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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 55 records · Page 3
All sourcesNASA NTRSDOE OSTI
DOE OSTI2013

Effect of graphene on plasmonic metasurfaces at infrared wavelengths

Significant enhancement of infrared transmittance by the presence of a graphene layer on a plasmonic metasurface (PLM) has been demonstrated. PLMs with different configurations were fabricated, and their transmittance with and without graphene was compared. Selective enhancement by graphene occurred at the plasmon resonance wavelength. The degree of enhancement was found to depend on the width of the gap between the periodic metal regions in the PLM. A maximum enhancement of ∼210% was achieved at a wavelength of 10 μm. The ability to achieve such a drastic increase in transmittance at the plasmon resonant wavelength is expected to lead to improvements in the performance of energy collecting devices and optical sensors.

77 NANOSCIENCE AND NANOTECHNOLOGY↗
DOE OSTI2023

Electrical Analysis of Pulsed Laser Annealed Poly-Si: Ga/SiOx Passivating Contacts

In this contribution, we examine Ga hyper-doped poly-Si/SiOx contacts realized by pulsed laser melting (PLM). Here, we use Ga as a novel p-type dopant and B as a conventional dopant to induce non-equilibrium doping using an excimer laser. We perform simulations to visualize the maximum melt depth profiles within the poly-Si, with a goal of distributing dopants close to the tunneling oxide, but at the same time preserving the passivation. Hall measurements show that sheet resistance for B is lower than Ga due to its higher solid solubility limit in Si. After comparing the Hall active dopant concentration with the chemical concentration obtained by SIMS measurement, we show nearly 100% activation B activation reaching 10^21 cm-3, while only ~20% activation for Ga. Nevertheless, we achieve active doping concentrations of Ga in poly-Si six times higher than its solid solubility limit in Si (~10^19 cm-3). We compare our Hall mobilities with values in the literature for c-Si and show that B mobilities in laser-treated poly-Si are close to that of the literature value for B, while Ga mobilities are lower, possibly due to additional scattering channels within grain boundaries and deformed lattice. We also compare our results on PLM samples with conventional furnace annealed samples, and we show much higher percent activation and mobilities. Previously, we showed a low contact resistivity of 35.5 +/- 2.4 m..omega..cm2. Here, we further confirm this result by scanning spreading resistance microscopy and Kelvin force nanoprobe microscopy. We demonstrate that our poly-Si: Ga/nCz contact exhibits large drift and diffusion currents under normal cell operating voltage, which widens the laser processing window for a good metal/poly-Si/c-Si contact.

high-efficiency solar cells↗
DOE OSTI2026

Advancing extreme pulsed lasers through measurements: summary of the pulsed laser metrology workshop

In this report we present consensus findings produced during the pulsed laser metrology (PLM) workshop (Boulder, CO, USA, August 2025). The workshop was a meeting of 35 scientists from private industry, academia, and U.S. government to compile a list of the metrology needs to support extreme pulsed laser development and implementation. We define ‘extreme pulsed lasers’ loosely as those with peak powers above 1 TW or multi-Joule pulse energies. Such lasers are being increasingly used and investigated for use in high energy particle acceleration, short wavelength radiation generation, laser-based fusion, etc. The rapid growth of these fields and the proliferation of extreme lasers for these applications, coupled with the extreme electric fields they generate and relative scarcity of such lasers, presents unique challenges to accuracy in their measurement. The PLM workshop was a two-day event designed to hear from users, developers, and researchers on the current state of optical metrology associated with these extreme pulsed lasers. The goal was to identify the most important measurement challenges limiting development and implementation of these lasers in practical applications. We report here the conclusions and recommendations of this workshop. The hope is that this document will become the first of many iterations which track the status of measurement needs supporting extreme pulsed lasers.

