O presente trabalho trata da preparação e da caracterização textural e espectroscópica de hidróxidos mistos lamelares de composição [Mg3-xCuxAl(OH)8](CO3)0,5.yH2O (x= 0,3; 0,6; 0,9; 1,2; 1,5; 1,8; 2,1; 2,4; 2,7 e 3,0), bem como do estudo da reatividade desses materiais na hidroxilação do fenol, utilizando peróxido de hidrogênio como oxidante. Os sólidos foram preparados através do método da co-precipitação e caracterizados por difratometria de raios X, análises elementares (C, H, N e metais) e termogravimétricas, medidas de área superficial e, também, pelas seguintes técnicas espectroscópicas: vibracional no infravermelho e espalhamento Raman, eletrônica de absorção no visível-infravermelho próximo e ressonância paramagnética eletrônica. Observou-se que quanto maior o conteúdo de cobre(II) nas amostras, maior é a tendência à formação de CuO. Materiais de coloração azul contendo apenas uma fase cristalina foram obtidos por co-precipitação no intervalo de pH 8-10 e efetuando as etapas de envelhecimento e secagem na temperatura ambiente. Quanto maior a quantidade de íons Cu2+ no hidróxido misto lamelar, menor a cristalinidade e a estabilidade térmica do material. Os espectros de EPR são anisotrópicos (parâmetros g// e g? bem definidos), indicando que os íons cobre(II) se encontram em sítio com simetria axial. À medida que a quantidade de Cu2+ nas amostras aumenta, ocorre uma diminuição no sinal do metal de transição, que pode ser interpretada como decorrência de um acoplamento antiferromagnético entre os íons cobre. Dados de espectroscopia vibracional sugerem que nos hidróxidos mistos há dois tipos de íons carbonato. Além disso, foi observado o fenômeno de abaixamento de simetria dos ânions CO32- ao longo do processo de aquecimento, originando, conforme a temperatura e a composição, materiais de coloração variada. O abaixamento de simetria pode estar sendo ocasionado pela coordenação (ou enxertia) dos íons carbonato aos centros metálicos das lamelas. Os sólidos verdes obtidos por aquecimento possuem, além de bandas no espectro eletrônico atribuídas às transições do tipo d-d (700-800 nm), absorção na região abaixo de 400 nm, que pode ser atribuída à transferência de carga O2- -> Cu2+. Apesar dos difratogramas de raios X apresentarem picos de baixas intensidades referentes às fases espinélio, a coloração ocre observada pode ser devida à presença da fase CuAl2O4 (sólido marrom). Nas amostras cinzas e pretas, os difratogramas de raios X mostram picos intensos atribuídos ao CuO. Os testes de reatividade dos hidróxidos mistos sintetizados na hidroxilação do fenol pelo peróxido de hidrogênio em meio aquoso envolveram a variação de parâmetros reacionais como temperatura, tempo, concentração de substrato e influência de luz, mantendo-se constante a relação molar fenol/Cu2+. O substrato orgânico foi oxidado a catecol, hidroquinona e p-benzoquinona. As substâncias no meio reacional foram quantificadas pela deconvolução do espectro eletrônico da mistura na região do ultravioleta. Como esperado, o material sintetizado sem íons cobre(II) não apresenta atividade catalítica para o sistema reacional estudado. / In this work it was investigated the preparation and spectroscopic characterization of layered hydroxides of composition [Mg3-xCuxAl(OH)8](CO3)0.5.yH2O (x = 0.3; 0.6; 0.9; 1.2; 1.5; 1.8; 2.1; 2.4; 2.7 and 3.0), as well the reactivity of these materials towards phenol hydroxylation, using hydrogen peroxide as oxidizing agent. The solids had been prepared through the co-precipitation method and characterized by X ray diffractometry, elemental analysis (C, H, N and metals), thermogravimetric analysis, surface area measurements, and also by the following spectroscopic techniques: infrared vibrational absortion (FTIR), Raman scattering, vis-NIR electronic absorption and electron paramagnetic resonance (EPR). It was observed that the increase of copper(II) content in the samples favours the CuO formation. Materials of blue coloration containing only one crystalline phase were obtained by the co-precipitation method in the pH range 10 – 8, and were submitted to aging and drying processes at room temperature. As the amount of Cu2+ ions increases in the layered hydroxide material, it was observed a decrease in crystallinity and thermal stability. EPR spectra are anisotropic (parameters g// and g? well defined), indicating that copper(II) ions are in sites with axial symmetry. As the amount of Cu2+ in the samples increases, EPR signal decreases, what can be interpreted as result of an antiferromagnetic coupling between copper ions. FTIR data suggests that the layered hydroxides gave two types of cabornate ions. Moreover, the symmetry lowering phenomena of CO32- anions during the heating process was observed, originating, according to the temperature and sample composition, materials of varied coloration. This lowering of symmetry can be due to coordination (or grafting) of carbonate ions to the metal ions in the layers. Vis-NIR electronic spectra of green solids obtained by heating show absorption in the region below 400 nm, besides bands attributed to d-d transitions (700-800 nm), that can be attributed to O2- -> Cu2+ charge transfer transition. Despite the X ray diffraction peaks of low intensities attributed to spinel phases, the ochre coloration observed can be due to the presence of CuAl2O4 (brown solid). For gray and black samples, X ray diffractograms shows intense peaks attributed to CuO. Reactivity tests about phenol hydroxylation involved the variation of experimental parameters as temperature, time, substrate concentration and influence of light, keeping constant the phenol/Cu2+ molar ratio. The organic substrate was oxidized to cathecol, hydroquinone and p-benzoquinone and these products were quantified by deconvolution of the electronic spectra. As expected, the material synthesized without copper(II) ions does not show catalytic activity for the studied reaction.

