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Im Dynamoprozess werden Magnetfelder zahlreicher astrophysikalischer Objekte durch die Strömung elektrisch leitfähiger Fluide verstärkt. Das Von Kármán Sodium Experiment, in dem zwei Impeller aus Weicheisen flüssiges Natrium antreiben, dient zur Untersuchung dieses Prozesses. Fragen zur Wechselwirkung der flüssigen und festen Komponenten bleiben jedoch offen. Im Rahmen dieser Arbeit wurde ein Pseudospektral-Verfahren zur Lösung der MHD-Gleichungen mit einer Penalty-Methode zur Modellierung der Impeller kombiniert, um direkte numerische Simulationen dieses Systems durchzuführen. Dies erlaubt Analysen der Geschwindigkeits- und Magnetfeldstrukturen jenseits experimenteller Möglichkeiten. Eine Annäherung an die experimentellen Materialkonstanten führt zu einer Verstärkung des Dynamos und zur Ausprägung der im Experiment beobachteten axialsymmetrischen Magnetfeldgeometrie. Die Simulationen geben zudem Aufschluss über den zugrundeliegenden Mechanismus., In the dynamo process, magnetic fields of numerous astrophysical objects are amplified by the flow of electrically conducting fluids. The Von Kármán Sodium Experiment, in which two soft-iron impellers drive liquid sodium, serves the investigation of this process. Questions concerning the interaction of liquid and solid components, though, remain open. In the frame of this work a pseudo-spectral technique for the solution of the MHD equations is combined with a penalty method for the modelling of the impellers, in order to perform direct numerical simulations of this system. This allows for the analysis of velocity and magnetic field structures beyond experimental capabilities. An approximation towards the experimental material constants leads to an enhancement of the dynamo and to the manifestation of the experimentally observed axisymmetric magnetic field geometry. The simulations also shed light on the underlying mechanism.

Peer reviewed: True, Funder: Project PID2020–115374GB-100, Funder: Erasmus-Mundus Action-2 program, Avempace II project, from the European Union, The application of a computational screening methodology based on the calculation of intermolecular interaction energies has guided the discovery of new multicomponent solid forms of the oral antiviral Adefovir Dipivoxyl. Three new cocrystals with resorcinol, orcinol and hydroquinone have been synthesized and thoroughly characterized. They show improved dissolution profiles with respect to the single solid form, particularly the cocrystals of orcinol and resorcinol, which have 3.2- and 2-fold faster dissolution rates at stomach conditions (pH 1.5). Moreover, dynamic dissolution experiments that simultaneously mimic both the pH variation along the gastrointestinal tract and the partition into biological membranes show that, in addition to the faster initial dissolution, Adefovir Dipivoxyl also penetrates faster into the organic membranes in the form of resorcinol and orcinol cocrystals.

El projecte queda emmarcat en la reinterpretació productiva de l'àrea Olímpica de la Vall d'Hebron. Es realitza una investigació sobre l'espai lliure de la ciutat. Reflexionem sobre els elements que actualment estan infravalorats per, amb les mínimes actuacions necessàries, fer-los valdre en relació amb les funcions que prenen cap als usuaris de la ciutat. S'entén que la intocabilitat de certs espais, promoguda per un sentimentalisme i nostàlgia, ens impedeix entendre que els llocs necessiten continuar transformant-se per no caure en un conservadorisme que pot mantenir la imatge urbana però no la identitat de la ciutat. S'investiga sobre com potenciar la reconquesta natural de l'espai públic, augmentar la permeabilitat per generar les condicions propícies al desenvolupament de la diversitat biològica. El verd també es tracta d'una eina que permet generar dinàmiques socials de comunitat i de cohesió, permetent als usuaris empoderar-se i tenir la iniciativa de prendre decisions sobre l'espai que estan habitant. El projecte estudia modificar el règim de gestió de les aigües pluvials d'escorrentiu a les ciutats. Es vol promoure una mentalitat contemporània basant-se a impulsar sistemes ambientals que permetin aprofitar l'aigua reintroduint-la al subsol i permetre, recarregant els aqüífers, tancar el cicle natural de l'aigua. El proyecto queda enmarcado en la reinterpretación productiva del área Olímpica del Vall d'Hebron. Se realiza una investigación sobre el espacio libre de la ciudad. Reflexionamos sobre los elementos que actualmente están infravalorados para, con las mínimas actuaciones necesarias, hacerlos valer en relación con las funciones que toman hacia los usuarios de la ciudad. Se entiende que la intocabilidad de ciertos espacios, promovida por un sentimentalismo y nostalgia, nos impide entender que los lugares necesitan seguir transformándose para no caer en un conservadurismo que puede mantener la imagen urbana pero no la identidad de la ciudad. Se investiga sobre cómo potenciar la reconquista natural del espacio público, aumentar la permeabilidad para generar las condiciones propicias al desarrollo de la diversidad biológica. El verde también se trata de una herramienta que permite generar dinámicas sociales de comunidad y de cohesión, permitiendo a los usuarios empoderarse y tener la iniciativa de tomar decisiones sobre el espacio que están habitando. El proyecto estudia modificar el régimen de gestión de las aguas pluviales de escorrentía en las ciudades. Se quiere promover una mentalidad contemporánea basándose en impulsar sistemas ambientales que permitan aprovechar el agua, reintroduciéndola en el subsuelo y permitir, recargando los acuíferos, cerrar el ciclo natural del agua. The project is part of the productive reinterpretation of the Olympic area of the Vall d’Hebron. An investigation is carried out on the free space of the city. We reflect on the elements that are currently undervalued in order, with the minimum necessary actions, to make them valid in relation to the functions they take on for the users of the city. It is understood that the untouchability of certain spaces, promoted by sentimentality and nostalgia, prevents us from understanding that places need to continue transforming in order not to fall into a conservatism that can maintain the urban image but not the city's identity. Research has been done on how to enhance the natural reconquest of public space, increase permeability to generate the conditions to the development of biological diversity. Green is also a tool that generates social dynamics of community and cohesion, allowing users to empower themselves and take the initiative to make decisions about the space they inhabit. The project studies modifying the rainwater runoff management regime in cities. The aim is to promote a contemporary mentality based on promoting environmental systems that make it possible to take advantage of water by reintroducing it into the subsoil and allow, by recharging the aquifers, to close the natural water cycle. Award-winning

