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91.
Fabrizio Murgia Riccardo Biddau Alessandro Concas Roberto Demontis Luca Fanfani Zeno Heilmann Cristian Lai Giuditta Lecca Eva Lorrai Marino Marrocu Vittorio Alessandro Marrone Laura Muscas Elisaveta Peneva Andrea Piras Massimo Pisu Gabriella Pusceddu Guido Satta Daniela Theis Andrea Vacca Paolo Valera Ana Melina Vallenilla Ferrara Ernesto Bonomi 《Earth Science Informatics》2009,2(1-2):5-21
GRIDA3 (Shared Resources Manager for Environmental Data Analysis and Applications) is a multidisciplinary project designed to deliver an integrated system to forge solutions to some environmental challenges such as the constant increase of polluted sites, the sustainability of natural resources usage and the forecast of extreme meteorological events. The GRIDA3 portal is mainly based on Web 2.0 technologies and EnginFrame framework. The portal, now at an advanced stage of development, provides end-users with intuitive Web-interfaces and tools that simplify job submission to the underneath computing resources. The framework manages the user authentication and authorization, then controls the action and job execution into the grid computing environment, collects the results and transforms them into an useful format on the client side. The GRIDA3 Portal framework will provide a problem-solving platform allowing, through appropriate access policies, the integration and the sharing of skills, resources and tools located at multiple sites across federated domains. 相似文献
92.
Rosati P. Basa S. Blain A. W. Bozzo E. Branchesi M. Christensen L. Ferrara A. Gomboc A. O’Brien P. T. Osborne J. P. Rossi A. Schüssler F. Spurio M. Stergioulas N. Stratta G. Amati L. Casewell S. Ciolfi R. Ghirlanda G. Grimm S. Guetta D. Harms J. Le Floc’h E. Longo F. Maggiore M. Mereghetti S. Oganesyan G. Salvaterra R. Tanvir N. R. Turriziani S. Vergani S. D. Balman S. Caruana J. Erkut M. H. Guidorzi G. Frontera F. Martin-Carrillo A. Paltani S. Porquet D. Sergijenko O. 《Experimental Astronomy》2021,52(3):407-437
Experimental Astronomy - The proposed THESEUS mission will vastly expand the capabilities to monitor the high-energy sky. It will specifically exploit large samples of gamma-ray bursts to probe the... 相似文献
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Marco Murru Concetta Ferrara Stefania Da Pelo Angelo Ibba 《Comptes Rendus Geoscience》2003,335(2):227-238
The Palaeocene of southern Sardinia includes a continental ferruginous sedimentation, with a high content of Al and Fe, indicative of a subhumid tropical climate. The subsequent microcodium carbonated detrital microcodium levels, containing an abundant quartzose fraction, rather suggest semiarid conditions. In SW Sardinia, the marine deposits, referred to Late Thanetian–Lower Ypresian (=Ilerdian) times, are limestones including larger foraminifers and contain significant amounts of quartz. A lower content of detrital kaolinite points a sediment source from the surrounding areas with a semiarid climate. The occurrence, at the top of this unit, of small trochospiral rotaliids and larger amount of detrital kaolinite suggests a transition to a rainy tropical climate in the adjacent areas. These limestones pass gradually to carbonate sediments characterized by large amounts of detrital kaolinite and intercalated coal layers, with pollen of tropical palms, attributed to the Late Ypresian (=Cuisian)–Early Lutetian and referred to a humid-subhumid tropical climate. 相似文献
96.
