Phase relations and formation of sodium-rich majoritic garnet in the system Mg3Al2Si3O12–Na2MgSi5O12 at 7.0 and 8.5 GPa     

A. V. Bobrov  Yu. A. Litvin  L. Bindi  A. M. Dymshits 《Contributions to Mineralogy and Petrology》2008,156(2):243-257

The pseudo-binary system Mg₃Al₂Si₃O₁₂–Na₂MgSi₅O₁₂ modelling the sodium-bearing garnet solid solutions has been studied at 7 and 8.5 GPa and 1,500–1,950°C. The Na-bearing garnet is a liquidus phase of the system up to 60 mol% Na₂MgSi₅O₁₂ (NaGrt). At higher content of NaGrt in the system, enstatite (up to ∼80 mol%) and then coesite are observed as liquidus phases. Our experiments provided evidence for a stable sodium incorporation in garnet (0.3–0.6 wt% Na₂O) and its control by temperature and pressure. The highest sodium contents were obtained in experiments at P = 8.5 GPa. Near the liquidus (T = 1,840°C), the equilibrium concentration of Na₂O in garnet is 0.7–0.8 wt% (∼6 mol% Na₂MgSi₅O₁₂). With the temperature decrease, Na concentration in Grt increases, and the maximal Na₂MgSi₅O₁₂ content of ∼12 mol% (1.52 wt% Na₂O) is gained at the solidus of the system (T = 1,760°С). The data obtained show that most of natural diamonds, with inclusions of Na-bearing garnets usually containing <0.4 wt% Na₂O, could be formed from sodium-rich melts at pressures lower than 7 GPa. Majoritic garnets with higher sodium concentrations (>1 wt% Na₂O) may crystallize at a pressure range of 7.0–8.5 GPa. However the upper pressure limit for the formation of naturally occurring Na-bearing garnets is restricted by the eclogite/garnetite bulk composition.  相似文献   

Reuse of residual sludge from stone processing: differences and similarities between sludge coming from carbonate and silicate stones—Italian experiences     

N. Careddu  G. A. Dino 《Environmental Earth Sciences》2016,75(14):1075

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Chaos in N-body systems     

Dino Boccaletti  giuseppe Pucacco   《Planetary and Space Science》1998,46(11-12)

Here is a selection of applications of what is now called theory of dynamical systems in galactic dynamics and N-body systems. The study of chaotic motions in potentials used as a model for elliptical galaxies is a first example of these applications. The interest in this problem stems from the fact that there are now many theoretical and observational evidences that the overall potentials of galaxies are indeed non-integrable. There are classes of objects, for example small and intermediate luminosity elliptical galaxies, for which the presence of the famous third integral is not necessary or others in which we observe peculiarities in their photometry or kinematics. We address here some of these issues and their implications in modifying our current understanding of the structure and evolution of galaxies.More in general, there is the natural question of how the systems we see have settled to their present status and what would happen if some external cause perturbs it. This issue is related to the question of the stochasticity involved in the general N-body dynamics, especially when N is very large. An N-body dynamical system is definitely chaotic, as shown by several numerical investigations, at least for N not very large. However, this statement must be reconciled with the picture of non-collisional equilibrium of big systems. The second part of this review presents a survey of numerical experiments and an interpretation of the results obtained using standard chaoticity indicators.  相似文献   

Erratum to: Pan-European ground-motion prediction equations for the average horizontal component of PGA,PGV, and 5 %-damped PSA at spectral periods up to 3.0 s using the RESORCE dataset   总被引：2，自引：2，他引：0  

D. Bindi  M. Massa  L. Luzi  G. Ameri  F. Pacor  R. Puglia  P. Augliera 《Bulletin of Earthquake Engineering》2014,12(1):431-448

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Combining Seismic Noise Techniques for Landslide Characterization     

Marco Pilz  Stefano Parolai  Dino Bindi  Annamaria Saponaro  Ulan Abdybachaev 《Pure and Applied Geophysics》2014,171(8):1729-1745