This paper jointly addresses numerical and physical challenges related to the modeling of coalescence filtration through vertical filter cartridges, put forth in the following papers by Starnoni, M. and C. Manes: • Starnoni, M., & Manes, C. (2021). A multiphase multicomponent flow and transport model for liquid aerosol filtration in coalescence fibrous filters. Separation and Purification Technology, 266, 118574. • Starnoni, M., & Manes, C. (2022). On the interplay between pressure and gravitational forces in coalescence filters. Journal of Aerosol Science, 105953. In particular, it provides the multidimensional extension of the one-dimensional model presented in Starnoni and Manes (2021) to the general case where internal gravity-induced flows play an effective role. Key to the implementation is the decomposition of the moving oil volumes along the different directions proportionally to the dimensionless number SM, a new quantity introduced in Starnoni and Manes (2022) describing the interplay between the forces dictating the oil dynamics. To validate the implementation, an experimental setup available in the literature is replicated, showing very good agreement in terms of all relevant quantities, namely saturation, pressure drop and drainage volumes. A generalized ‘Network, Channel and Film’ model is also formulated, which extends the scope of application of the original Jump and Channel model by Kampa et al. (2014) to filters with coarser fibrous microstructure. In particular, the existence of an additional flow mechanism termed ‘network’ is postulated, which is characterized by a complex multidimensional oil patterns configuration spanning the entire filter’s height and evolving, in a macroscopic sense, along the direction identified by SM.

In dieser Arbeit wird meine Forschung an verschiedenen natürlichen Kluftnetzsysteme in Karbonatgesteinen dokumentiert. Kluftnetzwerke in Karbonaten werden anhand von Datensätzen (Feldbeobachtungen, Drohnenaufnahmen, photogrammetrisch verarbeiteten Bildern und Google-Satellitenbildern) interpretiert. Auswirkungen von Änderungen des Spannungsregimes auf die Permeabilität von Kluftnetzwerken werden mithilfe eines neuartigen Arbeitsablaufs und einer neuen Strategie quantifiziert. Die Öffnungsverteilung wird mittels einer verschiebungsbasierten linear-elastischen Finite-Elemente-Methode (FEM) in einem mechanischen 2-D-Modell bestimmt. Das Verfahren umfasst die Modellierung von zwei realistischen Druck-Randbelastungen (Fernfeldspannungen analog zu \(\textit {in situ}\) Spannungen) und der lokalen Zustandsspannung, um die Auswirkungen der Spannung auf die Permeabilität zu beschreiben. Dadurch können natürliche Kluftnetzwerke an Aufschlüssen und in unterirdischen Lagerstätten besser charakterisiert werden.

We investigated the diffusion of three cyclic boronates formulated as beta-lactamase inhibitors through the porin OmpF to evaluate their potential to cross OM via the porin pathway. The three nonbeta-lactam molecules diffuse through the porin eyelet region with the same mechanism observed for beta-lactam molecules and diazobicyclooctan derivatives, with the electric dipole moment aligned with the transversal electric field. In particular, the BOH group can interact with both the basic ladder and the acidic loop L3, which is characteristic of the size-constricted region of this class of porins. On one hand, we confirm that the transport of small molecules through enterobacter porins has a common general mechanism; on the other, the class of cyclic boronate molecules does not seem to have particular difficulties in diffusing through enterobacter porins, thus representing a good scaffold for new anti-infectives targeting Gram-negative bacteria research.

