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Raman spectroscopy, Fourier transform infrared (FTIR) spectroscopy, Atomic absorption spectroscopy (AAS) and X-ray Photoelectron spectroscopy (XPS) have been employed to characterise the surface layer and compound formation during the interaction of n-octanohydroxamate with chrysocolla and malachite surfaces. The flotation response of a single mineral chrysocolla -quartz sand sample and mixed chrysocolla -malachite -quartz sand sample using n-octanohydroxamate collector have been investigated. Recoveries of 95% were achieved in bench-scale flotation testing, with the best Cu grades achieved at pH > 9. Long conditioning times adversely affected flotation performance. Moderate recovery of impurity minerals in the mineral and sand was also observed.

Weak mixing coefficients for D2 and D2–He mixtures at 305.2 and 100.7 K are reported and compared with ab initio quantal calculations. The measurements support but do not provide a critical test of the calculations. Measurements of 50% D2 in Ar at 305.2 K are at variance with the measurements in the pure gas and in mixtures with He and below 20 amagat exhibit an increasing line asymmetry with decreasing density. The results are also at variance with the asymmetries measured in 5% H2 in Ar. PACS No.: 33.70.Jg, 33.20.Fb

Precise and accurate measurements of the Q branch lines of D 2 in D 2 and D 2 -He mixtures at several temperatures and low densities reveal a regular broadening at very low densities but only if allowance is made for departures from the soft-collision model. Above about 2 amagat the broadening becomes anomalous and is consistent with earlier observations. Because of the anomalies, a meaningful comparison between broadening and shifting coefficients and ab initio calculations was not possible. Diffusion constants, as extracted from the data for mixtures, allow us to establish an empirical relation between this diffusion constant and those for pure D 2 and for D 2 infinitely diluted in He. PACS Nos. 33.70Jg and 33.70−W Résumé : Des mesures minutuieuses et précises des lignes de la bande Q du D 2 dans le D 2 et dans des mélanges D 2 -He à plusieurs températures et à basse densité révèlent un élargissement régulier à très basse densité, mais seulement si on s'émancipe du modèles aux collisions douces. Au dessus de 2 amagat, l'élargissement devient anomal et est cohérent avec des mesures antérieures. À cause des anomalies, il n'a pas été possible de faire de comparaison significative entre, d'un côté l'élargissement et le déplacament des coefficients et de l'autre un calcul ab initio. Les constantes de diffusion extraites des données pour les mélanges nous permettent d'établir une relation empirique avec celles pour du D 2 pur et du D 2 infiniment dilué dans He. [Traduit par la rédaction]

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