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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 415 records · Page 23
All sourcesNASA NTRSDOE OSTI
NASA NTRS1980

Effect of Ablation of Area Postrema on Frequency and Latency of Motion Sickness-Induced Emesis in the Squirrel Monkey

Twelve young adult squirrel monkeys of the Bolivian subspecies were subjected to continuous counter-clockwise horizontal rotary motion at 25 rpm, together with a sinusoidal vertical excursion of 6 in. every 2 sec (0.5 Hz). Each animal was exposed to this motion regimen for a period of 60 min once each week for three consecutive weeks. Following the third weekly motion test bilateral ablation of the Area Postrema (AP) was performed in eight of the animals by thermal cautery. Two control animals were sham-operated after the third motion test while two additional controls were given the motion tests as noted above but were not operated. The four controls were considered as a single group for statistical analyses of results of the motion tests. After a recovery period of 30 to 40 days, and at a comparable interval in the non-operated controls, each animal was again tested for motion sensitivity for three consecutive weeks. The brains of all of the animals were then fixed by left ventriculal cardiac perfusion with Bouin's fluid and processed for histological evaluation of the bilateral AP ablation in comparison with the control brains. Five of the AP-ablated animals postoperatively were completely refractory to the motion stimuli, two exhibited a decreased number of emetic responses, and one exhibited the same number of responses before and after the AP lesions. The controls exhibited no significant difference in emetic sensitivity on the second series of three weekly tests than on the first series. The results of this investigation appear to be in agreement with the observations of Wang and Chinn in the dog indicating that the integrity of the AP (CTZ) is essential to the emetic response to motion.

Brizzee, K. R.↗
DOE OSTI2022

Report Series: Evaluation, Finding Of Effect, And Mitigation Documentation For Building 23-109, Mercury, Area 23, Nevada National Security Site, Nye County, Nevada

The U.S. Department of Energy (DOE) National Nuclear Security Administration Nevada Field Office (NNSA/NFO) plans to demolish Building 23-109, the Mercury Fire Station/Maintenance/Housing Office (Nevada State Historic Preservation Office [SHPO] Resource No. B15235) at the Nevada National Security Site (NNSS) in Nye County, Nevada. The NNSA/NFO is implementing a long-term project to modernize the town of Mercury for future mission needs. The project is considered an undertaking subject to review under Title 54 of United States Code (USC) § 306108, commonly known as Section 106 of the National Historic Preservation Act, Title 54 USC § 300101, et seq., and its implementing regulations, Title 36 of the Code of Federal Regulations (36 CFR) Part 800. In 2018, Desert Research Institute (DRI) completed an architectural survey of the town of Mercury. This effort resulted in the identification, recordation, and evaluation of the Mercury Historic District (MHD, SHPO Resource No. D230), including the identification of its contributing elements (Reno et al. 2018). The MHD was recommended eligible for listing in the National Register of Historic Places (NRHP, National Register) under the Secretary of the Interior’s (SOI) Significance Criteria A and C, as defined in 36 CFR Part 60.4, as a significant concentration of buildings and structures with a direct and important association with Cold War-era nuclear testing from 1951 through 1992. It has not been evaluated under Criteria B and D to date. As part of a larger modernization program for Mercury, the NNSA/NFO and the SHPO executed the 2018 Programmatic Agreement between the National Nuclear Security Administration Nevada Field Office and the Nevada State Historic Preservation Officer regarding Modernization and Operational Maintenance of the Nevada National Security Site, at Mercury in Nye County, Nevada (Mercury PA). The Mercury PA includes streamlined Section 106 procedures for undertakings in the MHD based on contributing element categories. Building 23-109 is identified in Appendix C of the Mercury PA as a Category I contributing element, indicating that it might be individually eligible for the NRHP. It is a historic property for the purposes of Section 106 compliance and subject to the stipulations of the Mercury PA. Per Stipulation VI of the Mercury PA, when the Area of Potential Effect (APE) for an undertaking includes Category I elements, the NNSA/NFO must evaluate the Category I elements for individual NRHP eligibility under all of the SOI Significance Criteria prior to initiating any activity that may affect the elements. The purpose of this report is to evaluate Building 23-109 as a potential individually eligible historic property in fulfillment of Stipulation VI of the Mercury PA. The evaluation detailed herein concludes that Building 23-109 is not individually eligible for listing in the NRHP. Although it retains some aspects of integrity and continues to contribute to the MHD, it is not individually significant under any of the SOI Significance Criteria.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2022