Die Laborexperimente in dieser Arbeit wurden konzipiert und durchgef��hrt, um die Permeabilit��t und die spezifische Speicherkapazit��t und deren zeitliche Entwicklung von intakten und gebrochenen Gesteinen in Abh��ngigkeit von Druck, Temperatur und Rauheit zu untersuchen. Diese Experimente liefern wichtige Eingangsdaten und entscheidende Randbedingungen f��r Betriebsprozesse f��r die Modellierung des fr��hen Betriebs eines geothermischen Reservoirs, wenn S����wasser injiziert wird und Risse erzeugt (Stimulation), aber auch f��r den langfristigen Betrieb. Wir haben uns f��r eine Gesteinskombination entschieden, die nicht nur den Oberrheingraben modelliert, sondern auch in Zusammensetzung (siliziklastisches, karbonatisches bis kristallines Gestein) und Mikrostruktur (K��rnchen, Mikrorisse, Verkarstung) ein betr��chtliches Spektrum an Lithologien repr��sentiert. Bei konstanter Temperatur, wenn der Begrenzungsdruck ansteigt, nehmen die hydraulische Bruch��ffnung und die Permeabilit��t schnell ab.

Detaillierts Wissen über die Eigenschaften von Gesteinen spielt bei einer Vielzahl technischen Anwendungen, wie etwa der Geothermie oder der Erdölförderung eine zentrale Rolle. Häufig sind diese Eigenschaften nicht nur von der Zusammensetzung der Gesteine, sondern auch vom jeweils herrschenden Druck abhängig. Zur Vorhersage dieser Größen können experimentelle Methoden verwendet werden. Eine Alternative stellt die Simulation dar. In der vorliegenden Arbeit werden zwei neue Simulationsmodelle zur Bestimmung von druckabhängigen Gesteinseigenschaften entwickelt und validiert. Im Speziellen werden die Wärmeleitfähigkeit und Permeabilität als Zielgrößen definiert. Beide Ansätze basieren dabei auf den Methoden der digitalen Gesteinsphysik. Ausgehend von einer hochaufgelösten CT-Aufnahme wird ein numerisches Modell der zu untersuchenden Gesteinsstruktur erstellt. Auf Basis dieses Modells werden die Simulationen durchgeführt., Detailed knowledge about the properties of rocks plays a central role in a variety of technical applications, such as geothermal energy or oil production. Often, these properties depend not only on the composition of the rocks, but also on the confining pressure. Experimental methods can be used to predict these properties. As an alternative, simulations can be carried out. In the present work, two new simulation models for the determination of pressure-dependent rock properties are developed and validated. In particular, thermal conductivity and permeability are defined as the target properties. Both approaches utilize the methods of digital rock physics. Starting from a high-resolution CT image, a numerical model of the rock structure is created. Based on this model, the simulations are carried out.

En aquest treball s'estudia la permeabilitat i els límits de la línia de Renfe R1, en el tram de la costa entre els municipis de Sant Adrià del Besòs i Malgrat de mar.

