115 research outputs found
Le dĂ©voilement de soi Ă lâĂ©preuve du numĂ©rique : cas de SOS AmitiĂ©
Le projet de ce propos est de rendre compte des conditions et dynamiques du dĂ©voilement de soi via le numĂ©rique, et de la reconfiguration de la communication interpersonnelle quâil implique, Ă partir du cas spĂ©cifique de lâassociation SOS AmitiĂ©. Comment lâĂ©crit transforme-t-il les modalitĂ©s de dĂ©voilement de soi ? Dans quelle mesure la relation Ă©coutant-appelant se redĂ©finit-elle ? Comment saisir la complexitĂ© dâune situation par le seul Ă©crit, sans disposer de la palette dâindices pourvue par lâĂ©change tĂ©lĂ©phonique ? Lâimplication des Ă©coutants en est-elle assĂ©chĂ©e ? Au demeurant, quel est le rĂŽle de la mĂ©diation numĂ©rique dans la rĂ©ception et lâentendement des rĂ©cits de lâintimitĂ©Â ? Les mĂ©canismes en jeu comprennent aussi bien le canal de communication qui redĂ©finit lâacte de dĂ©voilement de soi que les dynamiques relationnelles, et le rĂ©cepteur qui voit ses pratiques et habitudes bouleversĂ©es. Au-delĂ de dĂ©gager les implications du mĂ©dium numĂ©rique dans les espaces dâĂ©coute, la perspective dĂ©veloppĂ©e ici consiste, Ă travers une dĂ©marche dâanalyse des pratiques dĂ©crites dans les rĂ©cits dâexpĂ©rience, Ă comprendre les dynamiques de fonctionnement dâun rĂ©cepteur de rĂ©cits de vie. Ce qui intĂ©resse en prioritĂ© ce sont les modalitĂ©s dâinflĂ©chissement des conditions matĂ©rielles, psychologiques et relationnelles du point de vue du rĂ©cepteur.The purpose of this article is to give an account of the conditions and dynamics of self-disclosure via digital device, and of the reconfiguration of the interpersonal communication that it implies, starting from the specific case of the SOS AmitiĂ© association. How does writing transform the ways of self-disclosure? To what extent is the listening-calling relationship redefined? How to understand the complexity of a situation by the only writing, without having the palette of clues provided by the telephone exchange? Has the involvement of listeners dried up? What is the role of digital mediation in the reception and understanding of stories of intimacy? The mechanisms involved include both the communication channel, which redefines the act of self-disclosure and relational dynamics, and the receiver who sees his practices and habits disrupted. Beyond identifying the implications of the digital medium in listening spaces, the perspective developed here consists, through an approach of analysis of the practices described in the accounts of experience, of understanding the dynamics of the functioning of a receiver life stories. What interests in priority are the modalities of inflection of material, psychological and relational conditions from the point of view of the receiver
Assessing social and environmental links in development strategies for Cameroon: A process approach to sustainability
No Abstrac
Essays in theoretical and applied macroeconomics
Cette theÌse sâarticule autour de trois chapitres indeÌpendants qui sâinscrivent dans les champs de la macroeÌconomie, de lâeÌconomie moneÌtaire et de la finance internationale. Dans le premier chapitre, je construis un modeÌle neÌo-keynesien dâeÌquilibre geÌneÌral sous incertitude pour examiner les implications de la production domestique des meÌnages pour la politique moneÌtaire. Le modeÌle proposeÌ permet de reconcilier deux faits empiriques majeurs: la forte sensibiliteÌ du produit inteÌrieur brut aux chocs moneÌtaires (obtenue aÌ partir des modeÌles VAR), et le faible degreÌ de rigiditeÌ nominale observeÌ dans les micro-donneÌes. Le deuxieÌme chapitre eÌtudie le role de la transformation structurelle (reÌallocation de la main dâoeuvre entre secteurs) sur la volatiliteÌ de la production aggregeÌe dans un panel de pays. Le troisieÌme chapitre quant aÌ lui met en exergue lâimportance de la cartographie des eÌchanges commerciaux pour le choix entre un reÌgime de change fixe et lâarrimage aÌ un panier de devises.
