Charles University in Prague, Faculty of Pharmacy in Hradci Králové Department of: Department of Pharmaceutical Technology Consultant: Mgr. Pavel Ondrejček, Ph.D. Student: Nikola Marcinková Title of Thesis: The influence of the die size on the compaction process This diploma thesis is focused on exploration the influence of the die size on the compaction process. That was evaluated by parameters of three-exponential equation. Compressibility was studied by using force-displacement record. In this work was also observed an effect of die size on the tensile strength. In processing the experimental part of this work were used four different model materials. Microcrystalline cellulose and dicalcium phosphate are used as model fillers and theophylline and paracetamol as model active substances. Compaction of these materials was carried out in dies of size 7 mm, 9 mm, 11 mm, 13 mm and 15 mm. The results of the work showed that the die size significantly affects all parameters force-displacement record. With the growing size of the die there was a reduction of energy parameters. Most of the compaction parameters were statistically influenced. Increasing die size caused reducing volume reduction and energy consumption and increased speed of volume reduction at the stage of pre- compression and elastic...

Charles University in Prague, Faculty of Pharmacy in Hradec Králové Department of Pharmaceutical Technology Consultant: Mgr. Pavel Ondrejček, Ph.D. Student: Simona Berková Title of Thesis: The evaluation of compressibility of the mixtures pellets and microcrystalline cellulose This thesis is focused on the evaluation of powdered microcrystalline cellulose, pellets and mixtures thereof. Comprecel 102 was used as powdered microcrystalline cellulose. The used pellets were commercially available pellets Cellets 100 made of microcrystalline cellulose. The flow properties of used materials and their mixtures were evaluated by using the angle of repose, flow through orifice and Hausner ratio methods. Further the compressibility was evaluated using the force-displacement record. For the evaluation of compaction proces the three exponential compaction was used. Finally the radial tablet strength and tablet friability was tested. The results showed, that the flow properties improved with an increasing amount of pellets in mixture. I tis due to higher bulk and tapped density and also narrower particle size distribution, smoother surface and the regular shape of used pellets. The parameters of the force-displacement method showed different compressibility of used tabletting mixtures. The evaluation of...

Charles University in Prague, Faculty of Pharmacy in Hradec Králové Department of: Pharmaceutical technology Consultant: Mgr. Petra Svačinová, Ph.D. Student: Michaela Přeučilová Title of Thesis: A comparison of viscoelastic properties of mixtures of lactose and different lubricants using the stress relaxation test This diploma thesis deals with viscoelastic properties of pharmaceutical excipients and tensile strength of tablets made of these excipients. Theoretical part is dedicated to description of lactose and lubricants, further the tablets compressibility and compression energy profile are described. The end of theoretical part deals with the stress relaxation test, with evaluation methods and the stress relaxation test influence on lactose tablets with different types of lubricants as well. The experimental part deals with the evaluation of the viscoelastic properties of two types of lactose and their mixtures with different types of lubricants at concentration of 1%. These characteristics were evaluated by stress relaxation test. All tablets were compressed by compression forces of 13 kN and 15 kN with dwell time 180 seconds. The study was about differences between two types of lactose, effect of lubricants and effect of two different compression forces on parameters of elasticity A1 -A3 and...

Charles University in Prague, Faculty of Pharmacy in Hradec Králové Department of: Pharmaceutical technology Consultant: Mgr. Petra Svačinová, Ph.D. Student: Straková Markéta Title of Thesis: The influence of dwell time on the parameters of the stress relaxation test for lactose and calcium hydrogen phosphate The aim of this thesis is to find out viscoelastic properties of pharmaceutical excipients and to evaluate the tensile strength of tablets made of them. The theoretical part describes used materials, these are lactose, calcium hydrogen phosphate and magnesium stearate. The thesis also deals with the stress relaxation test, its evaluation and usage. Tensile strength, calculation and various factors that affect tensile strength are described in the text. The experimental part deals with viscoelastic properties of used materials and their mixtures with lubricant using the stress relaxation test. Different dwell times (60 s, 120 s, 180 s, 240 s, 300 s, 360 s, 420 s, 480 s, 540 s, 600 s) were used for individual measurements. The relation between elasticity parameters (A1, A2, A3) and plasticity parameters (P1, P2, P3) depending on the dwell time was investigated. As for calcium hydrogen phosphate, the dwell time 180 - 240 seconds was found as the most appropriate. As for lactose, the optimum dwell...

