The recycling of gas and metals in galaxy formation: predictions of a dynamical feedback model     

Serena Bertone  Gabriella De Lucia  Peter A. Thomas 《Monthly notices of the Royal Astronomical Society》2007,379(3):1143-1154

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Metal speciation and environmental impact on sandy beaches due to El Salvador copper mine, Chile   总被引：1，自引：0，他引：1  

Ramirez M  Massolo S  Frache R  Correa JA 《Marine pollution bulletin》2005,50(1):62-72

Several coastal rocky shores in northern Chile have been affected by the discharges of copper mine tailings. The present study aims to analyze the chemical speciation of heavy metals in relation to the diversity of sessile species in the rocky intertidal benthic community on the northern Chilean coast, which is influenced by the presence of copper mine tailings. In particular, the chemical forms of Cd, Cu, Fe, Mn, Ni, Pb and Zn in beach sediment samples collected in the area influenced by El Salvador mine tailings were studied using a sequential chemical extraction method. In general, all the elements present a maximum concentration in the area near the actual discharge point (Caleta Palito). With regard to Cu and Mn, the concentrations range between 7.2-985 and 746-22,739 microg/g respectively, being lower than background levels only in the control site of Caleta Zenteno. Moreover, the correlation coefficients highlight that Fe, Mn and Ni correlate significantly and positively in the studied area, showing a possible common, natural origin, whilst Cu shows a negative correlation with Fe, Mn and Ni. It could be possible that Cu has an anthropogenic origin, coming from mining activity in the area. Cd, Fe, Mn, Ni, Pb and Zn are mostly associated with the residual phase, whilst Cu presents a different speciation pattern, as resulted from selective extractions. In fact, Cu is highly associated with organic and exchangeable phases in contaminated localities, whilst it is mainly bound to the residual phase in control sites. Moreover, our results, compared to local biological diversity, showed that those sites characterized by the highest metal concentrations in bioavailable phase had the lowest biodiversity.  相似文献   

PCDD and PCDF intake through consumption of locally produced seafood by Venice lagoon residents: elements for risk management     

Miniero R  Ceretti G  Cherin E  Dellatte E  De Luca S  Ferri F  Fulgenzi AR  Grim F  Iacovella N  Iamiceli AL  Ingelido AM  Vio P  di Domenico A 《Marine pollution bulletin》2005,50(12):1727-1732

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Impact controversies: Impact recognition criteria and related issues     

Wolf Uwe Reimold  Ludovic Ferrière  Alex Deutsch  Christian Koeberl 《Meteoritics & planetary science》2014,49(5):723-731

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Revisiting the Rochechouart impact structure,France     

Haley M. Sapers  Gordon R. Osinski  Neil R. Banerjee  Ludovic Ferrière  Philippe Lambert  Matthew R. M. Izawa 《Meteoritics & planetary science》2014,49(12):2152-2168

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The metallicity of CM Draconis     

Serena Viti  Hugh R. A. Jones  Pierre Maxted  Jonathan Tennyson 《Monthly notices of the Royal Astronomical Society》2002,329(2):290-300

We compare observations of the eclipsing binary system CM Draconis (hereafter CM Dra) with synthetic spectra computed using the stellar atmosphere code phoenix . High-resolution infrared spectroscopic observations of six 0.05-μm-wide regions between 1.51 and 2.45 μm, combined with previous work, particularly CM Dra's accurately known surface gravity, enable us to estimate its metallicity using detailed spectral synthesis. We find significant discrepancies between the observed and synthetic spectra throughout most of the region emphasizing the need for higher quality atomic data in the infrared. Nevertheless, the     CO bands beyond 2.3 μm seem to be well modelled and metal-sensitive, and thus high-resolution spectra should be a most powerful diagnostic tool for spectroscopic analyses for M dwarfs and brown dwarfs. The CO bands indicate a metallicity of around −1 dex for CM Dra. This result is supported by observations of two M dwarfs of similar spectral type, GJ 699 (Barnard's star) and GJ 725B. This result supports inferences from previous infrared work, although it does not agree with standard evolutionary models or optical analyses, which both suggest an abundance for CM Dra close to that of the Sun.  相似文献   

Correction to: Benchmarking the software packages to model and assess the seismic response of unreinforced masonry existing buildings through nonlinear static analyses     

