A possible solar-wind cause of the segmented appearance and of the changes in orientation of the plasma-tail axis of Comet Austin 1982g     

Marco Fulle  Luigi Pansecchi 《Icarus》1984,57(3):410-421

Several directional discontinuities in the plasma tail of Comet Austin 1982g are apparent on photographs obtained by different observers between 1982 Augut 17.84 and August 21.85. Furthermore, anomalous changes in the orientation of the inner tail axis with respect to the projection on the sky of the prolonged radius vector are noticed. An analysis based on the wind-sock theory of plasma comet tail orientations shows that changes in the azimuthal component of the solar-wind velocity would have produced the observed anomalies. No satellite data on interplanetary conditions were available to check the existence of such a solar-wind event. A type II–IV solar radio event observed on August 17.64, followed by a geomagnetic storm in August 20.67, might denote, however, the existence of a solar flare-generated interplanetary disturbance.  相似文献   

The determination of deep temperatures by means of the CO-CO2-H2-H2O geothermometer: an example using fumaroles in the Campi Flegrei,Italy. A comment     

Roberto Cioni  Luigi Marini 《Bulletin of Volcanology》1990,53(1):67-69

Three points raised in the paper by Tedesco and Sabroux (1987) are dealt with. (1) The inconsistency between the water partial pressure calculated by Tedesco and Sabroux (1987) and saturation pressure is due to the improper use of the water-gas-shift reaction as a geothermometer. In fact Tedesco and Sabroux (1987) do not take into account the distribution of gas species between the coexisting vapour and liquid phases. (2) The depth of the “steam reservoir” is evaluated by Tedesco and Sabroux (1987) in too simplistic a way. This matter should be treated with greater care owing to the high social impact of any consideration on the Phlegraean Fields system. (3) The reliability of carbon monoxide determination at the concentration level encountered at Solfatara depends on the collection method rather than on the gas-chromatographic technique.  相似文献   

The Double Solid Reactant Method for modeling the release of trace elements from dissolving solid phases: I. Outline and limitations     

Marina Accornero  Luigi Marini 《Environmental Geology》2008,55(8):1627-1635

A Double Solid Reactant Method was elaborated from a suggestion of Marini (Geological sequestration of carbon dioxide: Thermodynamics, kinetics, and reaction path modeling. Developments in Geochemistry, Elsevier, Amsterdam, 2007) to simulate the release of trace elements during the progressive dissolution of solid phases. The method is based on the definition, for each dissolving solid, of both an entity whose thermodynamic and kinetic properties are known (either a pure mineral or a solid mixture) and a special reactant, that is, a material of known stoichiometry and unknown thermodynamic and kinetic properties. The special reactant is utilised to take into account the concentrations of trace elements in the dissolving solid phase. In this communication, the influence of several trace elements on the ΔG _f ^o, ΔG _r ^o and log K of the minerals considered by Lelli et al. (Environ Geol, 2007) and Accornero and Marini (Geobasi, 2007a; Proceedings of IMWA symposium, Cagliari, 27–31 May 2007b) was evaluated assuming ideal mixing in the solid state. These effects were found to be negligible for albite and the leucite–latitic glass, limited for muscovites and chlorites, and slightly more important for apatites. These influences become progressively higher with increasing concentration of trace elements in these minerals. Based on these deviations in thermodynamic parameters, special reactants should not include oxide components with molar fractions higher than 0.003. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.