Report Series: Evaluation, Finding Of Effect, And Mitigation Documentation For Building 23-113, Mercury, Area 23, Nevada National Security Site, Nye County, Nevada

The U.S. Department of Energy (DOE) National Nuclear Security Administration Nevada Field Office (NNSA/NFO) plans to demolish Building 23-113 in Mercury (Nevada State Historic Preservation Office [SHPO] Resource No. B15236), which is on the Nevada National Security Site (NNSS) in Nye County, Nevada. Demolition of Building 23-113 is part of the long-term project to modernize the town of Mercury on the NNSS for future mission needs. The project is considered an undertaking subject to review under Title 54 of United States Code (USC) § 306108, commonly known as Section 106 of the National Historic Preservation Act, Title 54 USC § 300101, et seq., and its implementing regulations, Title 36 of the Code of Federal Regulations (36 CFR) Part 800. In 2018, Desert Research Institute (DRI) completed an architectural survey of the town of Mercury. This effort resulted in the identification, recordation, and evaluation of the Mercury Historic District (MHD, SHPO Resource No. D230), including the identification of its contributing elements (Reno et al. 2018). The MHD was recommended eligible for listing in the National Register of Historic Places (NRHP, National Register) under the Secretary of the Interior’s (SOI) Significance Criteria A and C, as defined in 36 CFR Part 60.4, as a significant concentration of buildings and structures with a direct and important association with Cold War-era nuclear testing from 1951 through 1992. It has not been evaluated under Criteria B and D to date. As part of a larger modernization program for Mercury, the NNSA/NFO and the SHPO executed the 2018 Programmatic Agreement between the National Nuclear Security Administration Nevada Field Office and the Nevada State Historic Preservation Officer regarding Modernization and Operational Maintenance of the Nevada National Security Site, at Mercury in Nye County, Nevada (the Mercury PA). The Mercury PA includes streamlined Section 106 procedures for undertakings in the MHD based on contributing element categories. Building 23-113 is identified in Appendix C of the Mercury PA as a Category I contributing element, indicating that it might be individually eligible for the NRHP. It is a historic property for the purposes of Section 106 compliance and subject to the stipulations of the Mercury PA. Per Stipulation VI of the Mercury PA, when the Area of Potential Effect (APE) for an undertaking includes Category I elements, the NNSA/NFO must evaluate the Category I elements for individual NRHP eligibility under all of the SOI Significance Criteria prior to initiating any activity that may affect the elements. Therefore, the purpose of this report is to evaluate Building 23-113 as a potential individually eligible historic property in fulfillment of Stipulation VI of the Mercury PA. The evaluation detailed herein concludes that although Building 23-113 is significant at the local level for its important role as a recreational facility on the NNSS, the building lacks sufficient integrity to convey its significance. It is not individually eligible for listing in the NRHP at any level. The building remains eligible as a contributing element to the MHD.

54 ENVIRONMENTAL SCIENCES↗
NASA NTRS1972

Analytical and experimental studies of an all specular thermal control louver system in a solar vacuum environment.

Thermal control louvers are used on the ATS-F&G spacecraft to regulate temperature by varying the effective radiating area. Since solar energy on louvers has a detrimental effect on their ability to radiate energy, an analytical and experimental program was developed to evaluate the performance of an all specular louver system as a function of sun angle and blade angle. Solar simulation tests and analyses show a maximum effective absorptance of .25 for the full open condition. The application of white paint to the blades resulted in lowering the blade temperatures by 130 C without significantly affecting the system performance.

Michalek, T. J.↗
DOE OSTI2020

Electrolyte-phobic Surface for the Next-Generation Nanostructured Battery Electrodes

