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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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At least 1,009 records · Page 56
All sourcesNASA NTRSDOE OSTI
NASA NTRS1981

Solar-site test module

Report describes small test set which interrogates solar-energy data acquisition systems. Lightweight, portable set includes microcomputer with keyboard, alphanumeric display, printer, cassette recorder/player for storing programs and data, and cable for connection to Site Data Acquisition System (SDAS). Unit is operated by BASIC program and Assembly language. Report is specific to DOE/NASA application yet contains general information to assist in designing similar units.

Kissel, R. R.↗
NASA NTRS1981

Penumatic-power supply

Portable compressed air supply has two or more outputs at pressures from 20 to 100 psi. Applications include operating production equipment, spraying paint and lubricants, and pressurizing refrigeration systems. Supply filters air from standard high-pressure line, reduces it to working pressure, and adds lubricant when required. Regulator supplies low-pressure air to output channels. On channel lines, vernier-control valves select output pressures.

Kramer, R. C.↗
NASA NTRS1978

Airborne measurements of cloud forming nuclei and aerosol particles at Kennedy Space Center, Florida

Results of airborne measurements of the sizes and concentrations of aerosol particles, ice nuclei, and cloud condensation nuclei that were taken at Kennedy Space Center, Florida, are presented along with a detailed description of the instrumentation and measuring capabilities of the University of Washington airborne measuring facility (Douglas B-23). Airborne measurements made at Ft. Collins, Colorado, and Little Rock, Arkansas, during the ferry of the B-23 are presented. The particle concentrations differed significantly between the clean air over Ft. Collins and the hazy air over Little Rock and Kennedy Space Center. The concentrations of cloud condensation nuclei over Kennedy Space Center were typical of polluted eastern seaboard air. Three different instruments were used to measure ice nuclei: one used filters to collect the particles, and the others used optical and acoustical methods to detect ice crystals grown in portable cloud chambers. A comparison of the ice nucleus counts, which are in good agreement, is presented.

Radke, L. F.↗
NASA NTRS1978

The Lixiscope concept

A portable X-ray imagery instrument which utilizes a converter phosphor or scintillator to convert the X-ray image into visible light image is described. The potential medical as well as industrial applications of the Lixiscope are presented.

Yin, L. I.↗
NASA NTRS1978

Orthopedic evaluation

The clinical performance of the Lixiscope in orthopedics was compared with routine radiography. Portability and size were the major advantages of the Lixiscope. The main disadvantage at this point in time was the Lixiscope's inability to study large areas.

Walden, T.↗
NASA NTRS1980

Manufacturing process applications team (MATeam)

The objectives and activities of an aerospace technology transfer group are outlined and programs in various stages of progress are described including the orbital tube flaring device, infrared proximity sensor for robot positioning, laser stripping magnet wire, infrared imaging as welding process tracking system, carbide coating of cutting tools, nondestructive fracture toughness testing of titanium welds, portable solar system for agricultural applications, and an anerobic methane gas generator.

Bangs, E. R.↗
NASA NTRS1979

Induced electric currents in the Alaska oil pipeline measured by gradient, fluxgate, and SQUID magnetometers

The field gradient method for observing the electric currents in the Alaska pipeline provided consistent values for both the fluxgate and SQUID method of observation. These currents were linearly related to the regularly measured electric and magnetic field changes. Determinations of pipeline current were consistent with values obtained by a direct connection, current shunt technique at a pipeline site about 9.6 km away. The gradient method has the distinct advantage of portability and buried- pipe capability. Field gradients due to the pipe magnetization, geological features, or ionospheric source currents do not seem to contribute a measurable error to such pipe current determination. The SQUID gradiometer is inherently sensitive enough to detect very small currents in a linear conductor at 10 meters, or conversely, to detect small currents of one amphere or more at relatively great distances. It is fairly straightforward to achieve imbalance less than one part in ten thousand, and with extreme care, one part in one million or better.

Campbell, W. H.↗
NASA NTRS1980

Wireless microphone communication system telephonics P/N 484D000-1

The wireless microphone is a lightweight, portable, wireless voice communications device for use by the crew of the space shuttle orbiter. The wireless microphone allows the crew to have normal hands-free voice communication while they are performing various mission activities. The unit is designed to transmit at 455 or 500 kilohertz and employs narrow band FM modulation. Two orthogonally placed antennas are used to insure good reception at the receiver.

Source record↗
NASA NTRS1980

The GSFC Mark-2 three band hand-held radiometer

A self-contained, portable, hand-radiometer designed for field usage was constructed and tested. The device, consisting of a hand-held probe containing three sensors and a strap supported electronic module, weighs 4 1/2 kilograms. It is powered by flashlight and transistor radio batteries, utilizes two silicon and one lead sulfide detectors, has three liquid crystal displays, sample and hold radiometric sampling, and its spectral configuration corresponds to LANDSAT-D's thematic mapper bands. The device was designed to support thematic mapper ground-truth data collection efforts and to facilitate 'in situ' ground-based remote sensing studies of natural materials. Prototype instruments were extensively tested under laboratory and field conditions with excellent results.

Tucker, C. J.↗
NASA NTRS1980

Backpack VLBI terminal with subscentimeter capability

Backpack portable equipment was developed to measure vector baseline from approximately 1 km to 100 km in length with subcentimeter to few centimeter accuracy. The equipment design features as well as the instrumentation specifications are discussed. It is shown that the unit has the following advantages: it is simple in concept; it is reliable in unattended operation; and it is inexpensive (less than $15,000 per unit).

