La microporosité représente jusqu'à 95% de la porosité totale des réservoirs à hydrocarbures et des aquifères dans les calcaires crétacés du Moyen-Orient. Dans ces sédiments microporeux, la porosité est modérée à excellente (jusqu'à 35%), tandis que la perméabilité est faible à modérée (jusqu'à 190mD). A l'inverse, mes faciès microporeux peuvent former des niveaux denses, avec de très faibles porosité et perméabilité (respectivement 2–8% et 0,01–2mD). Dans ce travail, les échantillons proviennent essentiellement de la Formation Mishrif (Cénomanien), mais aussi de la Formation Habshan (Berriasien/Valanginien), afin d'examiner les grandes différences verticales et latérales des propriétés pétrophysiques. Le MEB a été utilisé pour étudier deux contrôles potentiels des qualités réservoir : (1) la morphologie des particules micritiques (forme et contacts intercristallins), et (2) la cristallométrie des micrites, définie comme la taille médiane des particules mesurées sur les clichés MEB. Les données morphométriques ont été comparées avec trois paramètres pétrophysiques (porosité, perméabilité, distribution des rayons de seuil de pore). Les résultats montrent que les matrices micritiques peuvent être subdivisées en trois classes pétrophysiques. La Classe C (micrites strictement microporeuses avec des cristaux grossiers ayant des contacts punctiques à partiellement coalescents) est composée de particules grossières (>2µm), polyhédrales à arrondies. Elle présente des porosités bonnes à excellentes (8-28%), des perméabilités faibles à modérées (0,2-190mD), et des rayons de seuils de pores (PTR) moyens supérieurs à 0,5µm. Cette Classe C est généralement observée dans les shoals bioclastiques riches en rudistes, où de nombreux facteurs sédimentaires (hydrodynamisme…) peuvent défavoriser le dépôt des particules les plus fines. L'étude diagénétique montre que ces micrites grossières peuvent aussi être expliquées par une dissolution précoce des fines particules d'aragonite et de HMC dans des fluides météoriques oxydants, permettant la formation in-situ de surcroissances sur les particules de LMC au sommet de la nappe phréatique météorique. Ces processus induisent une augmentation de la taille des particules micritiques, une lithification précoce de la boue carbonatée, et donc une stabilisation minéralogique précoce des micrites grossières de la Classe C. La Classe F (micrites strictement microporeuses avec des cristaux fins ayant des contacts punctiques à partiellement coalescents, est composée de particules fines (<2µm), polyhédrales à arrondies. Elle présente des porosités bonnes à excellentes (3-35%), mais des valeurs de perméabilité souvent inférieures à 10mD, et des PTR inférieurs à 0,5µm. Cette Classe F est souvent observée dans les sédiments déposés en domaine de plate-forme interne boueuse. La formation de ces micrites fines est aussi expliquée par une stabilisation minéralogique précoce des particules micritiques dans des eaux météoriques confinées, favorisant les processus de néomorphisme, pouvant continuer au cours de l'enfouissement. Plus tard, au cours de l'enfouissement de la série, les qualités réservoirs des Classes C et F sont localement améliorées par de la dissolution mésogénétique (probablement liée à des acides organiques) affectant la matrice micritique durant la mise en charge des réservoirs. La Classe D est formée par des matrices micritiques denses, composées de cristaux anhédraux ou subhédraux avec des contacts fusionnés. Elle présente de très faibles données de porosité et de perméabilité. Ces micrites sont uniquement observées dans les niveaux de plate-forme interne et forment des intervalles inter-réservoirs, généralement en association avec des stylolites et un contenu argileux important, pouvant dépasser 10%. Quelque soit leur mode de formation, ces trois classes peuvent être incorporées dans les futures études de rock-typing portant sur les réservoirs carbonatés microporeux du Moyen-Orient / Microporosity may account for as much as 95% of the total porosity of hydrocarbon and water reservoirs in Cretaceous limestones of the Arabian Gulf. In these microporous facies porosity is moderate to excellent (up to 35%) while permeability is poor to moderate (up to 190mD). Conversely, microporous facies may form dense inter-reservoir or cap rock layers with very low porosity and permeability values (2–8% and 0.01–2mD, respectively). For this study, samples were mainly collected from the Cenomanian Mishrif Formation, but also from the Berriasian-Valanginian Habshan Formation, so as to examine the wide vertical and lateral discrepancies in their petrophysical parameters. Scanning Electron Microscopy was used to investigate two potential controls of reservoir properties: (1) micrite particle morphology (shape and inter-crystal contacts); and (2) micrite crystallometry, defined as the median size of micrite particles measured on SEM photomicrographs. The morphometric data are compared with three petrophysical parameters (porosity, permeability and pore threshold