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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 1,387 records · Page 77
All sourcesNASA NTRSDOE OSTI
NASA NTRS2020

NASA Engineering and Safety Center Technical Bulletin No. 20-08: Assessment of Ketazine Derived High Purity Hydrazine for Spacecraft Propellant Systems

Hydrazine and its derivatives have dominated the class of hypergolic liquid propellants for bipropellant propulsion systems in rockets such as the Titan, MX Missile, and Ariane; it has also been widely utilized as a monopropellant in auxiliary power units and in thrusters for altitude and in-orbit control of satellites and spacecraft. With continued use of hydrazine in current and future spacecraft and payloads, it is necessary to understand the historical and current states of synthesis for the commodity and possible implications that may arise from changes in production processes for the United States stock.

Ketazine↗
DOE OSTI2020

Multi-phase covetic and methods of synthesis thereof

There are provided methods and systems for creating multi-phase covetics. For example, there is provided a process for making a composite material. The process includes forming a multi-phase covetic. The forming includes heating a melt including a metal in a molten state and a carbon source to a first temperature threshold to form metal-carbon bonds. The forming further includes subsequently heating the melt to a second temperature threshold, the second temperature threshold being greater than the first temperature threshold. The second temperature threshold is a temperature at or above which ordered multi-phase covetics form in the melt.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Multi-phase covetic and methods of synthesis thereof

There are provided methods and systems for creating multi-phase covetics. For example, there is provided a process for making a composite material. The process includes forming a multi-phase covetic. The forming includes heating a melt including a metal in a molten state and a carbon source to a first temperature threshold to form metal-carbon bonds. The forming further includes subsequently heating the melt to a second temperature threshold, the second temperature threshold being greater than the first temperature threshold. The second temperature threshold is a temperature at or above which ordered multi-phase covetics form in the melt.

36 MATERIALS SCIENCE↗
DOE OSTI2021

Kilonovae Across the Nuclear Physics Landscape: The Impact of Nuclear Physics Uncertainties on r-process-powered Emission

Merging neutron stars produce “kilonovae”—electromagnetic transients powered by the decay of unstable nuclei synthesized via rapid neutron capture (the r-process) in material that is gravitationally unbound during inspiral and coalescence. Kilonova emission, if accurately interpreted, can be used to characterize the masses and compositions of merger-driven outflows, helping to resolve a long-standing debate about the origins of r-process material in the Universe. We explore how the uncertain properties of nuclei involved in the r-process complicate the inference of outflow properties from kilonova observations. Using r-process simulations, we show how nuclear physics uncertainties impact predictions of radioactive heating and element synthesis. For a set of models that span a large range in both predicted heating and final abundances, we carry out detailed numerical calculations of decay product thermalization and radiation transport in a kilonova ejecta with a fixed mass and density profile. The light curves associated with our models exhibit great diversity in their luminosities, with peak brightness varying by more than an order of magnitude. We also find variability in the shape of the kilonova light curves and their color, which in some cases runs counter to the expectation that increasing levels of lanthanide and/or actinide enrichment will be correlated with longer, dimmer, redder emission.

73 NUCLEAR PHYSICS AND RADIATION PHYSICS↗
DOE OSTI2026

NGEE Arctic Integrated Modeling (IM2): Improved subgrid hillslope hydrologic connectivity

