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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 55 records · Page 3
All sourcesNASA NTRSDOE OSTI
NASA NTRS1998

X-33 Environmental Impact Statement: A Fast Track Approach

NASA is required by the National Environmental Policy Act (NEPA) to prepare an appropriate level environmental analysis for its major projects. Development of the X-33 Technology Demonstrator and its associated flight test program required an environmental impact statement (EIS) under the NEPA. The EIS process is consists of four parts: the "Notice of Intent" to prepare an EIS and scoping; the draft EIS which is distributed for review and comment; the final ETS; and the "Record of Decision." Completion of this process normally takes from 2 - 3 years, depending on the complexity of the proposed action. Many of the agency's newest fast track, technology demonstration programs require NEPA documentation, but cannot sustain the lengthy time requirement between program concept development to implementation. Marshall Space Flight Center, in cooperation with Kennedy Space Center, accomplished the NEPA process for the X-33 Program in 13 months from Notice of Intent to Record of Decision. In addition, the environmental team implemented an extensive public involvement process, conducting a total of 23 public meetings for scoping and draft EIS comment along with numerous informal meetings with public officials, civic organizations, and Native American Indians. This paper will discuss the fast track approach used to successfully accomplish the NEPA process for X-33 on time.

McCaleb, Rebecca C.↗
NASA NTRS2001

Effects of chair restraint on the strength of the tibia in rhesus monkeys

To determine the effects of the relative inactivity and unloading on the strength of the tibias of monkeys, Macaca mulatta, we used a non-invasive test to measure bending stiffness, or EI (Nm2), a mechanical property. The technique was validated by comparisons of in vivo measurements with standard measures of EI in the same bones post-mortem (r2 = 0.95, P < 0.0001). Inter-test precision was 4.28+/-1.4%. Normative data in 24 monkeys, 3.0+/-0.7 years and 3.6+/-0.6 kg, revealed EI to be 16% higher in the right than left tibia (4.4+/-1.6 vs. 3.7+/-1.6 Nm2, P < 0.05). Five monkeys, restrained in chairs for 14 days, showed decreases in EI. There were no changes in EI in two chaired monkeys that lost weight during a 2-week space flight. The factors that account for both the decreases in bone mechanical properties after chair restraint at 1 g and lack of change after microgravity remain to be identified. Metabolic factors associated with body weight changes are suggested by our results.

NASA Discipline Musculoskeletal↗
NASA NTRS1992

In vivo assessment of forearm bone mass and ulnar bending stiffness in healthy men

The cross-sectional bending stiffness EI of the ulna was measured in vivo by mechanical resistance tissue analysis (MRTA) in 90 men aged 19-89 years. MRTA measures the impedance response of low-frequency vibrations to determine EI, which is a reflection of elastic modulus E and moment of inertia I for the whole ulna. EI was compared to conventional estimates of bone mineral content (BMC), bone width (BW), and BMC/BW, which were all measured by single-photon absorptiometry. Results obtained from the nondominant ulna indicate that BW increases (r = 0.27, p = 0.01) and ulnar BMC/BW decreases (r = -0.31, p < or = 0.005) with age. Neither BMC nor EI declined with age. The single best predictor of EI was BW (r2 = 0.47, p = 0.0001), and further small but significant contributions were made by BMC (r2 = 0.53, p = 0.0001) and grip strength (r2 = 0.55, p = 0.0001). These results suggest that the resistance of older men to forearm fracture is related to age-associated changes in the moment of inertia achieved by redistributing bone mineral farther from the bending axis. We conclude that the in vivo assessment of bone geometry offers important insights to the comprehensive evaluation of bone strength.

