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Densities, viscosities, refractive indexes, and surface tensions of a ternary system (tetrahydofuran + 2-propanol + 2,2,4-trimethylpentane) at T = 298.15 K and three constituent binary systems at T = (288.15, 298.15, and 308.15) K were measured at atmospheric pressure. Densities were determined using a vibrating-tube densimeter. Viscosities were measured with an automatic microviscometer based on the rolling ball principle. Refractive indexes were measured using a digital Abbe-type refractometer. Surface tensions were determined by the Wilhelmy-plate method. These results were used to calculate excess molar volumes V E, deviations in the viscosity Δη, deviations in the refractive index Δn D, and deviations in the surface tension Δσ. The calculated quantities of V E, Δη, Δn D, and Δσ were fitted to variable-degree polynomials. The ternary results were compared with the values estimated by different empirical equations of prediction.

During thermal oxidation of silicon, the solute in the original silicon is redistributed between the oxide formed and the unoxidized silicon. The redistribution depends on the segregation coefficient of the solute between the oxide and the silicon, the growth rate constant of the oxide, and the diffusion coefficients of the solute in the oxide and in the silicon. It also depends on the boundary condition existing at the oxide-free space interface. The concentration profile of the redistributed solute is analyzed mathematically and exact solutions are obtained for two cases. In the first case, there is no gain or loss of the solute by the oxide-silicon system through the oxide surface. In the second case, the oxide is in equilibrium with the ambient gas so that the concentration of the solute is a constant at the oxide surface. The results are discussed with special attention to the two most common solutes, boron and phosphorus.

Densities, viscosities, refractive indices, and surface tensions of a ternary system (1,3-dioxolane + 2-propanol + 2,2,4-trimethylpentane) at T = 298.15 K and two binary systems (1,3-dioxolane + 2-propanol and 1,3-dioxolane + 2,2,4-trimethylpentane) at T = (288.15, 298.15, and 308.15) K were measured over the extensive composition range at atmospheric pressure. Densities were determined using a vibrating-tube densimeter. Viscosities were measured with an automatic microviscometer based on the rolling-ball principle. Refractive indices were measured using a digital Abbe-type refractometer. Surface tensions were determined by the Wilhelmy-plate method. The excess molar volumes V E were calculated from the experimental density data. The results are discussed in terms of molecular interactions.

Densities and viscosities were measured for the systems of methanol, ethanol, propan-2-ol, and 2-methylpropan-2-ol separately with a synthetic C6+ mixture at temperatures from 298.15 K to 318.15 K and atmospheric pressure. The synthetic C6+ is a five-component hydrocarbon mixture. Densities were determined using a vibrating-tube densimeter. Viscosities were measured with an automatic Ubbelohde capillary viscometer. The estimated uncertainties are less than ±0.0004 g·cm-3 for density and ±0.8% for viscosity. By considering the six-component mixture as a pseudobinary system, excess volumes and viscosity deviations as a function of mole fraction average were derived, and the computed results were fitted to the Redlich−Kister equation.