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101.
The six best known X-ray binaries are investigated according to the two different assumptions on the mechanism of matter supply. From the model of a semi-detached system with a point-like component, rather good estimates for the masses of the stars and the radius of the optical component can be deduced. The stellar wind model appears to be generally insufficient for driving the X-luminosity. Therefore, according to the mass-ratios, the stars may be at the beginning of mass-exchange. Only 3U 1700-37 shows inconsistent observational data.In the frame of the Roche model, the values of the contact phase angles, in the case of one star filling its lobe and a point-like companion, are given in tabular form in the Appendix, as a function of the mass-ratio and the orbital inclination angle. The limiting minimum inclination angle to have an eclipse is also given.This work has been partly supported by a contract of the Consiglio Nazionale delle Ricerche (CNR). 相似文献
102.
Bruno Ficke 《Mineralogy and Petrology》1961,7(4):337-436
Ohne ZusammenfassungMit 39 TextabbildungenDie vorliegende Arbeit wurde als Dissertation bei der Naturwissenschaftlichen Fakultät der Universität Würzburg 1958 eingereicht. 相似文献
103.
R. Bruno V. Carbone Z. Vörös R. D’Amicis B. Bavassano M. B. Cattaneo A. Mura A. Milillo S. Orsini P. Veltri L. Sorriso-Valvo T. Zhang H. Biernat H. Rucker W. Baumjohann D. Jankovičová P. Kovács 《Earth, Moon, and Planets》2009,104(1-4):101-104
At the end of August 2007, Venus, Earth and Ulysses were aligned within a few degrees. This unusual event gives the opportunity to attempt a coordinated study on the radial evolution of solar wind turbulence and coronal transients like CMEs between 0.7 and 1.4 AU. Interplanetary magnetic field data and moments of proton velocity distribution function such as density, speed and temperature are required for this programme and will be provided by ACE at Earth, Venus Express at Venus and Ulysses at 1.4 AU. This project has been recently proposed as a Coordinated Investigation Programme (CIP35) for the International Heliophysical Year. 相似文献
104.
In this paper we describe a new computing system array, designed, built and now used at the Space Astrophysics and Planetary Institute (IAPS) in Rome, Italy, for the INTEGRAL Space Observatory scientific data analysis. This new system has become necessary in order to reduce the processing time of the INTEGRAL data accumulated during the more than 9 years of in-orbit operation. In order to fulfill the scientific data analysis requirements with a moderately limited investment the starting approach has been to use a ??cluster?? array of commercial quad-CPU computers, featuring the extremely large scientific and calibration data archive on line. 相似文献
105.
We investigated the Coulomb stress changes in the active faults surrounding a moderate‐magnitude normal‐faulting earthquake (2009 L'Aquila, Mw 6.3) and the associated variations in the expected ground motion on regional probabilistic seismic hazard maps. We show that the static stress variations can locally increase the seismic hazard by modifying the expected mean recurrence time on neighbouring faults by up to ~290 years, with associated variations in the probability of occurrence of the maximum expected earthquake of up to ~2%. Our findings suggest that the increase in seismic hazard on neighbouring faults following moderate‐magnitude earthquakes is probably not sufficient to necessitate systematic upgrades of regional probabilistic seismic hazard maps, but must be considered to better address and schedule strategies for local‐scale mitigation of seismic risk. 相似文献
106.
Bruno Simmersbach 《International Journal of Earth Sciences》1920,10(4-8):158-182
Ohne Zusammenfassung 相似文献
107.
