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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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All sourcesNASA NTRSDOE OSTI
NASA NTRS2012

Processing NASA Earth Science Data on Nebula Cloud

Three applications were successfully migrated to Nebula, including S4PM, AIRS L1/L2 algorithms, and Giovanni MAPSS. Nebula has some advantages compared with local machines (e.g. performance, cost, scalability, bundling, etc.). Nebula still faces some challenges (e.g. stability, object storage, networking, etc.). Migrating applications to Nebula is feasible but time consuming. Lessons learned from our Nebula experience will benefit future Cloud Computing efforts at GES DISC.

Chen, Aijun↗
NASA NTRS2013

Heat Melt Compaction as an Effective Treatment for Eliminating Microorganisms from Solid Waste

One of the technologies being tested at NASA Ames Research Center (ARC) for the Advance Exploration Systems program and as part of the logistics and repurposing project is heat melt compaction (HMC) of solid waste. Reduces volume, removes water and renders a biologically stable and safe product. The HMC compacts and reduces the trash volume as much as 90o/o greater than the current manual compaction used by the crew.The project has three primary goals or tasks. 1. Microbiological analysis of HMC hardware surfaces before and after operation. 2. Microbiological and physical characterizations of heat melt tiles made from trash at different processing times and temperatures. 3. Long term storage and stability of HMC trash tiles or "Do the bugs grow back?"

Hummerick, Mary P.↗
NASA NTRS1980

Life and stability testing of packaged low-cost energy storage materials

Thermal cycling and performance tests, performed to verify the package integrity, life, and stability of the chub packaged materials system for storage coolness with application to residential air conditioning, are described. The moisture vapor retention characteristics of the laminate film for long term chub performance was determined. The stability, mechanical integrity, and thermal performance of chubs following mechanical shock, vibration, and temperature extremes is reported.

Frysinger, G. R.↗
NASA NTRSDate not supplied

Nutrient Stability in NASA Spaceflight Experiment Rodent Food Bars

Nutrient-upgraded Rodent Food Bars are the standard diet for mice involved in spaceflight experiments aboard the International Space Station as part of NASA’s Rodent Research Project. These Food Bars are a twin-screw extruded AIN-93G based product with nutrient additives to preserve a healthy and complete diet for the animals, and the bar form factor is necessary for use in the microgravity environment. Due to the nature of NASA flight projects and the lengthy production process of these Food Bars, a shelf-life assessment was undertaken to determine nutrient stability over an extended storage time. To assess palatability and stability over an extended duration, a panel of lipid oxidation markers and both fat- and water-soluble vitamins were assessed under various time and temperature conditions via AOAC International standardized methodology. Thiamine was the least stable vitamin at room temperature. Bars that had been continually kept at 4C (t=6, 12, 27 months) showed significantly higher levels of thiamine (via Student’s t-test) compared to all other bars that underwent some degree of ambient temperature storage. This suggests that refrigeration is a key component in maintaining adequate nutrient levels in these relatively high moisture (average 29.3%) food bars. Also of note was the level of Vitamin A in the form of retinol. There was no correlation to storage temperature, but rather the only factor having an effect on retinol levels was time. As low, yet consistent decrease in retinol was observed over the course of the experiment, though at no time did the retinol levels drop below the rodent Nutrient Requirements for Laboratory Animals (NRC). In conclusion, over the 27-month time course, all analyzed vitamins and lipid oxidation factors remained relatively stable and at levels which provide fully sufficient nutrition to rodents during spaceflight. Some groups however, displayed higher-than-expected aerobic and anaerobic bacteria colony forming units, which is believed to stem from a since-revised handling technique.

Food↗
NASA NTRS1978

Requisite temperatures for the stabilization of atomic H in solid H2

If an atomic hydrogen/molecular hydrogen propellant containing at least 15% free H atoms by weight may be used, values for the theoretical specific impulse near and above 750 s may be predicted. The tritium-impregnation concept has been applied to manufacturing such an H/H2 propellant, and a phenomenological rate process theory has been derived for the matrix-isolation storage and equilibrium stability of atomic H produced at such ultralow temperatures in tritium-impregnated H2. It is suggested that an energy storage efficiency greater than 0.30 may be obtained at temperatures below 100 mK. So that the storage of atomic H is stable with respect to arbitrary small perturbations, the surface temperature must be less than a critical value dependent on sample volume, tritium weight fraction, and energy storage efficiency. A derivation of the formula for this critical surface temperature is presented, noting that the energy storage efficiency is to be fixed by experiment.

