Theory of absorption of ultrasound by free electrons in metals in a quantized magnetic field. Part 2 - Propagation of sound along the magnetic field
Sound and ultrasound propagation and absorption along quantized magnetic field
Filippov, B. N.↗
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The Magnetic and Related Stars, American Astronomical Society and NASA, Symposium on the Magnetic and Other Peculiar and Metallic-Line A Stars, Goddard Space Flight Center, Greenbelt, MD., November 8- 10, 1965, Proceedings.
Magnetic and related stars - AAS and NASA Conference, Goddard Space Flight Center, November 1965
Cameron, R. C.↗
Measurement of magnetic fields in prominences and the structure of the magnetic field in the region of chromospheric filaments
Magnetic field measurement in solar prominences and structure in region of chromospheric filaments
Ioshpa, B. A.↗
Generation of low magnetic field environment for study of space null magnetic field effects on man.
Shield facility and Helmholtz coil system used to investigate chronic effects on man of zero magnetic field regulated to cancel geomagnetic field variations
Beischer, D. E.↗
Low viscosity magnetic fluid obtained by the colloidal suspension of magnetic particles Patent
Low density and low viscosity magnetic propellant for use under zero gravity conditions
Papell, S. S.↗
Comparison of the mean photospheric magnetic field and the interplanetary magnetic field
Photospheric and interplanetary magnetic field polarity and magnitude comparison, using Explorer observations
Colburn, D. S.↗
Tests of permanent magnet and superconducting magnet MPD thrusters
Radiation cooled MPD thrustor with permanent and superconducting magnets, describing test facilities and measurement techniques for performance tests
Bishop, A. R.↗
The mean photospheric magnetic field from solar magnetograms Comparisons with the interplanetary magnetic field.
Large-scale averages of daily solar magnetograms have been compared by cross-correlation with the interplanetary magnetic sector pattern during a 2.5 yr interval. A significant correlation was found at a lag of about 4.5 days, with the amplitude of the correlation depending on the area included in the magnetogram averages. The highest correlation was found when an area of one quarter of the solar disk was used, which is consistent with the idea that the photospheric features which are to be associated with the interplanetary sector pattern are large scale features.
Scherrer, P. H.↗
Magnetic phases in lunar material and their electron magnetic resonance spectra - Apollo 14.
Electron magnetic resonance spectra of soil samples 14163,68, 14148,31, 14149,47, 14156,31, and 14003,60, and of fragmental rocks 14301,66, 14303,42, 14310,68, 14311,36, 14318,36, and 14321,166 have been recorded at 9 and 35 GHz at 300 K and at 9 GHz at 130 K. One spectral component, the characteristic ferromagnetic resonance, of all the soil samples is 50 to 1000 times more intense than any other component in the soils or in the spectra of the rocks. The intensity of this component in Apollo 11, Apollo 12, and Apollo 14 soils varies only within one order of magnitude. It varies with depth below lunar surface but is not correlated with depth. The intensity does not have any correlation with the fraction of glassy particles nor with the fraction of anorthositic particles.
Weeks, R. A.↗
Convection and magnetic fields in an atmosphere with constant temperature gradient. II - The supergranules and magnetic fields
The hydrodynamic properties of convective motions in a stratified atmosphere suggest that the supergranules in the solar photosphere extend to depths in excess of their horizontal diameters. The calculations presented here show that the weak fields which appear at the photosphere are as strong as, or stronger than, the horizontal fields anywhere in the supergranules below the surface. Hence the general 10 to 100 gauss azimuthal field of the sun, whose presence is indicated by the emerging bipolar magnetic regions, must lie below the base of the supergranules, i.e., below a depth probably of the order of 20,000 to 50,000 km. Presumably then the azimuthal field is generated by nonuniform rotation below the supergranule convection and does not appear in the supergranule layer because of the high rate of turbulent diffusion loss from that layer.
Parker, E. N.↗
Effect of interplanetary magnetic field on ionosphere over the magnetic equator
Large and quick changes of the latitude of the interplanetary magnetic field from its southward to northward direction are shown to be associated with the disappearance of the Es-q layer (Knecht, 1959) at the equatorial ionosphere during the daytime or with the reversal of E region horizontal and F region vertical electron drifts during both night and day. This phenomenon is suggested as the imposition of an electric field in the ionosphere in a direction opposite to that of the Sq electric field. The resultant electrostatic field on the equatorial ionosphere would be decreased or even reversed from its normal direction, resulting in the reduction of electron drift velocity. When the normal Sq field is over-compensated by the magnetospheric electric field, the electron drifts are reversed and the irregularities in the E region due to the cross-field instabilities are inhibited, resulting in the sudden disappearance of the Es-q layers.
