60 research outputs found

    Surface enhancement of oxygen exchange and diffusion in the ionic conductor La2Mo2O9

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    Isotopic surface oxygen exchange and its subsequent diffusion have been measured using secondary ion mass spectrometry in the fast ionic conductor La2Mo2O9. A silver coating was applied to the sample surface to enhance the surface exchange process for dry oxygen. Contrary to previous studies performed using a wet atmosphere, no grain boundary diffusion tail was observed under these optimized dry exchange conditions. The activation energy for oxygen diffusion was found to be 0.66(+/- 0.09) eV at high temperature (>570 degrees C), and 1.25(+/- 0.01)eV at low temperature (<570 degrees C). Time-of-Flight secondary ion mass spectrometry was employed to investigate the correlation between the silver coating and the O-18 concentration on the sample surface. A close correlation between the presence of silver and oxygen incorporation on the surface was observed. (C) 2010 Elsevier B.V. All rights reserved

    A peer-to-peer network to support scholarly communication

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    The number of scientific journals and thereby the number of published articles grew with an enormous rate in the last century (e.g. Price 1986; Henderson 2002). In the second half of the 20th century the system seemed to abut against its boundaries, because in relation to research budgets, library budgets did not grow fast enough to cover all the scientific output produced. Price increases well above the inflation rate set by commercial publishers that bundle disproportionately high market power – especially for journals in the Science-Technical- Medicine-Sector in the last thirty years – intensified the situation even further. This situation is known as the serial crisis. New Information and Communication Technology (ICT) driven publication models are established and seem to be a promising way out of the crisis because they reduce distribution costs significantly. Especially the open access (OA) movement that advocates free electronic access to scientific output is subject to a fierce public debate. In this paper we will detail problems associated with OA and suggest a Peer-to-Peer (P2P) system that supports electronic scholarly communication as a tool to address the economic problems mentioned above

    The Bse and Cjd Crisis in the Press

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    The bovine spongiform encephalopathy (BSE) saga has made painfully evident the limitations of risk communication as a one-way avenue, where information to the public about the risks they face comes after critical policy decisions have already been made. In fact, communication has even been identified as one of the key elements of what went wrong and generated the loss of trust in government discourse and in beef in Europe. This book deals with risk communication as an evolving and interactive process between decision-makers and their publics and underlines the critical importance of creating mechanisms for interaction between policy-makers and stakeholders at all stages of policy-making, in order for risk communication to be effective. The book \u2013 the result of a research project carried out in four countries (Italy, Finland, Germany, Great Britain) by an international team of researchers in 2000-2002, supported by the European Commission DG Research and led by the World Health Organization \u2013 reports on research into the strategies used by different actors to communicate about BSE and Creutzfeldt-Jakob disease (CJD) in four European countries between 1985 and 2000. These actors include the mass media, health information systems, and political actors. The research also assessed the way people construct their perceptions about risk, who they listen to and how they make decisions on risk avoidance. A range of qualitative and quantitative methods used to describe what was said as well as was the perspectives and framework assumptions espoused by those different actors. This chapter addresses an important question raised by BSE/CJD: to what extent can the mass media be used as an index of public perception by policy-makers? The chapter presents results of empirical analysis of mass media coverage of the BSE/CJD issue in the four study countries since the early days of BSE. The analysis included the assessment of content, intensity and timing of media coverage, and the trajectory of the issues and frames used by the media. On a practical level, the chapter provides a methodology for the analysis of mass media reporting on risks, and tests the feasibility of implementing it in the four countries. On a conceptual level, the chapter looks beyond the case of BSE/CJD and surveillance systems in general to explore the idea of a "parallel epidemiology". It is conceived as "parallel" because, in addition to surveillance of BSE in the animal population and CJD in humans, there appears to be value in monitoring social representations of the problem. This is not an indicator of public perception but a measure of the waves of change in discourse by the media that have an impact on the public sphere and that both affect and draw from public perceptions. The chapter discusses the dual role of the media as a mirror of public opinion and as a contributor to the formation of public perceptions (including setting the public agenda)
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