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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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Principles governing the photovoltaic effect in organic materials on the molecular level are studied and applied to the design and fabrication of laboratory devices having a photovoltaic organic polymer film as their key element. Progress to date has been in three areas: (1) materials synthesis; (2) apparatus development; and (3) ultra-thin film fabrication.
Assembly of custom-made electronic equipment and multipurpose commercial electronic equipment commonly found in electronics-development laboratories facilitates generation and modification of timing pattern signals for control of array detectors. Designed to serve as flexible electronic array-detector-testing apparatus configured via software; timing patterns created, stored, and changed easily. Assembly prepared for experimental evaluation of new detector design in much less time and less expense than necessary to construct special circuits to generate all timing patterns to be tried on new design.
Low temperature medium resolution measurements of the transmissivity of the ozone band have been made in the laboratory. The range of conditions under which the measurements were made are: -48 to -22 C, .0029 U .71 atmo.cm., 680 P 742 mmHg. The apparatus used is described briefly, measurement conditions are summarized and the resulting spectra are shown.
A concept and an apparatus designed to investigate the reflected and transmitted distributions of light from optically thick clouds is presented. The Cloud Field Optical Simulator (CFOS) is a laboratory device which utilizes an array of incandescent lamps as a source, simulated clouds made from cotton or styrofoam as targets, and an array of silicon photodiodes as detectors. The device allows virtually any source-target-detector geometry to be examined. Similitude between real clouds and their CFOS cotton or styrofoam counterparts is established by relying on a linear relationship between optical depth and the ratio of reflected to transmitted light for a semiinfinite layer. Comparisons of principal plane radiances observed by the CFOS with Monte Carlo computations for a water cloud at 0.7 micron show excellent agreement. Initial applications of the CFOS are discussed.
A concept and an apparatus designed to investigate the reflected and transmitted distributions of light from optically thick clouds is presented. The Cloud Field Optical Simulator (CFOS) is a laboratory device which utilizes an array of incandescent lamps as a source, simulated clouds made from cotton or styrofoam as targets, and an array of silicon photodiodes as detectors. The device allows virtually any source-target-detector geometry to be examined. Similitude between real clouds and their CFOS cotton or styrofoam counterparts is established by relying on a linear relationship between optical depth and the ratio of reflected to transmitted light for a semi-infinite layer. Comparisons of principal plane radiances observed by the CFOS with Monte Carlo computations for a water cloud at 0.7 microns show excellent agreement.
Direct measurements were undertaken at the Aeronautics Laboratory in Turin of the aerodynamic actions on an oscillating wing. The tests conducted had as their essential object the examination of the operation of apparatus designed for this measurement. The values experimentally obtained for the aerodynamic coefficients are in good agreement with the theory of oscillatory motion of the wing of finite span and show clear deviation from the values obtained by theory of plane motion.
Veterans Administration medical researchers, along with Langley Research Center are investigating possibility that peritoneal membrane (lining of abdominal cavity) can absorb nutrients and thus provide alternative route for nutrition when intestinal function is impaired. Apparatus (cake box design) consists of octagonal chamber with eight smaller chambers attached and secured by O-ring seals. Design is simple, interchangeable, and time controllable.
A mission model which will accommodate commercial users and provide a basic data base for further mission planning is reported. The data bases to be developed are: (1) user requirements; (2) apparatus capabilities and availabilities; and (3) carrier capabilities. These data bases are synthesized in a trades and analysis phase along with the STS flight apparatus, and optimum missions will be identified. The completed work is reported. The user requirements data base was expanded to identify within the six scientific disciplines the areas of investigation, investigation categories and status, potential commercial application, interested parties, process, and experiment requirements. The scope of the apparatus data base was expanded to indicate apparatus status as to whether it is ground or flight equipment and, within both categories, whether the apparatus is: (1) existing, (2) under development, (3) planned, or (4) needed. Applications for the apparatus are listed. The methodology is revised in the areas of trades and analysis and mission planning. The carrier capabilities data base was updated and completed.