NASA Center ARC↗
NASA NTRS2004

Electrochemical Impedance Spectroscopy of Alloys in a Simulated Space Shuttle Launch Environment

Type 304L stainless steel (304L SS) tubing is currently used in various supply lines that service the Orbiter at NASA's John F. Kennedy Space Center Launch Pads in Florida (USA). The atmosphere at the Space Shuffle launch site is very corrosive due to a combination of factors, such as the proximity of the Atlantic Ocean and the concentrated hydrochloric acid produced by the fuel combustion reaction in the solid rocket boosters. The acidic chloride environment is aggressive to most metals and causes severe pitting in many of the common stainless steel alloys such as 304L SS. Stainless steel tubing is susceptible to pitting corrosion that can cause cracking and rupture of both high-pressure gas and fluid systems. Outages in the systems where failures occur can impact the normal operation of the shuttle and launch schedules. The use of a more corrosion resistant tubing alloy for launch pad applications would greatly reduce the probability of failure, improve safety, lessen maintenance costs, and reduce downtime. A study which included ten alloys was undertaken to find a more corrosion resistant material to replace the existing 304L SS tubing. The study included atmospheric exposure at NASA's John F. Kennedy Space Center outdoor corrosion test site near the launch pads and electrochemical measurements in the laboratory which included DC techniques and electrochemical impedance spectroscopy (EIS). This paper presents the results from EIS measurements on three of the alloys: AL6XN (UN N08367), 254SMO (UNS S32l54), and 304L SS (UNS S30403). Type 304L SS was included in the study as a control. The alloys were tested in three electrolyte solutions which consisted of neutral 3.55% NaC1, 3.55% NaCl in O.1N HC1, and 3.55% NaCl in 1.ON HC1. The solutions were chosen to simulate environments that were expected to be less, similar, and more aggressive, respectively, than those present at the Space Shuttle launch pads. The results from the EIS measurements were analyzed to evaluate the corrosion susceptibility of the alloys and to predict the long-term corrosion performance of the subject materials. The results from the EIS measurements for the three alloys indicated that the higher-alloyed 254SMO and AL6XN exhibited a significantly improved resistance to corrosion than the 304L SS as the concentration of hydrochloric acid in the 3.55% NaC1 solution was increased. The polarization resistance values obtained from the EIS measurements were consistent with those from linear polarization measurements, and were indicative of the actual long-term corrosion performance of the alloys during a two-year atmospheric exposure study.

Calle, L. M.↗
NASA NTRS2022

Re-Evaluation of Low Cloud Amount Relationships With Lower-Tropospheric Stability and Estimated Inversion Strength

Lower-tropospheric stability (LTS) and estimated inversion strength (EIS) have a widely accepted relationship with low cloud amount and are key observational foundations for understanding and modeling low-level stratiform clouds. Using the updated surface-based and satellite cloud data, we find that low cloud amount is not as strongly correlated with LTS, and not as sensitive to LTS, as established in the past. EIS does not provide a stronger correlation with low cloud amount than LTS over all eight regions (including the midlatitudes). Further analyzing the relationships between LTS and EIS with different types of low clouds, we find that there is a strong correlation of LTS and EIS with stratocumulus only. This explains the weaker correlation of low cloud fraction (including cumulus, stratocumulus, and stratus) to both LTS and EIS. These results also suggest the need to re-evaluate these relationships in Earth system models. Plain Language Summary: Low-level clouds play an important role in the global radiation budget. Low cloud amount has two established linear relationships with lower-tropospheric stability (LTS) and estimated inversion strength (ETS). These two relationships are re-evaluated here using three separate observational cloud and two reanalysis datasets for three distinct but overlapping time periods. The analysis shows that the strength of the LTS and ETS relationships with low cloud amount varies, depending on the cloud data used. They have a strong relationship with stratocumulus cloud amount only.

Lauren Cutler↗
NASA NTRS1975

CARETS: A prototype regional environmental information system. Volume 11: Potential usefulness of CARETS data for environmental impact assessment

The National Environmental Policy Act of 1969 requires that Federal agencies prepare environmental impact statements (EIS) for all proposed actions that significantly affect the quality of the environment. The EIS builds a predictive model of beneficial or adverse changes resulting from an action. Environmental impact statement preparation requires identification of environmental, social, and economic conditions likely to change and also requires prediction of intensity and spatial dimensions of changes. The Central Atlantic Regional Ecological Test Site (CARETS) project has produced land use data that can be of value for such assessment. To ascertain the types of proposed actions requiring EIS's, all EIS's prepared for proposed actions in the test site between January 1970 and June 1974 were reviewed. The actions were divided into seven categories: (1) construction of transportation and communication facilities; (2) construction of power plant, powerline, and fuel line facilities; (3) urban renewal, new town development projects, and multistory building construction; (4) construction of facilities for watershed protection and development;, (5) construction of waste treatment and disposal facilities (6) maintenance dredging, navigation improvements, and beach erosion control and replenishment projects; and (7) establishing or enhancing land and water conservation areas. Examples of actions from each category were selected for more detailed study. In view of the types of projects being proposed, an approach to environmental impact assessment using land use and water data as central inputs was recommended. The viability of such an approach as well as other approaches depends upon the availability of quantitative data such as those produced by the CARETS project.

