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Reservoirs and barrages , built across alluvial rivers throughout the world, are losing their storage capacity at an estimated rate of about 1% annually. The pond area of Durgapur Barrage on River Damodar, India, controlled by barrage-gates is no exception. In spite of its service for more than 60 years through judicious gate-operation schedule, it is found that 52% of initial storage capacity Pond has been lost since its inception in 1956. A morphodynamic study of the alluvial Damodar River, extending from Maithon and Panchet dams at upstream to Durgapur Barrage in the downstream, has been done using a numerical model of MIKE-11. Hydrometeorological data of Damodar-Barakar River basin were used to simulate hydrodynamic and sediment transport models for ascertaining annual rate of erosion and deposition during the period 1956–2016. Study shows that about 6 million M3 sediment were transported from catchment through Dam-discharge, a part of which got deposited in the river bed while the remaining 4.9 million M3 washed away downstream through Barrage gates. Although the rate of deposition in the pond area was initially higher during the period 1956–1985, which has subsequently reduced. However, daily deposition increased more or less linearly with the increase in discharge of the river. [ABSTRACT FROM AUTHOR]

An ion chromatography method was developed for the simultaneous determination of fluoride, iodate and iodide in a caustic scrubber solution used for trapping off-gases released during the dissolution of nuclear fuels. A separation between iodate and fluoride could be realized with 0.6 mM hydroxide, which is too weak to elute other anions including iodide in reasonable time. Studies were carried out at different column temperature, and with the help of Van't Hoff plots the thermodynamic parameters associated with the column equilibrium were estimated, which helped in understanding the co-elution of iodate and fluoride at higher concentration of eluent. An arrangement of conductivity detector and UV-VIS detector in sequence after the ion exchange column (with 15 mM NaOH as eluent) was used for recording chromatograms for conductivity signal and UV-VIS signal simultaneously. The information from the two chromatograms was utilized to quantify iodate, fluoride and iodide in a single run. The limit of detection for fluoride, iodate and iodide is 7 ppb, 10 ppb and 12 ppb, respectively. The precision of the method is better than 2% (RSD) at 0.5 mg/L. The method was used successfully for the real sample analysis. [ABSTRACT FROM AUTHOR]

The present study reports the occurrence of Gold spotted grenadier anchovy Coilia dussumieri Valenciennes, 1848 for the first time from the Andaman and Nicobar Islands, India based on three specimens (Standard length = 124.3 - 134.7 mm) collected from Junglighat fish landing Centre, Port Blair. Description of the species has been provided herewith along with the morphometric measurements and meristic characters. Only one species of the genus Coilia (Coilia ramcarati Hamilton 1820) was known from Andaman and Nicobar Islands earlier and the present report adds a new record to the ichthyofaunal list of Andaman and Nicobar Islands, India. [ABSTRACT FROM AUTHOR]

The role of co-doping with Ba and Sm in Bi and Fe sites of BiFeO3 (BFO), respectively, on the structural and multiferroic properties has been studied in this investigation. Multiferroic ceramics Bi0.85Ba0.15Fe1−xSmxO3 (BBFSO) with x = 0, 0.02, 0.05, and 0.07 have been synthesized by using the standard solid-state reaction method. The Structural depiction and surface morphology are accomplished by X-ray diffraction (XRD) and Scanning Electron Microscope (SEM), respectively. Analysis of the XRD pattern reveals that the structural phase is found pseudo-cubic with the substitution of Ba and Sm for all the samples. Microstructural investigation shows that the samples possess fine crystalline structure and the estimated grain size decreases with the increase in Sm content. The electromagnetic properties such as complex initial permeability, relative quality factor, dielectric constant, dielectric loss, and ac conductivity have been measured by Wayne Kerr Impedance Analyzer. It is found that co-doped samples have improved dielectric property. The sample having 2% Sm exhibits the highest dielectric constant and lowest loss in the dispersive region. Enhanced electric polarization is found for co-doped samples, which might be due to the reduction in leakage current. From impedance spectroscopy analysis, it is observed that only grain boundary is responsible for the conduction process and the electric modulus confirms the existence of electronic relaxation. The real part of initial permeability and relative quality factor increase significantly with Sm doping. The magnetic hysteresis loops confirm that Sm doping notably increases the coercivity of the Bi0.85Ba0.15FeO3 ceramics. The coexistence of ferroelectricity and ferromagnetism in BBFSO as is evident from the P–E and M–H loops can be used for fabricating magnetoelectric devices. [ABSTRACT FROM AUTHOR]