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Izaskun Jiménez-Serra Jesús Martín-Pintado Arturo Rodríguez-Franco Paola Caselli Serena Viti Tom Hartquist 《Astrophysics and Space Science》2008,313(1-3):159-163
We present the first C-shock and radiative transfer model that calculates the evolution of the line profiles of neutral and
ion species like SiO, H13CO+ and HN13C for different flow times along the propagation of the shock through the unperturbed gas. We find that the line profiles
of SiO characteristic of the magnetic precursor stage have very narrow linewidths and are centered at velocities close to
the ambient cloud velocity, as observed toward the young shocks in the L1448-mm outflow. Consistently with previous works,
our model also reproduces the broad SiO emission detected in the high velocity gas in this outflow, for the downstream postshock
gas in the shock. This implies that the different velocity components observed in L1448-mm are due to the coexistence of different
shocks at different evolutionary stages. 相似文献
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Ammonites are extinct molluscs belonging to Class Cephalopoda which lived during the Mesozoic Era. Their usefulness in Jurassic and Cretaceous paleontology and biostratigraphy studies has been widely proved. They have been studied by several authors worldwide to achieve information regarding their habitats and the climate of the world in past eras. A probabilistic analysis of the paleo-environmental causes that generated complex suture lines in ammonites has been made by means of coherent upper conditional previsions defined with respect to Hausdorff outer measures. In particular, studies have centered on the role of hydrostatic pressure. 相似文献
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David A Williams and Serena Viti survey the contributions made to this fast-moving field at a recent RAS Discussion Meeting. The resulting debates were often both challenging and confrontational. 相似文献
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Delphine Bonnet Anthony Richardson Andrew Hirst Martin Edwards Rabea Diekman Luis Valdes Juan Carlos Molinero Wulf Greve Aitor Albaina Serena Fonda Umani Antonina dos Santos Susan Robinson 《Progress in Oceanography》2005,65(1):1-53
We review current knowledge and understanding of the biology and ecology of the calanoid copepod Calanus helgolandicus in European waters, as well as provide a collaborative synthesis of data from 18 laboratories and 26 sampling stations in areas distributed from the northern North Sea to the Aegean and Levantine Seas. This network of zooplankton time-series stations has enabled us to collect and synthesise seasonal and multi-annual data on abundance, body size, fecundity, hatching success and vertical distribution of C. helgolandicus. An aim was to enable comparison with its congener Calanus finmarchicus, which has been studied intensively as a key component of European and north east Atlantic marine ecosystems. C. finmarchicus is known to over-winter at depth, whereas the life-cycle of C. helgolandicus is less well understood. Overwintering populations of C. helgolandicus have been observed off the Atlantic coast between 400 and 800 m, while in the Mediterranean there is evidence of significant deep-water populations at depths as great as 4200 m. The biogeographical distribution of C. helgolandicus in European coastal waters covers a wide range of habitats, from open ocean to coastal environments, and its contribution to mesozooplankton biomass ranges from 6% to 93%. Highest abundances were recorded in the Adriatic and off the west coast of Spain. C. helgolandicus is generally found in 9-20 °C water, with maximum abundances from 13-17 °C. In contrast, C. finmarchicus is found in cooler water between 0 and 15 °C, with peak abundances from 0 to 9 °C. As water has warmed in the North Atlantic over recent decades, the range of C. helgolandicus and its abundance on the fringes of its expanding range have increased. This review will facilitate development of population models of C. helgolandicus. This will not only help answer remaining questions but will improve our ability to forecast future changes, in response to a warming climate, in the abundance and distribution of this important species. 相似文献
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Bulletin of Earthquake Engineering - Seismic modelling of unreinforced masonry (URM) buildings is addressed worldwide according to different approaches, not only at research level, but also in the... 相似文献
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Ottonelli Daria Manzini Carlo Filippo Marano Corrado Cordasco Emilia Angela Cattari Serena 《Bulletin of Earthquake Engineering》2022,20(4):2115-2158
Bulletin of Earthquake Engineering - The paper presents the comparison of the results of nonlinear static analyses carried out using six software packages (SWs) available at professional level and... 相似文献