790 research outputs found
Hydrology of the Korapuzha estuary, Malabar, Kerala State
A preliminary enquiry on the hydrological and planktological conditions in the
river mouth region was conducted during the period 1950-52 and the results published
in an abstract form (George, 1953a). This study was later extended to
cover the 25 Ian seaward region of the estuary in 1954. As is well known, the
Malabar coast is highly productive from the fisheries point of view and it was
also observed that the sea waters of the inshore region off Calicut are rich in plankton
and nutrient salts (George, 1953b). Results of the present investigation would
therefore serve to assess the influence of land drainage in the enrichment and replenishment
of the coastal waters and allied factors
Preparation of Electronics grade Bismuth, Antimony, Tellurium, Cadmium and Zinc by Vaccum distillation and Zone refining
APART from the usual importance of bismuth, antimony, tellurium, cadmium & zinc in thechemical, metallurgical, cosmetic, pharmaceutical and paint industries , these materials in their high purity forms (9999 to 99999 %) have recently acquired special significance in the electronics industry for semiconductor and various other applications. The major applications of these electronics grade materials in the electronic industry are :
Bismuth : solders and thermo-electric devices,
Antimony : semi-conductor devices + for crystal doping),
photocell cathodes,
Tellurium Compound semi-conductors
Cadmium Solders mostly for semi-conductor processing
and for compound semi-conductors, such as CdS.
Zinc : dopant and diffusant in semi-conductors
Impact of recent cyclone on the marine fishery sector along the east Godavari and Visakhapatnam districts of Andhra Pradesh
A cyclone which lashed along the coastal Andhra Pradesh on the night of 6-11-'96 resulted in the loss of thousands of human lives and materials. The coast of East Godavari and parts of Visakhapatnam districts were the worst hit areas with high velocity winds bringing in huge tidal waves which inundated the fish landing centres
Asymptotics for numbers of line segments and lines in a square grid
We present an asymptotic formula for the number of line segments connecting
q+1 points of an nxn square grid, and a sharper formula, assuming the Riemann
hypothesis. We also present asymptotic formulas for the number of lines through
at least q points and, respectively, through exactly q points of the grid. The
well-known case q=2 is so generalized
At the horizon of a supersymmetric AdS_5 black hole: Isometries and half-BPS giants
The near-horizon geometry of an asymptotically AdS_5 supersymmetric black
hole discovered by Gutowski and Reall is analysed. After lifting the solution
to 10 dimensions, we explicitly solve the Killing spinor equations in both
Poincare and global coordinates. It is found that exactly four supersymmetries
are preserved which is twice the number for the full black hole. The full set
of isometries is constructed and the isometry supergroup is shown to be
SU(1,1|1) X SU(2) X U(3). We further study half-BPS configurations of D3-branes
in the near-horizon geometry in Poincare and global coordinates. Both giant
graviton probes and dual giant graviton probes are found.Comment: 26 pages. v2:Typos corrected, minor change
Open-String Actions and Noncommutativity Beyond the Large-B Limit
In the limit of large, constant B-field (the ``Seiberg-Witten limit''), the
derivative expansion for open-superstring effective actions is naturally
expressed in terms of the symmetric products *n. Here, we investigate
corrections around the large-B limit, for Chern-Simons couplings on the brane
and to quadratic order in gauge fields. We perform a boundary-state computation
in the commutative theory, and compare it with the corresponding computation on
the noncommutative side. These results are then used to examine the possible
role of Wilson lines beyond the Seiberg-Witten limit. To quadratic order in
fields, the entire tree-level amplitude is described by a metric-dependent
deformation of the *2 product, which can be interpreted in terms of a deformed
(non-associative) version of the Moyal * product.Comment: 30 pages, harvma
A reduced subduction graph and higher multiplicity in S_n transformation coefficients
Transformation coefficients between {\it standard} bases for irreducible
representations of the symmetric group and {\it split} bases adapted to
the subgroup () are
considered. We first provide a \emph{selection rule} and an \emph{identity
rule} for the subduction coefficients which allow to decrease the number of
unknowns and equations arising from the linear method by Pan and Chen. Then,
using the {\it reduced subduction graph} approach, we may look at higher
multiplicity instances. As a significant example, an orthonormalized solution
for the first multiplicity-three case, which occurs in the decomposition of the
irreducible representation of into
of , is presented and discussed.Comment: 12 pages, 1 figure, iopart class, Revisited version (several
typographical errors have been corrected). Accepted for publication in J.
Phys. A: Math. Ge
Extremal single-charge small black holes: Entropy function analysis
We study stretched horizons of the type AdS_2 x S^8 for certain spherically
symmetric extremal small black holes in type IIA carrying only D0-brane charge
making use of Sen's entropy function formalism for higher derivative gravity. A
scaling argument is given to show that the entropy of this class of black holes
for large charge behaves as \sqrt{|q|} where q is the electric charge. The
leading order result arises from IIA string loop corrections. We find that for
solutions to exist the force on a probe D0-brane has to vanish and we prove
that this feature persists to all higher derivative orders. We comment on the
nature of the extremum of these solutions and on the sub-leading corrections to
the entropy. The entropy of other small black holes related by dualities to our
case is also discussed.Comment: 19 pages, v2:typos corrected and references adde
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