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991.
Sixty-one blue spectrograms of TX UMa were obtained in the years 1969–1970, mainly in phases close to the primary minimum of the eclipsing system. The radial velocity curve displays clear rotational effect from which much higher than synchronous rotational velocity of the blue (B8V) component has been formally derived. However, this discrepancy is probably due to the presence of the tenous accretion disk around the primary. The disk is apparently fed by the intermittent mass transfer as indicated by the occasional changes of orbital period of the system. From all available radial velocity data an improved set of spectroscopic orbital elements is derived. The behaviour of the spectral lines in and out of the primary minimum is compared. Metallic lines of the cold (F7IV) secondary component are clearly seen exclusively in phases 0.988 to 0.012.Paper presented at the 11th European Regional Astronomical Meetings of the IAU on New Windows to the Universe, held 3–8 July, 1989, Tenerife, Canary Islands, Spain. 相似文献
992.
L. F. Rodríguez-Ramos E. Ballesteros J. C. González C. Couros J. J. Fuensalida 《Astrophysics and Space Science》1990,171(1-2):319-322
So as to meet the requirements of high spatial resolution techniques, two data acquisition interfaces for ITV and IPD detectors have been developed. These permit a synchronized and simultaneous observation between both of them. The synchronized temporal resolution is 20ms, as well as the data of the ITV, while the reading interface from the IPD permits a temporal resolution of 50s. The ITV signal is stored on the video-recorder while the IPD interface is developed through transputers which store the data, with the time tags, on computer disc.Paper presented at the 11th European Regional Astronomical Meetings of the IAU on New Windows to the Universe, held 3–8 July, 1989, Tenerife, Canary Islands, Spain 相似文献
993.
994.
Álvaro-Francisco Morote-Seguido María Hernández-Hernández 《Geografisk tidskrift / udgivet af Bestyrelsen for Det Kongelige danske geografiske selskab》2016,116(2):190-201
The intense urbanization of the Mediterranean coast as a result of the development of residential-tourist activities since the 1960s, especially from the mid-1990s to 2008, has generated new urban environments associated with extensive urban typologies. These include gardens linked to houses with outdoor spaces that are shared between all of the residents of the residential developments. The aim of this study is to determine the main characteristics of these new urban green spaces and their effect on domestic water consumption in Alicante (Spain). To do this, we analysed the characteristics that define these types of gardens (surface area, density, plant species and irrigation system) and determined their water needs using the Water Use Classifications of Landscape Species method. The main conclusions are that the increase in paved areas is one of the strategies to reduce water consumption in spaces where turf grass is the most common plant species. This is due to increased water prices and lack of water resources. 相似文献
995.
996.
997.
998.
V. V. Korneev V. V. Krutov S. L. Mandelstam B. Sylwester I. P. Tindo A. M. Urnov B. Valníček I. A. Zhitnik 《Solar physics》1980,68(2):381-389
Spectra of 3 large flares on 24 Oct., 5 Nov. and 16 Nov. 1970 in the region = 1.75–1.95 Å, obtained with the help of the Intercosmos-4 satellite during solar activity maximum are given. The physical conditions at the initial and final (decaying) phases are mainly studied. The line spectra are compared with hard continuum in the region 8–80 keV and results of polarization measurements, obtained simultaneously aboard the same satellite. 相似文献
999.
1000.
Rafael Cid María-Eugenia San Saturio 《Celestial Mechanics and Dynamical Astronomy》1987,42(1-4):263-277
In this article we study the conditions for obtaining canonical transformationsy=f(x) of the phase space, wherey(y
1,y
2,...,y
2n
) andx(x
1,x
2,...,x
2m
) in such a way that the number of variables is increased. In particular, this study is applied to the rotational motion in functions of the Eulerian parameters (q
0,q
1,q
2,q
3) and their conjugate momenta (Q
0,Q
1,Q
2,Q
3) or in functions of complex variables (z
1,z
2,z
3,z
4) and their conjugate momenta (Z
1,Z
2,Z
3,Z
4) defined by means of the previous variables. Finally, our article include some properties on the rotational motion of a rigid body moving about a fixed point. 相似文献