Lasers↗
NASA NTRS1992

Project Columbiad: Mission to the Moon. Book 2, volume 3: Stage configuration designs; volume 4: Program plan

The Earth Orbital Rendezvous (EOR) configuration for the piloted mission is composed of three propulsive elements in addition to the Crew Module (CM): Primary Trans-Lunar Injection (PTLI), Lunar Braking Module (LBM), and Earth Return Module (ERM). The precursor mission is also composed of three propulsive elements in addition to its surface payloads: PTLI, LBM and the Payload Landing Module (PLM). Refer to Volume 1, Section 5.1 and 5.2 for a break-up of the different stages into the four launches. A quick summary is as follows: PTLI is on Launch 1 and 3 while the LBM, PLM, and surface payloads are on Launch 2 and another LBM, ERM, and CM on Launch 4. The precursor mission is designed to be as modular as possible with the piloted mission for developmental cost considerations. The following topics are discussed: launch vehicle description; primary trans-lunar injection stage; lunar braking module; earth return module; crew module; payload landing module; and surface payload description.

Source record↗
NASA NTRS2000

Pulmonary Toxicity Study of Lunar and Martian Dust Simulants Intratracheally Instilled in Mice

NASA is contemplating sending humans to Mars and the Moon for further exploration. The properties of Hawaiian and Californian volcanic ashes allow them to be used to simulate Martian and lunar dusts, respectively. NASA laboratories use these dust simulants to test performance of hardware destined for Martian or lunar environments. Workers in these test facilities are exposed to low levels of these dusts. The present study was conducted to investigate the toxicity of these dust simulants. Particles of respirable-size ranges of lunar simulant (LS), Martian simulant (MS), TiO2 (negative control) and quartz (positive control) were each intratracheally instilled (saline as vehicle) to groups of 4 mice (C57BL, male, 2-3 month old) at a single treatment of 1 (Hi dose) or 0.1 (Lo dose) mg/mouse. The lungs were harvested at the end of 7 days or 90 days for histopathological examination. Lungs of the LS-Lo groups had no evidence of inflammation, edema or fibrosis. The LS-Hi-7d group had mild to moderate acute inflammation, and neutrophilic and lymphocytic infiltration; the LS-Hi-90d group showed signs of chronic inflammation and some fibrosis. Lungs of the MS-Lo-7d group revealed mild inflammation and neutrophilic and lymphocytic infiltration; the MS-Lo-90d group showed mild fibrosis and particle-laden macrophages (PLM). Lungs of the MS-Hi-7d group demonstrated mild to moderate inflammation and large foci of PLM; the MS-Hi-90d group showed chronic mild to moderate inflammation and fibrosis. To mimic the effects of the oxidative and reactive properties of Martian soil surface, groups of mice were exposed to ozone (3 hour at 0.5 ppm) prior to MS dust instillation. Lung lesions in the MS group were more severe with the pretreatment. The results for the negative and positive controls were consistent with the known pulmonary toxicity of these compounds. The overall severity of toxic insults to the lungs were TiO2<LS<MS<Quartz. For the mice in the 90-d study, blood samples were taken for immunotoxicity study. Antinuclear antibodies (such as those against Golgi, kinetichore, and centromere) were detected in serum in a greater extent in mice treated with LS than those with quartz, suggesting that LS, like quartz, has the potential of inducing antoimmune disease.

Lam, Chiu-Wing↗
NASA NTRS2011

Product Lifecycle Management and Sustainable Space Exploration

This slide presentation reviews the use of product lifecycle management (PLM) in the general aerospace industry, its use and development at NASA and at Marshall Space Flight Center, and how the use of PLM can lead to sustainable space exploration.

Caruso, Pamela W.↗
DOE OSTI2026

Oversizing and Part-Load Problems

Oversizing, the common engineering practice of specifying devices with capacity exceeding the actual load requirement, is a widespread practice across virtually all building technologies end-use categories, including HVAC, electrical systems, lighting, appliances, and plug loads. This practice, driven by factors like design uncertainty, institutional pressures, and risk aversion, results in wasted capital investment, control difficulties, and excessive energy consumption due to inefficient part-load operation. Part-load operation, where devices run below maximum capacity, is the dominant operating mode in most energy systems and presents a complex design challenge. Solutions to match output to load fall into three broad categories: constraining the output, adjusting the device’s internal behavior, and linking output to energy storage or other waste-heat reuse applications. The energy implications of part-load are critical, as efficiency often drops sharply as load decreases across a wide diversity of devices. To quantify the extent of this problem, we derive a dimensionless Part-Load Metric (PLM) based on device efficiency and its frequency distribution of operating hours at various output levels. The PLM quantifies the deviation of a device's actual efficiency from its maximum design efficiency. This metric also serves as a measure of "capital inefficiency," enabling engineers to compare the impact of different part-load solutions and providing a unified framework for evaluating performance across various devices and systems.

