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51.
Kurt Wegener 《Pure and Applied Geophysics》1959,43(1):278-284
Summary The development of the law of radiation, and his consequences, shortly exposed.
Résumé La loi de la radiation, developpement et consequences.相似文献
52.
Dr. Kurt v. Gehlen 《Contributions to Mineralogy and Petrology》1960,7(5):340-388
Quantitative determinations of preferred orientation of opaque minerals have been made only in a few cases by measuring cleavage faces (galena,D. Schachner-Korn). In this paper several methods are investigated critically which are likely to allow the determination of pole figures of ore minerals in a reasonable time. In the first part the special difficulties are discussed which occur in measurements of preferred orientation with X-ray pole figure goniometers (reflection method byL. G. Schulz) when the specimen consists of more than one mineral, when the mineral investigated is coarse-grained, and when the specimen is small. A critical discussion of instrumental errors is included. This method can now also be applied to the determination of preferred orientation in rocks, ceramic materials, etc. In the second part optical methods are given which include the construction of pole figures from measurements of bireflection and polarization figures of uniaxial minerals in reflected light. Examples of pole figures of pyrrhotite, hematite, pyrite, sphalerite, and chromite are given.
Der Naturwissenschaftlichen Fakultät der Friedrich-Alexander-Universität Erlangen als Habilitationsschrift vorgelegt. 相似文献
Der Naturwissenschaftlichen Fakultät der Friedrich-Alexander-Universität Erlangen als Habilitationsschrift vorgelegt. 相似文献
53.
Kurt Bender Ulrich Chorus Raymond Nybro Robert Sanderson Ingrid Weiss 《Pure and Applied Geophysics》1957,38(1):265-285
Summary UsingCraddock's method of representing the annual temperature variation by a two-term harmonic form fitted to monthly means, the harmonic coefficients of 63 stations in western Europe and around the Mediterranean Sea, as well as the 5-day normals for 24 Mediterranean stations, were computed and tabulated. In addition, some of the harmonic coefficients were charted and isoplethed, showing very distinctly the influence of continentality and topography. These charts, together withCraddock's charts for northern and northwestern Europe, provide fairly complete coverage of Europe and the Mediterranean area.This paper was prepared in the offices of the Technical Support Division of the 2d Weather Wing, United States Air Force, as a matter of routine business. The information contained herein was presented at the 5th Meeting of the Italian Society of Geophysics and Meteorology by Dr.Ingrid Weiss (Genoa: 23–25 April 1957). Since the paper is of general interest to all meteorologists of the Mediterranean area, it is published here with the permission of the originating agency as «Mémoire No. 3 du Centre International de Recherches sur la Météorologie de la Méditerranée (CIRMM)». 相似文献
54.
Rainer Roth 《Boundary-Layer Meteorology》1970,1(2):131-136
A model is described, in which the mean vertical wind profile and turbulence spectra at different heights are calculated for a turbulent boundary layer without thermal stratification. The model makes use of Heisenberg's formula for the transfer of turbulent energy and is based on the assumption of a constant shearing stress in that boundary layer. As a result, a logarithmic wind profile follows with 0.39 as the value of von Kármán's constant, which is — in this model — strongly related to the inertial subrange of the turbulent energy spectra and therefore to the Kolmogoroff constant.This paper is based on studies done by the author during a one-year visit to CSIRO Division of Meteorological Physics, Aspendale, Australia, and was presented at the AGARD Specialists Meeting on The Aerodynamics of Atmospheric Shear Flows sponsored by the Fluid Dynamics Panel at Munich, Germany, during 15–17 Sept. 1969. 相似文献
55.
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57.
Ohne Zusammenfassung 相似文献
58.
This paper outlines recent developments in computer mapping and points out its importance for visualizing contents of geographic information systems. The authors present an integrated system of mapping packages and spatial-data files. Map examoles generated with this system are used to illustrate characteristics of various computer-mapping methods. The diversity of displays created from a single set of data demonstrates that mapping from automated display systems requires the user to take some decisions which have to be based on an understanding of the phenomena displayed, of cartographic communication, and of technical aspects of automated map processing. 相似文献
59.
The re-entry phase of a highly eccentric satellite is discussed. Numerical simulations allowing the prediction of the exact date of re-entry of a highly eccentric satellite are exposed.It is shown that under very particular circumstances the life of the satellite can be extended by a few days. The number of final revolutions of the rapidly contracting orbit depends critically on the air density between 70 km and 100 km.Re-entry of the European scientific satellite HEOS-1 predicted for 28 October, 1975 is near such a situation. 相似文献
60.
Two extreme ultraviolet (EUV) spectrophotometers flown in December 1978 on Venera 11 and Venera 12 measured the hydrogen Lyman α emission resonantly scattered in the atmosphere of Venus. Measurements were obtained across the dayside of the disk, and in the exosphere up to 50,000 km. They were analyzed with spherically symmetric models for which the radiative transfer equation was solved. The H content of the Venus atmosphere varies from optically thin to moderately thick regions. A shape fit at the bright limb allows one to determine the exospheric temperature Tc and the number density nc independently of the calibration of the instrument or the exact value of the solar flux. The dayside exospheric temperature was measured for the first time in the polar regions, with Tc = 300 ± 25°K for Venera 11 (79°S) and Tc = 275 ± 25°K (59°S) for Venera 12. At the same place, the density is nc = 4?2+3 × 104 atom.cm?3, and the integrated number density Nt from 250 to 110 km (the level of CO2 absorption) is 2.1 × 1012 atom.cm?2, a factor of 3 to 6 lower than that predicted in aeronomical models. This probably indicates that the models should be revised in the content of H-bearing molecules and should include the effect of dynamics. Across the disk the value of Nt decreases smoothly with a total variation of two from the morning side to the afternoon side. Alternately it could be a latitude effect, with less hydrogen in the polar regions. The nonthermal component if clearly seen up to 40,000 km of altitude. It is twice as abundant as at the time of Mariner 10 (solar minimum). Its radial distribution above 4000 km can be simulated by an exospheric distribution with T = 1030K and n = 103 atom.cm?3 at the exobase level. However, there are less hot atoms between 2000 and 4000 km than predicted by an ionospheric source. A by-product of the analysis is a determination of a very high solar Lyman α flux of 7.6 × 1011 photons (cm2 sec Å)?1 at line center (1 AU) in December 1978. 相似文献