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Yes / Thermoplastic polyurethane (TPU)/multi-walled carbon nanotubes (CNT) nanocomposites were prepared by twin-screw extrusion and micro injection molding. The electrical conductivity of micro injection molded polymer nanocomposites exhibits a low value and uneven distribution in the micromolded samples. Real-time tracing of electrical conductivity was conducted to investigate the post thermal treatment on the electrical conductivity of microinjection molded composites. The results show that postmolding thermal treatment leads to a significant increase in the electrical conductivity by over three orders of magnitude for 5 wt % CNT-filled TPU composites. In-situ Transmission electron microscopy confirms the conductive CNT network does not change at the micron/sub-micron scale during thermal treatment. TEM image analysis by a statistical method was used to determine the spatial distribution of CNT in the sample and showed that the average distance between adjacent CNT reduced slightly at the nanometer scale after postmolding thermal treatment. A new conductive mechanism is proposed to explain the enhancement of electrical conductivity after thermal treatment, i.e. micro-contact reconstruction of adjacent CNT in the polymer matrix through annealing-induced relaxation of interfacial residual stress and strain. Raman spectra and small angle X-ray scattering curve of annealed samples provide supporting evidence for the proposed new conductive mechanism. The electron tunneling model was used to understand the effect of inter-particle distance on the conductivity of polymer composites. / Chinese Ministry of Education. Grant Number: 313036; National Natural Science Foundation of China. Grant Number: 51433006

Aromatic polyimides have found widespread applicability which can be partially attributed to their thermal stability, chemical resistance, and high glass transition temperature. However, deficiencies in their processability, solubility, transparency, and relatively high dielectric constants do not always provide the optimum properties for many specialty microelectronics applications. The incorporation of aliphatic segments to form partially aliphatic polyimides, has been used to counteract these shortcomings. Many of the potential uses of partially aliphatic polyimides require them to adhere to ceramic substrates, a main topic of this research. Polyimides and copolyimides that varied in chemical composition by their aliphatic content were characterized by their molecular weight, glass transition temperature, thermal stability, coefficient of thermal expansion, refractive index, dielectric behavior, and mechanical properties. Structure-property relationships were established. The gamma and beta sub-Tg viscoelastic relaxations were investigated to understand their molecular origins. The adhesion performance of a selected series of partially aliphatic polyimides to SiO2/Si was examined using a shaft loaded blister test, which was designed and instrumented for use in a dynamic mechanical analysis instrument. The adhesion was studied at high and low percent relative humidities and for several temperatures to examine if adhesion strength is influenced by polymer chemical composition. The adhesion energy could not be quantified for the entire series of polyimides. It was possible to interpret the quantitative adhesive fracture energies along with the qualitative adhesion strength behaviors, the failure surface analyses, and to offer an understanding of the adhesive chemical structure-physical property relationships. These understandings provide a conclusion that the incorporation of aliphatic segments into the polyimide chemical structure improves the durability of the adhesive bond to SiO2/Si under high percent relative humidities. / Ph. D.

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This research is based upon fieldwork carried out in 2005 and 2006 among Truku people, a Taiwanese indigenous group living in eastern Taiwan. It examines the transformation of the relationship between women and land, and explores meanings related to women’s ownership of land since the government introduced the privatisation of land ownership and cash cropping into Truku society in the 1960s. However, the imposition of these programmes of land reform and capitalisation has generated various types of conflict over land in Truku society. Since the 1960s, Truku people have suffered from loss of lands, arising from various governmental policies on economic development. Hence, many land reclamation movements have arisen, organised by Truku people in order to reclaim their land rights. Furthermore, the transformation of property relations has generated many conflicts over land and inheritance between different households and has created tensions between women and men in terms of land ownership in contemporary society. Most importantly, I reflect on the prevalent idea that women’s right to own land is not sanctioned by ‘traditional’ Truku culture, an argument which, I argue, is problematic, because the idea does not (neatly) fit into actual Truku practices of property transaction. Truku people strategically make use of this narrative of ‘tradition’ in order to strengthen their own tactical position in land disputes which arise between different households. Furthermore, I am critical of the emphasis placed on masculine or male Truku culture in this narrative, which is constructed by Truku activists in land reclamation movements in contemporary Truku society. Through investigation of the processes by which women obtain land in Truku society, I argue that women’s ownership of land cannot simply be regarded as a consequence of the implications of privatisation, but is also a result of kinship practices and their work in cultivating land and maintaining the economic well-being of the household in contemporary society. This research attempts to contribute to anthropological perspectives on property relations, economic anthropology, gender studies, kinship studies and studies of indigenous movements in Taiwan.