Meier, Alan↗
DOE OSTI2023

Water Level Data from Wells PLM1 and PLM6 for the East River Watershed, Colorado

This dataset (Williams et al., 2020) contains the original un-QA/QC-ed water level data for PLM1 and PLM6 and has been obsoleted. The data contained within this dataset is not to be used. Refer to Faybishenko et al., 2022 (DOI: 10.15485/1866836) for the latest QA/QC-ed data available via ESS-DIVE.This data set contains water level data for the PLM1 and PLM6 wells. PLM1 and PLM6 are location identifiers used by the Watershed Function SFA project for two groundwater monitoring wells along an elevation gradient located along the lower montane life zone of a hillslope near the Pumphouse location. These wells used to monitor subsurface water and carbon inventories and fluxes at the East River Watershed, Colorado, USA. Complete metadata information on the PLM1 and PLM6 wells are available in the related data package reference Varadharajan C, et al (2020). https://doi.org/10.15485/1660962.Data are reported in .csv files per well. The latitude and longitude of each location are given in a file called locations.csv. These data are used for determining the seasonally dependent flow of groundwater under the PLM hillslope. The downslope flow of groundwater in combination with data on groundwater chemistry can be used to estimate rates of solute export from the hillslope to the floodplain and river.These data products are part of the Watershed Function Scientific Focus Area collection effort to further scientific understanding of biogeochemical dynamics from genome to watershed scales.

54 ENVIRONMENTAL SCIENCES↗
NASA NTRS2015

NASA Work Experience

I have had the opportunity to support the analytical laboratories in chemical analysis of unknown samples, using Optical Microscopy (OM), Polarizing Light Microscopy (PLM), Fourier-Transform Infrared Spectroscopy (FT-IR), Scanning Electron Microscopy with Energy Dispersive Spectroscopy (SEMEDS), and X-ray Powder Diffraction (XPD). I have assisted in characterizing fibers pulled from a spacecraft, a white fibrous residue discovered in a jet refueler truck, brown residue from a plant habitat slated for delivery to the ISS (International Space Station), corrosion on a pipe from a sprinkler, and air filtration material brought back from the ISS. I also conducted my own fiber study in order to practice techniques and further my understanding of background concepts. Furthermore, I had the opportunity to participate in diverse work assignments, where I was assigned to work with other branches of the engineering department for 1-2 days each. The first was in the Materials Science branch where I participated in the construction of the plant habitat intended for use in research aboard the ISS. The second was in the Testing Design branch where I assisted with tensile and hardness testing of over 40 samples. In addition, I have had the privilege to attend multiple tours of the NASA KSC campus, including to the Astronaut Crew Quarters, the VAB (the main area, the Columbia room, and the catwalk), the Visitor Center housing the shuttle Atlantis, the Saturn-V exhibit, the Prototype laboratory, SWAMP WORKS, the Shuttle Landing Facility, the Crawler, and the Booster Fabrication Facility (BFF). Lastly, much of my coursework prepared me for this experience, including numerous laboratory courses with topics diverse as chemistry, physics, and biology.

Florida Tech↗
NASA NTRS2016

Crawler Solids Unknown Analysis

Crawler Transporter (CT) #2 has been undergoing refurbishment to carry the Space Launch System (SLS). After returning to normal operation, multiple filters of the gear box lubrication system failed/clogged and went on bypass during a test run to the launch pad. Analysis of the filters was done in large part with polarized light microscopy (PLM) to identify the filter contaminates and the source of origin.