Rosen, G.↗
NASA NTRS1990

State of the art and future directions for the atomic hydrogen maser

The present status of technology development for atomic hydrogen masers (H-masers) is reviewed. The limitations to frequency stability and accuracy are discussed with emphasis on the problems associated with cavity resonator instability and the lack of reproducibility and stability of the storage volume wall coating frequency shift. New types of coating developed in the Soviet Union and better, cavity resonator materials, are expected to make possible frequency at the 10(exp -16) level at 10(exp 4) sec. Better control of systematic effects should extend the long-term stability to levels better than 10(exp -15) for intervals beyond one day. Present use of H-masers as flywheel oscillators in timekeeping systems is discussed as is the outlook for the future cryogenic and room temperature H-masers as flywheel oscillators to operate very high resolution frequency discriminators based on the newly evolving technology of trapped and cooled ions and atoms.

Vessot, Robert F. C.↗
NASA NTRS1984

Optical residue addition and storage units using a Hughes liquid crystal light valve

Optical addition and storage units are described in this paper. These units are implemented using the Hughes Liquid Crystal Light Valve (LCLV) as a spatial light modulator using residue arithmetic for a numerical representation. The main hardware components of the design, besides the light valve, include an array of single-mode optical fibers that provide input information, a polarizing prism in combination with quarter-wave and half-wave retarders for residue arithmetic implementation in the adder, and a holographic array for spatial stability in the storage unit.

Habiby, S. F.↗
NASA NTRS2003

Development of Highly-Conductive Polyelectrolytes for Lithium Batteries

Future NASA and Air Force missions require reliable and safe sources of energy with high specific energy and energy density that can provide thousands of charge-discharge cycles at more than 40% depth- of-discharge and that can operate at low temperatures. All solid-state batteries have substantial advantages with respect to stability, energy density, storage fife and cyclability. Among all solid-state batteries, those with flexible polymer electrolytes offer substantial advantages in cell dimensionality and commensurability, low temperature operation and thin film design. The above considerations suggest that lithium-polymer electrolyte systems are promising for high energy density batteries and should be the systems of choice for NASA and US Air Force applications. Polyelectrolytes (single ion conductors) are among most promising avenues for achieving a major breakthrough 'in the applicability of polymer- based electrolyte systems. Their major advantages include unit transference number for the cation, reduced cell polarization, minimal salt precipitation, and favorable electrolyte stability at interfaces. Our research is focused on synthesis, modeling and cell testing of single ion carriers, polyelectrolytes. During the first year of this project we attempted the synthesis of two polyelectrolytes. The synthesis of the first one, the poly(ethyleneoxide methoxy acrylateco-lithium 1,1,2-trifluorobutanesulfonate acrylate, was attempted few times and it was unsuccessful. We followed the synthetic route described by Cowie and Spence. The yield was extremely low and the final product could not be separated from the impurities. The synthesis of this polyelectrolyte is not described in this report. The second polyelectrolyte, comb polysiloxane polyelectrolyte containing oligoether and perfluoroether sidechains, was synthesized in sufficient quantity to study the range of properties such as thermal stability, Li- ion- conductivity and stability toward lithium metal. Also, the batteries containing this polyelectrolyte were assembled and tested. The results are detailed below. The synthesis of another polyelectrolyte similar to polysiloxane polyelectrolyte has been started, however, the synthesis was not completed due to termination of the project.

Shriver, D. F.↗
NASA NTRS1988

Applications of concurrent neuromorphic algorithms for autonomous robots

This article provides an overview of studies at the Oak Ridge National Laboratory (ORNL) of neural networks running on parallel machines applied to the problems of autonomous robotics. The first section provides the motivation for our work in autonomous robotics and introduces the computational hardware in use. Section 2 presents two theorems concerning the storage capacity and stability of neural networks. Section 3 presents a novel load-balancing algorithm implemented with a neural network. Section 4 introduces the robotics test bed now in place. Section 5 concerns navigation issues in the test-bed system. Finally, Section 6 presents a frequency-coded network model and shows how Darwinian techniques are applied to issues of parameter optimization and on-line design.

