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61.
62.
Janet E. Drew R. Greimel M. J. Irwin A. Aungwerojwit M. J. Barlow R. L. M. Corradi J. J. Drake B. T. Gänsicke P. Groot A. Hales E. C. Hopewell J. Irwin C. Knigge P. Leisy D. J. Lennon A. Mampaso M. R. W. Masheder M. Matsuura L. Morales-Rueda R. A. H. Morris Q. A. Parker S. Phillipps P. Rodriguez-Gil G. Roelofs I. Skillen J. L. Sokoloski D. Steeghs Y. C. Unruh K. Viironen J. S. Vink N. A. Walton A. Witham N. Wright A. A. Zijlstra A. Zurita 《Monthly notices of the Royal Astronomical Society》2005,362(3):753-776
63.
LaForce Tara Ebeida Mohamed Jordan Spencer Miller Terry A. Stauffer Philip H. Park Heeho Leone Rosie Hammond Glenn 《Mathematical Geosciences》2023,55(2):129-161
Mathematical Geosciences - Mesh generation lies at the interface of geological modeling and reservoir simulation. Highly skewed or very small grid cells may be necessary to accurately capture the... 相似文献
64.
S. Covino E. Molinari P. Bruno M. Cecconi P. Conconi P. D'Avanzo L. di Fabrizio D. Fugazza M. Giarrusso E. Giro F. Leone V. Lorenzi S. Scuderi 《Astronomische Nachrichten》2014,335(2):117-123
We describe a new polarimetric facility available at the Istituto Nazionale di AstroFisica / Telescopio Nazionale Galileo at La Palma, Canary islands. This facility, PAOLO (Polarimetric Add‐On for the LRS Optics), is located at a Nasmyth focus of an alt‐az telescope and requires a specific modeling in order to remove the time‐ and pointing position‐dependent instrumental polarization. We also describe the opto‐mechanical structure of the instrument and its calibration and present early examples of applications. (© 2014 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
65.
Michele Lustrino Leone Melluso Vincenzo Morra 《Earth and Planetary Science Letters》2000,180(3-4):259-270
The first comprehensive chemical and Sr–Nd–Pb isotopic data set of Plio–Pleistocene tholeiitic and alkaline volcanic rocks cropping out in Sardinia (Italy) is presented here. These rocks are alkali basalts, hawaiites, basanites, tholeiitic basalts and basaltic andesites, and were divided into two groups with distinct isotopic compositions. The vast majority of lavas have relatively high 87Sr/86Sr (0.7043–0.7051), low 143Nd/144Nd (0.5124–0.5126), and are characterised by the least radiogenic Pb isotopic composition so far recorded in Italian (and European) Neogene-to-Recent mafic volcanic rocks (206Pb/204Pb=17.55–18.01) (unradiogenic Pb volcanic rocks, UPV); these rocks crop out in central and northern Sardinia. Lavas of more limited areal extent have chemical and Sr–Nd–Pb isotopic ratios indicative of a markedly different source (87Sr/86Sr=0.7031–0.7040; 143Nd/144Nd=0.5127–0.5129; 206Pb/204Pb=18.8–19.4) (radiogenic Pb volcanic rocks, RPV), and crop out only in the southern part of the island. The isotopic ratios of these latter rocks match the values found in the roughly coeval anorogenic (i.e. not related to recent subduction events in space and time) mafic volcanic rocks of Italy (i.e. Mt. Etna, Hyblean Mts., Pantelleria, Linosa), and Cenozoic European volcanic rocks. The mafic rocks of the two Sardinian rock groups also show distinct trace element contents and ratios (e.g. Ba/Nb>14, Ce/Pb=8–25 and Nb/U=29–38 for the UPV; Ba/Nb<9, Ce/Pb=24–28 and Nb/U=46–54 for the RPV). The sources of the UPV could have been stabilised in the Precambrian after low amounts of lower crustal input (about 3%), or later, during the Hercynian Orogeny, after input of Precambrian lower crust in the source region, whereas the sources of the RPV could be related to processes that occurred in the late Palaeozoic–early Mesozoic, possibly via recycling of proto-Tethys oceanic lithosphere by subduction. 相似文献
66.