GPCC's new land surface precipitation climatology based on quality-controlled in situ data and its role in quantifying the global water cycle 总被引:10,自引:3,他引:10
Udo Schneider Andreas Becker Peter Finger Anja Meyer-Christoffer Markus Ziese Bruno Rudolf 《Theoretical and Applied Climatology》2014,115(1-2):15-40
In 1989, the need for reliable gridded land surface precipitation data sets, in view of the large uncertainties in the assessment of the global energy and water cycle, has led to the establishment of the Global Precipitation Climatology Centre (GPCC) at Deutscher Wetterdienst on invitation of the WMO. The GPCC has calculated a precipitation climatology for the global land areas for the target period 1951–2000 by objective analysis of climatological normals of about 67,200 rain gauge stations from its data base. GPCC's new precipitation climatology is compared to several other station-based precipitation climatologies as well as to precipitation climatologies derived from the GPCP V2.2 data set and from ECMWF's model reanalyses ERA-40 and ERA-Interim. Finally, how GPCC's best estimate for terrestrial mean precipitation derived from the precipitation climatology of 786 mm per year (equivalent to a water transport of 117,000 km3) is fitting into the global water cycle context is discussed. 相似文献
108.
The core of the turbidity maximum zone in the Saint-Lawrence Estuary is located in the North Channel and oscillates in front of the large (3×106 m2) intertidal flats and marshes of Cap Tourmente. It is shown that seasonal fluctuations in the intensity and the position of this core are mainly determined by suspended sediment exchanges between the channel and the marshes. Fine sediments, most of them found 20 km downstream in the channel off Cap Maillard in late winter and early spring, are advected upstream over the flats during the summer months by the tide. The deposition, favored by marsh plant growth, reaches 5×105 metric tons in three months. A period of intense erosion, at a mean rate of 4,500 metric tons per tide, coincides with the destruction of the plant cover by migratory geese. The material removed fills up the Chenal de l’Île d’Orléans upstream and is flushed back into the water column during the next spring freshette. This rotating seasonal sediment circulation, although very localized, exerts a major influence on the distribution and storage time of suspended particles in the upper estuary. 相似文献
109.
Alberto Omar Vazquez-Hernandez Gilberto Bruno Ellwanger Luís Volnei Sudati Sagrilo 《Applied Ocean Research》2006,28(6):398-406
The characteristic environmental load effect for the design of mooring systems of floating units can be defined by means of three procedures: (a) the one associated to an extreme sea state with a given return period, (b) the worst one from a set of sea states on a contour line associated to a return period or (c) the extreme one based on response statistics for a long-term period. This work presents the result of a reliability-based partial safety factor calibration study for a LRFD mooring line design criteria considering the three approaches mentioned above. The calibration exercise is applied to three FPSOs considering North Sea environmental conditions and different water depths: 200, 800 and 3000 m. The mooring systems investigated take into account mooring lines made up of chains and polyester ropes. It is shown that, among all cases investigated, the design procedure based on the long-term response is the one that presents less scattered reliability indices around the target level. 相似文献
110.
R. G. Gratton G. Bonanno P. Bruno A. CalÍ R. U. Claudi R. Cosentino S. Desidera F. Diego G. Farisato G. Martorana M. Rebeschini S. Scuderi 《Experimental Astronomy》2001,12(2):107-143
SARG is a cross dispersed echelle spectrograph in operation since late spring 2000 at the Italian Telescopio Nazionale Galileo
(TNG) 3.5 m telescope, La Palma. SARG offers both single object and long slit (up to 26 arcsec) observing modes covering a
spectral range from λ = 0.37 up to1 μm, with resolution ranging from R = 29,000 up to R = 164,000. Cross dispersion is provided by means of a selection of four grisms; interference filters may be used for the
long slit mode (up to 26 arcsec). A dioptric camera images the cross dispersed spectra onto a mosaic of two 2048 × 4096 EEV
CCDs (pixel size: 13.5 μm) allowing complete spectral coverage at all resolving power for λ < 0.8 μm. In order to reach a
high wavelength calibration precision an iodine-absorbing cell is provided. A Distributed Active Temperature Control System
(DATCS) maintains constant the temperature of all spectrograph components at a preset value. Early results show that SARG
works according to original specifications in terms of wavelength coverage, efficiency (measured peak efficiency is about
13%),resolution (maximum resolution R = 164,000 using a 0.3 arcsec slit, R ∼144,000 using an image slicer), and stability (preliminary estimates of radial velocity accuracy is ∼3 m/s using the iodine
cell and ±150 m/s without the iodine cell).
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献