The Impact Dynamics Laboratory at NASA Glenn Research Center recently developed a pneumatically-actuated crash sled for investigating the crush behavior of structural elements for vehicular applications. The apparatus includes an adjustable striker mass and specimen support mass, which are mounted on separate rails. This setup provides two advantages over crash sleds with so-called fixed specimen supports: (i) it allows for multiple independent measurements of the crush response using different instruments, and (ii) the specimen support can be varied and its reaction can be explicitly measured. This paper describes the experimental setup and data analysis methodology and illustrates the capability of the sled for measuring the specific energy absorption (SEA) of triaxially-braided carbon/epoxy composite C-channels and corrugated plates. The corrugated plate had a higher SEA than the C-channel and the SEAs did not vary when the striker mass and velocity were changed so that incident energy was constant.
The Impact Dynamics Laboratory at NASA Glenn Research Center recently developed a pneumatically-actuated crash sled for investigating the crush behavior of structural elements for vehicular applications. The apparatus includes an adjustable striker mass and specimen support mass, which are mounted on separate rails. This setup provides two advantages over crash sleds with so-called fixed specimen supports: (i) it allows for multiple independent measurements of the crush response using different instruments, and (ii) the specimen support can be varied and its reaction can be explicitly measured. This paper describes the experimental setup and data analysis methodology and illustrates the capability of the sled for measuring the specific energy absorption (SEA) of triaxially-braided carbon/epoxy composite C-channels and corrugated plates. The corrugated plate had a higher SEA than the C-channel and the SEAs did not vary when the striker mass and velocity were changed so that incident energy was constant.
The Impact Dynamics Laboratory at NASA Glenn Research Center recently developed a pneumatically-actuated crash sled for investigating the crush behavior of structural elements for vehicular applications. The apparatus includes an adjustable striker mass and specimen support mass, which are mounted on separate rails. This setup provides two advantages over crash sleds with so-called fixed specimen supports: (i) it allows for multiple independent measurements of the crush response using different instruments, and (ii) the specimen support can be varied and its reaction can be explicitly measured. This paper describes the experimental setup and data analysis methodology and illustrates the capability of the sled for measuring the specific energy absorption (SEA) of triaxially-braided carbon/epoxy composite C-channels and corrugated plates. The corrugated plate had a higher SEA than the C-channel and the SEAs did not vary when the striker mass and velocity were changed so that incident energy was constant.
Mechanical, optical, and operating properties of an experiment chamber are examined and possible sample contamination difficulty is explained. The mechanical and operational characteristics of this apparatus are well suited for the study of the reflectance spectra of frosts. The infrared energy available at the detector is low and steps to increase the energy and the responsivity of the detector were taken. The problem of a standard diffuse reflector which is useful in the far ultraviolet region is considered and it is suggested that bright gold be used as the standard.
A motion sickness device is described which produces motion sickness in about 40 percent of an unselected population of unrestrained female cats during a 30-min exposure at 0.28 Hz. The apparatus provides a gentle wave stimulus, similar to that provided by an amusement park Ferris Wheel. Two cats may be tested at the same time. This device is useful for studies of putative antimotion sickness drugs or the biochemical basis of the emetic response to motion.
The recommendations, procedures, and techniques are summarized which provided by the Kodak Apparatus Division to the Ames Research Center to support the Earth Resources Aircraft Program at that facility. Recommendations, procedures, and calibration data are included for sensitometry, densitometry, laboratory cleanliness, and determination of camera exposure. Additional comments are made regarding process control procedures and general laboratory operations.
We describe our ongoing program to measure velocity dependent charge transfer (CT) cross sections for selected ions on atomic hydrogen using the ion-aloin merged-beams apparatus at Oak Ridge Natioiial Laboralory. Our focus is on those ions for which CT plays an important role in determining the ionization structure, line emis sion, and thermal structure of observed cosmic photoionized plasmas.
