Orientador: Rosângela Barros Zanoni Lopes Moreno / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecânica e Instituto de Geociências / Made available in DSpace on 2018-08-22T09:00:58Z (GMT). No. of bitstreams: 1 Lopes_FelipeRobles_M.pdf: 3706160 bytes, checksum: 5656fb6101eaefe1ce42e6acd4bcca9d (MD5) Previous issue date: 2013 / Resumo: A invasão de fluidos de perfuração e suas consequências na produção de petróleo são bem conhecidas e intensivamente discutidas por especialistas. Além disso, a comunidade científica tem buscado o entendimento dos mecanismos de invasão e do retorno de permeabilidade. Este estudo estende investigações anteriores sobre análise de dano e inclui as etapas de invasão de fluido de perfuração e de fluxo reverso de óleo. Foram realizados testes de invasão de fluidos base-água, soluções de goma xantana e de poliacrilamida, à pressão constante, em amostras saturadas com óleo e água conata. Usando um porta-testemunho especial, perfis de saturação e de pressão foram monitorados durante a invasão e o fluxo reverso, permitindo a observação das características do processo de invasão e de remoção do dano de forma dinâmica. A condição de saturação da amostra antes da invasão de polímero, óleo e água conata, permitiu melhorar a representatividade de um reservatório de petróleo. O monitoramento da pressão ao longo da direção de escoamento e varreduras de Raios-X combinados com o balanço de massa de fluidos injetados e produzidos permitiu observar o avanço do fluido invasor. Durante o fluxo reverso foi possível acompanhar dinamicamente a mudança de permeabilidade da região invadida. As principais contribuições deste estudo referem-se à análise do retorno de permeabilidade devido à produção de óleo em uma região danificada pela invasão do fluido de perfuração, bem como a influência da presença de água conata nestes processos / Abstract: Invasion of drilling fluids and their effects on oil production are well known and have been extensively discussed by experts. Furthermore, the scientific community has invested a lot of effort into understanding the mechanisms of invasion and permeability restoration. This study extends previous investigations and includes both invasion and back flow evaluation conditions. Test sample, initially at connate water condition, were submitted to constant pressure displacement. Using a special core holder, saturation and pressure profiles were monitored during overbalance pressure invasion and oil back flow. Monitored data has allowed observing the formation damage characteristics as well as cleaning dynamics. In this work, polymer injection into the sample at residual water saturation has improved the reservoir representation. The pressures data, from the taps along the core, X-Ray data and also the mass balance allow the author to follow the invasive fluid going through the core. Additional insights about dynamic mechanisms were also discussed based on a large quantity of monitored data. During the back flow was possible to dynamically monitor the change of permeability of the invaded region. The main contributions of this study are related to the analysis of the permeability restoration due to oil natural cleanup of the region damage by drill in fluid. The influence of connate water in this process was also important / Mestrado / Reservatórios e Gestão / Mestre em Ciências e Engenharia de Petróleo

Porous materials are implemented in several industrial applications such as water desalination, gas separation and pharmaceutical care which they are mainly governed by the pore size and the PSD. Analyzing shale reservoirs are not excluded from these applications and numerous advantages can be gained by evaluating the PSD of a given shale reservoir. Because of the limitations of the conventional characterization techniques, novel methods for characterizing the PSD have to be proposed in order to obtain better characterization results for the porous materials, in general, and shale rocks in particular. Thus, permporosimetry and evapoporometry (EP) technologies were introduced, designed and utilized for evaluating the two key parameters, pore size and pore size distribution. The pore size and PSD profiles of different shale samples from Norway and Argentina were analyzed using these technologies and then confirmed by mercury intrusion porosimeter (MIP). Norway samples showed an average pore diameter of 12.94 nm and 19.22 nm with an average diameter of 13.77 nm and 23.23 nm for Argentina samples using permporosimetry and EP respectively. Both techniques are therefore indicative of the heterogeneity of the shales. The results from permporosimetry are in good agreement with those obtained from MIP technique, but EP for most part over-estimates the average pore size. The divergence of EP results compared to permporosimetry results is referred to the fact that the latter technique measures only the active pores which is not the case with the former technique. Overall, both techniques are complementary to each other which the results from both techniques seem reasonable and reliable and provide two simple techniques to estimate the pore size and pore size distributions for shale rocks.

