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The effect that connate water has on fingers of water penetrating into an oil-wet porous medium is examined. In this context, the connate water appears to have no influence on the width of fingers, but instead causes the fingers to be more irregular than fingers in similar experiments without connate water. The surface wettability, in contrast, does have a marked effect on finger widths. On examine dans cet article les effets de l'eau connée sur la digitation de l'eau dans un milieu poreux mouillable à l'huile. Dans ce contexte l'eau connée ne semble avoir aucune influence sur la largeur des digitations mais rend ces dernières plutôt plus irrégulières que dans le cas des expériences effectuées en absence d'eau connée. Par contre, la mouillabilité de la surface a un effet important sur la largeur des digitations.

The theory of immiscible radial displacement in a Hele-Shaw cell is extended to the case of a porous medium contained between two closely-spaced parallel plates, and experiments are described for the displacement of glycerine by paraffin oil in such a system. Data are presented for the number of fingers, the breakthrough time, and the glycerine recovery, for a range of flowrates varying through three orders of magnitude. Good agreement between theory and experiment is observed. La théorie s'appliquant aux déplacements radiaux dans les cellules Hele-Shaw a été étendue à un système qui consiste en une couche mince de milieux poreux encapsulée entre deux plaques en verre. Dans cet article, on examine les déplacements de la glycérine par de l'huile de paraffine. En faisant varier le débit de l'huile de paraffine dans un intervalle de trois ordres de grandeur, on a étudié les variables telles que le nombre de digitations, le temps de percée et le taux de récupération de la glycérine. On a observé un bon accord entre la théorie et les résultats expérimentaux.

The effects of buoyancy forces on liquid-liquid displacement processes occurring in porous media are important in a variety of practical situations, in particular during the displacement of oil from partially-depleted underground reservoirs by means of aqueous solutions. Most previous studies involving the visualization of water/oil displacements in porous media have been undertaken in horizontal two-dimensional porous medium cells. The objective of the present work was to determine the effects of buoyancy forces; on the fingering pattern and oil recovery by conducting immiscible displacement experiments in two-dimensional consolidated porous medium cells aligned in the vertical plane. In order to obtain a clear understanding of the favourable and unfavourable effects of buoyancy forces, experiments were carried out in three different flow modes, namely horizontal, vertical upward, and vertical downward. As the effects of buoyancy forces are negligible for two-dimensional porous media in the horizontal flow mode, the recoveries obtained in this mode were used as a reference for comparison with those obtained in the two vertical modes. Displacements using five different density ratios were studied. The breakthrough time and percentage oil recovery were measured in each case. The effects of buoyancy forces, viscous forces, and capillary forces, as well as the injection flow rate, were also recorded. The results obtained indicate that the effects of buoyancy forces are very pronounced at low flow rates and low oil/water density ratios, and that even a slight increase in the flow rate causes the buoyancy forces to rapidly become less significant. Les facteurs de flottabilité exercent un effet important sur les déplacements liquide/liquide en milieu poreux dans toute une gamme de situations pratiques, en particulier lorsqu'on veut déplacer l'huile de roches réservoirs partiellement épuisées à l'aide de solutions aqueuses. La plupart des études effectuées jusqu'ici ont fait intervenir la visualisation des déplacements eau/huile en deux dimensions, dans des milieux poreux horizontaux. L'objectif de la présente recherche est de déterminer les effets des facteurs de flottabilité sur le phénomène de digitation et la récupération de l'huile, en effectuant des expériences de déplacements non-miscibles sur des milieux poreux consolidés, bi-dimensionnels, à cellules alignées dans un plan vertical. Pour bien comprendre les effets positifs et négatifs des facteurs de flottabilité, nous avons effectué des expériences avec trois modes d'écoulement différents : horizontal, vertical ascendant et vertical descendant. L'effet des facteurs de flottabilité étant négligeable pour les milieux poreux bi-dimensionnels en cas d'écoulement horizontal, les données de récupération obtenues dans ce cas ont servi de référence pour comparaison avec les données obtenues en cas d'écoulement vertical. L'étude des déplacements a été effectuée avec cinq solutions de densité différente. Dans chaque cas, nous avons mesuré le temps de percée et le pourcentage de récupération de pétrole. Les effets des facteurs de flottabilité, de capillarité et de viscosité ont été enregistrés, ainsi que le débit d'injection. Les résultats obtenus indiquent que les facteurs de flottabilité exercent un effet très prononcé à faible débit et pour une faible densité huile/eau, et que la moindre augmentation du débit entraîne une baisse rapide de cet effet.

