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71.
František Blahák Jan Laštovička Revievwer L. Křivský 《Studia Geophysica et Geodaetica》1980,24(1):60-64
¶rt;m uu n ¶rt;au m uu nu mau nam aum n. mu uu auam mmmuu uuu ¶rt;u u naam. a¶rt;am auu ¶rt; uuu n ¶rt;au m u u. a auu a¶rt;am nuu amm 245 . ¶rt;aam umnmau m a¶rt;a uu. 相似文献
72.
¶rt;m uu nau mu m a nu a¶rt;u ¶rt; D-amu u. a¶rt; m nu u u. u¶rt;a a a mu nma u nma mu m (20 ¶rt; 150 ). 相似文献
73.
J. Ilavský 《Mineralium Deposita》1976,11(1):93-110
During the course of the geotectonic development of the West Carpathians there were ore mineralisation periods, which are associated with different stratigraphical hiatuses. Hematite-magnetite ore was deposited in the first period between the Silurian and the Devonian. In both the Middle and the Upper Carboniferous, some stratiform siderite deposits originated, which were exploited in the vicinity of Dobiná and Mlynky during about the last 100 years. In the Permian, some haematite occurrences, fossil gold placers and uranium-bearing strata were formed, the last of which was exploited. Some minor haematite occurrences are widespread in the Lower Triassic. The same type of occurrence is known in the Upper Triassic and in the Lower Jurassic, too. In the Jurassic, small occurrences of manganese ore are known. Bauxite occurreces were found in the Middle and Upper Cretaceous, but they are very small. More important are the sedimentary manganese deposits, which were deposited in the Middle Eocene. These were exploited during the last 70 years. The fossil gold placers of the east Slovakian, Paleogene flysch series are very interesting from genetic point of view. The small kaoline, bauxite and silicate-nickel occurrences, which are associated with the alteration processes of basic rocks of different age, were found during the Miocene. The Quaternary period is well known for its gold placers, from which those of the Danube river as well as others were exploited in the past.
Nach einem Vortrag gehalten auf der Tagung des Lagerstättenausschusses der G. D. M. B. und der S. G. A. in Clausthal am 4. / 5. April 1975 相似文献
Nach einem Vortrag gehalten auf der Tagung des Lagerstättenausschusses der G. D. M. B. und der S. G. A. in Clausthal am 4. / 5. April 1975 相似文献
74.
Summary Results of computing the anomalies of the variable magnetic field, generated by a harmonically variable field of the H1,0-type in the model of a spherical Earth with an expressive bulge in the well-conducting part of the mantle, are presented. It was found that not only the radial, but also the tangential component of the magnetic field is disturbed above the bulge. The largest amplitudes of these changes can be observed over the area of the largest slope of the conductivity boundary if the exciting magnetic field is perpendicular to the surface of the interface. 相似文献
75.
76.
We propose that the europium excess in Precambrian sedimentary rocks, relative to those of younger age is derived from volcanic rocks of ancient island arcs, which were the source materials for the sediments. Precambrian sedimentary rocks and present-day volcanic rocks of island arcs have similar REE patterns, total REE abundances and excess Eu, relative to the North American shale composite. The present upper crustal REE pattern, as exemplified by that of sediments, is depleted in Eu, relative to chondrites. This depletion is considered to be a consequence of development of a grandioritic upper crust by partial melting in the lower crust, which selectively retains europium. 相似文献
77.
We studied the characteristics of the zebra-associated spike-like bursts that were recorded with high time resolution at 1420
MHz in four intervals (from 12:45 to 12:48 UT) during 5 August 2003. Our detailed analysis is based on the selection of more
than 500 such spike-like bursts and it is, at least to our knowledge, the first study devoted to such short-lived bursts.
Their characteristics are different from those pertinent to “normal” spike bursts, as presented in the paper by Güdel and
Benz (Astron. Astrophys.
231, 202, 1990); in particular, their duration (about 7.4 ms at half power) is shorter, so they should be members of the SSS (super short
structures) family (Magdalenić et al., Astrophys. J.
