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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
321

Writing to Reach You: The Consumer Music Press and Music Journalism in the UK and Australia

Brennan, Marc Andrew January 2005 (has links)
The music press and music journalism are rarely subjected to substantial academic investigation. Analysis of journalism often focuses on the production of news across various platforms to understand the nature of politics and public debate in the contemporary era. But it is not possible, nor is it necessary, to analyse all emerging forms of journalism in the same way for they usually serve quite different purposes. Music journalism, for example, offers consumer guidance based on the creation and maintenance of a relationship between reader and writer. By focusing on the changing aspects of this relationship, an analysis of music journalism gives us an understanding of the changing nature of media production, media texts and media readerships. Music journalism is dialogue. It is a dialogue produced within particular critical frameworks that speak to different readers of the music press in different ways. These frameworks are continually evolving and reflect the broader social trajectory in which music journalism operates. Importantly, the evolving nature of music journalism reveals much about the changing consumption of popular music. Different types of consumers respond to different types of guidance that employ a variety of critical approaches. This thesis, therefore, argues that the production of music journalism is one that is influenced by the practices of consumption.
322

The problematic of video art in the museum (1968-1990)

Manasseh, Cyrus January 2008 (has links)
This thesis discusses how museum structures were redefined over a twenty-two year period in specific relation to the impetus of Video Art. It contends that Video Art would be instrumental in the evolution of the contemporary art museum. The thesis will analyse, discuss and evaluate the problematic nature and form of Video Art within four major contemporary art museums - the Museum of Modern Art (MoMA) in New York, the Georges Pompidou National Centre of Art and Culture in Paris, the Tate Gallery in London and the Art Gallery of New South Wales (AGNSW) in Sydney. By addressing some of the problems that Video Art would present to those museums under discussion, the thesis will reveal how Video Art would challenge institutional structures and demand more flexible viewing environments. As a result, the modern museum would need to constantly modify their policies and internal spaces in order to cope with the dynamism of Video Art. This thesis first defines the classical museum structure established by the Louvre during the 19th century. It examines the transformation from the classical to the modern model through the initiatives of the New York Metropolitan Museum to MoMA in New York. MoMA would be the first major museum to exhibit Video Art in a concerted fashion and this would establish a pattern of acquisition and exhibition that became influential for other global institutions to replicate. MoMA's exhibition and acquisition activities are analysed and contrasted with the Centre Pompidou, the Tate Gallery and the AGNSW in order to define a lineage of development in relation to Video Art. This thesis provides an historical explanation for the museum/gallery's relationship to Video Art from its emergence in the gallery to the beginnings of its acceptance as a global art phenomenon. Curatorial strategies, the influx of corporate patronage and the reconstruction of spectatorship within the gallery are analysed in relation to the unique problematic of Video Art. Several prominent video artists are examined in relation to the challenges they would present to the institutionalised framework of the modern art museum and the discursive field surrounding their practice. In addition, the thesis contains a theoretical discussion of the problems related to Video Art imagery with the period of High Modernism; examines the patterns of acquisition and exhibition, and presents an analysis of global exchange between four distinct contemporary art institutions.
323

Promulgating graduate research and disseminating student information through web applications and database management

Chien, Li-ching, Chang, Kai-Hsiung. January 2006 (has links) (PDF)
Thesis(M.S.)--Auburn University, 2006. / Abstract. Vita. Includes bibliographic references (p.79-81).
324

Development and Characterization of Novel Nanofibrous Metal–Organic Framework Adsorption Membranes for Water Treatment