As part of the environmental recovery plan for the Mar Piccolo (Ionian Sea), a basin suffering especially from urban pollution, a study was planned on the modifications induced by the human activities to distinguish them from those due to the alternation of the seasons and the exchanges with the neighbouring basin of Mar Grande. The present paper deals with the chemical-physical characteristics of sea water and its particulate matter content is investigated as a part of this study. The physical, chemical and biological variables (stochastic variables for the model) are: chlorophyll a, proteins, carbohydrates, organic matter, dry weight, temperature, salinity, dissolved oxygen, pH, ultraviolet absorbance, phosphate, nitrite, nitrate, ammonia, silicate, photosynthetically available radiation (PAR) and energy. These variables have been sampled at 15 different stations during one year of monthly sampling. A preliminary analysis was carried out on the variables for detecting possible interactions among all the investigated parameters. To this purpose, and for all the variables, an original computer program for non-parametric statistical-evaluation and data-correlation was used to find correlation-guided hierarchy of variables. The relations among: Prot and Chl-a, Carb and Chl-a and OM and DW have been studied. The slopes of linear regression of (Prot, Chl-a) and (Carb, Chl-a) allowed us to detect different relations at different space-time areas. A nonlinear relation between OM and DW has been found as well. This treatment is a first approach to the construction of a mathematical model of the basin. Different areas, for sea water characteristics, were observed to occur in the basin, despite its small extension. This may be due to the reduced water exchanges and the different residential development along the coast. Innermost areas, less involved in the water mass circulation, were more affected by eutrophication. 相似文献
67.
Marvin Lanphere Duane Champion Leone Melluso Vincenzo Morra Annamaria Perrotta Claudio Scarpati Dario Tedesco Andrew Calvert 《Bulletin of Volcanology》2007,69(3):259-263
The Italian volcano, Vesuvius, erupted explosively in AD 79. Sanidine from pumice collected at Casti Amanti in Pompeii and Villa Poppea in Oplontis yielded a weighted-mean 40Ar/39Ar age of 1925±66 years in 2004 (1σ uncertainty) from incremental-heating experiments of eight aliquants of sanidine. This is the calendar age of the eruption. Our results together with the work of Renne et al. (1997) and Renne and Min (1998) demonstrate the validity of the 40Ar/39Ar method to reconstruct the recent eruptive history of young, active volcanoes. 相似文献
68.
Romano L. M. Corradi Regina Aznar & Antonio Mampaso 《Monthly notices of the Royal Astronomical Society》1998,297(2):617-623
Narrow-band CCD images of 209 axially symmetrical planetary nebulae (PNe) have been examined in order to determine the orientation of their axes within the disc of the Galaxy. The nebulae have been divided into the bipolar (B) and elliptical (E) PNe morphological types, according to the scheme of Corradi &38; Schwarz. In both classes, contrary to the results of Melnick &38; Harwit and Phillips we do not find any strong evidence for non-random orientations of the nebulae in the Galaxy. Compared with previous work in this field, the present study takes advantage of the use of larger and morphologically more homogeneous samples and offers a more rigorous statistical analysis. 相似文献
69.
G. Cortecci A. Del Moro G. Leone G. C. Pardini 《Contributions to Mineralogy and Petrology》1979,68(4):421-427
Rock samples from the lithologic units forming the Adamello massif were analyzed for Rb and Sr concentrations and for87Sr/86Sr and18O/16O ratios. The most important features are as follows:
- the strontium and oxygen isotopes show a systematic variation from south to northwest across the massif, the older units in the south being lower both in87Sr and18O;
- a good positive correlation was found between strontium and oxygen isotopic compositions.
70.
Land cover and land use change in the Italian central Apennines: A comparison of assessment methods 总被引:1,自引:0,他引:1
Raffaele Pelorosso Antonio Leone Lorenzo Boccia 《Applied geography (Sevenoaks, England)》2009,29(1):35-48
Analyses of land-use cover changes (LUCC) are fundamental to the understanding of numerous social, economical and environmental problems and can be carried out rapidly, using either cartographic or census data. However, the trends of the two methods differ in direction and quantity.For this study, a historical and a recent remote sensing-derived map were homogenized to reduce misleading changes and to assess spatial aggregation errors. This was carried out by means of a data integration procedure based on landscape metrics, allowing cartographic and census trends to be compared. Discrepancies between data were thus highlighted, both in absolute surface value and in evolution.The methodology presented, and the results obtained, could be employed to evaluate and improve LUCC analyses aimed at assessing landscape identity, both in the case of analyses based only on LU census data, or of those based only on LC cartographic data. This could lead to benefits for both biodiversity conservation and environmental planning on a large scale. 相似文献