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Results for “contamination effects”

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 145 records · Page 8
All sourcesNASA NTRSDOE OSTI
NASA NTRS1968

The welding of Saturn V.

Welding techniques from Saturn 5 booster, discussing surface contamination effect on weld strength

Hoppes, R. V.↗
NASA NTRS1969

New shield for gamma-ray spectrometry

Gamma-ray shield that can be evacuated, refilled with a clean gas, and pressurized for exclusion of airborne radioactive contaminants effectively lowers background noise. Under working conditions, repeated evacuation and filling procedures have not adversely affected the sensitivity and resolution of the crystal detector.

Brar, S. S.↗
NASA NTRS1972

Phase A reaction control system design for the Large Space Telescope (LST)

The design of a reaction control system (RCS) for the Large Space Telescope is discussed. The primary requirement for the RCS is to serve as an emergency backup control system to the primary attitude control system. A regulated gaseous nitrogen RCS was selected. The operation of the system and its individual components is described. The principal design goals of the RCS were to minimize contamination effects, make use of existing components, and modularize the system to provide ease in manned orbital maintenance.

Price, W. B.↗
NASA NTRS1976

The plume impingement test program at AEDC utilizing the S-2 ullage motors (November 1973), section 1

Proposed experiments for analyzing rocket plumes are reported. Two groups of experiments were studied: (1) those that would help define some of the parameters that characterize the plume and (2) those that would enable evaluation of some of the contamination effects of the plume environment on various items of interest. The items investigated, the purpose of the investigation, are given in tabular form.

Source record↗
NASA NTRS1976

On identifying frequencies and damping in subcritical flutter testing

Various procedures that might be used in evaluating system response characteristics as involved in subcritical flight and wind-tunnel flutter testing of aircraft are reviewed with emphasis on the means for eliminating or minimizing the contamination effects produced by an unknown noise in the input. Results of a procedure developed for identifying modal frequency and damping values, and a possible way for making a detailed evaluation of system parameters, are also given.

Houbolt, J. C.↗
NASA NTRS1981

Comparative analysis of CCMHD power plants

A study of Closed Cycle MHD (CCMHD) power generation systems has been conducted which emphasizes both advances in component conceptual design and overall system performance. New design data are presented for the high temperature, regenerative argon heaters (HTRH) and the heat recovery/seed recovery (HRSR) subsystem. Contamination of the argon by flue gas adsorbed in the HTRH is examined and a model for estimation of contamination effects in operating systems is developed. System performance and cost data have been developed for the standard CCMHD/steam cycle as powered by both direct fired cyclone combustors and selected coal gasifiers. In addition, a new CCMHD thermodynamic cycle has been identified.

Alyea, F. N.↗
NASA NTRS1983

Future outlook and comments

The events of the workshop panel sessions are summarized and a synopsis of the future of the shuttle and the shuttle environment is given. Comments and projections in a number of areas addressed include: environmental measurements, contamination effects, orbiter constraints on deployable payloads, documentation and environmental information, ultraviolet experiments, infrared experiments, plasma experiments, and shuttle lidar.

Lehmann, J.↗
NASA NTRS1982

NASA-ESA Spacelab systems and programs; Proceedings of the Seminar, Washington, DC, April 23, 24, 1981

Topics discussed include the development status of the Space Shuttle and Spacelab, with attention to Spacelab subsystem performance capabilities and Shuttle-Spacelab flight operations; Spacelab data management and software for science applications, ESA and Space Shuttle pointing systems, and the Space Shuttle's Office of Space and Terrestrial Applications (OSTA)-1 payload. Also covered are the lessons learned from the first Spacelab mission, the pallet-only mode verification flight of the second Spacelab mission, the objectives of the Spacelab mission D1, its role in the German space program, and its implementation, the impact of Spacelab on space-based life sciences research, the high resolution, large area modular reflector array X-ray telescope to be used by Spacelab, and Space Shuttle contamination effects on UV coronagraphic observations.

Moore, J. W.↗
NASA NTRS1982

Sampling theory for asynoptic satellite observations. I Space-time spectra, resolution, and aliasing. II - Fast Fourier synoptic mapping

An evaluation of the information content of asynoptic data taken in the form of nadir sonde and limb scan observations is presented, and a one-to-one correspondence is established between the alias-free data and twice-daily synoptic maps. Attention is given to space and time limitations of sampling and the orbital geometry is discussed. The sampling pattern is demonstrated to determine unique space-time spectra at all wavenumbers and frequencies. Spectral resolution and aliasing are explored, while restrictions on sampling and information content are defined. It is noted that irregular sampling at high latitudes produces spurious contamination effects. An Asynoptic Sampling Theorem is thereby formulated, as is a Synoptic Retrieval Theorem, in the second part of the article. In the latter, a procedure is developed for retrieving the unique correspondence between the asymptotic data and the synoptic maps. Applications examples are provided using data from the Nimbus-6 satellite.

Salby, M. L.↗
NASA NTRS1982

Sputtering of Al2O3 and LiNbO3 in the electronic stopping region

Because of recent interest in the role played by the thermal properties of materials that exhibit high energy sputtering, Al2O3 and LiNbO3 were sputtered with chlorine ions at energies between 3 MeV and 25 MeV. To detect the sputtered Al and Nb we employ thin carbon catcher foils, which are analyzed with Rutherford scattering in the forward direction. Al surface densities of 10 to the 14th/sq cm and Nb surface densities of 10 to the 13th/sq cm are easily measured. The sputtering yields for both Al2O3 and LiNbO3 increase rapidly with increasing chlorine energy, and the Al and Nb yields are both approximately 0.2 at 20 MeV. Tests for dose, beam current, and contamination effects will be discussed.

Qiu, Y.↗