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  • Author or Editor: N. Das x
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Abstract  

Liquid-liquid extractions of zirconium(IV) from aqueous HCl solutions by mixtures of Aliquat 336 or Alamine 336 and diocytl sulfoxide (DOSO) in the diluent benzene has been found to be always higher than that by any single extractant. While the cationic extractants extract Zr(IV) above 6M HCl, DOSO extracts from 4M onwards. Synergism has been observed in all cases. With any of these extractants extraction becomes almost quantitative at and above 10M HCl, but with mixtures of the cationic and neutral extractants, extraction is quantitative in the range 8–9M HCl. Although the extracted species with DOSO alone seems to be ZrCl4·DOSO, with the mixture of extractants, however, the extracted species appear to be Q2ZrCl6·DOSO where Q is R3 +NH (for Alamine 336) and R3 +N(CH3) (for Aliquat 336). Studies on separation of95Zr–95Nb pair from aqueous HCl media by Alamine 336 or DOSO and their mixtures in benzene exhibit preferential extraction of95Nb leaving behind95Zr in the aqueous phase, and extractions have been found to depend both upon the extractant and HCl concentrations.

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Abstract

A new CrIII–Schiff base complex of N,N′-ethylene-bis-salicylamide (Salm), supported on acidic alumina, was characterized by chemical and spectral (UV–Vis-DRS and FT-IR) analyses. The comparative catalytic activity of the neat and supported metal complex was evaluated using H2O2 decomposition as the model reaction at varying H2O2 concentration and amount of catalyst which showed a higher activity for the supported metal complex. A preliminary study showed that the supported CrIII(Salm) was also active for the oxidation of phenol using H2O2 as oxidant leading to catechol (selectivity ∼62%) and hydroquinone (selectivity ∼32%) as the major products.

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One thousand four hundred and eighty three spring wheat germplasm (Triticum aestivum L.) lines comprising Indian as well as exotic lines were screened for resistance to spot blotch disease during winter 2014-15 at hot spot locations i.e., Banaras Hindu University, Varanasi and Uttar Banga Krishi Vishwavidyalaya, Cooch Behar. Severity of the disease at different stages beginning from tillering to dough stage was recorded. Location Severity Index (LSI) of Varanasi was higher than Cooch Behar. Twenty eight accessions were resistant or highly resistant at both locations. These 28 accessions were validated during the winter season (2015–2016). These germplasm were also evaluated at four environments for agronomic traits. Out of 28 accessions, seven (IC564121, IC529684, IC443669, IC443652, IC529962, IC548325 and EC178071-331) were highly resistant across the locations and over the years of study. These accessions comprised one exotic and six indigenous accessions belonging to Uttarakhand and Haryana. Two lines (IC529962 and IC443652) had higher yield than the best check at all the locations. These lines showing highly resistant reaction alongwith wider adaptability can be expedited for direct cultivation or for the development of high yielding and disease resistant cultivars. These lines can also be used for identification of novel resistance gene using allele mining tools and their deployment for the development of spot blotch resistant cultivars.

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