Volcanic Gas Workshop Features State-of-the-Art Measurement Techniques

info:eu-repo/semantics/published

Surface area, porosity and water adsorption properties of fine volcanic ash particles

Our understanding on how ash particles in volcanic plumes react with coexisting gases and aerosols is still rudimentary, despite the importance of these reactions in influencing the chemistry and dynamics of a plume. In this study, six samples of fine ash (<100 μm) from different volcanoes were measured for their specific surface area, as, porosity and water adsorption properties with the aim to provide insights into the capacity of silicate ash particles to react with gases, including water vapour. To do so, we performed high-resolution nitrogen and water vapour adsorption/desorption experiments at 77 K and 303 K, respectively. The nitrogen data indicated as values in the range 1.1-2.1 m2/g, except in one case where as of 10 m2/g was measured. This high value is attributed to incorporation of hydrothermal phases, such as clay minerals, in the ash surface composition. The data also revealed that the ash samples are essentially non-porous, or have a porosity dominated by macropores with widths >500 Å All the specimens had similar pore size distributions, with a small peak centered around 50 Å These findings suggest that fine ash particles have relatively undifferentiated surface textures, irrespective of the chemical composition and eruption type. Adsorption isotherms for water vapour revealed that the capacity of the ash samples for water adsorption is systematically larger than predicted from the nitrogen adsorption as values. Enhanced reactivity of the ash surface towards water may result from (i) hydration of bulk ash constituents; (ii) hydration of surface compounds; and/or (iii) hydroxylation of the surface of the ash. The later mechanism may lead to irreversible retention of water. Based on these experiments, we predict that volcanic ash is covered by a complete monolayer of water under ambient atmospheric conditions. In addition, capillary condensation within ash pores should allow for deposition of condensed water on to ash particles before water reaches saturation in the plume. The total mass of water vapour retained by 1 g of fine ash at 0.95 relative water vapour pressure is calculated to be ∼10-2 g. Some volcanic implications of this study are discussed. © Springer-Verlag 2004.

Symmetrical freedom quilts: the ethnomathematics of ways of communication, liberation, and art

Symmetrical Freedom Quilts may be considered as links between mathematics, history, ethnomathematics, and the art of quilting. A quilt theme is a pedagogical way to integrate mathematics, art, and history in an interdisciplinary approach. This article combines an ethnomathematical-historical perspective by elaborating a history project related to the Underground Railroad. This work will allow teachers to develop classroom projects that help students to better understand geometry, especially concepts of symmetry and transformations. One of the objectives of this project is to stimulate student’s creativity and interest, because quilts may be considered as cultural and mathematical expressions of student’s daily life.

[Book review] Colour: Art and Science

Tony Mann provides a review of the book: Trevor Lamb & Janine Bourriau (Eds.) Colour: Art and Science, 1995. (Darwin College Lectures), Cambridge University Press, 237pp. ISBN: 0521-49645-4 (hbk.) 0521-49963-1 (pbk.)

Ultra-fine pitch flip-chip assembly using isotropic conductive adhesives

This paper discusses results from a highly interdisciplinary research project which investigated different packaging options for ultra-fine pitch, low temperature and low cost flip-chip assembly. Isotropic Conductive Adhesives (ICAs) are stencil printed to form the interconnects for the package. ICAs are utilized to ensure a low temperature assembly process of flip-chip copper column bumped packages. Results are presented on the structural integrity of novel electroformed stencils. ICA deposits at sub-100 micron pitch and the subsequent thermo-mechanical behaviour of the flip-chip ICA joints are analysed using numerical modelling techniques. Optimal design rules for enhanced performance and thermomechanical reliability of ICA assembled flip-chip packages are formulated.

[Book review] Piero della Francesca: A Mathematician's art by J.V. Field, Yale University Press.

Review of the book 'Piero della Francesca: A Mathematician’s Art' by J.V. Field, Yale University Press, 420 pp, £35 ISBN 0300103425.

