NISCAIR Online Periodicals Repository Collection: IJCT Vol.17(5) [September 2010]

Voltammetric ultra trace level determination of gallium

Sun, 29 Aug 2010 22:58:59 GMT

Title: Voltammetric ultra trace level determination of gallium

Authors: Sharma, P; Dubey, S

Abstract: The optimum conditions for the determination of sub µg level gallium have been developed employing differential pulse polarography. A detection limit of 0.01 g/mL has been achieved. Zinc and indium did not interfere.

Page(s): 396-399

Visible light-driven photocatalytic degradation and mineralization of neutral red dye in a slurry photoreacter

Sun, 29 Aug 2010 22:58:59 GMT

Title: Visible light-driven photocatalytic degradation and mineralization of neutral red dye in a slurry photoreacter

Authors: Pare, Brijesh; Singh, Pardeep; Jonnalagadda, S B

Abstract: Hydroxyl radicals (OH^.) induced photocatalytic degradation of neutral red was investigated in a batch slurry reactor, in the presence of visible light illuminated ZnO. The effects of process parameters such as catalyst loading, initial substrate concentration, Fenton reagent, temperature, solar light and oxidant, and anion concentration were investigated. In the presence of visible light, ZnO/Fenton process was found to be most efficient for the decolorization of dye. Both artificial visible radiation and solar light degraded dye efficiently in the presence of ZnO. The destruction of chromophoric part and aromatic skelton of dye were ascertained by the disappearance of absorption bands in UV/Vis spectra of dye with respect to irradiation time. Complete COD reduction was observed in 8 h of irradiation time. CO₂ and NO₃^- ionswere identified as final mineralization products.

Page(s): 391-395

A new method for the spectrophotometric determination of fexofenadine hydrochloride

Sun, 29 Aug 2010 22:58:59 GMT

Title: A new method for the spectrophotometric determination of fexofenadine hydrochloride

Authors: Narayana, B; Veena, K

Abstract: A novel, sensitive and selective reaction has been proposed for the assay of fexofenadine hydrochloride (FFH) in bulk and dosage forms using chloramine-T (CAT) and two dyes malachite green (MAG) and xylene cyanol FF (XFF). Spectrophotometric method entail the addition of a known excess of chloramine-T to fexofenadine hydrochloride in hydrochloric acid medium followed by the determination of residual oxidant by reacting it with a fixed amount of malachite green, measuring the absorbance at 615 nm (method A), or xylene cyanol FF, measuring the absorbance at 612 nm (method B). The apparent molar absorptivities are calculated to be 4.09×10⁴ L mol^-1 cm^-1, 3.07×10⁴ L mol^-1 cm^-1for method A and B respectively. Both methods are of comparable accuracy and precision. There is no interference from common additives and excipients. The method has been applied to the determination of fexofenadine hydrochloride in pharmaceutical samples and the results are statistically compared with those of literature UV-spectrophotometric method by applying student’s t-test and F-test.

Page(s): 386-390

Electrolytic deposition of Zn-Mn-Mo alloys from a citrate bath

Sun, 29 Aug 2010 22:58:59 GMT

Title: Electrolytic deposition of Zn-Mn-Mo alloys from a citrate bath

Authors: Rastogi, Renu; Pandey, Archana

Abstract: Zn-Mn-Mo alloys were electrodeposited from a citrate bath and the influence of various parameters such as current density, 2.0-6.0 Adm^-2; temperature, 20-35ºC; pH, 2.0-2.15; duration of deposition 20-50 min and concentration of the constituent metals were studied. The electrolytic bath consists of zinc sulphate (20-35 gL^-1), manganese sulphate (50-80 gL^-1), ammonium molybdate (3-6 gL^-1), citric acid (5 gL^-1) and starch (1 gL^-1). Semi bright, light gray adherent deposits were generally obtained containing 88.98-99.82% Zn, 0.06-8.70% Mn and 0.10-2.32% Mo. The variation of cathode polarization with current density or the pH under the conditions was studied. Morphological studies have also been done.

Page(s): 381-385