"Household Production, Services and Monetary Policy" (Chapitre 1) part de lâobservation selon laquelle les meÌnages peuvent produire aÌ domicile des substituts aux services marchands, contrairement aux biens non durables quâils acquieÌrent presque exclusivement sur le marcheÌ. Dans ce contexte, ils proceÌdent aÌ dâimportants arbitrages entre produire les services aÌ domicile ou les acquerir sur le marcheÌ, deÌpendamment des changements dans leur revenu. Pour examiner les implications de tels arbitrages (qui sâaveÌrent eÌtre importants dans les micro-donneÌes) le secteur domestique est introduit dans un modeÌle neÌo-keyenesien dâeÌquilibre geÌneÌral sous incertitude aÌ deux secteurs (le secteur des biens non durables et le secteur des services) autrement standard. Je montre que les firmes du secteur des services sont moins enclin aÌ changer leurs prix du fait que les meÌnages ont lâoption de produire soit meÌme des services substituts. Ceci se traduit par la preÌsence dâun terme endogeÌne suppleÌmentaire qui deÌplace la courbe de Phillips dans ce secteur. Ce terme croit avec le degreÌ de substituabiliteÌ qui existe entre les services produits aÌ domicile et ceux acquis sur le marcheÌ. Cet accroissement de la rigiditeÌ nominale amplifie la sensibiliteÌ de la production reÌelle aux chocs moneÌtaires, notamment dans le secteur des services, ce qui est compatible avec lâeÌvidence VAR selon laquelle les services de consommation sont plus sensibles aux variations de taux dâinteÌreÌt que les biens non durables.
"Structural Transformation and the Volatility of Aggregate Output: A Cross-country Analysis" (Chapitre 2) est baseÌe sur lâeÌvidence empirique dâune relation neÌgative entre la part de la main dâoeuvre alloueÌe au secteur des services et la volatiliteÌ de la production aggreÌgeÌe, meÌme lorsque je controÌle pour les facteurs tels que le deÌveloppement du secteur financier. Ce resultat aggregeÌ est la conseÌquence des deÌveloppements sectoriels: la productiviteÌ de la main dâoeuvre est beaucoup plus volatile dans lâagriculture et les industries manufacturiĂšres que dans les services. La production aggregeÌe deviendrait donc meÌcaniquement moins volatile au fur et aÌ mesure que la main dâoeuvre se deÌplace de lâagriculture et de la manufacture vers les services. Pour eÌvaluer cette hypotheÌse, je calibre un modeÌle de transformation structurelle aÌ lâeÌconomie ameÌricaine, que jâutilise ensuite pour geÌneÌrer lâallocation sectorielle de la main dâoeuvre dans lâagriculture, lâindustrie et les services pour les autres pays de lâOCDE. Dans une analyse contre-factuelle, le modeÌle est utlisĂ© pour restreindre la mobiliteÌ de la main dâoeuvre entre secteurs de façon endogeÌne. Les calculs montrent alors que le deÌplacement de la main dâoeuvre vers le secteur des services reÌduit en effet la volatiliteÌ de la production aggregeÌe.
"Exchange Rate Volatility under Alternative Peg Regimes: Do Trade Patterns Matter?" (Chapitre 3) est une contribution aÌ la litterature eÌconomique qui sâinteresse au choix entre divers regimes de change. Jâutilise les donneÌes mensuelles de taux de change bilateÌraux et de commerce exteÌrieur entre 1980 et 2010 pour les pays membre de lâUnion Economique et MoneÌtaire Ouest Africaine (UEMOA). La monnaie de ces pays (le franc CFA) est arrimeÌe au franc Francais depuis le milieu des anneÌes 40 et aÌ lâeuro depuis son introduction en 1999. Au moment de lâarrimage initial, la France eÌtait le principal partenaire commercial des pays de lâUEMOA. Depuis lors, et plus encore au cours des dix dernieÌres anneÌes, la cartographie des eÌchanges de lâunion a significativement changeÌ en faveur des pays du groupe des BICs, notamment la Chine. Je montre dans ce chapitre que lâarrimage aÌ un panier de devises aurait induit une volatiliteÌ moins pronnonceÌe du taux de change effectif nominal du franc CFA au cours de la deÌcennie eÌcouleÌe, compareÌ aÌ la pariteÌ fixe actuelle. Ce chapitre, cependant, nâaborde pas la question de taux de change optimal pour les pays de lâUEMOA, un aspect qui serait inteÌressant pour une recherche future.This thesis includes three independent essays in the fields of macroeconomics, monetary economics and international finance. In the first essay, I build a new Keynesian DSGE model to examine the implications for monetary policy of household production. The proposed theory helps reconcile the relatively strong response of output to monetary policy shocks as suggested by VAR-based evidence and the low degree of price rigidity found in micro data. The second essay analyzes the role of structural transformation (the reallocation of labor across sectors overtime) in shaping the volatility of aggregate output across countries. Finally, the third essay illustrates the importance of trade patterns in choosing between a single currency peg and a peg to a composite basket of currencies.
