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Experimental data on the viscosity and self-diffusion coefficient of two metallic compounds in their fluid phases, i.e. potassium and thallium, are modeled using the translational elastic mode theory which has been successfully applied to the case of water. It is shown that this theory allows the experimental data to be accounted for in accordance with their uncertainties and, above all, it allows the different variations observed between the different authors to be explained. Particularly in the case of thallium, this theory makes it possible to represent viscosity data with much better precision than the so-called reference equation of state. The dilute-gas limit laws connecting various parameters of the theory obtained in the case of water are confirmed here and thus give them a universal character. The elastic mode theory is accompanied by the development of new equations of state, mainly to describe properties along the saturated vapor pressure curve, which greatly extend the temperature range of application of these equations compared to those found in the literature. The whole analysis thus makes it possible to propose precise values of various thermodynamic parameters at the melting and boiling temperature corresponding to atmospheric pressure., Comment: 47 pages, 38 figures, 8 tables. A link in the references will redirect you to the Mathematica computation program download page Accepted for publication in Phys. Fluids

A microscopic model able to describe simultaneously the dynamic viscosity and the self-diffusion coefficient of fluids is presented. This model is shown to emerge from the introduction of fractional calculus in a usual model of condensed matter physics based on an elastic energy functional. The main feature of the model is that all measurable quantities are predicted to depend in a non-trivial way on external parameters (e.g. the experimental set-up geometry, in particular the sample size). On the basis of an unprecedented comparative analysis of a collection of published experimental data, the modeling is applied to the case of water in all its fluid phases, in particular in the supercooled phase. It is shown that the discrepancies in the literature data are only apparent and can be quantitavely explained by the different experimental configurations. This approach makes it possible to reproduce the water viscosity with a better accuracy than the 2008 IAPWS formulation and also with a more physically satisfying modeling of the isochors. Moreover, it also allows the modeling within experimental accuracy of the translational self-diffusion data available in the literature in all water fluid phases. Finally, the formalism of the model makes it possible to understand the anomalies observed on the dynamic viscosity and self-diffusion coefficient and their possible links., Comment: 158 pages, 131 figures and 5 Appendices. A link in the references will redirect you to the program download page for Mathematica or Kaleidagraph

We report data of the O2- ion mobility in neon gas over broad density and temperature ranges along with its theoretical description in terms of the thermodynamic, free volume model that has successfully been adopted for the interpretation of electron and ion mobility in superfluid and normal helium. The free volume model, which is aimed at computing the free volume accessible for the ion motion, along with the Millikan- Cunningham slip factor correction, is able to describe the ion mobility in the crossover region connecting the dilute gas regime described by the classical Kinetic Theory to the high density region ruled by the laws of hydrodynamic transport.

We report new measurements of the mobility \(\mu\) of O$_{2}^{-}$ ions in supercritical neon in the range $45\,\mathrm{K}\le T\le 334\,\mathrm{K}$ for number density $N\ge 0.5\,$nm$^{-3}.$ We rationalize the experimental data of all isotherms with the Stokes-Cunningham formula by computing the ion hydrodynamic radius as a function of \(T \) and \(N\) with the thermodynamic free volume model developed for the ion mobility in superfluid He. The model parameters are determined by re-analyzing published data for $T=45\,$K for \(N\) up to $N\approx 1.65N_{c} $ ($N_{c}\approx 14.4\,$nm$^{-3}$ is the critical number density), which roughly span four orders of magnitude of the Knudsen number $(0.1\le \mathrm{K}_{n}\le 1000)$, covering the transition from the kinetic- to the hydrodynamic transport regime. These parameters provide an excellent description of the dependence of \(\mu\) on \(N\) for all higher isotherms and yield a strict test of the model validity, thereby bridging the gap between the kinetic- and the hydrodynamic transport regimes., Comment: submitted to Plasma Sources Science and Technology

