72,750 research outputs found
Analytical solutions for quasi-geostrophic inertial modes and onset of thermal convection in rapidly rotating spheroids
A simple variational principle for classical spinning particle with anomalous magnetic momentum
We obtain Bargmann-Michel-Telegdi equations of motion of classical spinning
particle using Lagrangian variational principle with Grassmann variables.Comment: 3 pages, late
On direction of spontaneous magnetization in a "cubic" ferromagnet
The magnetic properties of anisotropic films have been studied using
3D-neutron polarization analysis. The experimental facts refer to essential
distinction of the sample states, magnetized in opposite directions. For an
explanation of asymmetrical effects the model is offered, in which the
fundamental theoretical principles of structural phase transitions are used.Comment: 4 pages LaTeX (phbauth) and 4 figures (epsfig
Comparison of CâC bond hydrogenation in C-4 unsaturated nitriles over Pt/alumina
The hydrogenation of allyl cyanide (but-1-ene-4-nitrile, AC), trans- and cis-crotononitrile (E- and Z-but-2-ene nitrile, TCN and CCN), and methacrylonitrile (2-cyano-1-propene, MCN) were studied, both singly and competitively, over a Pt/alumina catalyst in the liquid phase. Each unsaturated nitrile only underwent CâC bond hydrogenation: no evidence was found for the formation of the saturated or unsaturated amine. The nonconjugated allyl cyanide was found to be the most reactive unsaturated nitrile. Activation energies for the hydrogenation of the CâC bond in AC and MCN were determined giving values of 64 ± 7 kJ molâ1 for AC and 37 ± 4 kJ molâ1 for MCN. The reaction was zero order for both nitriles. Competitive hydrogenations revealed that not only does allyl cyanide react preferentially over the other isomers but also it inhibits the hydrogenation of the other isomers. When all four nitriles were simultaneously hydrogenated, inhibition effects were easily seen suggesting that in terms of strength of bonding to the surface an order of AC > CCN > TCN ⌠MN can be generated
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The 2009 R-ISEW (regional index of sustainable economic well-being) for all the English regions
This latest report presents new data calculated in 2009 for the years 1994â2007. The data, which also includes the updating of several sets of figures that previously had to be estimated for 2006, show that a nine-year increase in the English R-ISEW since 1994, began to peter out in 2003, such that total per capita growth between 2003 and 2007 was only 2.4%. Indeed, between 2005 and 2006, per capita R-ISEW fell slightly
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The 2010 R-ISEW (regional index of sustainable economic well-being) for all the English regions
This is the fourth consecutive report presenting R-ISEW (regional index of sustainable economic well-being) calculations for the nine Government Office Regions (GORs) of England.1 New data available in the summer of 2010 allows a continuous time series from 1994 to 2008 â 15 years. Because of the nature of the data required for the R-ISEW, there is always a two-year lag before results for any given year can be completed
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Regional index of sustainable economic well-being development project: final report
This report presents results from a development project carried out by nef (the new economics foundation) on behalf of emda (the East Midlands Development Agency) and Natural England, to improve the methodologies used in the calculation of the R-ISEW (Regional Index of Sustainable Economic Well-Being)
Oscillations of a Bose-Einstein condensate rotating in a harmonic plus quartic trap
We study the normal modes of a two-dimensional rotating Bose-Einstein
condensate confined in a quadratic plus quartic trap. Hydrodynamic theory and
sum rules are used to derive analytical predictions for the collective
frequencies in the limit of high angular velocities, , where the vortex
lattice produced by the rotation exhibits an annular structure. We predict a
class of excitations with frequency in the rotating frame,
irrespective of the mode multipolarity , as well as a class of low energy
modes with frequency proportional to . The predictions are in good
agreement with results of numerical simulations based on the 2D
Gross-Pitaevskii equation. The same analysis is also carried out at even higher
angular velocities, where the system enters the giant vortex regime.Comment: 4 pages, 2 figure
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