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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 91 records · Page 5
All sourcesNASA NTRSDOE OSTI
DOE OSTI2026

Bioinorganic Chemistry of Nitrification: Structure and Function of Ammonia Monooxygenase (Final Technical Report)

The overarching goal of this project was to elucidate biochemical mechanisms that ubiquitous microorganisms use to enable primary metabolism based on nitrification, the multi-electron oxidation of ammonia (NH 3 ) to nitrite (NO 2 – ). This chemistry enables life to substitute carbon based fuel with nitrogen. Understanding the underlying chemistry was pursued to help inform the use of ammonia as an alternative fuel source compared to petroleum, capitalizing on the widespread infrastructure for production and distribution of this substance in the US. This project specifically focused on characterizing ammonia monooxygenase, an integral membrane copper protein that initiates nitrification via the aerobic oxidation of NH 3 to hydroxylamine (NH 2 OH).

09 BIOMASS FUELS↗
DOE OSTI2026

In Vitro Selection of Antibodies Targeting Yersinia pestis Membrane Lipids Using Nanodisc-Based Antigen Presentation

Proteins are the most common targets for antibody discovery and vaccine development, but their sequence variability can limit the breadth of resulting antigens. Lipids represent an alternative class of antigens due to their structural conservation and roles in host–pathogen interactions. Here, we describe the development and optimization of an in vitro antibody selection workflow using lipid-containing nanodiscs as antigen presentation platforms to enable phage and yeast display selections under conditions adapted for these non-protein targets. Lipopolysaccharide (LPS) nanodiscs were first used as a model system to evaluate selection strategies, including competitive and subtractive approaches to reduce non-specific binders, yielding peptide and single-chain variable fragment (scFv) binders that were affinity matured to improve binding signals. The same approach was subsequently used to select scFv antibodies that recognize lipid nanodiscs prepared from Yersinia pestis membrane lipid extracts. These antibodies show binding to lipid nanodiscs derived from Y. pestis, with evidence of selectivity relative to control nanodiscs. Overall, this work establishes a workflow for antibody selection against lipid-containing nanodisc antigens and highlights practical considerations associated with these targets. The approach may be useful for generating affinity reagents to membrane-associated lipids, although further characterization is required to define antigen specificity and functional activity.

59 BASIC BIOLOGICAL SCIENCES↗
DOE OSTI2024

Hydrogen Production, Grid Integration, and Scaling for the Future

The project will explore near and long-term visions towards the commercialization of grid integrated electrolysis systems to inform deployment across the planning, procurement, and operation stages of hydrogen production on the grid. It will leverage NREL's state-of-the-art 1.25 MW polymer electrolyte membrane (PEM) electrolyzer system to characterize system performance in relevant scenarios, also creating a digital twin for emulation in the Advanced Research on Integrated Energy Systems (ARIES) virtual environment and performing hardware-in-the-loop (HIL) testing of pilot scale, decentralized, and centralized hydrogen systems.

electrolysis systems↗
NASA NTRS2002

Parallel characterization of anaerobic toluene- and ethylbenzene-degrading microbial consortia by PCR-denaturing gradient gel electrophoresis, RNA-DNA membrane hybridization, and DNA microarray technology

A mesophilic toluene-degrading consortium (TDC) and an ethylbenzene-degrading consortium (EDC) were established under sulfate-reducing conditions. These consortia were first characterized by denaturing gradient gel electrophoresis (DGGE) fingerprinting of PCR-amplified 16S rRNA gene fragments, followed by sequencing. The sequences of the major bands (T-1 and E-2) belonging to TDC and EDC, respectively, were affiliated with the family Desulfobacteriaceae. Another major band from EDC (E-1) was related to an uncultured non-sulfate-reducing soil bacterium. Oligonucleotide probes specific for the 16S rRNAs of target organisms corresponding to T-1, E-1, and E-2 were designed, and hybridization conditions were optimized for two analytical formats, membrane and DNA microarray hybridization. Both formats were used to characterize the TDC and EDC, and the results of both were consistent with DGGE analysis. In order to assess the utility of the microarray format for analysis of environmental samples, oil-contaminated sediments from the coast of Kuwait were analyzed. The DNA microarray successfully detected bacterial nucleic acids from these samples, but probes targeting specific groups of sulfate-reducing bacteria did not give positive signals. The results of this study demonstrate the limitations and the potential utility of DNA microarrays for microbial community analysis.