Environmental impact assessment↗
NASA NTRS1992

The platinum microelectrode/Nafion interface - An electrochemical impedance spectroscopic analysis of oxygen reduction kinetics and Nafion characteristics

The objectives of this study were to use electrochemical impedance spectroscopy (EIS) to study the oxygen-reduction reaction under lower humidification conditions than previously studied. The EIS technique permits the discrimination of electrode kinetics of oxygen reduction, mass transport of O2 in the membrane, and the electrical characteristics of the membrane. Electrode-kinetic parameters for the oxygen-reduction reaction, corrosion current densities for Pt, and double-layer capacitances were calculated. The production of water due to electrochemical reduction of oxygen greatly influenced the EIS response and the electrode kinetics at the Pt/Nafion interface. From the finite-length Warburg behavior, a measure of the diffusion coefficient of oxygen in Nafion and diffusion-layer thickness was obtained. An analysis of the EIS data in the high-frequency domain yielded membrane and interfacial characteristics such as ionic conductivity of the membrane, membrane grain-boundary capacitance and resistance, and uncompensated resistance.

Parthasarathy, Arvind↗
NASA NTRS2000

Bioimpedance Measurement of Segmental Fluid Volumes and Hemodynamics

Bioimpedance has become a useful tool to measure changes in body fluid compartment volumes. An Electrical Impedance Spectroscopic (EIS) system is described that extends the capabilities of conventional fixed frequency impedance plethysmographic (IPG) methods to allow examination of the redistribution of fluids between the intracellular and extracellular compartments of body segments. The combination of EIS and IPG techniques was evaluated in the human calf, thigh, and torso segments of eight healthy men during 90 minutes of six degree head-down tilt (HDT). After 90 minutes HDT the calf and thigh segments significantly (P < 0.05) lost conductive volume (eight and four percent, respectively) while the torso significantly (P < 0.05) gained volume (approximately three percent). Hemodynamic responses calculated from pulsatile IPG data also showed a segmental pattern consistent with vascular fluid loss from the lower extremities and vascular engorgement in the torso. Lumped-parameter equivalent circuit analyses of EIS data for the calf and thigh indicated that the overall volume decreases in these segments arose from reduced extracellular volume that was not completely balanced by increased intracellular volume. The combined use of IPG and EIS techniques enables noninvasive tracking of multi-segment volumetric and hemodynamic responses to environmental and physiological stresses.

Montgomery, Leslie D.↗
NASA NTRS1996

Differences in Mechanical Properties of the Human and Monkey Tibia

A method which uses an instrument that detects the response of a long bone to a vibratory stimulus to quantify mechanical properties non-invasively was revised and validated for use in the tibia. Stored data from healthy men was reanalyzed and compared with values from non-human primates. The analysis uses the relationship K(sub b) = 48 EI/L(sup 3) where K(sub b) is the lateral stiffness of a beam with force applied midspan, E is the elastic modulus, I the geometric moment of inertia and L, the limb length. Values for stiffness (EI, Nm(sup2)), the Euler buckling load (P(sub cr) = EI (pi/L)(sup 2)), and bone sufficiency (S) which represents the axial load the bone can support, adjusted to BW (S=P(sub cr)/BW) were obtained. The interest precision of the method in relaxed men, 5.8%, and in sedated male monkeys, 4.3%, was based on repeated measures in the same subjects at 1 month intervals. The R tibias of 40 men, aged 38.6 +/- 7.3 yrs with BW 78.9 +/- 7.9 kg, showed average (+/- SD) L to be 35 +/- 2 cm, EI 222 +/- 71 Nm(sup 2), P(sub cr) 18.1 +/- 4.9 kN, and S 23.4 +/- 5.7 N. The R tibias of 24 Rhesus monkeys ranging in age from 2-12 years, BW 4.9 +/- 3 kg, showed L to be 14.7 +/- 1.9 cm, EI 6.0 +/- 4.8 Nm(sup 2), P(sub cr) 2.51 +/- 1.2 kN and S 57.3 N. These measurements indicate that the tibia of a terrestrial non-human primate, M. mulatta, has higher load carrying capacity for the level of body weights in the species than the human bone.

