921 resultados para Palace of Fine Arts (Chicago, Ill.)


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This work investigates the computer modelling of the photochemical formation of smog products such as ozone and aerosol, in a system containing toluene, NOx and water vapour. In particular, the problem of modelling this process in the Commonwealth Scientific and Industrial Research Organization (CSIRO) smog chambers, which utilize outdoor exposure, is addressed. The primary requirement for such modelling is a knowledge of the photolytic rate coefficients. Photolytic rate coefficients of species other than N02 are often related to JNo2 (rate coefficient for the photolysis ofN02) by a simple factor, but for outdoor chambers, this method is prone to error as the diurnal profiles may not be similar in shape. Three methods for the calculation of diurnal JNo2 are investigated. The most suitable method for incorporation into a general model, is found to be one which determines the photolytic rate coefficients for N02, as well as several other species, from actinic flux, absorption cross section and quantum yields. A computer model was developed, based on this method, to calculate in-chamber photolysis rate coefficients for the CSIRO smog chambers, in which ex-chamber rate coefficients are adjusted by accounting for variation in light intensity by transmittance through the Teflon walls, albedo from the chamber floor and radiation attenuation due to clouds. The photochemical formation of secondary aerosol is investigated in a series of toluene-NOx experiments, which were performed in the CSIRO smog chambers. Three stages of aerosol formation, in plots of total particulate volume versus time, are identified: a delay period in which no significant mass of aerosol is formed, a regime of rapid aerosol formation (regime 1) and a second regime of slowed aerosol formation (regime 2). Two models are presented which were developed from the experimental data. One model is empirically based on observations of discrete stages of aerosol formation and readily allows aerosol growth profiles to be calculated. The second model is based on an adaptation of published toluene photooxidation mechanisms and provides some chemical information about the oxidation products. Both models compare favorably against the experimental data. The gross effects of precursor concentrations (toluene, NOx and H20) and ambient conditions (temperature, photolysis rate) on the formation of secondary aerosol are also investigated, primarily using the mechanism model. An increase in [NOx]o results in increased delay time, rate of aerosol formation in regime 1 and volume of aerosol formed in regime 1. This is due to increased formation of dinitrocresol and furanone products. An increase in toluene results in a decrease in the delay time and an increase in the rate of aerosol formation in regime 1, due to enhanced reactivity from the toluene products, such as the radicals from the photolysis of benzaldehyde. Water vapor has very little effect on the formation of aerosol volume, except that rates are slightly increased due to more OH radicals from reaction with 0(1D) from ozone photolysis. Increased temperature results in increased volume of aerosol formed in regime 1 (increased dinitrocresol formation), while increased photolysis rate results in increased rate of aerosol formation in regime 1. Both the rate and volume of aerosol formed in regime 2 are increased by increased temperature or photolysis rate. Both models indicate that the yield of secondary particulates from hydrocarbons (mass concentration aerosol formed/mass concentration hydrocarbon precursor) is proportional to the ratio [NOx]0/[hydrocarbon]0

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Airborne fine particles were collected at a suburban site in Queensland, Australia between 1995 and 2003. The samples were analysed for 21 elements, and Positive Matrix Factorisation (PMF), Preference Ranking Organisation METHods for Enrichment Evaluation (PROMETHEE) and Graphical Analysis for Interactive Assistance (GAIA) were applied to the data. PROMETHEE provided information on the ranking of pollutant levels from the sampling years while PMF provided insights into the sources of the pollutants, their chemical composition, most likely locations and relative contribution to the levels of particulate pollution at the site. PROMETHEE and GAIA found that the removal of lead from fuel in the area had a significant impact on the pollution patterns while PMF identified 6 pollution sources including: Railways (5.5%), Biomass Burning (43.3%), Soil (9.2%), Sea Salt (15.6%), Aged Sea Salt (24.4%) and Motor Vehicles (2.0%). Thus the results gave information that can assist in the formulation of mitigation measures for air pollution.

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The current investigation reports on diesel particulate matter emissions, with special interest in fine particles from the combustion of two base fuels. The base fuels selected were diesel fuel and marine gas oil (MGO). The experiments were conducted with a four-stroke, six-cylinder, direct injection diesel engine. The results showed that the fine particle number emissions measured by both SMPS and ELPI were higher with MGO compared to diesel fuel. It was observed that the fine particle number emissions with the two base fuels were quantitatively different but qualitatively similar. The gravimetric (mass basis) measurement also showed higher total particulate matter (TPM) emissions with the MGO. The smoke emissions, which were part of TPM, were also higher for the MGO. No significant changes in the mass flow rate of fuel and the brake-specific fuel consumption (BSFC) were observed between the two base fuels.

