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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.
111

Solar city :

Nadyrshine, Lilia Erica January 2001 (has links)
This research examines the problem of urban open space design in the city with an increasing ultraviolet radiation (UVR) and covers aspects of behaviour scenarios, built sunshade design and choice of sunshade plants for landscaping / Thesis (PhDArchitectureandDesign)--University of South Australia, 2001
112

Studying polymer degradation at a molecular level via soft ionisation mass spectrometry

Bennet, Francesca, Chemical Sciences & Engineering, Faculty of Engineering, UNSW January 2009 (has links)
The present study employs a range of soft-ionisation mass spectrometry techniques to study the degradation of model compounds of poly(methyl methacrylate), poly(n-butyl acrylate) and poly(2-hydroxyethyl methacrylate) under conditions designed to simulate the worst-case scenario that would be experienced by a polymer used in a surface coating on a steel roof. Vinyl-terminated and saturated polymers were degraded for periods of up to 2 years under simulated solar radiation at a temperature of 95??C, temperature of 95 ??C in the dark, and simulated solar radiation at 35??C. Similar degradation mechanisms were observed under heat and UV radiation. The presence of UV radiation accelerated the degradation occurring at high temperature, and vice versa. The combination of heat and UV radiation is far more detrimental to the polymers than either of these conditions alone. Both vinyl-terminated and saturated pMMA degraded under UV radiation at 95??C, whereas under conditions of UV radiation alone or high temperature alone, the saturated polymer was found to be stable. The vinyl-terminated pMMA degrades in all cases via the formation of ethylene oXide-type end groups, which subsequently rearrange under the expulsion of formaldehyde and 2-oxo-propionic acid methyl ester. This is in contrast to all previous literature, in which pMMA degrades via depolymerisation and is stable at 95??C. Degradation of pBA included a degradation mechanism similar to that of pMMA in addition to other polymer fragments, some of which cannot be assigned. pBA (both saturated and vinyl-terminated) showed a tendency to crosslink under all degradation conditions in this study. Only saturated pHEMA was stable under thermal degradation. In all other cases, pHEMA showed some degradation, but displayed a much greater tendency to crosslink rapidly. Terminal vinyl bonds were shown in all cases to be a weak point in the polymer with respect to degradation. pMMA was found to be the least reactive of these polymers. pHEMA showed some small degradation but had a greater tendency to crosslink via the hydroxyethyl side groups. pBA does not have any such reactive groups, and its crosslinking reaction may be explained via the acrylate backbone, or the longer alkyl ester group.
113

Atmospheric oxygen density studies by solar ultra-violet absorption

Gough, Paul Lancelot January 1971 (has links)
ix, 146 leaves : ill. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Thesis (Ph.D.1972)--University of Adelaide, Dept. of Physics, 1972
114

Satellite and rocket measurements of solar ultraviolet flux and atmospheric molecular oxygen density

Lockey, George William Albert January 1972 (has links)
viii, 166 leaves : ill. ; 27 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Thesis (Ph.D.)--University of Adelaide, Dept. of Physics, 1973
115

Solar city :

Nadyrshine, Lilia Erica January 2001 (has links)
This research examines the problem of urban open space design in the city with an increasing ultraviolet radiation (UVR) and covers aspects of behaviour scenarios, built sunshade design and choice of sunshade plants for landscaping / Thesis (PhDArchitectureandDesign)--University of South Australia, 2001
116

Solar city :

Nadyrshine, Lilia Erica January 2001 (has links)
This research examines the problem of urban open space design in the city with an increasing ultraviolet radiation (UVR) and covers aspects of behaviour scenarios, built sunshade design and choice of sunshade plants for landscaping / Thesis (PhDArchitectureandDesign)--University of South Australia, 2001
117

Photoaging of skin a functional genomics approach /

Urschitz, Johann G. E. January 2004 (has links)
Thesis (Ph. D.)--University of Hawaii at Manoa, 2004. / Includes bibliographical references (leaves 198-219).
118

Solar radiation processes on the East Antarctic Plateau : interaction of clouds, snow, and atmospheric gases /