âHousehold Production, Services and Monetary Policyâ (Chapter 1) builds on the observation that consumer services (unlike consumer nondurable) have close substitutes at home. Households may therefore switch between consuming home and market service as the real wage (the opportunity cost of working at home) changes. To study the implications of this arbitrage for monetary policy, I embed a household sector into an otherwise standard two-sector (a nondurable good sector and a service sector) new Keynesian DSGE model. The fact that households are able to produce services at home makes service sectorâs firms more reluctant to change their price. This translates into an extra endogenous shift term in the new Keynesian Phillips that is increasing with the extent of substitutability between home and market services. This increased nominal rigidity endogenously amplifies the output response to monetary policy shock, especially in the service sector, which is consistent with VAR-based evidence in the paper that consumer services are more interest-rate sensitive than consumer nondurables.
âStructural Transformation and the Volatility of Aggregate Output: A Cross-country Analysisâ (Chapter 2) is based on the evidence of a negative relationship between the employment share of the service sector and the volatility of aggregate output, which I obtain after controlling for several factors (including the level of financial development). This
aggregate result is driven by sectoral labor productivity differentials: Labor productivity is substantially more volatile in agriculture and manufacturing than in services. Aggregate output would therefore become mechanically more stable as labor shifts away from agriculture and manufacturing, and toward the service sector. To quantify this conjecture, I first calibrate a model of structural transformation (secular reallocation of labor across sectors) to the U.S. economy, which I use to match the time path of labor shares in agriculture, manufacturing and services across OECD countries. The model is subsequently used to conduct a set of counterfactual experiments in which labor is endogenously constrained from moving across sectors. Computations suggest that the shift of labor toward the services sector is indeed volatility-reducing.
âExchange Rate Volatility under Alternative Peg: Do Trade Patterns Matter?â (Chapter 3) is a contribution to the literature on the choice of exchange rate regimes. I use monthly bilateral exchange rate and external trade data from 1980 to 2010 for the member countries of the Western African and Monetary Union (WAEMU). These countries have their common currency (the CFA franc) pegged to the French franc since the mid-40s and to the euro since its introduction in 1999. At the time of the initial peg arrangement, France accounted for most of the external trade of WAEMU countries. Since then, and more notably since the early 2000s, the trade patterns of these countries shifted briskly away from France and other Euro area countries and towards the BICs (China in particular). The chapter finds that a peg to a composite basket of currencies would have led to a less volatile effective exchange rate over the last decade compare to the current hard peg. This chapter, however, does not derive an optimal exchange rate for WAEMU countries, which is an important area for further research
Antifungal activity and acute toxicity of stem bark extracts of Drypetes Gossweileri S. Moore-Euphorbiaceae from Cameroon
Drypetes gossweilleri S. Moore is a plant used in traditional medicine in Cameroon. The antifungal properties of its stem-bark crude extract and fractions DG1, DG2, DG3, DG4, DG5, DG6, DG7, DG8 and DG9 were assayed by agar and broth dilution methods on solid and liquid media against C. Krusei, C. albicans, C. glabrata, T. mentagerophytes, M. langeroinii, M. gypeum, M. audouini, T. rubrum, T. soudanense, T. terrestre, A. flavus and A. niger. The results revealed a substantial antifungal effect with minimal inhibitory concentrations ranging respectively from 24.11ÎŒg/ml to 1562ÎŒg/ml for yeasts and from 3125ÎŒg/ml to 12500ÎŒg/ml for filamentous fungi. Among the fractions, fraction DG4 exerted the highest antifungal activity. Moreover, no toxic effect was noticed in male and female albinos Wistar rats treated per os with the crude stem barkâs extract of Drypetes gossweileri at a dose up to 12g/kg of body weight. The phytochemical screening of the crude extract and fractions showed the presence of alkaloids, phenols, flavonoids, saponins, anthocyanines, anthraquinones, sterols, lipids and essential oils. Therefore, Drypetes gossweileri may be safe as phytomedecine for the treatment of fungal infections.Key words: Antifungal activity, Drypetes gossweileri, acute toxicity
