The purpose of this study was to examine how five African American middle school students, who were displaced by Hurricane Katrina represent their literacy experiences before, during, and after their displacement. Specifically, the two research questions were: (a) What are the stories that these middle school students tell about their lives, before, during, and after their displacement, and (b) What do their stories reveal about their literacy experience before, during, and after their displacement? Narrative Inquiry was the chosen methodology for the study, which allowed the participants to tell their experiences from a first-person perspective. It also encouraged the participants to reflect upon these experiences, in order to give meaning to their thoughts and emotions. Employing a critical lens and perspective, I constructed a narrative profile for each participant, which was then analyzed using these methods. Each narrative profile detailed the literacy experiences of the participants before Hurricane Katrina, during the transition period, and current literacy experiences now that the participants are resettled and attending school in the host city. These data were supplemented by archival data such as report cards, individual education plans (IEPs), and Texas Assessment of Knowledge and Skills (TAKS) scores. Data analysis of the five participants’ literacy experiences revealed common themes. These participants have pleasant memories of school literacy before the storm and mentioned “choice” as a component of those experiences. During the transition period, few or no literacy experiences took place. Hence, there were missed opportunities for the participants to use literacy experiences to make connections to their new world. Participants reported current classroom and school experiences were controlled environments that led to controlled literacy experiences. This compartmentalization of literacy experiences is not consistent with the critical literacy perspective adopted in this study. Their interviews suggested that they that they saw no connection between school literacy and their literacy experiences outside school.

<p> When a beam of electromagnetic radiation, limited by an aperture, undergoes total internal reflection, a sideways displacement of the reflected beam results. This displacement is known as the Goos-Hänchen Shift. </p> <p> In this work the Goos-Hänchen Shift is studied with 3.2 cm microwaves. The observed shifts disagree with three existing theories. For this reason a modified theory is developed in this work. The throey regards the beam from a pyramidal horn antenna as a superposition of a large number of plane waves. The shift is calculated on this basis. Agreement between experiment and theory is good. </p> / Thesis / Doctor of Philosophy (PhD)

A new processing technique, known as hydrophobic displacement, was explored as a means of simultaneously removing both mineral matter and surface moisture from coal in a single process. Previous thermodynamic analysis suggests that coal moisture will be spontaneously displaced by any oil with a contact angle greater than ninety degrees in water. Based on these results, six methods of hydrophobic displacement were evaluated: hand shaking, screening, air classification, centrifugation, filtration, and displacement. In the first five methods hydrophobic displacement took place during the cleaning stage. A recyclable non-polar liquid (i.e. pentane) was used to agglomerate coal fines followed by a physical separation step to remove the coal agglomerates from the mineral-laden slurry. Bench-scale tests were performed to identify the conditions required to create stable agglomerates. Only the last method, displacement, did not utilized agglomeration and performed hydrophobic displacement during dewatering, not cleaning. A procedure was also developed for determining moisture content from evaporation curves so that the contents of water and pentane remaining in a sample could be accurately distinguished. Two primary coal samples were evaluated in the test program, i.e., dry pulverized 80 mesh x 0 clean coal and 100 mesh x 0 flotation feed. These samples were further screened or aged (oxidized) to provide additional test samples. The lowest moisture, 7.5%, was achieved with centrifugation of the pulverized 80 mesh x 0 clean coal sample. Centrifugation provided the most reliable separation method since it consistently produced low moisture, high combustible recoveries, and high ash rejections. Hand shaking produced the next lowest moisture at 16.2%; however, the low moistures were associated with a drop in combustible recovery. There was also a great deal of error in this process due to its arbitrary nature. Factors such as oxidation, size distribution, and contact angle hysteresis influenced the concentrate moistures, regardless of the method utilized. / Master of Science

<p> The regioselectivities of bromination and deuterium exchange of 2-butanone are shown to be the same, under identical conditions. This work firmly establishes that enolization is the rate-determining step for the former reaction, contrary to some recent reports in the literature.</p> <p> The steric effects and activation parameters in the bimolecular nucleophilic displacement reactions of a series of α-haloketones and alkyl halides are shown to be inconsistent with either a bridging or conjugation mechanism for the observed rate enhancements of haloketone over alkyl halide.</p> <p> The stereoelectronic requirements of this mechanism are tested in a system where the stereochemistry is known (cis- and trans-chlorocyclohexanones). The activation parameters suggest that only in the case where the geometry is correct for maximum conjugation (trans-chlorocyclohexanone) is there an appreciable difference in mechanism (stereoelectronically) from displacement at ordinary saturated carbon.</p> / Thesis / Doctor of Philosophy (PhD)

