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 $S_n$ and {\it split} bases adapted to the $S_{n_1} \times S_{n_2} \subset S_n$ subgroup ($n_1 +n_2 = n$) 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 $[4,3,2,1]$ of $S_{10}$ into $[3,2,1] \otimes [3,1]$ of $S_6 \times S_4$, 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