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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 325 records · Page 18
All sourcesNASA NTRSDOE OSTI
NASA NTRS2004

Analytical Instrument for Determining the Composition of Surface Materials and Ices in the Solar System: Mini-CIDEX to TIDE

Exobiology experiments onboard spacecraft or space probes often require the detection and identification of a wide range of chemical species over vast concentration ranges. These experiments must be carried out under severely limited conditions utilizing minimal resources. The mini-Cometary Ice and Dust Experiment (mini-CIDEX) instrument was developed for the chemical analysis of a cometary environment. It combined a Gas Chromatograph (GC) with a helium-based Ion Mobility Spectrometer (IMS) to fulfill the analytical requirements of a cometary exobiology mission: universal response; ppb sensitivity; low mass, volume, and consumables. Mini-CIDEX has evolved into the Titan Ice and Dust Experiment (TIDE) for the chemical analysis of the surface (liquid and solid) and lower atmosphere of Titan. The complexity of the analyses will be similar to the comet application with a heavier emphasis on organic molecules. TIDE is a component of the Titan Orbiter Aero-Rover Mission (TOAM) proposed to NASA's New Visions Program. Advances to the Mini-CIDEX technology for the Titan application and the analytical capabilities of TIDE will be presented.

Kojiro, Daniel R.↗
DOE OSTI2025

Solid State Solar Thermochemical Fuel (SoFuel) for Long Duration Storage

Efficient thermal storage systems, when coupled with renewable energy, enable the decarbonization of numerous industrial processes requiring high temperature steam or air, and provide a path for seasonal building heating, especially for colder climates. Existing thermal storage systems face a significant challenge due to losses inherent to all high temperature systems. A viable route to long-term storage is to use thermochemical reactions to convert concentrated solar energy to a fuel that is shelf-stable and can be stored at room temperature, thus eliminating losses associated with high temperature storage. The Solid-State Solar Thermochemical Fuel (SoFuel) technology developed by Michigan State University, Oregon State University, and Mississippi State University provides reactors and processes with minimal sensible heat losses and allows storing solar energy as a solid-state fuel at room temperature for long duration. The production of SoFuel occurs within a cylindrical cavity reduction chemical reactor that captures concentrated solar radiation from a solar field. Reactive magnesium manganese oxide (Mg-Mn-O) resides within the cylindrical cavity chemical reactor and undergoes thermal reduction as the temperature exceeds 1350°C. The thermally reduced Mg-Mn-O pellets (the SoFuel) are cooled down through a recuperative process and stored within a bin until used. The SoFuel can directly supply up to 1100C heat to an adjacent power plant for electricity generation or industrial heating. Oxidation of SoFuel pellets occurs in a counter flow reactor and supplies heat to the user for electricity generation or industrial processing, after which the fuel is returned to the concentrating solar field where it is regenerated for re-use. Both reactors can be controlled well using a variety of strategies. With the low cost of the material, its cyclability, and the possibility of using the pelletized with on-sun reactors, or with electricity that would be curtailed, this project offers a viable option of medium- and long-term thermal energy storage.