Luigi MariniEmail:

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Pressure dependence of structural parameters of paragonite     

Paola Comodi  Pier Francesco Zanazzi 《Physics and Chemistry of Minerals》1997,24(4):274-280

The compressibility and structure of a 2M₁ paragonite with composition [Na_0.88K_0.10Ca_0.01Ba_0.01] [Al_1.97Ti_0.007Fe_0.01Mn_0.002Mg_0.006]Si_3.01Al_0.99O₁₀OH₂ were determined at pressures between 1 bar and 41 kbar, by single crystal X-ray diffraction using a Merrill-Bassett diamond anvil cell. Compressibility turned out to be largely anisotropic, linear compressibility coefficients parallel to the unit cell edges being β_a=3.5(1)·10^?4, β_b=3.6(1)·10^?4, β_c=8.3(3)·10^?4 kbar^?1 (β_a:β_b·β_c=1:1028:2.371). The isothermal bulk modulus, calculated as the reciprocal of the mean compressibility of the cell volume, was 650(20) kbar. The main features of the deformation mechanism resulting from structural refinements at pressures of 0.5, 25.4, 40.5 kbar were: –?variation in sheet thickness, showing that compression of the c parameter was mainly due to the interlayer thickness reduction from 3.07 Å at 0.5 kbar to 2.81 Å at 40.5 kbar; –?the compressibility of octahedra was greater than that of tetrahedra, the dimensional misfit between tetrahedral and octahedral sheets increased with P, so that tetrahedral rotation angel α increased from 15° at 0.5 kbar to 21.6° at 40.5 kbar; –?the basal surface corrugation (Δz) of the tetrahedral layer, due to the different dimensions of M1 and M2 octahedra and to the octahedral distortion, decreased with P (Δz=0.19 and 0.12 Å at 0.5 and 40.5 kbar respectively). Comparison of the new data on paragonite with those of a K-muscovite and a Na-rich muscovite (Comodi and Zanazzi 1995) revealed a clear trend toward decreasing of compressibility when Na substitutes for K atoms in the interlayer sites.  相似文献   

An Investigation of the Eddy-Covariance Flux Imbalance in a Year-Long Large-Eddy Simulation of the Weather at Cabauw   总被引：1，自引：0，他引：1  

Jerôme Schalkwijk  Harm J. J. Jonker  A. Pier Siebesma 《Boundary-Layer Meteorology》2016,160(1):17-39

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FAOSTAT estimates of greenhouse gas emissions from biomass and peat fires     

Simone Rossi  Francesco N. Tubiello  Paolo Prosperi  Mirella Salvatore  Heather Jacobs  Riccardo Biancalani  Joanna I. House  Luigi Boschetti 《Climatic change》2016,135(3-4):699-711

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Erratum to: FAOSTAT estimates of greenhouse gas emissions from biomass and peat fires     

Simone Rossi  Francesco N. Tubiello  Paolo Prosperi  Mirella Salvatore  Heather Jacobs  Riccardo Biancalani  Joanna I. House  Luigi Boschetti 《Climatic change》2016,135(3-4):713-713

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The resolution sensitivity of the South Asian monsoon and Indo-Pacific in a global 0.35° AGCM     

Stephanie J. Johnson  Richard C. Levine  Andrew G. Turner  Gill M. Martin  Steven J. Woolnough  Reinhard Schiemann  Matthew S. Mizielinski  Malcolm J. Roberts  Pier Luigi Vidale  Marie-Estelle Demory  Jane Strachan 《Climate Dynamics》2016,46(3-4):807-831

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Projected changes in medicanes in the HadGEM3 N512 high-resolution global climate model     

M. Tous  G. Zappa  R. Romero  L. Shaffrey  P. L. Vidale 《Climate Dynamics》2016,47(5-6):1913-1924

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Elasticità e plasticità nella contrazione di volume di un solido isotropo sottoposto a pressione idrostatica     

Prof. Luigi Castoldi 《Pure and Applied Geophysics》1953,25(1):6-12

Riassunto Si prospetta una teoria della comprimibilità di un solido isotropo soggetto a pressione idrostatica, implicante il comportamento plastico ad elevate pressioni. Si ottiene in tal modo un accordo coi risultati sperimentali sensibilmente superiore a quello fin qui conseguito ritenendo il fenomeno di natura puramente elastica ed applicado ad esso la cosìddetta «approssimazione del second'ordine».

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Summary A theory of the comprimibility for isotropic solids, whith regard to their plastic properties, is proposed. Check whith experimental data furnishes more satisfactory results than current theory of second approximation.

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