A strong topographic relief and the presence of weakly consolidated sediments create favorable conditions for the development of landslides around the eastern rim of the Fergana Basin (Central Asia). In summer 2012, a field experiment employing small aperture seismic arrays was carried out on an unstable slope, using ambient vibration recordings. The aim of the study was to constrain the seismic response of a potential future landslide and to map lateral and vertical changes in the shear-wave velocity of the surficial soil layers. Strong variations of horizontal-to-vertical spectral ratios in terms of amplitude and directionality indicated clear differences in local site effects, probably reflecting the stability of different sections of the slope. Results further showed resonant frequencies of both the entire unstable block, as well as for smaller, individual parts. The use of an ad hoc, passive seismic tomography approach based on noise correlograms allowed for the mapping of the shear-wave velocities of the sliding material, even in cases of significant topography relief. Based on the recording of seismic noise only, we clearly identified a low-velocity body of weakly consolidated claystone and limestone material, which can be interpreted as the landslide body, with laterally varying thickness.  相似文献   

Partially non-ergodic region specific GMPE for Europe and Middle-East   总被引：2，自引：2，他引：0  

Sreeram Reddy Kotha  Dino Bindi  Fabrice Cotton 《Bulletin of Earthquake Engineering》2016,14(4):1245-1263

The ergodic assumption considers the time sampling of ground shaking generated in a given region by successive earthquakes as equivalent to a spatial sampling of observed ground motion across different regions. In such cases the estimated aleatory variability in source, propagation, and site seismic processes in ground motion prediction equations (GMPEs) is usually larger than with a non-ergodic approach. With the recently published datasets such as RESORCE for Europe and Middle-East regions, and exploiting algorithms like the non-linear mixed effects regression it became possible to introduce statistically well-constrained regional adjustments to a GMPE, thus ‘partially’ mitigating the impact of the assumption on regional ergodicity. In this study, we quantify the regional differences in the apparent attenuation of high frequency ground motion with distance and in linear site amplification with V_s30, between Italy, Turkey, and rest of the Europe-Middle-East region. With respect to a GMPE without regional adjustments, we obtain up to 10 % reduction in the aleatory variability σ, primarily contributed by a 20 % reduction in the between-station variability. The reduced aleatory variability is translated into an epistemic uncertainty, i.e. a standard error on the regional adjustments which can be accounted for in the hazard assessment through logic-tree branches properly weighted. Furthermore, the between-event variability is reduced by up to 30 % by disregarding in regression the events with empirically estimated moment magnitude. Therefore, we conclude that a further refinement of the aleatory variability could be achieved by choosing a combination of proxies for the site response, and through the homogenization of the magnitude scales across regions.  相似文献   

Climatic changes and associated impacts in the Mediterranean resulting from a 2 °C global warming   总被引：1，自引：0，他引：1  

C. Giannakopoulos  P. Le Sager  M. Bindi  M. Moriondo  E. Kostopoulou  C.M. Goodess 《Global and Planetary Change》2009,68(3):209-224

Climatic changes over the Mediterranean basin in 2031–2060, when a 2 °C global warming is most likely to occur, are investigated with the HadCM3 global circulation model and their impacts on human activities and natural ecosystem are assessed. Precipitation and surface temperature changes are examined through mean and extreme values analysis, under the A2 and B2 emission scenarios. Confidence in results is obtained via bootstrapping. Over the land areas, the warming is larger than the global average. The rate of warming is found to be around 2 °C in spring and winter, while it reaches 4 °C in summer. An additional month of summer days is expected, along with 2–4 weeks of tropical nights. Increase in heatwave days and decrease in frost nights are expected to be a month inland. In the northern part of the basin the widespread drop in summer rainfall is partially compensated by a winter precipitation increase. One to 3 weeks of additional dry days lead to a dry season lengthened by a week and shifted toward spring in the south of France and inland Algeria, and autumn elsewhere. In central Mediterranean droughts are extended by a month, starting a week earlier and ending 3 weeks later. The impacts of these climatic changes on human activities such as agriculture, energy, tourism and natural ecosystems (forest fires) are also assessed. Regarding agriculture, crops whose growing cycle occurs mostly in autumn and winter show no changes or even an increase in yield. In contrast, summer crops show a remarkable decrease of yield. This different pattern is attributed to a lengthier drought period during summer and to an increased rainfall in winter and autumn. Regarding forest fire risk, an additional month of risk is expected over a great part of the basin. Energy demand levels are expected to fall significantly during a warmer winter period inland, whereas they seem to substantially increase nearly everywhere during summer. Extremely high summer temperatures in the Mediterranean, coupled with improved climate conditions in northern Europe, may lead to a gradual decrease in summer tourism in the Mediterranean, but an increase in spring and autumn.  相似文献   

“Galileo Galilei” (GG) a small satellite to test the equivalence principle of Galileo, Newton and Einstein     

