Stress corrosion susceptibility of titanium alloys in aqueous environment.
Stress corrosion cracking of alpha and alpha-beta Ti alloys in aqueous environment at ambient temperature, noting Al content and microconstituents
Mackay, T. L.↗
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Results for “ambient temperature”
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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Differential pressure cell Patent
Differential pressure cell insensitive to changes in ambient temperature and extreme overload
Dimeff, J.↗
Cold exposure and intestinal absorption in the hamster
Low ambient temperature exposure effect on hamster intestinal absorption capacity, using glucose test compound
Barr, R. E.↗
Fluid balance in artificial environments - Role of environmental variables
Human fluid balance in artificial environments, and influence of ambient temperature, water vapor pressure, total barametric pressure, wind velocity, and atmospheric gas composition
Carleton, W. M.↗
Correlation of creep elongation and substructure in aluminum-stainless steel composites
Al matrix-stainless steel composites under tensile loading parallel to reinforcement direction, noting creep behavior at ambient temperature
Lawley, A.↗
Improved ohmic contacts to n-type GaP devices
Metal film ohmic contacts to n-type GaP devices operating at high ambient temperatures
Domenico, A. J.↗
Fuel droplet burning rates in a combustion gas environment
Fuel droplet burning rate variation with ambient temperature and oxygen concentration in combustion gas environment
Faeth, G. M.↗
Quick, easy to prepare freeze-dried soups
Major advantages of soups are that they totally rehydrate in less than five minutes in water at approximately 150 deg F, maintain flavor and quality stability for two weeks in a 100 F environment, and remain stable for considerably longer at ambient temperatures. They are suitable for either household or field use.
Ramirez, R. V.↗
Simple gas chromatographic system for analysis of microbial respiratory gases
Dual column ambient temperature system, consisting of pair of capillary columns, microbead thermistor detector and micro gas-sampling valve, is used in remote life-detection equipment for space experiments. Performance outweighs advantage gained by utilizing single-column systems to reduce weight, conserve carrier gas and operate at lower power levels.
Carle, G. C.↗
Evaluation program for secondary spacecraft cells: Acceptance test of McDonnell-Douglas, Astropower division, 40.0 ampere hour silver-zinc cells
The development of an inorganic separator material for use in construction of 40 ampere-hour silver zinc cells is discussed. Acceptance tests were conducted to determine real quality, physical defects and ampere-hour capacity. All acceptance tests were performed at an ambient temperature of 23 to 27 C at existing relative humidity and atmospheric pressure. Of the 63 cells tested, only one failed to meet the equipment specifications.
Harkness, J. D.↗
A study of LC-39 cryogenic systems. Part 1: A study of the vacuum insulated transfer lines at Kennedy Space Center. Part 2: Cooldown pressure surges
The vacuum liquid hydrogen and liquid oxygen transfer lines at Kennedy Space Center were studied to evaluate the feasibility of using a condensing gas such as CO2 inside the vacuum spaces to achieve a condensing-vacuum. The study indicates that at ambient temperature, a maximum vacuum hyphen space pressure of 4000 microns is acceptable for the LH2 transfer lines. In addition, the cooldown procedures for the 14-inch cross-country liquid oxygen line was studied using a simplified mathematical model. Preliminary cooldown times are presented for various heat leak rates to the line and for two vent configurations.
Ludtke, P. R.↗
Flammability testing conducted in support of Apollo 13
In support of the Apollo 13 investigation of the oxygen tank failure, flame propagation rates were determined for Teflon insulation in cryogenic and ambient temperature oxygen for upward, downward, and zero g burns. The propagation rates depended heavily on configuration and varied from 4.8 to 10.9 cm/sec for upward one g burns to 0.48 cm/sec for zero g burns. In addition to the flame propagation rates, tests were conducted to determine if Teflon burning in cryogenic oxygen could ignite metals (promoted ignition) with which it came in contact. Tests conducted on various metal alloys used in the oxygen tank indicated that most of the alloys could be ignited by burning Teflon in certain configurations. After the propagation rates and promoted metal ignitions had been evaluated, a test was conducted on a quantity gauge and wire harness used in the oxygen tank to determine if flame propagation to the tank wall was possible. Propagation of the wire bundle after ignition resulted in a catastrophic failure of the test vessel in the area of the quantity gauge.
