various times. Results of analyses of XRD data and electron microscopy observations were used for quantitative phase analysis, performed to calculate the (NiAl + Ni5Al3)/Ni5Al3 phase boundary locations. The measured lattice parameters of Ni5Al3 phase formed at 823, 873, and 923 K indicated an increase in tetragonality of the phase with increasing nickel content.

Khadkikar, P. S.↗

NASA NTRS1992

Purification and immunolocalization of an annexin-like protein in pea seedlings

As part of a study to identify potential targets of calcium action in plant cells, a 35-kDa, annexin-like protein was purified from pea (Pisum sativum L.) plumules by a method used to purify animal annexins. This protein, called p35, binds to a phosphatidylserine affinity column in a calcium-dependent manner and binds 45Ca2+ in a dot-blot assay. Preliminary sequence data confirm a relationship for p35 with the annexin family of proteins. Polyclonal antibodies have been raised which recognize p35 in Western and dot blots. Immunofluorescence and immunogold techniques were used to study the distribution and subcellular localization of p35 in pea plumules and roots. The highest levels of immunostain were found in young developing vascular cells producing wall thickenings and in peripheral root-cap cells releasing slime. This localization in cells which are actively involved in secretion is of interest because one function suggested for the animal annexins is involvement in the mediation of exocytosis.

NASA Discipline Number 40-50↗

NASA NTRS2014

A Predictive Bubble Point Pressure Model for Porous Liquid Acquisition Device Screens

This article presents a simplified model for porous screen channel liquid acquisition devices based on a maximum bubble point pressure method from Adamson and Gast (1997). To validate the model, three 304 stainless steel (325 × 2300, 450 × 2750, and 510 × 3600) mesh samples were tested in methanol, acetone, isopropyl alcohol, and water. Screen pores are estimated based on analysis from scanning electron microscopy, historical data, and current test data. Results show that the bubble point pressure is proportional to the surface tension of the fluid only when accounting for nonzero contact angles. The previous assumption that bubble point pressure scales inversely with effective pore diameter is shown to be invalid, as the second finest 450 × 2750 produced the highest bubble point of the three screens. The simplified bubble point model can be used to make predictions for any pure fluid when pore diameters are based on bubble point tests and not SEM analysis.

Liquid Acquisition Device↗

NASA NTRSDate not supplied

Apollo Sample 64455: Petrologic and Geochemical Characterization of a Glass-Coated Impact Melt Rock