Non-NASA Center↗
NASA NTRS1972

Study of permeability characteristics of membranes

A method is reported for evaluating transport experiments with membranes which is based on conservative fluxes, i.e. fluxes of quantities which do not vary across the membrane in the steady state. Conductance coefficients were calculated for the system: 0.05 N NaCl - C-103 cation-exchange membrane- 0.1 N NaCl. It is concluded that this method can be used to characterize any system of the type - solution-membrane-solution.

Spiegler, K. S.↗
NASA NTRSDate not supplied

Advances in Low-Cost Manufacturing and Folding of Solar Sail Membrane

Solar sail membranes must have a high area-to-mass ratio and high solid volume fraction when stowed. In order to meet mission requirements, current solar sail projects, such as the NASA Near Earth Asteroid Scout and Advanced Composite Solar Sail System, require metallized sail membranes with thicknesses on the order of 2-3 μm. These very thin membranes do not retain creases like thicker membranes, solar panels, or paper models. For CubeSat-class spacecraft, volume, rather than mass, is often the driving requirement for deployable structural elements. These two factors make it both difficult and highly desirable to characterize the practical differences between various membrane designs and packaging methods with laboratory demonstrations. This paper presents lessons gathered from lab work on solar sail membranes at a 9-meter scale. Among other results, laboratory deployment of a full-scale sail quadrant revealed important differences between seaming methods.

Olive R Stohlman↗
NASA NTRS1994

Characterization of the association of nitrate reductase with barley (Hordeum vulgare L.) root membranes

The nature of the association between nitrate reductase (NR) and membranes was examined. Nitrate reductase activity (NRA) associated with the microsomal fraction of barley (Hordeum vulgare L.) roots amounted to 0.6 to 0.8% of soluble NRA following sonication in the presence of 250 mM KI and repeated osmotic shock. This treatment removed all contaminating soluble NRA from microsomes of uninduced barley roots that had been homogenized in a soluble extract from roots of NO3(-)-induced plants. On continuous sucrose gradients, NRA co-migrated specifically with VO4(-)-sensitive ATPase activity, a plasma membrane (PM) marker; activity of glucose-6-phosphate dehydrogenase, assayed as cytosolic marker, co-migrated with NRA. Microsomal NRA was absent in barley deficient in soluble NR. Perturbation and trypsinolysis experiments with PM vesicles isolated by aqueous two-phase partitioning indicated that NR is associated with the periphery of the cytoplasmic face of the bilayer. These results demonstrate that PM and soluble NRs are essentially the same protein but that the membrane-associated form is tightly bound. Although it is possible that PM-associated NR exists in vivo, unequivocal evidence for this has yet to be shown. However, PM NR is definitely present in vitro.

Non-NASA Center↗
NASA NTRS2004

Validation of Laser-Induced Fluorescent Photogrammetric Targets on Membrane Structures

The need for static and dynamic characterization of a new generation of inflatable space structures requires the advancement of classical metrology techniques. A new photogrammetric-based method for non-contact ranging and surface profiling has been developed at NASA Langley Research Center (LaRC) to support modal analyses and structural validation of this class of space structures. This full field measurement method, known as Laser-Induced Fluorescence (LIF) photogrammetry, has previously yielded promising experimental results. However, data indicating the achievable measurement precision had not been published. This paper provides experimental results that indicate the LIF-photogrammetry measurement precision for three different target types used on a reflective membrane structure. The target types were: (1) non-contact targets generated using LIF, (2) surface attached retro-reflective targets, and (3) surface attached diffuse targets. Results from both static and dynamic investigations are included.