Los depósitos de relaves presentan características geotécnicas que los hacen susceptibles de sufrir falla por licuefacción, por lo que las implicaciones de riesgo de este rasgo sólo se han apreciado en su totalidad recientemente. Por ello, es de interés actual estudiar las posibles técnicas de remediación de los depósitos existentes, centrándose en las posibilidades de tratamiento de los relaves mediante inyecciones por permeación. La tesis comienza presentando una visión general de los métodos de manejo de residuos y de las propiedades geotécnicas de los depósitos. Además, se presta especial atención a la permeabilidad mediante la ecuación propuesta por Chapuis y Aubertin (2003) y evaluada a partir de una base de datos de propiedades de relaves proporcionada por el Instituto Geológico y Minero de España. En consecuencia, se recalibra la ecuación original y se verifica utilizando los valores de permeabilidad de otros estudios publicados. A continuación, se revisan los posibles métodos de tratamiento del terreno adaptados a los relaves, divididos en tres grandes categorías: densificación, consolidación y tratamientos químicos. A continuación, se determina que el método de inyección por permeación es el más adecuado. A través de la evaluación de dos productos de sílice coloidal MP320 y MP325, aplicadas a un caso basado en la presa de Merriespruit, se obtienen los resultados de factor de seguridad, tiempos de ejecución y costo total de operación. A partir de los resultados obtenidos, se puede abrir la puerta a futuros estudios aplicados a la remediación de depósitos de relaves mediante tratamiento de inyección por permeación Tailing deposits present geotechnical characteristics which make them susceptible to liquefaction flow failure, hence the risk implications of this trait have only been recently appreciated in full. It is therefore of current interest to study possible remediation techniques for existing deposits. This dissertation contributes to this end by focusing on the possibilities of tailing treatment by permeation of cementing agents. The thesis starts by presenting an overview of tailing disposal methods and geotechnical properties of tailing deposits. Furthermore, special attention is paid to permeability by examining the equations proposed by Chapuis and Aubertin (2003) and evaluated using a database of tailings properties provided by the Geology and Mine Institute of Spain. Consequently, the original equation is recalibrated and then verified using permeability values from other published studies. Possible ground treatment methods for tailings are then reviewed in three broad categories: densification, consolidation, and chemical treatments. It is then determined that permeation grouting method is the best adapted. Pre-design and evaluation of ground improvement treatment for a tailing dam are then carried on for two colloidal silica products (MP320 and MP325) in a case comparable to the Merriespruit tailing dam, which failed by overtopping-induced liquefaction. Through the evaluation of two colloidal silica products MP320 and MP325, applied to a case based on the Merriespruit dam, the safety factor results are then obtained and so the time and cost of operation. From these obtained results, a new door can be opened to future studies applied to the remediation of tailings deposits by permeation injection treatments. Els dipòsits de relaves presenten característiques geotècniques que els fan susceptibles de patir falla per liqüefacció, de manera que les implicacions de risc d'aquest tret només s'han apreciat en la seva totalitat recentment. Per això, és d'interès actual estudiar les possibles tècniques de remediació dels dipòsits existents, centrant-se en les possibilitats de tractament dels relaves mitjançant injeccions per permeació. La tesi comença presentant una visió general dels mètodes de maneig de residus i de les propietats geotècniques dels dipòsits. A més, es presta especial atenció a la permeabilitat mitjançant l'equació proposada per Chapuis i Aubertin (2003) i avaluada a partir d'una base de dades de propietats de relaves proporcionada per l'Institut Geològic i Miner d'Espanya. En conseqüència, es recalibra l'equació original i es verifica utilitzant els valors de permeabilitat d'altres estudis publicats. A continuació, es revisen els possibles mètodes de tractament del terreny adaptats als relaves, dividits en tres grans categories: densificació, consolidació i tractaments químics. A continuació, es determina que el mètode d'injecció per permeació és el més adequat. A través de l'avaluació de dos productes de sílice col·loïdal MP320 i MP325, aplicades a un cas basat en la presa de Merriespruit, s'obtenen els resultats de factor de seguretat, temps d'execució i cost total d'operació. A partir dels resultats obtinguts, es pot obrir la porta a futurs estudis aplicats a la remediació de dipòsits de relaves mitjançant tractament d'injecció per permeació.

In traditional architecture, the construction systems used have always been linked to the material resources of the environment. In the areas of extraction of gypsum in the Iberian Peninsula, the use of this material as a conglomerant was not limited to the interior lining of vertical and/or horizontal walls or to interior decorations, as is the case today, but proved to be a very versatile material, which could be used both in structural elements and in finishing elements and decorations. This study shows the preliminary results of an ongoing research on the recovery of traditional gypsum pavements, where three types of traditional gypsum plasters with natural products such as collagen, coconut soap, potassium soap, vegetable oil and marshmallow root were tested. The hygroscopic behaviour of the treated samples has been evaluated from the capillarity water absorption and the contact angle, due to their high hygroscopicity. On the other hand, the density and porosity, surface hardness and thermal conductivity of the samples have also been determined. Award-winning

Oleacein (OLEA) is one of the most important phenolic compounds in extra virgin olive oil in terms of concentration and health-promoting properties, yet there are insufficient data on its absorption and metabolism. Several non-human models have been developed to assess the intestinal permeability of drugs, among them, single-pass intestinal perfusion (SPIP), which is commonly used to investigate the trans-membrane transport of drugs in situ. In this study, the SPIP model and simultaneous luminal blood sampling were used to study the absorption and metabolism of OLEA in rats. Samples of intestinal fluid and mesenteric blood were taken at different times and the ileum segment was excised at the end of the experiment for analysis by LC–ESI–LTQ–Orbitrap–MS. OLEA was mostly metabolized by phase I reactions, undergoing hydrolysis and oxidation, and metabolite levels were much higher in the plasma than in the lumen. The large number of metabolites identified and their relatively high abundance indicates an important intestinal first-pass effect during absorption. According to the results, OLEA is well absorbed in the intestine, with an intestinal permeability similar to that of the highly permeable model compound naproxen. No significant differences were found in the percentage of absorbed OLEA and naproxen (48.98 ± 12.27% and 43.96 ± 7.58%, respectively).