Introduction and Background: Impact melts are a key product of the impact cratering process. Impact melts can turbulently entrain pre-existing rock fragments, and melt part of those entrained materials until thermal equilibrium is achieved [1–3]. Lunar impact melt rocks are valuable for determining the precise ages of basin-forming and cratering events, which anchor the cratering chronology and dynamics of the entire solar system [4, and references therein]. Additionally, entrained clasts can inform on the petrology and age of crustal materials that predate the melt-forming impact. In lithologies where no pristine samples are available, entrained materials may hold the record of endogenous lunar volatiles, provided we can untangle their impact histories as high temperature impact melt can heat the clasts and may alter their native volatiles or isotopic signatures [5–6]. Here, we characterize an Apollo 16 sample, 64455,70B, in an effort to understand the physical, microstructural, and geochemical consequences of impact melt contact metamorphism. We acquired optical light and x-ray maps of the sample, as well as quantitative analyses via electron probe microanalysis (EPMA). These tasks allow us to better understand the interaction between impact melts and entrained clasts, ultimately closing knowledge gaps in high-temperature impact processing on planetary surfaces. Sample Description: Sample 64455 is an oblong crystalline rock encased in glass to form an egg-like shape [7–8]. The impact melt coating has altered the outer (1 to 2 mm) rind of the crystalline rock and has preserved schlieren. The interior crystalline rock is likely a crystalline impact melt rock based on its bulk Ir content of 2.25 parts per billion [9]. The composition of the impact melt glass rind cannot be solely derived from the crystalline interior, the glassy rind is more aluminous and less magnesian [10]. Neither the crystalline interior nor the glassy rind were radiometrically age dated, although several studies investigated its cosmogenic isotopes and exposure ages, which reveal the sample was exposed on the lunar surface for ~1–2 Ma [11–13]. Preliminary Results: The interior crystalline rock consists primarily of plagioclase with interstitial pyroxene and olivine. Plagioclase grains are zoned and compositions range from An97–89, while pyroxene compositions generally range from En68Fs19Wo13 to En82Fs15Wo3 and olivine are Fo77 to Fo85. Minor phases include Fe-Ni metal, Ca-phosphates, a K- and Si-rich phase, sulfides, and Fe-phosphides. The glass rind contains approximately 44 wt.% SiO2, 25 wt.% Al2O3, 6 wt.% FeO, 8 wt.% MgO, and 14 wt.% CaO, with other oxides at <1 wt.% each, although the composition of the glass becomes more variable closest to the crystalline rock. The rind consists of rounded plagioclase, pyroxene, and olivine crystals with interstitial melt. In some locations, the rounded crystals are surrounded by closely-packed, blade-like crystals, <5 µm in width. These results indicate that the crystalline interior has partially melted where in contact with the high-temperature impact melt and while further investigation is needed, pyroxene may have preferentially melted relative to olivine and plagioclase. Future Work: We plan to conduct electron backscatter diffraction (EBSD) mapping in order to determine crystallinity and crystal orientation. Next using transmission electron microscopy (TEM) data in conjunction with EBSD and EPMA information, we will model the diffusion of moderately volatile elements between the melt and remnant crystals.

A C Stadermann↗

NASA NTRS2019

Further Characterization of Aerosols Sampled on the International Space Station

Spacecraft cabin air quality is of fundamental importance to crew health, with concerns encompassing both gaseous contaminants and airborne particles. Quantification of spacecraft indoor aerosols will increase our understanding of crew exposure and cabin cleanliness. Aerosols on the International Space Station (ISS) have been sampled and brought back to Earth for analysis to characterize the airborne particulate matter in the cabin. Microscopic analyses have been performed to determine morphology and particle size information, and Energy Dispersive X-ray Spectroscopy (EDS) provides information on the chemical elements present in the particles. With the use of IntelliSEM software for computer-controlled scanning electron microscopy (CCSEM), this data provides particle size distribution information and statistics on particle materials. Many of the particles collected were made up of multiple elements and had uncommon morphologies compared to typical indoor aerosols on Earth. These characteristics are thought to be from unique formation mechanisms in the microgravity environment. Several notable particle types are examined further in this work. Bromine-containing particles and cadmium-containing particles are discussed as they constitute a health hazard to crew members. Humans in indoor living and working spaces are typically the single largest particle emission source, and this was observed in the sampled aerosols in ISS as well.

Sampling↗

NASA NTRS1992

X-ray scattering measurements from thin foil X-ray mirrors

Thin foil X-ray mirrors are to be used as the reflecting elements in the telescopes of the X-ray satellites Spectrum-X-Gamma (SRG) and ASTRO-D. High resolution X-ray scattering measurements from the Au coated and dip-lacquered Al foils are presented. These were obtained from SRG mirrors positioned in a test quadrant of the telescope structure and from ASTRO-D foils held in a simple fixture. The X-ray data is compared with laser data and other surface structure data such as STM, atomic force microscopy (AFM), TEM, and electron micrography. The data obtained at Cu K-alpha(1), (8.05 keV) from all the mirrors produced on Al foils shows a scatter which limits the obtainable half-power width to above 1.5 arcmin. Mirrors based on electroformed Ni foils, however, show local regions with a factor of 4 better performance, and they are being developed for future applications.