Nanostructured electrodes are among the most important candidates rationally designed to enable high capacity battery chemistry. Nanostructures can solve issues such as the volume change and mechanical fragmentations. However, the high surface area they usually possess would decrease the Coulombic efficiencies, since the side chemical reactions scale with surface area. Moreover, electrodes comprised of nanomaterials have significant intakes of liquid electrolytes, which reduces the overall energy density and increases the cost of the battery. Here we present a new strategy of limiting effective surface area by introducing an “electrolyte-phobic surface”. In this study, a porous Si anode functions as a model material to demonstrate this concept. Silicon boasts high theoretical capacity, but experiences large volume change during its lithiation and delithiation processes. Porous Si can address this volume change problem with the buffer effect of its inner pores. However, porous silicon shows low initial Coulombic efficiencies and high irreversible lithium loss, owing to its intrinsic high surface area. In this report, a covalently linked perfluorinated surface coating layer on porous Si particles serves as an electrolyte-phobic protection layer, minimizing the accessible surface area for the electrolytes, decreasing the side reactions between the electrolyte and Si surface, and thus significantly enhancing the initial Coulombic efficiencies, up to ~88% compared to ~60% for the pristine porous silicon. Meanwhile, the electrolyte-phobic protection layer of Si particles keeps the silicon surface compatible with the conventional polyvinylidene fluoride (PVDF) binder, which helps to stabilize the Si electrode for long-term battery cycling.

Qian, Chenxi↗
NASA NTRS1997

Temperature, Size, and Energy of the Shoemaker-Levy 9 G-Impact Fireball

The fortunate position of the Galileo spacecraft provided us with a unique opportunity to directly observe the Shoemaker- Levy 9 impacts as they occurred on the far side of Jupiter, and we present observations of the G fireball obtained by the Near Infrared Mapping Spectrometer (NTMS). These measurements were performed using 10 spectral bands, 4 representing continua and spanning the wavelength range 1.84 to 4.38 mu. Fireball signals were evident for up to 80 sec, with the time of intensity maxima and duration being greater for longer wavelengths. Color temperatures and effective emitting areas were estimated by fitting blackbody functions at the four continuum wavelengths. Good blackbody fits were found, and their intensities at shorter wavelengths show excellent agreement with the Galileo Photopolarimeter/Radiometer measurements. Temperatures near the beginning are above 3000 K, decreasing to approximately 1000 K after 1 min. The corresponding areas range from 400 to 20,000 sq km. The effective diameter of the luminous fireball shows approximately linear time variation, at least for the first 45 sec. From the temperature-effective diameter relation we find an adiabatic coefficient of lambda = 1.2+/-0.1, much as expected from theoretical considerations. The luminosity, when integrated over the period of observations and assuming a Stephan-Boltzmann radiator, gives an above-cloud radiative energy loss of 0.48+/- 0.13 x 10(exp 25) erg.

Carlson, R. W.↗
NASA NTRS2005

Ultra-Compact Broadband High-Spurious Suppression Bandpass Filter Using Double Split-end Stepped Impedance Resonators

We propose an ultra compact single-layer spurious suppression band pass filter design which has the following benefit: 1) Effective coupling area can be increased with no fabrication limitation and no effect on the spurious response; 2) Two fundamental poles are introduced to suppress spurs; 3) Filter can be designed with up to 30% bandwidth; 4) The Filter length is reduced by at least 100% when compared to the conventional filter; 5) Spurious modes are suppressed up to at the seven times the fundamental frequency; and 6) It uses only one layer of metallization which minimize the fabrication cost.

U-Yen, Kongpop↗
NASA NTRS1964

Thermal testing of the Ranger Block III SPACECRAFT in the JPL 25 ft. space simulator

In January, 1964, a test program was begun on the thermal design of the Ranger Block III Spacecraft. The tests were performed i n the newly operational JPL 25' Space Simulator over a period of 6 months . The objectives of these tests were two-fold: A. To evaluate the 25' Space Simulator as a facility for proving the thermal design of spacecrafts, and B. To verify .the thermal design of the Ranger Block III spacecraft. These two objectives are complimentary in the test series performed and are difficult to separate into distinct categories. An important part of the first objective was to learn what type of test preparation, instrumentation, and analysis was required for the meaningful evaluation of test data from the 25' Space Simulator tests. Although some experience had been gained in testing of components and incomplete spacecrafts in smaller solar simulation chambers during the early part of the Ranger program, we knew little about testing of a complete spacecraft in the 25' Space Simulator when this test program began. Test analysis requires that the energy absorbed by various spacecraft components be known. This requires a knowledge of the area of solar absorption or sunlit area, the solar energy flux density on the area, and the effective absorptance of that area. Most of the problems encountered were associated with the determination of the last two quantities since the sunlit area may be obtained directly by inspection of spacecraft surfaces. This paper will present a discussion of our experiences during the Ranger Block III thermal test series on the Thermal Test Model (TCM). The TCM was thermally equivalent to the flight type Ranger spacecraft except for the lack of an antenna dish and solar panels. Flight type structural hardware was used with surface finishes equivalent to those of the flight spacecraft. Aluminum blocks simulated the spacecraft electronics thermal masses with resistance heaters simulating the electronic power dissipation. The discussion will be presented in a semi-chronological order and will be divided into the following areas: 1. Determination of solar simulation flux density on spacecraft surfaces. 2. Problems related to decollimation of the solar simulation source. 3. Determination of effective absorptance in the solar simulation spectrum.