Efome, Johnson Effoe 05 October 2018 (has links)
Membrane technology has become a predominant process in providing one of the key components of life (water), either through water and wastewater treatment for water quality purposes or desalination as seen in Ultra-filtration, Nano-filtration, Reverse osmosis, Membrane distillation, Pervaporation, among others. With the ever-increasing demand for portable water due to population increase, constant research has focused on the improvements of the performances of the different water treatment systems including enhancing the performance of the membrane. Among all the different membrane performance enhancement techniques exploited, incorporation of filler has gained much grounds in the last decades. Traditional fillers like silica gel, activated carbon, metal oxides and zeolites are now being challenged by the recent class of mesoporous materials known as Metal Organic Frameworks (MOFs), which are built of metal ions or metal ion clusters linked together by organic ligands giving these materials tunable pore geometries and pore volume, greatly improved surface area with extraordinary adsorptive properties. The membrane incorporating MOFs demonstrate enhance performances more than the other fillers due to the good coordination of the organic moiety and polymers. The overall objective of this project is to develop and study a membrane incorporated MOFs nanofiber system vis-à-vis their applications in heavy metal contaminated water treatment, stability in aqueous media and the advantages and drawbacks of these composite membranes with regards to the quality of the water produced. The developed materials were characterized by SEM, FTIR, TEM, XPS, DSC, and TGA. The heavy metals earmarked for this study include; Lead, Mercury, Cadmium, and Zinc and were studied using flame atomic absorption spectrometry (FAAS). Upon successful fabrication of the nanofiber membranes, detailed adsorption studies were conducted (pristine MOF, pristine nanofibers, enmeshed MOFs) to establish adsorption kinetics and isotherm, which were used further to select the best performing membranes for filtration application. Two different MOFs were used, MOF808; made of Zirconium and Benzene Tricarboxylate) and MOF F300; made of Iron and Benzene Tricarboxylate) The adsorption capacities of the MOFs for the different heavy metal analyzed were; MOF 808 (Pb-170.74 mg g-1, Zn-287 mg g-1, Cd-225.05 mg g-1, Hg-276.96 mg g-1) and MOF F300 (Pb-148.13 mg g-1, Hg-229.66 mg g-1), while the membrane adsorption capacities were; PA808 (MOF 808 embedded within polyacrylonitrile (PA) nanofibers, (Pb-23.98 mg g-1, Hg-50.88 mg g-1), PA300, MOF F300 embedded within polyacrylonitrile nanofibers, (Pb-30.19 mg g-1, Hg-53.09 mg g-1). Upon activation of MOF 808 by water (hydractivation), the removal efficiency of MOF 808 was improved by 10% while the MOF membrane efficiency was increased by 30%. Filtration experiments could produce 577.5 L of treated water with a single layer of PAN/ MOF808 membrane at 0.1 bar using a 50 ppb Pb ion feed solution.
325

Strategic immobilisation of catalytic metal nanoparticles in metal-organic frameworks

Anderson, Amanda E. January 2017 (has links)
This thesis describes the synthesis, characterisation and catalytic testing of multifunctional immobilised metal nanoparticle in metal-organic framework (MOF) materials. Combining the activity of metal nanoparticles with the porosity and Lewis acidity of metal-organic frameworks provides a single catalytic material which can perform multi-step reactions. Strategies to immobilise the metal nanoparticles within the metal-organic frameworks have been investigated. Immobilisation has been achieved by applying three different methodologies. First, deposition of metal nanoparticle precursors within mesoporous MOFs is discussed. Chapter 3 shows the effectivity of the double solvents deposition technique to achieve dispersed and small nanoparticles of around 2.7 nm. The best system combined Pd nanoparticles with MIL-101(Cr). This system was further investigated in tandem reductive amination catalysis, discussed in Chapter 4, to investigate the activity and selectivity provided by these multifunctional catalysts. Another immobilisation technique was performed by coating Pd decorated SiO2 spheres with a MOF layer. Using this technique, MOF was grown cyclically in solution, providing tuneable shell thicknesses of MOF on the metal nanoparticle decorated oxide spheres. While the homogeneity of the MOF shell needs more optimisation, it was determined that the surface charge on the spheres played an important role in the growth of MOF in the desired location. Finally, the third immobilisation technique is the core-shell growth of MOF on colloidal metal nanoparticles. Polymer-capped metal nanoparticles with well-defined shapes were synthesised and characterised. From here, the optimisation of conditions for core-shell growth of UiO-66 and MIL-100(Sc) were investigated. Conditions which provided the desired core-shell morphology were found for both MOF types. These materials were then subsequently used in tandem reductive amination catalysis and a more straightforward styrene hydrogenation. It was shown that the metal nanoparticles remain active catalysts within either MOF shell and the MOF shell stabilises the metal nanoparticle and acts as a Lewis acid catalyst.
326