radius distribution). Results reveal that micrite matrixes can be subdivided into three petrophysical classes each with its own distinctive crystallometry, morphology and reservoir properties. Class C (strictly microporous limestones with coarse punctic-to-partially coalescent micrites) is made up of coarse (>2µm) polyhedral to rounded micritic crystals, it has good to excellent porosity (8–28%), poor to moderate permeability (0.2–190mD) and a mean pore threshold radius of more than 0.5µm. The class C is usually observed in rudist-rich bioclastic shoal facies where several sedimentary factors (hydrodynamism, bioproduction …) would disfavour deposition of the finer micritic crystals. Diagenetic study shows that the development of coarse micrites (Class C) must also be explained by the early dissolution of fine aragonite and high magnesium calcite particles in oxygenated meteoric fluids leading to a simultaneous in-situ overgrowth on LMC particles at the top of the meteoric phreatic lens. These processes induce an increase of the crystallometry of micritic particles, an early lithification of the carbonate mud, and so the mineralogical stabilization of coarse Class C micrites. Class F (strictly microporous limestones with fine punctic-to-partially coalescent micrites) is composed of fine (<2µm) polyhedral to rounded micrites with poor to excellent porosity (3–35%), but permeability values of less than 10mD and a mean pore threshold radius of less than 0.5µm. It is mostly observed in sediments deposited in a low energy muddy inner platform setting. The formation of fine micrites (Class F) is also explained by an early mineralogical stabilization of micritic particles in confined meteoric waters, favoring neomorphism processes, which may proceeds during burial. Later, during burial, reservoir properties of classes C and D strictly microporous samples where locally enhanced by mesogenetic dissolution (probably due to organic acids) affecting the microporous matrix during the oil emplacement. Class D (strictly microporous mud-dominated facies with compact anhedral to fused dense micrites) comprises subhedral to anhedral crystals with sutured to fused contacts forming a dense matrix. It has very low porosity and permeability. Class D is only found in low energy muddy inner platform facies and forms inter-reservoir or caps rock layers usually in association with stylolites and clay contents that exceed 10%. Regardless of how they formed, though, the three classes can be usefully incorporated into future rock-typing of the microporous carbonate reservoirs of the Middle East

A modified oil-in-water emulsion process was developed to produce novel microporous hemi-spherical polycaprolactone (PCL) microparticles called “hemi-shells”. Through the addition of a porogen such as sodium bicarbonate into the PCL-dichloromethane oil phase and emulsification in an acidic polyvinyl alcohol aqueous phase, microporous hemi-shells formed as dichloromethane evaporated. Carbon dioxide gas evolution from the porogen reaction with the acidic aqueous phase created particles with an externally microporous shell and a large internal cavity. The hemi-shells were characterized by various methods, including scanning electron microscopy and optical microscopy which were specifically used to quantify the hemi-shell yield. The final number-average particle yield of the optimised manufacturing method for particle manufacture in the 50-200 micron size range was 84%. The number-average hemi-shell yield in the same size range was 41%. These novel microparticles have potential applications in tissue engineering and drug delivery / Dissertation (MEng)--University of Pretoria, 2011. / Chemical Engineering / unrestricted

Theoretical investigation of microporous materials for adsorption and catalysis Microporous materials are defined by a presence of pores with diameter smaller than 2 nm. They comprise a large variety of materials from amorphous materials to very well defined crystalline materials like zeolites or metal organic frameworks. Microporous materials are industrially very important group of materials used for adsorption, gas capture, molecular sieving, or heterogeneous catalysis. Zeolites are by far the most important group of microporous materials due to their use as catalysts for the petroleum cracking. One of the main limitations of the zeolite use in catalysis is their limited pore size. This obstacle can be solved by use of hierarchical zeolites with a secondary mesopore network which allows overcoming the diffusion problems. The aims of this study can be divided into two parts. In the first part, the structures of two-dimensional and hierarchical zeolites were investigated theoretically to identify the structure of new materials and to obtain reliable models to study the hierarchical zeolites. In the second part, the catalytic properties of several microporous materials were modelled to explain their experimental activity. The results of this thesis were used to identify the structure of a large...