Wood fibres can be used as reinforcement in plastics for load carrying purposes. Some advantages compared with conventional man-made fibres are that wood fibres come from a renewable resource, have high specific stiffness and strength, are generally less hazardous to health, biodegradable, and can be manufactured at low cost and high volumes. A clear disadvantage with cellulose-based materials for structural use is their dimensional instability in humid environments. The hygroelastic properties are of high importance in materials development of improved wood-fibre composites. This work deals with the stiffness and hygroexpansion of wood fibres for composite materials. The long-term aim is to design engineered wood fibre composites based on better basic knowledge of wood fibres. Mechanistic models have been used to link the fibrous microstructure with macroscopic composite engineering properties. The properties have been characterized experimentally for various wood-fibre composites and their fibre-mat preforms, by means of curvature measurements at various levels of relative humidity, as well as tensile and compressive tests. From these test results and microstructural characterization, the longitudinal Young’s modulus and transverse coefficient of hygroexpansion of wood fibres were identified by inverse modelling. Some effects of various pulp processes and fibre modifications on the elastic properties of the fibre were observed, illustrating how the mixed experimental-modelling approaches can be used in more efficient materials screening and selection. An improved micromechanical analysis for wood-fibre composites has been presented. The model is more appropriate to combine with laminate analogy, to link fibre properties on the microscale to the macroscopic composite properties and vice versa. It also offers the possibility to include the effects of ultrastructure since it can account for an arbitrary number of phases. An approach to model ultrastructure-fibre property relations has been demonstrated. It includes analytical modelling of multilayered cylindrical fibres as well as finite element modelling of fibres with irregular geometry characterized with microscopy. Both approaches are useful and could be combined with experiments to reveal insights that can pave way for a firmer link between the wood fibre ultrastructure and wood fibre properties. / QC 20100914

This dissertation pursues three overarching themes. The first of these is empirical: to illuminate the actual functioning of the property market in Delhi. After reconstructing the pattern of depression and boom from 1920-40, I argue that these cycles shaped the nature of participation in the market. During the depression of the 1920s many indigenous financial firms came to rely on property rentals and sales. Alongside these, a nascent sector concentrating primarily in real estate came into existence. Compared to planned state intervention, most of Delhi’s urban fabric was created by private construction. Analysis of the state’s relationship to the property market is the second aim of the work. The colonial state both embraced and was constrained by the commodification of land. Though it was the largest landowner in the city, it did not leverage this position. Rather than construction, the state was happier to act on the market indirectly. One means of indirect action concerned forms representations of urban land as commodity. Leases, advertisements and other documents were crucial for its circulation. The strength of the state in the property market derived from its role as enforcer and repository of representations of commodified space. A third aim is to study the forms of struggle engendered by urban property. Struggles over commodification of urban land, when they took collective forms, did not necessarily splinter along class lines. In fact, subsidised housing emerged out of caste, class and nationalist struggles. Conversely, the commodification of land was at issue in struggles that were not ostensibly about property. For instance, this dissertation tracks its salience for understanding communal conflicts over urban shrines. Taken together, the three themes constitute a picture of the city in which forms of capital accumulation – particularly those relating to space – cannot be ignored.

