3,133 research outputs found

    The Asymmetric Rotor. IX. The Heavy Water Bands at 2787 cm^–1 and 5373 cm^–1

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    The combination band (110) of the two stretching fundamentals of D2O is reported and analyzed to yield nu0=5373.2 cm^–1 and the excited state moments of inertia 1.910, 3.931, and 5.929×10^–40 g cm^2. The same method of analysis applied to the unsymmetrical fundamental band (100) envelope gives nu0=2787.5 cm^–1 and the excited state moments 1.881, 3.876, and 5.843×10^–40 g cm^2

    Pattern Formation and Dynamics in Rayleigh-B\'{e}nard Convection: Numerical Simulations of Experimentally Realistic Geometries

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    Rayleigh-B\'{e}nard convection is studied and quantitative comparisons are made, where possible, between theory and experiment by performing numerical simulations of the Boussinesq equations for a variety of experimentally realistic situations. Rectangular and cylindrical geometries of varying aspect ratios for experimental boundary conditions, including fins and spatial ramps in plate separation, are examined with particular attention paid to the role of the mean flow. A small cylindrical convection layer bounded laterally either by a rigid wall, fin, or a ramp is investigated and our results suggest that the mean flow plays an important role in the observed wavenumber. Analytical results are developed quantifying the mean flow sources, generated by amplitude gradients, and its effect on the pattern wavenumber for a large-aspect-ratio cylinder with a ramped boundary. Numerical results are found to agree well with these analytical predictions. We gain further insight into the role of mean flow in pattern dynamics by employing a novel method of quenching the mean flow numerically. Simulations of a spiral defect chaos state where the mean flow is suddenly quenched is found to remove the time dependence, increase the wavenumber and make the pattern more angular in nature.Comment: 9 pages, 10 figure

    The Bank's balance sheet during the crisis

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    This article sets out how monetary policy implementation and liquidity provision during the financial crisis have affected the size and composition of the Bank of England’s balance sheet. It extends and updates a recent speech by Paul Fisher, Executive Director Markets, and describes the main components of the Bank’s balance sheet prior to and during the crisis.

    Management of multi-method engineering design research: a case study

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    There is a need for a research management methodology that will utilise research methods on an individual basis and when combined in a multi-method approach. An agreed methodology would enable rapid progress in achieving agreement on the main issues within engineering design research. Researchers at the University of Glasgow have developed a conceptual management methodology, testing it on three engineering design research projects. This paper describes the methodology and presents results indicating its ability to enable rigorous triangulation of research results obtained via different methods and across different research projects forming the basis of an effective management tool

    An absorption tube for the investigation of gases in the photographic infrared

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    An absorption cell of novel design is described, which combines the advantages of long path and relatively small volume

    Rayleigh-Benard Convection with a Radial Ramp in Plate Separation

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    Pattern formation in Rayleigh-Benard convection in a large-aspect-ratio cylinder with a radial ramp in the plate separation is studied analytically and numerically by performing numerical simulations of the Boussinesq equations. A horizontal mean flow and a vertical large scale counterflow are quantified and used to understand the pattern wavenumber. Our results suggest that the mean flow, generated by amplitude gradients, plays an important role in the roll compression observed as the control parameter is increased. Near threshold the mean flow has a quadrupole dependence with a single vortex in each quadrant while away from threshold the mean flow exhibits an octupole dependence with a counter-rotating pair of vortices in each quadrant. This is confirmed analytically using the amplitude equation and Cross-Newell mean flow equation. By performing numerical experiments the large scale counterflow is also found to aid in the roll compression away from threshold but to a much lesser degree. Our results yield an understanding of the pattern wavenumbers observed in experiment away from threshold and suggest that near threshold the mean flow and large scale counterflow are not responsible for the observed shift to smaller than critical wavenumbers.Comment: 10 pages, 13 figure

    The stochastic dynamics of nanoscale mechanical oscillators immersed in a viscous fluid

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    The stochastic response of nanoscale oscillators of arbitrary geometry immersed in a viscous fluid is studied. Using the fluctuation-dissipation theorem it is shown that deterministic calculations of the governing fluid and solid equations can be used in a straightforward manner to directly calculate the stochastic response that would be measured in experiment. We use this approach to investigate the fluid coupled motion of single and multiple cantilevers with experimentally motivated geometries.Comment: 5 pages, 5 figure

    The pedagogy of proclamation: homiletical training among pastoral interns in the Evangelical Lutheran Church in America

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    https://place.asburyseminary.edu/ecommonsatsdissertations/1630/thumbnail.jp
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