Christensen, F. E.↗

NASA NTRS1984

Proposed structures for poorly characterized phases in C2M carbonaceous chondrite meteorites

A recent investigation of C2M carbonaceous chondrite meteorite matrices using electron microscopy and High-Resolution Transmission Electron Microscopy (HRTEM) has provided data on the structure and chemistry of Poorly Characterized Phases (PCP). It is suggested that a dominant matrix variety (10 A PCP) has a structure equivalent to iron-rich tochinilite (6Fe0.9S5/Fe, Mg//OHO2/), which consists of coherently intrastratified mackinawite and brucite sheets. In addition, it is proposed that 17 A PCP is a commensurate intergrowth of serpentine and tochinilite layers. Various forms of PCP observed in carbonaceous chondrites appear to be intergrowths of tochinilite, serpentine, and tochinilite-serpentine minerals.

Mackinnon, I. D. R.↗

NASA NTRS1994

Moessbauer mineralogy of calcined Murchison meteorite

The three Antarctic meteorites B7904, Y82162, and Y86720 are unusual because they have characteristics in common with both CI and CM groups and because they apparently underwent thermal alteration after hydrous alteration on their parent body. They are also spectrally similar (visible and near-IR) to C, G, B, and F asteroids, which may imply that the surface materials on those asteroids may have undergone thermal alteration. Based on the reflectance spectra of samples of Murchison (CM2 carbonaceous chondrite) that were thermally altered in the laboratory (cryopumped and initial 10(exp -5) atm H2), Hiroi et al. concluded that putative thermal alteration occurred at temperatures of 600 to 1000 C. Similar experiments have been done on Murchison and reported mineralogical changes based on data from transmission electron diffraction microscopy, electron diffraction, and analytical electron microscopy. We report here the Mossbauer mineralogy of the same samples of thermally-altered Murchison. Mossbauer mineralogy gives the molar distribution of Fe among its oxidation states and iron-bearing mineralogies.

Morris, Richard V.↗

NASA NTRS2003

Fast Characterization of Magnetic Impurities in Single-Wall Carbon Nanotubes

We have demonstrated that the magnetic susceptibility measurement is a non-destructive, fast and accurate method to determine the residual metal catalysts in a few microgram single-wall carbon nanotube (SWCNT) sample. We have studied magnetic impurities in raw and purified SWCNT by magnetic susceptibility measurements, transmission electron microscopy, and thermogravimetry. The data suggest that the saturation magnetic moment and the effective field, which is caused by the interparticle interactions, decreases and increases respectively with the decrease of the particle size. Methods are suggested to overcome the uncertainty associated.

Chen, Feng↗

NASA NTRSDate not supplied

Microstructural Constraints on the Formation of Diamond in Ureilites, the Case from the Kenna Meteorite

The origin of diamonds in ureilitic meteorites, a major family of ultramafic achondrites, has long been debated, with various formation mechanisms inferred, including: 1) shock conversion of preexisting graphite due to a hypervelocity impact on the ureilite parent body; 2) vapor deposition during condensation of the solar nebula; or 3) static transformation in the mantle of a large planetesimal (>1000 km in diameter). The Kenna ureilite is a 10.9 kg stone that was found in Kansas in 1972 and is dominantly composed of olivine and pigeonite (68% and 22% modal abundance, respectively), together with minor metal and carbon-rich regions. Within the carbon-rich domains researchers have identified microdiamonds up to ~10 µm in size. Due to the proximity of the extremely hard microdiamonds with soft graphite and moderately hard silicates, achieving an appropriately flat surface for electron backscatter diffraction (EBSD) analysis has proved challenging. We have, therefore, employed a Hitachi ArBlade 5000 broad beam Ar ion milling system to prepare a sample with an adequate surface uniformity. The ion milling dramatically improved indexing of the EBSD patterns and facilitated high-resolution microstructural analysis of the carbon-rich domains. The carbon-bearing regions occur as tabular domains between polygonal olivine and pigeonite, and are composed of aggregates of micrometer-scale diamond with intermediate graphite, oxides and metal grains. Within the microdiamonds, {111} twins are abundant, many of which form ragged lamellae consistent with mechanical twinning. The microdiamond assemblages appear to pseudomorph tabular graphite habits, which together with the abundant deformation twins, supports a shock transformation mechanism for microdiamond formation within the Kenna meteorite. To compliment the EBSD microstructural analyses, coordinated laser Raman, focused ion beam/transmission electron microscopy imaging and diffraction data, and NanoSIMS N and C tomographic isotopic imaging will be collected. These data will provide further constraints on the formation of diamonds within ureilites.