Establishing process-structure-property relationships is an important objective in the paradigm of materials design in order to reduce the time and cost needed to develop new materials. A method to link phase field (process-structure relations) and microstructure-sensitive finite element (structure-property relations) modeling is demonstrated for subsolvus polycrystalline IN100. A three-dimensional (3D) experimental dataset obtained by orientation imaging microscopy performed on serial sections is utilized to calibrate a phase field model and to calculate inputs for a finite element analysis. Simulated annealing of the dataset realized through phase field modeling results in a range of coarsened microstructures with varying grain size distributions that are each input into the finite element model. A rate dependent crystal plasticity constitutive model that captures the first order effects of grain size, precipitate size, and precipitate volume fraction on the mechanical response of IN100 at 650°C is used to simulate stress-strain behavior of the coarsened polycrystals. Model limitations and ideas for future work are discussed.

In his “Letter on Humanism,” Martin Heidegger conveys the importance he attributes to poetry when he states: “Language is the house of being” (“Letter” 239). In response to his early Jesuit education, he developed a secular alternative to theology with his existential phenomenology. Theology, poetry, and phenomenology share the basic concern of explaining the foundations of being. For Heidegger, ownership characterizes being in a fundamental way; in Contributions to Philosophy (From Enowning), he establishes the “Ereignis” (“event of appropriation”) as the foundation of being. Ownership lies at the core of being in his thinking following Being and Time. Yet his philosophy ignores the material circumstances of ownership. By way of a materialist critique of Heidegger’s Idealist phenomenology, I expose how property-relations are encoded in the modern poetry and philosophy of dwelling with the question: who owns the house of being? The answer lies in “self-possession,” which represents historical subjectivity as the struggle for the means of production. Paul Celan, T. S. Eliot, Rainer Maria Rilke, and Paul Valéry are all poets who address the relationship between being and ownership in expressing what Marx and Engels call the “language of real life” in The German Ideology (26). In 1927, Eliot converted to Anglicanism and found solace in the realm of faith; by opting for the theology of dispossession, he surrendered his historical subjectivity. Rilke thought that he could find refuge from the marketplace in aesthetic beauty and pure philosophy but eventually disabused himself of his illusion. Similarly, Valéry sought refuge in the space of thought; basing reality in the mind, he forsook the social realm as the site of contestation for gaining ownership over being. As a poet who distinguished himself from the Idealism of his predecessors, Celan developed a structure of dialogue based upon shared exchange on common ground. A materialist approach to the poetry and philosophy of dwelling exposes property-relations as the foundation of the house of being.

In his “Letter on Humanism,” Martin Heidegger conveys the importance he attributes to poetry when he states: “Language is the house of being” (“Letter” 239). In response to his early Jesuit education, he developed a secular alternative to theology with his existential phenomenology. Theology, poetry, and phenomenology share the basic concern of explaining the foundations of being. For Heidegger, ownership characterizes being in a fundamental way; in Contributions to Philosophy (From Enowning), he establishes the “Ereignis” (“event of appropriation”) as the foundation of being. Ownership lies at the core of being in his thinking following Being and Time. Yet his philosophy ignores the material circumstances of ownership. By way of a materialist critique of Heidegger’s Idealist phenomenology, I expose how property-relations are encoded in the modern poetry and philosophy of dwelling with the question: who owns the house of being? The answer lies in “self-possession,” which represents historical subjectivity as the struggle for the means of production. Paul Celan, T. S. Eliot, Rainer Maria Rilke, and Paul Valéry are all poets who address the relationship between being and ownership in expressing what Marx and Engels call the “language of real life” in The German Ideology (26). In 1927, Eliot converted to Anglicanism and found solace in the realm of faith; by opting for the theology of dispossession, he surrendered his historical subjectivity. Rilke thought that he could find refuge from the marketplace in aesthetic beauty and pure philosophy but eventually disabused himself of his illusion. Similarly, Valéry sought refuge in the space of thought; basing reality in the mind, he forsook the social realm as the site of contestation for gaining ownership over being. As a poet who distinguished himself from the Idealism of his predecessors, Celan developed a structure of dialogue based upon shared exchange on common ground. A materialist approach to the poetry and philosophy of dwelling exposes property-relations as the foundation of the house of being.