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Les calcaires sont des roches sensibles aux phénomènes physiques et chimiques qui peuvent les dissoudre, les cimenter ou les fracturer. Dans ce cas, les propriétés des calcaires vont évoluer en fonction de ces différents processus qui varient dans le temps et dans l’espace. Or les réservoirs carbonatés peuvent s’étendre sur plusieurs centaines de kilomètres. Afin d’exploiter ces réservoirs géologiques (ressources en eau, gaz ou pétrole), il est donc nécessaire de caractériser en 3 dimensions leurs propriétés (porosité, perméabilité) ainsi que les hétérogénéités géologiques ou tectoniques, qui peuvent modifier la géométrie du réservoir ou ses propriétés. L’acquisition de données locales (affleurements, forages), réparties sur la totalité du réservoir, pose la question de leurs représentativités projetées sur l’ensemble du volume de roche mais aussi de leurs distributions entre les points d’acquisitions qui sont espacés de plusieurs kilomètres. Cette thèse propose d’étudier les propriétés des calcaires Urgoniens (d’âge Barrémien supérieur – Aptien inférieur) situés en Provence, analogues aux calcaires des réservoirs d’hydrocarbures présents au Moyen-Orient. Trois sites comportant différentes échelles sont étudiés afin de caractériser cette série carbonatée. L’étude propose ensuite des règles géologiques dans le but d’extrapoler les mesures réalisées sur des échantillons d’unités centimétriques à l’échelle hectométrique / Carbonates are sensitive to physical and chemical processes which can dissolve, cement or fracturing them. In this case, the carbonate properties evolve according to these different changes that vary in time and space. Carbonated reservoirs can extend for hundreds of kilometres. To prospect these geological reservoirs (water, gas or oil resources), it’s therefore necessary to characterize in 3 dimensions their properties (porosity, permeability), as well as geological and structural heterogeneities which can modify the basin geometry or the reservoir properties. The acquisition of local data (outcrops, boreholes) compared to the properties distributed at field scale ponder their representativeness at multi-kilometres scale but also their distribution between the acquisition area. This thesis proposes to study the properties of Urgonian limestones (Upper Barremian - Lower Aptian) located in Provence, analogue of Middle East hydrocarbon reservoirs. Three sites with different scales are studied to characterize this carbonate series. Additionally, this study proposes geological rules to upscale the measurements made on centimetric samples to hectometric scale

京都大学 / 0048 / 新制・論文博士 / 博士(工学) / 乙第12846号 / 論工博第4103号 / 新制||工||1601(附属図書館) / 31429 / (主査)教授 北川 進, 教授 杉野目 道紀, 教授 松田 建児 / 学位規則第4条第2項該当 / Doctor of Philosophy (Engineering) / Kyoto University / DGAM

The battery separator is a component of the conventional battery that for long has been overlooked. Just because it’s the only inactive component, doesn’t mean it’s any less important for the battery cell. Recent trends point to an immense growth of the electrical vehicle-industry, and by so, also the lithium-ion battery separators market. This is because the lithium-ion battery is the most common battery type in commercial electrical vehicles. In one of the major manufacturing processes of the separator, mineral oil is used, to achieve a porous film. This study aims to evaluate different oils interaction with the polymer resin in the manufacturing process. Since most oils used in the battery separator industry today use paraffin rich oils, oils with different naphthenic content is tested to find correlations between the oils properties and the crystallinity or the porosity. No correlations for either the porosity or the crystallinity could be made to the oil’s properties. The images taken with the SEM was not enhanced enough to study the pores themselves or the pore structure of the films. For future studies it is recommended to collect more data to identify outliers so more accurate values are obtained. The methodology