This data product represents the integration of new code capability for arctic tundra hillslope hydrologic processes into the Energy Exascale Earth System Model (E3SM), through the E3SM Land Model (ELM) component. This code integration is the result of collaborative effort between the NGEE Arctic project and the E3SM project. The current ELM represents water movement primarily through vertical processes, such as precipitation, canopy interception, evaporation, infiltration, and soil water movement. Lateral water movement—such as surface runoff, subsurface flow, and river transport—plays a significant role in the hydrological cycle, especially in regions with varied topography. While E3SM includes a runoff routing component representing water transport in the river network, the lateral transport of water at the subgrid scale within the land model has previously not been taken into account. With the recent development of topographic units within the ELM subgrid data structure, there is an opportunity to simulate hillslope hydrologic connectivity by introducing water transport along topographic gradients. We expect that more realistic representation of hillslope hydrologic processes will lead to improved predictions of both soil water content and river network flows. Lateral transport of water at and near the surface is represented as a sub-grid process in this new code development. Water is tracked as it moves from higher to lower elevations within a gridcell. This capability uses the nested hierarchical sub-grid scheme within ELM to connect water fluxes from sub-grid elements with higher elevation to those with lower elevation. This data record consists of a single document (pdf format) that describes the theoretical basis for the hillslope hydrology processes added to ELM, and describes the modifications made to the ELM code. The Methods section of this metadata record includes a link to the public E3SM code repository where the exact code modifications as integrated in E3SM can be accessed. The Next-Generation Ecosystem Experiments: Arctic (NGEE Arctic), was a research effort to reduce uncertainty in Earth System Models by developing a predictive understanding of carbon-rich Arctic ecosystems and feedbacks to climate. NGEE Arctic was supported by the Department of Energy's Office of Biological and Environmental Research. The NGEE Arctic project had two field research sites: 1) located within the Arctic polygonal tundra coastal region on the Barrow Environmental Observatory (BEO) and the North Slope near Utqiagvik (Barrow), Alaska and 2) multiple areas on the discontinuous permafrost region of the Seward Peninsula north of Nome, Alaska. Through observations, experiments, and synthesis with existing datasets, NGEE Arctic provided an enhanced knowledge base for multi-scale modeling and contributed to improved process representation at global pan-Arctic scales within the Department of Energy's Earth system Model (the Energy Exascale Earth System Model, or E3SM), and specifically within the E3SM Land Model component (ELM).

Thornton, Peter E [ORNL] (ORCID:0000000247595158)↗
DOE OSTI2024

Titanium Dioxide Nanomaterial Ink Production Through Laser Ablation Synthesis in Solution for Printed Electronics Applications

Flexible and printed electronics have become increasingly popular as they make possible the production of flexible, low-cost, multifunction devices that are unachievable through traditional manufacturing methods. The printed films are significantly impacted and thus limited by the existing ink production process. Herein, an alternate technique of generating high-quality titanium dioxide (TiO 2 ) nanoparticle ink compatible with aerosol jet printing using laser ablation synthesis in solution (LASiS) is showcased. Dynamic light scattering data and transmission electron microscopy confirm the particle size distribution. UV–vis measurements are performed, and the Beer–Lambert relationship is used to determine the concentration of the generated ink. The inks generated at two different repetition rates are compared: 200 kHz and 1 MHz. X-Ray diffraction analysis of the aerosol jet printed thin film post-thermal sintering confirms the grain size and phase purity of the printed thin films. This work demonstrates the effectiveness of the LASiS technique in producing printable nanoparticle inks with little-to-no postprocessing.

36 MATERIALS SCIENCE↗
DOE OSTI2022

Digestion processes and elemental analysis of oxide and sulfide solid electrolytes

Detailed elemental analysis is essential for a successful development and optimization of material systems and synthesis methods. This is especially relevant for Li- and Na-containing compounds, found in state-of-the-art and next-generation battery systems. Their materials’ properties and thus the final device performance strongly depend on the crystal structure, the stoichiometry, and defect chemistry, e.g., influencing charge carrier concentration and activation energies for vacancy transport. However, a detailed quantitative analysis of light elements in a heavy matrix, featuring a broad range of solubilities and vapor pressures, is often difficult and associated with large uncertainties and thus neglected in favor of just reporting the stoichiometry as “weighed in.” Here, in this work, we report several approaches to digest and dissolve various oxide and sulfide-based materials, used in next-generation Li batteries, for elemental analysis via optical emission spectroscopy. These include the most common solid electrolytes Li-La-Ti–O, a perovskite material (LLTO), and Li-La-Zr-O which has garnet structure (LLZO). Additionally, a facile thermal digestion process is reported for a surrogate sulfide solid electrolyte (Na 2 S). The digestion procedures reported here are suitable for almost any laboratory environment and, when applied, will improve understanding of the synthesis-structure–property correlations needed to advanced batteries with all solid-state configurations.

