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1.
Caterina RINAUDO Daniela GASTALDI Orfeo ZERBINATI Elisa FORNERO Graziella BERTA 《《地质学报》英文版》2009,83(6):1224-1231
Abstract: Twenty-four soil samples were collected at three depths from an approximately 2.5 acre contaminated site in southern Piedmont (Italy) and then analyzed. The main soil parameters determined were: pH, Cation Exchange Capacity (CEC), particle size distribution, total organic carbon (TOC) content and retained metal concentration. The mineral phases were identified by X-Ray Powder Diffraction (XRPD). All of the samples contained Zn and Cu resulting from industrial contamination during the last century, and those obtained at depths of 20-40 cm consistently showed the highest levels. To determine which size fraction was most active in the retention process, the samples were separated into four fractions (≤2 mm, ≤63 μm, ≤30 μm and ≤2 μm) and the amount of pollutant measured in each. It was found that metal retention was the highest in the clayey fraction, whose clay minerals were identified by XRPD after K+ and Mg2+ saturation, glycerol treatment and heating to 550°C. The clayey fraction was also the richest in TOC, and a direct correlation between TOC amount and metal retention was observed. 相似文献
2.
Simone Dell��Agnello Caterina Lops Giovanni O. Delle Monache Douglas G. Currie Manuele Martini Roberto Vittori Angioletta Coradini Cesare Dionisio Marco Garattini Alessandro Boni Claudio Cantone Riccardo March Giovanni Bellettini Roberto Tauraso Mauro Maiello Luca Porcelli Simone Berardi Nicola Intaglietta 《Experimental Astronomy》2011,32(1):19-35
MAGIA is a mission approved by the Italian Space Agency (ASI) for Phase A study. Using a single large-diameter laser retroreflector, a large laser retroreflector array and an atomic clock onboard MAGIA we propose to perform several fundamental physics and absolute positioning metrology experiments: VESPUCCI, an improved test of the gravitational redshift in the Earth?CMoon system predicted by General Relativity; MoonLIGHT-P, a precursor test of a second generation Lunar Laser Ranging (LLR) payload for precision gravity and lunar science measurements under development for NASA, ASI and robotic missions of the proposed International Lunar Network (ILN); Selenocenter (the center of mass of the Moon), the determination of the position of the Moon center of mass with respect to the International Terrestrial Reference Frame/System (ITRF/ITRS); this will be compared to the one from Apollo and Lunokhod retroreflectors on the surface; MapRef, the absolute referencing of MAGIA??s lunar altimetry, gravity and geochemical maps with respect to the ITRF/ITRS. The absolute positioning of MAGIA will be achieved thanks to: (1) the laboratory characterization of the retroreflector performance at INFN-LNF; (2) the precision tracking by the International Laser Ranging Service (ILRS), which gives two fundamental contributions to the ITRF/ITRS, i.e. the metrological definition of the geocenter (the Earth center of mass) and of the scale of length; (3) the radio science and accelerometer payloads; (4) support by the ASI Space Geodesy Center in Matera, Italy. Future ILN geodetic nodes equipped with MoonLIGHT and the Apollo/Lunokhod retroreflectors will become the first realization of the International Moon Reference Frame (IMRF), the lunar analog of the ITRF. 相似文献
3.
Negulescu Caterina Benaïchouche Abed Lemoine Anne Le Roy Sylvestre Pedreros Rodrigo 《Natural Hazards》2020,104(1):753-793
Natural Hazards - The 2011 Great East Japan earthquake and tsunami remind us once again that these types of cascade event can occur and cause considerable damage. The scientific community realizes... 相似文献
4.
A selected assortment of Archaic‐Hellenistic tableware samples from Solunto, a Phoenician‐Punic site located 20 km east of Palermo (Sicily), has been subjected to thin‐section petrography and chemical analysis (XRF). In this settlement several ceramic kilns remained operative over a long time period (7th to 3rd century B.C.). The main goal of this analytical study is to distinguish the ceramics manufactured locally from regional and off‐island imports. Analytical results were matched to similar data concerning local natural clay sources and to coeval tableware productions from other sites in the same area. The ceramic pastes used by the ancient craftsmen of Solunto in the case of this class of pottery could be differentiated clearly by their petrochemical characteristics. We conclude that ceramics were locally produced far beyond satisfying just internal consumption needs, indicating interaction of Solunto with neighboring Greek colonies, indigenous people, and Phoenician‐Punic colonies of Sicily. © 2009 Wiley Periodicals, Inc. 相似文献
5.
