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121.
Fabrizio Eva 《GeoJournal》1997,43(1):61-75
The past fifty years have seen several elements and factors leading to the current homogenization of Italian society: the internal migration from South to North, the development of a more and more industrial and affluent society, the increase of links with Europe/World culture and economy. Nevertheless in the last decade in Northern Italy emerged the political phenomenon of autonomist parties, in particular the most successful of them: the Lega Nord. This success happened in parallel with the loss of power by traditional government parties, also as a consequence of the trial against corruption held in Milan at the beginning of the '90. Italian politics is in turmoil and it is impossible to forecast the duration or even its end. The problem is to determine the most significant elements, and which factors have the greatest effect on the current reality, also to be able to venture a prediction regarding trends. The paper suggests some ethno-nationalism evaluation criteria, useful to assess the more or less successful geopolitical dynamics where there are separatist claims. According with those criteria the Northern Italian political situation has been briefly described and evaluated, with particular attention to electoral results of the Lega Nord party. These results show a well defined geographical distribution and hence the minority condition in the North of the separatist supporters. The actual political debate in Italy has the aim to change some parts of the Constitution in the sense of federalism; it can be a sufficient reply to secessionist claims and it can make the independence of Northern Italy unlikely. 相似文献
122.
123.
Using GB-SAR technique to monitor slow moving landslide 总被引:3,自引:0,他引:3
Linhsia Noferini Massimiliano Pieraccini Daniele Mecatti Giovanni Macaluso Carlo Atzeni Matteo Mantovani Gianluca Marcato Alessandro Pasuto Sandro Silvano Fabrizio Tagliavini 《Engineering Geology》2007,95(3-4):88-98
A Ground-Based SAR (GB-SAR) interferometer was employed to measure the surface displacements of a landslide occurring in the Carnian Alps, north-eastern Italy, which has affected a national road and seriously damaged a road tunnel still under construction. Moreover, since the landslide is located on the left bank of the Tagliamento River Valley, it is feared that this mass movement might dam the river, creating a basin that would increase natural hazard for the valley inhabitants. The data collected from December 2002 to July 2005 by a conventional monitoring system, consisting of a GPS network and boreholes equipped with inclinometric tubes, showed that the landslide was moving at a quasi-constant rate of about 3 cm per year. Due to the slow deformation rate of the landslide, a recently developed GB-SAR technique based on the analysis of a restricted ensemble of coherent points was used. Two surveys, each lasting two days, were planned in December 2004 and July 2005, in order to map and measure the surface displacements that occurred over time. The results from the radar were compared with the ones derived from the GPS monitoring network. An agreement was achieved among the data collected, showing the capability of the GB-SAR technique to measure displacements even within a time span of several months between the surveys. 相似文献
124.
The Bader topological analysis has been applied to ab initio computed electron densities of beryl, in order to clarify its
mechanism of compression. Full structural optimization and total energy (E) calculations were performed at different cell volumes (V
c). The pressure at each volume and the equation of state were estimated from the first and second derivatives of the resultant
E(V
c) curve. The total (negative) potential energy of the crystal, sum of both attractive and repulsive electrostatic terms, was
found to systematically decrease (i.e., it moved to more negative values) up to the highest pressure considered (28.4 GPa),
indicating that interelectronic and internuclear repulsions are not the only terms controlling the compressibility, at least in the pressure range investigated. Electronic kinetic energy increases
as the cell volume is reduced, leading to a parallel increase of the total energy. Both structure at equilibrium and compressibility
are therefore due to the balance between the opposing kinetic and potential energy terms. The Bader theory has been used to identify the topological atoms within the structure and to calculate their properties, with particular attention to the forces driving the structural
relaxation at high pressure. On a qualitative basis, the obtained results are expected to be transferable to the discussion
of compressibility of other mineral phases. 相似文献
125.
Fabrizio Rama Konrad Miotlinski Davide Franco Henry X. Corseuil 《Hydrogeology Journal》2018,26(6):1887-1902
A time-series approach to the estimation of recharge rate in unconfined aquifers of highly variable water level is proposed. The approach, which is based on the water-table fluctuation method (WTF), utilizes discrete water-level measurements. Other similar techniques require continuous measurements, which makes them impossible to apply in cases where no data from automatic loggers are available. The procedure is deployed at the Ressacada Farm site, southern Brazil, on a coastal shallow aquifer located in a humid subtropical climate where diurnal water-level variations of up to 1 m can follow a precipitation event. The effect of tidal fluctuations on the groundwater levels is analyzed using a harmonic component builder, while a time-variable drainage term is evaluated through an independent analysis and included in the assessment. The estimated recharge values are compared with those obtained from the continuous measurements showing a good agreement with the approaches for discrete dataset intervals of up to 15 days. Subsequently, the estimated recharge rates are incorporated into a transient groundwater-flow model and the water levels are compared showing a good match. Henceforth, the approach extends the applicability of WTF to noncontinuous water-level datasets in groundwater recharge studies. 相似文献
126.