Hudson, Stephen R. January 2007 (has links)
Thesis (Ph. D.)--University of Washington, 2007. / Vita. Includes bibliographical references (p. 85-88).
119

Validation of a sun-exposure questionnaire for adolescent girls /

Cobb, Jennifer L., January 2001 (has links) (PDF)
Thesis (M.S.) in Food Science and Human Nutrition--University of Maine, 2001. / Includes vita. Includes bibliographical references (leaves 55-59).
120

Estimativa da irradiação total sobre uma superfície inclinada a partir da irradiação global na horizontal /

Scolar, José, 1947- January 2003 (has links)
Orientador: Dinival Martins / Resumo: Neste trabalho, realizou-se um estudo de modelagem da irradiação total que incide sobre uma superfície inclinada, com face voltada para o Equador, e com inclinação de 22,85º, igual a da latitude local. Foram testados 7 modelos, existentes na literatura, utilizando partição diária de energia. Os modelos de Temps & Coulson, Klucher e circunsolar, apresentam os piores desempenhos e não devem ser utilizados na estimativa da irradiação total diária em Botucatu, por outro lado os modelos de Liu & Jordan, Hay, Perez et al. e Reindl et al., são similares entre si, e apresentam boa concordância quando comparados com os dados observacionais, sendo o modelo de Hay ligeiramente superior aos outros. O propósito deste trabalho é obter um modelo que utilize somente a irradiação global medida na superfície horizontal para estimar a irradiação total na superfície inclinada. Para tanto, os modelos de estimativa foram modificados de duas maneiras diferentes. Na primeira, a irradiação difusa foi estimada em função da irradiação global, através do ajuste empírico utilizando a técnica de regressão linear, na forma Kd = f (Kt) , fração da difusa contida na global (Kd ), com o índice de claridade (Kt ), nesse caso, o melhor ajuste é dado por um polinômio de 4º grau Kd = 0,993 + 0,178Kt - 0,945Kt2 - 4,712Kt3 + 4,891Kt4 . Na Segunda modificação, a irradiação direta KBH , fração da irradiação direta contida na irradiação global, foi ajustada através da técnica de regressão linear, em função do índice de claridade, na forma KBH = f (Kt ) , nesse caso o melhor ajuste foi linear, obtido para intervalos específicos de Kt , KBH = 0 para Kt £ 0,25 , e KBH = -0,386 +1,572Kt para Kt >0,25. Os resultados obtidos com essas modificações mostram que os modelos têm melhores... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: A modelling study of the total irradiation reaching a tilted surface facing towards the equator at tilt same of local latitude of 22,85º,, is presented. In this study seven total irradiation incident on a tilted surface estimate models were tested and compared among them, using the daily partitioning energy. Temps & Coulson, Klucher and circumsolar models showed very poor results, and it is suggested that they should not be used to estimate the daily total irradiation for the Botucatu region. On the other hand the Liu & Jordan, Hay, Perez et al. and Reindl et al. models have shown similar performance and presented a good agreement with the observational data. The Hay model however produced better irradiation estimates. The aim of this study is examine and improved irradiation estimative model for tilted surface knowing only the global irradiation measured at horizontal surface. In order to achieve this, two modifications were made on those models mentioned above. The first modification consisted to apply empirical functions to determine the diffuse irradiation by the global radiation measurements. These empirical functions were tuned using the regression linear thecnique, the fraction of the diffuse irradiation (Kd ) from the global irradiation, was correlationed with the clearness index (Kt ). In this case the highest correlation found was, Kd = 0,993 + 0,178Kt - 0,945Kt2 - 4,712Kt3 + 4,891Kt4 a fourth order polynomial function. In the second modification the fraction of the direct irradiation KBH from the global irradiation was correlationed assuming a linear correlation at given intervals of Kt : KBH = 0 for Kt £ 0,25 , and KBH = -0,386 + 1,572Kt for Kt >0,25 otherwise. Model results showed the empirical relationship KBH = f (Kt ) , present better results and the Hay model presented a better performance compared with others models for the... (Complete abstract, click electronic address below) / Doutor

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