Anna M. Nobili  Gian Luca Comandi  Suresh Doravari  Donato Bramanti  Rajeev Kumar  Francesco Maccarrone  Erseo Polacco  Slava G. Turyshev  Michael Shao  John Lipa  Hansjoerg Dittus  Claus Laemmerzhal  Achim Peters  Jurgen Mueller  C. S. Unnikrishnan  Ian W. Roxburgh  Alain Brillet  Christian Marchal  Jun Luo  Jozef van der Ha  Vadim Milyukov  Valerio Iafolla  David Lucchesi  Paolo Tortora  Paolo De Bernardis  Federico Palmonari  Sergio Focardi  Dino Zanello  Salvatore Monaco  Giovanni Mengali  Luciano Anselmo  Lorenzo Iorio  Zoran Knezevic 《Experimental Astronomy》2009,23(2):689-710

“Galileo Galilei” (GG) is a small satellite designed to fly in low Earth orbit with the goal of testing the Equivalence Principle—which is at the basis of the General Theory of Relativity—to 1 part in 10¹⁷. If successful, it would improve current laboratory results by 4 orders of magnitude. A confirmation would strongly constrain theories; proof of violation is believed to lead to a scientific revolution. The experiment design allows it to be carried out at ambient temperature inside a small 1-axis stabilized satellite (250 kg total mass). GG is under investigation at Phase A-2 level by ASI (Agenzia Spaziale Italiana) at Thales Alenia Space in Torino, while a laboratory prototype (known as GGG) is operational at INFN laboratories in Pisa, supported by INFN (Istituto Nazionale di fisica Nucleare) and ASI. A final study report will be published in 2009.  相似文献   

Projected shifts of wine regions in response to climate change   总被引：1，自引：1，他引：0  

M. Moriondo  G. V. Jones  B. Bois  C. Dibari  R. Ferrise  G. Trombi  M. Bindi 《Climatic change》2013,119(3-4):825-839

This research simulates the impact of climate change on the distribution of the most important European wine regions using a comprehensive suite of spatially informative layers, including bioclimatic indices and water deficit, as predictor variables. More specifically, a machine learning approach (Random Forest, RF) was first calibrated for the present period and applied to future climate conditions as simulated by HadCM3 General Circulation Model (GCM) to predict the possible spatial expansion and/or shift in potential grapevine cultivated area in 2020 and 2050 under A2 and B2 SRES scenarios. Projected changes in climate depicted by the GCM and SRES scenarios results in a progressive warming in all bioclimatic indices as well as increasing water deficit over the European domain, altering the climatic profile of each of the grapevine cultivated areas. The two main responses to these warmer and drier conditions are 1) progressive shifts of existing grapevine cultivated area to the north–northwest of their original ranges, and 2) expansion or contraction of the wine regions due to changes in within region suitability for grapevine cultivation. Wine regions with climatic conditions from the Mediterranean basin today (e.g., the Languedoc, Provence, Côtes Rhône Méridionales, etc.) were shown to potentially shift the most over time. Overall the results show the potential for a dramatic change in the landscape for winegrape production in Europe due to changes in climate.  相似文献   

Attenuation,source parameters and site effects in the Irpinia–Basilicata region (southern Apennines,Italy)     

Luciana Cantore  Adrien Oth  Stefano Parolai  Dino Bindi 《Journal of Seismology》2011,15(2):375-389

We derive S-wave attenuation characteristics, earthquake source parameters and site amplification functions at seismic stations used for earthquake early warning in the Irpinia–Basilicata region, using non-parametric spectral inversion of seismograms from 49 local events with M _L = 1.5–3.1. We obtain relatively low Q values (Q ₀ = 28 at a frequency of 1 Hz) in conjunction with a strong frequency-dependence (close to linear). The source spectra can be satisfactorily modeled using the omega-square model, with stress drops ranging between 0.01–2 MPa, and in the narrow magnitude range available for analysis, the source spectra seem to scale self-similarly. The local magnitude M _L shows a linear correlation with moment magnitude M _W, however with a systematic underestimation by about 0.5-magnitude units. The results obtained in this work provide important insights into the ground-motion characteristics that are required for appropriate seismic hazard assessment and are of practical relevance for a suite of applications, such as the calibration of ground-motion prediction equations or the correction for site amplification in earthquake early warning and rapid calculation of shake-maps for seismic emergency management.  相似文献