996 resultados para 7140-246
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This study investigates the landscape evolution and soil development in the loess area near Regensburg between approximately 6000-2000 yr BP (radiocarbon years), Eastern Bavaria. The focus is on the question how man and climate influenced landscape evolution and what their relative significance was. The theoretical background concerning the factors that controlled prehistoric soil erosion in Middle Europe is summarized with respect to rainfall intensity and distribution, pedogenesis, Pleistocene relief, and prehistoric farming. Colluvial deposits , flood loams, and soils were studied at ten different and representative sites that served as archives of their respective palaeoenvironments. Geomorphological, sedimentological, and pedological methods were applied. According to the findings presented here, there was a high asynchronity of landscape evolution in the investigation area, which was due to prehistoric land-use patterns. Prehistoric land use and settlement caused highly difIerenciated phases of morphodynamic activity and stability in time and space. These are documented at the single catenas ofeach site. In general, Pleistocene relief was substantially lowered. At the same time smaller landforms such as dells and minor asymmetric valleys filled up and strongly transformed. However, there were short phases at many sites, forming short lived linear erosion features ('Runsen'), resulting from exceptional rainfalls. These forms are results of single events without showing regional trends. Generally, the onset of the sedimentation of colluvial deposits took place much earlier (usually 3500 yr BP (radiocarbon) and younger) than the formation of flood loams. Thus, the deposition of flood loams in the Kleine Laaber river valley started mainly as a consequence of iron age farming only at around 2500 yr BP (radiocarbon). A cascade system explains the different ages of colluvial deposits and flood loams: as a result of prehistoric land use, dells and other minor Pleistocene landforms were filled with colluvial sediments. After the filling of these primary sediment traps , eroded material was transported into flood plains, thus forming flood loams. But at the moment we cannot quantify the extent ofprehistoric soil erosion in the investigation area. The three factors that controlled the prehistoric Iandscapc evolution in the Ioess area near Regensburg are as follows: 1. The transformation from a natural to a prehistoric cultural landscape was the most important factor: A landscape with stable relief was changed into a highly morphodynamic one with soil erosion as the dominant process of this change. 2. The sediment traps of the pre-anthropogenic relief determined where the material originated from soil erosion was deposited: either sedimentation took place on the slopes or the filled sediment traps of the slopes rendered flood loam formation possible. Climatic influence of any importance can only be documented as the result of land use in connection with singular and/or statistic events of heavy rainfalls. Without human impact, no significant change in the Holocene landscape would have been possible.
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We present a parallax measurement for the very cool degenerate WD 0346+246, the serendipitous discovery of which was reported by Hambly et al, We find an absolute parallax of 36 +/- 5 mas, yielding a distance estimate of 28 +/- 4pc. The resulting absolute visual magnitude of the object is M-V = 16.8 +/- 0.3, making it the second-lowest luminosity white dwarf currently known. We use the distance estimate and measured proper motion to show that the object has kinematics consistent with membership of the Galactic halo. WD 0346+246 is therefore by far the coolest and least luminous of only a handful of plausible halo white dwarf candidates. As such, the object has relevance to the ongoing debate concerning the results of microlensing experiments and the nature of any baryonic dark matter component to the Galactic halo residing in stellar remnants.
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We report the serendipitous discovery of a new, very low luminosity, cool degenerate in the region of Taurus. The object was found as a very high proper-motion star (mu = 1.'' 3 yr(-1)) on seven I-band UK Schmidt Telescope plates, dating from 1987 to 1994, via digitized scans from the new, fast, high-precision microdensitometer SuperCOSMOS. Photometry and spectrophotometry indicate that the object has a temperature comparable to those of the handful of coolest white dwarfs currently known (T similar to 3900 K). We discuss the relevance of this discovery to current research concerning Galactic structure and evolution.
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Generally coarse grained, with a few different fine grained domains. Clasts range from small to large, ranging from sub-angular to sub-rounded in shape. Domain boundaries are clear, and the sample also contains rotation structures and lineations.
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Butterfat is usually the most expensive ingredient of ice cream; hence, great care is necessary in controllng its use. The manufacturer of ice cream, whether doing a large or a small volume of business, must manufacture a product that will comply with the established fat standard. Some means of determining the percentage of butterfat in the product must be available in order to establish this control. This 1930 research bulletin discusses the different testing equipment used to test butterfat in ice cream.
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3 Briefe zwischen Graf Lazy Henckel von Donnersmarck und Max Horkheimer, 1968; 2 Briefe zwischen Gräfin Nina Henckel von Donnersmarck und Max Horkheimer, 1968; 4 Briefe zwischen der Sängerin Carla Henius und Max Horkheimer, 1970-1971; 1 Brief an K. H. Hennings von Max Horkheimer, 1967; 4 Briefe zwischen Professor Wilhelm Hennis und Max Horkheimer, 1971; 1 Brief an Professor Dieter Henrich von Max Horkheimer, 1964; 2 Briefe zwischen Caroline Hergert und Max Horkheimer, 1970; 1 Brief von Professor Fred Herman an Max Horkheimer, 1959; 2 Briefe zwischen der Fachschülerin Dora Herrmann und Max Horkheimer, 1972; 2 Briefe zwischen Professor Franz Herrmann und Max Horkheimer, 1970; 6 Briefe zwischen Dr. phil. Gert-Julius Herrmann und Max Horkheimer, 1968; 2 Briefe zwischen Dipl. Kfm. Dr. Dr. Otto O. Herz und Max Horkheimer, 1969; 4 Briefe zwischen Professor und Museumsdirektor Erich Herzog und Max Horkheimer, 1970; 2 Briefe zwischen Hans Eberhard Hess und Max Horkheimer, 1970; 16 Briefe zwischen Professor Eugen Hess-Baer und Max Horkheimer, 1966-1971; 3 Briefe zwischen Karl Hess und Max Horkheimer, 1969-1971; 1 Drucksache von Pfarrer Walter Hess, 1971; 6 Briefe zwischen dem Bankier Walter Hesselbach und Max Horkheimer, 1971-1973; Drucksachen vom Hessischen Kreis, 1968; Briefe zwischen dem Hessischen Landesmuseum Darmstadt und Max Horkheimer, 1969; 25 Briefe zwischen Professor Heinz Joachim Heydorn und Max Horkheimer, 1965-1973; 2 Briefe zwischen Dr. Karl Heymann und Max Horkheimer, 1970; 1 Brief an den Hippokrates-Verlag von Max Horkheimer, 1971; 9 Briefe zwischen Walter Hirschmann und Max Horkheimer, 1969-1971;