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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 1,045 records · Page 58
All sourcesNASA NTRSDOE OSTI
NASA NTRS1992

The evolution of energy-transducing systems. Studies with an extremely halophilic archaebacterium

The F-type ATPases are found in remarkably similar versions in the energy-transducing membranes of eubacteria, chloroplasts, and mitochondria. Thus, it is likely that they have originated early in the evolution of life, which is consistent with their function as key enzymes of cellular metabolism. The archaebacteria are a group of microorganisms which, as shown by molecular sequencing and biochemical data, have diverged early from the main line of prokaryotic evolution. From studies of members of all three major groups of archaebacteria - the halophiles, methanogens, and thermoacidophiles - it emerged that they possess a membrane ATPase which differs from the F-ATPases. The goal of this project was a comparison of the ATPase from the halophilic archaebacterium Halobacterium saccharovorum with the well-characterized F-type ATPases on the molecular level. Amino acid sequences of critical regions of the enzyme were to be determined, as well as immunoreactions of single subunits in the search for common epitopes. The results were expected to allow a decision about the nature of archaebacterial ATPases, their classification as one of the known or, alternatively, novel enzyme complexes, and possibly deduction of events during the early evolution of energy-transducing systems.

Stan-Lotter, Helga↗
NASA NTRS2010

Self-Deployable Membrane Structures

Currently existing approaches for deployment of large, ultra-lightweight gossamer structures in space rely typically upon electromechanical mechanisms and mechanically expandable or inflatable booms for deployment and to maintain them in a fully deployed, operational configuration. These support structures, with the associated deployment mechanisms, launch restraints, inflation systems, and controls, can comprise more than 90 percent of the total mass budget. In addition, they significantly increase the stowage volume, cost, and complexity. A CHEM (cold hibernated elastic memory) membrane structure without any deployable mechanism and support booms/structure is deployed by using shape memory and elastic recovery. The use of CHEM micro-foams reinforced with carbon nanotubes is considered for thin-membrane structure applications. In this advanced structural concept, the CHEM membrane structure is warmed up to allow packaging and stowing prior to launch, and then cooled to induce hibernation of the internal restoring forces. In space, the membrane remembers its original shape and size when warmed up. After the internal restoring forces deploy the structure, it is then cooled to achieve rigidization. For this type of structure, the solar radiation could be utilized as the heat energy used for deployment and space ambient temperature for rigidization. The overall simplicity of the CHEM self-deployable membrane is one of its greatest assets. In present approaches to space-deployable structures, the stow age and deployment are difficult and challenging, and introduce a significant risk, heavy mass, and high cost. Simple procedures provided by CHEM membrane greatly simplify the overall end-to-end process for designing, fabricating, deploying, and rigidizing large structures. The CHEM membrane avoids the complexities associated with other methods for deploying and rigidizing structures by eliminating deployable booms, deployment mechanisms, and inflation and control systems that can use up the majority of the mass budget

Sokolowski, Witold M.↗
DOE OSTI2026

NiFeCo-based catalysts in high current zero-gap anion exchange membrane water electrolyzers

Understanding degradation mechanisms in pure water anion exchange membrane water electrolyzers is essential for developing durable and precious metal-free hydrogen production systems, yet electronic, chemical, and transport-driven pathways often occur simultaneously at the anode. To separate these effects, we establish a morphology invariant Ni/Fe/Co thin film model catalyst platform using physical vapor deposition and systematically compare composition-dependent behavior under both pure water and 0.1 M KOH feeds. Devices were operated under industrially relevant current density conditions, galvanostatically at 1 A cm −2 for 24 hours; metal dissolution, ionomer oxidation, and resistance growth were quantified using inductively coupled plasma mass spectrometry, X-ray photoelectron spectroscopy (XPS), and electrochemical impedance spectroscopy. Under pure-water operation, Ni-rich films showed voltage increases that correlated with rising total cell resistance (ΔV ≈ 243 mV, ΔR ≈ 0.17 Ω cm 2 ). Co-rich films maintained near constant voltages with minimal resistance change (ΔV < 10 mV, ΔR ≈ 0.03 Ω cm 2 ) but induced pronounced ionomer oxidation observed by XPS. In 0.1 M KOH, ionomer oxidation is suppressed, and impedance growth is minimized (<0.08 Ω cm 2 ) across all compositions, consistent with reduced transport limitations and improved ionic conduction relative to pure-water feeds. These results demonstrate how a controlled thin film model platform can isolate composition electrolyte relationships and provide mechanistic design principles for stable pure water anion exchange membrane electrolyzers.