25 ENERGY STORAGE↗
DOE OSTI2024

Solid State Solar Thermochemical Fuel (SoFuel) for Long Duration Storage

Efficient thermal storage systems, when coupled with renewable energy, enable the decarbonization of numerous industrial processes requiring high temperature steam or air, and provide a path for seasonal building heating, especially for colder climates. Existing thermal storage systems face a significant challenge due to losses inherent to all high temperature systems. A viable route to long-term storage is to use thermochemical reactions to convert concentrated solar energy to a fuel that is shelf-stable and can be stored at room temperature, thus eliminating losses associated with high temperature storage. The Solid-State Solar Thermochemical Fuel (SoFuel) technology developed by Michigan State University, Oregon State University, and Mississippi State University provides reactors and processes with minimal sensible heat losses and allows storing solar energy as a solid-state fuel at room temperature for long duration. The production of SoFuel occurs within a cylindrical cavity reduction chemical reactor that captures concentrated solar radiation from a solar field. Reactive magnesium manganese oxide (Mg-Mn-O) resides within the cylindrical cavity chemical reactor and undergoes thermal reduction as the temperature exceeds 1350°C. The thermally reduced Mg-Mn-O pellets (the SoFuel) are cooled down through a recuperative process and stored within a bin until used. The SoFuel can directly supply up to 1100°C heat to an adjacent power plant for electricity generation or industrial heating. Oxidation of SoFuel pellets occurs in a counter flow reactor and supplies heat to the user for electricity generation or industrial processing, after which the fuel is returned to the concentrating solar field where it is regenerated for re-use. Both reactors can be controlled well using a variety of strategies. With the low cost of the material, its cyclability, and the possibility of using the pelletized with on-sun reactors, or with electricity that would be curtailed, this project offers a viable option of medium- and long-term thermal energy storage.

14 SOLAR ENERGY↗
NASA NTRS1999

The Impact of Anisotropic Error Correlation Modelling

Most data assimilation systems assume isotropic forecast error correlations, but results from two dimensional Kalman Filter experiments indicate that the correlations can be far from isotropic. In this paper we use a simple two-dimensional data assimilation system, which analyses trace chemical species such as ozone, to assess different approaches to modelling the error correlations. We compare assimilation results using isotropic correlations with results obtained using different approaches to modelling anisotropic correlations: first, using correlations based on the concentrations of the trace chemicals, and secondly using an advective correlation model. We show that these relatively cheap ways of modelling anisotropic correlations give objectively better results than using isotropic correlations. We discuss the possible extension of these approaches to a full 3-D meteorological data assimilation system.

Swinbank, R.↗
NASA NTRS2009

Effects of Temperature on Polymer/Carbon Chemical Sensors

Experiments were conducted on the effects of temperature, polymer molecular weight, and carbon loading on the electrical resistances of polymer/carbon-black composite films. The experiment were performed in a continuing effort to develop such films as part of the JPL Electronic Nose (ENose), that would be used to detect, identify, and quantify parts-per-million (ppm) concentration levels of airborne chemicals in the space shuttle/space station environments. The polymers used in this study were three formulations of poly(ethylene oxide) [PEO] that had molecular weights of 20 kilodaltons, 600 kilodaltons, and 1 megadalton, respectively. The results of one set of experiments showed a correlation between the polymer molecular weight and the percolation threshold. In a second set of experiments, differences among the temperature dependences of resistance were observed for different carbon loadings; these differences could be explained by a change in the conduction mechanism. In a third set of experiments, the responses of six different polymer/carbon composite sensors to three analytes (water vapor, methanol, methane) were measured as a function of temperature (28 to 36 C). For a given concentration of each analyte, the response of each sensor decreased with increasing temperature, in a manner different from those of the other sensors.

Manfireda, Allison↗
DOE OSTI2026

Personal and environmental predictors of polycyclic aromatic hydrocarbon exposure identified through repeated silicone wristband sampling

This study integrates quantitative data on personal exposure to polycyclic aromatic hydrocarbons (PAHs) in 162 silicone wristbands with demographics, behavioral information, and housing characteristics to explore contributions to residential exposure in a superfund-adjacent community over the course of a year. Forty-six residents completed questionnaires and wore silicone wristbands as personal passive samplers for seven consecutive days on up to four separate occasions in alternating months between November 2022 and June 2023. It was hypothesized that individual behaviors and housing characteristics are sources of dependence and correlation between personal PAH exposures. 50 PAHs were detected at least once, 17 of which were alkylated PAHs. Exposure to PAHs of similar molecular weight was often correlated, notably between naphthalenes (2-rings) and higher molecular weight PAHs (3 or more rings). Generalized linear mixed models identified flooring type, participant age, and sampling month as important predictors of increased PAH exposure, and flooring type, and use of wood stoves or heavy machinery as predictors of increased naphthalene exposure relative to higher molecular weight PAHs. Individual chemical models based on concentration data and detection frequencies corroborated these findings across multiple PAHs. We demonstrate that personal exposure is not static and the degree of variability in personal exposure is individual. Hence, identification of influential exposure factors through repeated measures of chemical exposure and characterization of variability in personal exposure as performed in this study, is important in the development of exposure mitigation strategies.