High current density induced damage mechanisms in electronic solder joints: a state-of-the-art review

High current density induced damages such as electromigration in the on-chip interconnection /metallization of Al or Cu has been the subject of intense study over the last 40 years. Recently, because of the increasing trend of miniaturization of the electronic packaging that encloses the chip, electromigration as well as other high current density induced damages are becoming a growing concern for off-chip interconnection where low melting point solder joints are commonly used. Before long, a huge number of publications have been explored on the electromigration issue of solder joints. However, a wide spectrum of findings might confuse electronic companies/designers. Thus, a review of the high current induced damages in solder joints is timely right this moment. We have selected 6 major phenomena to review in this paper. They are (i) electromigration (mass transfer due electron bombardment), (ii) thermomigration (mass transfer due to thermal gradient), (iii) enhanced intermetallic compound growth, (iv) enhanced current crowding, (v) enhanced under bump metallisation dissolution and (vi) high Joule heating and (vii) solder melting. the damage mechanisms under high current stressing in the tiny solder joint, mentioned in the review article, are significant roadblocks to further miniaturization of electronics. Without through understanding of these failure mechanisms by experiments coupled with mathematical modeling work, further miniaturization in electronics will be jeopardized

Trembling the plane of immanence: media arts philosophy and the re-vision of art (or what’s acoustics got to do with the visual?)

Invited lecture at the Royal Academy of Art.

To tremble the zero: art in the age of algorithmic reproduction

'To Tremble the Zero: Art in the Age of Algorithmic Reproduction' is a philosophic, political and sensuous journey playing with (and against) Benjamin's 'Art in the Age of Mechanical Reproduction'. In an age inundated by the 'post-': postmodernity, posthuman, post art, postsexual, post-feminist, post-society, post-nation, etc, 'To Tremble the Zero' sets out to re/present the nature of what it means to do or make 'art', as well as what it means to be or have 'human/ity' when the ground is nothing other than the fractal, and algorithmically infinite, combinations of zero and one. The work will address also the unfortunate way in which modern forms of metaphysics continue to creep 'unsuspectingly' into our understanding of contemporary media/electronic arts, despite (or perhaps even because of) the attempts by Latour, Badiou, or Agamben especially when addressing the zero/one as if a contradictory 'binary' rather than as a kind of 'slice' or (to use Deleuze and Guattari) an immanent plane of immanence. This work argues that by retrieving Benjamin, Einstein, Gödel, and Haraway, a rather different story of art can be told.

Art always at heart

The Art Workers Guild, brother body to the SPAB and once presided over by William Morris and his followers, is 125 years old this year. Alan Powers looks back over its history, and sheds light on the characters and common bonds between the two bodies – while present Brothers of the Guild are pictured at work by photographer Lara Platman for new book to mark the event.

The art of auscultation: evaluating a patient's respiratory pathology

This article considers national policy drivers promoting the development of advanced assessment skills and practical procedures for the safe and effective use of the stethoscope in the clinical area. The evidence base underpinning effective use of the stethoscope in clinical practice is explored, including the preparation of the patient and the environment, applying infection control policies, and placing an emphasis on privacy and dignity. This is followed by a practical guide to auscultation technique of the respiratory system for nurses developing advanced practice skills.

Spank performance tour [at National Review of Live Art 2008]

Spank is a duet about two women’s journeys as they play out different roles. One woman recalls stinging anecdotes marked by intimacy, jealousy, fear and fantasy from her childhood in the 70s suburbs – round the corner from where Mike Leigh would film Life Is Sweet. Her Double (projected on screen) reads from a newspaper about an event that punctured the local community, creating an enduring cultural scar, her voice lacking emotion. Both women must eventually face one another and ask, who is deceiving whom? The consequences of guilt and shame and the unstable shift from private memory to public consequence is inevitable and deadly.[ABSTRACT BY THE AUTHOR]

Hide and seek with rebels: tracing contemporary queer art in cracks and rips

This Article does not have an abstract.