A model for the evaluation of CO2-EOR projects has been developed. This model includes both reservoir simulation to handle reservoir properties, fluid flow and injection and production schedules, and a numerical economic model that generates a monthly cash flow stream from the outputs of the reservoir model. This model is general enough to be used with any project and provide a solid common basis to all of them. This model was used to evaluate CO2-EOR injection and production strategies and develop an optimization workflow. Producer constraints (maximum oil and gas production rates) should be optimized first to generate a reference case. Further improvements can then be obtained by optimizing the injection starting date and the injection plateau rate. Investigation of sensitivity of CO2-EOR to the presence of an aquifer showed that CO2 injection can limit water influx in the reservoir and is beneficial to recovery, even with a strong water drive. The influence of some key parameters was evaluated: the producer should be completed in the top part of the reservoir, while the injector should be completed over the entire thickness; it is recommended but not mandatory that the injection should start as early as possible to allow for lower water cut limit. Finally, the sensitivity of the economics of the projects to some key parameters was evaluated. The most influent parameter is by far the oil price, but other parameters such as the CO2 source to field distance, the pipeline cost scenario, the CO2 source type or the CO2 market price have roughly the same influence. It is therefore possible to offset an increase of one of them by reducing another.

Metal-organic frameworks (MOFs), a new class of porous solids comprised of metal-containing nodes linked by organic ligands, have become promising materials for gas separations. In particular, their flexible chemistry makes them attractive for CO2 capture from flue gas streams in post-combustion plants. Although numerous efforts have been exerted on the investigation of MOFs for CO2 capture, the exploration of the effects from coexisting components present in very dilute proportions in flue gases is limited because of the experimental difficulty to determine the coadsorption of CO2 with trace components. In this regard, molecular simulations show superiority. In this study, molecular simulations are used to estimate the influence of impurities: water, O2, and SO2 on post-combustion CO2 capture in MOFs. Firstly, two MOFs with coordinatively unsaturated metal sites (CUMs), HKUST-1 and Mg-MOF-74 are explored. Increase of CO2 adsorption is observed for hydrated HKUST-1; on the contrary, the opposite water adsorption behavior is observed in hydrated Mg-MOF-74, leading to decrease of CO2 adsorption. Further, water effects on CO2 capture in M-HKUST1 (M = Mg, Zn, Co, Ni) are evaluated to test whether comparing the binding energy could be a general method to evaluate water effects in MOFs with CUMs. It is found that the method works well for Zn-, Co-, and Ni-HKUST1 but partially for Mg-HKUST1. In addition, the effects of O2 and SO2 on CO2 capture in MOFs are also investigated for the first time, showing that the effects of O2 may be negligible but SO2 has negative effects in the CO2 capture process in HKUST-1 systems. Secondly, the influences of water on CO2 capture in three UiO-66 MOFs with functional groups, –NH2, –OH and –Br are explored, respectively. For UiO-66-NH2 and -OH, the presence of water lowers CO2 adsorption significantly; in contrast, water shows much smaller effects in UiO-66-Br. Moreover, the presence of SO2 decreases water adsorption but enhances CO2 uptakes slightly in both UiO-66-NH2 and -Br. Finally, the effects of impurities on CO2 capture in a MOF with suitable pore size (PCN-200) are analyzed. The adsorption of both CO2 and N2 decrease substantially even with 1% water present in the mixture. In addition, the presence of low SO2 does not show obvious effect in PCN-200. However, a lower CO2 adsorption is observed for a mixture with a high SO2 content. In collaboration with experimental groups, the performances of three new MOFs in CO2 capture are evaluated using molecular simulations. The computational results demonstrate the feasibility of precisely designing single-molecule traps (SMT) for CO2 capture. Also, a multi-functional MOF with micro-porosity, open Cu2+ sites and amine groups has also proved computationally the selective adsorption of CO2 over CH4 and N2. Last, we demonstrate that charge separation is an effective strategy for improving CO2 capture in MOFs.

