The electron microprobe for chemical analysis
Electron microprobe for X-ray fluorescence chemical analysis
X-RAY FLUORESCENCE↗
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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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Observations of the solar particle event of 5 to 12 February 1965 with Mariner IV AND Injun IV
Solar energetic particle intensities obtained with Mariner IV and Injun IV during 5-12 February 1965 cosmic ray event
SOLAR RADIO BURST↗
Impurity distribution in MgO.
Microprobe study of impurities in hot-pressed polycrystalline MgO compact and existence of significant grain boundary volume
IMPURITY↗
The electron microprobe X-ray analyzer and its application in mineralogy.
Monograph on electron microprobe X-ray analyzer and application in mineralogy
MINERALOGY↗
Electron Microprobe Analyses of Powders Darkened by Simulated Solar-Wind Irradiation
Electron microprobe analysis of quartz and alumina darkening upon solar wind ion bombardment, noting existence of iron, tungsten and carbon in samples
SOLAR WIND↗
Hypersonic turbulent boundary layer measurements using an electron beam Final report, Oct. 1966 - May 1968
Direct measurement of density in turbulent boundary layer on shock tunnel nozzle wall using electron beam probe
Wallace, J. E.↗
Hypersonic turbulent boundary-layer measurements using an electron beam.
Density and density fluctuations in hypersonic turbulent boundary layer on shock tunnel nozzle wall measured using electron beam probe
Wallace, J. E.↗
X-ray probe, SEM, and optical property analysis of the surface features of Surveyor III materials
X ray probe, scanning electron microscopy and spectral reflectance analysis of lunar environment effects on Apollo 12 returned Surveyor 3 materials surface cratering
Anderson, D. L.↗
Low-cost clearance indicator for high speed turbomachinery
System consists of hermetically sealed capacitance probe, compact electronic driver, power supply, and oscilloscope and/or voltmeter for readout. System requires no mechanical connection to the rotating parts of turbomachinery, and does not disrupt rotor mainstream flow pattern. It can be effectively used in other applications to measure dynamic clearances between moving and stationary parts.
Evans, R. C.↗
Magnetic control assembly reports
Results are summarized of the qualification level vibration tests performed on the magnet control assembly (MCA) for Nimbus and ERTS satellites. The MCA electronics and probe units have demonstrated the capability to survive qualification sinusoidal and random vibration levels. The functional testing indicated normal operation of the units after each axis of vibration. Visual inspection indicated no evidence of degradation. Post vibration acceptance testing verified normal operation of the MCA.
Stickler, A. C.↗
Airborne particle monitoring by electrostatic precipitation
For qualitative analysis of atmospheric particulates by microscopy, the sampling device should preserve the particles in the state existing at the moment of capture. A collector is described that uses electrostatic precipitation to capture and disperse specimens on various substrates for direct insertion into microscopes. Sampling runs in various atmospheres are described. Micrographs are presented to show particle morphology and distribution on the substrates. Chemical identification by X-ray energy probe and electron diffraction is illustrated.
Robinson, J. C.↗
IECM calibration and data reduction requirements
The induced environment contamination monitor (IECM) tape recorder format, as it relates to the ouput of meaningful data from the IECM instrument, is explained. Eight-bit words (or bytes) generate numbers that represent voltage levels of electronic detection probes for each experiment. This information is amalgamated by the IECM Data Acquisition and Control System (DACS). In some cases bits represent certain status situations concerning an experiment, such as whether a valve is opened or closed. Voltages are transformed into meaningful physical phenomena through equations of calibration. Data formats and plots are generated as requested for each IECM experimenter.
Wills, F. D.↗
Plasma double-layers produced by ponderomotive force
Non-linear rectification of the RF electric fields excited in a convectively amplifying electron beam-plasma interaction results in a dc electric field, and a corresponding ponderomotive force acting on the charged particles to produce a space-charge separation, i.e. a type of plasma double-layer. This paper analyses the effect, taking into account plasma electron temperature and electron-neutral collisions. To measure such double-layers, an electron beam probe constitutes a convenient non-perturbing diagnostic technique, but great care is required in its calibration. An analysis is presented taking into account significant non-linear effects which had been neglected in previous work. The paper concludes with some preliminary experimental results illustrating the use of the technique in a beam-plasma interaction for which a weak double-layer electric field is predicted.