Caustic flooding is frequently used to recover acidic oils in secondary and tertiary recovery modes. This study examines the secondary recovery of an acidic oil by alkaline solutions in a water-wet porous medium using a radial geometry. A model porous medium consisting of sintered glass beads sandwiched between two glass plates was employed to visualize the displacement process. The medium was originally saturated with the oil phase, namely paraffin oil (non-reacting system) or paraffin oil doped with 1 wt% linoleic acid (reacting system). The effects of the injection flow rate and the NaOH concentration in the aqueous phase on the displacement pattern were studied experimentally. The volumetric oil recovery at the breakthrough condition was also measured. Dynamic interfacial tension (IFT) measurements for the reacting system were measured in a spinning drop tensiometer. A drastic drop in the IFT occurred as a result of the chemical reaction at the interface between the linoleic acid in the oil phase and the NaOH in the aqueous phase. It was also found that the IFT behavior with respect to time was a function of NaOH concentration with a maximum interfacial activity (minimum IFT) occurring at 0. 1 w% NaOH. Displacement runs showed a significant change in the displacement patterns during secondary recovery for the reacting system compared with those for the non-reacting one. A significant drop in the breakthrough recovery was obtained for the reacting systems, especially at high injection flow rates. The breakthrough recovery of the reacting system was found to be a function of NaOH concentration in the aqueous phase, with a minimum recovery at NaOH concentration of 0. 1 wt%. On a souvent recours à la submersion par des produits alcalins pour récupérer les acides gras dans les modes secondaire et tertiaire. Dans cette étude, on examine la récupération secondaire d'un acide gras par des solutions alcalines dans un milieu poreux imprégné d'eau, de géométrie radiale. Pour visualiser le processus de déplacement, on utilise un milieu poreux constitué de perles de verre fritté placées entre deux plaques de verre. Le milieu est initialement saturé avec la phase huileuse, à savoir l'huile de paraffine (non réactive), ou l'huile de paraffine enrichie de 1 % en poids d'acide linoléique (réactif). On étudie expérimentalement les effets du débit de l'injection et de la concentration en NaOH dans la phase aqueuse sur le schéma du déplacement. On mesure également la récupération en volume d'huile à l'épreuve de la filtration. Des mesures de tension interfaciale (IFT) du système réactif ont été prises à l'aide d'un tensiomètre à goutte tournante. Une chute importante de la tension interfaciale traduit la réaction chimique à l'interface entre l'acide linéoléique de la phase huileuse et la soude NaOH de la phase aqueuse. On a également trouvé que l'évolution de la tension interfaciale IFT par rapport au temps dépendait de la concentration en NaOH, avec une activité interfaciale maximum (IFT minimum) pour une concentration de 0,1 % de NaOH en poids. Les essais de déplacement font apparaître un changement significatif des schémas de déplacement au cours de la récupération secondaire du système réactif par rapport à ceux du système non réactif. Une chute significative de la récupération par filtration est obtenue pour les systèmes réactifs, particulièrement pour les débits d'injection élevés. On a trouvé que la récupération du système réactif variait suivant la concentration de NaOH dans la phase aqueuse, avec une récupération minimum pour 0,1 % de NaOH en poids.

Radial displacement of a non-wetting fluid (paraffin oil) by a wetting fluid (water) was studied in a consolidated porous medium for a wide range of flowrates. The effects of injection flowrate on the displacement pattern were observed photographically, and the volumetric oil recovery at the breakthrough condition was measured. The experimental results indicate that the recovery versus flowrate curve can be divided into three main regions: (1) a capillary regionat low flowrates where capillary forces are dominant; (2) a viscous regionat high flowrates where viscous forces are dominant; and (3) an intermediate stabilized regionwhere capillary and viscous forces are of comparable magnitude. The experimental data for the number of fingers are compared with theoretical predictions and the so-called wettability number is calculated. The results are finally compared with previous data for systems of reversed wettability and the differences, which are very significant, are discussed. On a étudié le déplacement radial d'un fluide non mouillant (l'huile de paraffine) par un fluide mouillant (l'eau) dans un milieu poreux consolidé et pour une large gamme de débit. On a observé photographiquement les effets du débit d'injection sur le modèle de déplacement et mesuré la récupération volumétrique de l'huile en condition de rupture. Les résultats expérimentaux indiquent que l'on peut diviser en trois parties principales la courbe donnant la récupération en fonction du débit : - un domaine capillaire à faible débit où les forces capillaires sont dominantes, - un domaine visqueux à débit élevé où les forces visqueuses sont dominantes, - un domaine intermédiaire stabilisé où les forces capillaires et visqueuses sont de grandeur comparable. On compare les données expérimentales relatives au nombre de digitations avec les prévisions théoriques et on calcule le nombre dit de mouillabilité . Les résultats sont finalement comparés aux données précédentes de systèmes à mouillabilité inverse et on discute de très importantes différences.

