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Vous avez des questions? Nous pouvons vous aider. Pour communiquer directement avec un auteur, consultez la première page de la revue dans laquelle son article a été publié afin de trouver ses coordonnées. Si vous n'arrivez pas à les repérer, communiquez avec nous à PublicationsArchive-ArchivesPublications@nrc-cnrc.gc.ca. Questions? Contact the NRC Publications Archive team atPublicationsArchive-ArchivesPublications@nrc-cnrc.gc.ca. If you wish to email the authors directly, please see the first page of the publication for their contact information. NRC Publications Archive Archives des publications du CNRCThis publication could be one of several versions: author's original, accepted manuscript or the publisher's version. / La version de cette publication peut être l'une des suivantes : la version prépublication de l'auteur, la version acceptée du manuscrit ou la version de l'éditeur. NRC Publications Record / Notice d'Archives des publications de CNRC:http://nparc.cisti-icist.nrc-cnrc.gc.ca/eng/view/object/?id=e86f975e-a999-46cb-9d14-894f9eec6d2a http://nparc.cisti-icist.nrc-cnrc.gc.ca/fra/voir/objet/?id=e86f975e-a999-46cb-9d14-894f9eec6d2a Process and EnVironmental Technology, National Research Council of Canada, 1200 Montreal Road, M-12 Ottawa, Ontario K1A 0R6, Canada ReceiVed: April 17, 2005; In Final Form: June 24, 2005 Platinum-ruthenium nanoparticles stabilized within a conductive polymer matrix are prepared using microwave heating. Polypyrrole di(2-ethylhexyl) sulfosuccinate, or PPyDEHS, has been chosen for its known electrical conductivity, thermal stability, and solubility in polar organic solvents. A scalable and quick two-step process is proposed to fabricate alloyed nanoparticles dispersed in PPyDEHS. First a mixture of PPyDEHS and metallic precursors is heated in a microwave under reflux conditions. Then the nanoparticles are extracted by centrifugation. Physical characterization by TEM shows that crystalline and monodisperse alloyed nanoparticles with an average size of 2.8 nm are obtained. Diffraction data show that crystallite size is around 2.0 nm. Methanol electro-oxidation data allow us to propose these novel materials as potential candidates for direct methanol fuel cells (DMFC) application. The observed decrease in sulfur content in the polymer upon incorporation of PtRu nanoparticles may have adversely affected the measured catalytic activity by decreasing the conductivity of PPyDEHS. Higher concentration of polymer leads to lower catalyst activity. Design and synthesis of novel conductive polymers is needed at this point to enhance the catalytic properties of these hybrid materials.

/npsi/ctrl?action=rtdoc&an=8934308&lang=en http://nparc.cisti-icist.nrc-cnrc.gc.ca/npsi/ctrl?action=rtdoc&an=8934308&lang=frAccess and use of this website and the material on it are subject to the Terms and Conditions set forth at http://nparc.cisti-icist.nrc-cnrc.gc.ca/npsi/jsp/nparc_cp.jsp?lang=en NRC Publications Archive Archives des publications du CNRCThis publication could be one of several versions: author's original, accepted manuscript or the publisher's version. / La version de cette publication peut être l'une des suivantes : la version prépublication de l'auteur, la version acceptée du manuscrit ou la version de l'éditeur. For the publisher's version, please access the DOI link below./ Pour consulter la version de l'éditeur, utilisez le lien DOI ci-dessous.http://dx.doi.org/10.1021/ef8002203 Energy & Fuels, 22, 5, pp. 3174-3193, 2008 Ottawa, Ontario K1J 7C4, Canada, and Syncrude Canada Ltd., Edmonton Research Centre, 9421-17 AVenue, Edmonton, Alberta T6N 1H4, Canada ReceiVed March 28, 2008. ReVised Manuscript ReceiVed June 13, 2008 An X-ray diffraction (XRD) methodology has been developed for characterizing clays in unextracted oil sands. Application of the new technique to five estuarine and five marine ores directly identified three clay mineral properties that may impact bitumen recovery: (1) The specific surface area of illite was significantly greater for four oil sand ores identified as problematic in batch extraction unit tests. (2) The correlation of illite/kaolinite XRD peak area ratios with bitumen recovery produced a processability classification similar to that proposed in earlier work. (3) Significant amounts of chlorite, as measured by XRD, were observed only in marine oil sands; this may provide a means to distinguish marine from estuarine ores. A combination of XRD analysis on separated clays and laser diffraction determination of clay contents provided a quantitative estimate for the illite and kaolinite contents of the oil sands. Also, the contribution from ultrathin illite and kaolinite for each oil sand (i.e., the mass fractions of illite and kaolinite with crystallite thicknesses of 1-3 composite layers) was determined. This methodology thus provides a direct method for the determination of the ultrafines content in unextracted oil sands and obviates the necessity for the time-consuming wet chemistry technique for separation of this component. For the 10 oil sands analyzed here, ultrathin crystallites occurred almost entirely in the illite clay fraction. The amount of ultrathin illite was critical and closely matched the ultrafines concentration required to cause sludging (gelation) in the primary separation vessel, with concomitant loss of bitumen recovery during extraction.

