http://nopr.niscair.res.in/handle/123456789/798 Search the Channel search http://nopr.niscair.res.in/simple-search http://nopr.niscair.res.in/handle/123456789/1227 Title: A pulse polarographic method for the analysis of zinc dithiocarbamates <br/> <br/>Authors: Sharma, D K; Kumar, Satish; Chauhan, Chetan; Gupta, Atul <br/> <br/>Abstract: An extremely sensitive pulse polarographic method for the determination of zinc dimethyldithiocarbamate (an agricultural fungicide) and zinc di-n-pentyldithiocarbamate (a petroleum additive), has been developed based on the reaction of their dithiocarbamate moiety with copper(II) perchlorate in acetonitrile medium. Well defined diffusion-controlled peaks are observed at –140 mV and –130 mV (vs SCE) for zinc dimethyldithiocarbamate and zinc di-n-pentyldithiocarbamate respectively. The peaks shows approximately four-fold higher sensitivity than that obtained by pulse polarography of the zinc dithiocarbamate alone. A linear relationship is obtained between concentration of the zinc dithiocarbamate [added to copper(II)] and peak current. Using cyclic voltammetry, a probable mechanism for the zinc dithiocarbamate-copper(II) reaction has been proposed. <br/> <br/>Page(s): 1121-1124 Thu, 28 Jun 2007 22:58:59 GMT http://nopr.niscair.res.in/handle/123456789/1226 Title: Inhibition effect of Brij-35 on the rate of oxidation of ascorbic acid by hexacyanofer-rate(III) in acidic medium: A kinetic study <br/> <br/>Authors: Shukla, Ratna; Upadhyay, Santosh K <br/> <br/>Abstract: The effect of non-ionic surfactant, i.e. Brij-35, polyoxyethyl-ene(23)laurylether, on the rate of oxidation of ascorbic acid by hexacyanoferrate(III) in acidic (HClO4) medium has been studied spectrophotometrically in the temperature range 30-50C. The rate of oxidation is inhibited in presence of Brij-35 even below the critical micelle concentration (CMC) of the surfactant. A mecha-nism of oxidation in presence of the surfactant is proposed and discussed. The binding parameters between the surfactant and ascorbic acid have been evaluated using Menger and Portnoy’s model reported for micellar catalysis/inhibition. <br/> <br/>Page(s): 1116-1120 Thu, 28 Jun 2007 22:58:59 GMT http://nopr.niscair.res.in/handle/123456789/1225 Title: Synthesis and characterization of new complexes formed by insertion of carbon disulphide in RuL₃Cl3 (L=PPh₃ and AsPh₃) <br/> <br/>Authors: Gogoi, Pradip K; Borah, Geetika; Bharali, Nayanmoni; Saikia, Diganta <br/> <br/>Abstract: Reaction of RuL₃Cl₃ (L=PPh₃ and AsPh₃) with stoichiometric amount of CS₂ in ethanol-dichloromethane mixed solvent systems at room temperature yields paramagnetic complexes of the type [RuL₂Cl₂(S₂COEt)].The complexes have been characterized by conductance, IR, electronic, ESR spectral, magnetic moment measurement and thermal data as well as by elemental analysis. The appearance of three g-values in the ESR spectra reveal a highly distorted octahedral environment around ruthenium(III) ion with one bidented EtOCS₂⁻ ligand. <br/> <br/>Page(s): 1113-1115 Thu, 28 Jun 2007 22:58:59 GMT http://nopr.niscair.res.in/handle/123456789/1223 Title: Synthesis, spectroscopic and electrochemical studies of novel transition metal complexes with N,N'-bis(2-hydroxynaphthalin- 1-carbaldehydene)-1,3-bis- (o-aminophenoxy) propane <br/> <br/>Authors: Temel, Hamdi; İlhan, Salih; Aslanoğlu, Mehmet; Alp, Hüseyin <br/> <br/>Abstract: A novel Schiff base obtained by the reaction of 1,3-bis-(o-aminophenoxy)propane and 2-hydroxynaphthalin-1-carbaldehyde, forms complexes with Co(II), Cu(II) and Ni(II). The Schiff base ligand and its metal complexes have been characterized by elemental analysis, microanalytical data, magnetic measurements, UV-visible, ¹H NMR, ¹³C NMR and IR-spectra as well as conductance measurements. Electrochemical data show that NiL and CuL complexes undergo metal based quasi-reversible one-electron redox processes. However, metal complexes also exhibit ligand based irreversible redox waves. The electrochemical results also indicate that the electron transfer rate is higher for NiL complex than the CuL complex. Voltammetric data reveal easier electron donor properties for the NiL complex. <br/> <br/>Page(s): 1109-1112 Thu, 28 Jun 2007 22:58:59 GMT