SPACE SIMULATOR↗
NASA NTRS2007

Emissions from Forest Fires near Mexico City

The emissions of NOx (defined as NO (nitric oxide) + NO2 (nitrogen dioxide)) and hydrogen cyanide (HCN), per unit amount of fuel burned, from fires in the pine forests that dominate the mountains surrounding Mexico City (MC) are about 2 times higher than normally observed for forest burning. The ammonia (NH3) emissions are about average for forest burning. The upper limit for the mass ratio of NOX to volatile organic compounds (VOC) for these MC-area mountain fires was approximately 0.38, which is similar to the NOx/VOC ratio in the MC urban area emissions inventory of 0.34, but much larger than the NOx/VOC ratio for tropical forest fires in Brazil (approximately 0.068). The nitrogen enrichment in the fire emissions may be due to deposition of nitrogen-containing pollutants in the outflow from the MC urban area. This effect may occur worldwide wherever biomass burning coexists with large urban areas (e.g. the tropics, southeastern US, Los Angeles Basin). The molar emission ratio of HCN to carbon monoxide (CO) for the mountain fires was 0.012 +/- 0.007, which is 2-9 times higher than widely used literature values for biomass burning. The ambient molar ratio HCN/CO in the MC-area outflow is about 0.003 +/- 0.0003. Thus, if only mountain fires emit significant amounts of HCN, these fires may be contributing about 25% of the CO production in the MCarea (approximately 98-100 W and 19-20 N). Comparing the PM10/CO and PM2.5/CO mass ratios in the MC Metropolitan Area emission inventory (0.01 15 and 0.0037) to the PM1/CO mass ratio for the mountain fires (0.133) then suggests that these fires could produce as much as approximately 79-92% of the primary fine particle mass generated in the MC-area. Considering both the uncertainty in the HCN/CO ratios and secondary aerosol formation in the urban and fire emissions implies that about 50 +/- 30% of the "aged" fine particle mass in the March 2006 MC-area outflow could be from these fires.

Yokelson, R.↗
NASA NTRS1990

Plastic superconductor bearings any size, any shape, 77 k and up

Friction free bearings at 77 k or higher are possible using the high T(sub c) copper oxide ceramic superconductors. The conventional method for making such bearings is to use a sintered ceramic monolith. This puts great restraints on size, shape and postforming machining. The material is hard and abrasive. It's possible to grind up ceramic superconductors and suspend the granules in a suitable matrix. Mechanical properties improve and are largely dependent on the binder. The Meissner effect is confined to individual grains containing electron vortices. Tracks, rails, levitation areas and bearings can be made this way with conventional plastic molding and extruding machines or by painting. The parts are easily machined. The sacrifice is in bulk electrical conductivity. A percolating wick feel for LN2 can be used to cool remote superconductors and large areas quite effectively. A hollow spheroid or cylinder of superconductor material can be molded with the internal surfaces shielded by the Meissner effect. It might be thought of as the dc magnetic analogue of the Faraday cage and the inside can be called the Meissner space. It's selective. The ac fields are transmitted with minor attenuation. Particle size and distribution have a profound effect on final magnetic and electrical characteristics.

Reick, Franklin G.↗
NASA NTRS1991

Plastic superconductor bearings any size-any shape: 77 K and up

'Friction free' bearings at 77 K or higher are possible using the high T(sub c) copper oxide ceramic superconductors. The conventional method for making such bearings is to use a sintered ceramic monolith. This puts great restraints on size, shape, and postforming machining. The material is hard and abrasive. It is possible to grind up ceramic superconductors and suspend the granules in a suitable matrix. Mechanical properties improve and are largely dependent on the binder. The Meissner effect is confined to individual grains containing electron vortices. Tracks, rails, levitation areas, and bearings can be made this way with conventional plastic molding and extruding machines or by painting. The parts are easily machined. The sacrifice is in bulk electrical conductivity. A percolating wick feed for LN2 is used to cool remote superconductors and large areas quite effectively. A hollow spheroid or cylinder of superconductor material is molded with the internal surfaces shielded by the Meissner effect. It can be thought of as the DC magnetic analog of the Faraday cage and the inside is the 'Meissner space'. It is selective. The AC fields are transmitted with minor attenuation. Particle size and distribution have a profound effect on final magnetic and electrical characteristics.