Levine, J. S.↗
Dynamical response of the dayside ionosphere of Venus to the solar wind
Dayside ion composition measurements made by the orbiter ion mass spectrometer and the orbiter electron temperature probe on the Pioneer Venus orbiter are used to infer the dominant processes involved in the dynamic response of the Venus ionosphere to the solar wind. The analysis is confined to the topside ionosphere in the vicinity of the subsolar point, where the ionosphere-solar wind interaction is expected to be maximized. Height profiles of the ion composition and plasma temperatures in the main body of the topside ionosphere, lying between the ionopause and chemical equilibrium regions, reveal that the ionosphere is in a compressed state. This region of the ionosphere is interpreted in terms of a stationary equilibrium where the compression is derived from the ponderomotive force j x B. The estimated magnitude of this force is confirmed by the magnetic field measurements made by the orbiter magnetometer.
Hartle, R. E.↗
The Venus ionosphere as an obstacle to the solar wind
Pioneer Venus Orbiter Electron Temperature Probe measurements of hundreds of bow shock and ionopause crossings are employed in describing the configuration of these two boundaries and their variations in response to changes in solar wind pressure. The average bow shock configuration is found to be well represented by an Archimedian hyperboloid whose altitude at the subsolar point is 0.46 Venus radii, a value slightly greater than that derived from Pioneer Venus magnetometer data using a fit to a general conic section. It is noted that the average bow shock configuration exhibits a high degree of azimuthal symmetry near the terminator. The orbit to orbit variability of the shock location is unexpectedly large, the standard deviation being about 10%. A tendency is noted for the bow shock and the ionopause to expand and contract simultaneously, but the weakness of their orbit by orbit correlation suggests that the ionopause of Venus is not the only obstacle to the solar wind. It is thought that such processes as photoion pickup and charge exchange with neutrals may be important in diverting the solar wind plasma around the planet.
Theis, R. F.↗
Probing the magnetsophere with artificial electron beams
An analysis is conducted of the University of Minnesota Electron Echo experiments, which so far have included five sounding rocket experiments. The concept of the Echo experiment is to inject electron beam pulses from a rocket into the ionosphere at altitudes in the range from 100 to 300 km. The electrons move to the conjugate hemisphere following magnetic field lines and return on neighboring field lines to the neighborhood of the rocket where the pulses may be detected and analyzed. Attention is given to the detection and analysis of echoes, the structure of echoes, and the Echo V experiment. The Echo V experiment showed clearly that detection of remote echo beams by atmospheric fluorescence using low light level TV system is not a viable technique. A future experiment is to use throw-away detectors for direct remote echo detection.
Winckler, J. R.↗
Observations of energetic ions near the Venus ionopause
Ions (primarily O/+/) with spacecraft rest frame energies greater than 40 eV have been observed by the Pioneer Venus Neutral Mass Spectrometer. The signature occurs in about 13% of the 700 orbits examined, primarily near the ionopause and at all solar zenith angles. The energetic ions coincide in location with superthermal ions observed by the Ion Mass Spectrometer and more rarely occur in some of the plasma clouds observed by the Electron Temperature Probe. These observations in conjunction with measurements by the Plasma Wave Instrument near the ionopause suggest that the ions are accelerated out of ionospheric plasma by the shocked solar wind through plasma wave-particle interactions.
Kasprzak, W. T.↗
Vacuum Seal Permits Limited Rotation
Flexible metal seal permits rotation of object in vacuum chamber. Seal made from two cylindrical azimuthally fluted bellows attached to ends of cylindrical axially fluted bellows with connecting tubes at both ends. Designed for rotation of sample probes in electron spectroscopy for chemical analysis (ESCA), other applications likely.
Lombardi, F.↗