931 resultados para (Pb, La)TiO3
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Imperial roads. The Italian colonial routes and their relationship with 1920-40 manuals
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The presence of arsenic in the environment is a hazard. The accumulation of arsenate by a range of cations in the formation of minerals provides a mechanism for the accumulation of arsenate. The formation of the tsumcorite minerals is an example of a series of minerals which accumulate arsenate. There are about twelve examples in this mineral group. Raman spectroscopy offers a method for the analysis of these minerals. The structure of selected tsumcorite minerals with arsenate and sulphate anions were analysed by Raman spectroscopy. Isomorphic substitution of sulphate for arsenate is observed for gartrellite and thometzekite. A comparison is made with the sulphate bearing mineral natrochalcite. The position of the hydroxyl and water stretching vibrations are related to the strength of the hydrogen bond formed between the OH unit and the AsO43- anion. Characteristic Raman spectra of the minerals enable the assignment of the bands to specific vibrational modes.
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Various researchers have called for an 'opening up' of Luhmann's systems theory. We take this short paper as an occasion for a critical reflection on the necessity, existence and possibilities of such an opening. We start by pointing out the inherent openness of Luhmann's theory, and, based on this, discuss three kinds of openings: the international opening, the theoretical opening and the empirical opening. With regard to the latter, we distinguish three general options of using Luhmann's theory for empirical research. Copyright © 2007 SAGE.
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The volcanic succession on Montserrat provides an opportunity to examine the magmatic evolution of island arc volcanism over a ∼2.5 Ma period, extending from the andesites of the Silver Hills center, to the currently active Soufrière Hills volcano (February 2010). Here we present high-precision double-spike Pb isotope data, combined with trace element and Sr-Nd isotope data throughout this period of Montserrat's volcanic evolution. We demonstrate that each volcanic center; South Soufrière Hills, Soufrière Hills, Centre Hills and Silver Hills, can be clearly discriminated using trace element and isotopic parameters. Variations in these parameters suggest there have been systematic and episodic changes in the subduction input. The SSH center, in particular, has a greater slab fluid signature, as indicated by low Ce/Pb, but less sediment addition than the other volcanic centers, which have higher Th/Ce. Pb isotope data from Montserrat fall along two trends, the Silver Hills, Centre Hills and Soufrière Hills lie on a general trend of the Lesser Antilles volcanics, whereas SSH volcanics define a separate trend. The Soufrière Hills and SSH volcanic centers were erupted at approximately the same time, but retain distinctive isotopic signatures, suggesting that the SSH magmas have a different source to the other volcanic centers. We hypothesize that this rapid magmatic source change is controlled by the regional transtensional regime, which allowed the SSH magma to be extracted from a shallower source. The Pb isotopes indicate an interplay between subduction derived components and a MORB-like mantle wedge influenced by a Galapagos plume-like source.
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Knowledge of the elements present in house dusts is important in understanding potential health effects on humans. In this study, dust samples collected from 10 houses in south-east Queensland have been analysed by scanning electron microscopy and X-ray microanalysis to measure the inorganic element compositions and to investigate the form of heavy metals in the dusts. The overall analytical results were then used to discriminate between different localities using chemometric techniques. The relative amounts of elements, particularly of Si, Ca, and Fe, varied between size fractions and between different locations for the same size fraction. By analysing individual small particles, many other constituents were identified including Ti, Cr, Mn, Ni, Cu, Zn, Ba, Ag, W, Au, Hg, Pb, Bi, La and Ce. The heavy metals were mostly concentrated in small particles in the smaller size fractions, which allowed detection by particle analysis, though their average concentrations were very low.
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Research on the sensual experience of place is not a mainstream topic in the architectural debate; it is more common in other disciplines like landscape architecture or interior design. The curriculum sometime offers opportunities of cross-pollination between disciplines; students in architecture courses might be exposed to different theories of space more typical to other fields. This paper explore the teaching/research nexus within QUT Master of Architecture research stream; the focus of the discussion is students’ experimentation with people’s experience and navigation of the public space. Theories of placemaking in relation to urban design are first introduced; then the teaching/research nexus is discussed; finally students’ experience in approaching phenomenological research within the Master of Architecture are presented.
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The natural and built environment has been shown to affect its users in both psychological and physiological forms. But can if affect the sociological aspects of human processes and actions? The activation of the public realm can be shown to reduce socially dysfunctional behaviour through the simple occupation of the space and a number of other key variables through its design. In order to explore this further we must study how public space is being used in terms of social interaction, which will lead to a set of design ideals through which the social activation of public space can be achieved. Observations of differing social contexts have been undertaken in order to solidify key ideas and design principles for the activation of public space. Three sites were selected, each containing different amounts of vegetation and opportunity for occupation. These were then analysed through a lens of levels of social interaction. In this way it can become evident how the users interact with and within their social environments Through the analysis of the chosen sites, it has become evident that levels of interaction between the users, whether for transitory or occupational purposes, rise directly with vegetation and opportunity for occupation. With this in mind it can be determined that through design, public space can allow for and create greater opportunity for social interaction.