International purchasing and supply management (PSM) teams have long faced the visibility and understandability challenges of managing geographically dispersed and culturally distant suppliers. Problems arising from inadequate monitoring and control over suppliers can be attributed to geographical and cultural distance, capability gaps, weak institutions, and supply market dynamism. With transaction costs theory as our lens, we examine how international geographically and culturally distant purchasing and supply management (PSM) teams control emerging economy suppliers with formal management controls. We use interview survey data on 339 international customer-Chinese supplier relationships using supplier perceptions of the extent to which performance measurement and monitoring practices are used by their primary customer in the purchase reorder decision and control. The results demonstrate that the cultural and, to a lesser extent, geographical distance between the customer and the supplier is associated with more extensive use of formal management controls. Also, we find the relationship between geographical or cultural distance and the importance of performance measurement is strengthened for suppliers of complex components. [ABSTRACT FROM AUTHOR]

This study draws on Simons' levers of control model to explore how companies rely on the balanced use of diagnostic and interactive performance measurement systems (PMS) to translate corporate social responsibility (CSR) into superior performance. Data were collected based on a survey data set from 98 CFOs of public listed companies in Iran. The theoretical model was tested using partial least squares structural equation modeling (PLS‐SEM, SmartPLS 3.0), which enjoys minimum demands concerning normality assumptions and sample size. The findings show that CSR is positively associated with PMS and organizational performance. Moreover, CSR is indirectly related to organizational performance through the mediating effect of PMS. This study extends the previous literature by simultaneously incorporating resource orchestration theory in the management accounting and CSR settings. The findings provide further insights into the issue of how adopting proper management control mechanisms (e.g., balanced use of PMS) can support organizations in orchestrating the social, environmental, and economic impacts more effectively. [ABSTRACT FROM AUTHOR]

Successful interorganizational governance requires practices that reduce information asymmetry between supply chain partners and foster collaborative activities. We study one potential practice—suppliers aligning their performance measurement systems with their largest customer's performance priorities. Using survey data collected from face-to-face interviews with executives from over 1,000 electronic components suppliers, we find that suppliers with greater customer-supplier information asymmetry and higher partner interdependence have performance measurement systems that align more with their largest customer's performance priorities. These results are particularly apparent when the exchange involves complex components and when the largest customer represents a greater proportion of supplier sales, suggesting that performance measurement system alignment is of greater value in such situations. We conclude that the performance priorities of large customers play a role in shaping suppliers' management control systems. [ABSTRACT FROM AUTHOR]

This study relies on a unique synthesis of ambidexterity theory and the natural resource orchestration approach to investigate how green intellectual capital elements, namely green human, structural, and relational capital, along with ambidextrous green innovation, trigger a synergy in favor of environmental performance. In particular, this paper primarily aims to test the mediating role of ambidextrous green innovation in the relationship between green intellectual capital and environmental performance. Based on a survey of 105 Iranian public listed companies, the results indicate that green intellectual capital elements are not directly associated with environmental performance. Instead, they influence environmental performance only through the channel of ambidextrous green innovation as a mediating variable. This is the first study to simultaneously embed the resource orchestration theory in the green intellectual capital and ambidexterity literature. The findings of the current study offer new insights into the issue of how organizations gain maximum benefit from the orchestration of their various green assets and capabilities, including green intellectual capital and ambidextrous green innovation. [ABSTRACT FROM AUTHOR]

The administration of home enteral tube feeding (HETF) helps seriously disabled patients. A study in East Anglia, UK, indicated that the uneven district-wise distribution of HETF is possibly due to variations in the available support staff and local expertise. The quality of care was not always in accordance with standards set by the British Association of Parenteral and Enteral Nutrition and the King's Fund report.