26,300 research outputs found
Intersection multiplicities over Gorenstein rings
We construct a complex of free-modules over a Gorenstein ring R of dimension
five, for which the Euler characteristic and Dutta multiplicity are different.
This complex is the resolution of an R-module of finite length and finite
projective dimension. As a consequence, the ring R has a nonzero Todd class
tau_3(R) and a bounded free complex whose local Chern character does not vanish
on this class.
In the course of our work, we construct a module N of finite length and
finite projective dimension over the hypersurface A=K[u,v,w,x,y,z]/(ux+vy+wz),
such that the Serre intersection multiplicity of the modules N and A/(u,v,w)A
is -2
Electronic structure of S-C6H5 self-assembled monolayers on Cu(111) and Au(111) substrates
We use first principles density functional theory to calculate the electronic
structure of the phenylthiolate (S-CH) self-assembled monolayer (SAM)
on Cu(111) and Au(111) substrates. We find significant lateral dispersion of
the SAM molecular states and discuss its implications for transport properties
of the molecular wire array. We calculate the two photon photoemission spectra
and the work function of the SAM on Cu(111) and compare them with the available
experimental data. Our results are used to discuss assignments of the observed
spectral data and yield predictions for new electronic states due to the
monolayer not yet accessed experimentally.Comment: 7 pages, 7 figure
A first-order differential double subordination with applications
Let and belong to a certain class of normalized analytic
univalent functions in the open unit disk of the complex plane. Sufficient
conditions are obtained for normalized analytic functions to satisfy the
double subordination chain . The differential
sandwich-type result obtained is applied to normalized univalent functions and
to -like functions
Specific heat study of the Na(0.3)CoO(2).1.3H(2)O superconductor: influence of the complex chemistry
We report results of specific heat measurements on polycrystalline samples of
the layered superconductor, Na(0.3)CoO(2).1.3H(2)O. The electronic contribution
to the specific heat, gamma, is found to be 12.2 mJ/mol-K2. The feature at the
superconducting transition is rather sharp, becoming broad and strongly
suppressed in an applied magnetic field. The data indicate a residual normal
state electronic specific heat at low temperatures, implying that there is a
sizable population of normal state electrons in the samples even below Tc.
Inhomogeneity in the Na content, to which the superconducting state is
exquisitely sensitive, appears to be the most likely explanation for these
results. These results further indicate that special sample handling is
required for an accurate characterization of the superconducting state in this
material.Comment: publication information adde
Phase transitions of barotropic flow coupled to a massive rotating sphere - derivation of a fixed point equation by the Bragg method
The kinetic energy of barotropic flow coupled to an infnitely massive
rotating sphere by an unresolved complex torque mechanism is approximated by a
discrete spin-lattice model of fluid vorticity on a rotating sphere, analogous
to a one-step renormalized Ising model on a sphere with global interactions.
The constrained energy functional is a function of spin-spin coupling and spin
coupling with the rotation of the sphere. A mean field approximation similar to
the Curie-Weiss theory, modeled after that used by Bragg and Williams to treat
a two dimensional Ising model of ferromagnetism, is used to find the barotropic
vorticity states at thermal equilibrium for given temperature and rotational
frequency of the sphere. A fixed point equation for the most probable
barotropic flow state is one of the main results.Comment: 31 pages, 6 figure
- …