The chemical composition of green and roasted coffee was reviewed in an attempt to correlate chemical changes which occur during roasting with the formation of nonvolatile flavors. Examination of free and combined amino acids indicate that arginine, cystein, lysine, and serine are markedly destroyed during roasting. The carbohydrates also undergo marked changes-i.e., sucrose and arabinogalactan are destroyed in proportion to degree of roast. Even though the soluble mannan increases with roast, the mannose content of the holocellulose fraction decreases under the same conditions. The acids in green and roasted were examined in greater detail and methods for their quantitative analysis were described. Volatile, nonvolatile, and phenolic acids all decreased with increased roasting time. Chlorogenic acid, a major component of the acids, can be used to measure

Résumé -Pétroles bruts canadiens : étude comparative des fractions SARA à partir d'une technique de séparation HPLC modifiée -Ces dernières années, une réduction mondiale des réserves de pétrole conventionnel pouvant être exploitées a amené à une augmentation des activités d'exploration et de production des pétroles bruts les plus lourds. Au Canada, il a été demandé aux unités de valorisation d'étudier les pétroles lourds et les bitumes provenant des sables bitumineux, plus accessibles mais plus difficiles à exploiter. Afin d'améliorer les conditions de fonctionnement des installations et d'évaluer leur impact sur l'environnement, une connaissance approfondie de la structure moléculaire et du comportement du pétrole source est nécessaire. Les problèmes liés aux hydrotraitements des fractions riches en azote sont particulièrement préoccupants. L'approche utilisée ici implique la séparation d'une série de divers pétroles bruts canadiens (bitumes provenant des sables bitumineux et pétroles lourds et conventionnels) ayant des teneurs en asphaltènes et maltènes variables, suivie d'un fractionnement supplémentaire des maltènes au moyen de la Chromatographie en Phase Liquide à Haute Performance (HPLC). Cette approche diffère de la séparation conventionnelle SARA (saturés, aromatiques, résines et asphaltènes) car les multiples fractions sont facilement séparées sur la base des différences de polarité et fournissent de ce fait des informations plus détaillées sur la répartition des classes de composants. Les fractions séparées peuvent être caractérisées au moyen de différentes méthodes analytiques, y compris : chromatographie par perméation de gel (GPC) pour déterminer le poids moléculaire moyen, le calcul de paramètres moléculaires en utilisant les analyses CHNS en association avec la spectroscopie 1 H et 13 C NMR et l'analyse XPS de groupes chimiques au moyen de la déconvolution de pic. Les bitumes contiennent moins de saturés mais plus de résines et d'asphaltènes que tous les autres pétroles lourds testés. A l'inverse, le pétrole conventionnel est associé à un contenu en saturés plus élevé et à la quantité de résines et d'asphaltènes la moins importante. Les rendements en fractions aromatiques provenant de différentes sources sont tous situés dans une gamme relativement étroite. Il est remarquable que les fractions SARA de chaque pétrole aient des propriétés moyennes en masse relativement voisines. Toutes les fractions résines contenaient plus de 40 % de l'azote total, c'est-à-dire plus que les quantités contenues dans les fractions correspondantes d'asphaltène. On a observé, pour les sous-fractions de résines, des différences relativement moins importantes entre les poids moléculaires, les ratios H/C atomiques et l'aromaticité (C ar ). La différence substantielle dans le comportement de l'élution HPLC pour ces sousfractions semble pouvoir être attribuée à la distribution asymétrique des composants azotés polaires pour

Adsorption of hydrocarbon components, particularly by clay minerals, has an important influence on the recovery of conventional oil from reservoir rocks. In the same vein, biwetted clay particles have been associated with bitumen losses during processing of surface-mined oil sands. In this work, we examined four oil sands with very different batch-extraction unit (BEU) bitumen recovery profiles. Bitumen-free solids from these ores were subjected to supercritical fluid extraction with methanol to separate quantitatively any toluene-insoluble, residual organic matter. The yield of extract correlated well with the amounts of solids in the fine (<44 μm) and clay (<3 μm) size fractions as well as with the concentrations of kaolinite and illite present in the oil sands ores. It is generally assumed that organic matter adsorbed by reservoir solids is asphaltic in origin; however, in the results discussed here, the compositional and structural analysis of the methanol extracts showed more similarities to the resin component of bitumen. Also, in comparison to other bitumen saturates, aromatics, resins, and asphaltenes (SARA) fractions, the extracts from each oil sands were somewhat enriched with pyridines, sulphoxides, and sulphones. We argue that the physicochemical properties of the residual organic matter separated by supercritical extraction strongly influence the wettability of solids in the ores through adsorption onto clay minerals. We suggest that this mechanism is a prerequisite for the formation of biwetted clay particles capable of stabilizing emulsified bitumen-in-water droplets that are too small to be successfully recovered by flotation.

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