557 resultados para CRITICAL-TEMPERATURE


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Increasingly, major insurers and reinsurers are operating on a global basis. For example, General Re Corporation and Cologne Re operate in almost 150 countries : see "General Re Corporation 1999 Annual Report". This is also true for the world's major brokers, and the emergence of large broking conglomerates such as Aon and Marsh are good examples of global service providers. Against the background of this increasingly global insurance market with global participants, there are a range of common legal issues in this article but a selection of certain critical matters are canvassed in the secitons below. First there are a range of regulatory issues that must be addressed. Secondly globalisation of the industry does create added incentive for a common legal regime to cover the formation of insurance transactions and the resolution of disputes about claims, coverage and termination. In this contect codifcation of insurance laws is a critical issue. Thirdly, major advances in genetic research and biotechnology over recent years have resulted in a dramatic increase in the availability of genetic testing. These developments have given rise to concerns worldwide about the potential for misuse of genetic information by third parties such as insurers and employers. Fourthly, the essence of an insurance transaction is the transference of risk from one person to anther. It is generally accepted that this transference should occur in informed circumstances and without undue advantage being bestowed upon either party. Finally this article will consider some legal matter in relation to transacting insurance on the internet

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In this thesis an investigation into theoretical models for formation and interaction of nanoparticles is presented. The work presented includes a literature review of current models followed by a series of five chapters of original research. This thesis has been submitted in partial fulfilment of the requirements for the degree of doctor of philosophy by publication and therefore each of the five chapters consist of a peer-reviewed journal article. The thesis is then concluded with a discussion of what has been achieved during the PhD candidature, the potential applications for this research and ways in which the research could be extended in the future. In this thesis we explore stochastic models pertaining to the interaction and evolution mechanisms of nanoparticles. In particular, we explore in depth the stochastic evaporation of molecules due to thermal activation and its ultimate effect on nanoparticles sizes and concentrations. Secondly, we analyse the thermal vibrations of nanoparticles suspended in a fluid and subject to standing oscillating drag forces (as would occur in a standing sound wave) and finally on lattice surfaces in the presence of high heat gradients. We have described in this thesis a number of new models for the description of multicompartment networks joined by a multiple, stochastically evaporating, links. The primary motivation for this work is in the description of thermal fragmentation in which multiple molecules holding parts of a carbonaceous nanoparticle may evaporate. Ultimately, these models predict the rate at which the network or aggregate fragments into smaller networks/aggregates and with what aggregate size distribution. The models are highly analytic and describe the fragmentation of a link holding multiple bonds using Markov processes that best describe different physical situations and these processes have been analysed using a number of mathematical methods. The fragmentation of the network/aggregate is then predicted using combinatorial arguments. Whilst there is some scepticism in the scientific community pertaining to the proposed mechanism of thermal fragmentation,we have presented compelling evidence in this thesis supporting the currently proposed mechanism and shown that our models can accurately match experimental results. This was achieved using a realistic simulation of the fragmentation of the fractal carbonaceous aggregate structure using our models. Furthermore, in this thesis a method of manipulation using acoustic standing waves is investigated. In our investigation we analysed the effect of frequency and particle size on the ability for the particle to be manipulated by means of a standing acoustic wave. In our results, we report the existence of a critical frequency for a particular particle size. This frequency is inversely proportional to the Stokes time of the particle in the fluid. We also find that for large frequencies the subtle Brownian motion of even larger particles plays a significant role in the efficacy of the manipulation. This is due to the decreasing size of the boundary layer between acoustic nodes. Our model utilises a multiple time scale approach to calculating the long term effects of the standing acoustic field on the particles that are interacting with the sound. These effects are then combined with the effects of Brownian motion in order to obtain a complete mathematical description of the particle dynamics in such acoustic fields. Finally, in this thesis, we develop a numerical routine for the description of "thermal tweezers". Currently, the technique of thermal tweezers is predominantly theoretical however there has been a handful of successful experiments which demonstrate the effect it practise. Thermal tweezers is the name given to the way in which particles can be easily manipulated on a lattice surface by careful selection of a heat distribution over the surface. Typically, the theoretical simulations of the effect can be rather time consuming with supercomputer facilities processing data over days or even weeks. Our alternative numerical method for the simulation of particle distributions pertaining to the thermal tweezers effect use the Fokker-Planck equation to derive a quick numerical method for the calculation of the effective diffusion constant as a result of the lattice and the temperature. We then use this diffusion constant and solve the diffusion equation numerically using the finite volume method. This saves the algorithm from calculating many individual particle trajectories since it is describes the flow of the probability distribution of particles in a continuous manner. The alternative method that is outlined in this thesis can produce a larger quantity of accurate results on a household PC in a matter of hours which is much better than was previously achieveable.