Barhen, J.↗
NASA NTRS2012

Improved Whole-Blood-Staining Device

Dramatic improvements have been made in NASA s Whole Blood Staining Device (WBSD) since it was last described in "Whole-Blood-Staining Device," NASA Tech Briefs, Vol. 23, No. 10 (October 1999), page 64. The new system has a longer shelf life, a simpler and more effective operational procedure, improved interface with instrumentation, and shorter processing time. More specifically, the improvements have targeted bag and locking clip materials, sampling ports, and air pocket prevention. The WBSD stains whole blood collected during spaceflight for subsequent flow cytometric analysis. In short, the main device stains white blood cells by use of monoclonal antibodies conjugated to various fluorochromes, followed by lysing and fixing of the cells by use of a commercial reagent that has been diluted according to NASA safety standards. This system is compact, robust, and does not require electric power, precise mixing, or precise incubation times. Figure 1 depicts the present improved version for staining applications, which is a poly(tetrafluoroethylene) bag with a Luer-lock port and plastic locking clips. An InterLink (or equivalent) intravenous- injection port screws into the Luer-lock port. The inflatable/collapsible nature of the bag facilitates loading and helps to minimize the amount of air trapped in the fully loaded bag. Some additional uses have been identified for the device beyond whole blood staining. The WBSD has been configured for functional assays that require culture of live cells by housing sterile culture media, mitogens, and fixatives prior to use [Figure 2(a)]. Simple injection of whole blood allows cell-stimulation culture to be performed in reduced gravity conditions, and product stabilization prior to storage, while protecting astronauts from liquid biohazardous materials. Also, the improved WBSD has reconstituted powdered injectable antibiotics by mixing them with diluent liquids [Figure 2(b)]. Although such mixing can readily be performed on Earth by shaking in glass vials, it cannot readily be performed this way in outer space without entraining air bubbles. The present device can be preloaded with the powder and diluent(s) in separate compartments. The powder and diluent( s) can be mixed, without introducing air bubbles, by removing the clip(s), then shaking. This use of the device could also be advantageous in terrestrial applications because it maintains the isolation of the constituents until the time of use.

Sams, Clarence F.↗
NASA NTRS2015

Challenges Encountered Using Ophthalmic Anesthetics in Space Medicine

On orbit, ophthalmic anesthetics are used for tonometry and off-nominal corneal examinations. Proparacaine has been flown traditionally. However, the manufacturers recently changed its storage requirements from room temperature storage to refrigerated storage to preserve stability and prolong the shelf-life. Since refrigeration on orbit is not readily available and there were stability concerns about flying proparacaine unrefrigerated, tetracaine was selected as an alternative ophthalmic anesthetic in 2013. We will discuss the challenges encountered flying and using these anesthetics on the International Space Station.

Bayuse, T.↗
NASA NTRSDate not supplied

Microscopy Methods for Life Detection on Ocean Worlds

On Earth, light microscopy is commonly used in microbiology to identify organisms and observe their interactions with the environment; this makes it an attractive technique for in situ life detection methods on ocean worlds. As a standalone technique, brightfield microscopy, while able to provide important contextual information, has limited usefulness as a life detection technique because it is often challenging to differentiate between abiotic and biotic particles based solely on their size and shape, which may introduce risks of false positive or false negative interpretations. However, these risks can be reduced by combining brightfield microscopy with fluorescence microscopy to provide a method that correlate sample chemistry with sample morphology. In this work, we have used the Luminescence Imager for Exploration (LIfE), a brightfield and epifluorescence microscope with an integrated sample processing system (matured under the Concepts for Ocean worlds Life Detection Technology and Instrument Concepts of Europa Exploration programs) to develop methods that increase the fidelity of in situ microscopy life detection measurements through two main approaches. First, native fluorescence is excited in molecules that contain aromatic moieties such as proteins (using deep UV excitation), and energy carrying molecules and endogenous chromophores (using visible-light excitation), to correlate the location of these species with cell-like structural features (brightfield imaging). Second, fluorescent stains are used to selectively image cells and cell fragments by targeting proteins, lipids, and nucleic acids. We discuss the results of tests, obtained using ocean world analog samples, that have examined trades associated with implementing these methods autonomously in planetary missions, including the intrinsic properties of candidate fluorescence dyes and long-term storage and radiation stability.

Pavel E. Z. Klier↗
NASA NTRSDate not supplied

Microscopy Methods for Life Detection on Ocean Worlds

On Earth, light microscopy is commonly used in microbiology to identify organisms and observe their interactions with the environment; this makes it an attractive technique for in situ life detection methods on ocean worlds. As a standalone technique, brightfield microscopy, while able to provide important contextual information, has limited usefulness as a life detection technique because it is often challenging to differentiate between abiotic and biotic particles based solely on their size and shape, which may introduce risks of false positive or false negative interpretations. However, these risks can be reduced by combining brightfield microscopy with fluorescence microscopy to provide a method that correlate sample chemistry with sample morphology. In this work, we have used the Luminescence Imager for Exploration (LIfE), a brightfield and epifluorescence microscope with an integrated sample processing system (matured under the Concepts for Ocean worlds Life Detection Technology and Instrument Concepts of Europa Exploration programs) to develop methods that increase the fidelity of in situ microscopy life detection measurements through two main approaches. First, native fluorescence is excited in molecules that contain aromatic moieties such as proteins (using deep UV excitation), and energy carrying molecules and endogenous chromophores (using visible-light excitation), to correlate the location of these species with cell-like structural features (brightfield imaging). Second, fluorescent stains are used to selectively image cells and cell fragments by targeting proteins, lipids, and nucleic acids. We discuss the results of tests, obtained using ocean world analog samples, that have examined trades associated with implementing these methods autonomously in planetary missions, including the intrinsic properties of candidate fluorescence dyes and long-term storage and radiation stability.