Arnaud, Sara B.↗
NASA NTRS2016

Orion Exploration Mission Entry Interface Target Line

The Orion Multi-Purpose Crew Vehicle is required to return to the continental United States at any time during the month. In addition, it is required to provide a survivable entry from a wide range of trans-lunar abort trajectories. The Entry Interface (EI) state must be targeted to ensure that all requirements are met for all possible return scenarios, even in the event of no communication with the Mission Control Center to provide an updated EI target. The challenge then is to functionalize an EI state constraint manifold that can be used in the on-board targeting algorithm, as well as the ground-based trajectory optimization programs. This paper presents the techniques used to define the EI constraint manifold and to functionalize it as a set of polynomials in several dimensions.

Rea, Jeremy R.↗
NASA NTRS2017

On the Impact of Granularity of Space-Based Urban CO2 Emissions in Urban Atmospheric Inversions: A Case Study for Indianapolis, IN

Quantifying greenhouse gas (GHG) emissions from cities is a key challenge towards effective emissions management. An inversion analysis from the INdianapolis FLUX experiment (INFLUX) project, as the first of its kind, has achieved a top-down emission estimate for a single city using CO2 data collected by the dense tower network deployed across the city. However, city-level emission data, used as a priori emissions, are also a key component in the atmospheric inversion framework. Currently, fine-grained emission inventories (EIs) able to resolve GHG city emissions at high spatial resolution, are only available for few major cities across the globe. Following the INFLUX inversion case with a global 1x1 km ODIAC fossil fuel CO2 emission dataset, we further improved the ODIAC emission field and examined its utility as a prior for the city scale inversion. We disaggregated the 1x1 km ODIAC non-point source emissions using geospatial datasets such as the global road network data and satellite-data driven surface imperviousness data to a 3030 m resolution. We assessed the impact of the improved emission field on the inversion result, relative to priors in previous studies (Hestia and ODIAC). The posterior total emission estimate (5.1 MtC/yr) remains statistically similar to the previous estimate with ODIAC (5.3 MtC/yr). However, the distribution of the flux corrections was very close to those of Hestia inversion and the model-observation mismatches were significantly reduced both in forward and inverse runs, even without hourly temporal changes in emissions. EIs reported by cities often do not have estimates of spatial extents. Thus, emission disaggregation is a required step when verifying those reported emissions using atmospheric models. Our approach offers gridded emission estimates for global cities that could serves as a prior for inversion, even without locally reported EIs in a systematic way to support city-level Measuring, Reporting and Verification (MRV) practice implementation.

EIs↗
NASA NTRS1990

Draft Environmental Impact Statement for the Ulysses Mission (Tier 2)

This Draft Environmental Impact Statement (DEIS) addresses the environmental impacts which may be caused by the preparation and operation of the Ulysses spacecraft, including its planned launch on the Space Transportation System (STS) Shuttle and the alternative of canceling further work on the mission. The launch configuration will use the STS/Inertial Upper Stage (IUS)/Payload Assist Module-Special(PAM-S) combination. The Tier 1 EIS included a delay alternative which considered the Titan 4 launch vehicle as an alternative booster stage for launch in 1991 or later. However, the U.S. Air Force, which procures the Titan 4 for NASA, could not provide a Titan 4 vehicle for the 1991 launch opportunity because of high priority Department of Defense requirements. The only expected environmental effects of the proposed action are associated with normal Shuttle launch operations. These impacts are limited largely to the near-field at the launch pad, except for temporary stratospheric ozone effects during launch and occasional sonic boom effects near the landing site. These effects have been judged insufficient to preclude Shuttle launches. In the event of (1) an accident during launch, or (2) reentry of the spacecraft from earth orbit, there are potential adverse health and environmental effects associated with the possible release of plutonium dioxide from the spacecraft's radioisotope thermoelectric generators (RTG). The potential effects considered in this EIS include risks of air and water quality impacts, local land area contamination, adverse health and safety impacts, the disturbance of biotic resources, impacts on wetland areas or areas containing historical sites, and socioeconomic impacts. Intensive analysis of the possible accidents associated with the proposed action are underway and preliminary results indicate small health or environmental risks. The results of a Final Safety Analysis Report will be available for inclusion into the final EIS.