Thermal performance measurement of piping systems under actual field conditions is important for space launch development and commercial industry. Knowledge of the true insulating effectiveness is needed in system design, development, and research activities. A new 18-meter-long test apparatus for cryogenic pipelines has been developed. Three different pipelines, rigid or flexible, can be tested simultaneously. Critical factors in heat leak measurements include eliminating heat transfer at end connections and obtaining proper liquid saturation condition. Effects due to variations in the external ambient conditions like wind, humidity, and solar radiation must be minimized. The static method of liquid nitrogen evaporation has been demonstrated, but the apparatus can be adapted for dynamic testing with cryogens, chilled water, or other working fluids. This technology is suited for the development of an industry standard test apparatus and method. Examples of the heat transfer data from testing commercially available pipelines are given. Prototype pipelines are currently being tested and evaluated at the Cryogenics Test Laboratory of NASA Kennedy Space Center.
It is well known that fires in the low-gravity environment of Earth-orbiting spacecraft are different from fires on Earth. The flames lack the familiar upward plume, which is the result of gravitational buoyancy. These flames, however, are strongly influenced by minor airflow currents. A recent study conducted in low gravity (microgravity) on the Russian orbital station Mir used burning plastic rods mounted in a small chamber with a controllable fan to expose the flame to airflows of different velocities. In this unique project, a Russian scientific agency, the Keldysh Research Center, furnished the apparatus and directed the Mir tests, while the NASA Glenn Research Center at Lewis Field provided the test materials and the project management. Reference testing and calibrations in ground laboratories were conducted jointly by researchers at Keldysh and at the NASA Johnson Space Center's White Sands Test Facility. Multiple samples of three different plastics were burned in the tests: Delrin, a common material for valve bodies; PMMA, a plastic "glass"; and polyethylene, a familiar material for containers and films. Each burned with a unique spherical or egg-shaped flame that spread over the rod. The effect of varying the airflow was dramatic. At the highest airflow attainable in the combustion chamber, nearly 10 cm/sec (a typical ventilation breeze), the flames were bright and strong. As airflow velocity decreased, the flames became shorter but wider. In addition, the flames became less bright, and for PMMA and polyethylene, they showed two colors, a bright part decreasing in volume and a nearly invisible remainder (see the photographs). Finally, at a very low velocity, the flames extinguished. For the plastics tested, this minimum velocity was very low, around 0.3 to 0.5 cm/sec. This finding confirms that at least a slight airflow is required to maintain a flame in microgravity for these types of materials.
Because salt and metals can mask the signature of a variety of organic molecules (like amino acids) in any given sample, an automated system to purify complex field samples has been created for the analytical techniques of electrospray ionization/ mass spectroscopy (ESI/MS), capillary electrophoresis (CE), and biological assays where unique identification requires at least some processing of complex samples. This development allows for automated sample preparation in the laboratory and analysis of complex samples in the field with multiple types of analytical instruments. Rather than using tedious, exacting protocols for desalting samples by hand, this innovation, called the Automated Sample Processing System (ASPS), takes analytes that have been extracted through high-temperature solvent extraction and introduces them into the desalting column. After 20 minutes, the eluent is produced. This clear liquid can then be directly analyzed by the techniques listed above. The current apparatus including the computer and power supplies is sturdy, has an approximate mass of 10 kg, and a volume of about 20 20 20 cm, and is undergoing further miniaturization. This system currently targets amino acids. For these molecules, a slurry of 1 g cation exchange resin in deionized water is packed into a column of the apparatus. Initial generation of the resin is done by flowing sequentially 2.3 bed volumes of 2N NaOH and 2N HCl (1 mL each) to rinse the resin, followed by .5 mL of deionized water. This makes the pH of the resin near neutral, and eliminates cross sample contamination. Afterward, 2.3 mL of extracted sample is then loaded into the column onto the top of the resin bed. Because the column is packed tightly, the sample can be applied without disturbing the resin bed. This is a vital step needed to ensure that the analytes adhere to the resin. After the sample is drained, oxalic acid (1 mL, pH 1.6-1.8, adjusted with NH4OH) is pumped into the column. Oxalic acid works as a chelating reagent to bring out metal ions, such as calcium and iron, which would otherwise interfere with amino acid analysis. After oxalic acid, 1 mL 0.01 N HCl and 1 mL deionized water is used to sequentially rinse the resin. Finally, the amino acids attached to the resin, and the analytes are eluted using 2.5 M NH4OH (1 mL), and the NH4OH eluent is collected in a vial for analysis.