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This paper reports on the opportunities for transformational learning experienced by a group of pre-service teachers who were engaged in service-learning as a pedagogical process with a focus on reflection. Critical social theory informed the design of the reflection process as it enabled a move away from knowledge transmission toward knowledge transformation. The structured reflection log was designed to illustrate the critical social theory expectations of quality learning that teach students to think critically: ideology critique and utopian critique. Butin's lenses and a reflection framework informed by the work of Bain, Ballantyne, Mills and Lester were used in the design of the service-learning reflection log. Reported data provide evidence of transformational learning and highlight how the students critique their world and imagine how they could contribute to a better world in their work as a beginning teacher.

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This thesis critically analyses sperm donation practices from a child-centred perspective. It examines the effects, both personal and social, of disrupting the unity of biological and social relatedness in families affected by donor conception. It examines how disruption is facilitated by a process of mediation which is detailed using a model provided by Sunderland (2002). This model identifies mediating movements - alienation, translation, re-contextualisation and absorption - which help to explain the powerful and dominating material, and social and political processes which occur in biotechnology, or in reproductive technology in this case. The understanding of such movements and mediation of meanings is inspired by the complementary work of Silverstone (1999) and Sunderland. This model allows for a more critical appreciation of the movement of meaning from previously inalienable aspects of life to alienable products through biotechnology (Sunderland, 2002). Once this mediation in donor conception is subjected to critical examination here, it is then approached from different angles of investigation. The thesis posits that two conflicting notions of the self are being applied to fertility-frustrated adults and the offspring of reproductive interventions. Adults using reproductive interventions receive support to maximise their genetic continuity, but in so doing they create and dismiss the corresponding genetic discontinuity produced for the offspring. The offspring’s kinship and identity are then framed through an experimental postmodernist notion, presenting them as social rather than innate constructs. The adults using the reproductive intervention, on the other hand, have their identity and kinship continuity framed and supported as normative, innate, and based on genetic connection. This use of shifting frameworks is presented as unjust and harmful, creating double standards and a corrosion of kinship values, connection and intelligibility between generations; indeed, it is put forward as adult-centric. The analysis of other forms of human kinship dislocation provided by this thesis explores an under-utilised resource which is used to counter the commonly held opinion that any disruption of social and genetic relatedness for donor offspring is insignificant. The experiences of adoption and the stolen generations are used to inform understanding of the personal and social effects of such kinship disruption and potential reunion for donor offspring. These examples, along with laws governing international human rights, further strengthen the appeal here for normative principles and protections based on collective knowledge and standards to be applied to children of reproductive technology. The thesis presents the argument that the framing and regulation of reproductive technology is excessively influenced by industry providers and users. The interests of these parties collide with and corrode any accurate assessments and protections afforded to the children of reproductive technology. The thesis seeks to counter such encroachments and concludes by presenting these protections, frameworks, and human experiences as resources which can help to address the problems created for the offspring of such reproductive interventions, thereby illustrating why these reproductive interventions should be discontinued.

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This paper profiles Queensland's recent Crime and Misconduct Commission Inquiry into the abuse of children in foster care. The authors welcome the outcome as an opportunity to highlight the problems encountered by child protection jurisdictions in Australia and internationally, and they applaud some of the Inquiry's findings. However, the paper argues that the path to reform is hampered by insufficient accountability by government and management, and an inadequate challenge to the ideologies underpinning contemporary child protection policy and practice. The authors conclude with a call to value and assert social work's contribution to child protection systems so as to vastly improve outcomes for children and families.

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Zeolite N was produced from a variety of kaolinites and montmorillonites at low temperature (b100 °C) in a constantly stirred reactor using potassic and potassic+sodic mother liquors with chloride or hydroxyl anions. Reactions were complete (N95% product) in less than 20 h depending on initial batch composition and type of clay minerals. Zeolite N with 1.0bSi/Alb2.2 was produced under these conditions using KOH in the presence of KCl, NaCl, KCl+NaCl and KCl+NaOH. Zeolite N was also formed under high potassium molarities in the absence of KCl. Zeolite synthesis was more sensitive to water content and temperature when sodium was used in initial batch compositions. Syntheses of zeolite N by these methods were undertaken at bench, pilot and industrial scales.

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The challenge for all educators is to fuse the learning of information literacy to an academic education in such a way that the outcome is systematic and sustainable learning for students. This challenge can be answered through long-term commitment to information literacy education bound to organisation-wide, renewable strategic planning and driven through systemic reform. This chapter seeks to explore the two sides of reforming information literacy education in an academic environment. Specifically, it will examine how one Australian university has undertaken the implementation of a rigorous strategic, systemic approach to information literacy learning and teaching.