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This article follows the lead of several researchers who claim there is an urgent need to utilize insights from the arts, aesthetics and the humanities to expand our understanding of leadership. It endeavours to do this by exploring the metaphor of dance. It begins by critiquing current policy metaphors used in the leadership literature that present a narrow and functional view of leadership. It presents and discusses a conceptual model of leadership as dance that incorporates key dimensions such as context, dance and music and includes Polyani’s concept of connoisseurship. This article identifies some of the tensions that are inherent in both notions of dance and leadership. The final part of the article discusses the implications the model raises for broadening our understanding of leadership and school leadership preparation programmes. Three core implications raised here are (i) making space for alternative metaphors in leadership preparation programmes; (ii) providing opportunities to students of leadership to understand through alternative learning approaches and (iii) providing opportunities for engagement in alternative research agendas.

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The study of matrices of rare Type 4 carbonaceous chondrites can reveal important information on parent body rnetamorp~ic processes and provide a comparison with processes on parent bodies of ordinary chc-idrites. Reflectance spectra (Tholen, 1984) from the two largest asteroids in the asteroid belt, Ceres and Pallas, suggest that they may be metamorphosed carbonaceous chondrites. These two asteroids constitute - onethird of the mass in the asteroid belt implying that type 4-6 carbonaceous chondrites are poorly represented in the meteorite collection and may be of considerable importance. The matrix of the C4 chondrite Karoonda has been investigated using a JEOL 2000FX analytical electron microscope (AEM) with an attached Tracor-Northem TN5500 energy dispersive spectrometer (EDS). In previous studies (Scott and Taylor, 1985; Fitzgerald, 1979; Van Schmus, 1969), the petrography of the Karoonda matrix has been described as consisting largely of coarse-grained (50-200 urn in size) olivine and plagioclase (20-100 um in size), associated with micrometer sized magnetite and rare sulphides. AEM observations on matrix show that in addition to these large grains, there is a significant fraction (10 vol%) of interstitial fine grained phases « 5 urn). The mineralogy of these fine-grained phases differs in some respects from that of the coarser-grained matrix identified by optical and SEM techniques (Scott and Taylor, 1985; Fitzgerald, 1979; Van Schmus, 1969). I~ particular crystals of two compositionally distinct pyroxenes « 2 urn in size) have been identified which have not been previously observed in Karoonda by other analytical techniques. Thin film microanalyses (Mackinnon et al., 1986) of these two pyroxenes indicate compositions consistent with augite and low-Ca pyroxene (- Fs27). Fine-grained anhedral olivine « 2 urn size) is the most abundant phase with composition -Fa29' This composition is essentially indistinguishable from that determined for coarser-grained matrix olivines using an electron microprobe (Scott and Taylor, 1985; Fitzgerald, 1979; Van Schmus, 1969). All olivines are associated with subhedral magnetites « 1 urn size) which contain significant Cr (- 2%) and Al (- 1%) as was also noted for larger sized Karoonda magnetites by Delaney et al. (1985). It has recently been suggested (Burgess et al., 1987) on the basis of sulphur release profiles for S-isotope analyses of Karoonda that CaS04 (anhydrite) may be present. However, no sulphate phase has, as yet, been identified in the matrix of Karoonda. Low magnification contrast images suggest that Karoonda may have a significant porosity within the fine-grained matrix fraction. Most crystals are anhedral and do not show evidence for significant compaction. Individual grains often show single point contact with other grains which result in abundant intergranular voids. These voids frequently contain epoxy which was used as part of the specimen preparation procedure due to the friable nature of the bulk sample.

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In order to describe the total mineralogical diversity within primitive extraterrestrial materials, individual interplanetary dust particles (IDPs) collected from the stratosphere as part of the JSC Cosmic Dust Curatorial Program were analyzed using a var ...

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Quantities of Y2BaCuO5 powder greater than 500g have been manufactured by a co-precipitation process. By suitable heat treatments, the particle size of these powders can be varied from 5µm to less than 500nm. Sub-micrometer size powders may, under some conditions, have a duller green colour which is attributed to <2% unreacted material. However, after re-grinding and re-firing of this powder, high-purity powders can be achieved without significant grain growth. Inductively coupled plasma (ICP) spectroscopy is used to measure the stoichiometry of the powders and X-ray diffraction is used to determine phase purity. In both cases, the bulk composition is consistent with Y2BaCuO5 and phase purity is considered better than 95%.

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A method of producing particles having nano-sized grains comprises the steps of: (a) prepg. a soln. contg. one or more metal cations; (b) mixing the soln. from step (a) with one or more surfactants to form a surfactant/liq. mixt. and (c) heating the mixt. from step (b) above to form the particles. [on SciFinder(R)]

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A method of producing particles having nano-sized grains comprises the steps of: (a) prepg. a soln. contg. one or more metal cations; (b) mixing the soln. from step (a) with one or more surfactants to form a surfactant/liq. mixt. and (c) heating the mixt. from step (b) above to form the particles. [on SciFinder(R)]

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This thesis is focus on developing new photocatalysts for synthesis of fine organic chemicals on supported nanostructures. These photocatalysts can facilitate reactions by using visible light, moderate temperature and atmospheric pressure which is suitable for a sustainable, green and eco-friendly modern chemical industry. Both Semiconductor Photocatalyst and Noble Metal Photocatalysts are designed to facilitate the homocouplings reaction of imine generation by amines.