Actinide hydrocarbyl chemistry supported by a small flexible pyrrolic macrocycle

Suvova, Marketa January 2018 (has links)
Thorium(IV) and uranium(IV) coordination complexes have been studied for the last 60 years. They have shown interesting reactivity that is often divergent from that of transition metal complexes, and that also provides an insight into some unanticipated differences between thorium(IV) and uranium(IV). An introduction to thorium(IV) and uranium(IV) organometallic chemistry supported by carbocyclic and N-donor ligands is given in Chapter One. The reactivity of actinide alkyl, amide and alkynyl complexes towards small molecules is discussed and select examples provided. The redox chemistry of thorium and uranium is also introduced. Chapter Two describes the alkylation and amination chemistry of uranium(IV) and thorium(IV) trans-calix[2]benzene[2]pyrrolide ((L)2-) complexes, [(L)AnCl2], yielding new actinide(IV) complexes of the type [M(L-2H)An(R)] (M = Li or K, R = Me, CH2SiMe3, CH2Ph, N(SiMe3)2), where (L)2- undergoes further deprotonation to (L-2H)4-. Additionally, the lability of the [M(L-2H)An(R)] “ate”-complexes towards M+ ion exchange is addressed. Further, the selective ligand reprotonation of (L-2H)4- to (L)2- using HSiR'3 (R' = Me, iPr) and [Et3NH][BPh4] yielding [(L)An(C≡CSiR'3)2] and [(L)An(R)][BPh4] respectively, is explained. The reactivity of these complexes towards amines, silanes, alkenes, tin hydrides, silicone grease, tBuNC, H2, CO, CO2 or CS2 is described. Crystallographic characterisation shows that [(L)Th(N(SiMe3)2)][BPh4] contains an unusual example of a thorium(IV) bis-arene coordination mode. The reactivity of [(L)Th(C≡CSiMe3)2] towards a number of substrates including alkenes, [Ni(COD)2], [Pt(norbornene)3], P4, CO2 or H2 is also discussed. Activation of CO2 by [(L)Th(C≡CSiMe3)2] at 80 °C results in (L)2- functionalisation and abstraction to yield a new tricyclic organic molecule with the general formula LCO. The addition of [Ni(COD)2] to [(L)Th(C≡CSiMe3)2] and PR''3 (R'' = phenyl, cyclohexyl) yields heterobimetallic complexes [(L)Th(C≡CSiMe3)2·Ni(PR''3)]; these products display both dipyrrolic and bis-arene coordination. The changes in ligand coordination mode are discussed alongside DFT computational analyses that have been carried out by collaborators. The substitution reactions of [(L)AnCl2] with NaBH4 to form actinide(IV) borohydride complexes [(L)An(BH4)2] and subsequent attempted abstractions of BH3 from [(L)Th(BH4)2] are presented. Conclusions are provided at the end of the chapter. Chapter Three focusses on the oxidation chemistry of uranium(IV) within the (L)2- and (L-2H)4- ligand framework, prompted by the isolation of a uranium(V) complex [Li[(L)UO2]·LiI] from the oxidation of the uranium(IV) complex [Li(L-2H)U(Me)]. Conclusions are provided at the end of the chapter. Experimental methods and characterising data are given in Chapter Four.
327

Challenges of public participation in the implementation of portable toilets in South Africa: A case study of Makhaza area in Cape Town, Western Cape Province (2011-2015)

Bob, Thandile January 2018 (has links)
Magister Administrationis - MAdmin / This research critically sought to conduct a study, to find out whether there was public participation prior to the installation of portable flush toilets (porta potties) in Makhaza Area, Khayelitsha, during 2011-2015. A discussion of a theoretical framework on public participation and decision making forms the basis upon which this study is grounded. The study proceeded to explore public participation in public policy in the local South African context with a specific focus on the legislative environment. To gather information, a maximum number of 30 households in the area of study were interviewed using the technique of purposive sampling falling under non-probability sampling. The selected participants have a distinct connection with the phenomenon under research, and adequate and significant living knowledge of public participation, but have not participated in the process of public participation. Furthermore, both qualitative and quantitative approaches were followed in order to enrich the study deeply.
328

Proposta de um framework baseado em arquitetura orientada a serviços para a robótica

