6,189 research outputs found

    A numerical code for a three-dimensional magnetospheric MHD equilibrium model

    Get PDF
    Two dimensional and three dimensional MHD equilibrium models were begun for Earth's magnetosphere. The original proposal was motivated by realizing that global, purely data based models of Earth's magnetosphere are inadequate for studying the underlying plasma physical principles according to which the magnetosphere evolves on the quasi-static convection time scale. Complex numerical grid generation schemes were established for a 3-D Poisson solver, and a robust Grad-Shafranov solver was coded for high beta MHD equilibria. Thus, the effects were calculated of both the magnetopause geometry and boundary conditions on the magnetotail current distribution

    Energy and Entropy Fluxes in Coal Gasification and Liquefaction Processes

    Get PDF
    In the long-term studies on energy systems performed at IIASA, scenarios that provide for substitutes for fossil oil and gas are considered. In the future coal is expected to contribute to energy supplies to a greatly increasing extent only if it is converted to liquid or gaseous fuels or electricity. Coal conversion systems are rather complex, not only internally but also with respect to their exchanges with the environment; some use auxiliary energy, others yield byproducts. Therefore, the evaluation of such systems is not a simple task and the comparison of very different systems -- different in the nature of inputs and outputs -- must not be reduced to a comparison of energy efficiencies. Moreover, because these studies cover a long time period, it is necessary to estimate the potential development of related processes in order to determine the inputs required for producing substitute fuels. There are physical and chemical limitations to potential improvement. This paper outlines these constraints and provides means for the evaluation and comparison of different fuel synthesis processes, especially regarding methanol. The possibility of adding energy from nuclear or solar primary energy sources to such processes is discussed and the advantages are assessed

    Kustvattenfiskens kvicksilverbelastning och kondition

    Get PDF

    Sinisimpukan (Mytilus edulis L.) raskasmetallipitoisuuksia

    Get PDF

    Gennarbyviken och Gennarbyviksbassängen

    Get PDF

    Tungmetaller i den marina Tvärminnemiljön

    Get PDF
    • …
    corecore