Rastogi, R. G.↗
Magnetic stirling cycles: A new application for magnetic materials
The elements of the cycle are summarized. The basic advantages include high entropy density in the magnetic material, completely reversible processes, convenient control of the entropy by the applied field, the feature that heat transfer is possible during all processes, and the ability of the ideal cycle to attain Carnot efficiency. The mean field theory is used to predict the entropy of a ferromagnet in an applied field and also the isothermal entropy change and isentropic temperature change caused by applying a field. The results for isentropic temperature change are compared with experimental data on Gd. Coarse mixtures of ferromagnetic materials with different Curie points are proposed to modify the path of the cycle in the T-S diagram in order to improve the efficiency or to increase the specific power.
Brown, G. V.↗
Spatial distribution of large-scale solar magnetic fields and their relation to the interplanetary magnetic field
The spatial organization of the observed photospheric magnetic field as well as its relation to the polarity of the IMF have been studied using high resolution magnetograms from the Kitt Peak National Observatory. Systematic patterns in the large scale field are due to contributions from both concentrated flux and more diffuse flux. The polarity of the photospheric field, determined on various spatial scales, correlates with the polarity of the IMF. Analyses based on several spatial scales in the photosphere suggest that new flux in the interplanetary medium is often due to relatively small photospheric features which appear in the photosphere up to one month before they are manifest at the earth.
Levine, R. H.↗
The elements of the Earth's magnetism for the Epochs 1600, 1650, 1700, 1780, 1842 and 1885, and their secular changes derived from observations calculated using the coefficients of the Gaussian "General Theory of Earth's Magnetism"
After a historical review of the theory of the Earth's magnetism, the author indicates how the theory may be improved and gives results of his own calculations for the Epoch 1842.
Fritsche, H.↗
On the determination of the coefficients of the Gaussian general theory of the Earth's magnetism for the year 1885 and about the relationship of the three Earth-magnetic elements
An attempt is made to judge the value of the Gaussian series for the Earth's magnetism. The computation employed to do this uses the method of the least and greatest coefficients. The number of unknown which had to be calculated from the individual groups was at most only four. All symbols of Gauss were retained.
Fritsche, H.↗
Magnetic cristobalite (?) - A possible new magnetic phase produced by the thermal decomposition of nontronite
The effect of heat treatment for 1 h or more at 900-1000 C on the magnetic properties of nontronite, an iron-rich smectite clay thought to be an important component of Martian regolith, is investigated experimentally, extending the findings of Moskowitz and Hargraves (1982). The results are presented in graphs and tables and discussed. A phase with Curie temperature 200-220 C, remanent coercivity greater than 800 mT, and a type-2 room-temperature-coercivity response to thermomagnetic cycling is observed and attributed to an iron-substituted cristobalite which may form by topotactic growth from a smectite precursor.
Moskowitz, B. M.↗
Geological reasons for change in intensity of linear magnetic anomalies of the Kursk magnetic anomaly
The geological reasons for fluctuations in the anomalous field intensity along the polar axes were examined. The Kursk magnetic anomaly is used as the basis for the study. A geological-geophysical section was constructed which used the results of the interpretation of gravimagnetic anomalies.
Zhavoronkin, I. A.↗
A flying superconducting magnet and cryostat for magnetic suspension of wind-tunnel models
The engineering practicality of a persistent high-field superconducting solenoid cryostat as a magnetic suspension and balance system (MSBS) for wind-tunnel testing of aircraft and missile models is examined. The test apparatus is a simple solenoid of filamentary NbTi superconductor with a cupronickel matrix. The apparatus, with a length-to-diameter ratio of 6 to 1 and a radius of 32 mm, used a 0.25 mm wire with a critical current of 27 A in an external field of 6 T. The total heat inleak of 150 mW was achieved. Helium boiloff rates were tested over a range of operating conditions, including pitch attitudes from 10 deg nose down to 90 deg nose up; the rate was estimated as low, but the aerodynamic acceptability of venting gaseous helium has not been determined. It is shown that the effectiveness of the concept increases with increasing scale, and performance in excess of that of conventional ferromagnets is achievable with reduction in size and costs, and with aptness to transonic wind-tunnel testing. Detailed specifications and schematics are included.
Britcher, C.↗