Polarized Light Microscopy↗
DOE OSTI2013

Death-domain associated protein-6 (DAXX) mediated apoptosis in hantavirus infection is counter-balanced by activation of interferon-stimulated nuclear transcription factors

Hantaviruses are negative strand RNA species that replicate predominantly in the cytoplasm. They also activate numerous cellular responses, but their involvement in nuclear processes is yet to be established. Using human umbilical vein endothelial cells (HUVECs), this study investigates the molecular finger-print of nuclear transcription factors during hantavirus infection. The viral-replication-dependent activation of pro-myelocytic leukemia protein (PML) was followed by subsequent localization in nuclear bodies (NBs). PML was also found in close proximity to activated Sp100 nuclear antigen and interferon-stimulated gene 20 kDa protein (ISG-20), but co-localization with death-domain associated protein-6 (DAXX) was not observed. These data demonstrate that hantavirus triggers PML activation and localization in NBs in the absence of DAXX-PLM-NB co-localization. The results suggest that viral infection interferes with DAXX-mediated apoptosis, and expression of interferon-activated Sp100 and ISG-20 proteins may indicate intracellular intrinsic antiviral attempts.

60 APPLIED LIFE SCIENCES↗
DOE OSTI2014

The influence of chemical composition of aliphatic-aromatic copolyesters on their properties

The chain microstructure and properties of a series of aliphatic-aromatic copolyesters in a range of compositions from 10 to 100% of aromatic components were studied by examining melting and crystallization behaviors, dynamic mechanical response, morphology, wide- (WAXS) and small-angle X-ray scattering (SAXS), and tensile deformation. Chain microstructure was analyzed by {sup 1}H NMR. The results indicate that most of copolyesters used in this study have essentially random distribution of comonomers. Copolyesters with more than 30 mol% of aromatic part crystallize with a crystal structure characteristic for homopolymer poly(butylene terephthalate) (PBT). However, some of the reflections from crystal planes are shifted towards lower diffraction angles as compared to butylene terephthalate homoplymer. The phase transition temperatures decrease with increasing aliphatic content. By means of polarized light microscopy (PLM), small-angle light scattering (SALS) and SAXS, crystallization behavior of a selected aliphatic-aromatic copolyester was further explored. Selected copolyester crystallizes in the form of thin fibrous crystals, few nanometers thick, which is the main factor influencing the depression of its melting temperature.

75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND↗
DOE OSTI2014

Hyperon matter at low densities

It was reported recently that hyperons can be present inside PSRJ1614-2230 compact star. This can be realized only if the strength of the ω-hyperons and φ-hyperons coupling of conventional hyperons coupling constant on the extended relativistic mean field (ERMF) model increase by a factor of 1.5 to 3. In the present work, the mass and radius relation of the neutron star that is calculated by using BSR28 parameter set of ERMF model augmented with maximal coupling strength of the ω-hyperons and φ-hyperons (X=1), is compared to the mass and radius relation of the neutron star that is predicted by the same RMF parameter set but by assuming that hyperons do not exist in the matter (No. Hyp) as well as those by assuming the hyperons coupling constant fulfilled the conventional SU(6) and SU(3) symmetry. The consequences of implementing X=1 prescription are also discussed. The potential depths of hyperons in symmetric nuclear matter (SNM), pure neutron matter (PNM) and pure lambda matter (PLM) based on this parameter set are also calculated by using the X=1, SU (6) and SU (3) prescriptions. The results are compared to those obtained from microscopic models, quark meson coupling model (χ QMM) and the QCD sum rule for finite density (QCD SM) result.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗
DOE OSTI2020

Natural abundance nitrate isotopes from Rifle and the East River Watershed, Colorado

