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Armenise I.,CNR Institute of Inorganic Methodologies and Plasmas | Kustova E.V.,Saint Petersburg State University
Chemical Physics | Year: 2014

In the present paper, state-to-state model of vibrational-chemical kinetic and transport processes is applied to study heat and mass transfer in non-equilibrium flows of CO2 and air mixtures under atmospheric entry conditions. Different contributions to the heat flux typical for the state-to-state approach are considered: fluxes due to heat conduction, mass diffusion, thermal diffusion, and diffusion of vibrational energy. For several test cases, vibrational distributions, chemical composition, temperature profiles as well as the transport coefficients and heat flux are calculated along the stagnation line. Various models for diffusion velocities are considered. For a non-catalytic surface, the role of thermal diffusion process is found to be important in some test cases. Prandtl and Schmidt numbers are calculated along the stagnation line, and it is shown that they are essentially non-constant. The influence of Prandtl and Schmidt numbers on the diffusion velocities and heat flux is evaluated. © 2013 Elsevier B.V. All rights reserved. Source


Senesi G.S.,CNR Institute of Inorganic Methodologies and Plasmas
Earth-Science Reviews | Year: 2014

Thanks to its unique, unprecedented and very appealing analytical capabilities and performances, the Laser-Induced Breakdown Spectroscopy (LIBS) technique has expanded rapidly in the last two decades in several fields of academic and applicative research, including the study of geomaterials. This review mainly consists of two parts, the first one provides a general and brief summary and discussion of the basic theory and principles of LIBS, the experimental set-up of conventional laboratory bench-top and portable, remote and stand-off configurations, the main methodologies of qualitative and quantitative LIBS analysis with the support of chemometric approaches, and the advantages and disadvantages of the technique. The second part aims to provide a comprehensive, detailed and adjourned at-my-best overview of the huge work done on LIBS applications to the study of geomaterials with focus on minerals and rocks. In particular, results obtained on element detection and quantification, identification, discrimination, classification, provenance, weathering and alteration of minerals, igneous, sedimentary and metamorphic rocks, gemstones, mine ores, archeological artifacts and speleothems, are reviewed and briefly discussed. The enormous efforts and remarkable progresses made in the last decade by several research groups on the potential and viable use of LIBS on robotic vehicles for studying meteorites and planetary analogue terrestrial rocks in simulated planetary conditions, have also been reviewed. © 2014 Elsevier B.V.. Source


Iorio L.,CNR Institute of Inorganic Methodologies and Plasmas
International Journal of Modern Physics D | Year: 2015

Mindful of the anomalous perihelion precession of Mercury discovered by Le Verrier in the second half of the nineteenth century and its successful explanation by Einstein with his General Theory of Relativity in the early years of the twentieth century, discrepancies among observed effects in our Solar system and their theoretical predictions on the basis of the currently accepted laws of gravitation applied to known matter-energy distributions have the potential of paving the way for remarkable advances in fundamental physics. This is particularly important now more than ever, given that most of the universe seems to be made of unknown substances dubbed Dark Matter and Dark Energy. Should this not be directly the case, Solar system's anomalies could anyhow lead to advancements in either cumulative science, as shown to us by the discovery of Neptune in the first half of the nineteenth century, and technology itself. Moreover, investigations in one of such directions can serendipitously enrich the other one as well. The current status of some alleged gravitational anomalies in the Solar system is critically reviewed. They are: (a) Possible anomalous advances of planetary perihelia. (b) Unexplained orbital residuals of a recently discovered moon of Uranus (Mab). (c) The lingering unexplained secular increase of the eccentricity of the orbit of the Moon. (d) The so-called Faint Young Sun Paradox. (e) The secular decrease of the mass parameter of the Sun. (f) The Flyby Anomaly. (g) The Pioneer Anomaly. (h) The anomalous secular increase of the astronomical unit. © 2015 World Scientific Publishing Company. Source


Iorio L.,CNR Institute of Inorganic Methodologies and Plasmas
International Journal of Modern Physics D | Year: 2015

The orbital dynamics of a test particle moving in the nonspherically symmetric field of a rotating oblate primary is impacted also by certain indirect, mixed effects arising from the interplay of the different Newtonian and post-Newtonian accelerations which induce known direct perturbations. We systematically calculate the indirect gravitoelectromagnetic shifts per orbit of the Keplerian orbital elements of the test particle arising from the crossing among the first even zonal harmonic J2 of the central body and the post-Newtonian static and stationary components of its gravitational field. We also work out the Newtonian shifts per orbit of order J22, and the direct post-Newtonian gravitoelectric effects of order J2c-2 arising from the equations of motion. In the case of both the indirect and direct gravitoelectric J2c-2 shifts, our calculation holds for an arbitrary orientation of the symmetry axis of the central body. We yield numerical estimates of their relative magnitudes for systems ranging from Earth's artificial satellites to stars orbiting supermassive black holes. As far as their measurability is concerned, highly elliptical orbital configuration are desirable. © 2015 World Scientific Publishing Company. Source


Taccogna F.,CNR Institute of Inorganic Methodologies and Plasmas
European Physical Journal D | Year: 2014

The collisionless plasma sheath represents an important example of Vlasov theory application. In this study, Particle-in-Cell/Monte Carlo Collision methodology has been used to study different examples of plasma sheaths under strong negative charge emission from surface. Secondary electrons emitted by primary electrons (acceleration region of Hall-effect discharge) and by photons (dusty plasma) are responsible for a complete inverse sheath: the potential monotonically increases toward a positively charged wall that is shielded by a single layer of negative charge. No ion-accelerating presheath exists in the bulk plasma region and the ion flux at the wall is zero. In the case of production of hydrogen negative ions by neutral conversion on the plasma grid in the extraction region of a negative ion source, a space-charge-limited regime occurs with the formation of a non-monotonic double layer in front of the grid. © 2014 EDP Sciences, SIF, Springer-Verlag Berlin Heidelberg. Source

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