Open Access. Powered by Scholars. Published by Universities.®

Physical Sciences and Mathematics Commons

Open Access. Powered by Scholars. Published by Universities.®

Articles 1 - 6 of 6

Full-Text Articles in Physical Sciences and Mathematics

Analysis And Comparison Of Three Acoustic Energy Density Probes, Lance Lester Locey Oct 2004

Analysis And Comparison Of Three Acoustic Energy Density Probes, Lance Lester Locey

Theses and Dissertations

Traditional methods for the investigation of sound fields generally rely on a microphone to convert sound pressure into an electrical signal which can be recorded, displayed, and so forth. The squared sound pressure is directly related to potential energy density. Consequently, the measurement of sound pressure alone does not inherently provide insight into the total energy density of the sound field. Specifically, no information about the kinetic energy density of the sound field is available from this measurement alone. However, it is possible to use two microphones to estimate particle velocity. The squared particle velocity magnitude is directly related to …


Electronic Structure Properties And Bcs Superconductivity In Ss-Pyrochlore Oxides: KoSS₂O₆, Rolando Saniz, Julia E. Medvedeva, Lin Hui Ye, Tatsuya Shishidou, Arthur J. Freeman Sep 2004

Electronic Structure Properties And Bcs Superconductivity In Ss-Pyrochlore Oxides: KoSS₂O₆, Rolando Saniz, Julia E. Medvedeva, Lin Hui Ye, Tatsuya Shishidou, Arthur J. Freeman

Physics Faculty Research & Creative Works

We report a first-principles density-functional calculation of the electronic structure and properties of the recently discovered superconducting β-pyrochlore oxide KOs2O6. We find that the electronic structure near the Fermi energy EF is dominated by strongly hybridized Os 5d and O 2p states. A van Hove singularity very close to Ef leads to a relatively large density of states at EF, and the Fermi surface exhibits strong nesting along several directions. These features could provide the scattering processes leading to the observed anomalous temperature dependence of the resistivity and to the rather large …


Instantons In Quantum Mechanics And Resurgent Expansions, Ulrich D. Jentschura, Jean Zinn-Justin Aug 2004

Instantons In Quantum Mechanics And Resurgent Expansions, Ulrich D. Jentschura, Jean Zinn-Justin

Physics Faculty Research & Creative Works

Certain quantum mechanical potentials give rise to a vanishing perturbation series for at least one energy level (which as we here assume is the ground state), but the true ground-state energy is positive. We show here that in a typical case, the eigenvalue may be expressed in terms of a generalized perturbative expansion (resurgent expansion). Modified Bohr-Sommerfeld quantization conditions lead to generalized perturbative expansions which may be expressed in terms of nonanalytic factors of the form exp(-a/g), where a>0 is the instanton action, and power series in the coupling g, as well as logarithmic factors. The ground-state energy, for …


Effects Of Forage Nutritional Quality (Energy And Protein) On Deer Acceptance Of Foods Containing Secondary Metabolites, Dale L. Nolte, Bruce A. Kimball, Kelly R. Perry, Juan J. Villalba, Frederick D. Provenza Feb 2004

Effects Of Forage Nutritional Quality (Energy And Protein) On Deer Acceptance Of Foods Containing Secondary Metabolites, Dale L. Nolte, Bruce A. Kimball, Kelly R. Perry, Juan J. Villalba, Frederick D. Provenza

USDA Wildlife Services: Staff Publications


Deer foraging on tree seedlings is recognized as the most widespread detriment to reforestation efforts. Non-lethal approaches to reduce deer damage to seedlings are highly desirable. Avoidance of natural secondary metabolites contained in conifers may provide feasible means to develop non-lethal measures. Other studies have demonstrated that sheep and goats fed diets with high protein-to-energy ratios, or allowed to select between concentrates high in either energy or protein, ate much more of a high-terpene diet and of a high-tannin diet than when they were fed diets high in energy-to-protein ratios. Thus, manipulating foraging options for deer may impact their ability …


Qcd In Curved Space-Time: A Conformal Bag Model, Dmitri Kharzeev, Eugene Levin, Kirill Tuchin Jan 2004

Qcd In Curved Space-Time: A Conformal Bag Model, Dmitri Kharzeev, Eugene Levin, Kirill Tuchin

Kirill Tuchin

We construct an effective low energy Lagrangian using constraints imposed by the renormalization group. Degrees of freedom are gluons and a scalar glueball. This effective theory has a dual description as classical gluodynamics on a curved conformal background. Color fields are dynamically confined, and the strong coupling freezes at distances larger than the glueball size. We make specific predictions (in particular, on the Nc dependence of glueball properties) which can be tested in lattice simulations of gluodynamics.


Order-Parameter Symmetry And Mode-Coupling Effects At Dirty Superconducting Quantum Phase Transitions, Rastko Sknepnek, Thomas Vojta, Rajesh Narayanan Jan 2004

Order-Parameter Symmetry And Mode-Coupling Effects At Dirty Superconducting Quantum Phase Transitions, Rastko Sknepnek, Thomas Vojta, Rajesh Narayanan

Physics Faculty Research & Creative Works

We derive an order-parameter field theory for a quantum phase transition between a disordered metal and an exotic (non- s -wave) superconductor. Mode coupling effects between the order parameter and other fermionic soft modes lead to an effective long-range interaction between the anomalous density fluctuations which is reflected in singularities in the free energy functional. However, this long-range interaction is not strong enough to suppress disorder fluctuations. The asymptotic critical region is characterized by run-away flow to large disorder. For weak coupling, this asymptotic region is very narrow. It is preempted by a wide crossover regime with mean-field critical behavior …