Milenia Rojas Mendoza, B. [Stanford Univ., CA (Uni↗
DOE OSTI2025

Shape‐Evolving Structured Liquids

Migration, division, and reconfiguration - functions essential to living systems - are driven by active processes. Developing synthetic mimics is an outstanding challenge. Lipid bilayers that bound natural systems are locally deformed by active species, e.g., microtubules, but the resulting non-equilibrium shapes relax when active species motion ceases, and the shape changes lack immediate control. A fully synthetic system is described, driven by active particles encapsulated by a reconfigurable nanoparticle-surfactant membrane that undergoes shape fluctuations reminiscent of living cells. These shape changes are preserved after particle activity stops. Surfactant concentration tunes the interfacial tension over three orders of magnitude, making on-demand shape evolution possible. Directional migration, division, and reconfiguration across multiple scales are possible, leading to a new class of biomimetic, reconfigurable, and responsive materials, paving the way for autonomous synthetic machines.

Kim, Paul Y↗
DOE OSTI2026

High finesse buckled microcavities

Optical cavities are widely used in modern science and technology to enable a wide range of both quantum and classical applications. Recently, the growing demand for miniaturization and high performance has fueled the exploration of new fabrication methods beyond traditional polishing techniques and macroscopic mirrors. Visible and near-infrared (NIR) wavelengths are particularly important for quantum applications, where achieving low-loss resonators is also more challenging than in the telecom range, presenting unique challenges and opportunities for microscopic cavity systems. Here, we present a fabrication method for making NIR microcavities using buckled dielectric membrane mirrors, achieving a record finesse of 0.9 million at 780 nm for microcavities. We demonstrated flexible device geometries—including singular mirrors and mirror arrays, featuring radii of curvature ranging from 1 to 10 mm. The fabrication process offers high uniformity, high yield, and robust performance across a wide range of cavity lengths. Additionally, we can produce easy-to-assemble microcavity packages, with a total volume of ~2(4) mm 3 , featuring optical modes with a linewidth of 5.16 MHz (570 kHz) and a free spectral range (FSR) of 3.18 THz (150 GHz). Our results extend the frontier of microcavity fabrication for classical and quantum photonic technologies.

Ding, Sophie Weiyi [Harvard Univ., Cambridge, MA (↗
DOE OSTI2022

Crosslinked Anionic Exchange Membranes (Spring Quarter Report)

With ever growing climate concerns, studying and optimizing hydrogen gas electrolyzers and fuel cells are of high importance. Polymeric anionic exchange membranes (AEM) are attractive replacements to the industry standard proton exchange membranes (PEM) due to their lack of precious metal catalysts and acidic conditions. However, AEMs on the market have yet to preform comparatively to PEMs. To bring AEMs to a competitive level, crosslinking chemistry within the polymer membranes is being investigated to enhance mechanical properties and performance. For this quarter, electrochemical systems, important AEM properties and considerations, and some characterization methods will be reviewed.

08 HYDROGEN↗
DOE OSTI2023

Abstract for CRADA between National Energy Technology Laboratory and United States Steel Corporation

The United States Department of Energy’s National Energy Technology Laboratory (DOE-NETL) is committed to developing practical carbon capture solutions for reducing CO2 emissions from fossil fueled industrial sources, including steel manufacturing, cement manufacturing, and others. To address this need, NETL has developed a new ultra-high permeance polymer membrane that is optimized to reduce the cost of post-combustion carbon capture. NETL will partner with the U. S. Steel to demonstrate the effectiveness of this gas separation membrane technology using waste gas from a blast furnace at a steel production plant. Systems analysis will be conducted to understand the potential benefits for full scale implementation of the technology for steel manufacturing.

36 MATERIALS SCIENCE↗
DOE OSTI2021

H 2 Production Pathways Cost Analysis (2016 - 2021) (Final Report)

This final report documents cost analysis conducted for the Department of Energy over a five year period (2016 to 2021) pertaining to hydrogen production and delivery system components, focusing on the key remaining challenges of the technology pathways within the Hydrogen Production and Delivery sub-program portfolio. A particular focus was placed on electrolysis for the generation of hydrogen. The effort primarily used the H2A discounted cash flow computational model as a tool to project hydrogen cost ($/kgH 2 ) and determine status improvements resulting from technology advancements. The effort also considered cost as a function of production volume, employed error bars to illustrate uncertainties in the cost estimates, and utilized sensitivity analyses to show the potential for cost reductions. The project examined a range of hydrogen production and delivery related systems. These included WireTough wire-wrapped pressure vessels for hydrogen storage, proton exchange membrane (PEM) electrolysis, solid oxide electrolysis (SOE), anion exchange membrane (AEM) electrolysis, photoelectrochemical (PEC) electrolysis, solar thermochemical hydrogen (STCH) production, the cost of energy transmission, and a study on the necessary price of hydrogen to produce competitively-priced electricity via fuel cell conversion.