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This chapter provides an overview of the substantial and often neglected contribution of feminist theory and research to critical criminology. There are an array of feminist approaches to studying crime, violence and victimisation ( see Naffine 1997:29; Young 1996:34. this field of study has bourgeoned and diversified so much over the last decade that it would be a disservice to caricature it as simply "feminist". A range of influences and approaches from literary theory, jurisprudence, legal studies, cultural studies, postmodernism, neo-liberalism, post-colonialism and neo-Marxism are apparen across this large disparate body of work.

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Hot and cold temperatures significantly increase mortality rates around the world, but which measure of temperature is the best predictor of mortality is not known. We used mortality data from 107 US cities for the years 1987–2000 and examined the association between temperature and mortality using Poisson regression and modelled a non-linear temperature effect and a non-linear lag structure. We examined mean, minimum and maximum temperature with and without humidity, and apparent temperature and the Humidex. The best measure was defined as that with the minimum cross-validated residual. We found large differences in the best temperature measure between age groups, seasons and cities, and there was no one temperature measure that was superior to the others. The strong correlation between different measures of temperature means that, on average, they have the same predictive ability. The best temperature measure for new studies can be chosen based on practical concerns, such as choosing the measure with the least amount of missing data.

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A review of theoretical principals and practice of school-based approaches to critical literacy, with a specific focus on the middle years of schooling.

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Cold-formed steel beams are increasingly used as floor joists and bearers in residential, industrial and commercial buildings. Their structural behaviour and moment capacities are influenced by lateral-torsional buckling and hence a research study was undertaken to investigate the lateral-torsional buckling behaviour of cold-formed steel lipped channel beams at ambient and elevated temperatures. For this purpose a finite element model of a simply supported cold-formed steel lipped channel beam under uniform bending was developed first and validated using available numberical and experimental results. It was then used in a detailed parametric study to simulate the lateral-torsional behaviour of cold-formed steel beams under varying conditions. The moment capacity results were then compared with the predictions from the current ambient temperature design rules in Australia, New Zealand, American and European codes for cold-formed steel structures. Some very interesting results have been obtained. European design rules are found to be conservative while Australian and American design rules are unsafe. This paper presents the results of finite element analyses for ambient temperature conditions, and the comparison with the current design rules.

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The literature on critical thinking in higher education is constructed around the fundamental assumption that, while regarded as essential, is neither clearly or commonly understood. There is elsewhere evidence that academics and students have differing perceptions of what happens in university classrooms, particularly in regard to higher order thinking. This paper reports on a small-scale investigation in a Faculty of Education at an Australian University into academic and student definitions and understandings of critical thinking. Our particular interest lay in the consistencies and disconnections assumed to exist between academic staff and students. The presumption might therefore be that staff and students perceive critical thinking in different ways and that this may limit its achievement as a critical graduate attribute. The key finding from this study, contrary to extant findings, is that academics and students did share substantively similar definitions and understandings of critical thinking.

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Smart materials, such as thin-film piezoelectric polymers, are interesting for potential applications on Gossamer spacecraft. This investigation aims to predict the performance and long-term stability of the piezoelectric properties of poly(vinylidene fluoride) (PVDF) and its copolymers under conditions simulating the low-Earthorbit environment. To examine the effects of temperature on the piezoelectric properties of PVDF, poly(vinylidenefluoride-co-trifluoroethylene), and poly(vinylidenefluoride-cohexafluoropropylene), the d33 piezoelectric coefficients were measured up to 160 8C, and the electric displacement/electric field (D–E) hysteresis loops were measured from �80 to þ110 8C. The room-temperature d33 coefficient of PVDF homopolymer films, annealed at 50, 80, and 125 8C, dropped rapidly within a few days of thermal exposure and then remained unchanged. In contrast, the TrFE copolymer exhibited greater thermal stability than the homopolymer, with d33 remaining almost unchanged up to 125 8C. The HFP copolymer exhibited poor retention of d33 at temperatures above 80 8C. In situ D–E loop measurements from �80 to þ110 8C showed that the remanent polarization of the TrFE copolymer was more stable than that of the PVDF homopolymer. D–E hysteresis loop and d33 results were also compared with the deflection of the PVDF homopolymer and TrFE copolymer bimorphs tested over a wide temperature range.

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This paper presents a Critical Discourse Analysis (CDA) of four policy documents currently offering ‘sets of possibilities’ for the teaching of English as an additional or second language (hereafter EAL/ESL) in senior classrooms in Queensland, Australia. The aim is to identify the ways in which each document re-presents the notion of critical literacy. Leximancer software, and Fairclough’s textually-oriented discourse analysis method (2001, 2003) are used to interrogate the relevant sections of the documents for the ways in which they re-present (sic) and construct the discourses around critical language study. This paper presents the description, interpretation and explanation of the discourses in these documents which constitute part of a larger project in which teacher interviews and classroom teaching are also investigated for the ways in which ‘the critical’ is constructed and contested in knowledge and practice.