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421.
Izvestiya, Atmospheric and Oceanic Physics - In this paper we study the evolution of the matter distribution pattern of ink droplets falling freely into calm water and forming a cumulative back jet... 相似文献
422.
Zakharov V. S. Simonov D. A. Bryantseva G. V. Kosevich N. I. 《Izvestiya Atmospheric and Oceanic Physics》2019,55(7):721-730
Izvestiya, Atmospheric and Oceanic Physics - The results of the fractal analysis of a drainage network reconstructed using a digital elevation model and the structural and geomorphological analysis... 相似文献
423.
V. L. Afanasjev I. D. Karachentsev V. A. Lipovetsky H. Lorenz 《Astronomische Nachrichten》1979,300(2):77-79
The spectra of ten objects discovered by the Tautenburg objective prism survey were obtained at a higher spectral resolution in order to refine the selection criteria. We found four objects to be quasars and three MARKARIAN -type galaxies. 相似文献
424.
Elvis A. Shukla Jagdish Prasad M. S. S. Nagaraju Rajeev Srivastava D. L. Kauraw 《Journal of the Indian Society of Remote Sensing》2009,37(1):129-137
Soil resource characterization of Dhamni micro-watershed in Chandrapur district of Maharashtra was carried out using IRS-1D
LISS-III data in conjunction with field survey and ancillary data. The study indicates that nearly 84.2 per cent of the total
geographical area of the watershed is under cultivation. Forest (mainly degraded) occupy only 4.5 per cent area Whereas wasteland
with scrub cover 9.4 per cent area of the watershed. Nine soil series were tentatively identified and mapped as soil series
association in to five mapping units. These soils belong to order Inceptisol, Vertisol and Mollisol. Except the soils of wasteland
with scrub, other soils are moderately suitable for pigeonpea and soybean and have average to good productivity. 相似文献
425.
The long lost minor planet (843) Nicolaia was recovered with the 1 m ESO Schmidt telescope after 65 years. This was due to the careful examination of the old 1916 plates and the wellbalanced computation of search ephemerides. An improved orbit based on 19 right ascensions and 20 declinations from the two apparitions 1916 and 1981 is given. 相似文献
426.
We consider one-soliton perturbations of a flat Friedmann-Robertson-Walker (FRW) cosmological model, with an ideal fluid with pressure equal to the energy density (stiff fluid), in the case where the “pole trajectory” parameter is negative, introducing thereby singularities along certain null hypersurfaces. Starting with a metric that approaches asymptotically the FR W background, we show that it is possible to construct an extension through these hypersurfaces such that the energy momentum tensor Tab is finite and satisfies the energy conditions. The extension is only C1, providing a sort of “shock front” with continuity in Tab, that has an associated phase transition from null dust to stiff fluid, the transition being of the form described by CHANDRASEKHAR and XANTHOPOULOS. 相似文献
427.
Solar wind propagation from the point of measurement to an arbitrary target in the heliosphere is an important input for heliospheric, planetary and cometary studies. In this paper a new kinematic propagation method, the magnetic lasso method is presented. Compared to the simple ballistic approach our method is based on reconstructing the ideal Parker spiral connecting the target with the Sun by testing a previously defined range of heliographic longitudes. The model takes into account the eventual evolution of stream–stream interactions and handles these with a simple model based on the dynamic pressure difference between the two streams. Special emphasis is given to input data cleaning by handling interplanetary coronal mass ejection events as data gaps due to their different propagation characteristics. The solar wind bulk velocity is considered radial and constant. Density and radial magnetic field are propagated by correcting with the inverse square of the radial distance. The model has the advantage that it can be coded easily and fitted to the problem; it is flexible in selecting and handling input data and requires little running time. 相似文献
428.
429.
The arcuate pattern of the main Caledonian cleavage and associated fold axial plane traces in North Wales is due partly to NW-SE compression with tectonic transport to the southeast against the concealed crop of the Tan y grisiau Microgranite. Low-angle cleavage close to the microgranite is shown to be a local variant of the regional cleavage formed during the main deformation and not an earlier phase as previously supposed. Transcurrent movements along several major fault systems are also related to compression around the microgranite and the Harlech Dome block. 相似文献
430.
D. J. Galloway 《Astronomische Nachrichten》1984,305(5):224-224