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121.
María Luisa García Vargas Angeles I. Díaz Elena Terlevich Roberto Terlevich 《Astrophysics and Space Science》1993,205(1):85-89
In the frame of the Starburst Model for AGN, we show that the evolution of a massive stellar cluster in a high metallicity environment can reproduce the observed equivalent widths of Ca II triplet lines in absorption in Starburst and active galactic nuclei. In the case of Starburst galaxies, this strength, together with the emission-line ratio [O II]/[O III], can be used to determine the age of the cluster. The strength of the Ca II lines is mainly governed by the age of the stellar cluster through the presence of red supergiant stars. 相似文献
122.
Angeles I Díaz Miguel Sánchez Portal Roberto Terlevich Elena Terlevich 《Astrophysics and Space Science》1990,171(1-2):29-41
We present CCD surface photometry of the central region of the bright Seyfert 1 galaxy NGC 4151. The observations were obtained under excellent seeing conditions (0.75 FWHM). Morphological parameters for the bulge of the galaxy are estimated from the observed broad bandV, R, andI surface brightness profiles.From the analysis of the colour maps two distinct nuclear structures emerge perpendicular to each other. One of them is elliptically elongated at PA angle 50°. This direction is close to the direction of the radio jets and coincides with the Extended Narrow Emission Line Region (ENELR). Its extension is about 7 arc sec and its colours are bluer than the surronding bulge. The second structure is smaller in extension (about 1 arc sec) and is elongated at PA130°. Its colours are redder than those of the surrounding bulge. It is suggested that this might constitute areal extension of the Broad Line Region (BLR).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
123.
Matyasovszky István Makra László Tusnády Gábor Csépe Zoltán Nyúl László G. Chapman Daniel S. Sümeghy Zoltán Szűcs Gábor Páldy Anna Magyar Donát Mányoki Gergely Erostyák János Bodnár Károly Bergmann Karl-Christian Deák Áron József Thibaudon Michel Albertini Roberto Bonini Maira Šikoparija Branko Radišić Predrag Gehrig Regula Rybníček Ondřej Severova Elena Rodinkova Victoria Prikhodko Alexander Maleeva Anna Stjepanović Barbara Ianovici Nicoleta Berger Uwe Seliger Andreja Kofol Weryszko-Chmielewska Elżbieta Šaulienė Ingrida Shalaboda Valentina Yankova Raina Peternel Renata Ščevková Jana Bullock James M. 《Theoretical and Applied Climatology》2018,133(1-2):277-295
Theoretical and Applied Climatology - The drivers of spatial variation in ragweed pollen concentrations, contributing to severe allergic rhinitis and asthma, are poorly quantified. We analysed the... 相似文献
124.
Alexei V. Ivanov Elena I. Demonterova Sergei V. Rasskazov Tatyana A. Yasnygina 《Journal of Earth System Science》2008,117(1):1-21
Siberian Traps Large Igneous Province (STLIP) is one of the most voluminous volcanic provinces on Earth. The dominant erupted
rocks are low-Ti basalts, which make up 80% by volume of the classical Noril’sk lava sequence. In the west Siberian basin
and Maymecha-Kotuy area, the low-Ti basalts make up about 99% and 50% by volume, respectively. Dolerite sills in the Angara-Taseevskaya
Syncline at the southeastern STLIP exhibit trace element patterns and Sr isotope ratios typical of the low-Ti basalts of the
Noril’sk sequence. The most Mg-rich (MgO 9.5–11 wt%) and hence least differentiated dolerites are characterized by trace element
patterns with Ta-Nb depletion, low Ce/Pb and high Sr/Pr. These trace element features are similar to water-saturated, mantle
wedge-derived island arc basalts. These imply an important role of subduction fluid-derived trace elements in the source of
melting beneath the Angara-Taseevskaya Syncline and other regions of the STLIP. Less magnesium rocks (MgO 3.8–6.1 wt%) with
less prominent Ta-Nb depletion, higher Ce/Pb and lower Sr/Pr could be produced via olivine-plagioclase fractionation of primary
high-magnesium melts. 相似文献
125.