Pavel E Z Klier↗
NASA NTRS2016

Food Fortification Stability Study

This study aims to assess the stability of vitamin content, sensory acceptability and color variation in fortified spaceflight foods over a period of 2 years. Findings will identify optimal formulation, processing, and storage conditions to maintain stability and acceptability of commercially available fortification nutrients. Changes in food quality are being monitored to indicate whether fortification affects quality over time (compared to the unfortified control), thus indicating their potential for use on long-duration missions.

Sirmons, T. A.↗
NASA NTRS2017

Food Fortification Stability Study

This study aimed to assess the stability of vitamin content, sensory acceptability and color variation in fortified spaceflight foods over a period of two years. Findings will help to identify optimal formulation, processing, and storage conditions to maintain stability and acceptability of commercially available fortification nutrients. Changes in food quality were monitored to indicate whether fortification affects quality over time (compared to the unfortified control), thus indicating their potential for use on long-duration missions.

Sirmons, T. A.↗
NASA NTRS1984

Related Studies in Long Term Lithium Battery Stability

The continuing growth of the use of lithium electrochemical systems in a wide variety of both military and industrial applications is primarily a result of the significant benefits associated with the technology such as high energy density, wide temperature operation and long term stability. The stability or long term storage capability of a battery is a function of several factors, each important to the overall storage life and, therefore, each potentially a problem area if not addressed during the design, development and evaluation phases of the product cycle. Design (e.g., reserve vs active), inherent material thermal stability, material compatibility and self-discharge characteristics are examples of factors key to the storability of a power source.

Horning, R. J.↗
NASA NTRS2018

Extension of Space Food Shelf Life Through Hurdle Approach

The processed and prepackaged space food system is the main source of crew nutrition, and hence central to astronaut health and performance. Unfortunately, space food quality and nutrition degrade to unacceptable levels in two to three years with current food stabilization technologies. Future exploration missions will require a food system that remains safe, acceptable and nutritious through five years of storage within vehicle resource constraints. The potential of stabilization technologies (alternative storage temperatures, processing, formulation, ingredient source, packaging, and preparation procedures), when combined in hurdle approach, to mitigate quality and nutritional degradation is being assessed. Sixteen representative foods from the International Space Station food system were chosen for production and analysis and will be evaluated initially and at one, three, and five years with potential for analysis at seven years if necessary. Analysis includes changes in color, texture, nutrition, sensory quality, and rehydration ratio when applicable. The food samples will be stored at -20 C, 4 C, and 21 C. Select food samples will also be evaluated at -80 C to determine the impacts of ultra-cold storage after one and five years. Packaging film barrier properties and mechanical integrity will be assessed before and after processing and storage. At the study conclusion, if tested hurdles are adequate, formulation, processing, and storage combinations will be uniquely identified for processed food matrices to achieve a five-year shelf life. This study will provide one of the most comprehensive investigations of long duration food stability ever completed, and the achievement of extended food system stability will have profound impacts to health and performance for spaceflight crews and for relief efforts and military applications on Earth.

Cooper, M. R.↗
NASA NTRS1983

Radioactive nuclear waste stabilization - Aspects of solid-state molecular engineering and applied geochemistry

Stabilization techniques for the storage of radioactive wastes are surveyed, with emphasis on immobilization in a primary barrier of synthetic rock. The composition, half-life, and thermal-emission characteristics of the wastes are shown to require thermally stable immobilization enduring at least 100,000 years. Glass materials are determined to be incapable of withstanding the expected conditions, average temperatures of 100-500 C for the first 100 years. The geological-time stability of crystalline materials, ceramics or synthetic rocks, is examined in detail by comparing their components with similar naturally occurring minerals, especially those containing the same radioactive elements. The high-temperature environment over the first 100 years is seen as stabilizing, since it can recrystallize radiation-induced metamicts. The synthetic-rock stabilization technique is found to be essentially feasible, and improvements are suggested, including the substitution of nepheline with freudenbergite and priderite for alkaline-waste stabilization, the maintenance of low oxygen fugacity, and the dilution of the synthetic-rock pellets into an inert medium.

Haggerty, S. E.↗