Role of Cations in the Methane/Carbon Dioxide Partitioning in Nano- and Mesopores of Illite Using Constant Reservoir Composition Molecular Dynamics Simulation
We performed constant reservoir composition molecular dynamics (CRC-MD) simulations at 323 K and 124 bar to quantitatively study the partitioning of fluid species between the nano- and mesopores of clay and a bulk reservoir containing an equimolar mixture of CO2 and CH4. The results show that the basal (001) and protonated edge (010) surfaces of illite both demonstrate a strong preference for CO2 over CH4 adsorption; that the (001) surfaces show a stronger preference for CO2 than the (010) surfaces, especially with K+ as the exchangeable cation; and that the structuring of the near-surface CO2 by K+ is stronger than that by Na+. The protonated (010) surfaces have a somewhat greater preference for CH4, with the concentration near them close to that in the bulk fluid. The effects of the surfaces on the fluid composition extend to approximately 2.0 nm from them, with the fluid composition at the center of the pore becoming essentially the same as the bulk composition at a pore thickness of âŒ5.7 nm. The preference of nano- and mesopores bounded by clay minerals for CO2 over CH4 suggests that injection of CO2 into tight reservoirs is likely to displace CH4 into larger pores, thus enhancing its production
Modélisation moléculaire de l'hydratation, de la structure, et de la mobilité des ions et de l'eau dans l'espace interfoliaire et à la surface d'une argile smectitique
L Ă©tude de l adsorption et de la mobilitĂ© des ions dans les argiles est importante pour mieux apprĂ©hender de nombreux processus gĂ©ochimiques et environnementaux, de mĂȘme que pour prĂ©dire le comportement des radionuclĂ©ides dans les conditions du stockage gĂ©ologique. A cause de leurs tailles trĂšs petites (< 2 m), il n est pas toujours Ă©vident d Ă©tudier les argiles Ă l aide des mĂ©thodes et techniques expĂ©rimentales existantes. L une des alternatives Ă ce problĂšme consiste alors Ă utiliser la modĂ©lisation molĂ©culaire pour les Ă©tudier. En plus de leurs tailles fines, les argiles prĂ©sentent Ă©galement des structures complexes, qui peuvent survenir en raison de la multiplicitĂ© de possibilitĂ©s de distributions et d arrangements des substitutions isomorphiques dans leurs couches. Il a Ă©tĂ© clairement dĂ©montrĂ© qu il existe une corrĂ©lation entre la distribution des substitutions dans les couches des argiles et les propriĂ©tĂ©s de ces derniĂšres. En revanche, ceci reste Ă dĂ©montrer en ce qui concerne l arrangement de ces substitutions dans les couches de l argile. Dans ce travail, la modĂ©lisation molĂ©culaire est utilisĂ©e pour dĂ©terminer et comparer les propriĂ©tĂ©s d hydratation, ainsi que la structure et la mobilitĂ© des ions (Li , Na , K , Rb , Cs , Mg , Ca , Sr , Ba , Ni , UO ) et de l eau dans l espace interfoliaire de trois modĂšles de montmorillonite, diffĂ©rents entre eux par l arrangement des substitutions isomorphiques dans les couches de l argile.L adsorption et la diffusion des cations citĂ©s plus haut et de l eau sont Ă©galement Ă©tudiĂ©es Ă la surface de la montmorillonite et les rĂ©sultats sont comparĂ©s Ă ceux obtenus dans l espace interfoliaire Ă 298 K et Ă 363 K. Les rĂ©sultats obtenus dans ce travail s accordent bien avec les observations expĂ©rimentales, et font ressortir une corrĂ©lation plus ou moins importante entre le modĂšle d argile utilisĂ© et le type de propriĂ©tĂ© calculĂ©e. Cette corrĂ©lation dĂ©pend Ă©galement de la nature du cation prĂ©sent dans la structure de la montmorillonite et de sa teneur en eau.The study of adsorption and ion mobility in clay minerals is important for a better understanding of many geochemical and environmental processes, as well as to predict the behavior of radionuclides in geological storage conditions. Because of their very small size (<2 m), it is not always easy to study clays by using the existing experimental methods and techniques. One alternative to this issue is to use computational molecular modeling to carry out clay studies. In addition to their tiny size, clays