Guimarães Júnior, Carlos Solon Soares January 2015 (has links)
Sistemas embarcados, em especial aqueles utilizados em robótica, apresentam, em sua estrutura, uma multiplicidade de dispositivos que resultam em uma arquitetura bastante heterogênea e bem distribuída. Para auxiliar na resolução dessa complexidade inerente, este trabalho resgata os conceitos de frameworks, buscando na sua integração e modelo conceitual, desenvolver um conjunto de ferramentas que gerencia a mediação entre sistemas embarcados e demais aplicações de software, fornecendo bibliotecas e componentes reutilizáveis para aplicações na robótica. Propõe-se utilizar framework e middleware de sistemas open-source para integração entre a plataforma de software e hardware. Um dos objetivos do projeto é criar um framework multi-plataforma com diferentes tipos de serviços para o de desenvolvimento de aplicações no campo da robótica. O projeto tem como estudo de caso sistemas embarcados aplicados em robótica móvel e tecnologia assistiva. / Embedded systems, especially those used in robotics, present in its structure, a plurality of devices that result in a very heterogeneous and well distributed architecture. To help resolve this inherent complexity, the work rescues the concepts of frameworks, seeking their integration and conceptual model, develop a set of tools that manage to mediate between embedded systems and other of software applications, providing reusable libraries and components for applications in robotics. It is proposed to use framework and middleware systems open source for integration between the platform software and hardware. One of the project objectives is to create a multi-platform framework with different types of services, considering the programming and compatibility with hardware for the development of applications in the field of robotics. The project’s case study developing embedded applied in mobile and Assistive Technology robotics.
329

Defining the architecture and attributes of successful climate change adaptation surrounding long-lived infrastructure in the coastal zone

Armstrong, Jennifer C. January 2017 (has links)
Climate variability and change threaten human and physical systems in coastal zones. With more than 10% of the global population now living and working in low elevation coastal zones, successful adaptation to climate change is becoming a pressing issue, particularly for areas featuring critical, long-lived infrastructure. The aim of this research is to define the architecture and attributes contributing to successful adaptation to climate change. Here, success is measured in terms of the process rather than outcomes of adaptation initiatives. The research features two empirical phases: adaptation framework analysis and an evaluation of factors affecting the adaptive capacity of stakeholder organisations. Framework analysis involved the development of a criterion tool based on recurrent features of different adaptation frameworks as described in research literature. Six hallmarks emerged as discriminators of Scenario-Led (SL), Vulnerability-Led (VL) and Decision-Centric (DC) frameworks. The criterion tool was then tested using four UK coastal case study areas, drawing on evidence from public domain adaptation documents. The Grounded Theory Methodology (GTM) was used investigate factors enabling or inhibiting stakeholder adaptation efforts by designing and iteratively adjust semi-structured interviews with stakeholder organisations in the Sizewell nuclear neighbourhood, Suffolk, UK. The findings from the two phases were brought together to identify opportunities to improve the adaptation processes. Analysis of the adaptation architecture revealed that stakeholders rarely use one theoretical adaptation approach. A hybrid adaptation framework is adopted, with the DC/SL or DC/VL being utilised most frequently. Findings reveal a mismatch between theoretical frameworks and those implemented in practise. Semi-structured interviews exposed six key themes defining adaptation process. Stakeholder organisations reported 12 factors that affect their standpoints on each key theme. Standpoints were broadly consistent between similar stakeholder organisations. Stakeholder groups, key themes and influencing factors provide an evidence base for evaluating the complex social dynamics affecting successes of the adaptation process, offering a route to pragmatic adaptation guidance. By considering the architecture and attributes of adaptation coastal stakeholders in neighbourhoods with long-lived infrastructure could strengthen the adaptation process, thereby realising their shared vision(s) of integrated coastal management. There is scope for improving and advancing the research. It is acknowledged that the inventories of adaptation initiatives were uneven in size and scope, potentially limiting the evaluation of the criterion tool. This may be addressed by assessing other coastal neighbourhoods with long-lived infrastructure. When interviewing representatives from stakeholder organisations, it was difficult to differentiate between personal or professional views. Future research could investigate how the role of the individual influences adaptation efforts. Insights could further refine the architecture and attributes of adaptation.
330

