Terrestrial variational tables for the periods and attenuation of the free oscillations.
Terrestrial free oscillation periods and attenuation variations related to physical parameters for checking earth models
Wiggins, R. A.↗
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Gaseous hydrogen requirements for the discharge of liquid hydrogen from a 1.52 meter /5 ft/ diameter spherical tank
Physical parameter effect on pressurant gas requirements during expulsion of liquid hydrogen from spherical tanks
Dewitt, R. L.↗
Limit cycle oscillations in pulse-modulated systems.
Two-pulse limit cycle oscillation stability relation to physical parameters of pulse modulated feedback system used for satellite attitude control
Clark, R. N.↗
Limit cycle oscillations in pulse-modulated systems.
Pulse modulated feedback system for satellite attitude control, analyzing relationship between physical parameters to ensure two pulse limit cycle oscillation stability
Clark, R. N.↗
Study of the audibility of impulsive sounds
Anechoic chamber investigation of physical parameter effects on perceived noisiness of impulsive signals
Fidell, S.↗
OGO-3 dust particle experiment - Data reduction and analysis Final report
OGO 3 experiment to measure physical parameters of picogram size dust particles in cislunar and near earth space
Bohn, J. L.↗
The problem of uniqueness in thermosphere dynamics
The unique solution of tidal wave propagation within the thermosphere depends on the boundary conditions of the model. It is shown that the radiation condition leads to such a unique solution. Any other boundary values give rise to deviations from the physical solution with unrealistic physical parameters in the environment of the boundaries. The thickness of these boundary layers with unrealistic solutions is a few scale heights below the upper boundary of the model and a few tens of scale heights above the lower boundary of the model.
Volland, H.↗
The geomagnetically trapped radiation environment: A radiological point of view
The regions of naturally occurring, geomagnetically trapped radiation are briefly reviewed in terms of physical parameters such as; particle types, fluxes, spectrums, and spatial distributions. The major emphasis is placed upon a description of this environment in terms of the radiobiologically relevant parameters of absorbed dose and dose-rate and a discussion of the radiological implications in terms of the possible impact on space vehicle design and mission planning.
Holly, F. E.↗
Lunar surface magnetometer experiment
The Apollo 15 lunar-surface magnetometer (LSM) is one of a network of magnetometers that have been deployed on the moon to study intrinsic remanent magnetic fields and global magnetic response of the moon to large-scale solar and terrestrial magnetic fields. From these field measurements, properties of the lunar interior such as magnetic permeability, electrical conductivity, and temperature can be calculated. In addition, correlation with solar-wind-spectrometer data allows study of the the solar-wind plasma interaction with the moon and, in turn, investigation of the resulting absorption of gases and accretion of an ionosphere. These physical parameters and processes determined from magnetometer measurements must be accounted for by comprehensive theories of origin and evolution of the moon and solar system.
Dyal, P.↗
Locations of solar radio bursts
Measurements of the positions of the sources of solar radio bursts at decameter wavelengths, 20- to 60-MHz range, provide information about physical conditions in a region of the corona extending from about one-half to several solar radii from the surface of the sun. Position measurements in the 20- to 60-MHz range were made with the Clark Lake sweep-frequency grating interferometer. Although the resolution of the instrument is sufficient to measure source position accurately, the highly variable effect of refraction in the earth's ionosphere severely limits the observations, distorting position determinations to such an extent as to make much of the position data useless unless ionospheric refraction can be taken into account. A method was developed for the removal of the refractive effect from the data to permit determination of true source position. With this technique it is considered possible to measure spatial extent of radio sources that will provide information about emission processes and physical parameters in the corona.
Fitzenreiter, R.↗
Microwave emission from the moon
Measurements of the microwave emission from the moon and their interpretation in terms of the thermophysics of that body are reviewed. Variations of the brightness temperatures of the moon during a lunation and during eclipses when combined with infrared and radar measurements yield a precise set of physical parameters for the upper few meters of the lunar soil. These parameters include the density, thermal conductivity, dielectric constant, radio absorption coefficients, and the mean temperature gradiant.