minerals also have complex structures, which can appear due to various possibilities in the distribution and arrangement of isomorphic substitutions in their layers. It has been clearly demonstrated that there is a strong correlation between the distribution of substitutions in the clay layers and their properties. However, this remains to be shown regarding the arrangement of the substitutions in the layers of the clay. In this work, computational molecular modeling techniques are used to determine and compare the hydration properties, as well as the structure and mobility of ions (Li , Na , K , Rb , Cs , Mg , Ca , Sr , Ba , Ni ,UO ) and water in the interlayer space of the three models of montmorillonite, that differ from each other by the arrangement of isomorphic substitutions in the clay layers.The adsorption and diffusion of the previously listed cations and water are also studied on the surface of montmorillonite clay and the results are compared to those obtained in the interlayer space both at 298 K and at 363 K. The data generated in this work agree well with experimental observations, and show a more or less significant correlation between the clay model used and the type of property calculated.NANTES-ENS Mines (441092314) / SudocSudocFranceF
Performances zootechniques du poulet de chair soumis à un régime à base de résidus de semoule de manioc supplémenté par la spiruline (Spirulina platensis)
Cette Ă©tude a Ă©tĂ© rĂ©alisĂ©e pour Ă©valuer les performances zootechniques dâun rĂ©gime alimentaire Ă base de rĂ©sidus de semoule de manioc supplĂ©mentĂ©s par la spiruline chez les poulets de chair. Trois (03) groupes de poussins de souche Arbor Acres soumis aux rations tĂ©moins supplĂ©mentĂ©es ou non par la spiruline ont Ă©tĂ©Â comparĂ©s Ă neuf (09) autres groupes soumis aux rations dans lesquelles le maĂŻs a Ă©tĂ© substituĂ© par les rĂ©sidus de semoule de manioc aux taux de 50, 75, et 100% et supplĂ©mentĂ©s par 0,5 ou 1% de spiruline. Les principaux rĂ©sultats ont montrĂ© que tous les paramĂštres de croissance se dĂ©tĂ©riorent avec le taux croissant dâincorporation de rĂ©sidus de semoule de manioc supplĂ©mentĂ©s ou non par la spiruline. Lâindice de consommation a augmentĂ©Â de lâordre de 10; 10 et 15% respectivement avec 50, 75 et 100% de substitution du maĂŻs dans la ration. Le rendement carcasse, le poids relatif de la tĂȘte, des pattes, du foie, du coeur, du pancrĂ©as et de la graisse abdominale Ă©volue en dents de scie dâun traitement Ă lâautre. Les rĂ©sidus de semoule de manioc peuvent avantageusement ĂȘtre supplĂ©mentĂ©s par la spiruline au taux de 0,5% dans lâaliment des poulets de chair.© 2015 International Formulae Group. All rights reserved.Mots clĂ©s: MaĂŻs, manioc, poulets de chair, spirulineEnglish Title:  Zootechnical performances of broiler chickens fed on Spirulina platensis-supplemented cassava root waste based dietEnglish AbstractThis study investigated the growth performances of broiler chickens fed on spirulina-supplemented cassava root waste based diet. Three (03) groups of Abor Acres chicks fed on control diets supplemented or not with spirulina were compared to nine (09) other groups fed on diets in which 50, 75 and 100% of maize were replaced by cassava root waste supplemented or not with 0.5 and 1% spirulina in a completely randomized design. Results revealed that growth parameters including feed intake, weight gain and feed conversion ratio  (FCR) depressed with increasing level of cassava root waste in the diet. FCR was poorer by 10, 10 and 15% respectively with 50, 75 and 100% of maize replaced with cassava root waste. Nevertheless, supplementing with spirulina, irrespective to the level of cassava root waste inclusion, demonstrated a production advantage. Carcass yield and relative weight of organs varied from one experimental diet to another. In conclusion, cassava root waste can be beneficially supplemented with spirulina at 0.5% in broiler diets.© 2015 International Formulae Group. All rights reserved.Keywords: Broiler chickens, cassava, maize, spirulin
Phytochemical analysis and antifungal property of Mallotus oppositifolius (Geiseler) MĂŒll.Arg. (Euphorbiaceae)