Reick, Franklin G.↗
NASA NTRS2014

A Systems Engineering Approach to Architecture Development

Architecture development is conducted prior to system concept design when there is a need to determine the best-value mix of systems that works collectively in specific scenarios and time frames to accomplish a set of mission area objectives. While multiple architecture frameworks exist, they often require use of unique taxonomies and data structures. In contrast, this presentation characterizes architecture development using terminology widely understood within the systems engineering community. Using a notional civil space architecture example, it employs a multi-tier framework to describe the enterprise level architecture and illustrates how results of lower tier, mission area architectures integrate into the enterprise architecture. It also presents practices for conducting effective mission area architecture studies, including establishing the trade space, developing functions and metrics, evaluating the ability of potential design solutions to meet the required functions, and expediting study execution through the use of iterative design cycles.

Architecture Development↗
NASA NTRS2015

A Systems Engineering Approach to Architecture Development

Architecture development is often conducted prior to system concept design when there is a need to determine the best-value mix of systems that works collectively in specific scenarios and time frames to accomplish a set of mission area objectives. While multiple architecture frameworks exist, they often require use of unique taxonomies and data structures. In contrast, this paper characterizes architecture development using terminology widely understood within the systems engineering community. Using a notional civil space architecture example, it employs a multi-tier framework to describe the enterprise level architecture and illustrates how results of lower tier, mission area architectures integrate into the enterprise architecture. It also presents practices for conducting effective mission area architecture studies, including establishing the trade space, developing functions and metrics, evaluating the ability of potential design solutions to meet the required functions, and expediting study execution through the use of iterative design cycles.

Multi-tier Framework↗
NASA NTRS2015

A Systems Engineering Approach to Architecture Development

Architecture development is often conducted prior to system concept design when there is a need to determine the best-value mix of systems that works collectively in specific scenarios and time frames to accomplish a set of mission area objectives. While multiple architecture frameworks exist, they often require use of unique taxonomies and data structures. In contrast, this paper characterizes architecture development using terminology widely understood within the systems engineering community. Using a notional civil space architecture example, it employs a multi-tier framework to describe the enterprise level architecture and illustrates how results of lower tier, mission area architectures integrate into the enterprise architecture. It also presents practices for conducting effective mission area architecture studies, including establishing the trade space, developing functions and metrics, evaluating the ability of potential design solutions to meet the required functions, and expediting study execution through the use of iterative design cycles

Architecture Development↗
NASA NTRS1977

Static and wind-on tests of an upper-surface-blown jet-flap nozzle arrangement for use on the Quiet Clean Short-haul Experimental Engine (QCSEE)

The internal aerodynamic performance, the static turning characteristics, and the forward-speed characteristics of two 1/12-scale upper surface-blown jet-flap exhaust-nozzle arrangements designed for use on the Quiet Clean Short-Haul Experimental Engine (QCSEE) were investigated. The nozzles were equipped with interchangeable area-control side doors in the aft sidewalls of the nozzle so that the effective nozzle area could be varied over a wide range. A simulated wing was used to evaluate installation losses for the nozzles. A smoothly curved flap was attached to the trailing edge of the simulated wing to allow an evaluation of the static turning characteristics of the nozzle arrangement. Forward-speed effects on the jet turning characteristics of the QCSEE nozzles were evaluated by mounting a single engine on a semispan wing designed to be representative of a four-engine STOL transport configuration.

Phelps, A. E., III↗
NASA NTRS1966

Portable sandblaster cleans small areas

Portable sandblasting unit rapidly and effectively cleans localized areas on a metal surface. The unit incorporates a bellows enclosure, masking plate, sand container, and used sand accummulator connected to a vacuum system. The bellows is equipped with an inspection window and light for observation of the sanding operation.

Severin, H. J.↗