50 resultados para Visible photocatalyst
Resumo:
In times of globalisation and super-mobility, ideas of normality are in turmoil. In different societies in, across and beyond Europe, we face the challenge of undoing specific notions of normality and creating more inclusive societies with an open culture of learning to live with differences. The scope of
the paper is to introduce some findings on encounters with difference and negotiations of social values in relation to a growing visibility of difference after 1989 in Poland, on the background of a critique of normality/normalisation and normalcy.On the basis of interviews conducted inWarsaw, we investigate how normality/normalisation discourses of visible homosexuality and physical disability are incorporated into individual self-reflections and justifications of prejudices (homophobia and disabilism). More specifically we argue that there are moments of ‘cultural transgressions’ present in everyday practices towards ‘visible’sexual and (dis)ability difference.
Resumo:
In this extended introductory essay, Catherine Gander and Sarah Garland suggest new ways of looking at the correspondences between visual and verbal practices to consider their material and conceptual connections in a specifically American set of histories, contexts and interpretive traditions. Tracing a lineage of experiential philosophy that is grounded in the overturning of a Cartesian mind/body split, the authors argue for pluralistic perspectives on intermedial innovations that situate embodied and imaginative reader-viewer response as vital to the life of the artwork. Gander and Garland chart two main strands to this approach: the pragmatist strain of American aesthetics and social politics, rooted in the essays of transcendentalist Ralph Waldo Emerson and emanating from the writings of John Dewey and William James; and the conceptualist strain of French-American Marcel Duchamp, whose ground-breaking ideas both positioned the artwork as a phenomenological construction and liberated the artist from established methods of practice and discourse. The ‘imagetext’ (after W. J. T. Mitchell) is therefore, argue Gander and Garland, a site consisting of far more than word and image – but a living assemblage of language, idea, thing, cognition, affect and shared experience.
Resumo:
With advancements in the development of visible light responsive catalysts for H2 production frequently being reported, photocatalytic water splitting has become an attractive method as a potential ‘solar fuel generator’. The development of novel photo reactors which can enhance the potential of such catalyst, however, is rarely reported. This is particularly important as many reactor configurations are mass transport limited, which in term limits the efficiency of more effective photocatalysts in larger scale applications. This paper describes the performance of a novel fluidised photo reactor for the production of H2 over two catalysts under UV-Visible light and natural solar illumination. Catalysts Pt-C3N4 and NaTaO3.La were dispersed in the reactor and the rate of H2 was determined by GC-TCD analysis of the gas headspace. The unit was an annular reactor constructed from stainless steel 316 and quartz glass with a propeller located in the base to control fluidisation of powder catalysts. Reactor properties such as propeller rotational speed were found to enhance the photo activity of the system through the elimination of mass transport limitations and increasing light penetration. The optimum conditions for H2 evolution were found to be a propeller rotational speed of 1035 rpm and 144 W of UV-Visible irradiation, which produced a rate of 89 µmol h-1 g-1 over Pt-C3N4. Solar irradiation was provided by the George Ellery Hale Solar Telescope, located at the California Institute of Technology.
Resumo:
The chapter argues that language and cultural communication matter in a transnational world and that the transmission of prejudices against minorities has to be closely analysed while contextualising national histories with minorities. Looking at two spatial sites (Leeds and Warsaw) and analysing interview material that was drawn from a larger study, the authors discuss the way local people address difference particularly through the axes of gendered ethnicity (Muslim men) and gendered class (male underclass). It explores how the same categories of difference are discursively produced in Poland and the UK/ England; to what degree they differ or overlap.
Resumo:
The initial rate of the photocatalysed oxidation of methylene blue, MB, by dissolved oxygen in solution, ri(MB), is measured for a series of titania on glass samples exhibiting a wide range of activities. The samples used include two different types of commercial self-cleaning glass and a lab-made sol-geltitania film. The activities of these samples are also assessed using a resazurin-based photocatalyst activity indicator ink, i.e. Rz paii, for which the initial rates of the photocatalysed reduction of Rz were measured, ri(Rz). A plot of ri(MB)vs. ri(Rz) reveals a goodstraight line, thereby demonstrating a linear correlation (for TiO2films on glass at least) between the slow (usually hours) photocatalysed oxidation of organic materials, such as MB, and the fast (typically minutes) photocatalysed irreversible reduction of a dye, like Rz, in a paii. The possible use of paii technology for assessing, in a simple, quick and inexpensive manner, photocatalytic films both in the laboratory and in situ is discussed briefly.