needs to be verified to ensure the procedure is reproducible. For the study of the pores and the pore structure, an FE-SEM should be used to achieve greater quality enhancement images on the surface of the films. / Batteri separatorn är en komponent i det konventionella batteriet som länge har förbisetts. Bara för att den är en inaktiv komponent, betyder inte att den är mindre viktig för battericellens prestation. Trender idag pekar mot en enorm tillväxt inom elbils-industrin, och med det även litium-jon batteriseparatorns marknad. Det är för att litium-jon batteriet är det batteriet som vanligen används kommersiellt idag i elbilar. I en av de två stora industriella tillverkningsprocesserna används olja för att åstadkomma en porös film. Denna studie syftar på att utvärdera olika oljors interaktion med polymeren i denna tillverkningsprocess. Eftersom de flesta batteriseparator-industrier idag använder paraffinrik olja så testas oljor med olika mycket naftalensikt innehåll för att hitta korrelationer mellan oljornas egenskaper och kristalliniteten eller porositeten hos filmerna. Inga korrelationer för porositeten eller kristalliniteten kunde göras till oljornas egenskaper. Bilderna tagna med SEM var ej tillräckligt förstorade för att kunna studera vare sig porstorleken eller porstrukturen hos filmerna. För framtida studier rekommenderas att samla in mer data för att kunna utskilja ”outliers” i datan, för att erhålla mer korrekta värden. Metodiken måste även verifieras för att säkerställa att proceduren är reproducerbar. För att studera porerna och porstrukturen, borde en FE-SEM användas för att få mer förstorade bilder med bättre kvalité på filmernas yta.

This research evaluated the influence of concentration and surface tension (γ) of aqueous solutions of a non-ionic surfactant on the barrier effectiveness of a fabric containing microporous polypropylene (PP) film that may be used in pesticide protective clothing (PPC). Aqueous solutions of Triton® X-100, a non-ionic surfactant, at various concentrations were prepared, and the γ of each solution was determined. The immediate advancing contact angles (θ), made by a 5-<i>μ</i>L drop of each test liquid on the test fabric, were measured. Barrier effectiveness was evaluated from the capillary penetration, wicking, and wetting characteristics of the fabric using the surfactant solutions at various concentrations. Wetting characteristics were evaluated from the drop absorbency test, a modified Draves test, the spreading coefficient (S_c) values and, by inference, from a Zisman plot. As surfactant concentration increased, γ decreased, and then remained relatively steady past the 0.0134 percent concentration level, the critical micelle concentration (CMC) of Triton® X-100. As Triton® X-100 concentration increased, θ decreased, even past the CMC. Results of the study indicate that, as surfactant concentration increases, the amount of capillary penetration and the wicking distance increase even past the CMC. The time for drop absorbency and the Draves wetting tests were very high (> 600 seconds) for all liquids below CMC. Beyond the CMC, drop absorbency times were significantly lower for solutions of 2.0 and 5.0 percent concentration, and the Draves wetting times were also significantly lower. The values of the cos θ and the γ were used to calculate the S_c for each liquid. The calculated spreading coefficients indicate that the liquids at all concentrations did not spread (wet) on the micro-porous PP test fabric for the advancing θ measured within 10 seconds of placing the drop. Results of the statistical analysis showed that surfactant concentration was a significant factor in determining the barrier effectiveness of the fabric tested. Even though γ remained relatively unchanged beyond the CMC of the surfactant, the inability of the test fabric to serve as an effective barrier against liquid penetration by capillary action, wicking, and wetting increased significantly. Surface energy terms, that are normally used to explain liquid transport and wetting phenomena, may not in themselves be sufficient to determine the effectiveness of a fabric for PPC, especially since concentration of the surfactant, a pesticide adjuvant, is a significant factor in determining the barrier effectiveness of PPC. Consideration must be made for the fact that very high concentrations of surfactants are routinely used in pesticide application. / Master of Science

