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231.
Actual surface fields of meteorological variables 1–3 hours before the heavy showers are analyzed in detail for the purpose
of their specification with WRF-ARW model. The complex of hygrothermodynamic characteristics needed for this purpose is discovered.
The detailed satellite, radar, and synoptic data are also considered. 相似文献
232.
In certain areas of the Namib gravel plains a new Ariadna sp. was discovered. It rims its vertical burrow with a stone circle, made on average of seven quartz stones. Some mathematical relationships between hole diameter, stone sizes and weight, and animal size were studied. A correlation was found, and stone selection by this spider postulated. Different hypotheses on the adaptive value of stone circle are suggested. 相似文献
233.
Wide-angle vibroseis test across the Rhine graben 总被引:1,自引:0,他引:1
B. Damotte K. Fuchs E. Lüschen F. Wenzel R. Schlich G. Toreilles 《Geophysical Journal International》1987,89(1):313-318
Summary. As a joint operation of ECORS and DEKORP, a deep wide-angle seismic experiment using vibrators was carried out in the autumn of 1984. The object was to get information on the deep crust under the Rhine graben without crossing through sedimentary layers. Offsets were in the range of 50 to 89 km. In the first phase, two vibration points were executed in the Vosges mountains. A signal was received in the Black Forest from solely the farthest VP. In the second phase, fourteen VPs were executed in the Black Forest. No stacking or correlation was performed in the field in France. The quality of the results is good only if an equalization is applied before vertical stacking and correlation in the computing centre. 相似文献
234.
A. G. Bedregal A. Aragón-Salamanca M. R. Merrifield 《Monthly notices of the Royal Astronomical Society》2006,373(3):1125-1140
We present a study of the local B - and K s -band Tully–Fisher relation (TFR) between absolute magnitude and maximum circular speed in S0 galaxies. To make this study, we have combined kinematic data, including a new high-quality spectral data set from the Fornax cluster, with homogeneous photometry from the Third Reference Catalogue of Bright Galaxies and Two Micron All Sky Survey catalogues, to construct the largest sample of S0 galaxies ever used in a study of the TFR. Independent of environment, S0 galaxies are found to lie systematically below the TFR for nearby spirals in both optical and infrared bands. This offset can be crudely interpreted as arising from the luminosity evolution of spiral galaxies that have faded since ceasing star formation.
However, we also find a large scatter in the TFR. We show that most of this scatter is intrinsic, not due to the observational uncertainties. The presence of such a large scatter means that the population of S0 galaxies cannot have formed exclusively by the above simple fading mechanism after all transforming at a single epoch. To better understand the complexity of the transformation mechanism, we have searched for correlations between the offset from the TFR and other properties of the galaxies such as their structural properties, central velocity dispersions and ages (as estimated from line indices). For the Fornax cluster data, the offset from the TFR correlates with the estimated age of the stars in the individual galaxies, in the sense and of the magnitude expected if S0 galaxies had passively faded since being converted from spirals. This correlation implies that a significant part of the scatter in the TFR arises from the different times at which galaxies began their transformation. 相似文献
However, we also find a large scatter in the TFR. We show that most of this scatter is intrinsic, not due to the observational uncertainties. The presence of such a large scatter means that the population of S0 galaxies cannot have formed exclusively by the above simple fading mechanism after all transforming at a single epoch. To better understand the complexity of the transformation mechanism, we have searched for correlations between the offset from the TFR and other properties of the galaxies such as their structural properties, central velocity dispersions and ages (as estimated from line indices). For the Fornax cluster data, the offset from the TFR correlates with the estimated age of the stars in the individual galaxies, in the sense and of the magnitude expected if S0 galaxies had passively faded since being converted from spirals. This correlation implies that a significant part of the scatter in the TFR arises from the different times at which galaxies began their transformation. 相似文献
235.
236.
Robert G. Garrett 《Journal of Geochemical Exploration》1974,3(3):277-289
Data for the mean mercury contents of some granitoid rocks of the Yukon are presented. A correlation of high mercury content with plutons postulated to be the sources, or genetically related to the sources, of the alluvial gold deposits of the McQuesten area is established. In addition a relation is indicated between high mercury content in one intrusion and high content in the Palaeozoic shale host rock. A limited amount of data is presented on the mercury content of the Proterozoic and Palaeozoic rocks of the sampled area. 相似文献
237.
238.
Data are presented on some structure parameters of mesoscale turbulence mechanisms playing a significant role in the troposphere-stratosphere
exchange in the tropical tropopause layer and in the lower stratosphere. The data are obtained in the framework of the international
aircraft AMMA experiment in Burkina Faso (West Africa) in August 2006. 相似文献
239.
Results of lithostratigraphic and mineral magnetic analysis of two surficial sediment cores (21 cm and 45 cm in length) collected from the Southern basin of Lake Baikal at a water depth of 1390 m, are presented. The sediments have been measured for a wide range of mineral magnetic parameters in order to assess their value in the identification of turbidite layers. Particle size and geochemical data are also presented and these explain some of the down core variations in magnetic mineralogy. It is suggested that changes in the particle size frequency distributions down core may be related to fossil diatom shells. One of the cores has been dated using 210Pb. The sediment cores were cross-correlated using low frequency magnetic susceptibility (f) and these cores can also be correlated with a nearby core collected earlier in 1992. Changes in the magnetic parameters of lf, IRMs and HIRM210 suggest that there are significant changes in the concentration of ferrimagnetic minerals in the sediment cores, indicating changing sediment sources and/or increasing concentrations of spheroidal carbonaceous particles and the dissolution of minerals through reduction below the oxidised layer within the sediment core. 相似文献
240.
Simulation of the full two rigid body problem using polyhedral mutual potential and potential derivatives approach 总被引:3,自引:0,他引:3
Eugene G. Fahnestock Daniel J. Scheeres 《Celestial Mechanics and Dynamical Astronomy》2006,96(3-4):317-339
Herein we investigate the coupled orbital and rotational dynamics of two rigid bodies modelled as polyhedra, under the influence of their mutual gravitational potential. The bodies may possess any arbitrary shape and mass distribution. A method of calculating the mutual potential’s derivatives with respect to relative position and attitude is derived. Relative equations of motion for the two body system are presented and an implementation of the equations of motion with the potential gradients approach is described. Results obtained with this dynamic simulation software package are presented for multiple cases to validate the approach and illustrate its utility. This simulation capability is useful both for addressing questions in dynamical astronomy and for enabling spacecraft missions to binary asteroid systems. 相似文献