126.
Stable O and C isotope data of 110 Upper Pliensbachian-Lower Bajocian belemnites have been obtained and used to attempt a reconstruction of palaeotemperature and its variation in two epicontinental depositional environments from the Western Balkan mountains (Bulgaria). The samples were collected from 3 sections with high-resolution ammonite subdivision. Initially taphonomic, cathodoluminescence and geochemical analyses were used for evidence of diagenetic alteration. Non-luminescent parts of the belemnite rostra have been sampled for isotope analyses and 76 samples, having δ18O < −4‰ (PDB), δ13C > −0.5‰ (PDB), Fe < 250 ppm, Mn < 50 ppm, Sr > 950 ppm and Sr/Mn ratio > 80 were used for palaeotemperature interpretations. The O and C isotope data generally exhibit little stratigraphical variability with minor fluctuations, however, there are prominent positive C isotope excursions and coeval negative O isotope shifts detected in the Lower Toarcian Tenuicostatum, Falciferum and Bifrons Zones. The O isotope data, interpreted in terms of palaeotemperature, revealed relatively high seawater temperatures during the Toarcian, Aalenian and Early Bajocian, with detectable temperature rises during the Early Toarcian (maximum value of 29.6 °C). Both C isotope maxima and O isotope minima are used as evidence of the Early Toarcian anoxic event reported from many localities of the same age and in similar facies in Western Europe. In the study the latter is recognized as 3 episodes, which are closely related with the seawater temperature maxima. This isotope record pattern is considered as a consequence of a global Tethyan transgression during the Early Toarcian. 相似文献
127.
Francisco?J.?MoralEmail author Elena?Pulido Antonio?Ruíz Fernando?López 《Theoretical and Applied Climatology》2017,129(3-4):881-889
The present work reports on a methodology to assess the climatic severity of a particular geographic region as compared to specific information available in the current regulations. The viability for each of the 387 municipalities in the Autonomous Community of Extremadura (Spain) is analysed, making a distinction between those with reliable climate reports and those for which no such information is available. In the case study, although the weather conditions in Extremadura are quite homogeneous according to the Spanish Technical Building Code (STBC 2015) classification and most areas are associated to zone C4 (soft winters and hot summers), the southern area in the region is associated to zone D1, similar to the north of Spain, where winters and summers are cool, which does not coincide with the actual climate in the south of Extremadura. The general climatic homogeneity in Extremadura was also highlighted with the new procedure, predominating zone C4, but unexpected or unreal climatic zoning was not generated, giving place to a consistent spatial distribution of zones throughout the region. Consequently, the proposed method allows a more accurate climatic zoning of any region in agreement with the Spanish legislation on energy efficiency in buildings, which would enhance the setting of thermal demand rates according to the actual climatic characterisation of the area in which a particular municipality is located. 相似文献
128.
129.
130.
Diel feeding of the transparent goby Aphia minuta (Pisces,Gobiidae) in the Northwestern Adriatic Sea in spring time 下载免费PDF全文
Valentina Tirelli Sara Legovini Diego Borme Elena Di Poi Mario La Mesa 《Marine Ecology》2016,37(4):920-926
The present study provides the first estimate of the daily ration for a goby species in the Mediterranean Sea, using a new approach to determine the mass of fish stomach contents through the sum of individual prey dry mass derived indirectly from prey size. Diel feeding activity and daily ration of the pelagic goby Aphia minuta were studied under natural conditions in the coastal waters off Comacchio (Northwestern Adriatic Sea) during the spring season. A total of 318 individuals of A. minuta, collected by 14 trawls carried out on 4 consecutive days, was examined for gut contents. The diel pattern of the vacuity index and the stomach fullness index indicated that A. minuta has nocturnal feeding behaviour. The daily ration, computed over a period of 16 h, was equivalent to 2.23% wet body mass. 相似文献