2,158 research outputs found
Electrochemical aspects of the electroforming of iron
The patent literature describing the development of the
foil electroforming technology has been reviewed. A review
of the literature covering the development of iron plating
electrolytes has also been completed.
A detailed study of the effects of solution parameters
on the conductivity of iron chloride solution and the effect
of addition of a number of 'conductivity salts' has been carried out. The operation of a pilot plant for the continuous
production of iron foil has. been investigated and the
parameters of foil production characterised.
Preliminary cathodic polarization studies were made at
low current densities on the iron chloride electrolyte showing
the effects of temperature on the system. A number of possible materials for use as insoluble anodes
have been investigated using anodic polarization to determine·
their behaviour in the aggressive hot iron chloride electrolyte
environment. The possibility of reducing depassivation of
the cathode by the addition of a less aggressive anion was
studied but no significant improvement achieved.
For a more detailed and controlled study of the hot iron
chloride electrolyte, a closed, divided-cell incorporating
a rotating-cylinder electrode was designed and constructed to operate near to the boiling polnt.of the electrolyte.
The cell enabled a more rigorous-study of the electrolyte to be
made as the solution parameters could be better controlled. The concentration of the ferric ion in the solution could be
reduced and held constant while other factors could be measured.
This system has been used to demonstrate the electrochemical
reduction of ferric ion in addition to demonstrating that
chemical reduction of the electrolyte was feasible and to study the effect of ferric ion concentration on cathode current
efficiency. Control of ferric ion concentration by use of
the divided cell has also enabled study of some of the deposition
characteristics, the effects of stirring on the deposit
and an investigation into the use of surface-active agents in
further optimising the electrolyte performance
Tracking the Equator Into the Paleogene (abstract of paper presented at AGU Fall Meeting, San Francisco, 8-12 Dec 2003)
Stratigraphy has been compiled for 63 tropical Pacific drill sites that sample lower Neogene and Paleogene sediments. These Sites derive from drilling on DSDP Leg 5 through ODP Leg 199. All Sites have been put on the biostratigraphic and paleomagnetic timescale refined by Leg 199 scientists. Sediment accumulation rates have been calculated for ten intervals ranging in age from 10 Ma to 56 Ma. A simple fixed hotspot model was used for Pacific lithospheric plate rotation in reconstructing the position of the selected sites for each of these ten intervals. The reconstruction of all intervals show the development of a tongue of relatively high accumulation rates associated with the oceanographic divergence at the geographic equator. The estimated position of the geographic equator based on these reconstructions lies consistently south of the position of the equator based on the rotation model used. However, the southward displacement is generally 2 degrees of latitude or less. We believe that this relatively small disagreement between the two estimates of equatorial position back to 56 Ma indicates: 1) Whatever hotspot movement that may have occurred in the interval between 40 and 56 Ma did not affect the motion of the Pacific plate; its motion after 40 Ma appears to have been approximately the same as before 40 Ma. 2) The estimated rate of true polar wander during the interval of 40 - 56 Ma must be very small (~0.125/m.y.) and is probably not significant (i.e., well within the error of these reconstructions)
Mesoscale convective vortex formation in a weakly sheared moist neutral environment
J. Atmos. Sci., 64, 1443-1466The article of record as published may be located at http://dx.doi.org/10.1175/JAS3898.
Creating Bell states and decoherence effects in quantum dots system
We show how to improve the efficiency for preparing Bell states in coupled
two quantum dots system. A measurement to the state of driven quantum laser
field leads to wave function collapse. This results in highly efficiency
preparation of Bell states. The effect of decoherence on the efficiency of
generating Bell states is also discussed in this paper. The results show that
the decoherence does not affect the relative weight of and in the
output state, but the efficiency of finding Bell states.Comment: 4 pages, 2figures, corrected some typo
Fredholm Determinants, Differential Equations and Matrix Models
Orthogonal polynomial random matrix models of NxN hermitian matrices lead to
Fredholm determinants of integral operators with kernel of the form (phi(x)
psi(y) - psi(x) phi(y))/x-y. This paper is concerned with the Fredholm
determinants of integral operators having kernel of this form and where the
underlying set is a union of open intervals. The emphasis is on the
determinants thought of as functions of the end-points of these intervals. We
show that these Fredholm determinants with kernels of the general form
described above are expressible in terms of solutions of systems of PDE's as
long as phi and psi satisfy a certain type of differentiation formula. There is
also an exponential variant of this analysis which includes the circular
ensembles of NxN unitary matrices.Comment: 34 pages, LaTeX using RevTeX 3.0 macros; last version changes only
the abstract and decreases length of typeset versio
Entanglement between motional states of a single trapped ion and light
We propose a generation method of Bell-type states involving light and the
vibrational motion of a single trapped ion. The trap itself is supposed to be
placed inside a high- cavity sustaining a single mode, quantized
electromagnetic field. Entangled light-motional states may be readily generated
if a conditional measurement of the ion's internal electronic state is made
after an appropriate interaction time and a suitable preparation of the initial
state. We show that all four Bell states may be generated using different
motional sidebands (either blue or red), as well as adequate ionic relative
phases.Comment: 4 pages, LaTe
Successful demonstration of assisted gene flow in the threatened coral <i>Acropora palmata</i> across genetically-isolated Caribbean populations using cryopreserved sperm
Myers' type theorems and some related oscillation results
In this paper we study the behavior of solutions of a second order
differential equation. The existence of a zero and its localization allow us to
get some compactness results. In particular we obtain a Myers' type theorem
even in the presence of an amount of negative curvature. The technique we use
also applies to the study of spectral properties of Schroedinger operators on
complete manifolds.Comment: 16 page
A Vector Non-abelian Chern-Simons Duality
Abelian Chern-Simons gauge theory is known to possess a `-self-dual'
action where its coupling constant is inverted {\it i.e.} . Here a vector non-abelian duality is found in the
pure non-abelian Chern-Simons action at the classical level. The dimensional
reduction of the dual Chern-Simons action to two-dimensions constitutes a dual
Wess-Zumino-Witten action already given in the literature.Comment: 14+1 pages, LaTeX file, no figures, version to appear in Phys. Rev
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