A dynamic MEA absorption process model has been developed to study the operability of this process in a dynamic fashion and to develop a control strategy to maintain the operation of the MEA scrubbing CO2 capture process in the presence of the external perturbations that may arise from the transient operation of the power plant. The novelty in this work is that a mechanistic model based on the conservation laws of mass and energy have been developed for the complete MEA absorption process. The model developed in this work was implemented in gPROMS. The process response of the key output variables to changes in the key input process variables, i.e., the flue gas flow rate and the reboiler heat duty, are presented and discussed in this study. In order to represent the actual operation of a power plant, the dynamic response of the MEA absorption process to a sinusoidal change in the flue gas flow rate was also considered in the present analysis. The mechanistic dynamic model was applied to develop a basic feedback control strategy. The implementation of a control strategy was tested by changing the operating conditions for the flue gas flow rate. The controlled variables, i.e., the percentage of CO2 absorbed in the absorber column and the reboiler temperature, were maintained around their nominal set point values by manipulating the valve stem positions, which determine the lean solvent feed flow rate at the top of the absorber column, and the reboiler heat duty, respectively. For the sinusoidal test, the amplitude of the oscillations observed for the controlled variables was smaller than those observed for the open-loop tests. This is because the variability of the controlled variables was transferred to the manipulated variable in the closed loop. The mechanistic dynamic model developed in this process can be potentially used as a practical tool that can provide insight regarding the dynamic operation of MEA absorption process. The model developed in this work can also be used as a basis to develop other studies related to the operability, controllability and dynamic flexibility of this process.

This study extends the methodology for the delineation of capture zones to base flow contribution areas for stream reaches under the assumption of constant average annual base flow in the stream. The methodology is applied to the Alder Creek watershed in southwestern Ontario, using three different numerical models. The three numerical models chosen for this research were Visual Modflow, Watflow and HydroGeoSphere. Capture zones were delineated for three different stream segments with reverse particle tracking and reverse transport. The modelling results showed that capture zones delineated for streams are sensitive to the discretization scheme and the different processes considered (i.e. unsaturated zone, surface flow). It is impossible to predict the size, shape and direction of the capture zones delineated based on the model selected. Also, capture zones for different stream segments will reach steady-state at different times. In addition, capture zones are highly sensitive to differences in hydraulic conductivity due to calibration. It was found that finite element based integrated groundwater - surface water models such as HydroGeoSphere are advantageous for the delineation of capture zones for streams. Capture zones created for streams are subject to greater uncertainty than capture zones created for extraction wells. This is because the hydraulic gradients for natural features are very small compared to those for wells. Therefore, numerical and calibration errors can be the same order of magnitude as the gradients that are being modelled. Because of this greater uncertainty, it is recommended that particle tracking and reverse transport always be used together when delineating capture zones for stream reaches. It is uncertain which probability contour to choose when the capture zone is delineated by reverse transport alone. The reverse particle tracks help choose the appropriate probability contour to represent the stream capture zone.

<p>The odd &ndash / odd Tl nuclei with A &ge / 190 have moderate oblate nuclear deformation and show rotational bands built on different quasiparticle excitations. Several phenomena, not yet fully understood, were observed in these nuclei, such as large signature splitting in the yrast band (built on a &pi / h9/2&otimes / &nu / i13/2 configuration), possible non &ndash / axiality of the nuclear shape, etc. In this work the high &ndash / spin states in 194Tl were studied. The 194Tl nuclei were produced in the 181Ta (18O, 5n) 194Tl reaction at a beam energy of 93 MeV and the &gamma / - rays were detected using the AFRODITE array. The obtained extended level scheme of 194Tl is presented and discussed in this work. CSM (Cranking shell model) and TRS (Total Routhians Surface) models were both applied to interpret the results for band 1. The results were compared with the neighboring isotone 193Hg.</p>

