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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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This presentation summarizes the case for using precision assembly of space structures for efficient and cost-effective construction of large systems such as iSAT primary mirror assembly and surface applications
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Hydrogen can be electrochemically produced in microbial electrolysis cells (MECs) by current generated from bacterial anodes with a small added voltage. MECs typically use a liquid catholyte containing a buffer or salts. However, anions in these catholytes result in charge being balanced predominantly by ions other than hydroxide or protons, leading to anode acidification. To enhance only hydroxide ion transport to the anode, we developed a novel vapor-fed MEC configuration lacking a catholyte with closely spaced electrodes and an anion exchange membrane to limit the acidification. This MEC design produced a record-high sustained current density of 43.1 ± 0.6 A/m 2 and a H 2 production rate of 72 ± 2 LH 2 /L-d (cell voltage of 0.79 ± 0.00 V). There was minimal impact on MEC performance of increased acetate concentrations, solution conductivity, or anolyte buffer capacity at applied voltages up to 1.1 V, as shown by a nearly constant internal resistance of only 6.8 ± 0.3 mΩ m 2 . At applied external voltages >1.1 V, the buffer capacity impacted performance, with current densities increasing from 28.5 ± 0.6 A/m 2 (20 mM phosphate buffer solution (PBS)) to 51 ± 1 A/m 2 (100 mM PBS). Furthermore, these results show that a vapor-fed MEC can produce higher and more stable performance than liquid-fed cathodes by enhancing transport of hydroxide ions to the anode.
The charge distribution in materials at the nanoscale can often explain the origin of macroscopic properties such as localized conductivity or the plasmonic response and illuminate more fundamental changes in the microscopic structure such as changes in chemical bonding characteristics. Previously, direct visualization of the charge density with high spatial resolution was often a missing link in the formation of structure–property relationships, especially in heterogeneous materials systems. Furthermore, recent advancements in microscopy technology have enabled researchers to visualize the charge distribution in materials down to subatomic length scales. In this Technical Review, we discuss the developments in high-resolution real-space charge distribution imaging using diffraction techniques and electron microscopy, with a focus on the recent advancement of four-dimensional scanning transmission electron microscopy, electron holography, and applications to materials interfaces.
Life cycle tests of nickel-cadmium, silver- cadmium, and silver-zinc space cells
Data processing system including acquisition, handling, and final analysis for magnetic tapes for computer program of tracking station data at Goddard Space Flight Center
Life cycling test of nickel-cadmium, silver- cadmium, and silver-zinc space battery cells
Research in celestial mechanics, astrophysics, radio physics, planetary atmospheres, solar physics, and other areas of space sciences
Biological and physiological problems in aviation space medicine - decompression sickness, enzyme changes, weightlessness, fatigue, and radiation protection
Numerical differentiation and smoothing of equally and nonequally spaced experimental data in independent variable
Navigation technology, communication equipment, antenna engineering, and ground station operations for Deep Space Network /DSN/
Temperature data plots of Gemini Bravo series space suit tests
Control and stabilization of space vehicles
Deep space network tracking and radio navigation accuracy analysis, high-rate telemetry, and communications and facility engineering
Guide manual for aiding designers in selection of duct, tubing, and gasketing materials for space vehicles and missiles
Space radiation environment shielding /Spares/ codes for determining radiation dosages on board Gemini 4 and Gemini 6 spacecrafts and in model environment
Systems analyses of space erectable structure concepts for Apollo Applications Program