Charles University in Prague, Faculty of Pharmacy in Hradec Králové Department of Pharmaceutical Technology Consultant: Mgr. Pavel Ondrejček, Ph.D. Student: Žofie Trpělková Title: A study of a compaction process of microcrystalline cellulose pellets This work is aimed at the comparison of two types of microcrystalline cellulose (Comprecel 102 a Avicel PH-200) with two types of pellets made of microcrystalline cellulose (Cellets 100 a Cellets 200). Important properties for the compaction into tablets were analyzed in these materials. The particle size distribution, the content of moisture, the bulk and tapped density, the flowability, the angle of repose and the Hausner ratio were evaluated. Furthermore, the compaction process was described by using the force displacement method and the three-exponential equation. Finally, the radial strength and the friability of tablets prepared by using two different compaction forces were evaluated. The results proved that both types of pellets have much better flow properties than powdered microcrystalline celluloses. This is primarily caused by the narrow particle size distribution, higher bulk and tapped density and the significantly smoother surface of pellets. Better flow properties of the pellets also influenced the parameters of the force-displacement...

Charles University in Prague, Faculty of Pharmacy in Hradec Králové Department of: Pharmaceutical technology Consultant: Mgr. Svačinová Petra, Ph.D. Student: Hamplová Kateřina Title of Thesis: The influence of the dwell time on the parameters of the stress relaxation test for microcrystalline cellulose and starch. This thesis is focused on the viscoelastic properties of pharmaceutical excipients and the tensile strength of tablets. The theoretical part describes used materials. Microcrystalline cellulose and starch were used as fillers and magnesium stearate at concentration of 1% was used as lubricant. The stress relaxation test and its evaluation and utilization not only in pharmacy is described as well as the tensile strength of tablets. The experimental part deals with the viscoelastic properties of used materials and their mixtures with lubricant. These properties were evaluated using the stress relaxation test. At maximum compression force of 10 kN the length of dwell time was changed (60 s, 120 s, 180 s, 240 s, 300 s, 360 s, 420 s, 480 s, 540 s, 600 s). For derived parameters of elasticity A1-3 and plasticity P1-3 the dependence on the length of dwell time was evaluated. Parameter A1 increases with increasing dwell time for all substances. For parameters A2, A3, the dependence on the dwell...

<div>Due to the instabilities that may occur in dc power systems with regulated power electronic loads such as those used in aircraft, ships, as well as terrestrial vehicles, many analysis techniques and design methodologies have been developed to ensure stable operation following small disturbances starting from normal operating conditions. However, these techniques do not necessarily guarantee large-displacement</div><div>stability following major disturbances such as faults, regenerative operation, pulsed loads, and/or loss of generating capacity. In this thesis, a formal mathematical definition of large-displacement stability is described and the analytical conditions needed to guarantee large-displacement stability are investigated for a notional dc power system. It is shown possible to guarantee large-displacement stability for any piecewise continuous value of load power provided it is bounded by the peak rating of the dc source.</div>

Gender-based violence (GBV) and violence against children are pervasive and destructive globally, but the exacerbation of violence in emergency contexts makes addressing them an urgent priority in humanitarian action. However, despite recognition of overlapping risks and intervention opportunities, child protection programming and GBV programming have hitherto followed discrete trajectories, resulting in adolescent (aged between 10 and 19 years) girls falling between the domains, despite their heightened vulnerability to GBV. This research explores how humanitarian protection interventions address GBV against displaced adolescent girls in Jordan. Data is collected using detailed, semi-structured interviews with four specialist humanitarian practitioners from leading organisations in child protection and GBV programming within the refugee response in Jordan. Qualitative, grounded coding and analysis is conducted on the transcribed data to identify key themes and patterns. The findings report child marriage, domestic violence and sexual violence as the most prevalent forms of GBV against adolescents. The social ecology of the girls is explored and salient risk factors at each level are identified, including lack of awareness, cultural norms and stigma, and absence of data information to direct programming. Corresponding protection interventions, including case-management, capacity-building of service providers and awareness-raising are identified, and the limited extent to which they empower adolescent girls is debated. Finally, the nexus between child protection and GBV programming is discussed, and key challenges, including coordination between child protection and GBV policies, campaigns, services and actors, decreasing funding and nationalisation of services, an absence of meaningful participation of adolescent girls in programming, and the organisations’ issue-focused approach, are identified and explored in the context of empowerment of adolescent girls. The research concludes that addressing GBV by meaningful participation of adolescents, adopting rights-based approaches, and proactive coordination of protection actors, is essential for the empowerment of adolescent girls to be agents of their own protection.