This paper describes the results of an experimental, as well as theoretical, analysis of a landslide in a clay slope at the
margin of a small town of Southern Italy, whose reactivation of 1998 caused severe damages to some structures. To protect
the upslope urban area, an anchored diaphragm wall and a drainage system were constructed in 2001. In the meantime, in order
to understand the processes which caused the reactivation, a Department of the Basilicata Administrative Region provided financial
support to a geotechnical investigation. Laboratory tests on undisturbed and reconstituted specimens, in situ pore pressure
and deep displacement measurements were carried out. Both experimental and theoretical in situ water content (and porosity)
profiles were determined. Theoretical analyses of pore pressure distribution and stability analyses were carried out. The
influence of the drainage system on the slope safety factor was evaluated. Experimental and theoretical data suggest that
a first time process occurred in the lower part of the landslide system. The upper part moved on pre-existing surfaces on
which an average shear strength close to the residual strength was available. Noticeable water content increase was found
around some of these surfaces. Erosion at the toe of the landslide was the probable cause of reactivation. The analysis of
the drain system effectiveness suggests that drainage has not significantly influenced pore pressures on the considered slip
surfaces yet, mainly because of the very low permeability of the clay. 相似文献
6.
Risk-targeted seismic design maps for mainland France 总被引:3,自引:2,他引:1
In this article, the recently proposed approach known as ‘risk targeting’ for the development of national seismic design maps is investigated for mainland France. Risk targeting leads to ground-motion maps that, if used for design purposes, would lead to a uniform level of risk nationally. The Eurocode 8 design loads currently in force for France are used as the basis of this study. Because risk targeting requires various choices on, for example, the level of acceptable risk to be made a priori and these choices are not solely engineering decisions but involve input from decision makers we undertake sensitivity tests to study their influence. It is found that, in contrast to applications of this methodology for US cities, risk targeting does not lead to large modifications with respect to the national seismic hazard map nor to changes in the relative ranking of cities with respect to their design ground motions. This is because the hazard curves for French cities are almost parallel. In addition, we find that using a target annual collapse probability of about 10?5 for seismically designed buildings and a probability of collapse when subjected to the design PGA of 10?5 leads to reasonable results. This is again in contrast to US studies that have adopted much higher values for both these probabilities. 相似文献
7.
Flood-prone areas assessment using linear binary classifiers based on flood maps obtained from 1D and 2D hydraulic models 总被引:3,自引:0,他引:3
8.
Coupling of early diagenetic processes and sedimentary dynamics in tropical shelf environments: the Gulf of Papua deltaic complex 总被引:2,自引:0,他引:2
Robert. C. Aller Angelos Hannides Christina Heilbrun Caterina Panzeca. 《Continental Shelf Research》2004,24(19):2455
Tropical mobile mud belts represent a major class of biogeochemical and diagenetic systems characterized by extensive and frequent physical reworking of fine-grained, organic-rich deposits underlying oxygenated waters. Large regions of the Gulf of Papua, Papua New Guinea deltaic complex are dominated by such conditions. A reworked mud belt lies within the inner shelf between 10 and 20 m depth on a sedimentary clinoform derived from coalescing deltas. Deposits across the topset are typically suboxic, nonsulfidic over the upper 0.5–1 m, and have low to moderate maximum pore water concentrations of dissolved Fe(II) and Mn(II) (100–200, but up to 800 μM). Sediments are reactive, with surficial ΣCO2 production 0.1–0.3 mM d−1 and benthic O2 fluxes 23±15 mmol m−2 d−1 (upper 20 cm). The highest rates occur within inner topset deposits (10–20 m) and near the high accumulation rollover region of the topset–foreset beds (40–50 m). Lower rates are found inshore along intertidal channels—mangrove fringe and within scoured or exposed consolidated deposits of the middle topset region. Remineralization