Synthesis & Characterization of Some Complexes of Antimony(III) with Polyhydric Phenols, Acid Amides & Indene

689-69

Nitro & Nitrito Derivatives of Dicyclopentadienyl & Bisindenyl Tungsten(VI) Oxychlorides

622-62

Some Novel Di- & Tetra-cyclopentadienyl-tungsten(VI) & Di- & Tetra-Indenyl-tungsten(VI) Oxides & Sulphides

150-15

Dicarboxylato & Salicylato Chelates of Oxotungsten(VI)

912-91

Correlation of IR Data with the Stability of Pt(IV), Ir(III), Rh(III), Ru(III), Co(III), Cr(III), Ni(II), Pt(IV), Pd(II) & Cu(II) Complexes of 3.3'-Diamino-4,4'-dihydroxydiphenyl Sulphone

813-81

Co-axial dual-core resonant leaky fibre for optical amplifiers

We present a co-axial dual-core resonant leaky optical fibre design, in which the outer core is made highly leaky. A suitable choice of parameters can enable us to resonantly couple power from the inner core to the outer core. In a large-core fibre, such a resonant coupling can considerably increase the differential leakage loss between the fundamental and the higher order modes and can result in effective single-mode operation. In a small-core single-mode fibre, such a coupling can lead to sharp increase in the wavelength dependent leakage loss near the resonant wavelength and can be utilized for the suppression of amplified spontaneous emission and thereby gain equalization of an optical amplifier. We study the propagation characteristics of the fibre using the transfer matrix method and present an example of each, the large-mode-area design for high power amplifiers and the wavelength tunable leakage loss design for inherent gain equalization of optical amplifiers.Comment: 6 page

Simulated Model Studies on the Beneficiation of Calcareous Phosphate Ore

The main sources of rock phosphate are located in Rajasthan, Mussoorie (U.P.), Singhbhum (Bihar), Purulia (W.B.) etc. Phosphate rocks generally occur as calcitic, siliceous and ferruginous in nature. Rajasthan and Muss-oorie rocks are calcareous (CaO 40-50%). Hence to enrich the phosphate in the rock from average 16-20% to above 30% P205 two possible alternatives to beneficiate this ore

Birefringence analysis of multilayer leaky cladding optical fibre

We analyse a multilayer leaky cladding (MLC) fibre using the finite element method and study the effect of the MLC on the bending loss and birefringence of two types of structures: (i) a circular core large-mode-area structure and (ii) an elliptical-small-core structure. In a large-mode-area structure, we verify that the multilayer leaky cladding strongly discriminates against higher order modes to achieve single-mode operation, the fibre shows negligible birefringence, and the bending loss of the fibre is low for bending radii larger than 10 cm. In the elliptical-small-core structure we show that the MLC reduces the birefringence of the fibre. This prevents the structure from becoming birefringent in case of any departures from circular geometry. The study should be useful in the designs of MLC fibres for various applications including high power amplifiers, gain flattening of fibre amplifiers and dispersion compensation.Comment: 18 page

Substituted Thiobiurets as Corrosion Inhibitors for Mild Steel in L.ON Sulphuric Acid

Corrosion inhibition studies of mild steel in 1.ON sulphuric acid have been performed at 25°C using substituted thiobiurets as inhibitors. All the inhibit- ors were found to inhibit the process by getting adsorbed on the metal surface. A comparative account of inhibition efficiencies of different compounds has been given consi-dering their size and probable sites through which adsor-ption can take place. Among the studied thiobiurets methoxyphenyl derivative behaved as the best corrosion inhibitor followed by mefhylphenyl-, phenyl- and chlorophenyl-derivatives