In order to interpret H2 quasar absorption-line observations of damped Lyα systems (DLAs) and subDLAs, we model their H2 abundance as a function of dust-to-gas ratio, including H2 self-shielding and dust extinction against dissociating photons. Then, we constrain the physical state of the gas by using H2 data. Using H2 excitation data for DLAs with H2 detections, we derive a gas density 1.5 ≲ log n (cm−3 ) ≲ 2.5 , temperature 1.5 ≲ log T (K) ≲ 3 , and an internal ultraviolet (UV) radiation field (in units of the Galactic value) 0.5 ≲ log χ≲ 1.5 . We then find that the observed relation between the molecular fraction and the dust-to-gas ratio of the sample is naturally explained by the above conditions. However, it is still possible that H2 deficient DLAs and subDLAs with H2 fractions less than ∼10−6 are in a more diffuse and warmer state. The efficient photodissociation by the internal UV radiation field explains the extremely small H2 fraction (≲10−6 ) observed for κ≲ 1/30 (κ is the dust-to-gas ratio in units of the Galactic value); H2 self-shielding causes a rapid increase in, and large variations of, H2 abundance for κ≳ 1/30 . We finally propose an independent method to estimate the star formation rates of DLAs from H2 abundances; such rates are then critically compared with those derived from other proposed methods. The implications for the contribution of DLAs to the cosmic star formation history are briefly discussed. 相似文献
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Luigi Marini Valeria Chiappini Roberto Cioni G. Cortecci E. Dinelli Claudia Principe Giorgio Ferrara 《Bulletin of Volcanology》1998,60(3):187-194
Sulfur contents and δ34S values of Somma-Vesuvius magmas are consistent with syneruptive, open-system degassing at temperatures of 800–850°C for
Plinian pumices and 1100–1200°C for lavas. The extent of degassing appears to be greater in lavas than in pumices. The key
parameter controlling the 34S/32S ratio of Somma-Vesuvius volcanics is the average magma oxidation state, which generally varies from 0.85 to 1.20 Δ NNO units
for lavas and from 1.20 to 1.40 Δ NNO units for pumices. Consequently, S contents and δ34S values of magmas constitute a potentially valuable tool in estimating their average redox conditions. The results of this
study may help in risk mitigation when the Vesuvius magmatic system evolves toward eruptive conditions.
Received: 20 January 1998 / Accepted: 5 May 1998 相似文献
100.
Intercomparison of Boron Isotope and Concentration Measurements. Part II: Evaluation of Results 总被引:3,自引:1,他引:3
Roberto Gonfiantini Sonia Tonarini Manfred Grning Alessandra Adorni‐Braccesi Assad S. Al‐Ammar Marcus Astner Sebastien Bchler Ramon M. Barnes Randy L. Bassett Alain Cocherie Annette Deyhle Andrea Dini Giorgio Ferrara Jrme Gaillardet Judith Grimm Catherine Guerrot Urs Krhenbühl Graham Layne Damien Lemarchand Anette Meixner D. Jack Northington Maddalena Pennisi Eva Reitznerov Ilia Rodushkin Naoji Sugiura Regina Surberg Sabine Tonn Michael Wiedenbeck Samuel Wunderli Yingkai Xiao Thomas Zack 《Geostandards and Geoanalytical Research》2003,27(1):41-57
The Istituto di Geoscienze e Georisorse (IGG), on behalf and with the support of the International Atomic Energy Agency (IAEA), prepared eight geological materials (three natural waters and five rocks and minerals), intended for a blind interlaboratory comparison of measurements of boron isotopic composition and concentration. The materials were distributed to twenty seven laboratories - virtually all those performing geochemical boron isotope analyses in the world -which agreed to participate in the intercomparison exercise. Only fifteen laboratories, however, ultimately submitted the isotopic and/or concentration results they obtained on the intercomparison materials. The results demonstrate that interlaboratory reproducibility is not well reflected by the precision values reported by the individual laboratories and this observation holds true for both boron concentration and isotopic composition. The reasons for the discrepancies include fractionations due to the chemical matrix of materials, relative shift of the zero position on the δ11 B scale and a lack of well characterized materials for calibrating absolute boron content measurements. The intercomparison materials are now available at the IAEA (solid materials) and IGG (waters) for future distribution. 相似文献