Clémentine Perstrimaux Séverine Le Faucheur Monika Mortimer Serge Stoll Fabrizio Bernardi Aubry Margherita Botter Roberto Zonta Vera I. Slaveykova 《Aquatic Geochemistry》2015,21(2-4):343-362
The present study explores the effect of salinity and dissolved organic carbon (DOC) gradients on the stability and reactivity of titanium dioxide nanoparticle (TiO2-NP) agglomerates in ambient water from the Lagoon of Venice and their possible effect on nauplii sampled at the same locations. In all ambient water samples, TiO2-NPs formed rapidly micrometre-sized agglomerates. The increase in the salinity and concomitant decrease in DOC content induced the formation of larger agglomerates, with z-average hydrodynamic diameter increasing with TiO2-NP concentration and exposure duration. Under the studied conditions, ζ-potential exhibited negative values. In line with agglomeration results, enhancement of the salinity and lower DOC resulted in less negative ζ-potential with close to 0 values in the dispersions of 100 mg L?1 TiO2-NPs in sea water. Two-hour exposure to micrometre-sized agglomerates of TiO2-NPs resulted in an increase in the fluorescence of propidium iodide (PI) stained nauplii in comparison with unexposed controls, but had no effect at 24-h exposure. The increase in nauplii-associated PI fluorescence was more noticeable in dispersions containing 100 mg L?1 than those containing 10 mg L?1 TiO2-NPs, suggesting membrane permeability alteration in a concentration-dependent manner. However, the PI staining results have to be interpreted with caution because of the possible dye binding to the nauplii surface without penetration of cellular membrane. The effect of TiO2-NPs on nauplii was more pronounced at higher salinity and decreased with increasing DOC concentrations at 2 h, while no trends were found at 24-h exposure, as well as exposure to 100 mg L?1 TiO2-NPs. 相似文献
127.
Maximilian Huber Fabrizio Marconi Massimiliano Moscatelli 《Georisk: Assessment and Management of Risk for Engineered Systems and Geohazards》2015,9(1):49-56
The evaluation of the underground soil stratigraphy is a key aspect in geotechnical site characterisation. However, these means of site exploration are only pinholing subsoil conditions and expert knowledge is needed to understand subsoil conditions in order to build a reliable geological-geotechnical model. This contribution employs a geostatistical simulation methodology for the simulation of random fields representing geological uncertainty. This combines borehole data and expert knowledge via a mathematical framework. Moreover a risk-based site characterisation scheme is developed for urban site characterisation. This novel characterisation scheme offers additional insight into the effects of large-scale, geological spatial variability by using fragility curves to quantify these effects. 相似文献
128.
Skolotnev S. G. Sanfilippo A. Peyve A. A. Nestola Y. Sokolov S. Yu. Petracchini L. Dobrolybova K. O. Basch V. Pertsev A. N. Ferrando C. Ivanenko A. N. Sani C. Razumovskii A. A. Muccini F. Bich A. S. Palmiotto C. Brusilovsky Y. V. Bonatti E. Sholukhov K. N. Cuffaro M. Veklich I. A. Ligi M. Dobrolybov V. N. 《Doklady Earth Sciences》2021,497(1):191-194
Doklady Earth Sciences - The geological and geophysical data obtained during the 50th cruise of R/V Akademik Nikolaj Strakhov on the Charlie Gibbs megatransform system structure... 相似文献
129.
<正>Global climate change is a common challenge facing mankind, which has evolved from a scientific issue into a global economic and political issue of universal concern to the international community(IPCC, 2007). Global surface temperature was 1.1°C higher in 2011–2020 than that in 1850–1900, and has increased faster since 1970 than in any other 50-year period over at least the last 2000 years(IPCC, 2023). 相似文献
130.
Andrea Dutton Giovanni Scicchitano Carmelo Monaco Jolyon M. Desmarchelier Fabrizio Antonioli Kurt Lambeck Tezer M. Esat L. Keith Fifield Malcolm T. McCulloch Graham Mortimer 《Quaternary Geochronology》2009,4(1):2-10
We have established a plausible rate of uplift near Siracusa in southeastern Sicily (Italy) over the last glacial–interglacial cycle using U-series ages of submerged speleothem calcite and 14C ages of calcite serpulid layers that encrust the speleothems during cave submergence. The precisely determined ages of these sea level benchmarks were compared with expected relative sea level position based on glacio-hydro-isostatic modeling to assess the rate of uplift in this region. When combined with the age of various late Holocene archaeological sites that have been recently described and characterized in terms of their functional position relative to sea level these data collectively define a rate of uplift ≤0.4 mm a?1 along this portion of the Sicilian coastline. These results are consistent with an age assignment of marine isotope stage (MIS) 5.3 or 5.5 for the Akradina terrace, which in turn places temporal constraints on paleoshorelines above and below this level. 相似文献