2,476 research outputs found

    G-BASE field procedures manual : version 1.1

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    The G-BASE project is a long-term systematic geochemical survey that has required a high degree of consistency in its sampling methodologies. This report gives in detail all the project procedures associated with the collection of geochemical samples from the planning phase in the office through to sample reception and reporting of the completed field campaign. The procedures described here should be diligently followed in order to maintain the high levels of quality control the project aspires to. Any changes to procedures are indicated in the latest version of this manual and documented in an updates list in Annex I. In addition to describing all the fieldwork procedures, the recruitment and training of "voluntary" student workers is described along with discussions relating to health and safety issues likely to be encountered during sampling. When describing the methods used by G-BASE in reports or publications, reference should be made to this manual

    GSUE: urban geochemical mapping in Great Britain

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    The British Geological Survey is responsible for the national strategic geochemical survey of Great Britain. As part of this programme, the Geochemical Surveys of Urban Environments (GSUE) project was initiated in 1992 and to date, 21 cities have been mapped. Urban sampling is based upon the collection of top (0.05 to 0.20 m) and deeper (0.35 to 0.50 m) soil samples on a 500 m grid across the built environment (1 sample per 0.25 km2). Samples are analysed for c. 46 total element concentrations by X-ray Fluorescence Spectrometry (XRFS), pH and loss on ignition (LOI) as an indicator of organic matter content. The data provide an overview of the urban geochemical signature and because they are collected as part of a national baseline programme, can be readily compared with soils in the rural hinterland to assess the extent of urban contamination. The data are of direct relevance to current UK land use planning, urban regeneration and contaminated land legislative regimes. An overview of the project and applications of the data to human health risk assessment, water quality protection and contaminant source identification are presented

    Clyde tributaries : report of urban stream sediment and surface water geochemistry for Glasgow

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    This report presents the results of an urban drainage geochemical survey carried out jointly by the British Geological Survey (BGS) and Glasgow City Council (GCC) during June 2003. 118 stream sediment and 122 surface water samples were collected at a sample density of 1 per 1 km2 from all tributaries draining into the River Clyde within the GCC administrative area. The study was carried out as part of the BGS systematic Geochemical Surveys of Urban Environments (GSUE) programme. Stream sediment and surface water samples underwent analysis for approximately 46 chemical elements including contaminants such as As, Al, Cd, Cu, Cr, Ni, Pb, Se, V and Zn according to standard GSUE procedures. In addition, parameters such as ammonium, asbestos and Hg as well as organic contaminants such as total petroleum hydrocarbons (TPH), polycyclic aromatic hydrocarbons (PAH), poly-chlorinated biphenyls (PCB) and organo-tin compounds were assessed. The aim of the project was to provide an overview of urban drainage geochemistry in Glasgow to link to an on-going sister project, which is investigating the geochemistry of the Clyde estuary. This report presents the initial findings of the Clyde tributaries survey but it is envisaged that the data will be interpreted in more detail as part of a wider Clyde basin study once the Clyde estuary survey is completed

    Asteroseismology across the HR diagram

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    High precision spectroscopy provides essential information necessary to fully exploit the opportunity of probing the internal structure of stars using Asteroseismology. In this work we discuss how Asteroseismology combined with High Precision Spectroscopy can establish a detailed view on stellar structure and evolution of stars across the HR diagramme.Comment: 6 pages, 2 figures - to appear in Precision Spectroscopy in Astrophysics, (Eds) L. Pasquini, M. Romaniello, N.C. Santos, and A. Correia, ESO Astrophysics Symposia, 200

    Zeroing in on more photons and gluons

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    We discuss radiation zeros that are found in gauge tree amplitudes for processes involving multi-photon emission. Previous results are clarified by examples and by further elaboration. The conditions under which such amplitude zeros occur are identical in form to those for the single-photon zeros, and all radiated photons must travel parallel to each other. Any other neutral particle likewise must be massless (e.g. gluon) and travel in that common direction. The relevance to questions like gluon jet identification and computational checks is considered. We use examples to show how certain multi-photon amplitudes evade the zeros, and to demonstrate the connection to a more general result, the decoupling of an external electromagnetic plane wave in the ``null zone". Brief comments are made about zeros associated with other gauge-boson emission.Comment: 26 page

    πΔΔ\pi \Delta\Delta coupling constant

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    We calculate the πΔΔ\pi \Delta\Delta coupling gπ0Δ++Δ++g_{\pi^0\Delta^{++}\Delta^{++}} using light cone QCD sum rule. Our result is gπ0Δ++Δ++=(11.8±2.0)g_{\pi^0\Delta^{++}\Delta^{++}}=(11.8\pm 2.0).Comment: RevTex, 5 pages + 1 PS figur

    Governance of Offshore IT Outsourcing at Shell Global Functions IT-BAM Development and Application of a Governance Framework to Improve Outsourcing Relationships

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    The lack of effective IT governance is widely recognized as a key inhibitor to successful global IT outsourcing relationships. In this study we present the development and application of a governance framework to improve outsourcing relationships. The approach used to developing an IT governance framework includes a meta model and a customization process to fit the framework to the target organization. The IT governance framework consists of four different elements (1) organisational structures, (2) joint processes between in- and outsourcer, (3) responsibilities that link roles to processes and (4) a diverse set of control indicators to measure the success of the relationship. The IT governance framework is put in practice in Shell GFIT BAM, a part of Shell that concluded to have a lack of management control over at least one of their outsourcing relationships. In a workshop the governance framework was used to perform a gap analysis between the current and desired governance. Several gaps were identified in the way roles and responsibilities are assigned and joint processes are set-up. Moreover, this workshop also showed the usefulness and usability of the IT governance framework in structuring, providing input and managing stakeholders in the discussions around IT governance

    The (d,6-Li) Reaction Studies

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    Supported by the National Science Foundation and Indiana Universit

    Three-dimensional AdS gravity and extremal CFTs at c=8m

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    We note that Witten's proposed duality between extremal c=24k CFTs and three-dimensional anti-de Sitter gravity may possibly be extended to central charges that are multiples of 8, for which extremal self-dual CFTs are known to exist up to c=40. All CFTs of this type with central charge 24 or higher, provided that they exist, have the required mass gap and may serve as candidate duals to three-dimensional gravity at the corresponding values of the cosmological constant. Here, we compute the genus one partition function of these theories up to c=88, we give exact and approximate formulas for the degeneracies of states, and we determine the genus two partition functions of the theories up to c=40.Comment: 17 pages, harvmac; v2: references added, version accepted in JHE

    A pulsating white dwarf in an eclipsing binary

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    White dwarfs are the burnt-out cores of Sun-like stars and are the fate of 97 per cent of the stars in our Galaxy. The internal structure and composition of white dwarfs are hidden by their high gravities, which causes all elements apart from the lightest ones to settle out of their atmospheres. The most direct method of probing the inner structure of stars and white dwarfs in detail is via asteroseismology. Here we present a pulsating white dwarf in an eclipsing binary system, enabling us to place extremely precise constraints on the mass and radius of the white dwarf from the lightcurve, independent of the pulsations. This 0.325-solar-mass white dwarf—one member of the SDSS J115219.99+024814.4 system—will serve as a powerful benchmark with which to constrain empirically the core composition of low-mass stellar remnants and to investigate the effects of close binary evolution on the internal structure of white dwarfs
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