642, L77, 2006). The bursts were generally strongly R-polarized; however, during the decaying part of interval I a low R-polarized and L-polarized
bursts were also present. This change of polarization shows a trend that resembles the peculiar form of the zebra lines in
the spectral dominion (“V” like). A global statistical analysis on the bursts observed in the two polarimetric channels shows
that the highest cross-correlation coefficient (about 0.5) was pertinent to interval I. The zebras and the bursts can be interpreted
by the same double plasma resonance process as proposed by Bárta and Karlicky (Astron. Astrophys.
379, 1045, 2001) and Karlicky et al. (Astron. Astrophys.
375, 638, 2001); in particular, the spikes are generated by the interruption of this process by assumed turbulence (density or magnetic
field variations). This process should be present in the region close to the reconnection site (e.g., in the plasma reconnection outflows) where the density and the magnetic field vary strongly. 相似文献
78.
Seven Asteroids Studied from Modra Observatory in the Course of Binary Asteroid Photometric Campaign
Adrián Galád Petr Pravec Štefan Gajdoš Leonard Kornoš Jozef Világi 《Earth, Moon, and Planets》2007,101(1-2):17-25
We report lightcurves for five asteroids from the inner main belt—(1703) Barry, (2590) Mourão, (4022) Nonna, (5171) Augustesen, (23031) 1999 XX7—and for two near-Earth asteroids—(100004) 1983 VA, (144922) 2005 CK38—obtained at Modra Observatory as a part of binary asteroid photometric campaign. Estimated synodic rotational periods and amplitudes of their composite lightcurves were as follows: 107.1 ± 0.5 h, 0.5 mag for (1703) Barry; 15.59 ± 0.01 h, 0.49 mag for (2590) Mourão; 2.5877 ± 0.0005 h, 0.08 mag for (4022) Nonna; 474 ± 10 h, 0.8 mag for (5171) Augustesen; 3.075 ± 0.001 h, 0.43 mag for (23031) 1999 XX7; 3.1643 ± 0.0009 h, 0.11 mag for (100004) 1983 VA; 4.7894 ± 0.0005 h, 0.27 mag for (144922) 2005 CK38. The slow rotator (5171) Augustesen and possibly also (1703) Barry appear to be tumblers, though their precession periods can not be estimated from the available data. 相似文献
79.
G. Tommei A. Milani D. Vokrouhlický 《Celestial Mechanics and Dynamical Astronomy》2010,107(1-2):285-298
The Radio Science Experiment is one of the on board experiments of the Mercury ESA mission BepiColombo that will be launched in 2014. The goals of the experiment are to determine the gravity field of Mercury and its rotation state, to determine the orbit of Mercury, to constrain the possible theories of gravitation (for example by determining the post-Newtonian parameters), to provide the spacecraft position for geodesy experiments and to contribute to planetary ephemerides improvement. This is possible thanks to a new technology which allows to reach great accuracies in the observables range and range rate; it is well known that a similar level of accuracy requires studying a suitable model taking into account numerous relativistic effects. In this paper we deal with the modelling of the space-time coordinate transformations needed for the light-time computations and the numerical methods adopted to avoid rounding-off errors in such computations. 相似文献
80.
Martin Nekola René Hudec Martin Jelínek Matůš Kocka Petr Kubánek Filip Münz Cyril Polášek Vojtěch Šimon Jan Štrobl 《Experimental Astronomy》2010,28(1):79-85
We report on two small aperture robotic telescopes called BART and D50 operated in Ondřejov. Both telescopes are capable of
automatic observation of gamma ray burst (GRB) optical afterglows. Coordinates of GRBs are taken from alerts distributed via
Internet. Telescopes observe other interesting high energy sources when there is not any alert. The smaller telescope BART
has aperture D = 254 mm. The bigger telescope D50 has a primary mirror of diameter D = 500 mm. Both telescopes are controlled
by free software package RTS2 and are accessible through Internet. We describe the two telescopes and related software and
show some results such as our first observed optical counterpart of GRB. 相似文献