Leger, L. J.↗
NASA-ARC 36 inch airborne infrared telescope
A 36 in. aperture telescope is being developed for installation aboard a NASA-Lockheed C-141A aircraft. This airborne observatory will permit observation of infrared emission at altitudes above 45,000 ft above much of the infrared-absorbing atmospheric water vapor. The telescope will look through a movable open port in the aircraft fuselage. A porous spoiler, upstream from the open port, will attenuate pressure disturbances and permit operation at ambient temperatures and pressures without an obscuring window. The telescope's entire structure is supported by a 16 in. spherical air bearing, which effectively isolates it from angular aircraft motions. This air bearing support, with inertial stabilization and star tracking, will permit net line of sight stability of better than 2 arcsec rms.
Mobley, R. E.↗
Navy-developed life support systems for fully enclosed protective suits
The development and performance of an environmental control unit capable of supporting a man in an impermeable suit at ambient temperatures up to 140 F for periods of up to two hrs is reported. The basic suit operation consists of cooling by wet ice contained in a suitcase. The system is designed to circulate and cool the air within the suit, to remove excess moisture and carbon dioxide, and to maintain a safe oxygen level.
Orner, G. M.↗
Comparative lubrication studies of OH-58A tail rotor drive shaft bearings
Comparative lubrication tests were run with OH-58A helicopter tail rotor drive shaft bearings. The tests were run in an outdoor environment with ambient temperatures ranging from 10 to 75 F. Dust was periodically applied to the bearings to simulate field conditions. The cause of bearing failure was associated with dust penetration. Rotor shaft failure was found to be caused by the shaft rotating in the standard rubber collar due to seizure of the bearings. Bearings with a positive rubbing seal having a MIL-G-81322 grease produced lives greater than with bearings having labyrinth seals and a mineral oil paste lubricant. An elongated collar prevented failure of the rotor shaft during bearing seizure. In a limited test, installation of tail boom shrouds over the bearings which excluded dust and water resulted in bearing lives in excess of 1800 hours or 1200 hours greater than the current 600 hours TBO, regardless of the lubricant-bearing combination used.
Dietrich, M. W.↗
High intensity portable fluorescent light
Eight high intensity portable fluorescent lights were produced. Three prototype lights were also produced, two of which were subsequently updated to the physical and operational configuration of the qualification and flight units. Positioning of lamp apertures and reflectors in these lights is such that the light is concentrated and intensified in a specific pattern rather than widely diffused. Indium amalgam control of mercury vapor pressure in the lamp gives high output at lamp ambient temperatures up to 105 C. A small amount of amalgam applied to each electrode stem helps to obtain fast warm-up. Shrinking a Teflon sleeve on the tube and potting metal caps on each end of the lamp minimizes dispersion of mercury vapor and glass particles in the event of accidental lamp breakage. Operation at 20 kHz allows the lamps to consume more power than at low frequency, thus increasing their light output and raising their efficiency. When used to expose color photographic film, light from the lamps produces results approximately equal to sunlight.
Kendall, F. B.↗
Long-term storage test of a Syncom solid rocket motor
After 7.5 years of storage at ambient temperature, a solid propellant apogee motor was tested successfully. The performance of the motor did not deteriorate as a result of prolonged storage. Tabular performance data and graphic thrust and pressure variations are given.
Ray, R. L.↗
A predictive model of human performance.
An attempt is made to develop a model describing the overall responses of humans to exercise and environmental stresses for prediction of exhaustion vs an individual's physical characteristics. The principal components of the model are a steady state description of circulation and a dynamic description of thermal regulation. The circulatory portion of the system accepts changes in work load and oxygen pressure, while the thermal portion is influenced by external factors of ambient temperature, humidity and air movement, affecting skin blood flow. The operation of the model is discussed and its structural details are given.
Walters, R. F.↗