Treballs Finals de Grau de Química, Facultat de Química, Universitat de Barcelona, Any: 2021, Tutors: Fermín Huarte Larrañaga, Pablo Gamallo Belmonte, Carbon-based membranes are a novel approach to gas separation. More precisely, new graphene-like structures are of utmost importance in this field of research. The scope of this work is to prove the effectiveness of grazyne membranes in the separation of different gaseous mixtures: carbon dioxide (CO2) with methane (CH4) and CO2 with oxygen (O2). To determine the efficiency of the membrane, a molecular dynamics simulation is carried via Large-scale Atomic/Molecular Massively Parallel Simulator (LAMMPS) undergoing an adaptive intermolecular reactive bond order (AIREBO) force field. Grazynes are a recently proposed family of 2D carbon allotropes consisting in graphene-like stripes bonded via acetylenic links, which allow for the design of pores of variable size, an important property for gas separation. For these simulations, the studied membrane was [1],[2]{2}-grazyne. The focus of the research was to determine their permeability and selectivity for both mixtures at different sets of pressures and constant temperature. To achieve this, a box was simulated in which a piston-like wall was set at different heights. Due to computational restraints, simulations at low pressure values (i.e. lower than 10 atm) were performed with c(2x2) supercells. The results were conclusive in determining the [1],[2]{2}-grazyne membrane as infinitely selective for CO2 over CH4 between 1 and 20 atm, meaning the membrane was impermeable for methane. For the CO2/O2 mixture, further simulations were performed with [1],[3]- and [1],[m]{1}-grazynes (m=1,2,3) as no selective separation could be carried out. No conclusive data could be obtained from such simulations, as the only selective separations occurred when only a single molecule was filtered.

Dissertation, Rheinisch-Westfälische Technische Hochschule Aachen, 2021; Aachen : RWTH Aachen University 1 Online-Ressource : Illustrationen, Diagramme (2021). = Dissertation, Rheinisch-Westfälische Technische Hochschule Aachen, 2021, Within the last decades, there has been an increasing amount of scientific studies on transport and storage mechanisms in tight rocks due to the growing interest in geotechnical applications, such as nuclear waste disposal, storage of carbon dioxide or enhanced oil/gas recovery. Gas flow and uptake experiments in tight rocks are commonly controlled by complex interactions of multiple rock- and fluid-specific properties, giving rise to transport- and storage-specific phenomena, such as fluid-dynamics (e.g. slip flow), poro-elasticity (e.g. pore compressibility) and sorption. These phenomena are superimposed and omnipresent in geologic formations and, therefore, significantly complicate the investigation and isolation of effects on a laboratory basis. In order to perform experiments at near-realistic subsurface conditions, a vast range of pore and confining pressures is required. For this thesis, single-phase gas permeability and uptake experiments were performed on (1) synthetic porous media (ceramic disk, capillary tubes), (2) the Triassic Grey Weser Sandstone and (3) ten Permian black shale samples from the Karoo Supergroup (South-Africa). The datasets were complemented by a wide range of supplementary petrophysical and geochemical measurements. Chapter 2 focuses solely on fluid-dynamic effects of different gases on synthetic porous media. Pore characterization of the nanoporous ceramic disk was performed by different methods that essentially showed similar results for porosity (~ 28%) and most prominent pore diameter (~ 68.5 nm). Flow experiments with the ceramic (>99% Al2O3), per-formed at confining pressures from 10 to 50 MPa, did not show any stress-dependence of the permeability. Second-order slip flow effects could not be observed as the apparent gas permeability coefficients show linear Klinkenberg trends over a gas pressure range from 0.2 to 30.5 MPa. In comparison with all other gases used, the Klinkenberg-corrected (or intrinsic) permeability coefficients measured with helium were consistently higher. Compared to tight rocks, this “helium anomaly” is significantly less pronounced and likely linked to complex gas-solid interactions (e.g. sorption). Further, permeability measurements with carbon dioxide showed deviations from the linear Klinkenberg trend in close proximity to its critical pressure (7.38 MPa). The non-linearity is caused by substantial changes in thermodynamic properties of supercritical CO2 (e.g. density, compressibility, viscosity). Chapter 3 deals with a combination of fluid-dynamic (slip flow) and poro-elastic (pore and bulk compressibility) effects studied on the Grey Weser Sandstone. Gas permeability experiments were coupled with volumetric strain measurements at pore and confining pressures up to 30 and 50 MPa, respectively. Permeability and strain results could only be described by the modified effective stress laws for apparent permeability (χ = 1.25) and volumetric strain (Biot α = 0.7), respectively. To predict apparent permeability at any combination of given pore and confining pressure, an apparent permeability model has been applied on the measured permeability data. Ultimately, combined permeability and strain results were described by means of a “clay-shell” pore model. In chapter 4, ten Karoo black shales from the Collingham, Whitehill and Prince Albert Formation were investigated with respect to their gas generation potential, transport properties and storage capacity. Total organic carbon (TOC) contents range from 0.5 to 6.1 wt.% and are clearly highest for the Whitehill Formation. All samples are highly overmature and peak gas generation probably occurred due to tectono-metamorphic overprinting. Throughout all samples, porosity and permeability range from 4.1% to 6.3% and 1 to 100 nDarcy, respectively. Neither porosity nor permeability show significant stress-dependence. Sorption capacity is highest for the TOC-rich Whitehill Formation. Accordingly, gas storage capacity of the Whitehill Formation was estimated at unstressed and stressed conditions. Based on porosity and permeability results, a one-dimensional pressure diffusion model was applied to estimate the theoretical time required for 100% reservoir depletion. The findings presented in this study contribute to an improved understanding of fluid flow and stress phenomena in tight rocks, and can make contributions for improved evaluation and interpretation of gas permeability data and fluid flow modelling at reservoir and pore scales., Published by RWTH Aachen University, Aachen