Metallic alloys are important structural and cladding materials for current and future reactors. Understanding radiation-induced damage on metallic alloys is important for maintaining the safety of nuclear reactors. This dissertation mainly focuses on radiation-induced primary damage in iron-based metallic. Systematic molecular dynamics simulations were conducted to study the alloying element effects on the primary damage in Fe-based alloys, including defect production and dislocation loop transformations, and their connections with defect thermodynamics. First, effects of alloying elements on the primary damage in three Fe-based ferritic alloy systems were studied, with a particular focus on the production behaviors of solute interstitials. The production behaviors of solute interstitials include over-production or under-production, compared with their solute concentration in the Fe matrix. The three alloy systems are: (1) a Fe-Cr alloy system; (2) a Fe-Cu alloy system; and (3) an ideal but artificial Fe-Cr alloy system, which is used as a reference system. It is found that the number ratio of solute interstitials to the total interstitials is distinct in these alloys. The solute interstitials are over-produced in the Fe-Cr systems but under-produced in the Fe-Cu system, compared with solute composition in the alloys. The defect formation energies in both dilute and concentrated alloys, interstitial-solute binding energies, liquid diffusivities of Fe and solute atoms, and heat of mixing have been calculated for both Fe-Cr and Fe-Cu alloys. Among these factors, our analysis shows that the relative thermodynamic stability between Fe self-interstitials and solute interstitials plays the most important role on the production behaviors of solute interstitials. Next, to obtain a correlation that can quantitatively estimate the solute interstitial fraction in the Fe-based alloys, molecular dynamics simulations were conducted to simulate the cascade damage in a series of "artificial" Fe-Cr alloys with tunable binding energies between a substitutional solute (Cr) atom and a Fe self-interstitial atom (SIA). To achieve this, the Fe-Cr cross pair interaction in the interatomic potential was modified by multiplying a scaling factor so that the solute-SIA binding energy varies linearly from positive to negative values. It is found that the solute interstitial fraction has a strong correlation with the solute-SIA binding energy, and the correlation can be approximately described by a Fermi-Dirac-Distribution-like equation. The independent defect production results reported in literature are found to align well with this correlation. The correlation may be used to estimate the solute interstitial fraction in a wide range of Fe-based alloys simply based on the solute-SIA binding energy, without conducting laborious cascade simulations. Furthermore, primary damage was further investigated in Fe-tungsten (W) alloys to investigate the atomic size effect. The large difference in atomic size between Fe and W can introduce both global volume expansion and local lattice distortion in the Fe matrix. In order to understand how oversized W influences the defect production behaviors in Fe-based alloys, molecular dynamics simulations were conducted to study the primary damage in three systems at 300 K: (a) unstrained pure Fe, (b) Fe-5at.%W alloy, and (c) strained pure Fe with the same volume expansion as the Fe-5%W. The investigation of defect production behaviors include the production of Frenkel pairs, and cluster formation preference. Based on the total number of Frenkel pairs, it indicates that the global volume expansion introduced by oversized W and external strain can lead to enhanced defect production. Meanwhile, the defect cluster analysis in all three systems indicates that the local lattice distortion induced by oversized W can significantly influence the morphologies and size distributions of defect structures. Defect formation energies were calculated to interpret the different defect production behaviors in these systems. Finally, radiation can produce not only point defects but also both <100> and ½<111> type dislocation loops in pure Fe and Fe-Cr alloys. However, contradictory experimental results have been reported on how the Cr concentration affects the ratio of <100> to ½<111> dislocation loops. In this section, molecular dynamics simulations were conducted to study how Cr concentration affects the formation probability of <100> dislocation loops from overlapping cascades on a pre-existing ½<111> dislocation loop in a series of Fe-Cr alloys with 0 – 15%Cr at 300 K. Our atomistic modeling directly demonstrates that the ratio of <100> to ½<111> dislocation loops decreases with the increasing Cr concentration, which is consistent with many experimental observations. Next, independent molecular statics calculations show that the formation energies of both <100> and ½<111> dislocation loops increase with the increasing of Cr content. However, the former has a much faster increase rate than the latter, indicating that the formation of <100> loops becomes energetically more and more unfavorable than ½<111> loops as the Cr content increases. The results provide a thermodynamics-based explanation for why Cr suppresses the formation of <100> dislocation loops in Fe-Cr alloys, which can be applied to all <100> loop formation mechanisms proposed in literature. The possible effects of other alloying elements on the formation probability of <100> loops in Fe-based alloys are also discussed. / Doctor of Philosophy / Metallic alloys are important structural and cladding materials for current and future nuclear reactors. The understanding of radiation-induced damage in metallic alloys is important for the safe operation of nuclear reactors. This dissertation mainly focuses on radiation-induced primary damage in iron-based ferritic alloys. Systematic molecular dynamics simulations were conducted to study how different alloying elements influence the primary damage behaviors in iron-based alloys, including defect production behaviors and dislocation loop transformations. The relations between defect production and defect thermodynamics are also studied. First, molecular dynamics simulations were conducted to study the effects of alloying elements on the primary damage behavior in three Fe-based ferritic alloy systems (Fe-Cr, Fe-Cu, and ideal Fe-Cr), with a particular focus on the production behaviors of solute interstitials. It is found that the number ratio of solute interstitials to the total interstitials has distinct behavior in these alloys. In the Fe-Cr alloys, the ratio of Cr interstitials is much higher than the Cr concentration in the Fe-Cr alloys. By contrast, in the Fe-Cu alloys Cu interstitials are barely produced. In the ideal alloy system, the fraction of solute interstitials is close to the solute concentration in the alloys. Among all the factors we have investigated, it is found the relative thermodynamic stability between Fe self-interstitials and solute interstitials plays the most important role on affecting the production behaviors of solute interstitials. Next, to obtain a quantitative correlation that can predict the solute interstitial fraction in the Fe-based alloys, molecular dynamics simulations were conducted to simulate the cascade damage in a series of "artificial" Fe-Cr alloys with tunable binding energies between a substitutional solute (Cr) atom and a Fe self-interstitial atom (SIA). It is found that the solute interstitial fraction has a strong correlation with the solute-SIA binding energy, and the correlation can be approximately described by an analytical equation. The correlation may be used to estimate the solute interstitial fraction in a wide range of Fe-based alloys simply based on the solute-SIA binding energy, without conducting laborious cascade simulations. Furthermore, primary damage was further investigated in iron-tungsten (Fe-W) alloys. W is about 10.5% larger in atomic radius or 34.8% larger in atomic volume than Fe. The oversize W can introduce both global volume expansion and local lattice distortion in the Fe matrix. Through molecular dynamics simulations in a series of model systems for comparison, it is found that oversized W can lead to enhanced defect production. In addition, it is found that oversized W can significantly influence the morphologies and size distributions of defect clusters. Finally, molecular dynamics simulations were conducted to study how Cr concentration affects the formation probability of <100> and ½<111> dislocation loops in a series of Fe-Cr alloys. Our results demonstrate that the ratio of <100> to ½<111> dislocation loops decreases with the increasing Cr concentration, which is consistent with many experimental observations. The formation energies of both <100> and ½<111> dislocation loops indicate that the formation of <100> loops becomes energetically more and more unfavorable than ½<111> loops as the Cr content increases. The results provide a thermodynamics-based explanation for why Cr suppresses the formation of <100> dislocation loops in Fe-Cr alloys.