Connselman, C. C., III↗
NASA NTRS1979

Time dissemination: An update

A brief description of some of the improvements in the generation and dissemination of precise time and time interval at the U.S. Naval Observation are described. Details on some of the newer hardware developed for this purpose are presented. Data from tests of two of the more significant items, a small portable clock with performance approaching that of larger units and a GPS Time Transfer Unit capable of time transfer to an accuracy of less than 100 nanoseconds, are also given.

Putkovich, K.↗
NASA NTRS1979

T and F comparisons via broadcasting satellite and navigation technology satellite

The preliminary time/frequency dissemination experiments were made using the BSE. In order to establish the technique of the doppler shift canceling, the phase control servo including the satellite link and the precompensating frequency control using the measured values or using the orbital data of the satellite are tested. The amount of the residual doppler shift at the control station can be reduced to the order of 1 part in 10 to the 12th power or less by use of the first and the second methods. The method using the orbit data is expected to give a control capability of a few parts in 10 to 11th power. Thus, the maximum value of the doppler shift at the farther most place of the country is estimated to be + or - 2 x 10 to the -10 power without any correction. The experiment of the international time comparison via the NTS 1 was made for about one year since October 1978. The data of time difference between UTC(USNO) and UTC(RRL) are in good agreement with those via the portable clock of the USNO. By applying the correction for ionospheric delay the standard deviation of the data can be reduced to about one-half.

Saburi, Y.↗
NASA NTRS1979

The frequency and time standard and activities at the Beijing Institute of Radio Metrology and Measurements

Three kinds of frequency measuring systems are described: frequency comparison, phase comparison, and time comparison. With the help of the portable cesium clock in determining the time delay between two stations, a time synchronization, experiment was conducted using the Symphonie satellite. A result with an accuracy of 30 ns and an uncertainty of about 10 ns was obtained. Another experiment, applying the television pulse technique for time synchronization, yielded a result with an error of about 0.5 mu s in 24 hours. In order to measure the short term frequency stability of crystal oscillators or other frequency sources, a rubidium maser atomic frequency standard was developed as well as a short term stability measuring system.

Wang, H. T.↗
NASA NTRS1979

Making real-time sun reflectance measurements with a microprocessor-based spectroradiometer

A standard high-speed, field-portable spectroradiometric measurement system built around a programmable microprocessor has been adapted to the form of a Reflectometer/Comparator. In this configuration, the instrument makes passive measurements of the absolute reflectance of agricultural plant canopies over a spectral range of 0.4 to 2.5 micrometers. Real-time absolute measurements are made possible by an optical chopper which constantly compares the target with the sun, and makes extensive measurements of solar reflectance from a variety of these targets. The paper describes the instrumentation and measurement procedures, reviews the software programming and discusses the results.

Zweibaum, F. M.↗
NASA NTRS1979

A gas chromatographic air analyzer fabricated on a silicon wafer

A miniature gas analysis system has been built based on the principles of gas chromatography (GC). The major components are fabricated in silicon using photolithography and chemical etching techniques, which allows size reductions of nearly three orders of magnitude compared to conventional laboratory instruments. The chromatography system consists of a sample injection valve and a 1.5-m-long separating capillary column, which are fabricated on a substrate silicon wafer. The output thermal conductivity detector is separately batch fabricated and integrably mounted on the substrate wafer. The theory of gas chromatography has been used to optimize the performance of the sensor so that separations of gaseous hydrocarbon mixtures are performed in less than 10 s. The system is expected to find application in the areas of portable ambient air quality monitors, implanted biological experiments, and planetary probes.

Terry, S. C.↗
NASA NTRS1980

Observations of interstellar H2O emission at 183 gigahertz

Observations of the 183-GHz rotational transition of water vapor in interstellar molecular clouds are reported. The observations were made with a portable double-sideband superheterodyne radiometer used with the 91-cm Cassegrain telescope on board the Kuiper Airborne Observatory. An emission feature was detected in the direction of the Kleinmann-Low nebula in Orion with a peak antenna temperature of 15 K, a local standard of rest velocity of 8 km/sec, and a width of 15 km/sec. A plateau component of the emission profile is attributed to the 1-arcmin region characteristic of plateau emission from other observed molecules, with emission enhanced over that expected for thermal excitation, while the spike component observed is consistent with an optically thick source of the size of the molecular ridge in Orion at a temperature of 50 K and a column density greater than or equal to 3 x 10 to the 17th/sq cm, implying that H2O is one of the more abundant species in the Orion Molecular Cloud. Emission at 183 GHz was not detected in Sgr A, Sgr B2, W3, W43, W49, W51, DR 21, NGC 1333, NGC 7027, GL 2591 or the Rho Oph cloud; it may have been detected in M 17.

Waters, J. W.↗
NASA NTRS1979

Storage, transmission and distribution of hydrogen

Current practices and future requirements for the storage, transmission and distribution of hydrogen are reviewed in order to identify inadequacies to be corrected before hydrogen can achieve its full potential as a substitute for fossil fuels. Consideration is given to the storage of hydrogen in underground solution-mined salt caverns, portable high-pressure containers and dewars, pressure vessels and aquifers and as metal hydrides, hydrogen transmission in evacuated double-walled insulated containers and by pipeline, and distribution by truck and internal distribution networks. Areas for the improvement of these techniques are indicated, and these technological deficiencies, including materials development, low-cost storage and transmission methods, low-cost, long-life metal hydrides and novel methods for hydrogen storage, are presented as challenges for research and development.

Kelley, J. H.↗