Carbon dioxide CO₂capture through hydrate formation is a novel technology under consideration as an efficient means of separating CO₂from flue/fuel gas mixtures for sequestration and enhanced oil recovery operations. This thesis examines post-combustion capture of CO₂from fossil-fuel power plant flue-gas streams through hydrate formation in a silica gel column. Power plant flue-gas contains essentially CO₂and nitrogen (N2) after suitable pre-treatment steps, thus a model flue-gas comprising 17% co₂and 83% N2 was used in the study. Previous studies employed a stirred-tank reactor to achieve water-gas contact for formation of hydrates; recent microscopic studies involved using water dispersed in silica gel to react with gas, showing potential for improved hydrate formation rates without the need for agitation. This study focuses on macroscopic kinetics of hydrate formation in silica gel to evaluate hydrate formation rates, CO₂separation efficiency and determining optimal silica gel properties as a basis for a CO2 capture process. Spherical silica gels with 30.0 and 100.0 nm pore sizes and 40-75 and 75-200 μm particle sizes were studied to determine pore size and particle size effects on hydrate formation. 100.0 nm pores achieved higher gas uptake and CO₂recovery over the 30.0 nm case. Improved CO₂separation was obtained when 75-200 μm particles with 100.0 nm pores were used. The two effects observed are due to improved gas diffusion occurring with larger pore and particle size, favouring increased hydrate formation. Compared to stirred-tank experiments, results in this study show a near four-fold increase in moles of gas incorporated in the hydrate per mole of water, showing that improved water-to-hydrate conversion is obtained with pore-dispersed water. At similar experimental conditions, CO₂recovery improved from 42% for stirred-tank studies to 51% for the optimum silica (100.0 nm 75-200 μm) determined in this study. Finally, effects of tetrahydrofuran (THF) - an additive that reduces operating pressure were evaluated. Experiments with 1 mol% THF, the optimum determined from previous stirred tank studies, showed improved gas consumption in silica but reduced CO₂recovery, indicating that the optimum concentration for use in silica is different from that in stirred-tank experiments.

This thesis examines the concepts of value creation, capture and exchange in limiting the liability of newness for nonprofit museums entering the sector. There has been considerable examination of cultural value in relation to museums. However, little is known about how value is created, captured and exchanged for stakeholders in new museums. It is posited that value creation, capture and exchange constitute a value cycle. Through this value cycle management in new museums detects and limits the liability of newness. The ability to detect and limit the liability of newness enables the continuation of the museum. If the liability of newness is not limited, it may mean that a new museum exits the sector or is transformed. The concept of a value cycle is derived from an examination of the nonprofit management literature, aspects of the for-profit management literature and the arts and museum management literature. Value creation is a key concept in the three literature areas. Value creation in this context, is specifically defined as the worth of the physical manifestation of the museum. It resides in the building and the collection, services and programs within the building. It is suggested that this value needs to be transformed and consumed by a range of stakeholders. The transformation of value creation is denoted as value capture. Value capture is the appeal of programs, projects and activities. Value capture includes how well the products and services align with particular stakeholders, how accountable the managers are to stakeholders and how products and services are consumed by stakeholders. The measure of how managers have been able to capture value is in the realm of value exchange. Value exchange is the merit of programs, projects and activities. Value exchange is in the form of revenue raised through sponsorship; continuation of revenue investment by the principal stakeholder, the state; time and money transacted by visitors; and intangible exchange such as leadership and reputation enhancement through collaborations. A Value Cycle Framework of New Entrant Museums is then developed as a working analytical tool to assess how the value cycle operates and how the liability of newness is detected and limited by museum management. x The Value Cycle Framework is used to assess four cases. These case studies include the National Museum of Australia as a purpose built new entrant; the Australian National Maritime Museum as a purpose built new entrant; the Mint as a recycled new entrant; and the Earth Exchange as a refurbished new entrant. Each case is assessed discretely using secondary and primary source material and analysing qualitative data generated from interviews with key stakeholders. The cases are then compared in order to track similarities and differences in relation to value creation, capture and exchange. The research findings suggest that a value cycle is operating in relation to new entrant museums. This value cycle is dynamic and non-sequential. Until value creation is floated for a range of stakeholders it is difficult for managers to know the worth of their content, location or their building. Value creation is a nominal starting point, signifying the arrival of a new entrant in the museum marketplace. However, value capture is the zone that is the most vulnerable and volatile for managers of new museums. Typically in these case studies value capture includes a disruptive episode, such as a review process that indicates the liability of newness. Managers within the museum who can respond and resolve contradictions between museological beliefs and the demands of stakeholders (and in so doing limit the liability of newness) are likely to continue museum operations. Senior executives who find such reconciliation more difficult, jeopardize the future operations of the museum to such an extent that the museums close or are transformed within the museum sector. Through these four case studies a revised Value Cycle Framework is developed as an analytical device. This analytical framework can assist in understanding the processes involved in new entry for museums.

Thesis (M.S.)--Texas State University-San Marcos, 2007. / Vita. Includes bibliographical references (leaves 73-75).

Thesis (M.S.)--Texas State University-San Marcos, 2007. / Vita. Includes bibliographical references (leaves 73-75).

Thesis (Ph.D.)--University of Adelaide, Dept. of Chemistry, 2001. / Bibliography: leaves 178-195.