71,597 research outputs found
Saltless solar pond
A solar pond adapted for efficiently trapping and storing radiant solar energy without the use of a salt concentration gradient in the pond is disclosed. A body of water which may be fresh, saline, relatively clear or turbid, is substantially covered by a plurality of floating honeycomb panels. The honeycomb panels are made of a material such as glass which is pervious to short wave solar radiation but impervious to infrared radiation. Each honeycomb panel includes a multitude of honeycomb cells. The honeycomb panels are divided into the elongated honeycomb cells by a multitude of intermediate plates disposed between a bottom plate and top plate of the panel. The solar pond is well suited for providing hot water of approximately 85 to 90 C temperature for direct heating applications, and for electrical power generation
Regional applicability and potential of salt-gradient solar ponds in the United States. Volume 1: Executive summary
Findings of a survey concerning salt ponds are summarized. The residential, commercial, and institutional buildings sector is discussed. The industrial process heat sector is considered. The agricultural process heat sector is examined. The electrical power sector is reviewed. The desalinization sector is considered
Path integral for a relativistic Aharonov-Bohm-Coulomb system
The path integral for the relativistic spinless Aharonov-Bohm-Coulomb system
is solved, and the energy spectra are extracted from the resulting amplitude.Comment: 6 pages, Revte
Mass Spectrum and Bounds on the Couplings in Yukawa Models With Mirror-Fermions
The symmetric Yukawa model with mirror-fermions
in the limit where the mirror-fermion is decoupled is studied both analytically
and numerically. The bare scalar self-coupling is fixed at zero and
infinity. The phase structure is explored and the relevant phase transition is
found to be consistent with a second order one. The fermionic mass spectrum
close to that transition is discussed and a first non-perturbative estimate of
the influence of fermions on the upper and lower bounds on the renormalized
scalar self-coupling is given. Numerical results are confronted with
perturbative predictions.Comment: 7 (Latex) page
-Particle Spectrum in the Reaction p+B
Using a simple phenomenological parametrization of the reaction amplitude we
calculated -particle spectrum in the reaction p+B at the resonance proton energy 675 KeV. The parametrization
includes Breit-Wigner factor with an energy dependent width for intermediate
state and the Coulomb and the centrifugal factors in -particle
emission vertexes. The shape of the spectrum consists of a well defined peak
corresponding to emission of the primary and a flat shoulder going
down to very low energy. We found that below 1.5 MeV there are 17.5% of
's and below 1 MeV there are 11% of them.Comment: 6 pages, 3 figure
Driven classical diffusion with strong correlated disorder
We analyze one-dimensional motion of an overdamped classical particle in the
presence of external disorder potential and an arbitrary driving force F. In
thermodynamical limit the effective force-dependent mobility mu(F) is
self-averaging, although the required system size may be exponentially large
for strong disorder. We calculate the mobility mu(F) exactly, generalizing the
known results in linear response (weak driving force) and the perturbation
theory in powers of the disorder amplitude. For a strong disorder potential
with power-law correlations we identify a non-linear regime with a prominent
power-law dependence of the logarithm of mu(F) on the driving force.Comment: 4 pages, 2 figures include
Configuration-Space Location of the Entanglement between Two Subsystems
In this paper we address the question: where in configuration space is the
entanglement between two particles located? We present a thought-experiment,
equally applicable to discrete or continuous-variable systems, in which one or
both parties makes a preliminary measurement of the state with only enough
resolution to determine whether or not the particle resides in a chosen region,
before attempting to make use of the entanglement. We argue that this provides
an operational answer to the question of how much entanglement was originally
located within the chosen region. We illustrate the approach in a spin system,
and also in a pair of coupled harmonic oscillators. Our approach is
particularly simple to implement for pure states, since in this case the
sub-ensemble in which the system is definitely located in the restricted region
after the measurement is also pure, and hence its entanglement can be simply
characterised by the entropy of the reduced density operators. For our spin
example we present results showing how the entanglement varies as a function of
the parameters of the initial state; for the continuous case, we find also how
it depends on the location and size of the chosen regions. Hence we show that
the distribution of entanglement is very different from the distribution of the
classical correlations.Comment: RevTex, 12 pages, 9 figures (28 files). Modifications in response to
journal referee
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