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1.
Quantum theory in Robertson – Walker spacetime suggests the existence of a minimal energy ε of the order of 10−45 erg. Reasonable forms for ε give the expansion factor R=R(t)(t= the cosmic time) with no need of gravitational field equations.Einstein's theory should be modified in gravitational fields of strength less than ε c/ħ ∼ 10−8 cm/s2 where c is the speed of light and ħ is the reduced Planck constant. The cosmological term λ is expected to decrease as the universe expands.In the Appendix, ε is derived from a big bang – big crunch Newtonian cosmology.  相似文献   
2.
The inception and growth of the active Carpino-Le Piane Basin Fault System (CLPBFS; central-southern Apennines, Italy) was analysed with respect to the neighbouring Isernia and Surrounding (ISFS) and Boiano Basin (BBFS) extensional Fault Systems. 39Ar–40Ar dating showed that the BBFS was already active 649 ± 21 ka bp and that the ISFS was active at least 476 ±10 ka bp , whereas the activity of the CLPBFS started certainly later than 253 ± 22 ka bp , and very probably as recently as <28 ka bp . These ages, combined with structural data (geometry and kinematics of the fault systems), indicate that the inception and development of the CLPBFS could be strictly related to the stress changes caused by earthquakes occurring on the BBFS.  相似文献   
3.
The possibility that the gravitational coupling constantG is an increasing function of the cosmic timet is discussed.In Section 1 the Maximal Power Hypothesis (MPH) stating that no power in Nature can exceed the upper boundc 5/G (Gunn's luminosity) is advocated.In Sections 2, 3, and 4 the MPH is employed on the cosmological scale to support the idea of an increasingG. In Section 2 the increasingG is obtained by two assumptions - the MPH and the energy conservation law - and by nothing else.In Section 3 the increasingG follows naturally from the MPH in the Einstein-Cartan theory of gravity. The arguments proposed in Sections 2 and 3 lead todG(t)/dt > 0 but cannot specify the form ofG(t). In Section 4 the MPH is applied to the energy of the vacuum and leads to a relation betweenG and the cosmological term,G S 3, valid in a matter-dominated universe (S =S(t) is the expansion factor). This relation plus the time-dependence law (suggested by many authors) t 2 = constant, plustH > 2/3 (suggested by observations on the age of globular clusters;H is the Hubble parameter) implies an increasingG. One finds also GU, whereU is the mass density of the universe, in agreement with other studies.  相似文献   
4.
Governmental authorities are forced by law to make decisions within the framework of European, national and regional directives in the fields of spatial planning, groundwater and environmental protection. These tasks can be supported by a decision-support system, which integrates data from various sources and helps to make decision processes more effective and transparent. Basic work for such a decision support system has been done in a transnational and interdisciplinary project (Interreg II C: KATER), including metadata definition, metadata system, cartographic tools and GIS tools. The direct integration of these tools and information in the decision process will be implemented in the next few years (project KATER II).  相似文献   
5.
A multi‐method approach (palaeothermal and thermochronological analyses; thermal modelling) is applied to reconstruct the exhumation history of the Altotiberina Fault (ATF), a representative example of crustal‐scale active low‐angle normal faulting in the Northern Apennines (Italy). Thermal maturity and thermochronological data yield similar burial histories but different exhumation patterns for the sedimentary successions in the hangingwall and the footwall of the ATF. Since 3.8 Ma, the ATF footwall has exhumed at rates of 0.90 mm a?1. Exhumation led to bending and deactivation of the ATF uppermost portion as a result of tectonic unloading and isostatic adjustment, followed by migration of extension and the development of a set of domino‐like, east‐dipping normal faults, rooting on the buried portion of the ATF. ATF activity and isostatic rebound exhumed Triassic rock units from depths of about 4 km. We suggest that isostatic instability is accommodated at shallow crustal levels, in a similar way to what is observed on larger structures at mid‐low crustal levels.  相似文献   
6.
A pollen record from a sediment core drilled underneath the Acheulian site of Fontana Ranuccio provides new data on the vegetation characters in central Italy during the late Early Pleistocene, in a forest phase possibly corresponding to a substage of Marine Isotope Stage 21. A number of tree taxa nowadays extinct in Europe (Cathaya, Tsuga, Taxodium type, Carya and Pterocarya) are present at Fontana Ranuccio in a temperate phase characterised by dense forest conditions, dominated by Alnus and Pterocarya. The comparison of the Fontana Ranuccio record with other dated sites distributed along the Italian peninsula indicates that the floristic and vegetational characters of the Mid Pleistocene revolution present a rather distinct succession of biostratigraphic events. Compared to other Early Pleistocene pollen records from southern Europe, the Italian Peninsula shows greater floristic similarities with the Eastern Mediterranean regions than with the Iberian Peninsula. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   
7.
An extensive dataset of vitrinite reflectance, FTIR parameters on organic matter, illite content in mixed layers illite‐smectite, apatite fission tracks and U‐Th/He dating has been used to reconstruct the stepwise propagation of the Eastern Sicily fold‐and‐thrust belt during Late Palaeogene and Neogene times. The results indicate that the fold‐and‐thrust belt is divisible into two levels of thermal maturity. These levels consist of a less evolved level of thermal maturity that records limited sedimentary burial and minor heating, and a more evolved level of thermal maturity that indicates tectonic burial and exhumation at different times. Deformation and exhumation of shallowly buried units are linked to wedge forward propagation by low‐angle thrusts, whereas the evolution of deeply buried units is associated with tectonic imbrications by duplex formation and steep thrusts. The two tectonic styles alternate during evolution of the fold‐and‐thrust belt under low erosion rates.  相似文献   
8.
The planetary boundary-layer (PBL) parameterization is a key issue for the definition of initial wind flow fields in diagnostic models. However, PBL theories usually treat separately stable, neutral, and convective stability conditions, so that their implementation in diagnostic wind models is not straightforward. In the present paper, an attempt is made to adopt a comprehensive PBL parameterisation, covering stable/neutral and unstable atmospheric conditions, which appears suitable to diagnostic models. This parameterisation is implemented into our diagnostic mass-consistent code. A validation of the consistency between the implemented PBL parameterisations has been checked through an analysis of the sensitivity of the vertical wind profiles to atmospheric stability.  相似文献   
9.
Concentrations of chlorinated hydrocarbons (DDT and metabolites, PCBs, aldrin, dieldrin, HCB and BHCs) have been determined in the tissues of five species of marine animals sampled in selected areas of the central Mediterranean.  相似文献   
10.
The levels of PCBs, DDT and BHC residues have been determined in thalli of 12 species of marine algae harvested along the east coast of Sicily. The results are discussed in comparison with those obtained earlier with animal species sampled in the same area.  相似文献   
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