Recently, in February 2020, we published a study exploring the intestinal absorption and metabolism of oleocanthal (OLC) in rats. A single-pass intestinal perfusion technique (SPIP) was used, involving simultaneous sampling from the luminal perfusate and mesenteric blood. Later, comments on our published paper were released, requesting clarification of specific data. In this detailed reply, we hope to have addressed and clarified all the concerns of A. Kaddoumi and K. El Sayed and that the scientific community will benefit from both the study and the comments it has generated. ispartof: PHARMACEUTICS vol:12 issue:12 ispartof: location:Switzerland status: published

The primary purpose of this thesis is to find out the mechanism of cracking formation during filtration as well as improve the dewatering efficiency of Limestone and Vietnam coal. They are both fine materials, which negatively affect the filtration process. Experiments are executed by changing parameters like solid volume fraction of initial suspension, the height of filter cake and the applied pressure difference using the conventional pressure filtration. Permeability ratio is used as the relevance output parameter to quantify the degree of cracking. Otherwise, saturation and residual moisture content on filter cake are also calculated to evaluate the extent of dewatering. Almost the mechanism of cracking is assumpted and proved. Countermeasures are suggested to prevent the probability and degree of cracking on filter cake. Otherwise, steam pressure filtration is applied as a new method allow improve the dewatering efficiency and reduce the cracking.:Contents Abstract iii Acknowledgment v Contents vi List of Figure viii List of Tables xvi List of Symbols xvii Abbreviation xix 1. Background 1 1.1. The Filtration process 1 1.2. Conventional pressure filtration and steam pressure filtration 3 1.3. Filtration theory 6 1.4. Cake deliquoring - immiscible fluid displacement in porous media 16 1.5. Tensile stress between particles 20 1.6. Coal processing/ washing 24 2. Literature review 34 2.1. Cracking on filter cake and the dewatering process with and without cracking 34 2.2. Summary and focus of research 47 3. Material, methods and the result of capillary pressure curve and tensile stress versus saturation 51 3.1. Material used 51 3.1.1. Limestone 51 3.1.2. Vietnam Coal 52 3.2. Conventional filtration rig and steam pressure filtration rig 55 3.2.1. Conventional filtration rig 55 3.2.2. Steam pressure filtration rig 57 3.3. Filtration experimental 58 3.4. Relevant parameter 59 3.5. Analyze technique 65 3.6. Tensile stresses depend on saturation during deliquoring 66 4. The influence of operating parameters on cracks formation in case of limestone 69 4.1. Capillary pressure curve and tensile stress during the filtration in the case of limestone 69 4.2. Test were conducted using conventional pressure filtration 76 4.2.1. Particle size distribution effect 76 4.2.2. The solid volume fraction of suspension effect 82 4.2.3. Height of filter cake (filter cake deep/ filter cake thickness) effect 92 4.2.4. Pressure difference effect 101 4.3. The difference in the crack formation by using steam pressure filtration 111 4.4. General conclusion 116 5. The influence of operating parameters on cracks formation in the case of Vietnam coal 118 5.1. Capillary pressure curve and tensile stress during filtration in case of Vietnam coal 118 5.2. Test were conducted using conventional pressure filtration 122 5.2.1. The influence of the solid volume fraction on crack formation and saturation 122 5.2.2. The influence of the height of filter cake on crack formation and saturation 127 5.2.3. The influence of pressure difference on crack formation and saturation 134 5.3. Estimate the efficiency dewatering as well as the crack formation using steam pressure filtration 139 5.4. General conclusion 146 6. Overall conclusion and recommendation 148 6.1. Overall conclusion 148 6.2. Recommendation 150 References 152 Appendices 156 Appendix A: Data from CCWP. 156 Appendix B: Data from the crack formation with various operation parameters using conventional pressure filtration (CPF). 159 Appendix C: Data from steam pressure filtration. 167 Appendix D: Miscellaneous Information. 177