Malkowski, Thomas F.↗
DOE OSTI2025

Novel Superionic Na Conductors for Solid‐State Na batteries: Materials and Interface

This project aims to advance the fundamental understanding on how the cation or anion doping influence on the crystal structure, phase stability and ion transport of novel Na superionic conductors. Specifically, we focus on the Na 3-x A x SbS 4-y X y family solid electrolytes (A: cation dopant, X: anion dopant), a class of promising materials for all-solid-state sodium batteries owing to their high ionic conductivity and compositional tunability. By integrating materials synthesis, neutron scattering, and electrochemical characterization and theoretical simulations, this project sees to elucidate 1) how does the synthesis approaches (solid-state reaction, low-temperature reaction) on the phase purity and doping process; 2) how chemical doping (A: cation dopants such as Sn; X: anion dopants such as Se, F) modulate lattice dynamics and Na+ migration as well as interface stability toward Na metal. Specifically, this project’s proposed technology involves three objectives: (1) synthesize novel Na-ion conductors (anion or cation doped Na 3 SbS 4 ) with high phase purity and examine their structural features (e.g., phase stability); (2) understand Na-ion conductive properties of new Na-ion conductors through a combination of experimental characterizations and theoretical simulations; (3) investigate the interface stability of novel Na superionic conductors with electrode materials in solid-state Na batteries. These objectives will be achieved through combined experimental synthesis/characterizations and computational approaches. The obtained knowledge will provide a comprehensive synthesis-structure-property correlation, enabling the rational design of novel solid-state conductors with excellent conductivity and stability.

25 ENERGY STORAGE↗
DOE OSTI2024

Carbon Negative Synthesis of Amino Acids Using a Cell-Free-Based Biocatalyst

Biological systems can directly upgrade carbon dioxide (CO 2 ) into chemicals. The CO 2 fixation rate of autotrophic organisms, however, is too slow for industrial utility, and the breadth of engineered metabolic pathways for the synthesis of value-added chemicals is too limited. Biotechnology workhorse organisms with extensively engineered metabolic pathways have recently been engineered for CO 2 fixation. Yet, their low carbon fixation rate, compounded by the fact that living organisms split their carbon between cell growth and chemical synthesis, has led to only cell growth with no chemical synthesis achieved to date. Here, we engineer a lysate-based cell-free expression (CFE)-based multienzyme biocatalyst for the carbon negative synthesis of the industrially relevant amino acids glycine and serine from CO 2 equivalents–formate and bicarbonate–and ammonia. The formate-to-serine biocatalyst leverages tetrahydrofolate (THF)-dependent formate fixation, reductive glycine synthesis, serine synthesis, and phosphite dehydrogenase-dependent NAD(P)H regeneration to convert 30% of formate into serine and glycine, surpassing the previous 22% conversion using a purified enzyme system. We find that (1) the CFE-based biocatalyst is active even after 200-fold dilution, enabling higher substrate loading and product synthesis without incurring additional cell lysate cost, (2) NAD(P)H regeneration is pivotal to driving forward reactions close to thermodynamic equilibrium, (3) balancing the ratio of the formate-to-serine pathway genes added to the CFE is key to improving amino acid synthesis, and (4) efficient THF recycling enables lowering the loading of this cofactor, reducing the cost of the CFE-based biocatalyst. To our knowledge, this is the first synthesis of amino acids that can capture CO 2 equivalents for the carbon negative synthesis of amino acids using a CFE-based biocatalyst. Looking ahead, the CFE-based biocatalyst process could be extended beyond serine to pyruvate, a key intermediate, to access a variety of chemicals from aromatics and terpenes to alcohols and polymers.

