[en] It is shown that under the assumption of no intermolecular interaction, the permittivity of a homogeneous linear and isotropic fluid mixture is the sum of the individual permittivities weighted with the mole fractions of the components. For definiteness, a proof is given for gasses under standard temperature and pressure; it is, however, easy to generalize it to other conditions, as well as to liquids, as long as the assumption of no intermolecular interaction is retained. Also, although the proof is given for a binary mixture, it is a simple exercise to extend it to any multicomponent mixture

[en] A local composition model for multicomponent, nonaqueous, liquid mixture shear viscosity has been developed and tested. Only binary equilibrium thermodynamic information is required in addition to pure component data; no mixture viscosity data and no adjustable parameters are used. Predictions have been compared to experimental data obtained from the literature and in this laboratory yielding an average absolute percent deviation of 1.1% for 1n(nuv) for 47 binary systems consisting of 391 points over the entire composition range and 0.75% for seven ternary systems consisting of 63 data points. The data used in the comparison are primarily at 298 K and 1 atm

[en] A model for the packing density of multi-sized grains is presented. For a given mixture, the packing density is expressed as a function of the fractional solid volume of each grain size present. The case of grain sizes continually distributed is derived. Comparison of model predictions with binary, ternary and higher-order mixtures is quite encouraging. (orig.)

[en] We employ the adaptive resolution approach AdResS, in its recently developed Grand Canonical-like version (GC-AdResS) [H. Wang, C. Hartmann, C. Schütte, and L. Delle Site, Phys. Rev. X 3, 011018 (2013)], to calculate the excess chemical potential, μ^ex, of various liquids and mixtures. We compare our results with those obtained from full atomistic simulations using the technique of thermodynamic integration and show a satisfactory agreement. In GC-AdResS, the procedure to calculate μ^ex corresponds to the process of standard initial equilibration of the system; this implies that, independently of the specific aim of the study, μ^ex, for each molecular species, is automatically calculated every time a GC-AdResS simulation is performed

[en] This report provides minimum critical values for various 30-cm water-reflected uranium and plutonium oxide and nitrate aqueous mixtures as calculated by the SCALE CSAS1X sequence using the 238-group ENDF/B-V neutron cross-section library. The minimum values were determined through parametric searches in one-dimensional geometry. The calculations have been performed to obtain the minimum values: critical volume and mass for spheres, critical radius for cylinders, critical thickness for slabs, and minimum critical concentration (infinite geometry) for the following homogeneous mixtures: (1) UO₂-H₂O for 3, 4, 5, 20, and 100 wt % ²³⁵U; (2) UNH for 3, 4, 5, 20, and 100 wt % ²³⁵U; (3) PuO₂-H₂O for 100/0/0, 95/5/0, 90/5/5, 80/10/10, and 71/17/11/1 wt % of ²³⁹Pu/²⁴⁰Pu/²⁴¹Pu(/²⁴²Pu); and (4) PuNH for 100/0/0, 95/5/0, 90/5/5, 80/10/10, and 71/17/11/1 wt % of ²³⁹Pu/²⁴⁰Pu/²⁴¹Pu(/²⁴²Pu). All bounding surfaces were fully reflected by 30 cm of H₂O

No abstract available

[en] Positron annihilation spectra were investigated in the critical region close to the consolute point of ethanol + dodecane mixture. The anomalies of the positron lifetimes and intensities were small, nevertheless it was found that the intensity of short-living components of annihilation spectrum seems to increase close to the critical temperature. (author)

[en] Classical theory of multi-component nucleation [O. Hirschfelder, J. Chem. Phys. 61, 2690 (1974)] belongs to the class of the so-called intractable problems: it requires computational time which is an exponential function of the number of components N. For a number of systems of practical interest with N > 10, the brute-force use of the classical theory becomes virtually impossible and one has to resort to an effective medium approach. We present an effective binary model which captures important physics of multi-component nucleation. The distinction between two effective species is based on the observation that while all N components contribute to the cluster thermodynamic properties, there is only a part of them which trigger the nucleation process. The proposed 2D-theory takes into account adsorption by means of the Gibbs dividing surface formalism and uses statistical mechanical considerations for the treatment of small clusters. Theoretical predictions for binary-, ternary-, and 14-component mixtures are compared with available experimental data and other models

No abstract available

[en] The heat transfer coefficient for nucleate boiling of pure liquids can be determined in many cases by the simple relation h = C X q /SUP n/ . (In nucleate boiling of mixtures with widely varying properties, the concentration gradient close to the heating surface strongly affects the heat transfer. The composition of the mixture is difficult to obtain there. The authors develop simple relations based on experimental values for four different refrigerant-oil mixtures in concentrations from 0.005 to 0.20) the following relation renders best results: h = 0.085 X (exp X (b₁w) + exp X (b₂w)) x q For each kind of oil, however, different values of b₁, b₂ and B have to be used; these are given