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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 19 records
All sourcesNASA NTRSDOE OSTI
NASA NTRS1963

LOW-ENERGY TRAPPED PROTONS

Proton pitch angle distributions, integral spectra, directional intensities of low energy trapped protons by explorer xii during a magnetic storm

EXPLORER XII SATELLITE↗
NASA NTRS1961

Two Instruments for Measuring Distributions of Low-Energy Charged Particles in Space

Current estimates indicate that the bulk of interplanetary gas consists of protons with energies between 0 and 20 kev and concentrations of 1 to 105 particles/cu cm. Methods and instrumentation for measuring the energy and density distribution of such a gas are considered from the standpoint of suitability for space vehicle payloads. It is concluded that electrostatic analysis of the energy distribution can provide sufficient information in initial experiments. Both magnetic and electrostatic analyzers should eventually be used. Several instruments designed and constructed at the Ames Research Center for space plasma measurements, and the methods of calibration and data reduction are described. In particular, the instrument designed for operation on solar cell power has the following characteristics: weight, 1.1 pounds; size, 2 by 3 by 4 inches; and power consumption, 145 mw. The instrument is designed to yield information on the concentration, energy distribution, and the anisotropy of ion trajectories in the 0.2 to 20 kev range.

Bader, Michel↗
NASA NTRS1962

Correlation of Resonance Charge Exchange Cross-Section Data in the Low-Energy Range

During the course of a literature survey concerning resonance charge exchange, an unusual degree of agreement was noted between an extrapolation of the data reported by Kushnir, Palyukh, and Sena and the data reported by Ziegler. The data of Kushnir et al. are for ion-atom relative energies from 10 to 1000 ev, while the data of Ziegler are for a relative energy of about 1 ev. Extrapolation of the data of Kushnir et al. was made in accordance with Holstein's theory, 3 which is a combination of time-dependent perturbation methods and classical orbit theory. The results of this theory may be discussed in terms of a critical impact parameter b(sub c).

Sheldon, John W.↗
NASA NTRSDate not supplied

Evaluation of Low-Energy Hydrogen Separation Method Using Metal-Organic Frameworks (MOFs) for Closed-Loop ECLSS Air Revitalization (CLEAR)

The State-of-the-Art (SOA) air revitalization architecture onboard the International Space Station (ISS) recovered approximately 50% of the oxygen (O 2 ) from metabolic carbon dioxide (CO 2 ) via the Sabatier process from 2011 to 2017. O 2 recovery is currently constrained by the limited availability of reactant hydrogen (H 2 ) preventing complete conversion of CO 2 to H 2 O. Increasing O 2 recovery within Closed-Loop ECLSS is essential to reducing resupply mass for long-duration manned missions; specifically focusing on water (H 2 O) which supplies H 2 for Sabatier via water electrolysis. Past ground test endeavors at Marshall Space Flight Center (MSFC) have attempted to recover H 2 from Sabatier-produced CH 4 using technologies such as carbon vapor deposition (CVD) and plasma pyrolysis. The byproducts of these technologies can act as a catalyst poison or reactor deadload to the Sabatier reactor. Hydrogen separation techniques must be utilized to maintain the Sabatier catalyst during gas recycling and must be scalable, non-energy intensive, and safe to operate in a habitation setting. Research indicated that metal-organic frameworks (MOFs) could meet these criteria and were tested for their capability to capture the various carbon-based gaseous products of CVD and plasma pyrolysis such as acetylene (C 2 H 2 ), ethylene (C 2 H 4 ), ethane (C 2 H 6 ), and carbon monoxide (CO) which would purify the hydrogen gas stream passing through the MOF. A sub-scale adsorption column was developed by Marshall Space Flight Center to test three MOF candidates against a synthetic gas mixture comprised of process-relevant carbonous gases and hydrogen to evaluate the separation capability of the MOFs. The results of the hydrogen separation capability, isothermal desorption capability, and demonstrated cyclic reuse of the MOF are presented in this paper.

Kagen Crawford↗
NASA NTRS1961

Sputtering of Metals by Mass-Analyzed N2(+) and N(+)

Low-energy sputtering studies were conducted with the help of a specially designed ion accelerator. A high-intensity rf ion source was developed for use in conjunction with electrostatic acceleration and magnetic mass separation of ion beams in the 0 to 8 kev energy range. Beams of N(+) or N2(+) ions have been produced with intensities of 200 to 500 micro-a (approx. 1 sq cm in cross section) and energy half-widths of about 20 ev. The sputtering yields of five metals (Cu, Ni, Fe, Mo, and W) were obtained as a function of energy (0-8 kev), bombarding ion (N(+) and N2(+)), and angle of incidence (normal and 450). Results are presented and some of their theoretical implications are discussed.

Bader, Michel↗