Control at the molecular level over porous solid-state materials is of prime importance for fine-tuning the local structures, as well as the resultant properties. Traditional porous solid-state materials such as zeolite and activated carbon are the benchmarks in the current market with vital applications in sorption and heterogeneous catalysis. However, the adjustments of pore size and geometry of those materials, which are essential for the broader aspect of modern prominent applications, remain challenging. Reticular chemistry has emerged as a dominant tool toward the ‘designed syntheses’ of porous crystalline frameworks (e.g. metal-organic frameworks (MOFs)) with a specific pore system. This dissertation illustrates the power of reticular chemistry and its use in the directional assembly of highly coordinated MOF materials, as well as their potential applications such as gas storage, natural gas upgrading, and light hydrocarbon separation. Highly connected minimal edge-transitive derived and related nets, obtained via the deconstruction of nodes of the edge-transitive nets, are suitable blueprints and can potentially be deployed in the future ‘designed syntheses’ of MOFs. The further employment of the conceptual net-coded building units (e.g. highly connected MBBs and edge-transitive SBLs) in the practical reticular synthesis results in the rational design and construction of functional MOF platforms like shp-, alb-, kce-, kex- and eea- MOFs. In addition, the isoreticular synthesis of Al-cea-MOF-2 with functionalized pendant acid moieties inside pore channels in comparison to the parent Al-cea-MOF-1 led to enhanced light hydrocarbons separation performance. Moreover, controlling the molecular defects in Zr-fum-fcu-MOFs resulted in the development of an ultramicroporous adsorbent with an engineered aperture size for the highly efficient separation of butane/iso-butane.

Many structural acoustic and vibration designs rely extensively on materials that are light-weight, stiff, and highly damped. Advanced materials such as metallic foams can be engineered to achieve these properties in order to control sound and vibration for a variety of aerospace, maritime, and ground transportation applications. In this work, the structural and acoustic properties of commercially available and digitally designed metallic foams are analyzed through numerical and experimental methods. Furthermore as a post-manufacturing process, metallic foams can be engineered in order to preferentially alter the microstructure and achieve material property enhancements. In this work, the following engineering methods are proposed and investigated: plastic deformation and material saturation. When a metallic foam is plastically deformed, the foam's porosity and pore shape are dramatically altered. This transformation in microstructure can lead directly to changes in bulk properties. In this work, a method for triaxial hydrostatic compression of metallic foams is proposed and demonstrated experimentally. The structural properties of transformed foams are tested using a load cell with digital image correlation. Transformed foams exhibit higher compliance, higher toughness, and a reduced Poisson ratio. Measurement and analysis of acoustic properties indicate that the transformed foams can absorb significantly more sound than the conventional samples of equal thickness in the test range of 0.25 - 4.50 kHz. Due to their open-cell microstructure, metallic foams can be filled with saturating materials. In this work, metallic foams saturated with viscous liquids are investigated for reducing vibration transmissibility in a structure. For the best performing saturated foam subject to a transient excitation, an order of magnitude increase in damping ratio is measured. Additionally, a composite foam (consisting of metallic foam saturated with polyurethane foam) is fabricated to enhance acoustic properties. For the best performing composite foam at normal incidence, the sound absorption coefficient is improved by a factor of 6 near 0.60 kHz and by a factor of 2 up to 4.5 kHz. Lastly, two methods for estimating acoustic absorption in metallic foams are presented which utilize finite element analysis and boundary layer theory. The proposed methods are discussed for commercially available foams as well as for representative digital designs. Limitations and assumptions of the methods pertaining to size scales and boundary layer features are addressed.

Title: The Preparation of Porous Materials for Radionuclide Capture Author: Bc. Anna Bajzíková Curriculum: Teaching of Chemistry and Biology for Secondary Schools Type of thesis: Master's Department: Department of Teaching and Didactics of Chemistry, Faculty of Science, Charles University in Prague Elaborated: Department of Nuclear Chemistry, Faculty of Nuclear Sciences and Psysical Engineering, Czech Technical University in Prague Advisor: Doc. Ing. Stanislav Smrček, CSc. Consultant: RNDr. Ján Kozempel, Ph.D. Abstract: The use of radionuclides is still increasing and with it also increases the amount of radioactive waste and this waste have to be processed. This thesis is focused on the preparation, characterization and testing of porous materials which could be used for the process of this waste. There were prepared and characterized materials based on silica and zirkonia with a modified surface. For the modification were used styren with divinilbenzene, polyacrilonitrile and diglycolamides at different configurations of these materials. Furthermore, there were prepared materials based on hydroxyapatite and its modifications. Prepared sorbents were tested for radionuclide capture - flow through the column and also in the static experiments. The capture of 227Ac and its daughter's radionuclides...

Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Civil Engineering, 1982. / MICROFICHE COPY AVAILABLE IN ARCHIVES AND ENGINEERING. / Bibliography: leaves 211-213. / by Si, Boon-Ing. / M.S.

No description available.

In this master thesis project, attempts were made to synthesize, pore size tailor, and characterize ZIF-8 and several mixed-linker ZIF structures to improve capture of the greenhouse gasses CH4, CO2, and SF6. Three experimental linkers, 2-methylbenzimidazole, 2-aminobenzimidazole, and 5-nitrobenzimidazole were chosen to gradually substitute 2-methylimidazole as the linker in ZIF-8.  This substitution was intended to gradually reduce pore sizes and possibly adding functionality to the apertures present in ZIF-8 (three different series). The methods of synthesis were first evaluated by performance and modified. Three series of ZIF-hybrids were then synthesized and characterized using PXRD, FTIR, 1HNMR, SEM, extensive sorption measurements, and subsequent modeling to evaluate any success tailoring the hybrid ZIF apertures to increase gas sorption. After modifying synthesis conditions, the undertaking was deemed a success as all three linkers were possible to incorporate to some degree. Hybrid ZIFs were mostly XRD-crystalline. The cleaning process was deemed sufficient. Linker incorporation was not complete but increased with the added linker. Sodalite topology was confirmed in ZIF-8 samples and confirmed as modified in hybrid ZIFs. The hybrid ZIFs did indeed show altered sorption results and surprisingly promising results regarding gas selectivity (favoring sorption of one gas over that of another).

The primary objective of this research is to investigate the morphological and mechanical properties of composite materials and porous materials prepared by thermally induced phase separation. High melting crystallizable diluents were mixed with polymers so that the phase separation would be induced by the solidification of the diluents upon cooling. Theoretical phase diagrams were calculated using Flory-Huggins solution thermodynamics which show good agreement with the experimental results. Porous materials were prepared by the extraction of the crystallized diluents after cooling the mixtures (hexamethylbenzene/polyethylene and pyrene/polyethylene). Anisotropic structures show strong dependence on the identity of the diluents and the composition of the mixtures. Anisotropic crystal growth of the diluents was studied in terms of thermodynamics and kinetics using DSC, optical microscopy and SEM. Microstructures of the porous materials were explained in terms of supercooling and dendritic solidification. Dual functionality of the crystallizable diluents for composite materials was evaluated using isotactic polypropylene (iPP) and compatible diluents that crystallize upon cooling. The selected diluents form homogeneous mixtures with iPP at high temperature and lower the viscosity (improved processability), which undergo phase separation upon cooling to form solid particles that function as a toughening agent at room temperature. Tensile properties and morphology of the composites showed that organic crystalline particles have the similar effect as rigid particles to increase toughness; de-wetting between the particle and iPP matrix occurs at the early stage of deformation, followed by unhindered plastic flow that consumes significant amount of fracture energy. The effect of the diluents, however, strongly depends on the identity of the diluents that interact with the iPP during solidification step, which was demonstrated by comparing tetrabromobisphenol-A and phthalic anhydride. A simple method to prepare composite surfaces that can change the wettability in response to the temperature change was proposed and evaluated. Composite surfaces prepared by nanoporous alumina templates filled with polymers showed surface morphology and wettability that depend on temperature. This effect is attributed to the significant difference in thermal conductivity and the thermal expansion coefficient between the alumina and the polymers. The reversibility in thermal response depends on the properties of the polymers.

A computer model has been developed to analyze the flow of a dissociating gas through a porous metal matrix. The program predicts the transient temperature distributions through the coolant gas and matrix along with the pressure distribution and mass flow rate. The differential equations used in developing the program are documented in the literature of represent logical extensions of documented equations. The derivation of the finite difference equations is presented. Comparisons of experimental data with computer predictions are shown and indicate that the predictions fall within the experimental error in the data. A source listing of the computer program is contained in the Appendix.