In dieser Arbeit werden verschiedene Verfahren vorgestellt, um Saturnpartikel herzustellen. Es wird die Selbstanordnung von erfolgreich hergestellten Saturnpartikeln untersucht. Im ersten Teil werden durch ein äquatoriales Ätzverfahren Saturnpartikel mit hydrophoben Kappen sowie einem hydrophilen Gürtel aus hydrophob beschichteten sphärischen Partikeln hergestellt. Mit einer Monolage dieser Saturnpartikel können Membranen aus Wasser (sogenannte Pickering-Membranen) stabilisiert werden. Die Pickering-Membranen sind über einen Zeitraum von mehreren Tagen stabil und lassen Permeabilitätsuntersuchungen zu. Diese Pickering-Membranen können als ein Spezialfall einer Supported Liquid Membrane angesehen werden. Es werden die Permeabilitätsunterschiede von Kohlenstoffdioxid gegen Luft sowie Luft gegen Schwefelhexafluorid betrachtet. Die resultierenden Werte stimmen in zufriedenstellender Weise mit theoretisch – nach dem für Supported Liquid Membranes gängigen Löslichkeits-Diffusionsmodell – berechneten Werten überein. Im zweiten Teil werden Partikel über Float-casting in Membranen eingebettet und dadurch rundherum – nicht jedoch an den Polkappen – äquatorial maskiert. Anschließend wird Gold aufgedampft und die maskierende Membran entfernt, sodass Saturnpartikel zurück bleiben. Die Saturnpartikel weisen hydrophile Kappen sowie einen hydrophoben Gürtel auf. An einer Öl-Wasser-Grenzfläche kommt es zu einer Selbstanordnung dieser Saturnpartikel durch Verknüpfung ihrer Gürtel in Form von zweidimensionalen Netzwerken. In diesen Netzwerken können einfache geometrische Formen gefunden werden. Es ist dabei nicht möglich, die Partikel durch einen Krafteintrag in einem flächendeckenden Muster zu organisieren. Die Untersuchung erfolgt durch konfokale Fluoreszenzspektroskopie. Die Goldkappen der Saturnpartikel zeigen ein Fluoreszenzsignal.:Bibliographische Beschreibung und Referat Danksagung Inhaltsverzeichnis Abkürzungsverzeichnis 1 Einleitung 2 Theoretischer Teil 2.1 Januspartikel 2.1.1 Herstellungsmöglichkeiten 2.1.1.1 Herstellung durch Oberflächenmodifizierung 2.1.1.2 Phasenseparation zweier nicht mischbarer Flüssigkeiten 2.1.1.3 Herstellung aus Bausteinen über Selbstanordnung 2.1.2 Anwendung 2.2 Saturnpartikel 2.2.1 Herstellung durch Oberflächenmodifizierung 2.2.2 Herstellung durch Phasenseparation von nicht mischbaren Flüssigkeiten 2.2.3 Herstellung aus Bausteinen über Selbstanordnung 2.3 Partikelstabilisierte Membranen 2.4 Aktuelle Fortschritte in der Gastrennung Mittels Gestützter Flüssigmembranen 2.4.1 Gestützte Flüssigmembranen (Supported Liquid Membranes) 2.4.2 Flüssigkeiten 2.4.2.1 Nicht-Ionische Flüssigkeiten 2.4.2.2 Ionische Flüssigkeiten 2.4.2.3 Stark Eutektische Lösemittel 2.4.3 Matrixmaterialien 2.4.4 Träger 2.4.5 Trennaufgaben 2.4.5.1 CO2/N2 2.4.5.2 CO2/CH4 2.4.5.3 Alken/Alkan 2.4.5.4 Andere Trennaufgaben 2.4.6 Einfluss von Temperatur und Druck 2.4.7 Stabilität 2.4.8 Simulationen 2.4.9 Zusammenfassung und Ausblick des Kapitels 2.5 Grenzflächen 2.5.1 Grenzflächenspannung 2.5.2 Kontaktwinkel und Benetzung 2.5.3 Partikelassistierte Benetzung 2.5.3.1 Float-casting 2.6 Modifizierung von Oberflächen durch Selbstorganisierende Monoschichten 2.6.1 Silanisierung von Oberflächen 2.6.2 Thiolisierung von Oberflächen 2.7 Fluoreszenz 2.8 Netzwerkanalyse 3 Ergebnisse und Diskussion 3.1 Herstellung von Saturnpartikeln durch schrittweises Einsinken in ein Polymer 3.2 Herstellung von Saturnpartikeln mit geätztem Ring mit Ätzzelle 3.2.1 Beschreibung der Ätzzelle 3.2.2 Optimierung des Verfahrens 3.2.2.1 Einlegen der Thermoplastischen Folien in Ethanol 3.2.2.2 Einführung eines Luer-Lock-Systems 3.2.2.3 Erhöhung der Pumpgeschwindigkeit bei der Reinigung 3.2.3 Beschreibung der erhaltenen Saturnpartikel 3.3 