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991.
Möglichkeiten der photometrischen Untersuchung von Kugelhaufen mittels photographischer Äquidensiten
A method of estimating the surface-brightness of globular cluster with equidensity curves is described. (Russian abstract) 相似文献
992.
993.
994.
George W.Housner 《地震工程与工程振动(英文版)》2007,6(1):I0001-I0001
Destructive earthquakes have caused great damage in China and the United States and collapsing buildings have caused many deaths and injuries. The field of earthquake engineering studies 相似文献
995.
W. R. Dick H. Lorenz P. Notni E. Schilbach R.-D. Scholz G. A. Richter 《Astronomische Nachrichten》1986,307(2):85-88
We have determined the positions of 65 compact extragalactic objects with magnitudes between 16m and 21m.7. The mean error of one position is about 0″.3 in α cos δ and in δ. Some hitherto unpublished redshifts are also listed. 相似文献
996.
R. W. John 《Astronomische Nachrichten》1986,307(5):303-305
In the vacuum case, Einstein's equations generalized by additive terms containing derivatives of the metric up to the 4th order are applied to cosmological Bianchi-type I model space-times. 相似文献
997.
998.
W. G
tz 《Astronomische Nachrichten》1984,305(1):17-24
In supplementing the photometric sequence in the central part of the Praesepe cluster and its extension to fainter stars a photographic photometry in UBV on plates of the 134/200/400 cm – Schmidt telescope of Karl-Schwarzschild-Observatory was done. The already known photometric data from stars obtained by HAFFNER , HECKMANN and WEIS were completed by (U – B) colours on the base of JOHNSON'S photoelectric photometry. Besides, a number of brighter and fainter stars, cluster members, white dwarfs inclusively and field stars were investigated to set up a photometric sequence down to V ≈ 18.m9. A finding chart where all the measured stars are marked is given. 相似文献
999.
F. W. Baier 《Astronomische Nachrichten》1984,305(3):111-118
The investigation of the distribution of number densities and radial velocities in the Perseus cluster led us to the conclusion that this cluster possesses dominant substructures. This result is in agreement with a corresponding result for the Hydra-I cluster and with former conclusions of different authors that substructures are a typical phenomenon for a high percentage of all clusters of galaxies. The complex of the Perseus cluster has a diameter of 60–80 minutes of arc. 相似文献
1000.
The development of the Lancaster Sound Trough Mouth Fan (TMF) and glacial history in Arctic Canada were studied using a high‐resolution seismic profile across the entire fan and two piston cores. Stacked tills separated by erosion surfaces on the shelf pass seaward through till deltas into thick transparent glacigenic debris flow (GDF) deposits on the slope, separated by thin, well‐stratified glaciomarine layers. An age model was built by ties to the Ocean Drilling Program Site 645. The deepest GDF on the seismic profile was indicative of the onset of shelf‐crossing glaciation in the Early Pleistocene. The transition of the growth of Lancaster Sound TMF from an aggradational sequence (unit M) to an aggradational–progradational sequence (unit F) occurred at the Middle Pleistocene transition in glacial cyclicity. In the most recent glacial cycle, GDF sheets were deposited during Heinrich events 4 and 2 according to the correlation of the main detrital carbonate beds in two piston cores. The outmost till wedge reflects the maximum advance of the grounding glacier, far seaward of previously proposed Last Glacial Maximum ice extent. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献