Les travaux présentés dans cette thèse concernent l’utilisation de données de télédétection inédites pour le suivi des glaciers du massif du Mont Blanc : les images radar à synthèse d’ouverture Haute Résolution (HR) du satellite TerraSAR-X et les prises de vue HR d’un appareil photo numérique automatique. Cette thèse s’attache à montrer l’apport de ces sources d’informations hétérogènes pour mesurer le déplacement de surface des glaciers alpins. Dans cette optique, un examen des méthodes de mesure de déplacement spécifiques à chacun des deux types d’images est réalisé. Deux approches sont alors explorées : la mesure de déplacement monosource dans la géométrie propre à chaque capteur et la mesure de déplacement multisource via des combinaisons intra-capteur et inter-capteur. Alors que l’approche monosource fournit uniquement des mesures 2D du déplacement, les mesures multisources permettent pour la première fois d’estimer des champs de déplacement 3D de la surface des glaciers du Mont Blanc. Les mesures ont été réalisées sur plusieurs séries temporelles d’images couvrant la période 2008-2009 pour quatre glaciers du massif du Mont Blanc (Argentière, Mer de Glace/Leschaux, Bossons et Taconnaz). Dans le contexte du changement climatique, ces mesures de déplacement de surface fournissent une donnée intéressante en glaciologie pour contraindre les modèles numériques d’écoulement et d’évolution des glaciers. / The works presented in this PhD thesis focuses on the use of new remote sensing data for "massif du Mont Blanc" glaciers’ monitoring: High Resolution (HR) synthetic aperture radar images of TerraSAR-X satellite and HR shooting of the automatic digital camera. This thesis will show the contribution of this heterogeneous information to the measurement of the surface displacement of alpine glacier. For this purpose, a review of displacement measurement methods specific to each of the two types of image is proposed. Then two approaches are explored: the mono-source displacement measurement in the geometry for each sensor and the multi-source displacement measurement via intra-sensor and inter-sensor combinations. While the mono-source approach provides only 2D displacement measurements, multi-source measurements allow, for the first time, the estimation of 3D surface displacement fields of the Mont Blanc glaciers. The measurements were performed on several image time series covering the period 2008-2009 for four Mont Blanc glaciers (Argentière, Mer de Glace/Leschaux, Bossons et Taconnaz). In the context of global warming, these surface displacement measurements provide interesting data in the glaciology domain in order to constrain flow and evolution digital models.

[pt] O escoamento de emulsões é encontrado em diversos processos de recuperação e produção de petróleo. O escoamento de emulsões em meios porosos depende de diversos parâmetros como a relação do tamanho das gotas ao tamanho dos poros, a razão de viscosidades, a vazão volumétrica e o efeito destes parâmetros ainda não é bem compreendido. Uma análise detalhada na escala microscópica dos fenômenos envolvidos se faz essencial para a melhora do entendimento completo do escoamento de emulsões em um reservatório. Isto permitiria o desenvolvimento de melhores modelos de simulação para o escoamento multifísico em meios porosos. Neste trabalho, o escoamento de emulsões óleo-água através de um capilar com garganta foi estudado através de experimentos e teoria. A análise experimental consistiu da visualização sob um microscópio do escoamento e da medição da queda de pressão em função da vazão para diferentes emulsões. A análise teórica englobou o estudo do escoamento em regime permanente de uma gota de óleo imersa em água através de um capilar e o estudo do escoamento transiente da mesma gota através de um capilar com uma garganta. Os resultados mostram que os modelos de escoamento de emulsões em meios porosos não devem ser baseados em propriedades macroscópicas da emulsão quando o tamanho das gotas da fase dispersa for da mesma ordem de grandeza do tamanho dos poros. Neste caso, a queda de pressão é função da tensão interfacial, a razão de viscosidades, a vazão e a razão entre o tamanho das gotas e o diâmetro do poro. Os resultados apresentados neste trabalho podem ser usados no projeto de emulsões apropriadas para controle de mobilidade em operações de recuperação avançada através de injeção de emulsões. / [en] Flow of emulsions is found in many petroleum recovery and production processes and it is often referred to in the context of tertiary oil recovery. The characteristics of emulsion flow in porous media depend on several parameters such as medium drop size to pore size ratio, viscosity ratio, flow rate and the effect of these parameters is far from being entirely understood. A detailed analysis at a microscopic scale of the flow is essential to improve the understanding of flow of an emulsion in a reservoir. This would lead to the development of better simulation models, henceforth increasing the predictability capability of reservoir simulators for enhanced oil recovery applications. In this work, flow of oil-water emulsions through constricted capillaries, used as model for the geometry inside a porous media, is studied experimentally and theoretically. The experimental approach consisted of measuring pressure drop response as a function of flow rate for different emulsions and visualizing the flow under an optical microscope to understand the phenomena involved. The theoretical approach is divided in two parts. First, the immiscible steady flow of a infinite single drop suspended in an less viscous fluid through a capillary was analyzed by solving the Navier- Stokes equations with the appropriate boundary conditions for free-surface flow. The second part of the theoretical analysis consisted of solving the transient flow of a drop suspended in a less viscous fluid through a capillary with a constriction. It is shown the effect of capillary number and viscosity ratio over the main responses of the flow. The results show that models of emulsion flow in a porous media cannot be based on the macroscopic properties of the emulsion when the drop diameter is of the same order of magnitude as the pore throat diameter. In this case flow rate-pressure drop is a strong function of the interfacial tension, viscosity ratio, flow rate and drop to pore size ratio. The results can be used to design appropriate emulsions to control the water mobility during EOR operations by emulsion injection.