1,621 research outputs found
Supertubes in Field Theories
To a domain wall or string object, Noether charge and topological spatial
objects can be attracted, forming a composite BPS
(Bogomolny-Prasad-Sommerfield) object. We consider two field theories and
derive a new BPS bound on composite linear solitons involving multiple charges.
Among the BPS objects `supertubes' appear when the wall or string tension is
canceled by the bound energy, and could take an arbitrary closed curve. In our
theories, supertubes manifest as Chern-Simons solitons, dyonic instantons,
charged semi-local vortices, and dyonic instantons on vortex flux sheet.Comment: latex, 10 page
Thermal conductivity of suspended pristine graphene measured by Raman spectroscopy
The thermal conductivity of suspended single-layer graphene was measured as a
function of temperature using Raman scattering spectroscopy on clean samples
prepared directly on a prepatterned substrate by mechanical exfoliation without
chemical treatments. The temperature at the laser spot was monitored by the
frequency of the Raman 2 band of the Raman scattering spectrum, and the
thermal conductivity was deduced by analyzing heat diffusion equations assuming
that the substrate is a heat sink at ambient temperature. The obtained thermal
conductivity values range from 1800 WmK near 325 K to
710 WmK at 500 K.Comment: 4pages, 3 figure
Holographic Nuclear Matter in AdS/QCD
We study the physics with finite nuclear density in the framework of AdS/QCD
with holographic baryon field included. Based on a mean field type approach, we
introduce the nucleon density as a bi-fermion condensate of the lowest mode of
the baryon field and calculate the density dependence of the chiral condensate
and the nucleon mass. We observe that the chiral condensate as well as the mass
of nucleon decrease with increasing nuclear density. We also consider the mass
splitting of charged vector mesons in iso-spin asymmetric nuclear matter.Comment: 16 pages, 3 figures, two references are added, typo corrected,
section 3.3 remove
Multicomponent Diffusion Systems.
This dissertation focuses on coupled multicomponent mass, heat, and charge transfer analyses of chemical and electrochemical systems. First, the Stefan-Maxwell multicomponent diffusion theory is introduced, along with constitutive laws for chemical and electrochemical potential. This set of model equations is then applied to various systems: gas diffusion in a tube, simultaneous mass and charge transfer in a convection battery, coupled heat and charge transfer in a prismatic lithium-ion battery, and coupled heat, mass, and charge transfer in a very-high-capacity lithium-ion cell.PhDMechanical EngineeringUniversity of Michigan, Horace H. Rackham School of Graduate Studieshttp://deepblue.lib.umich.edu/bitstream/2027.42/102361/1/sunung_1.pd
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