abstract: Mixed reality mobile platforms co-locate virtual objects with physical spaces, creating immersive user experiences. To create visual harmony between virtual and physical spaces, the virtual scene must be accurately illuminated with realistic physical lighting. To this end, a system was designed that Generates Light Estimation Across Mixed-reality (GLEAM) devices to continually sense realistic lighting of a physical scene in all directions. GLEAM optionally operate across multiple mobile mixed-reality devices to leverage collaborative multi-viewpoint sensing for improved estimation. The system implements policies that prioritize resolution, coverage, or update interval of the illumination estimation depending on the situational needs of the virtual scene and physical environment. To evaluate the runtime performance and perceptual efficacy of the system, GLEAM was implemented on the Unity 3D Game Engine. The implementation was deployed on Android and iOS devices. On these implementations, GLEAM can prioritize dynamic estimation with update intervals as low as 15 ms or prioritize high spatial quality with update intervals of 200 ms. User studies across 99 participants and 26 scene comparisons reported a preference towards GLEAM over other lighting techniques in 66.67% of the presented augmented scenes and indifference in 12.57% of the scenes. A controlled lighting user study on 18 participants revealed a general preference for policies that strike a balance between resolution and update rate. / Dissertation/Thesis / Masters Thesis Computer Science 2018

acase@tulane.edu / This dissertation research brings together disparate bodies of literature on environmental inequality, sociology of space, and feminist theories of intersectionality to bear on the location and distribution of environmental hazards in the form of landfills. Landfills pose a threat to both ecological sustainability as well as present risks to human health through contamination and pollution. While environmental inequality literatures have executed exceptional work into the dynamics of race and class with respect to the distribution of hazardous waste facilities, the literature is noticeably lacking with respect to identifying relationships between gender and environmental inequalities. Furthermore, many quantitative studies have exclusively focused on hazardous waste facilities as a singular measure of environmental inequality. This study advances the field in three major ways. First, through the inclusion of theorizations based on feminist intersectionality theories, this research empirically analyzes hypotheses derived from intersectionality theories to understand dynamics of gender-environment interactions. Second, this study extends analysis to all forms of waste containment—municipal, industrial, construction and demolition, and hazardous—to identify trends across the social fabric of the contiguous United States at the county level of analysis with respect to multiple forms of environmental hazards. Third, utilizing innovative analytic techniques, this research provides three unique and related strategies, geographic information systems, logistic binary regression, and structural equation modeling, to examine socio-environmental disparities. Findings from each analytic strategy inform the subsequent strategy. Findings suggest the importance of including gender indicators to account for the unique effect of gender and environmental inequality. Furthermore, results indicate the importance in applying intersectionality theories to environmental outcomes as well as empirically testing hypotheses derived from the largely theoretical and qualitatively backed field. Future research should focus on specific regional dynamics of identified socio-environmental interactions by including historical and qualitative data to triangulate quantitative findings. / 1 / Clare Cannon

Abstract not available

This thesis investigates the phenomenon known as a Maori ethnic identity. The topic is investigated using personal interviews and the findings are reported by way of personal narrative. Eight informants were interviewed. All presently identify as Maori and have arrived at this point following a diverse range of experiences. The thesis documents these experiences and those things that are important to them on a personal level. As such, this thesis investigates the topic of Maori ethnicity as it pertains to a group of individuals, not to Maoridom as a whole. It was found that no single paradigm could be applied to my informant�s conception of identity. Each constructed their identity in a unique way. Integral to all identities, however, was the use of both cultural and biological factors. In constructing and maintaining their identities as Maori my informants looked firstly to the presence of ancestry and, following from this cultural practices were employed. The use of ancestry as a basis of identity, and the causal attributes associated with it (such as natural leanings towards the use of Maori language), represent essentialist tendencies on the part of many of my informants. Also of great interest was the perception, by many of my informants, that cultural traits were innate. This is described as a Lamarckian way of viewing ethnicity.

