Traçabilité, vieillissement et qualité des huiles essentielles (apport de la veille stratégique)

AIX-MARSEILLE2-BU Pharmacie (130552105) / SudocSudocFranceF

Mobilité des éléments géochimiques dans un bassin sédimentaire clastique, du Protérozoïque à nos jours (le bassin Athabasca (Saskatchewan, Canada))

NANCY/VANDOEUVRE-INPL (545472102) / SudocSudocFranceF

Ion microphrobe CAMECA IMS-3fREE and isotopic U-Pb analyses of uranium oxide.

International audienc

Methodology for rare earth element determinations of uranium oxides by ion microprobe.

International audienc

A Rheological Method to Evaluate the Physical Stability of Highly Viscous Pharmaceutical Oil-in-Water Emulsions

International audienceThe aim of this study was to develop a rheological method to evaluate the stability of highly viscous pharmaceutical emulsions. Thereby, the time devoted to the storage tests could be reduced and manufacturers could save time in optimizing their formulations and manufacturing techniques for topical pharmaceutical forms. The influence of the type of oil and the type of emulsifier on the microstructure of the emulsions was also studied. Materials and Methods. The samples were stored at 25 and at 50-C for 6 months and analysed every month using rheological as well as microscopic techniques. The size and the organization of the droplets within the emulsion were determined by freeze-fracture electron microscopy and optical contrast phase microscopy. Results. A decrease in the rheological parameters was observed for the OC emulsions (BTween/Spanê mulsions made with olive oil) and the BMontanov^emulsions. The rheological measurements showed that the structure of the OC emulsions and that of the emulsions made with the Montanov 82 emulsifier become more brittle when submitted to a shear force. The micrographs obtained by freeze-fracture electron microscopy showed that for OC only the oil droplets arrange in a network structure. Storage tests at 50-C confirmed the rheological assumptions on the stability of emulsions. Conclusion. The study of the effect of shearing on the emulsions allowed quick discrimination between the emulsions according to their stabilities. The rheological tool gave information on the structure of the emulsions and on the aging process

Développement, financement et construction

International audienceCe Tome 5 de la collection "La Mine en France" examine les phases du développement d’un projet minier qui incluent plusieurs étapes faisant suite à la phase initiale d’Exploration : les études de préfaisabilité et de faisabilité, de planification et de financement, et de construction du projet. Ces phases dedéveloppement ne sont entreprises qu’à condition que les résultats d’Exploration se soient avérés prometteurs, c’est-à-dire qu’un gîte minéral ait été reconnu et des ressources préliminaires définies, et que les financements nécessaires à la poursuite aient été obtenus. Si les terminologies, les méthodes et les techniques pour chaque étape varient d’une société à l’autre il existe une progression commune qui se traduit par :• Un niveau de connaissance scientifique et technique de plus en plus élevé ;• Une augmentation des investissements engagés ;• Une estimation de la viabilité du projet de plus en plus précise ;• Une connaissance des enjeux sociaux et environnementaux de plus en plus affinée.À chaque étape correspond une prise de décision sur la poursuite ou non du projet en fonction d’un compromis entre de multiples critères comprenant la technique, la micro et macroéconomie, les aspects socio-environnementaux, le financement et le cadre législatif et fiscal. Aucours de ces processus le risque financier augmente pour les compagnies minières qui investissent de plus en plus sans nécessairement garantie de poursuite

Origin of uranium deposits revealed by their rare earth element signature

International audienc

Mineralogy and geochemistry of the host-rock alterations associated with the Shea Creek unconformity-type uranium deposits (Athabasca Basin, Saskatchewan, Canada). Part 2. Regional-scale spatial distribution of the Athabasca Group sandstone matrix minerals

The spatial distribution of the dominant matrix minerals present in the middle-Proterozoic Athabasca Group sandstone (kaolin, illite, sudoite, dravite, hematite) was studied at a regional scale in the Shea Creek region (Saskatchewan, Canada), in which two epigenetic unconformity-type uranium deposits have been discovered. 3D models of matrix mineral distribution were derived from normative mineral calculations and 3D interpolation using whole-rock geochemical analyses of sandstone samples collected from both mineralized and barren areas. The calculations were constrained by information obtained from petrographic and crystal-chemical clay mineralogical studies on representative samples. The 3D mineral distribution models were compared to the lithostratigraphy and structural features of the Athabasca Group sandstone to ascertain the source and mobility of the main elements involved in the sandstone host-rock alteration processes related to the U mineralization. The distribution of Al is conformable with the lithostratigraphy throughout the studied area, regardless of proximity to basement-rooted structures and U ore bodies. The distribution of illite displays similar features, but the intensity of the illitization of kaolin decreases with increasing distance from the structures and U ore bodies. Hematite bleaching and neoformation of sudoite and dravite were restricted to the vicinity of the fault zones above the U ore bodies. The spatial configurations of the mineral anomalies show that syn-ore fluids flowed from the basement towards the sandstone cover via the fault zones, as described in current metallogenic models. Although Al remained immobile (mass transfer), the anomalous K, B and Mg present in the host-rock alteration haloes were probably imported from the basement rocks (mass transport). Unlike B and Mg, K migrated laterally at least several kilometers from the basement-rooted faults. The mineral distribution models were used to quantify the volume of altered sandstone (10-10km) and the amounts of K, Mg and B which were imported to the alteration haloes above the Shea Creek U ore bodies: 186,000 t of K, 66,000 t of Mg, and 11,000 t of B above the Anne ore body, and 24,000 t of K, 185,000 t of Mg, and a similar 11,000 t of B above the Colette ore body