Bonner, Emily↗
DOE OSTI2021

Solvent-induced electrochemistry at an electrically asymmetric carbon Janus particle

Chemical doping through heteroatom substitution is often used to control the Fermi level of semiconductor materials. Doping also occurs when surface adsorbed molecules modify the Fermi level of low dimensional materials such as carbon nanotubes. A gradient in dopant concentration, and hence the chemical potential, across such a material generates usable electrical current. This opens up the possibility of creating asymmetric catalytic particles capable of generating voltage from a surrounding solvent that imposes such a gradient, enabling electrochemical transformations. In this work, we report that symmetry-broken carbon particles comprised of high surface area single-walled carbon nanotube networks can effectively convert exothermic solvent adsorption into usable electrical potential, turning over electrochemical redox processes in situ with no external power supply. The results from ferrocene oxidation and the selective electro-oxidation of alcohols underscore the potential of solvent powered electrocatalytic particles to extend electrochemical transformation to various environments.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2024

Acid–base concentration swing for direct air capture of carbon dioxide

This work demonstrates the first experimental evidence of the acid–base concentration swing (ABCS) for direct air capture of CO 2 . This process is based on the effect that concentrating particular acid–base chemical reactants will strongly acidify solution, through Le Chatelier's principle, and result in outgassing absorbed CO 2 . After collecting the outgassed CO 2 , diluting the solution will result in a reversal of the acid–base reaction, basifying the solution and allowing for atmospheric CO 2 absorption. The experimental study examines a system that includes sodium cation as the alkalinity carrier, boric acid, and a polyol complexing agent that reversibly reacts with boric acid to strongly acidify solution upon concentration. Though the tested experimental system faces absorption rate and water capacity limitations, the ABCS process described here provides a basis for further process optimization. A generalized theoretical ABCS reaction framework is developed and different reaction orders and conditions are studied mathematically. Higher order reactions yield favorable cycle output results, reaching volumetric cycle capacity above 50 mM for third-order and 80 mM for fourth-order reactions. Optimal equilibrium constants are determined in order to guide alternative chemical searches and synthetic chemistry design targets. There is a substantial energetic benefit for reaction orders above the first, with second- and third-order ABCS cycles exhibiting a thermodynamic minimum work for the concentrating and outgassing steps around 150 kJ per mole of CO 2 . A significant advantage of the ABCS is that it can be driven through well-developed and widely-deployed desalination technologies, such as reverse osmosis, with opportunities for energy recovery when recombining the concentrated and diluted streams, and extraction can occur directly from the liquid phase upon vacuum application.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2025

Chemical Activation of Frontal Ring-Opening Metathesis Polymerization

In this study, we present an innovative approach to frontal ring-opening metathesis polymerization (FROMP) through chemical activation. By locally concentrating Grubbs-type initiators, we accelerate exothermic polymerization at the activation site. Sufficient thermal energy initiates a polymerization front that travels through the remainder of the sample even with reduced initiator concentrations in the bulk resin. Initiation location and timing are controlled by adjusting the initiator reactivity, the properties of the transport solvent, and the air–resin interface. Our technique enables multipoint front activation, either through synchronized injection or by timing the relative reactivity of various initiators. This accessible method of chemical activation enables on-demand production of polymer and composite materials using only the thermal energy generated by the reaction, removing the need for external power sources and enabling deployment in remote or infrastructure-limited environments.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2022

Per- and Polyfluoroalkyl Substances: A Preliminary Evaluation of Groundwater Contamination in the Western States

