http://nopr.niscair.res.in/handle/123456789/3359 Search the Channel search http://nopr.niscair.res.in/simple-search http://nopr.niscair.res.in/handle/123456789/3374 Title: Sonophotocatalytic behavior of cerium doped salts of Cu(II), Co(II) and Mn(II) in the degradation of phenol <br/> <br/>Authors: Pankaj; Verma, Mayank <br/> <br/>Abstract: Crystals of CuSO₄.5H₂O, CoCl₂.6H₂O, and MnCl₂.4H₂O doped with CeCl₃ under sonicated and unsonicated conditions have been synthesized. The crystals synthesized under sonicated conditions are different than those synthesized under unsonicated conditions with respect to shape, size, and color. The crystal composition has been estimated by atomic absorption spectrophotometry with graphite furnace and UV-visible spectrophotometer. Higher percentage of Cu(II), Mn(II) and Ce(III) in the crystals synthesized under sonication as compared to the unsonicated crystals may be attributed to the change in the composition of the lattice pattern due to the mechanical impact of ultrasound, whereas such an effect has not been found in the Co(II) salts. Enhanced sonophotocatalytic effect of these crystals on the degradation of phenol under sonic conditions is attributed to the increased number of unpaired electron following free radical mechanism. <br/> <br/>Page(s): 367-371 http://nopr.niscair.res.in/handle/123456789/3373 Title: Oxidative regeneration of carbonyl compounds from oximes by morpholinium chlorochromate: A kinetic and mechanistic study <br/> <br/>Authors: Choudhary, Anurag; Agarwal, S; Sharma, Vinita <br/> <br/>Abstract: The oxidative deoximination of several aldo- and keto-oximes by morpholinium chlorochromate in dimethyl sulphoxide, exhibits a first order dependence on both the oxime and MCC. The oxidation of ketoximes is slower than that of aldoximes. The rate of oxidation of aldoximes correlate well in terms of Pavelich- Taft dual substituent-parameter equation. The low positive value of polar reaction constant indicates a nucleophilic attack by a chromate oxygen on the carbon. The reaction is subject to steric hindrance by the alkyl groups. The reaction of acetaldoxime has been studied in nineteen different organic solvents. The solvent effect has been analysed by multiparametric equations. A mechanism involving the formation of a cyclic intermediate in the rate-determining step has been proposed. <br/> <br/>Page(s): 362-366 http://nopr.niscair.res.in/handle/123456789/3372 Title: Oxidation of thiosulphate by hexacyanoferrate(III) in aqueous perchloric acid medium — A kinetic and mechanistic study <br/> <br/>Authors: Patil, R K; Chimatadar, S A; Nandibewoor, S T <br/> <br/>Abstract: The kinetics of oxidation of thiosulphate by hexacyano-ferrate(III) in an aqueous perchloric acid medium has been studied spectrophotometrically by stopped flow method at 25°C. The stoichiometry is 1:1, i. e., one mole of thiosulphate consumes one mole of hexacyanoferrate(III). The reaction products are identified as Fe(CN)₆²⁻ and S₄O₆²⁻. The reaction is first order with respect to hexacyanoferrate(III) and thiosulphate concentrations. Increase in perchloric acid concentration increases the rate of reaction (order=0.40). Added products do not have any significant effect on the rate of reaction. The effect of ionic strength and dielectric constants on the reaction rate has also been studied. The active species of oxidant is indicated to be HFe(CN)₆³⁻. A suitable mechanism is proposed and the reaction constants of the different steps involved have been evaluated. Activation parameters have also been calculated with respect to the slow step of the mechanism. <br/> <br/>Page(s): 357-361 http://nopr.niscair.res.in/handle/123456789/3371 Title: Surface functionalities of nitric acid treated carbon – A density functional theory based vibrational analysis <br/> <br/>Authors: Mahalakshmy, R; Indraneel, P; Viswanathan, B <br/> <br/>Abstract: The appropriate combination of surface functionalities and their relative contribution to the total surface functionalities of oxidized carbon by nitric acid are evaluated by density functional theory calculations. Though the computed and experimental spec-tra do not exactly match in all respects, the methodology adopted has a definite role in understanding the complex surface function-alities of treated carbon. <br/> <br/>Page(s): 352-356