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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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The development and characteristics of the infrared interferometer spectrometer and radiometer (IRIS) instrument for use with the Mariner/Jupiter/Saturn space probe. The subjects discussed are: (1) the electronic design, (2) the opto-mechanical design, (3) reliability analysis, (4) quality control, and (5) program management.
The design, materials, tooling, manufacturing processes, quality control, test procedures, and results associated with the fabrication and test of graphite/epoxy metering truss structure components exhibiting a near zero coefficient of thermal expansion are described. Analytical methods were utilized, with the aid of a computer program, to define the most efficient laminate configurations in terms of thermal behavior and structural requirements. This was followed by an extensive material characterization and selection program, conducted for several graphite/graphite/hybrid laminate systems to obtain experimental data in support of the analytical predictions. Mechanical property tests as well as the coefficient of thermal expansion tests were run on each laminate under study, the results of which were used as the selection criteria for the single most promising laminate. Further coefficient of thermal expansion measurement was successfully performed on three subcomponent tubes utilizing the selected laminate.
The complete output of the Synchronous Meteorological Satellite was recorded on one inch magnetic tape. A quality control subsystem tests cloud track vectors against four sets of criteria: (1) rejection if best match occurs on correlation boundary; (2) rejection if major correlation peak is not distinct and significantly greater than secondary peak; (3) rejection if correlation is not persistent; and (4) rejection if acceleration is too great. A cloud height program determines cloud optical thickness from visible data and computer infrared emissivity. From infrared data and temperature profile, cloud height is determined. A functional description and electronic schematics of equipment are given.
Quality control measures for Ni-Cd spacecraft cells were analyzed. Cells were examined for electrolyte leakage, internal shorts, low capacity, or inability of any cell to recover its open circuit voltage above 1.50 volts during the internal short test. Test results are given in tabular form.
A compilation, containing articles on a number of analytical techniques for quality control engineers and laboratory workers, is presented. Data cover techniques for testing electronic, mechanical, and optical systems, nondestructive testing techniques, and gas analysis techniques.
Structural design considerations for O2 tank shells and suspension systems of ground based storage and mobile tank systems are outlined. Safety factors, chemical compatibility, liquid slosh strength, and cryogenic temperature properties are summarized. Finally, costs, quality control measures, and long life characteristics are examined.
Materials and design considerations are discussed for a low-cost, reliable radio-isotope-fueled thermoelectric generator for use in an undersea application. Plutonium has been selected as fuel, and the generator has to meet design goals of 2 watts after 20 years with a direct output voltage of 6-8 volts. The pressed and sintered form of Bi2Te3 appears to be the most appropriate thermoelectric material. Both fibrous and multilayer foil insulation could be used with proper processing and quality control, but there is less risk with fibrous type insulation. Min-K 1400 is recommended with a nitrogen cover gas. The heat source recommended is a three-layer capsule using T-111 for both the liner and strength member with an outer liner of Hastelloy-C.
Report discusses number of tests used in comparing polymer adhesives with metal bonding processes and includes charts and photographs to illustrate test results. Findings suggest reduced quality control costs when epoxies are used in fabrication of microcircuits.
Set of standards in the form of drawings provides detailed information about materials fastening techniques, surface finishes, critical dimensions, quality control specifications, and installation methods for variety of static and total pressure tube instrumentation.
Failure mechanisms, test techniques, and quality control procedures for difficult-to-detect class of failures have been devised. Test circuit provides electrostatic discharge similar to those encountered in production situation and assists in evaluation of susceptibility of specific circuits and devices
Strength ratios are reported which were derived from slow bend tests on 0.25 inch thick precracked Charpy specimens of steels, aluminum alloys, and a titanium alloy for which valid K sub Ic values were established. The strength ratios were used to develop calibration curves typical of those that could be useful in estimating K sub Ic for the purposes of alloy development of quality control.
Material specification and fabrication process procedures for foam production are presented. The properties of mechanical strength, modulus of elasticity, density and thermal conductivity were measured and related to foam quality. Properties unique to the foam such as a gas layer insulation, density gradient parallel to the fiber direction, and gas flow conductance in both directions were correlated with foam quality. Inspection and quality control tests procedures are outlined and photographs of test equipment and test specimens are shown.
The operational river basin snow mapping program at NESS is described with emphasis on quality control techniques and results for the 1974-1975 snow season.
The non spin platform is a means for achieving the very low acceleration requirements for cost effective space processing experiments on research rocket flights. These platforms have a low initial cost, are re-usable and have extremely low refurbishment cost. In order to attain this goal, commercially available components were used and only the necessary quality control standards were imposed. A detailed system description, the very few design problems encountered, the operational procedures (both pre-flight and post-flight), and the maintenance requirements are described.
APFO furnishes LANDSAT imagery and supporting NASA aircraft imagery to NASA-funded principal investigators who are working within the agriculture discipline. The office holds and reproduces Skylab imagery and a variety of aircraft photography (including infrared) from various government agencies. Available products are listed. Other topics discussed include quality control of photographic materials, analytical aerotriangulation, and photographic processes.
Management is a compilation of references to selected reports, journal articles, and other documents on the subject of management. This publication lists 368 documents originally announced in the 1975 issues of Scientific and Technical Aerospace Reports (STAR) or International Aerospace Abstracts (IAA). It includes references on the management of research and development, contracts, production, logistics, personnel, safety, reliability and quality control. It also includes references on: program, project and systems management; management policy, philosophy, tools, and techniques; decisionmaking processes for managers; technology assessment; management of urban problems; and information for managers on Federal resources, expenditures, financing, and budgeting.
The two dimensional static and dynamic current density distributions within the junction of semiconductor power switching devices and in particular the thyristors were obtained. A method for mapping the thermal profile of the device junctions with fine resolution using an infrared beam and measuring the attenuation through the device as a function of temperature were developed. The results obtained are useful in the design and quality control of high power semiconductor switching devices.
Data from routine ozone monitoring in southeastern Wisconsin and limited monitoring of the Milwaukee area by the Environmental Protection Agency are examined. Hourly averages as high as 30 pphm have been recorded in southeastern Wisconsin, and high readings have been reported in rural regions throughout the state. The observations indicate that photochemical oxidants and their nitrogen oxide and reactive hydrocarbon precursers advect from Chicago and northern Indiana into southeastern Wisconsin. There is evidence that synoptic-scale transport of photochemical oxidants occurs, allowing the pollution of entire anticyclones. These results cast doubt on the validity of the Air Quality Control Regions established by amendment to the Clean Air Act of 1970.