http://nopr.niscair.res.in/handle/123456789/14206 Search the Channel search http://nopr.niscair.res.in/simple-search http://nopr.niscair.res.in/handle/123456789/14229 Title: Cold induced aggregation microextraction with an ionic liquid for trace determination of cadmium and lead in water samples <br/> <br/>Authors: Shamsipur, Mojtaba; Ramezani, Majid; Beigi, Ali Akbar Miran; Poursaberi, Tahereh <br/> <br/>Abstract: Cold induced aggregation microextraction (CIAME) with an ionic liquid has been used as a rapid and simple method for determination of trace amounts of cadmium and lead by sequential analysis with flame atomic absorption spectrometry. In this study, cadmium and lead have been complexed with O, O-diethyldithiophosphate as chelating agent in a solution containing Triton X-114 and sodium hexafluorophosphate, and then extracted into an ionic liquid. The effect of various parameters on extraction efficiency such as amounts of [C₆MIM][PF₆] and NaPF₆, <i style="">p</i>H of solution, extraction time, temperature and complexing agent concentration have been optimized. Under the optimized conditions, the detection limits are 0.12 µg L^-1 and 1.61µg L^-1, relative standard deviation 2.4 % and 2.7 % and enrichment factor 70 and 67 for cadmium and lead, respectively. The proposed method has been successfully applied for analysis of cadmium and lead in certified reference material and various water samples. <br/> <br/>Page(s): 825-829 http://nopr.niscair.res.in/handle/123456789/14228 Title: Microwave synthesis of polymer coated silver nanoparticles by glucose as reducing agent <br/> <br/>Authors: Pal, Jolly; Deb, Manas Kanti <br/> <br/>Abstract: Silver nanoparticles have been prepared by the reduction of silver nitrate using glucose as reducing agent and polyvinylpyrrolidone as stabilizing agent and characterized by transmission electron microscopy and UV-visible spectroscopy. TEM images show the average size of silver nanoparticles to be 11 nm. Various optimizing parameters such as effects of silver nitrate concentration, glucose concentration and microwave irradiation time are also described. <br/> <br/>Page(s): 821-824 http://nopr.niscair.res.in/handle/123456789/14227 Title: 2,7-Diferrocenyl-3,6-diazaocta-2,6-diene: A highly selective dual fluorescent sensor for Zn²⁺and Ag⁺and electrochemical sensor for Zn²⁺ <br/> <br/>Authors: Dutta, Kaku; Das, Diganta Kumar <br/> <br/>Abstract: 2,7-Diferrocenyl-3,6-diazaocta-2,6-diene (DFDD), obtained by condensation reaction of acetylferrocene and ethylenediamine, exhibits Zn²⁺ ion-induced enhancement of fluorescence intensity and Ag⁺ ion-induced quenching of fluorescence intensity. The Zn²⁺ ion shifts the redox potential of DFDD from +0.660 V ± 0.005 V to + 0.615 ± 0.005 V as observed by cyclic voltammetry and square wave voltammetry. Ca²⁺, Mg²⁺, Mn²⁺, Fe²⁺, Co²⁺, Ni²⁺, Cu²⁺, Cd²⁺, Pb²⁺ and Hg²⁺ have very little effect on fluorescence intensity of DFDD. These metal ions together with Ag⁺ ion have no effect on the electrochemistry of DFDD. Both, fluorescence and UV-visible spectroscopic data show a 1:1 interaction between DFDD and Zn²⁺ with binding constant 75 <i style="">M</i><i style=""></i>^-1. The applicability of DFDD as fluorescence sensor for Zn²⁺ ion has been shown in its estimation in commercial tablets. <br/> <br/>Page(s): 816-820 http://nopr.niscair.res.in/handle/123456789/14226 Title: Intercalation of biologically important iminodiacetatochromium(III) ion in the interlayer of ZnAl-layered double hydroxide <br/> <br/>Authors: Sahu, R; Mohanta, B S; Das, N N <br/> <br/>Abstract: The intercalation of bis-iminodiacetatochromium(III) ion, [Cr(ida)₂]^-,in the interlayer of ZnAl-layered double hydroxide (LDH) through rehydration of ZnAl(O) mixed oxide and its characterization by XRD, TG-DTA, FT-IR and UV-vis-DRS is described. X-ray diffraction studies reveal the increase of basal spacing in the ZnAl-LDH–Cr(ida) hybrid from 7.69 Å to 12.55 Å due to intercalation of [Cr(ida)₂]^-, which is also evident from FT-IR and UV-vis-DR spectra. Thermogravimetric analyses show a marginal increase in the decomposition temperature for the [Cr(ida)₂]^- moiety with exothermic peaks in the LDH–Cr(ida) hybrid, indicating enhanced thermal stability of the [Cr(ida)₂]^- ion in the LDH interlayer. This method may be useful for intercalation of other anionic Cr(III) complexes of biological importance. <br/> <br/>Page(s): 812-815