New Molecular Dynamics simulations have been carried out in order to get an insight on the physical mechanisms that determine the drift mobility of negative Oxygen ions in very dense Neon gas in the supercritical phase close to the critical point. Two ion-neutral interaction potentials have been used that differ by their repulsive part. We have observed that the potential with a harder repulsive part gives much better agreement with the experimental data. The differences with the softer repulsive potential previously used are discussed. We propose that the behavior of the ion mobility as a function of the gas density is related to the number of neutral atoms loosely bound in the first solvation shell around the ion., Comment: submitted to IEEE-TDEI, 6 pages, 9 figures

We report here the results of Molecular Dynamics simulations of the drift mobility of negative oxygen ions in very dense neon gas in the supercritical phase. The simulations relatively well reproduce the trend of the experimental data. The rationalization of the mobility behavior as a function of the gas density is given in terms of the number of atoms correlated in the first solvation shell around the ion., Comment: submitted for ICDL 2017 Conference

A new equation of state for argon has been developed in view to extend the range of validity of the equation of state previously proposed by Tegeler et al. (Ref. 4) and to obtain a better physical description of the experimental thermodynamic data for the whole fluid region (single-phase, metastable and saturation states). As proposed by Tegeler et al., this equation is also based on a functional form of the residual part of the reduced Helmholtz free energy. However in this work, the fundamental equation for the Helmholtz free energy has been derived from the measured quantities CV(rho,T) and P(rho,T). The empirical description of the isochoric heat capacity CV(rho,T) is based on an original empirical description containing explicitly the metastable states. The thermodynamic properties (internal energy, entropy, free energy) are then obtained by combining integration of CV(rho,T). The arbitrary functions introduced by the integration process have been deduced from a comparison between calculated and experimental pressure P(rho,T) data. The new formulation is valid for the whole fluid region from the melting line to 2300 K and for pressures up to 50 GPa. It also predicts existence of a maximum of the isochoric heat capacity CV along isochors as experimentally observed in several other fluids. For many applications, an approximate form of the equation of state for the liquid phase may be sufficient. A Tait-Tammann equation is therefore proposed between the triple point temperature and 148 K., Comment: 93 pages, 53 figures, 12 tables, 3 appendix

Compositions of glasses in the Apollo 14 soil correspond to four types of Fra Mauro basalts, to mare basalts and soils, and, in minor amounts, to gabbroic anorthosite and potash granite. The Fra Mauro basalts can be related by simple low pressure crystal-liquid fractionation that implies a parent composition like that of Apollo 14 sample 14310.

Mineralogy, chemistry and origin of KREEP /potassium, rare earth element and phosphorus/ component in Apollo 12 soil and breccia samples from Ocean of Storms

Structural and mineralogical significance of meteoritic craters, including mineral paragenesis, high pressure polymorphs, microfractures, and quartz lamellae

Optical, X-ray-diffraction and electron-microprobe techniques were used to investigate 0.26 gm of Apollo 14 soil sample 14259. Major element microprobe analyses were made of 470 mineral grains and 388 glass grains. The mineral abundances in the soil are 45% plagioclase, 41% pyroxene, 7% olivine, 3% oxides, 2% K-feldspar; 1% nickel-iron, and less than 1% troilite. The glasses have a wide range of compositions but preferred values are evident and are interpreted as representative of rock types contributing to the soil at the Fra Mauro site. Eleven per cent of the glasses have compositions like those of mare basalts or mare soils and are believed to be mare-derived. Eighty-six per cent of the glasses are equivalent in composition to basalts that have higher Al, and lower Ca/Al and Fe/Mg ratios than mare basalts. The most abundant compositional type is named Fra Mauro basaltic glass and is subdivided into three related types. The other major glass type in the soil corresponds in composition to anorthositic gabbro.

The mineralogy and petrology of sixteen Apollo 15 soil samples from six stations are described together with the mineralogy, petrology, and chemistry of nineteen 4 to 10 mm basaltic lithic particles from nine stations. The lithic samples are classified, and relative abundances of the various rock types in the different samples are determined. The data are used to discuss the origin of the lithic types and their distribution according to selenological terranes. Population studies on particles in the 0.5 to 4 mm size range reveal systematic differences among three selenological terranes corresponding to the Appenine Front, the Mare/Rille, and the ridge or ray locations.