7,077 research outputs found

    GW quasiparticle calculations with spin-orbit coupling for the light actinides

    Get PDF
    We report on the importance of GW self-energy corrections for the electronic structure of light actinides in the weak-to-intermediate coupling regime. Our study is based on calculations of the band structure and total density of states of Np, U, and Pu using a one-shot GW approximation that includes spin-orbit coupling within a full potential LAPW framework. We also present RPA screened effective Coulomb interactions for the f-electron orbitals for different lattice constants, and show that there is an increased contribution from electron-electron correlation in these systems for expanded lattices. We find a significant amount of electronic correlation in these highly localized electronic systems.Comment: Accepted and to appear in Phys. Rev.

    Analyzing the Impact of Excluding Rural People from Protected Forests: Spatial Resource Degradation and Rural Welfare

    Get PDF
    This paper examines how forest-dependent villagers meet a resource requirement when they are excluded from some area of a forest. Forest managers who value both pristine and degraded forest should take into account a .displacement effect. resulting in more intensive villager extraction elsewhere, and a .replacement effect. in which villagers purchase more of the resource from the market. Similarly, forest managers who have poverty concerns should recognize that exclusion zones tend to be more costly to villagers without market access and those with low opportunity costs of labour- typically the poorest villagers.

    Theoretical surface velocity distributions on acoustic splitter geometries for an engine inlet

    Get PDF
    The potential-flow velocity distributions on several splitter geometries in an engine inlet and their variation with different splitter leading-edge shapes and distances from the inlet highlight were analyzed. The velocity distributions on the inner and outer surfaces of the splitters are presented for low-speed and cruise conditions. At zero incidence angle, the splitter with the 4-to-1 elliptical leading edge had lower peak velocities and velocity gradients than the splitter with the 2-to-1 elliptical leading edge. The velocity gradients decreased as the distance from the inlet highlight to the splitter leading edge was increased. For a given distance, the peak velocity on the splitter inner surface increased with increasing inlet incidence angle. At an incidence angle of 50 deg, the velocity level and gradients on the inner surface of the splitter in the forward position were sufficiently severe to suggest local separation

    First-Principles-Based Thermodynamic Description of Solid Copper Using the Tight-Binding Approach

    Full text link
    A tight-binding model is fit to first-principles calculations for copper that include structures distorted according to elastic constants and high-symmetry phonon modes. With the resulting model the first-principles-based phonon dispersion and the free energy are calculated in the quasi-harmonic approximation. The resulting thermal expansion, the temperature- and volume-dependence of the elastic constants, the Debye temperature, and the Gruneisen parameter are compared with available experimental data.Comment: submitted to Physical Review
    corecore