The emergence of resistant fungi to available drugs highlights the need for new antifungal drugs. The present study aimed to evaluate the antifungal activity of the isolated compounds, fractions and crude extract from the leaf of Mallotus oppositifolius (Geiseler) MĂŒll. Arg. Three pure compounds labelled 1-3 were isolated from the methylene chloride / methanol (1/1) extract of the leaf of this plant using chromatography techniques. These compounds were identified using analytical spectroscopic methods as betulinic acid (1), quercetine (2) and quercitin (3). The crude extract, fractions and compounds were tested against pathogenic yeasts (Candida albicans, Candida glabrata, Candida krusei) and dermatophytes (Trichophyton rubrum, Trichophyton soudanense, Microsporum audouinii, Microsporum langeronii) using agar well diffusion and dilution methods. The safety of the crude extract was studied on Wistar rats according to the WHO guidelines. The minimal inhibitory concentration (MIC) values ranged from 48 to 781 ÎŒg/ml against yeasts for crude extract and fractions, and 1.86 to 25000 ÎŒg/ml against dermatophytes for pure compounds, fractions and crude extract. The antifungal activity of pure compounds was not determined against yeasts. The crude extract of leaf was found to be safe in rat at up to 12 g/kg. The results achieved supported the traditional use of Mallotus oppositifolius leaf for the treatment of fungal infections.Keywords: Mallotus oppositifolius, antifungal activity, safety, phytochemical screening
Anti-yeast activity of extracts and fractions from Uvariodendron calophyllum (Annonaceae)
The resistance to available antifungals highlights the urgent need for innovative drugs to treat yeasts infections. This study aimed at evaluating the activity of extracts and fractions from Uvariodendron calophyllum against pathogenic yeasts. The ethanolic and aqueous extracts obtained by maceration were liquidliquid- partitioned using organic solvents and screened against isolates of Candida albicans, Candida glabrata, Candida parapsilosis, Cryptococcus neoformans and Candida albicans reference strains NR-29445, NR-29444, NR-29451, and NR-29450 from BEI Resources using the broth micro-dilution method. Time kill kinetic, inhibition of germ-tube, filamentation and chlamydosporulation, and biofilm formation were assessed using the best sub-fraction. Overall, the most interesting sub-fraction (FS: 237â253) showed an MIC value of 0.0625 mg/mL with cidal effect against C. albicans NR-29450 and NR-29445 at 0.25 mg/mL after 12-16 hours and 24 hours respectively. Moderate inhibitory effects were observed at 0.25 mg/mL against germ-tube formation, filamentation and chlamydosporulation of all C. albicans strains. Also, very moderate inhibition of biofilm formation by C. albicans NR-29450 at 0.25 mg/mL was obtained. The results obtained support U. calophyllum as a potential source of compounds with anti-yeast activity. Further studies will confirm its potential as source of anti-yeast drugs.© 2015 International Formulae Group. All rights reserved.Keywords: Uvariodendron calophyllum, anti-yeasts activity, time kill kinetics, biofil
Understanding methane/carbon dioxide partitioning in clay nano- and meso-pores with constant reservoir composition molecular dynamics modeling
The interactions among fluid species such as H2O, CO2, and CH4 confined in nano- and meso-pores in shales and other rocks is of central concern to understanding the chemical behavior and transport properties of these species in the earth's subsurface and is of special concern to geological C-sequestration and enhanced production of oil and natural gas. The behavior of CO2, and CH4 is less well understood than that of H2O. This paper presents the results of a computational modeling study of the partitioning of CO2 and CH4 between bulk fluid and nano- and meso-pores bounded by the common clay mineral montmorillonite. The calculations were done at 323 K and a total fluid pressure of 124 bars using a novel approach (constant reservoir composition molecular dynamics, CRC-MD) that uses bias forces to maintain a constant composition in the fluid external to the pore. This purely MD approach overcomes the difficulties in making stochastic particle insertion-deletion moves in dense fluids encountered in grand canonical Monte Carlo and related hybrid approaches. The results show that both the basal siloxane surfaces and protonated broken edge surfaces of montmorillonite both prefer CO2 relative to CH4 suggesting that methods of enhanced oil and gas production using CO2 will readily displace CH4 from such pores. This preference for CO2 is due to its preferred interaction with the surfaces and extends to approximately 20 Ă
from them
- âŠ