Pickering-Membranen stabilisiert durch Saturnpartikel mit geätztem Ring 3.3.1 Permeabilitätsuntersuchungen von Pickering-Membranen 3.3.1.1 Theoretische Permeanzen 3.3.1.2 Experimentelle Permeanzen 3.4 Herstellung von Saturnpartikeln durch Beschichtung mit Gold und graduelles Ätzen 3.5 Herstellung von Saturnpartikeln über Float-casting 3.5.1 Herstellung von Saturnpartikeln über Float-casting: Glaspartikel 3.5.2 Herstellung von Saturnpartikeln über Float-casting: Siliziumdioxidpartikel 3.5.3 Herstellung von Saturnpartikeln über Float-casting: Silsesquioxanpartikel 3.5.3.1 Bestimmung der Schichtdicke des Goldes 3.5.3.2 Membranherstellung mit Silsesquioxanpartikel über Floatcasting 3.5.3.3 Oberflächenmodifizierung der Goldkappen 3.6 Selbstanordnung von Saturnpartikeln unter dem Konfokalmikroskop 3.6.1 Erste Anordnungen 3.6.2 Einsatz von Zinkbromidlösungen 3.6.3 Fluoreszenz von Saturnpartikeln bei verschiedenen Flüssigkeitsgemischen 3.6.4 Fluoreszenz der Goldkappen 3.6.5 Flüssigkeitsmeniskus in den Probengefäßen 3.6.6 Messung an der Flüssig-Flüssig-Grenzfläche 3.6.7 Schallunterstützte Anordnung 3.6.8 Mathematische Beschreibung der Saturnpartikelnetzwerke 4 Zusammenfassung und Ausblick 5 Experimenteller Teil 5.1 Eingesetzte Chemikalien 5.2 Verwendete Geräte 5.3 Partikelsynthese und -oberflächenmodifikation 5.3.1 Herstellung von Siliziumdioxidpartikeln im Submikrometermaßstab 5.3.2 Herstellung von Polystyrolpartikeln im Mikrometermaßstab 5.3.3 Oberflächenmodifizierung von Glaspartikeln mit Silanen 5.4 Saturnpartikel durch schrittweises Einsinken in ein Polymer 5.5 Saturnpartikel durch Beschichtung mit Gold und graduelles Ätzen 5.6 Saturnpartikel mit geätztem Ring mit Ätzzelle 5.6.1 Pickering-Membranen in einem Rollrandgläschen 5.6.2 Pickering-Membranen in der Permeationsapparatur und Permeationsuntersuchungen 5.7 Saturnpartikeln über Float-Casting 5.7.1 Glaspartikel, Supelco Glass Beads 5.7.2 Siliziumdioxidpartikel, Stöberpartikel 5.7.3 Silsesquioxanpartikel, Tospearls 5.8 Kontaktwinkelmessungen 5.8.1 Kontaktwinkel von Partikeln 5.8.2 Kontaktwinkel von planaren Substraten 5.9 Konfokalmikroskopieaufnahmen 5.9.1 Fluoreszenzlösungen 5.9.2 Konfokalmikroskopieprobengefäße 5.9.3 Subwoofer 5.9.4 Messungen am Konfokalmikroskop 5.10 Rasterelektronenmikroskopieaufnahmen 5.11 Plasmaätzen Literaturverzeichnis Selbstständigkeitserklärung Lebenslauf Veröffentlichungen und Tagungsbeiträge

Mining operations produce a multiscale network of fractures in the coal seams. Permeability evolution in rocks is important for coal bed methane (CBM) and shale gas exploitation as well as for greenhouse gas storage. Therefore, this work presents laboratory tests and a coupled model using PFC3D and FLAC3D to simulate the stress induced permeability evolution in coal samples. Basic mechanical properties are determined via lab testing. The spatial distributions of different components inside the reconstructed samples produce a significant heterogeneity based on CT technique. A newly developed experimental system is employed to perform 3-dimensional loading and to measure the flow rate simultaneously. The evolution process is described by 5 distinct phases in terms of permeability and deformation. Triaxial tests are simulated with PFC3D using a novel flexible wall boundary method. Gas seepage simulations are performed with FLAC3D. Relations between hydraulic properties and fracture data are established. Permeability and volumetric strain show good nonlinear exponential relation after a newly introduced expansion point. Piecewise relations fit the whole process, the expansion point can be treated as critical point. The structural characteristics of the samples influence this relation before and after the expansion point significantly.