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Starting with my own travel experiences, and with the help of poets, Elizabeth Bishop, Jorie Graham, and Emily Dickinson, I create a theory of displacement, called Vertigo. Vertigo is not only a sense of falling, but a sense of detachment from reality that I felt traversing through different cultures, languages, and worlds for the first time. Vertigo is a liminal, transformative space that allows an individual to experience the created nature of their own worldview and culture. This is also a physical experience, as Bishop, Graham, and Dickinson give evidence to in their poetry, as the individual experiences a heightened sense of their physical bodies. This work acknowledges the privileged position of the traveler, and reveals that often the observations we make in this privileged position can be moves of colonization. Poetry is one way to both acknowledge these moves, and to also show what we can learn from these moments when we continue to question and explore. Additionally, poetry, as a medium of mindful reflection, allows for a language that is capable of handling the physical knowledge of the body; the mental mapping of the cultural and personal realities of the individual; and also the geographic and political landscapes that surround an individual or population, simultaneously. With this understanding, the theoretical framework for displacement, bodies, and place, which Bishop, Graham, and Dickinson give us, is the foundation for exploring how poetry can provide knowledge for more 'scientific' writing, such as, cultural geography or cognitive science. / Master of Arts

This research examines the correlation between government Ineptitude and the rise of internal displacement as an international phenomenon by using Burma, Colombia and Sudan as models for the crisis, as they are nations deeply affected by inefficient governments and constant civil strife. There ls a very strong parallel between the magnitude of displacement and the rote the government plays in igniting, or preventing, conflict in each respective area. These governments have played an active role In the internal displacement crisis by pursuing, encouraging and supporting policies of forced migrations. Internal displacement, like any other socio-political phenomenon, is a consequence of multiple intricately connected factors, but It Is within domestic governments that the power to constrain or ameliorate the effects of these factors lies, and for this reason they should be looked to when searching for solutions. Analyzing this link can provide a lesson on how the international community should respond to the problem and how reintegration, resettlement and involving local populations in the protection of their own rights, can reduce the crisis.