Cattari  Serena  Magenes  Guido 《Bulletin of Earthquake Engineering》2022,20(4):1937-1937

Bulletin of Earthquake Engineering - A correction to this paper has been published: https://doi.org/10.1007/s10518-021-01105-0  相似文献   

WIP: A Web‐based program for indexing planar features in quartz grains and its usage          下载免费PDF全文

Anna Losiak  Izabela Golebiowska  Ludovic Ferrière  Jacek Wojciechowski  Matthew S. Huber  Christian Koeberl 《Meteoritics & planetary science》2016,51(4):647-662

Planar deformation features (PDFs) in quartz are the most important diagnostic features that allow the unambiguous identification of impact structures on Earth. In order to confirm that these features (that are characterized by planar character and form along specific crystallographic planes) are indeed PDFs, they need to be properly investigated and indexed. Following universal‐stage measurements, the process of indexing is usually performed manually, using a Wulff stereonet and following a strict procedure, which is time consuming and error prone. In this article, we present WIP, a new Web‐based program for indexing planar deformation features in quartz. The correctness of our program is shown by its application to measurements that had previously been indexed manually. The observed minor differences, especially in the absolute frequency percentage of PDFs, are negligible and not significant enough to influence the estimation of shock pressure that could be calculated from the indexed results. Usability of this program is shown using the spatial relationships between a statistically significant number of 278 quartz grains with 409 sets of PDFs analyzed within the area (~35 mm²) of a single thin section of a meta‐greywacke from the Bosumtwi impact structure. Our program is not only more accurate and faster than the manual (graphical) method but also removes the human error from the plotting process and allows control of several parameters, such as the value of estimated measurement error used in the indexing calculation or method of aggregated error handling. The program also provides information about the angles between the planes of the measured PDF sets present in a grain, which allows determination of the angles between (for example) indexed {} and {} sets.  相似文献   

Landslides types controlled by tectonics-induced evolution of valley slopes (Northern Apennines,Italy)     

Mirko Carlini  Alessandro Chelli  Roberto Francese  Serena Giacomelli  Massimo Giorgi  Andrea Quagliarini  Andrea Carpena  Claudio Tellini 《Landslides》2018,15(2):283-296

This paper investigates the role played by geomorphological and tectonic processes affecting a portion of an active mountain belt in causing the occurrence of different types of landslides developed in flysch bedrock. The adopted multidisciplinary approach (geomorphology, geology and geophysics) allowed to recognize in a portion of the Northern Apennines of Italy different types of landslides that developed in response to slope dynamics, in turn dependent on broader regional-scale tectonic processes. Sedimentary bed attitude, local tectonic discontinuities and lithology only partially influenced the type of landslides, which have been deeply affected by the activity of regional-scale antiform that controlled the hillslope geomorphic evolution in different ways. The growth of this structure and the tilting of its forelimb produced gently dipping slopes that approached the threshold angle that can cause the occurrence of (mainly) translational rockslides. Conversely, high-angle normal faulting parallel to the antiform axis (related to a later stage of activity of the antiform itself) strongly controlled the stream network evolution and caused the watercourses to deeply incise portions of their valleys. This incision produced younger steep valley slopes and caused the development of complex landslides (roto-translational slides-earth/debris flow). The results of the integrated study presented in this paper allowed to distinguish two main types of landslides whose development reflects the events that led to the geomorphological and geological evolution of the area. In this perspective, within the study area, landslides can be regarded and used as indicators of broader-scale recent tectonic processes.  相似文献   

Annual and spatial variations of chemical and physical properties in the Ross Sea surface waters (Antarctica)     

Serena Massolo  Roberta Messa  Paola Rivaro  Riccardo Leardi 《Continental Shelf Research》2009

Temperature, salinity, meltwater percentage, water column stability, dissolved oxygen and nutrients were measured in seawater samples collected at three fixed depths (0, 20, 100 m) in 104 stations located in three different areas of the Ross Sea (Antarctica), during four Italian Antarctic surveys carried out between 1998 and 2006. Nutrient data were used to quantify the nutrient removal, which appears particularly high in 2006, especially in polynya area. The N:P and Si:N disappearance ratios were studied to estimate the dominant phytoplanktonic community. No significant differences in the nutrient drawdown ratio were observed, in fact the N:P ratio was always below the Redfield standard ratio.  相似文献