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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.
Ohne ZusammenfassungMit 39 TextabbildungenDie vorliegende Arbeit wurde als Dissertation bei der Naturwissenschaftlichen Fakultät der Universität Würzburg 1958 eingereicht.  相似文献   
103.
The volume variation as a function of pressure along the jadeite–aegirine solid solution was determined at room temperature up to pressures between 6.5 and 9.7 GPa by single-crystal X-ray diffraction. The unit-cell volumes collected at room pressure for the different compositions indicate a slight deviation from linearity along the join. The pressure–volume data have been fitted using a third-order Birch-Murnaghan equation of state (BM3-EoS). The bulk modulus, K T0, varies from 134.0(7) GPa for pure jadeite to 116.1(5) GPa for pure aegirine. Its evolution with composition along the join is not linear and can be described by the following second order polynomial:
(1)
The value of the first pressure derivative K′ is close to 4 for all the samples investigated and can be used in a BM3-EoS to determine the volume variations of these pyroxenes up to 7–10 GPa. Along the join the highest compressibility among the crystallographic directions is always observed along a, however, the compression along b is the most affected by compositional changes. The strain ellipsoid analysis indicates that the major compression occurs on the (0 1 0) plane along a direction at about 145° to the c axis (from c to a). The anisotropy of the compression increases with increasing the aegirine component, as confirmed by the analysis of both the axial compressibility and the strain tensor.  相似文献   
104.
Some peak PM10 episodes, occurred during PM monitoring campaigns performed on October 2005 and February and June 2006 in Bari town, have been characterized. Moreover back trajectories of air masses and Principal Component Analyses were applied. Three of the peak PM10 episodes investigated were related to local emissions of primary pollutants during poor atmospheric dispersion conditions. The other two peak PM10 episodes considered are related with long range transport air masses toward Apulia region: in one case the chemical characterization and the back trajectories analysis indicate that high PM10 value detected is due to the Saharan dust advection in the Apulia region; in the other case air masses with different origin give rise to high PM10 value.Moreover PM10 daily mean concentrations, presented in this paper collected from January 2005 to August 2007 and obtained by automatic device in six stations of air quality monitoring networks in Bari territory, do not show a seasonal trend for PM10 concentrations, contrary to the PM10 trend shown in the towns of North Italy. This can be explained mostly considering that our region presents generally meteo-climatic conditions that favour pollutants dispersion.  相似文献   
105.
The wheatbelt of Western Australia shows a distinct Mediterranean climate with most of the rainfall occurring in the winter months. The main factor limiting plant production in this region is rainfall. Due to clearing of native vegetation, dryland salinity is a major problem in south-west Australia. Since the mid 1970s the region has experienced a significant decrease in winter rainfall. Across nine sites, growing season rainfall (May to October) decreased by an average of 11% and the sum of rainfall in June and July (June + July) decreased by 20%. We used the ASPIM-Nwheat model in combination with historic climate data to study the impact of recent climate change on the hydrology and production of wheat based farming systems by comparing results for before and after 1975. Despite the large decline in rainfall, simulated yields based on the actual weather data did not fall. At the same time, simulated drainage decreased by up to 95% which will significantly reduce the spread of dryland salinity. These results were due to the rainfall changes mainly occurring in June and July, a period when rainfall often exceeds crop demand and large amounts of water are usually lost by deep drainage. The findings will have significant implications for estimates of future climate change impacts in this region with changes in rainfall causing non-proportional impacts on production and hydrological aspects, such as deep drainage and waterlogging, where proportionality is often presumed.  相似文献   
106.
107.
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   
108.
109.
This paper reports the results of an investigation of the Weichselian Upper Pleniglacial loess sequences of Nussloch (Rhine Valley, Germany) based on stratigraphy, palaeopedology, sedimentology, palynology, malacology and geochemistry (δ13C), supported by radiocarbon, TL and OSL dating. Grain-size and magnetic susceptibility records are taken at 5 cm intervals from the Upper Pleniglacial (UPG) loess. The data indicate cyclic variations in loess deposition between ca 34 and 17 ka, when the sedimentation rate is especially high (1.0–1.2 m per ka for more than 10 m). The grain-size index (GSI: ratio of coarse silt versus fine silt and clay) shows variations, which are assumed to be an indirect measurement of wind intensity. The sedimentation rate, interpreted from the profiles, indicates high values in loess (Loess events LE-1 to LE-7) and low or negligible values in tundra gley horizons G1 to G8. OSL ages from the loess and 14C dates from organic matter in the loess show that loess deposition was rapid but was interrupted by shorter periods of reduced aeolian sedimentation. Comparison between the data from Nussloch and other European sequences demonstrates a progressive coarsening of the loess deposits between ca 30 and 22 ka. This coarsening trend ends with a short but major grain-size decrease and is followed by an increase to a new maximum at 20 ± 2 ka (“W” shape). Correlation between the loess GSI and the Greenland ice-core dust records, suggests a global connection between North Atlantic and Western European global atmospheric circulation and wind regimes. In addition, the typical Upper Pleniglacial loess deposition begins at ca 30–31 ka, close to Heinrich event (HE) 3, and the main period of loess sedimentation at about 25 ± 2 ka is coeval to HE 2. Correlation of magnetic susceptibility and grain-size records shows that the periods, characterised by high GSI, coincide with an increase in the amount of ferromagnetic minerals reworked from the Rhine alluvial plain. They suggest enhancement in the frequency of the storms from N–NW. These results are integrated within a palaeogeographical model of dust transport and deposition in Western Europe for the Weichselian Upper Pleniglacial (or Late Pleniglacial).  相似文献   
110.
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   
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