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The cubic-plus-association equation of state was applied to model the phase behaviour of bitumen/n-alkane systems including saturation pressures, liquid-liquid boundaries, yields, and phase compositions. Yield is defined here as the mass of bitumen in the heavy phase divided by the mass of bitumen in the feed. To implement the model, the bitumen was divided into a set of pseudo-components based on a distillation assay and either the n-pentane insoluble content of the oil (CPA-C5 approach) or the propane insoluble content (CPA-C3 approach). The pseudo-components in the solvent insoluble part of the oil were defined as self-associating components, all other pseudo-components were non-associating. The critical properties and acentric factor for each pseudo-component were determined from established correlations. A set of CPA parameters was then developed to fit the available phase behavior data. The self-associating pseudo-components were assigned a distribution of self-association energies in order to capture the sequential partitioning of asphaltenes to the heavy phase upon solvent addition or in different solvents. Both approaches matched the phase behavior data for mixtures of bitumen with n-pentane and higher carbon number n-alkanes almost to within the experimental error. The CPA-C3 approach also matched the phase behavior data for mixtures of propane and bitumen. The CPA-C5 approach could not match the yield data for propane diluted bitumen but was more straightforward to implement and was less computationally intensive because it employed fewer self-associating components. To apply either approach to another oil, only the self-association energy of the self-associating pseudo-components need be adjusted. The cross-association energy between the solvent and the self-associating pseudo-components must be tuned for any new solvent.

The binary manganese-antimony (Mn-Sb) phase diagram was reinvestigated in the whole composition range using powder-XRD, DTA and SEM-EDX. The phase boundaries and melting temperatures of the ferromagnetic phases MnSb and Mn2Sb were modified by taking into account the new experimental data. Most of the reaction temperatures could be verified within a range of ±10 °C. Nevertheless, a few temperatures had to be revised, such as the eutectic reaction L → β-Mn + Mn 2 Sb at 893 °C and the eutectoid reaction β-Mn → α-Mn + Mn 2 Sb at 718 °C. The previously reported peritectic melting behavior of MnSb could be confirmed. The variation of the lattice parameters of the NiAs-(B8 1 ) type MnSb phase with composition was determined. A revised version of the of the Mn-Sb phase diagram is presented.

Unsteady-state sorption of a vapor or liquid by a polymer is modeled to include the influence of the moving phase boundary associated with the polymer swelling and diffusion-induced convection. A formulation presented clearly elucidates the influence of these two effects on the overall sorption process. Numerical solutions of the model equations indicate the errors that can be induced when swelling or convection are neglected. For most polymer-solvent systems, the influence of the diffusion-induced convection associated with volume changes in mixing can be neglected in the analysis of sorption processes. In contrast, the correction for the moving boundary or swelling of the polymer phase can be quite significant, particularly when a large step change in solvent concentration is considered.

Des essais de cisaillements cycliques, à des températures variant de 360 °C à 460 °C, ont été réalisés sur l'eutectique lamellaire Al-Al2Cu(θ) obtenu par solidification dirigée. La cission appliquée est parallèle aux joints Al/θ et à la direction de croissance. L'expérience indique que la contrainte d'écoulement du matériau correspondant à chaque cycle ne dépend pratiquement que de la température et de la vitesse de charge actuelles du matériau. Le glissement macroscopique g résulte de glissements interfaciaux très localisés, délimitant le plus souvent des paquets de lamelles en nombre pair. Ces glissements interfaciaux sont tous proportionnels à g. L'utilisation d'une loi constitutive analogue à celle de Mukherjee, Bird et Dorn (1969) conduit à un exposant m égal à 0,26 pour la vitesse de glissement g et une énergie d'activation apparente voisine de 128 kJ.mole-1.