Source record↗
NASA NTRS1995

Advanced Subsonic Airplane Design and Economic Studies

A study was made to examine the effect of advanced technology engines on the performance of subsonic airplanes and provide a vision of the potential which these advanced engines offered. The year 2005 was selected as the entry-into-service (EIS) date for engine/airframe combination. A set of four airplane classes (passenger and design range combinations) that were envisioned to span the needs for the 2005 EIS period were defined. The airframes for all classes were designed and sized using 2005 EIS advanced technology. Two airplanes were designed and sized for each class: one using current technology (1995) engines to provide a baseline, and one using advanced technology (2005) engines. The resulting engine/airframe combinations were compared and evaluated on the basis on sensitivity to basic engine performance parameters (e.g. SFC and engine weight) as well as DOC+I. The advanced technology engines provided significant reductions in fuel burn, weight, and wing area. Average values were as follows: reduction in fuel burn = 18%, reduction in wing area = 7%, and reduction in TOGW = 9%. Average DOC+I reduction was 3.5% using the pricing model based on payload-range index and 5% using the pricing model based on airframe weight. Noise and emissions were not considered.

Liebeck, Robert H.↗
NASA NTRS1996

Final Tier 2 Environmental Impact Statement for International Space Station

The Final Tier 2 Environmental Impact Statement (EIS) for the International Space Station (ISS) has been prepared by the National Aeronautics and Space Administration (NASA) and follows NASA's Record of Decision on the Final Tier 1 EIS for the Space Station Freedom. The Tier 2 EIS provides an updated evaluation of the environmental impacts associated with the alternatives considered: the Proposed Action and the No-Action alternative. The Proposed Action is to continue U.S. participation in the assembly and operation of ISS. The No-Action alternative would cancel NASA!s participation in the Space Station Program. ISS is an international cooperative venture between NASA, the Canadian Space Agency, the European Space Agency, the Science and Technology Agency of Japan, the Russian Space Agency, and the Italian Space Agency. The purpose of the NASA action would be to further develop human presence in space; to meet scientific, technological, and commercial research needs; and to foster international cooperation.

Source record↗
NASA NTRS1995

Draft Tier 2 Environmental Impact Statement for International Space Station

The Draft Tier 2 Environmental Impact Statement (EIS) for the International Space Station (ISS) has been prepared by the National Aeronautics and Space Administration (NASA) and follows NASA's Record of Decision on the Final Tier 1 EIS for the Space Station Freedom. The Tier 2 EIS provides an updated evaluation of the environmental impacts associated with the alternatives considered: the Proposed Action and the No-Action alternative. The Proposed Action is to continue U.S. participation in the assembly and operation of ISS. The No-Action alternative would cancel NASA's participation in the Space Station Program. ISS is an international cooperative venture between NASA, the Canadian Space Agency, the European Space Agency, the Science and Technology Agency of Japan, the Russian Space Agency, and the Italian Space Agency. The purpose of the NASA action would be to further develop a human presence in space; to meet scientific, technological, and commercial research needs; and to foster international cooperation.