This data package provides data on the natural abundance isotopes of nitrate from various sources, including porewater, stream, and precipitation. The overall purpose of this data package is to complement additional data streams for nitrogen cycling metrics (e.g., riverine inorganic and organic nitrogen measurements) with specific data gleaned from the interpretation of terrestrial and riverine isotope measurements and collectively understand on how nitrogen is cycled around this system. The Rifle and East River are part of the Watershed Function Scientific Focus Area (WFSFA) located in the Upper Colorado River Basin, United States. Collection locations include: Pumphouse (multiple sampling dates), River (upstream/ downstream meander C), Shallow soil lysimeters (hillslope, toeslope, floodplain), Hillslope-floodplain borehole wells (i.e., Pumphouse Lower Montane (PLM) wells), and Potassium chloride(KCL)-extracted soil samples. Copper Creek sampling includes 8x river sample points and two tributaries sampled on Sept. Oct. 2017, July 2018. East River below the Rocky Mountain Biological Laboratory sampling includes 1 access point sampled on July, Sept. Oct. 2017. Rifle floodplain sampling includes well TT03 across multiple collection times over 2014. Data is provided in 5 individual files by location in csv format, or all compiled in Excel format.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2026

Anion Data for the East River Watershed, Colorado (2014-2025)

The anion data for the East River Watershed, Colorado, consist of fluoride, chloride, sulfate, nitrate, and phosphate concentrations collected at multiple, long-term monitoring sites that include stream, groundwater, and spring sampling locations. These locations represent important and/or unique end-member locations for which solute concentrations can be diagnostic of the connection between terrestrial and aquatic systems. Such locations include drainages underlined entirely or largely by shale bedrock, land covered dominated by conifers, aspens, or meadows, and drainages impacted by historic mining activity and the presence of naturally mineralized rock. Developing a long-term record of solute concentrations from a diversity of environments is a critical component of quantifying the impacts of both climate change and discrete climate perturbations, such as drought, forest mortality, and wildfire, on the riverine export of multiple anionic species. Such data may be combined with stream gauging stations co-located at each monitoring site to directly quantify the seasonal and annual mass flux of these anionic species out of the watershed. This data package contains (1) a zip file (anion_data_2014_2025.zip) containing a total of 386 files: 387 data files of anion data from across the Lawrence Berkeley National Laboratory (LBNL) Watershed Function Scientific Focus Area (SFA) which is reported in .csv files per location and a locations.csv (1 file) with latitude and longitude for each location; (2) a file-level metadata (v7_20260901_flmd.csv) file that lists each file contained in the dataset with associated metadata; (3) a data dictionary (v7_20260901_dd.csv) file that contains terms/column_headers used throughout the files along with a definition, units, and data type; and (4) a anion MDL fact sheet (anion_MDLs_202608 in PDF and docx formats). Missing values within the anion data files are noted as either "-9999" or "0.0" for not detectable (N.D.) data. There are a total of 47 locations containing anion data. Update on 2022-06-10: versioned updates to this dataset was made along with these changes: (1) updated anion data for all locations up to 2021-12-31, (2) removal of units from column headers in datafiles, (3) added row underneath headers to contain units of variables, (4) restructure of units to comply with CSV reporting format requirements, and (5) the addition of the file-level metadata (flmd.csv) and data dictionary (dd.csv) were added to comply with the File-Level Metadata Reporting Format. Update on 2022-09-09: Updates were made to reporting format specific files (file-level metadata and data dictionary) to correct swapped file names, add additional details on metadata descriptions on both files, add a header_row column to enable parsing, and add version number and date to file names (v2_20220909_flmd.csv and v2_20220909_dd.csv). Update on 2022-12-20: Updates were made to both the data files and reporting format specific files. Conversion issues affecting ER-PLM locations for anion data was resolved for the data files. Additionally, the flmd and dd files were updated to reflect the updated versions of these files. Available data was added up until 2022-03-14. Update on 2023-08-08: Updates were made to both the data files and reporting format specific files. New available anion data was added, up until 2023-05-19. The file level metadata and data dictionary files were updated to reflect the additional data added. Update on 2024-03-11: Updates were made to both the data files and reporting format specific files. New available anion data was added, up until 2023-09-11. Further, revisions to the data files were made to remove incorrect data points (from 1970 and 2001). The reporting format specific files were updated to reflect the additional data added. Update on 2025-05-15: Updates were made to both the data files and reporting format specific files. New available anion data was added, up until the end of WY2024 (September 30, 2024). International Generic Sample Numbers (IGSNs), when registered, were added to the data files. The reporting format specific files were updated to reflect the additional data added. Update on 2026-09-01: Updates were made to both the data files and reporting format specific files. New available anion data was added, up until the end of WY2025 (September 30, 2025). An anion MDL document was included in this update.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2020