Timmons M Erickson↗

NASA NTRS1995

The Fluid Processing Apparatus: from Flight Hardware to Electron Micrographs

Since the early years of space biology, a major drawback in spaceflight plant experiments has been the inability to fix specimens in microgravity, relying instead on fixation after return to Earth. As there, it is of a growing interest to look at the effect of microgravity on the structure and the developmental polarity of root graviperceptive cells, or columella cells, and so, it is important to use flight hardware which allows specimen fixation in space therefore avoiding the confounding effects of rapid readaptation to gravity after landing. As part of the Bioserve Space Technologies, a Center for the Commercial Development of Space (CCDS), we now have experiment flight opportunities through the Commercial Generic Bioprocessing Apparatus (CGBA) payload. In this study the Fluid Processing Apparatus (FPA) was used to grow seedlings for a limited period of time prior to fixation of the tissue in a microgravity environment. Upon return to Earth, the samples were processed for electron microscopy. This report describes the microscopic data obtained from the two space flights (STS-54 and STS-60). In both cases, the electron micrographs of the columella cells revealed well preserved cell structure, well defined microtubules, and the presence of calcium precipitates formed by a antimonate precipitation method.

Hilaire, Emmanuel↗

NASA NTRS1978

Characteristics of microcracks in samples from the drill hole Noerdlingen 1973 in the Ries crater, Germany

Samples from the Noerdlingen 1973 drill core contain abundant shock-induced microfractures which exhibit varying amounts of healing and sealing. Many of the microcracks resemble morphologically the open microcracks present in returned lunar samples. Data derived from petrography, scanning electron microscopy, and differential strain analysis indicate that fewer microcracks were formed at greater depths and crack sealing processes are more effective for cracks associated with planar elements. Although the microcracks in the Ries core are now sealed, they are valid analogues of the open shock-induced cracks of lunar rocks and demonstrate that open cracks do form in rocks at depth during a naturally-occurring shock event. The healing of the shock-induced cracks in the Ries core also precludes their use for laboratory measurements of physical properties intended to be used as analogue measurements of lunar samples in situ.

Padovani, E. R.↗

NASA NTRS1985

The Bloomington (LL6) chondrite and its shock melt glasses

The shock melt glasses of the Bloomington LL-group chondrite were examined using electron-beam microscopy and compared with data from studies of other shock melt glasses. Petrologic and mineralogic characterizations were also performed of the samples. The metal contents of the meteorite were almost wholly Ni-rich martensite. The glasses resembled shock melt glasses in L-group chondrites, and were indicative of isochemical melting during one melt phase, i.e., a very simple history.

Dodd, R. T.↗

NASA NTRS2003

Purification process for vertically aligned carbon nanofibers

Individual, free-standing, vertically aligned multiwall carbon nanotubes or nanofibers are ideal for sensor and electrode applications. Our plasma-enhanced chemical vapor deposition techniques for producing free-standing and vertically aligned carbon nanofibers use catalyst particles at the tip of the fiber. Here we present a simple purification process for the removal of iron catalyst particles at the tip of vertically aligned carbon nanofibers derived by plasma-enhanced chemical vapor deposition. The first step involves thermal oxidation in air, at temperatures of 200-400 degrees C, resulting in the physical swelling of the iron particles from the formation of iron oxide. Subsequently, the complete removal of the iron oxide particles is achieved with diluted acid (12% HCl). The purification process appears to be very efficient at removing all of the iron catalyst particles. Electron microscopy images and Raman spectroscopy data indicate that the purification process does not damage the graphitic structure of the nanotubes.

Nanotechnology/methods↗