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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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Lubrication performance and thermal shear degradation of polyphenyl ethers and refined mineral oils in high temperature vane pump loop
NbN thin film production by refined reactive sputtering technique, discussing Pauli spin paramagnetism and spin orbit scattering in high field superconductivity
Crew survival ensurance under emergency situations during manned space flight, discussing Apollo abort system refinements
Fluorinated polyethers are suitable lubricants for rolling-element bearings in cryogenic systems. Lubrication effectiveness is comparable to that of super-refined mineral oil lubricants operating at room temperature.
Plastic deformation of Mo-Re single crystals produced by electron beam zone refining, investigating lattice frictional stress, activation volume temperature variation, etc
Morning and evening current reversals in equatorial electrojet, discussing seasonal variation data for refining models
Photochemical etching is most successful method for obtaining simulated microwave backscatter pattern from ocean surface. Process is adaptable to integrated circuit and thin film semiconductor fabrications. The attained horizontal resolution of 10 should improve with equipment refinement.
Refined computerized plotting system produces low-cost graphic-numeric charts that illustrate fiscal data on monthly incremental or cumulative basis, or both. Output is in the form of hard copy or microfilm, or visual-aid transparencies prepared from hard copy for rapid management status presentations.
Text applies to solution of various optimization problems. Concepts are logically introduced and refinements and complexities for computerized numerical solutions are avoided. Specific topics and essential equivalence of several different approaches to various aspects of the problem are given.
A discussion is presented of the response of an airplane to turbulence, including techniques for the alleviation of lateral and longitudinal motions. A simplified theoretical treatment of the longitudinal response to vertical gusts, which allows calculation of the effects of various types of gust-alleviation systems, is presented. Flight experiments on various gust-alleviation systems are reviewed. A brief discussion is given of the application of these systems to different types of airplanes. Finally, methods of refinement of the simplified theory to include effects of horizontal gusts, unsteady lift effects, and isotropic turbulence are described.
Airbreathing hypersonic aircraft employing liquid hydrogen fuel have the potential of satisfying a number of mission requirements in the 1980-2000 time period. However, major advances in the technological state of the art are necessary before such aircraft can be considered either feasible or practical. The objective was to assess the research and development requirements for hypersonic aircraft and based on these requirements, to provide the NASA with characteristics of a number of desirable hypersonic research facilities. The study is organized in three phases. Phase I is a preliminary analysis of a broad group of concepts. The purpose of Phase I was to compare the characteristics of these facilities considering research capability, versatility, adaptability, system confidence and costs and based on these comparisons select those facilities that appear most attractive for parametric study and further refinement in Phase II. This part of Volume II presents the results of the design and cost synthesis of the flight research facilities.
The night airglow, which lies in a thin layer 70 to 100 kilometers above the earth, was studied. Although the surface brightness is low when observed through this layer from below, brightness of the airglow is augmented by a factor of approximately 35 when the airglow is viewed tangentially from the vantage point of the Gemini orbit. This augmentation phenomenon is an effective means of synoptic airglow study. The objective was to extend and refine the photographic method. The following techniques were used to achieve this goal: (1) The camera was equipped with a filter to photograph the two prominent line emissions at 5577 and 5893 A; (2) An illuminated camera sight and an aiming camera mount were used in an attempt to reduce the number of blurred photographs; (3) The number of photographs taken and the amount of the earth photographed were as large as possible; and (4) The photograph of the twilight horizon revealed a sunlit dayglow layer.
The feasibility, functionality, and overall accuracy of the use of lithium were investigated as a chemical tracer in urine for providing a means of indirect determination of total urine volume by the atomic absorption spectrophotometry method. Experiments were conducted to investigate the parameters of instrumentation, tracer concentration, mixing times, and methods for incorporating the tracer material in the urine collection bag, and to refine and optimize the urine tracer technique to comply with the Skylab scheme and operational parameters of + or - 2% of volume error and + or - 1% accuracy of amount of tracer added to each container. In addition, a back-up method for urine collection and sampling system was developed and evaluated. This back-up method incorporates the tracer technique for volume determination in event of failure of the primary urine collection and preservation system. One chemical preservative was selected and evaluated as a contingency chemical preservative for the storage of urine in event of failure of the urine cooling system.
Electronic signal generator data based on solid state concepts were simplified or refined to meet requirements, such as reliability, simplicity, fail-safe characteristics, and the capability of withstanding environmental extremes. Pulse generators, high voltage pulse generators, oscillators, analog signal generators, square wave signal generators, and special function signal generators are described.
Results are presented of investigations of soil moisture, snow cover, and lake temperatures carried out with the support of the Earth Resources Survey Program. Objectives of these studies were: (1) Obtain more data with a multifrequency microwave system so that the range of soil moisture amounts and types can be extended. (2) Establish instrument and data specifications for microwave sensing of soil moisture from satellites and aircraft. (3) Refine the procedures for mapping snow cover that have been developed using satellite and aircraft remote sensor data in the visible spectrum. (4) Evaluation of satellite and aircraft infrared observations for determining their information content with respect to snow cover, ice cover, and water temperature over large lakes.
The concentrations of 23 major, minor, and trace elements in the fecal samples from the Apollo 12 and 13 astronauts are reported. Most elemental excretion rates are comparable to rates reported for earlier missions. Exceptions are noted for calcium, iron, and tin. Body calcium and iron losses appear to be reduced during the Apollo 12 and 13 missions such that losses now seem to be insignificant. Refined measurements of tin excretion rates agree with normal dietary intakes. Earlier reported tin values are in error. A new passive dosimetry canister was designed which contains foils of tantalum, copper, titanium, iron, cobalt, aluminum, and scandium. By measuring the concentrations of the various products of nuclear reactions in these metals after space exposure, the characteristics of the incident cosmic particles can be determined.
A portable, solid state, wideband wattmeter has been developed as a general purpose type of laboratory instrument. Its circuit and component investigations and evaluation data are presented. A prototype unit was used extensively, and served as the basis for a second instrument incorporating refined circuitry and improved packaging. The wattmeter provides true four quadrant operation which permits instantaneous indication of real power as an oscilloscope display. Major performance factors are: frequency bandwidth DC to 1 MHz plus or minus 1 db; current range 10 mA to 100 amperes peak; voltage range 1 volt to 1000 volts peak; accuracy plus or minus 2% of full scale reading. Oscilloscope data for typical switching transients in a transistor inverter circuit are included.
The complex Saturn S-2 welding processes and procedures required considerable development and refinement to establish a production capability that could consistently produce aluminum alloy welds within specified requirements. The special processes and techniques are defined that were established for the welding of gore-to-gore and manhole- or closeout-to-gore.