Per- and Polyfluoroalkyl Substances (PFAS) are a manufactured group of chemicals that have been used since the 1940s. PFAS break down very slowly and studies show that exposure to these chemicals may cause negative reproductive effects, developmental delays in children, increased risk of some cancers, and interference with the body’s natural hormones. On June 15, 2022, EPA issued interim updated drinking water health advisories for the two most widely studied PFAS, perfluorooctanoic acid (PFOA) and perfluorooctane sulfonic acid (PFOS). The concentrations for the health advisory limits are 0.004 parts per trillion (ppt) and 0.02 ppt respectively. Because data is often reported in combined PFOA and PFOS concentrations, and for ease of data visualization, concentrations of the two chemicals will be discussed as a single, summed value and will be compared to the combined health advisory limits of 0.024 ppt. Due to the recently published near-zero health advisory limits and the known negative health effects, a map of estimated PFAS groundwater contamination was created using ArcGIS Pro and geostatistical tools to inform the public and determine which regions are most at-risk.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2022

Organic Evaporation and Oxidation Testing in Support of Hanford Sample-and-Send

The Hanford site has approximately 56 million gallons of radioactive mixed waste stored in 177 underground storage tanks. The Hanford Waste Treatment and Immobilization Plant (WTP) is being built to treat and immobilize the tank waste. The baseline method for immobilization of Low Activity Waste (LAW) through the WTP is vitrification, but additional immobilization capacity is needed to supplement the initial LAW melters. An alternative cementitious waste form is being investigated for that future immobilization method to supplement vitrification. However, one impediment to a cementitious waste form is the presence of Land Disposal Restricted (LDR) organic chemicals in tank waste. This work evaluates potential avenues to eliminate that impediment to permit possible use of a cementitious waste form and work towards a decision whether additional LDR organic pretreatment would be required. Savannah River National Laboratory (SRNL) performed testing using simulants to examine evaporation as a method to remove some prevalent organics from LAW. Spiking the caustic LAW simulant with selected regulated organic chemicals found one that clearly decomposes because of caustic instability. Oxidation testing of other organic chemicals found some LDR organics degrade as desired and others are stable in the presence of peroxide and permanganate. In addition to studies with simulants, a literature review was performed to evaluate radiological stability of LDR organics. Descriptions of the experimental details, equipment, and results are included in this report. Evaporation testing consisted of preparing the LAW simulant, spiking that simulant with organic chemicals, and evaporating the mixture via differential distillation. The apparatus was a laboratory-scale vacuum evaporator operated at 60 ±5 torr absolute (vacuum evaporation) and also at atmospheric pressure. The LAW simulant represented the liquid expected to be retrieved from the Hanford tank farms at approximately 4.0 M [Na + ] total sodium ion concentration. The concentration of the organic chemicals added was significantly higher than typically found in the tank waste samples since the higher levels were necessary to assist in analytical measurement and tracking of the spiked species. Organic chemicals were chosen for the work with a consideration of how their volatility compares with that of methanol. This was done by comparing the ratio of the pure water Henry’s law coefficient (K h ) of methanol to that of the compound in question (hereafter termed the K h ratio), where ratios above unity indicated less volatility than methanol. Methanol was chosen because it is a common regulated chemical with relatively low volatility but which has been removed by evaporation in previous laboratory work. While organic separation results depend on evaporator design, laboratory experiments verified that organic partitioning to the overhead condensate stream by evaporation is a practical process. The work reported here found difficulties in quantitative analysis of the organic chemicals in aqueous samples. Most of the time there was insufficient analysis to close a mass balance for evaporator runs, but qualitative evidence of carryover was obtained. The methods were also able to show whether organic chemicals were susceptible or resistant to solution oxidation in permanganate or hydrogen peroxide tests.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2025

Sample screening of uranium ore concentrates using portable spectrophotometers: investigating the correlation between visible colors and chemical signatures