Muhleman, D. O.↗
Theoretical determination of cesiated work functions
A computer program based on the theoretical work of Gyftopoulos, Steiner, and Levine on bimetallic systems and using a modified version of Wilkins' SIMCON subroutine SURFAS was written for the Univac 1108. This program, WFGSL, accepts the operating conditions and the physical parameters pertinent to the substrate and adsorbate, and outputs the field-free work function, electron current (Richardson equation), ion current (Saha equation), and fractional substrate coverage by the adsorbate. A brief description of the theory is presented together with a program description and listing. An application of the program to a bimetallic system of cesium (adsorbate) and rhenium (substrate) is also described.
Szejn, R. M.↗
Calibration of small gauge thermocouples.
A technique has been developed to dynamically calibrate fine wire thermocouples of 0.025 mm diam and smaller to 1625 K in less than 10 sec. In this method, the varying physical parameters present under typical dynamic heating conditions are simulated, and therefore, wire deterioration can be related to time, temperature, pressure, and atmosphere. A description of the equipment and procedures is given along with the preliminary results that correlate well with thermoelectric theory.
Stewart, W. F.↗
Evidence for the binary nature of Centaurus X-3 from Uhuru X-ray observations.
Analysis of data spanning a year of observations of the pulsating X-ray source Cen X-3 from Uhuru has revealed the existence of periodic variations in intensity of the source and correlated sinusoidal variations in the period of the 4.8-sec pulsations. We interpret this effect as due to an occulting binary system. The changes in intensity are then due to occultation of the X-ray source by a large massive companion, and the sinusoidal variations in the period of the 4.8-sec pulsations are due to Doppler effect. Physical parameters for the system are derived, and evidence for the existence and nature of an extended atmosphere surrounding the massive occulting object is discussed.
Schreier, E.↗
Mariner 6 and 7 ultraviolet spectrometer experiment - Photometry and topography of Mars.
From data obtained by the ultraviolet spectrometers aboard the Mariner 6 and 7 Mars missions the reflectivity of the illuminated disk of Mars was found to have two distinct spectral types, associated with polar and nonpolar regions. In this work the characteristic spectrum of nonpolar regions on Mars is discussed. An interpretation of the variation of the intensity at 3050 A due to surface pressure variations is given. A comparison of the ultraviolet observations with pressures inferred by the infrared spectrometer is used to test this interpretation and to determine physical parameters of Mars which lead to the observed reflectance. Earth based pressures obtained by broadening of the one-micron band of CO2 and radar topography are compared with the ultraviolet results.
Hord, C. W.↗
The structure of hydrophobic gas diffusion electrodes.
The 'flooded agglomerate' model of the Teflon-bonded gas diffusion electrode is discussed. A mathematical treatment of the 'flooded agglomerate' model is given; it can be used to predict the performance of the electrode as a function of measurable physical parameters.
Giner, J.↗
Fine structure in H II regions - Synthesis observations at 11 and 3.7 centimeters.
New high-resolution observations of several H II regions are reported. Improved values for the physical parameters describing the structure are deduced from their continuum spectra. The results are compared with estimates obtained by other means. The data are found to agree surprisingly well with the results of Andrews et al. (1971). The relation between the structure and the parent H II region is also investigated.
Balick, B.↗
The prospects for mineral analysis by remote infrared spectroscopy.
An investigation of the effects of physical parameters on the spectra of minerals has been carried out, and an attempt made to develop a comprehensive theory of the reflectance (or emittance) spectra of particulate surfaces. The theory involves the effects of particle size, surface roughness, porosity, and mixing ratios on the spectra of mineralogical assemblages. The true spectral information is represented by the refractive indices and absorption coefficients of the constituent minerals. The present theory and the Mie theory for a cloud of well separated quartz particles are compared, as well as theoretical and experimental reflectances of quartz powders, glass beads, and corundum powders. Experimental results of abrading sapphire are presented.
Aronson, J. R.↗