Gap-filled meteorological data (2011-2020) and modeled potential evapotranspiration data from the KCOMTCRE2 WeatherUnderground weather station, from the East River Watershed, Colorado

This dataset is a gap-filled meteorological dataset (years 2011-2020) that includes modeled potential evapotranspiration from a station near the pumphouse on the East River (KCOMTCRE2 WeatherUnderground ) near the top of the ridge at the Pumphouse PLM wells. These datasets are useful as model inputs. The KOMTCRE2 station is located on Mt. Crested Butte in Colorado. More information can be found at: https://www.wunderground.com/dashboard/pws/KCOMTCRE2/table/2020-12-7/2020-12-7/daily. The purpose of this dataset is to use as input to hydrological and flow-reactive transport models as meteorological forcing. One attached file includes metadata files with definitions for all variables and units. Subsequent files include the same time series dataset, but aggregated and gap-filled at different time-stamp intervals. These include 5 minute time-series, 15 minute time-series, 30 minute time-series, 1 hour time-series, daily time-series, and hourly and daily modeled evapotranspiration.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2021

Bedrock weathering rates, reactive nitrogen influxes and effluxes, and nitrous oxide emissions rates from the Pumphouse Hillslope, East River Watershed, Colorado

Atmospheric nitrous oxide contributes directly to global warming, yet models of the nitrogen cycle do not account for bedrock, the largest pool of terrestrial nitrogen, as a source of nitrous oxide. Although it is known that release rates of nitrogen from bedrock are large, there is an incomplete understanding of the connection between bedrock-hosted nitrogen and atmospheric nitrous oxide. Here, we quantify nitrogen fluxes and mass balances at a hillslope underlain by marine shale. We found that at this site bedrock weathering contributes 78% of the subsurface reactive nitrogen, while atmospheric sources (commonly regarded as the sole sources of reactive nitrogen in pristine environments) account for only the remaining 22%. About 56% of the total subsurface reactive nitrogen denitrifies, including 14% emitted as nitrous oxide. The remaining reactive nitrogen discharges in porewaters to a floodplain where additional denitrification likely occurs. We also found that the release of bedrock nitrogen occurs primarily within the zone of the seasonally fluctuating water table and suggest that the accumulation of nitrate in the vadoes zone, often attributed to fertilization and soil leaching, may also include contributions from weathered nitrogen-rich bedrock. Our hillslope study suggests that under oxygenated and moisture-rich conditions, weathering of deep, nitrogen-rich bedrock makes an important contribution to the nitrogen cycle. The data files are in Excel, which can be accessed using Microsoft Office, and consist of many data sets from the Pumphouse Hillslope PLM (Pumphouse Lower Montane) 1, 2, 3, and 4. They include soil to rock (0-10 meters) solid phase minerals and elements compositions; time- and depth-resolved pore-water chemistry and pore-gas compositions; time- and depth-resolved water table depths and water fluxes; subsurface weathering rates; nitrogen influxes and effluxes and mass balance. The attached paper is in a Word document, which can be accessed using Microsoft Office, and in pdf format.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2022

Data used in manuscript "Quantifying Subsurface Flow and Solute Transport in a Snowmelt-recharged Hillslope with Multiyear Water Balance", submitted to Water Resources Research on 5-26-2022

Data in this package were used to calculate subsurface flow and solute (specifically dissolved nitrogen) transport in the Pumphouse Lower Montane (PLM) hillslope. These data are included in separate CSV files associated with each figure presented in the manuscript. The files describe site locations and elevations, weather data (air temperatures and precipitation), modeled evapotranspiration, time dependent groundwater elevations, calculated annual subsurface flow, hydraulic conductivity values, time trends in subsurface flow within different zones, pore water concentrations of total dissolve nitrogen (TDN), rates of TDN transport, soil water matric potentials following snowmelt, soil water contents during drainage, and evapotranspiration calculated by soil water mass balance versus by CLM4 model.

54 ENVIRONMENTAL SCIENCES↗