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A growing body of researches provided evidence of the successful design in particular focus on design elements, ranging from colour, lighting, technology, landscape and spatial arrangement. However, no example or literature investigates the opportunities for linking these design elements in a practical base. Drawing upon existing architectural design theory, this paper investigates the relationship between design elements regards to public’s behavioural response to the public space. The aims of this paper are two-fold: first to examine whether there is a direct relationship between the two, and second to find out how the design elements could be coordinated together to influence not only the activities but also the environment, function and experience. To meet this objective, observation, behavioural mapping, interview and cognitive mapping methodologies are used. The present study involves two local case studies to find out the relationship between design elements in order to assist the design of a better public space for public activities. Correlation between the design elements shows that public activities is more likely to happen in relatively space with well balance of design. These finding provide a better understanding of public space design by gaining deeper perceptive between design and user’s behaviour, consequently improving social activities and interactions in public space. Moreover, it focuses on campus public areas which can be a vital aspect of university campus and play a valuable role in the overall success of public space design.
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An issue gaining prominence in our urban environments in the notion of lost space, the undesirable urban areas that are in need of redesign, commonly caused by a focus on development as individual architectural entities, without a greater view of the urban environment as a holistic entity. Within the context of South East Queensland, the suburb of Fortitude Valley has been earmarked for development as an extension of the current CBD. With lost and disused spaces already existing throughout the suburb due to rapid growth and mismatched developments, recent planning regimes have proposed rejuvenation in the form of proposals that echo typologies from other Australian regions, such as the laneway typology from Melbourne. Opportunities exist in these spaces for design approaches that relate specifically to the individual and unique subtropical character of the area. This research explores the relationship between innovative approaches towards urban greenery as a means to rejuvenate lost and disused public space, and its suitability within a subtropical climate, specifically focused within the suburb of Fortitude Valley. A trend gaining prominence is the notion of biophilic cities; cities that integrate urban greenery as a means to provide vibrant public spaces, and meet the growing aesthetic, social, cultural and economic needs of our cities. Through analysis of case studies showcasing greenery in an inventive way, observations of public using subtropical public space, and a discussion of the current policy frameworks at place within Fortitude Valley, innovative uses of urban greenery is proposed as viable placemaking technique in subtropical urban environments.
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This paper will focus on how Christos Tsiolkas the author of The Slap (2008) invites us to view the complex range of private lives of his male characters living in suburban Melbourne through their daily routines, conversations and innermost thoughts. On the surface most appear to be participating in and achieving a certain level of success in their lives. However, this novel reveals when we agitate and dig below the “practices of everyday life” there is often a disquiet simmering away under the facade of family harmony, male bravado and contentment. This paper will argue that as a result of dissatisfaction with the established order of their lives, each man has managed to create another level of meaning for himself, his own form of la perruque (De Certeau 2011: 29),the concept of living proposed by Michel De Certeau. A treatment of the characters in this article draws on, and is used to illustrate the paradigm.
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There is debate as to whether percutaneous coronary intervention (PCI) with drug-eluting stents or coronary artery bypass surgery (CABG) is the best procedure for subjects with type 2 diabetes and coronary artery disease requiring revascularization. There is some evidence that following these procedures there is less further revascularization with CABG than PCI in subjects with diabetes. Two recent studies; the FREEDOM (Future Revascularization Evaluation in patients with Diabetes mellitus: Optimal Management of Multivessel Disease) trial, and a trial using a real world diabetic population from a Registry, have shown that the benefits of CABG over PCI in subjects with type 2 diabetes extends to lower rates of death and myocardial infarct, in addition to lower rates of revascularization. However, the rates of stroke may be higher with CABG than PCI with drug-eluting stents in this population. Thus, if CABG is going to be preferred to PCI in subjects with type 2 diabetes and multivessel coronary disease, consideration should be given to how to reduce the rates of stroke with CABG.
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Black et al. (2004) identified a systematic difference between LA–ICP–MS and TIMS measurements of 206Pb/238U in zircons, which they correlated with the incompatible trace element content of the zircon. We show that the offset between the LA–ICP–MS and TIMS measured 206Pb/238U correlates more strongly with the total radiogenic Pb than with any incompatible trace element. This suggests that the cause of the 206Pb/238U offset is related to differences in the radiation damage (alpha dose) between the reference and unknowns. We test this hypothesis in two ways. First, we show that there is a strong correlation between the difference in the LA–ICP–MS and TIMS measured 206Pb/238U and the difference in the alpha dose received by unknown and reference zircons. The LA–ICP–MS ages for the zircons we have dated can be as much as 5.1% younger than their TIMS age to 2.1% older, depending on whether the unknown or reference received the higher alpha dose. Second, we show that by annealing both reference and unknown zircons at 850 °C for 48 h in air we can eliminate the alpha-dose-induced differences in measured 206Pb/238U. This was achieved by analyzing six reference zircons a minimum of 16 times in two round robin experiments: the first consisting of unannealed zircons and the second of annealed grains. The maximum offset between the LA–ICP–MS and TIMS measured 206Pb/238U for the unannealed zircons was 2.3%, which reduced to 0.5% for the annealed grains, as predicted by within-session precision based on counting statistics. Annealing unknown zircons and references to the same state prior to analysis holds the promise of reducing the 3% external error for the measurement of 206Pb/238U of zircon by LA–ICP–MS, indicated by Klötzli et al. (2009), to better than 1%, but more analyses of annealed zircons by other laboratories are required to evaluate the true potential of the annealing method.