Jones, Thomas W.↗
DOE OSTI2025

CpoS-Inc interactions facilitate host cell modulation during Chlamydia trachomatis infection

ABSTRACT Chlamydia trachomatis ( C.t .), the leading bacterial cause of sexually transmitted infections, replicates within a unique intracellular compartment called the inclusion, which is modified by secreted proteins known as inclusion membrane (Inc) proteins. Here, we further characterize CpoS, an Inc protein previously shown to be critical for bacterial replication and inclusion development. We demonstrate that CpoS directly binds multiple coiled-coil region-containing Incs and engages Rab GTPases at a separate site. Notably, CpoS-InaC interactions facilitate the recruitment of select Arf GTPases to the inclusion membrane, while Rab recruitment occurs independently of these interactions. Biochemical and biophysical analyses revealed that Incs self-oligomerize to form higher-ordered structures, with CpoS adopting a tetrameric conformation resembling that of eukaryotic SNARE proteins. We propose that these assemblies serve as scaffolds to orchestrate vesicle docking, tethering, and fusion. Our findings highlight the intricate interplay between bacterial and host factors, revealing how C.t . leverages both Inc-Inc interactions and host protein engagement to manipulate vesicular trafficking and sustain infection.

Tijerina, Xavier [Department of Microbiology and I↗
NASA NTRS2006

Analysis of Membrane Lipids of Airborne Micro-Organisms

A method of characterization of airborne micro-organisms in a given location involves (1) large-volume filtration of air onto glass-fiber filters; (2) accelerated extraction of membrane lipids of the collected micro-organisms by use of pressurized hot liquid; and (3) identification and quantitation of the lipids by use of gas chromatography and mass spectrometry. This method is suitable for use in both outdoor and indoor environments; for example, it can be used to measure airborne microbial contamination in buildings ("sick-building syndrome"). The classical approach to analysis of airborne micro-organisms is based on the growth of cultureable micro-organisms and does not provide an account of viable but noncultureable micro-organisms, which typically amount to more than 90 percent of the micro-organisms present. In contrast, the present method provides an account of all micro-organisms, including cultureable, noncultureable, aerobic, and anaerobic ones. The analysis of lipids according to this method makes it possible to estimate the number of viable airborne micro-organisms present in the sampled air and to obtain a quantitative profile of the general types of micro-organisms present along with some information about their physiological statuses.

MacNaughton, Sarah↗
NASA NTRS1996

Transport proteins of the plant plasma membrane

Recently developed molecular and genetic approaches have enabled the identification and functional characterization of novel genes encoding ion channels, ion carriers, and water channels of the plant plasma membrane.

Non-NASA Center↗
NASA NTRS2019

Advances in Low-Cost Manufacturing and Folding of Solar Sail Membranes

Solar sail membranes must have a high area-to-mass ratio and high solid volume fraction when stowed. In order to meet mission requirements, current solar sail projects, such as NASA’s Near Earth Asteroid Scout, require metallized sail membranes with thicknesses on the order of 2-3 μm. These very thin membranes do not retain creases like thicker membranes, solar panels, or paper models. For Cubesat-class spacecraft, volume, rather than mass, is often the driving requirement for deployable structural elements. These two factors make it both difficult and highly desirable to characterize the practical differences between solar sail membrane packaging methods with laboratory demonstrations. This paper presents lessons gathered from lab work with solar sail membranes at a 10-meter scale.

Stohlman, Olive R.↗
NASA NTRS2011

Mobility Spectrometer Studies on Hydrazine and Ammonia Detection

An airborne vapor analyzer for detecting sub- to low- parts-per-million (ppm) hydrazine in the presence of higher concentration levels of ammonia has been under development for the Orion program. The detector is based on ambient pressure ionization and ion mobility characterization. The detector encompasses: 1) a membrane inlet to exclude particulate and aerosols from the analyzer inlet; 2) a method to separate hydrazine from ammonia which would otherwise lead to loss of calibration and quantitative accuracy for the hydrazine determination; and 3) response and quantitative determinations for both hydrazine and ammonia. Laboratory studies were made to explore some of these features including mobility measurements mindful of power, size, and weight issues. The study recommended the use of a mobility spectrometer of traditional design with a reagent gas and equipped with an inlet transfer line of bonded phase fused silica tube. The inlet transfer line provided gas phase separation of neutrals of ammonia from hydrazine at 50 C simplifying significantly the ionization chemistry that underlies response in a mobility spectrometer. Performance of the analyzer was acceptable between ranges of 30 to 80 C for both the pre-fractionation column and the drift tube. An inlet comprised of a combined membrane with valve-less injector allowed high speed quantitative determination of ammonia and hydrazine without cross reactivity from common metabolites such as alcohols, esters, and aldehydes. Preliminary test results and some of the design features are discussed.