Source record↗
NASA NTRS1996

Electrochemical Impedance Spectroscopy of Conductive Polymer Coatings

Electrochemical impedance spectroscopy (EIS) was used to investigate the corrosion protection performance of twenty nine proprietary conductive polymer coatings for cold rolled steel under immersion in 3.55 percent NaCl. Corrosion potential as well as Bode plots of the data were obtained for each coating after one hour immersion, All coatings, with the exception of one, have a corrosion potential that is higher in the positive direction than the corrosion potential of bare steel under the same conditions. Group A consisted of twenty one coatings with Bode plots indicative of the capacitive behavior characteristic of barrier coatings. An equivalent circuit consisting of a capacitor in series with a resistor simulated the experimental EIS data for these coatings very well. Group B consisted of eight coatings that exhibited EIS spectra showing an inflection point which indicates that two time constants are present. This may be caused by an electrochemical process taking place which could be indicitive of coating failing. These coatings have a lower impedance that those in Group A.

Calle, Luz Marina↗
NASA NTRS1997

Relative to the Caltech Electron/Isotope Spectrometer-IMP

The Electron Isotope Spectrometers (EIS) on IMP-8 was designed to provide measurements of low energy isotopes from H to O (1 less than or equal to Z less than or equal to 8) over the energy range from approx. 2 to approx. 40 MeV/nuc, as well as low energy electrons from approx. 0.2 to approx. 6 MeV. These measurements supported studies of the acceleration and transport of energetic particles originating on the Sun, in interplanetary space, in the Galaxy, and in Earth's and Jupiter's magnetosphere. IMP-8 was launched in October 1973 and still continues to provide key particles and fields measurements from orbit about the Earth. The IMP-8 EIS continued to operate flawlessly until 8/3/92, when a partial failure was suffered in a bias supply, which reduced the ability of the instrument to measure high energy particles. The EIS was subsequently turned off in 1995. A nearly identical instrument was flown on IMP-7 from 10/92 to 7/96, and many studies combined results from both instruments. For completeness, this report summarizes scientific results and publications from the entire IMP-7&8 effort, not just from the period covered by NAG5-727.

Source record↗
NASA NTRS1999

Airborne Observations of Aerosol Emissions from F-16 Aircraft

We presented results from the SASS Near-Field Interactions Flight (SNIF-III) Experiment which was conducted during May and June 1997 in collaboration with the Vermont and New Jersey Air National Guard Units. The project objectives were to quantify the fraction of fuel sulfur converted to S(VI) species by jet engines and to gain a better understanding of particle formation and growth processes within aircraft wakes. Size and volatility segregated aerosol measurements along with sulfur species measurements were recorded in the exhaust of F-16 aircraft equipped with F-100 engines burning fuels with a range of fuel S concentrations at different altitudes and engine power settings. A total of 10 missions were flown in which F-16 exhaust plumes were sampled by an instrumented T-39 Sabreliner aircraft. On six of the flights, measurements were obtained behind the same two aircraft, one burning standard JP-8 fuel and the other either approximately 28 ppm or 1100 ppm S fuel or an equal mixture of the two (approximately 560 ppm S). A pair of flights was conducted for each fuel mixture, one at 30,000 ft altitude and the other starting at 35,000 ft and climbing to higher altitudes if contrail conditions were not encountered at the initial flight level. In each flight, the F-16s were operated at two power settings, approx. 80% and full military power. Exhaust emissions were sampled behind both aircraft at each flight level, power setting, and fuel S concentration at an initial aircraft separation of 30 m, gradually widening to about 3 km. Analyses of the aerosol data in the cases where fuel S was varied suggest results were consistent with observations from project SUCCESS, i.e., a significant fraction of the fuel S was oxidized to form S(VI) species and volatile particle emission indices (EIs) in comparably aged plumes exhibited a nonlinear dependence upon the fuel S concentration. For the high sulfur fuel, volatile particle EIs in 10-second-old-plumes were 2 to 3 x 10 (exp 17) / kg of fuel burned and exhibited no obvious trend with engine power setting or flight altitude. In contrast, about 8-fold fewer particles were observed in similarly aged plumes from the same aircraft burning fuel with 560 ppm S content and EIs of 1 x 10(exp 15)/ kg of fuel burned were observed in the 28 ppm S fuel case. Moreover, data recorded as a function of plume age indicates that formation and growth of the volatile particles proceeds more slowly as the fuel S level is reduced. For example, ultrafine particle concentrations appear to stabilize within 5 seconds after emission in the 1100 ppm S cases but are still increasing in 20-second old plumes produced from burning the 560 ppm S fuel.

Anderson, B. E.↗