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

Coupling reduced‐order modeling and coarse‐grained CFD‐DEM to accelerate coal gasifier simulation and optimization

Abstract High fidelity three‐dimensional (3‐D) numerical simulations of commercial‐scale coal gasifiers are very time consuming and expensive. This article proposes a reduced‐order modeling approach that uses quasi one‐dimensional (1‐D) CFD–DEM simulation results to serve as an accurate initial condition for the 3‐D simulation, which significantly shortens the physical time from several hours to minutes to achieve steady states. The 3‐D simulation employs a previously validated coarse‐grained CFD‐DEM approach, which further accelerates the simulation. Both 1‐D and 3‐D simulations adopt a particle shrinkage scheme to correctly account for the particle volume change due to chemical reaction and thus provides an accurate bed height. Comparison with available experimental measurements of the bed temperature and synthesis gas composition is used to validate the simulation. The final syngas composition and flowrates are strongly affected by the fuel or gasification agent rate and process operating conditions as expected. This approach is then used to optimize two important operating conditions (air and steam flows) to achieve specific gasifier performance goals for the production of Fischer–Tropsch synthesis gas and production of fuel gas for gas turbines.

Yu, Jia↗
DOE OSTI2020

Roadmap on multiscale materials modeling

Modeling and simulation is transforming modern materials science, becoming an important tool for the discovery of new materials and material phenomena, for gaining insight into the processes that govern materials behavior, and, increasingly, for quantitative predictions that can be used as part of a design tool in full partnership with experimental synthesis and characterization. Modeling and simulation is the essential bridge from good science to good engineering, spanning from fundamental understanding of materials behavior to deliberate design of new materials technologies leveraging new properties and processes. This Roadmap presents a broad overview of the extensive impact computational modeling has had in materials science in the past few decades, and offers focused perspectives on where the path forward lies as this rapidly expanding field evolves to meet the challenges of the next few decades. The Roadmap offers perspectives on advances within disciplines as diverse as phase field methods to model mesoscale behavior and molecular dynamics methods to deduce the fundamental atomic-scale dynamical processes governing materials response, to the challenges involved in the interdisciplinary research that tackles complex materials problems where the governing phenomena span different scales of materials behavior requiring multiscale approaches. The shift from understanding fundamental materials behavior to development of quantitative approaches to explain and predict experimental observations requires advances in the methods and practice in simulations for reproducibility and reliability, and interacting with a computational ecosystem that integrates new theory development, innovative applications, and an increasingly integrated software and computational infrastructure that takes advantage of the increasingly powerful computational methods and computing hardware.

36 MATERIALS SCIENCE↗
DOE OSTI2021

Solid-Binding Proteins: Bridging Synthesis, Assembly, and Function in Hybrid and Hierarchical Materials Fabrication

There is considerable interest in the development of hybrid organic–inorganic materials because of the potential for harvesting the unique capabilities that each system has to offer. Proteins are an especially attractive organic component owing to the high amount of chemical information encoded in their amino acid sequence, their amenability to molecular and computational (re)design, and the many structures and functions they specify. Genetic installation of solid-binding peptides (SBPs) within protein frameworks affords control over the position and orientation of adhesive and morphogenetic segments, and a path toward predictive synthesis and assembly of functional materials and devices, all while harnessing the built-in properties of the host scaffold. Furthermore, we review the current understanding of the mechanisms through which SBPs bind to technologically relevant interfaces, with an emphasis on the variables that influence the process, and highlight the last decade of progress in the use of solid-binding proteins for hybrid and hierarchical materials synthesis.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
NASA NTRS1995

Optimal Full Information Synthesis for Flexible Structures Implemented on Cray Supercomputers

This paper considers an algorithm for synthesis of optimal controllers for full information feedback. The synthesis procedure reduces to a single linear matrix inequality which may be solved via established convex optimization algorithms. The computational cost of the optimization is investigated. It is demonstrated the problem dimension and corresponding matrices can become large for practical engineering problems. This algorithm represents a process that is impractical for standard workstations for large order systems. A flexible structure is presented as a design example. Control synthesis requires several days on a workstation but may be solved in a reasonable amount of time using a Cray supercomputer.