rate patterns are independent of relative dominance by terrestrial or marine carbon in sediments. Dissolved O2 usually penetrates 2–5 mm into surface sediments when macrofaunal burrows are absent. More than 75% of the highly reactive sedimentary Fe(III) pool (350–400 μmol g−1) is typically diagenetically reduced in the upper 0.5 m. Pore water can be measureably depleted at depths >0.5 m, but dissolved H2S generally remains below detection over the upper 1–2 m. As in other deltaic topset regions, concentration gradients often indicate that compared to many marine deposits of similar sediment accumulation rates, relatively refractory Corg is supplied to the SO4 reducing zone. Sedimentary C/S ratios are 4–6 within the suboxic topset regions but decrease to <3 in offshore foreset beds where sulfidic diagenesis dominates. Only 15–20% of the diagenetically reduced Fe(II) is pyritic and a maximum of 10–25% is carbonate, implying that most Fe(II) is associated with authigenic or lithogenic silicates or oxides. The dominance of suboxic, nonsulfidic diagenetic processes reflect coupling between delivery of oxide-rich terrestrial debris, remobilization and reoxidation of deposits, and repetitive entrainment/remineralization of both labile and refractory organics. Distinct sedimentary indicators of reactive, suboxic mobile mud belts within tropical climatic zones are: abundant total highly reactive Fe (ΣFeR )>300 μmol g−1; most reactive Fe is diagenetically reduced (ΣFe(II)/ΣFeR0.7–0.8); the proportion of diagenetically reduced Fe present as pyrite is low (Py–Fe(II)<0.2); C/S 4–8; and Corg/particle surface area <0.4 (mg C m−2). These depositional environments must be most common in tropical climates during high sea stand. 相似文献
9.
Usman T. Khan Caterina Valeo Jianxun He 《Stochastic Environmental Research and Risk Assessment (SERRA)》2013,27(3):599-616
In this paper, a new non-linear fuzzy-set based methodology is proposed to characterize and propagate uncertainty through a multiple linear regression (MLR) model to predict DO using flow and water temperature as the regressors. The output is depicted as probabilistic rather than deterministic and is used to calculate the risk of low DO concentration. To demonstrate the new method, data from the Bow River in Calgary, Alberta from 2006 to 2008 are used. Low DO concentration has been occasionally observed in the river and correctly predicting, and quantifying the associated uncertainty and variability of DO is of interest to the City of Calgary. Flow, temperature and DO data were used to construct five MLR models, using different combinations of linear and non-linear fuzzy membership functions. The results show that non-linear representation of variance is superior to the linear approach based on model performance. Normal and Gumbel based membership functions produced the best results. The outputs from two non-linear fuzzy membership models were used to calculate risk of low DO. The predicted risk was between 3.9 and 4.9 %. This is an improvement over the traditional method, which can not indicate a risk of low DO for the same time period. This study demonstrates that water resource managers can adequately use MLR models to predict the risk of low DO using abiotic factors. 相似文献
10.
M. Cristina Fossi Letizia Marsili Giancarlo Lauriano Caterina Fortuna Simone Canese Stefania Ancora Claudio Leonzio Teresa Romeo Ruben Merino Esteban Abad Begoa Jimnez 《Marine environmental research》2004,58(2-5):269
Various studies have revealed high concentrations of contaminants such as organochlorines (OCs) and heavy metals in Mediterranean cetaceans. A geographical trend of contamination (PCBs and DDTs) has been found for striped dolphin (Stenella coeruleoalba). In this study we used a non-lethal approach (skin biopsy) to investigate bioaccumulation of OCs, including polychlorobiphenyls (PCBs), DDTs, polychlorodibenzo-p-dioxins (PCDDs), polychlorodibenzofurans (PCDFs), trace elements (Hg, Cd, Pb) and CYP1A activity (BPMO) in nine striped dolphins sampled in the Aeolian area (Sicily – Italy) in summer 2002. The arithmetic mean value of BPMO activity in this group was 43.46 AUF/g tissue/h. This value is approximately 3 times and 5 times lower, respectively, than the value found in the Ionian and in the Ligurian groups. Skin biopsies of striped dolphins emerged as a suitable material for assessing the toxicological status of the various Mediterranean groups. 相似文献