Characterization Of Nanoporous Materials Using Gas Adsorption Isotherms: Evaluating Their Potential For Gas Storage And Separation Applications

Krungleviciute, Vaiva 01 January 2009 (has links)
In order to find/design porous materials that could be used in practical applications involving adsorption, it is important to investigate the basic properties (i.e. isosteric heat, specific surface area, binding energy, pore size, pore volume, etc.) of each material. With this aim in mind we have looked at three different types of materials: single-walled carbon nanotubes (prepared by the HiPco and laser methods), single-walled nanohorns (dahlia-like and bud-like) and metal-organic frameworks (Cu-BTC and RPM-1). For these substrates we have measured volumetric adsorption isotherms using several gases such as neon, argon, tetrafluoromethane (CF4), xenon, and methane (not all gases for all substrates). Experimental adsorption isotherms were measured using methane, argon, xenon, and neon gases on unpurified single-walled carbon nanotubes prepared by the HiPco method. The main idea behind these experiments was to investigate, using different size gas molecules, the sites available for adsorption on this type of porous material. We found that surface area occupied by these adsorbates on the sample is the same, regardless of their size. This means that all the gases have access to the same group of adsorption sites. Since the biggest adsorbate in this experiment was Xe, and since it is unlikely that it could penetrate the interstitial channels in the nanotube bundles, we conclude that none of the gases, including the smallest one - Ne, are able to adsorb in the interstitial channels in bundles of single-walled carbon nanotubes. For the case of argon on laser produced single-walled carbon nanotubes we measured 21 adsorption isotherms using argon gas temperatures between 40 and 153 K that were used to determine the isosteric heat of adsorption for this system. Our experimental results were compared to the ones from computer simulations performed by J. K. Johnson (from the University of Pittsburgh) for the same gas on heterogeneous and homogenous bundles. It was observed that the isosteric heat data matches better with data computed for heterogeneous nanotube bundles. This indicates that at the lowest pressure and coverages argon might be adsorbing in the defect-induced interstitial channels. We studied Cu3(Benzene-1,3,5-tricarboxylate)2(H2O)3 (abbreviated as Cu-BTC) metal-organic framework with argon to determine the sites available for adsorption on this material. Volumetric adsorption isotherms were measured at temperatures between 66 and 143 K. We found two substeps in the isotherm data, indicating that there are two types of pores present in the material: tetrahedrally-shaped side pockets and the main channels. Our experimental results were compared with data from simulations conducted using the Grand Canonical Monte Carlo method. We determined that the theoretical results match reasonably well with ours if the coverage is scaled down by a factor of 1.6. We explored the potential of two different metal-organic framework materials (Cu-BTC and RPM-1) for gas separation application. We used argon and tetrafluoromethane (CF4) gases to check if this can be achieved through kinetic and steric mechanisms. We found that Cu-BTC has excellent potential in gas separation using a steric mechanism, since argon easily adsorbs into the small pores present in the sample, while CF4 is excluded from them. Adsorption properties of RPM-1 showed that it could be employed in gas separation using a kinetic mechanism - argon gas adsorbs and reaches equilibrium in the pores of the sample more than the order of magnitude faster than CF4. Closed-ended dahlia-like nanohorns were studied with neon and tetrafluoromethane gases. In the first layer of neon and tetrafluoromethane adsorbed on dahlia-like nanohorns we found two substeps. These results were compared with results of computer simulations performed by Prof. M. Calbi. We determined, after comparison with the simulation isotherms, that the lower pressure substeps correspond to adsorption of Ne and CF4 in the narrowest parts of interstitial channels of the aggregates. Surface area calculated from neon isotherms was found to be higher than the one obtained using CF4, meaning that the smaller Ne molecule has the access to the parts of the interstitial channels that are not accessible for the bigger CF4 molecule. Features that appeared in neon adsorption isotherms on bud-like nanohorn aggregates were quite different from the ones on dahlia-like aggregates. We measured neon adsorption isotherms on this type of sample at temperatures between 22 and 49 K. In the monolayer regime we observed one single substep whose origin we can not definitely identify, because the structure of the bud-like nanohorns is not well-known. The binding energy value that was calculated from the isotherm data was lower than the value for neon adsorbed in the grooves of nanotube bundles but higher than for neon on graphite.

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