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Objectives To determine: (1) the accuracy of cytology scientists at assessing specimen adequacy by rapid on-site evaluation (ROSE) at fine needle aspiration (FNA) cytology collections; and (2) whether thyroid FNA with ROSE has lower inadequacy rates than non-attended FNAs. Methods The ROSE of adequacy for 3032 specimens from 17 anatomical sites collected over a 20-month period was compared with the final report assessment of adequacy. ROSE was performed by 19 cytology scientists. The report profile for 1545 thyroid nodules with ROSE was compared with that for 1536 consecutive non-ROSE thyroid FNAs reported by the same cytopathologists during the study period. Results ROSE was adequate in 75% (2276/3032), inadequate in 12% (366/3032) and in 13% (390/3032) no opinion was rendered. Of the 2276 cases assessed as adequate by ROSE, 2268 (99.6%) were finally reported as adequate for assessment; eight specimens had adequacy downgraded on the final report. Fifty eight per cent of cases with a ROSE assessment of inadequate were reported as adequate (212/366), whereas 93% (363/390) with no opinion rendered were reported as adequate. The overall final report adequacy rate for the 3032 specimens was 94% (2843/3032). Confirmation of a ROSE of adequacy at reporting was uniformly high amongst the 19 scientists, ranging from 98% to 100%. The inadequacy rate for thyroid FNAs with ROSE (6%) was significantly (P < 0.0001) lower than for non-ROSE thyroid FNAs (17%). A significantly (P = 0.02) higher proportion of adequate ROSE thyroid specimens was reported with abnormalities, compared with non-ROSE thyroid collections. Conclusions Cytology scientists are highly accurate at determining specimen adequacy at ROSE for a wide range of body sites. ROSE of thyroid FNAs can significantly reduce inadequate reports.

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This chapter uses as a beginning point Walter Benjamin’s famous essay ‘The work of art in the age of technological reproducibility’(1935/2008) to discuss Media Arts education. It locates ‘Media Arts’ at the intersection of three key ideas: 1) media arts products as objects for popular and everyday consumption and intervention by individuals and broader audiences; 2) materiality and how individuals use their bodies and technologies to produce, combine and share digital materials and; 3) the construction of aesthetic knowledge and how this relates to critical and conceptual thinking. These ideas are discussed in the context of the development of curriculum for students at all ages of schooling, with specific attention given to the knowledge and skills students might develop within Media Arts education in primary schools. Examples from a Media Arts project in a primary school in Australia – where a new Media Arts national curriculum has been developed –are provided to illustrate the key ideas discussed in the chapter.

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Driven by information accessibility-on-demand provided by the internet, education modes are changing from a teacher-led approach focused on content delivery and assessible outcomes, to a learner-based approach encouraging self-directed, peer-tutored, and cooperative learning. New pedagogies are required to extend learning beyond the classroom and traditional subject areas such as contemporary arts, in alignment with the cross disciplinary priorities of the Australian Curriculum and values of the International Baccalaureate Organisation. This research explores how partnerships with universities and cultural organisations are implicated in the generation of these new forms of pedagogy and contribute to the field of educational research within the context of Education Queensland’s Framework For Gifted Education. In particular, this paper explores a new pedagogical framework for highly capable year five to nine Queensland state school students at the intersection of arts, design and the sciences, which has arisen from an explicit secondary/ tertiary partnership between the Queensland University of Technology Creative Industries Faculty and Precincts and the Queensland Academies Young Scholars Program. The Young Scholars Program offers experiences in the International Baccalaureate and Australian Curriculum contexts to enhance outcomes via global understanding, unique industry partnerships and 21st century pedagogical innovation based not on 'content' but tacit/experiential learning concepts including immersive, creative, intellectual and social strategies. These strategies for highly capable students are centred around authentic opportunities, primary resources, transdisciplinary learning and relationships with likeminded peers including tertiary arts, design and STEM educators and students, professionals and researchers. The presentation details case studies which are hands-on real time workshops involving inquiry based challenges in the arts, design and sciences, mathematics, history, creative writing and other disciplines, with content drawn from collections from public institutions, academic research and tertiary pedagogy. Both programs implicate student collaboration and creative production as methodology/data capture for ongoing action research, in alignment with the Framework For Gifted Education’s emphasis on evidence-based practices. They also challenge gifted students “to continue their development through curricular activities that require depth of study, complexity of thinking, fast pace of learning, high-level skills development and/or creative and critical thinking (e.g. through independent investigations, tiered tasks, diverse real-world applications, mentors)”(Education Queensland, 2011:3). This presentation highlights the strengths of the ongoing collaboration between QUT Creative industries Faculty and Queensland Academies, which not only provides successful extra curricular activities for gifted students towards a place in the International Baccalaureate Program, but also provides mentoring opportunities for tertiary students in their field of endeavor to assist with their own learning, and unique research opportunities for the Faculty as it focuses on excellence in arts, design and creative education and research. Education Queensland.(2011). Framework For Gifted Education Revised Edition 2011 (accessed Nov 19 2011)