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On a unique behavior of freshwater bacteria 总被引:1,自引:1,他引:0
Salvatore BELLINI 《中国海洋湖沼学报》2009,27(1):3-5
Magnetic sensitivity has been found in bacteria from freshwater sites around Pavia, Italy. 相似文献
84.
Fausto Grassa Giorgio Capasso Rocco Favara Salvatore Inguaggiato 《Pure and Applied Geophysics》2006,163(4):781-807
Hydrochemical (major and some minor constituents), stable isotope ( and , δ13CTDIC total dissolved inorganic carbon) and dissolved gas composition have been determined on 33 thermal discharges located throughout
Sicily (Italy) and its adjacent islands. On the basis of major ion contents, four main water types have been distinguished:
(1) a Na-Cl type; (2) a Ca-Mg > Na-SO4-Cl type; (3) a Ca-Mg-HCO3 type and (4) a Na-HCO3 type water. Most waters are meteoric in origin or resulting from mixing between meteoric water and heavy-isotope end members.
In some samples, δ18O values reflect the effects of equilibrium processes between thermal waters and rocks (positive 18O-shift) or thermal waters and CO2 (negative 18O-shift). Dissolved gas composition indicates the occurrence of gas/water interaction processes in thermal aquifers. N2/O2 ratios higher than air-saturated water (ASW), suggest the presence of geochemical processes responsible for dissolved oxygen
consumption. High CO2 contents (more than 3000 cc/litre STP) dissolved in the thermal waters indicate the presence of an external source of carbon
dioxide-rich gas. TDIC content and δ13CTDIC show very large ranges from 4.6 to 145.3 mmol/Kg and from –10.0‰ and 2.8‰, respectively. Calculated values indicate the significant
contribution from a deep source of carbon dioxide inorganic in origin. Interaction with Mediterranean magmatic CO2 characterized by heavier carbon isotope ratios ( value from -3 to 0‰ vs V-PDB (CAPASSO et al., 1997, GIAMMANCO et al., 1998; INGUAGGIATO et al., 2000) with respect to MORB value and/or input of CO2-derived from thermal decomposition of marine carbonates have been inferred. 相似文献
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Salvatore Capozziello Mauro Francaviglia Andrey N. Makarenko 《Astrophysics and Space Science》2014,349(1):603-609
We study cosmological models derived from higher-order Gauss-Bonnet gravity F(R,G) by using the Lagrange multiplier approach without assuming the presence of additional fields with the exception of standard perfect fluid matter. The presence of Lagrange multipliers reduces the number of allowed solutions. We need to introduce compatibility conditions of the FRW equations, which impose strict restrictions on the metric or require the introduction of additional exotic matter. Several classes of F(R,G) models are generated and discussed. 相似文献
88.
Relative motion improvements have traditionally focused on inserting additional force models into existing formulations to achieve greater fidelity, or complex expansions to admit eccentric orbits for propagation. A simpler approach may be numerically integrating the two satellite positions and then converting to a modified equidistant cylindrical frame for comparison in a Hill’s-like frame. Recent works have introduced some approaches for this transformation within the Hill’s construct, and examined the accuracy of the transformation. Still others have introduced transformations as they apply to covariance operations. Each of these has some orbital or force model limitations and defines an approximate circular reference dimension. We develop a precise transformation between the Cartesian and curvilinear frame along the actual satellite orbit and test the results for various orbital classes. The transformation has wide applicability. 相似文献
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Francesco?PerriEmail author Salvatore?Critelli Giovanni?Mongelli Robert?L.?Cullers 《International Journal of Earth Sciences》2011,100(7):1569-1587
The continental redbeds from the Internal Domains of the central-western Mediterranean Chains have an important role in the
palaeogeographic and palaeotectonic reconstructions of the Alpine circum-Mediterranean orogen evolution since these redbeds
mark the Triassic-Jurassic rift-valley stage of Tethyan rifting. The composition and the sedimentary evolution of the Middle
Triassic to Lowermost Jurassic continental redbeds of the San Marco d’Alunzio Unit (Peloritani Mountains, Southern Italy),
based on mineralogical and chemical analyses, suggests that the studied mudrock sediments share common features with continental
redbeds that constitute the Internal Domains of the Alpine Mediterranean Chains. Phyllosilicates are the main components in
the mudrocks. The 10 Å-minerals (illite and micas), the I–S mixed layers, and kaolinite are the most abundant phyllosilicates.
The amount of illitic layers in I–S mixed layers coupled with the illite crystallinity values (IC) are typical of high degree
of diagenesis, corresponding to a lithostatic/tectonic loading of about 4–5 km. The mineralogical assemblage coupled with
the A-CN-K plot suggest post-depositional K-enrichments. Palaeoweathering proxies (PIA and CIW) record intense weathering
at the source area. Further, the studied sediments are affected by reworking and recycling processes and, as consequence,
it is likely these proxies monitor cumulative effect of weathering. The climate in the early Jurassic favoured recycling and
weathering occurred under hot, episodically humid climate with a prolonged dry season. The source-area is the low-grade Paleozoic
metasedimentary basement. Mafic supply is minor but not negligible as suggested by provenance proxies. 相似文献