Thesis (Ph. D.)--University of Texas at Austin, 2006. / Vita. Includes bibliographical references.

This study identified some of the ways that multiethnic women describe their ethnic identities, how they perceive ethnic-specific gender identities and what they think are appropriate norms for, and effective outcomes of, communicative behavior. Twelve multiethnic women described their ethnic identity names or labels, and ethnic-specific gender identities; they also recalled a recent situation in which inappropriate ethnic-relevant conversational behaviors occurred. These multiethnic women were found to share an average of nearly six situations in which ethnic identity is most important; the most frequently reported situation being constantly. They significantly differed in respect to the names or labels, and descriptors they used to define and describe their multiethnic identities. The 12 respondents unanimously stated that there are different expectations for women and men within the ethnicities that they identified as components of their multiethnicity. The most frequently cited situation in which it is most important for them to intensify their gender identity is during celebratory occasions and at home or with family. 10 of the total 12 respondents perceive that their gender identity is shared by a large number of other people. Recently recalled conversations indicate that work and employment-related individuals specifically discussing ethnicity, most frequently used inappropriate communicative behaviors. The most frequently reported situation in which they intensify their multiethnic identities is while being with other ethnic ingroup members, though 75% of them indicated that their particular definition of their ethnic identity was shared by only a small number of other people. Nearly 70% responded that they very often--on a daily or weekly basis--experience others' violation of rules for competent communication. The most frequently cited recommendations they made for others to be more competent communicators were: 1) get informed/take some ethnicity classes, and don't be so harsh; 2) give individuals credit for being unique and diverse; 3) be polite/respectful; 4) recognize and refrain from stereotyping; 5) don't be prejudiced and change feelings/perceptions about ethnicized individuals & groups; 6) don't assume, approach individuals directly and don't discriminate. / Graduation date: 1994

The study is based on a programme of research into functionintegrated city environments. In-depth case studies have beencarried out on two planning projects in Karlstad andVästerås. The object of these case studies wasexplorative, the intention being to develop a clear idea of theconditions for function integration and how these aremanifested in detailed planning processes. The key concepts of the study pertain to both the localenvironment and the process of detailed planning. Functionintegration is defined as an action within planning. The resultof detailed planning is a physical environment. What theplanning process aims to produce is a function integratedenvironment. The object of study is function integration in theprocess of detailed planning. A function integrated environment needs to be experienced assuch from eye-level. From this perspective it should bepossible to distinguish the following elements in physicalspace in the local environment: residential housing, places ofwork and services, public space with attractive places, publicland which is structured to give the pedestrian a sense ofcontinuity and connection with surrounding areas. The starting-point here is that a function integratedenvironment is one of many local environments. It is a type ofenvironment for which there is ample justification for goodplanning. The contribution of this study to the city planningdebate is primarily empirical. It investigates experiences ofdetailed planning, and conclusions that may be drawn. Onecomprehensive thesis is that in practice, there is a tendencyin detailed planning to separate functions. This is part of theexplanation why planning projects that aim to produce functionintegrated environments can seem overly complex, demanding manyresources. Keywords:Mixed use, detaild development plan, function,integration.

Due to the introduction of Restriction of Hazardous Substances (RoHS) directive Pb containing solders have been banned from the electronics industry and a reliable replacement for the Sn-Pb solder is being sought for by industry around the globe. Medical and Defense industries are currently exempt from the directive and use Sn-Pb solder in their manufacturing process. The switch to lead-free has led component manufacturers to use different lead-free solders, thus causing mixed solder joints of lead-free components with Sn-Pb paste. In this study, mixed assembly microstructures and mechanical properties were examined. Furthermore, six novel lead-free solders were prepared using SAC105 solder doped with elements: Ti, Ni, Mn, La, Ce and Y. The solidification microstructures, fracture behavior and wetting properties of these solders were evaluated to find a suitable replacement for SAC105 solder.

Due to the introduction of Restriction of Hazardous Substances (RoHS) directive Pb containing solders have been banned from the electronics industry and a reliable replacement for the Sn-Pb solder is being sought for by industry around the globe. Medical and Defense industries are currently exempt from the directive and use Sn-Pb solder in their manufacturing process. The switch to lead-free has led component manufacturers to use different lead-free solders, thus causing mixed solder joints of lead-free components with Sn-Pb paste. In this study, mixed assembly microstructures and mechanical properties were examined. Furthermore, six novel lead-free solders were prepared using SAC105 solder doped with elements: Ti, Ni, Mn, La, Ce and Y. The solidification microstructures, fracture behavior and wetting properties of these solders were evaluated to find a suitable replacement for SAC105 solder.