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511.
For 14 values of the mass parameter (from 0.0010 until 0.0150) the non-periodic Transtrojan orbits (aroundL
4 and L5) are investigated, which on the plane restricted problem of three bodies pass the point situated opposite to the body (looking from the main mass) with zero velocity in the rotating coordinate system. Results: The Transtrojan state contains a finite number of double librations (aroundL
4 and L5); this number decreases with growing value of the mass parameter. Above a value of mass parameter between 0.010 and 0.015 no further double-libration takes place. Certain topologic properties of the Transtrojan state are found; for example this state has a phase of narrowing and a phase of widening of the single librations; thereby the amplitudes of the librations fluctuate in a characteristic manner.The investigations will be published inAstronomische Nachrichten in German language.
Presented at the Conference on Celestial Mechanics, Oberwolfach, Germany, August 17–23, 1969. 相似文献
Numerische Untersuchungen Über Nicht-Periodische Transtrojaner-Bahnen
Presented at the Conference on Celestial Mechanics, Oberwolfach, Germany, August 17–23, 1969. 相似文献
512.
The 60-Hz electromagnetic fields in the Atlantic Ocean off Montauk Point, NY, and from Block Island Sound to the harbor in New London, CT, have been measured to determine the levels of interference to an extremely low frequency (ELF) receiver. Such data are needed to specify how close to the coastline an ELF receiver can come before 60-Hz external interference will degrade system performance. The data indicate that degradation to the ELF receiver from 60-Hz external interference will not occur offshore, but may occur within the confines of New London Harbor. 相似文献
513.
Dr. Bruno Brehler Dr. Helmut G. F. Winkler 《Contributions to Mineralogy and Petrology》1954,4(1-2):6-11
Zusammenfassung Die Struktur des K2MgF4 wurde untersucht. Es ergab sich: Raumgruppe I 4/m m m
2,a
0 = 3,977 Å,c
0 = 13,16 Å, Inhalt der Elementarzelle zwei Formeleinheiten. Die Struktur besteht aus Schichten zweidimensional-unendlich miteinander verknüpfter MgF6-Koordinationsoktaeder, was rich auch in der Art der Spaltbarkeit und Optik äußert.
Herrn Professor Dr.Carl W. Correns zum 60. Geburtstag gewidmet. 相似文献
Herrn Professor Dr.Carl W. Correns zum 60. Geburtstag gewidmet. 相似文献
514.
Mario Barbieri Adelia Penta Dr. Bruno Turi 《Contributions to Mineralogy and Petrology》1975,50(2):127-133
CaSO4 has been investigated at room temperature over the pressure range of 0 to 160 kbar. A reversible, sluggish transition that occurs at about 20 kbar with a volume change of about 4% has been confirmed. The x-ray powder data collected at pressure can be indexed on the monoclinic monazite structure cell (P21/n) which is considered to be the most likely model structure for the new HP CaSO4 phase. The transition is largely distortional and involves rotation and displacement, but essentially preserves the chains of edge shared CaO8(9) and SO4 polyhedra found in the orthorhombic anhydrite (Bbmm) structure. 相似文献
515.
In July 1994, the Shoemaker-Levy 9 (SL9) impacts introduced hydrogen cyanide (HCN) to Jupiter at a well confined latitude band around −44°, over a range of specific longitudes corresponding to each of the 21 fragments (Bézard et al. 1997, Icarus 125, 94-120). This newcomer to Jupiter's stratosphere traces jovian dynamics. HCN rapidly mixed with longitude, so that observations recorded later than several months after impact witnessed primarily the meridional transport of HCN north and south of the impact latitude band. We report spatially resolved spectroscopy of HCN emission 10 months and 6 years following the impacts. We detect a total mass of HCN in Jupiter's stratosphere of 1.5±0.7×1013 g in 1995 and 1.7±0.4×1013 g in 2000, comparable to that observed several days following the impacts (Bézard et al. 1997, Icarus 125, 94-120). In 1995, 10 months after impact, HCN spread to −30° and −65° latitude (half column masses), consistent with a horizontal eddy diffusion coefficient of Kyy=2-3×1010 cm2 s−1. Six years following impact HCN is observed in the northern hemisphere, while still being concentrated at 44° south latitude. Our meridional distribution of HCN suggests that mixing occurred rapidly north of the equator, with Kyy=2-5×1011 cm2 s−1, consistent with the findings of Moreno et al. (2003, Planet. Space Sci. 51, 591-611) and Lellouch et al. (2002, Icarus 159, 112-131). These inferred eddy diffusion coefficients for Jupiter's stratosphere at 0.1-0.5 mbar generally exceed those that characterize transport on Earth. The low abundance of HCN detected at high latitudes suggests that, like on Earth, polar regions are dynamically isolated from lower latitudes. 相似文献
516.
Bruno Bertotti 《Celestial Mechanics and Dynamical Astronomy》1988,44(1-2):31-44
Summary Two earth orbiting satellites with the same semimajor axes and eccentricities, but supplemental inclinations, define a direction — the bisector of their nodal lines — which is free from the secular motion due to the oblateness of the earth (Ciufolini 1986). We show that the inclination and the longitude of the node refer to the direction of the angular momentum of the earth. Because of the lunisolar precession and nutation, the longitude of the bisector so defined changes in a way dependent on the orientation of the angular momentum. If the relativistic Lense-Thirring precession is assumed, its measurement with two supplemental satellites will give information about the precessional and nutational constants.Research supported by the Piano Spazïale Nazionale of Italy. 相似文献
517.
518.
519.
520.
Bruno Simmersbach 《International Journal of Earth Sciences》1920,10(4-8):126-137
Ohne Zusammenfassung 相似文献