Niu, William↗
DOE OSTI2025

Revealing the Crystalline Architecture of Semicrystalline Ion Exchange Membranes for the Design of Conductive and Durable Alkaline Anion Exchange Membranes

Alkaline anion exchange membrane (AAEM) fuel cells offer a cost-effective alternative to proton exchange membrane (PEM) fuel cells by eliminating the need for expensive precious metal catalysts. In both PEMs and AAEMs, semicrystalline polymers are a common choice, as the crystalline domains can act as mechanical reinforcements that limit swelling and promote mechanical durability in the material. However, spatially resolved characterization of crystalline organization in ion exchange membranes beyond ensemble-averaged X-ray scattering is underrepresented, likely in part due to ionization damage limitations in soft materials. Here, in this study, we resolve the nanometer-size crystallites in semicrystalline ion exchange membranes by applying cryogenic four-dimensional scanning transmission electron microscopy (cryo-4D-STEM) along with data-processing algorithms designed to optimize signals at a low dose to minimize radiation damage. We investigate the effects of synthesis components, including molecular weight and thermal treatment, on a model system of AAEMs in comparison to Nafion, the most commonly used and commercially successful PEM today. We find that excess water uptake in polymer membranes, a property directly associated with weak mechanical durability and with possible negative impacts on ion conductivity, can be reduced by over 30% by varying the polymer's crystalline morphology through changes in synthesis parameters such as molecular weight and thermal history. Our results indicate that this improvement is correlated with smaller crystalline domains with a more homogeneous distribution. More broadly, these results demonstrate how the crystalline architecture of polymer membranes can be tuned through their chemistry and thermal treatment in order to improve their conductivity and durability for commercial fuel cell performance.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
NASA NTRS2003

Hydrogen Purification Using Natural Zeolite Membranes

The School of Science at Universidad del Turabo (UT) have a long-lasting investigation plan to study the hydrogen cleaning and purification technologies. We proposed a research project for the synthesis, phase analysis and porosity characterization of zeolite based ceramic perm-selective membranes for hydrogen cleaning to support NASA's commitment to achieving a broad-based research capability focusing on aerospace-related issues. The present study will focus on technology transfer by utilizing inorganic membranes for production of ultra-clean hydrogen for application in combustion. We tested three different natural zeolite membranes (different particle size at different temperatures and time of exposure). Our results show that the membranes exposured at 900 C for 1Hr has the most higher permeation capacity, indicated that our zeolite membranes has the capacity to permeate hydrogen.

DelValle, William↗
NASA NTRS2001

Corner Wrinkling at a Square Membrane Due to Symmetric Mechanical Loads

Thin-film membrane structures are under consideration for use in many future gossamer spacecraft systems. Examples include sunshields for large aperture telescopes, solar sails, and membrane optics. The development of capabilities for testing and analyzing pre-tensioned, thin film membrane structures is an important and challenging aspect of gossamer spacecraft technology development. This paper presents results from experimental and computational studies performed to characterize the wrinkling behavior of thin-fi[m membranes under mechanical loading. The test article is a 500 mm square membrane subjected to symmetric comer loads. Data is presented for loads ranging from 0.49 N to 4.91 N. The experimental results show that as the load increases the number of wrinkles increases, while the wrinkle amplitude decreases. The computational model uses a finite element implementation of Stein-Hedgepeth membrane wrinkling theory to predict the behavior of the membrane. Comparisons were made with experimental results for the wrinkle angle and wrinkled region. There was reasonably good agreement between the measured wrinkle angle and the predicted directions of the major principle stresses. The shape of the wrinkle region predicted by the finite element model matches that observed in the experiments; however, the size of the predicted region is smaller than that determined in the experiments.

Blandino, Joseph R.↗