http://nopr.niscpr.res.in/handle/123456789/20973 Fri, 09 Oct 2026 06:49:41 GMT 2026-10-09T06:49:41Z http://nopr.niscpr.res.in/handle/123456789/21064 Title: Separation and determination of 3,4-dimethoxybenzaldehyde and related compounds by high performance capillary electrophoresis Authors: Sekar, R; Kulshrestha, U C; Vairamani, M Abstract: 3,4-Dimethoxybenzaldehyde and five related compounds have been separated and determined by high performance capillary electrophoresis using micellar electrokinetic chromatography method. Good separation for all the compounds is achieved using 10 m<i>M </i>di-sodium tetraborate, 100 m<i>M </i>sodium dodecyl sulphate and 10% acetonitrile. The detection has been carried out at 214 nm using UV-vis detector. The proposed method has been further applied for the quality control of two commercial samples. Page(s): 662-665 Fri, 01 Jun 2001 00:00:00 GMT http://nopr.niscpr.res.in/handle/123456789/21064 2001-06-01T00:00:00Z http://nopr.niscpr.res.in/handle/123456789/21063 Title: Spectrophotometric determination of chromium(VI) in soil and steel samples using methdilazine hydrochloride^† Authors: Melwanki, M B; Seetharamappa, J Abstract: Methdilazine hydrochloride has been used as a sensitive and selective reagent for the rapid spectrophotometric determination of chromium(VI). The reagent gives a red coloured species instantaneously on reaction with chromium(VI) in phosphoric acid medium and exhibits maximum absorbance at 512 nm with Sandell's sensitivity of 3.1ng cm^-2. Beer's law is obeyed over the concentration range of 0.1-1.8 ppm; the optimum concentration range is 0.2-1.6 ppm. The method has been successfully applied to the analysis of chromium(VI) in steels and soil samples. Page(s): 659-661 Fri, 01 Jun 2001 00:00:00 GMT http://nopr.niscpr.res.in/handle/123456789/21063 2001-06-01T00:00:00Z http://nopr.niscpr.res.in/handle/123456789/21062 Title: Spectrophotometric determination of nitrite by the formation of bisazo dye Authors: Gayathri, N; Balasubramanian, N Abstract: A sensitive spectrophotometric method for the determination of nitrogen dioxide in air, nitrate and nitrite in water, soil, radiator coolant and some analytical grade chemicals is described. The method is based on diazo coupling reaction, where 4-amino azobenzene is treated with nitrite under acidic condition in the presence of bromide ion and the formed diazonium salt couples with resorcinol in acid medium. The formed bisazo dye has an absorption maxima at 550 nm under alkaline condition and obeys Beer's law over the range 0-16 μg<i> </i>of nitrite in overall aqueous volume of 25 mL . The system obeys Beer's law over the range 0-3 μg nitrite, when extracted into toluene under ammoniacal condition (<i>p</i>H 9.0 ± 0.5) and stripped to aqueous phase with 5 mL of 0.35 molar NaOH. The molar absorptivity of the colour system is 4.8×10⁴ L. mol^-1 cm^-1. Page(s): 656-658 Fri, 01 Jun 2001 00:00:00 GMT http://nopr.niscpr.res.in/handle/123456789/21062 2001-06-01T00:00:00Z http://nopr.niscpr.res.in/handle/123456789/21061 Title: Synthesis and characterization of some novel mixed-ligand cyanonitrosyl {MnNO}⁶ complexes of manganese(I) involving multifunctional bioactive organic donors Authors: Maurya, R C; Batalia, S Abstract: Novel mixed-ligand cyanonitrosyl complexes of manganese(I), formed by interaction of pentacyanoni trosylmanganate(I) anion,[Mn(NO)(CN)]^3- with 2,3-pyridincdiearboxylic acid (PDA), 7 -chloro-4-(3-diethylaminomethyl-4-hydroxyanilino)quinoline dihydrochloride dihydrate (CDAHQ) and 4,4'-diaminodiphenyl sulphone (DADPS), have been synthesized and characterized by elemental analyses, molar conductances, magnetic and decomposition temperature measurements, infrared and electronic spectral studies. The complexes have the compositions, [Mn(NO)(CN)₂(PDA)₂(H₂O)],Mn(NO)(CN)₂(CDAHQ) (H₂O)₂] and Mn(NO)(CN)₂(DADPS)(H₂O)]₂.Suitable octahedral structures have been proposed for these complexes. Page(s): 652-655 Fri, 01 Jun 2001 00:00:00 GMT http://nopr.niscpr.res.in/handle/123456789/21061 2001-06-01T00:00:00Z