A research collaboration between the Japan Atomic Energy Agency and the Department of Energy’s National Nuclear Security Administration examined nuclear forensic signatures and analytical methods for tracing the origins of uranium ore concentrates (UOCs). Here, this study focuses on utilizing portable spectrophotometers capable of reflectance measurements in the visible light spectrum as a potential rapid screening tool for nuclear forensics analysis. Unlike laboratory-based near-infrared spectroscopy or digital image analysis, this research investigated the potential to correlate visible color measurements with key nuclear forensics signatures using seven types of UOC samples with known origins and three UOC certified reference materials. Results demonstrated that distinct color groups, quantified using CIELAB values, correlated with major uranium compounds. Furthermore, the findings indicated that trace elements can influence the UOC colors, providing additional insights into material characteristics. Although this approach requires further validation across a broader range of UOC species, this study demonstrated that simple colorimetric analysis using visible spectrophotometry, which does not require complex sample preparation or data processing, can serve as a practical and novel rapid tool for preliminary screening and attribution in nuclear forensics investigations.

and nuclear chemistry↗
NASA NTRS2024

Terrestrial Ages and Pairing of Howardites, Eucrites and Diogenites From the Miller Range Icefields, Antarctica

In the past 45 years, the US Antarctic Meteorite (ANSMET) program has recovered more than 22,000 meteorites from more than 50 individual meteorite stranding areas. Although the Antarctic meteorite collection is dominated by ordinary chondrites which represent 80-90% of the recovered samples, it also contains many achondrites, including howardites, eucrites and diogenites, which are collectively known as HED meteorites. A challenge for the Antarctic meteorite collection is to identify paired fragments that belong to the same fall. Eight ANSMET field sea-sons at the Miller Range Icefields (MIL), a series of blue ice fields about 40 km long and 10-20 km wide, have yielded more than 3000 meteorites including 56 HEDs. At least three possible pairing groups (with 3-10 members each) were initially identified among the MIL diogenites and one each among the howardites and eucrites. Since many HED meteorites are heterogeneous breccias, pairing identifications based on cm-sized samples is difficult and other independent evidence is needed to verify these proposed pairings, as was shown for several Antarctic howardite pairing-groups. Here we re-examine pairings of HED’s from the Miller Range Icefields, using multiple lines of evidence, including texture/petrography, chemical composition, cosmogenic radionuclides and find locations. Due to the heterogeneous nature of HED meteorites, we will not only consider pairings strictly among the three HED groups, but will also consider pairing of howardites with brecciated eucrites or brecciated diogenites if the cosmogenic nuclides, texture and chemical compositions support this. The concentrations of cosmogenic radionuclides in meteorites are a function of the cosmic-ray exposure (CRE) age, shielding conditions (size and irradiation depth), chemical composition, as well the terrestrial age of the meteorite sample. Since the production rates of cosmogenic nuclides as a function of meteoroid size, depth and composition are well understood [6], their measured concentrations can be used to determine which meteorites belong to the same fall even if the chemical composition of the samples show significant variations. We selected 28 of the 56 HED samples from the MIL collection, including 12 diogenites, 8 howardites and 8 brecciated eucrites to investigate pairing relationships.

howardite↗
DOE OSTI2026

Chemical beneficiation of cobaltiferous pyrite: a thermodynamic and parametric study

Despite ongoing efforts to identify substitute materials, cobalt remains indispensable for the production of rechargeable batteries essential to the global energy transition. Currently, most cobalt is sourced as a by-product of nickel and copper extraction from politically and ethically unstable regions. To address this vulnerability, certain primary cobalt deposits—where cobalt occurs within the crystal lattice of pyrite (FeS 2 )—have been identified as potential alternatives. Nonetheless, conventional beneficiation methods have proven largely ineffective for the potential processing of these minerals. This study investigated the thermal decomposition of cobaltiferous pyrite contained in flotation concentrates as a subsequent chemical beneficiation stage aimed at (i) selectively removing sulfur to further increase cobalt grades and (ii) producing a ferromagnetic product suitable for downstream magnetic separation. A thermodynamic analysis was first conducted to evaluate the feasibility of the decomposition reactions and the temperature-dependent evolution of sulfur species. A parametric experimental study then assessed the influence of temperature, residence time, and gas flow rate under N 2 and CO 2 atmospheres. Under the most favorable experimental conditions tested (650 °C, 15 min), cobalt grades increased by up to 15% with negligible cobalt losses and the co-production of high-purity sulfur (>95%). Magnetic separation of the resulting calcine yielded a final concentrate containing 2.09% cobalt at 82.5% recovery, representing a 16–74% improvement over previous baseline studies on similar feedstocks.