08 HYDROGEN↗
NASA NTRS1982

ACCESS computer program for the synthesis of large structural systems

The structural-synthesis computer code ACCESS-3, originally limited to the optimization of relatively simple problems involving truss, membrane, and shear panel elements, has been restructured to make it applicable to structures with a larger number of degrees-of-freedom, design variables, and constraints. The modifications made allow the use of six degrees-of-freedom per node and permit the out-of-core solution of large matrix equations encountered at the analysis stage. Also, finite elements which permit pure bending as well as combined bending and membrane (axial) behavior have been added to satisfy the need for a more comprehensive set of elements. Like its predecessor, the new version of the program combines the approximation concepts with primal or dual formulations to provide an efficient optimization tool.

Fleury, C.↗
NASA NTRS1988

Automated Water-Purification System

Reverse-osmosis system operates and maintains itself with minimal human attention, using programmable controller. In purifier, membranes surround hollow cores through which clean product water flows out of reverse-osmosis unit. No chemical reactions or phase changes involved. Reject water, in which dissolved solids concentrated, emerges from outer membrane material on same side water entered. Flow controls maintain ratio of 50 percent product water and 50 percent reject water. Membranes expected to last from 3 to 15 years.

Ahlstrom, Harlow G.↗
NASA NTRS2003

Mathematical model of diffusion-limited evolution of multiple gas bubbles in tissue

Models of gas bubble dynamics employed in probabilistic analyses of decompression sickness incidence in man must be theoretically consistent and simple, if they are to yield useful results without requiring excessive computations. They are generally formulated in terms of ordinary differential equations that describe diffusion-limited gas exchange between a gas bubble and the extravascular tissue surrounding it. In our previous model (Ann. Biomed. Eng. 30: 232-246, 2002), we showed that with appropriate representation of sink pressures to account for gas loss or gain due to heterogeneous blood perfusion in the unstirred diffusion region around the bubble, diffusion-limited bubble growth in a tissue of finite volume can be simulated without postulating a boundary layer across which gas flux is discontinuous. However, interactions between two or more bubbles caused by competition for available gas cannot be considered in this model, because the diffusion region has a fixed volume with zero gas flux at its outer boundary. The present work extends the previous model to accommodate interactions among multiple bubbles by allowing the diffusion region volume of each bubble to vary during bubble evolution. For given decompression and tissue volume, bubble growth is sustained only if the bubble number density is below a certain maximum.

Evaluation Studies↗
NASA NTRS1997

Immunolocalization of integrin-like proteins in Arabidopsis and Chara

Integrins are a large family of integral plasma membrane proteins that link the extracellular matrix to the cytoskeleton in animal cells. As a first step in determining if integrin-like proteins are involved in gravitropic signal transduction pathways, we have used a polyclonal antibody against the chicken beta1 integrin subunit in western blot analyses and immunofluorescence microscopy to gain information on the size and location of these proteins in plants. Several different polypeptides are recognized by the anti-integrin antibody in roots and shoots of Arabidopsis and in the internodal cells and rhizoids of Chara. These cross-reactive polypeptides are associated with cellular membranes, a feature which is consistent with the known location of integrins in animal systems. In immunofluorescence studies of Arabidopsis roots, a strong signal was obtained from labeling integrin-like proteins in root cap cells, and there was little or no immunolabel in other regions of the root tip. While the antibody stained throughout Chara rhizoids, the highest density of immunolabel was at the tip. Thus, in both Arabidopsis roots and Chara rhizoids, the sites of gravity perception/transduction appear to be enriched in integrin-like molecules.

Non-NASA Center↗
NASA NTRS2001

Cell-cycle research with synchronous cultures: an evaluation

The baby-machine system, which produces new-born Escherichia coli cells from cultures immobilized on a membrane, was developed many years ago in an attempt to attain optimal synchrony with minimal disturbance of steady-state growth. In the present article, we put forward a model to describe the behaviour of cells produced by this method, and provide quantitative evaluation of the parameters involved, at each of four different growth rates. Considering the high level of selection achievable with this technique and the natural dispersion in interdivision times, we believe that the output of the baby machine is probably close to optimal in terms of both quality and persistence of synchrony. We show that considerable information on events in the cell cycle can be obtained from populations with age distributions very much broader than those achieved with the baby machine and differing only modestly from steady state. The data presented here, together with the long and fruitful history of findings employing the baby-machine technique, suggest that minimisation of stress on cells is the single most important factor for successful cell-cycle analysis.

