217 research outputs found
Fuel cells as an energy source for desalination applications.
Nowadays, there is a renewed interest in fuel cell technology from industry and academia, electrochemistry and catalysis scientists. This interest is due to environmental legislations for CO2 and other greenhouse gases emissions (United Nations Environment Programme and the World Trade Organization, 2009) that demand the use of high efficiency energy production systems. Such systems have great potential in the area of desalination technology (Kenet, 2003, Al-Hallaj et al., 2004, Singh, 2008, Wang et al. 2011, Jones, 2013). Fuel cells are characterised by high operation efficiency, which results in decreased fuel consumption, and low environmental impact. A fuel cell is a device that converts the chemical energy of a fuel directly into electricity through electrochemical reactions, with low waste heat (e.g. SOFC in Fig. 1). The first fuel cell was fabricated back in 1830's, and slow but steady progress has been made toward their commercialization since then
Spin 3/2 Pentaquarks
We investigate the possible existence of the spin 3/2 pentaquark states using
interpolating currents with K-N color-octet structure in the framework of QCD
finite energy sum rule (FESR). We pay special attention to the convergence of
the operator product expansion
Magnetic moment of the pentaquark with light-cone QCD sum rules
In this article, we study the magnetic moment of the pentaquark state as diquark-diquark-antiquark () state in the
framework of the light-cone QCD sum rules approach. The numerical results
indicate the magnetic moment of the pentaquark state is about
.Comment: 10 pages, 1 figure. The main contents of this article is included in
hep-ph/0503007, this article will not be submitted to a journal for
publicatio
J/Psi Propagation in Hadronic Matter
We study J/ propagation in hot hadronic matter using a four-flavor
chiral Lagrangian to model the dynamics and using QCD sum rules to model the
finite size effects manifested in vertex interactions through form factors.
Charmonium breakup due to scattering with light mesons is the primary
impediment to continued propagation. Breakup rates introduce nontrivial
temperature and momentum dependence into the J/ spectral function.Comment: 6 Pages LaTeX, 3 postscript figures. Proceedings for Strangeness in
Quark Matter 2003, Atlantic Beach, NC, March 12-17, 2003; minor corrections
in version 2, to appear in J. Phys.
Progress in the determination of the cross section
Improving previous calculations, we compute the cross section using QCD sum rules. Our sum rules for the , , and hadronic
matrix elements are constructed by using vaccum-pion correlation functions, and
we work up to twist-4 in the soft-pion limit. Our results suggest that, using
meson exchange models is perfectly acceptable, provided that they include form
factors and that they respect chiral symmetry. After doing a thermal average we
get mb at T=150\MeV.Comment: 22 pages, RevTeX4 including 7 figures in ps file
Magnetic Moment of The Pentaquark State
We have calculated the magnetic moment of the recently observed
pentaquark in the framework of the light cone QCD sum rules using the photon
distribution amplitudes. We find that ,
which is quite small. We also compare our result with predictions of other
groups.Comment: 1 eps figure, 13 page
Nonfactorizable contributions in B decays to charmonium: the case of
Nonleptonic to charmonium decays generally show deviations from the
factorization predictions. For example, the mode has
been experimentally observed with sizeable branching fraction while its
factorized amplitude vanishes. We investigate the role of rescattering effects
mediated by intermediate charmed meson production in this class of decay modes,
and consider with the meson.
Using an effective lagrangian describing interactions of pairs of heavy-light
mesons with a quarkonium state, we relate this mode to the
analogous mode with in the final state. We find large enough to be measured at the factories, so that this decay
mode could be used to study the poorly known .Comment: RevTex, 16 pages, 2 eps figure
The Bethe ansatz as a matrix product ansatz
The Bethe ansatz in its several formulations is the common tool for the exact
solution of one dimensional quantum Hamiltonians. This ansatz asserts that the
several eigenfunctions of the Hamiltonians are given in terms of a sum of
permutations of plane waves. We present results that induce us to expect that,
alternatively, the eigenfunctions of all the exact integrable quantum chains
can also be expressed by a matrix product ansatz. In this ansatz the several
components of the eigenfunctions are obtained through the algebraic properties
of properly defined matrices. This ansatz allows an unified formulation of
several exact integrable Hamiltonians. We show how to formulate this ansatz for
a huge family of quantum chains like the anisotropic Heisenberg model,
Fateev-Zamolodchikov model, Izergin-Korepin model, model, Hubbard model,
etc.Comment: 4 pages and no figure
Hadron yields and spectra in Au+Au collisions at the AGS
Inclusive double differential multiplicities and rapidity density
distributions of hadrons are presented for 10.8 A GeV/c Au+Au collisions as
measured at the AGS by the E877 collaboration. The results indicate that large
amounts of stopping and collective transverse flow effects are present. The
data are also compared to the results from the lighter Si+Al system.Comment: 12 pages, latex, 10 figures, submitted to Nuclear Physics A (Quark
Matter 1996 Proceedings
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