Decadal analysis of the flatfish fishery of India

Decadal analysis of the flatfish fishery of Indi

Very low thermal conductivity in lanthanum phosphate-zirconia ceramic nanocomposites processed using a precipitation-peptization synthetic approach

A wet chemical synthetic approach involving precipitation-peptization mechanisms was successfully adopted for the development of LaPO4-ZrO2 nanocomposites with the ZrO2 content varying in the 5-20 wt% range. Stoichiometric lanthanum phosphate, formed as nanofibrils during the precipitation reaction with orthophosphoric acid, was subsequently transformed into nanorods of ~10 nm width and <100 nm length upon peptization at pH 2. Zirconia dispersions were homogeneously incorporated as ultrafine particulates through zirconium oxychloride hydrolysis using ammonia. The nanocomposite precursor thus obtained could be densified to >98% TD for the LaPO4-10 wt% ZrO2 composition upon sintering at 1600 °C. The addition of ZrO2 to LaPO4 impeded densification and grain growth inhibition of up to 50% was obtained for LaPO4-20 wt% ZrO2 nanocomposites. Furthermore, the nanocomposites indicated very low thermal conductivity values (1 W m-1 K-1) compared to single phase LaPO4. The non-reactivity of LaPO4 and ZrO2 at high temperatures and the low thermal conductivity values of LaPO4-ZrO2 render them effective for high temperature thermal insulation applications. © 2016 The Royal Society of Chemistry and the Centre National de la Recherche Scientifique

A facile one pot synthetic approach for C3N4-ZnS composite interfaces as heterojunctions for sunlight-induced multifunctional photocatalytic applications

Herein, we report a facile one pot synthetic protocol for the creation of C3N4-ZnS composite interfaces by the co-pyrolysis of a precursor mix containing zinc nitrate, melamine, and thiourea at 550°C in air. The organic-inorganic semiconductor heterojunctions thus formed displayed increased absorbance in the longer wavelength region and facilitated broad absorption of visible light compared to pure ZnS, C3N4 and conventionally synthesized hybrid samples. The decreased emission intensity, increased photocurrent generation and decreased fluorescence lifetime revealed reduced exciton recombinations in the co-pyrolysed sample containing C3N4-ZnS heterostructures. The samples displayed sunlight driven photocatalytic reduction of nitrophenol as well as hydrogen generation (4 mmol g-1 h-1) by water splitting. © The Royal Society of Chemistry 2016

Tagging of Explosives for Detection

This paper gives the results of a study on estimation of shelf life of2,3-dimethyI2,3-dinitrobutane (DMNB)-tagged RDX and PETN expiosives by monitoring DMNB depletion by high performanceliquid chromatography and simultaneously recording the detectability of the tagged explosive composition using explosive vapoUf detector Model-97 HS. DMNB was incorporated in the explosive using methanol as solvent for DMNB and the explosive compositions were stored at 35,55 and 75 °C over a long period. Methods developed for preparing the homogeneously tagged composition with DMNB at 0.5 per cent level and for the analysis ofDMNB for ensuring homogeneity of DMNB in the composition are described. The results show no change in compatibility and sensitivity on the incorporation of DMNB in the explosive. Estimation of shelf life of DMNB in the explosive was done for a period of storage of 202-304 days at different temperatures

Giant sized rays landed at Cochin Fisheries Harbour

On 4th March 2017, three huge rays - two Mobula tarpacana and one Manta birostris were landed at Cochin Fisheries Harbour. They were caught in long lines, which were operated for skipjack tuna. These rays caught off Ratnagiri coast at a depth of 500m weighed around 400 kg each. Of these, Mobula tarpacana locally called 'Kakkathirandi' measured 2.4 m in disc width (DW)

Magnetism and superconductivity driven by identical 4ff states in a heavy-fermion metal

The apparently inimical relationship between magnetism and superconductivity has come under increasing scrutiny in a wide range of material classes, where the free energy landscape conspires to bring them in close proximity to each other. This is particularly the case when these phases microscopically interpenetrate, though the manner in which this can be accomplished remains to be fully comprehended. Here, we present combined measurements of elastic neutron scattering, magnetotransport, and heat capacity on a prototypical heavy fermion system, in which antiferromagnetism and superconductivity are observed. Monitoring the response of these states to the presence of the other, as well as to external thermal and magnetic perturbations, points to the possibility that they emerge from different parts of the Fermi surface. This enables a single 4$f$ state to be both localized and itinerant, thus accounting for the coexistence of magnetism and superconductivity.Comment: 4 pages, 4 figure

Status of marine fish stock assessment in India and development of a sustainability index

India has a coastline of 8129 km. Landings by commercial fishing vessels takes place at 1332 centres during day and night by 58,911 mechanized craft, 75,591 motorized (with outboard engine) and 104,270 traditional craft (CMFRI, 2006). Marine fisheries are an important source of food, employment and foreign exchange. About one million people work directly in this sector, producing 3 million tonnes annually valued at about 3 billion US $at production level (CMFRI, 2007). India earns 1.6 billion US$ by exporting fish and fishery products. India is among the top ten fish producing countries of the world, contributing 3.5% to the total world marine fish production. Concerned about the status of marine fish stocks in the Indian EEZ, the country has put in place appropriate institutional mechanisms to monitor and forecast fishery yields for the last 25 year