Beneficiation↗
DOE OSTI2025

Data for Identifying the best high-biomass sorghum hybrids based on biomass yield potential and feedstock quality affected by nitrogen fertility management under various environments

Data were collected from agronomy fields in Urbana and Ewing, IL, during the 2022 and 2023 growing seasons. The dataset includes dry biomass yield, nitrogen, phosphorus, and potassium concentrations and removals, and chemical composition elements (cellulose, hemicellulose, lignin, and soluble fractions) for 13 high-biomass sorghum hybrids. data_sharing.xlsx contains 20 columns and 104 rows. Below is the explanation of all variables in the file: Year: 2022; 2023 Location: Urbana, IL; Ewing, IL N rate (kg-N/ha): 0; 112 Hybrid #: H1-H13 Pedigree: Pedigree for 13 hybrids Dry biomass yield (Mg/ha): Aboveground dry biomass yield N (g/kg): Nitrogen concentration in plant tissue P (g/kg): Phosphorus concentration in plant tissue K (g/kg): Potassium concentration in plant tissue N (kg/ha): Nitrogen removal by aboveground biomass P (kg/ha): Phosphorus removal by aboveground biomass K (kg/ha): Potassium removal by aboveground biomass Cellulose (g/kg): Cellulose concentration in plant tissue Hemicellulose (g/kg): Hemicellulose concentration in plant tissue Lignin (g/kg): Lignin concentration in plant tissue Soluble (g/kg): Soluble concentration in plant tissue Cellulose (Mg/ha): Cellulose content in aboveground biomass Hemicellulose (Mg/ha): Hemicellulose content in aboveground biomass Lignin (Mg/ha): Lignin content in aboveground biomass Soluble (Mg/ha): Soluble content in aboveground biomass

environmental adaptability↗
DOE OSTI2026

High Time Resolution Modelled and Measured New Particle Formation Rates During the 2023 Pittsburgh, PA Campaign

Particle size distributions are used to calculate nucleation rates during new particle formation (NPF). However, the low time resolution and poor sensitivity of instruments deployed to observe particle size distributions can lead to inaccurate estimates of nucleation rates. We calculated nucleation rates in Pittsburgh, PA from particle size distributions measured with the new high time resolution Condensation Particle Counters For Atmospheric Rapid Measurements (CPC FARM) and from gas precursor concentrations measured with a chemical ionization mass spectrometer. The CPC FARM nucleation rates were calculated by examining the appearance rate of particles in the smallest size bin at 1.6 nm. The nucleation rate of 1.6 nm determined every second resulted in positive and negative rates, indicating the influence of inhomogeneous mixing and advection of precursor gases and clusters. These effects are not currently considered when estimating nucleation rates from measurements. The nucleation rates from the CPC FARM were compared to the nucleation rates determined from a transient acid‐base reaction model using measured sulfuric acid concentration, strong base concentrations, and CPC detection efficiencies. The transient form of the model allowed the advection of heterogeneously mixed precursors to influence the nucleation rate. Good agreement between particle and gas‐based nucleation rates is observed during sulfuric acid‐driven NPF events. This study demonstrates that high time resolution measurements of short‐lived and rapidly formed particles are needed to accurately capture nucleation rates, which are likely influenced by advection of nucleation precursors and clusters in heterogeneous environments such as urban areas.

Cheng, D. [Carnegie Mellon Univ., Pittsburgh, PA (↗