Lind, Rick↗
DOE OSTI2021

Controlled Fabrication of Quality ZnO NWs/CNTs and ZnO NWs/Gr Heterostructures via Direct Two-Step CVD Method

A novel and advanced approach of growing zinc oxide nanowires (ZnO NWs) directly on single-walled carbon nanotubes (SWCNTs) and graphene (Gr) surfaces has been demonstrated through the successful formation of 1D–1D and 1D–2D heterostructure interfaces. The direct two-step chemical vapor deposition (CVD) method was utilized to ensure high-quality materials’ synthesis and scalable production of different architectures. Iron-based universal compound molecular ink was used as a catalyst in both processes (a) to form a monolayer of horizontally defined networks of SWCNTs interfaced with vertically oriented ZnO NWs and (b) to grow densely packed ZnO NWs directly on a graphene surface. We show here that our universal compound molecular ink is efficient and selective in the direct synthesis of ZnO NWs/CNTs and ZnO NWs/Gr heterostructures. Heterostructures were also selectively patterned through different fabrication techniques and grown in predefined locations, demonstrating an ability to control materials’ placement and morphology. Several characterization tools were employed to interrogate the prepared heterostructures. ZnO NWs were shown to grow uniformly over the network of SWCNTs, and much denser packed vertically oriented ZnO NWs were produced on graphene thin films. Such heterostructures can be used widely in many potential applications, such as photocatalysts, supercapacitors, solar cells, piezoelectric or thermal actuators, as well as chemical or biological sensors.

77 NANOSCIENCE AND NANOTECHNOLOGY↗
NASA NTRS2014

The Utilization of Urine Processing for the Advancement of Life Support Technologies

The success of long-duration missions will depend on resource recovery and the self-sustainability of life support technologies. Current technologies used on the International Space Station (ISS) utilize chemical and mechanical processes, such as filtration, to recover potable water from urine produced by crewmembers. Such technologies have significantly reduced the need for water resupply through closed-loop resource recovery and recycling. Harvesting the important components of urine requires selectivity, whether through the use of membranes or other physical barriers, or by chemical or biological processes. Given the chemical composition of urine, the downstream benefits of urine processing for resource recovery will be critical for many aspects of life support, such as food production and the synthesis of biofuels. This paper discusses the beneficial components of urine and their potential applications, and the challenges associated with using urine for nutrient recycling for space application.

Resource Recovery↗
DOE OSTI2023

Solutions Are the Problem: Ordered Two-Dimensional Covalent Organic Framework Films by Chemical Vapor Deposition

Covalent organic frameworks (COFs) are a promising class of crystalline polymer networks that are useful due to their high porosity, versatile functionality, and tunable architecture. Conventional solution-based methods of producing COFs are marred by slow reactions that produce powders that are difficult to process into adaptable form factors for functional applications, and there is a need for facile and fast synthesis techniques for making crystalline and ordered covalent organic framework (COF) thin films. In this work, we report a chemical vapor deposition (CVD) approach utilizing co-evaporation of two monomers onto a heated substrate to produce highly crystalline, defect-free COF films and coatings with hydrazone, imine, and ketoenamine COF linkages. Further, this all-in-one synthesis technique produces highly crystalline, 40 nm–1 μm-thick COF films on Si/SiO2 substrates in less than 30 min. Crystallinity and alignment were proven by using a combination of grazing-incidence wide-angle X-ray scattering (GIWAXS) and transmission electron microscopy (TEM), and successful conversion of the monomers to produce the target COF was supported by Raman spectroscopy, X-ray photoelectron spectroscopy (XPS), and UV–vis measurements. Additionally, we used atomic force microscopy (AFM) to investigate the growth mechanisms of these films, showing the coalescence of triangular crystallites into a smooth film. To show the wide applicability and scope of the CVD process, we also prepared crystalline ordered COF films with imine and ketoenamine linkages. These films show potential as high-quality size exclusion membranes, catalytic platforms, and organic transistors.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