Non-NASA Center↗
NASA NTRS2008

Hydrogen Research for Spaceport and Space-Based Applications: Fuel Cell Projects

The activities presented are a broad based approach to advancing key hydrogen related technologies in areas such as fuel cells, hydrogen production, and distributed sensors for hydrogen-leak detection, laser instrumentation for hydrogen-leak detection, and cryogenic transport and storage. Presented are the results from research projects, education and outreach activities, system and trade studies. The work will aid in advancing the state-of-the-art for several critical technologies related to the implementation of a hydrogen infrastructure. Activities conducted are relevant to a number of propulsion and power systems for terrestrial, aeronautics and aerospace applications. Fuel cell research focused on proton exchange membranes (PEM), solid oxide fuel cells (SOFC). Specific technologies included aircraft fuel cell reformers, new and improved electrodes, electrolytes, interconnect, and seals, modeling of fuel cells including CFD coupled with impedance spectroscopy. Research was conducted on new materials and designs for fuel cells, along with using embedded sensors with power management electronics to improve the power density delivered by fuel cells. Fuel cell applications considered were in-space operations, aviation, and ground-based fuel cells such as; powering auxiliary power units (APUs) in aircraft; high power density, long duration power supplies for interplanetary missions (space science probes and planetary rovers); regenerative capabilities for high altitude aircraft; and power supplies for reusable launch vehicles.

Anderson, Tim↗
DOE OSTI2022

Methods for carbon dioxide hydrogenation

A method of carbon dioxide hydrogenation comprises introducing gaseous water to a positive electrode of an electrolysis cell comprising the positive electrode, a negative electrode, and a proton-conducting membrane between the positive electrode and the negative electrode. The proton-conducting membrane comprises an electrolyte material having an ionic conductivity greater than or equal to about 10-2 S/cm at one or more temperatures within a range of from about 150° C. to about 650° C. Carbon dioxide is introduced to the negative electrode of the electrolysis cell. A potential difference is applied between the positive electrode and the negative electrode of the electrolysis cell to generate hydrogen ions from the gaseous water that diffuses through the proton-conducting membrane and hydrogenates the carbon dioxide at the negative electrode. A carbon dioxide hydrogenation system is also described.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2023

Fuel cell and electrolyzer hotbox module using conductive zirconia stacks

Modular pressurized hotbox for use and substitution in a variety of pressurized electrochemical applications to include reversible solid oxide electrolyzer and fuel cells, energy storage systems, renewable fuel production, solid-state hydrogen pumping and liquefaction, and oxygen transport membranes. This is enabled by mixed electronic and ionic conducting compositions of vanadia-yttria and vanadia-calcia stabilized zirconia and a dry powder method of manufacture for ceramic core stacks.

McLarty, Dustin↗
DOE OSTI2024

Building a Prospective LCA Framework to Analyze Emerging Technologies in a Dynamic System Context

NREL's Lifecycle Analysis Integration into Opensource Numerical models (LiAISON) framework computes temporally explicit life cycle impacts and resource uses for specific technologies (foreground) in a dynamic system context (background). LiAISON computes results for a series of environmental mid-points enabling an analysis of prospective tradeoffs of emerging technologies toward 2100. This prospective feature is of critical importance when analyzing present-day emerging technologies whose large-scale impacts during deployment phases will occur in different, future system contexts. LiAISON systematically accounts for dynamic system changes by applying an integrated background of the future energy-economy-land-climate system, generated by exogenous integrated assessment models (IAMs). Using IAM scenarios, LiAISON generates a time-series of life cycle inventory (LCI) databases, which are then used to calculate the impacts per functional unit per time step. This expands current practice of using static, future system assumptions, e.g., a specific grid-mix each year. Further, IAM scenarios are provided in a standardized format of shared-socioeconomic pathways (SSP) and representative concentration pathways (RCP) combinations. These are coherent, regularly, published, and peer-reviewed scenario combinations that establish a reproducible and standardized societal and climate mitigation futures context. They are comparable across IAMs and expand the system boundary of the traditional LCA by including dimensions such as societal and behavioral changes. We apply the framework to assess two emerging Power-to-Hydrogen processes, high temperature electrolysis using solid oxide fuel cell (HT-SOE) and polymer electrolyte membrane electrolysis (PEME). We compare the technologies to a baseline Hydrogen production process via steam methane reforming. Despite the decarbonized electricity systems' beneficial effects on the PtH2 processes' carbon intensities, we find environmental tradeoffs, which require technology improvements via learning-by-doing to be alleviated. Future work via ongoing collaborations will focus on linking the framework to other energy-economy-land-climate models and open-source life cycle inventory databases.

ENERGY PLANNING, POLICY, AND ECONOMY↗