The typical architecture of the proton exchange membrane fuel cell (PEMFC) contains a layer called the microporous sublayer (MSL). The MSL is a mixture of carbon black and polytetrafluoroethylene (PTFE), which is typically applied to the gas diffusion layer (GDL). The composition (wt.% PTFE) and loading (mg/cm2) can be varied to optimize the electrochemical performance of the PEMFC and the overall adhesion of the layers within the PEMFC. This research establishes correlations that characterize the performance and adhesion of the layers within the PEMFC based on composition, loading, fabrication pressure, and fabrication time. MSL loading was varied from 1.5-4 mg/cm2, composition was varied from 10-50 wt.% PTFE, fabrication pressure was varied from 3.45-10.34 MPa, and fabrication time was varied from 2-8 minutes. Using these four factors, correlations were created, and optimal solutions for each response were identified. The adhesion correlation identifies a low MSL loading, mid-range MSL composition, high fabrication pressure, and high fabrication time as desirable factors. The performance correlation suggests that the PEMFC performance is enhanced with low MSL loadings, low MSL PTFE content, and a low fabrication pressure and does not find fabrication time to be a significant factor in the correlation. / Master of Science

The three-stage (extrusion, annealing, stretching) method of producing microporous membranes from linear polyethylene (HDPE) was investigated in this dissertation. Two different HDPE resins with identical M̅_n (14,600) values but different distributions (M̅_w/M̅_n=10.3, 15.1) were utilized for this study. In the extrusion process, the two HDPE resins were melt extruded into uniaxially oriented tubular films. Systematical changes were made in the process variables -- these being the melt temperature at the die exit, the quench height, the cooling rate, and the line speed. The melt relaxation time behavior of the HDPE resins was studied by a Carreau-Yasuda analysis. The orientation morphological features of the extruded films were examined by TEM, HSEM, birefringence, WAXS, SAXS, and linear IR dichroism. The molecular weight distribution of the raw resins as well as the specific processing variables of quench height and melt temperature were found to be important in determining the final structure of the HDPE extruded films. Following the extrusion process, the effect of annealing on the structure and properties of the HDPE extruded films was investigated. The HDPE extruded films were annealed under different conditions. The annealing variables studied included the temperature, the line speed (or annealing time), and the amount of extension applied during annealing. The extruded films before and after annealing were characterized by DSC, WAXS, SAXS, birefringence, and TEM. The results suggest that upon annealing, perfection of the crystalline phase occurs by removal of the defects from the crystalline phase. In the last step, the precursors (either the extruded films or the extruded films after being annealed) were uniaxially deformed along the extrusion direction. The variables of cold stretch ratio, hot stretch ratio, and total stretch percent were varied to alter the properties of the stretched microporous membranes. The pore structure, porosity, and permeability of the stretched microporous films were analyzed by TEM, HSEM, AFM, DSC, and Gurley number measurements. The importance of the orientation and morphological properties of the precursors, the annealing effects of the HDPE extruded films, and the stretching variables for influencing the microporosity behavior of the HDPE microporous membranes is clearly made evident in this dissertation. / Ph. D.