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A novel microextraction method termed ionic liquid-based submerged single drop microextraction combining liquid chromatography (LC) was developed for the determination of aromatic amines in environmental water samples. This method is simple and rapid for the determination of three aromatic amines (2-nitroaniline, 3-chloroaniline and 4-bromoaniline) which were selected as model compounds for validation of this new mode of microextraction. This technique combines extraction and preconcentration of the analytes in one step before determination by LC-UV, and the ionic liquid was used instead of the organic solvent as extractant. Several important parameters influencing the extraction efficiency such as the volume of the aqueous sample solution (donor phase), extraction time, pH of the donor phase and salt effect were investigated. Under the optimized conditions, acceptable enrichment factors (132-186) and relative recoveries (82-98%) were obtained for the extraction of the target analytes in real water samples. The calibration curves were linear with correlation coefficients ranging from 0.9983 to 0.9989 and RSDs (n = 5) of 4.9-6.8%. The LODs for the three aromatic amines were 1-2.5 μg L-1 at a signal-to-noise ratio (S/N) of 3. © 2010 Vieweg+Teubner Verlag | Springer Fachmedien Wiesbaden GmbH. Source


Zamani H.A.,Islamic Azad University at Quchan
Chinese Chemical Letters | Year: 2011

In this study, a new Er3+ sensor based on N- (benzyloxycarbonyloxy)succinimide (BCS) as a neutral carrier has been constructed. The sensor exhibits potential linear response with a Nernstian slope of 20.5 ± 0.4 mV/decade in the concentration range of 1.0 × 10-6 to 1.0 × 10-2 mol/L of Er3+. It has a very short response time (<10 s), detection limit of 6.3 × 10 -7 mol/L and a good selectivity relative to a wide variety of other metal ions including common alkali, alkaline earth, heavy, and transition metal ions. It can be used in the pH range of 2.5-10.6 without any considerable divergence in potentials. The proposed sensor was successfully applied for the recovery of Er3+ ions spiked in tap and river water samples. © 2010 Hassan Ali Zamani. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved. Source


N1,N2-Bis[1-(2-hydroxyphenyl)methylidene] ethanedihydrazide (MEH) was used as new compound which plays the role of an excellent ion carrier in the fabrication of a Ho(III) membrane electrode. The electrode shows a good selectivity for Ho(III) ion with respect to most common cations including alkali, alkaline earth, transition and heavy metal ions. This electrode has a wide linear dynamic range from 1.0 × 10-6 to 1.0 × 10-2 mol/L with a Nernstian slope of 19.8 ± 0.3 mV per decade and a low detection limit of 5.8 × 10-7 mol/L in the pH range of 2.5-9.8, while the response time was rapid (<10 s). The suggested sensor was applied to the determination of Ho(III) ions in tap water and river water samples. © 2010 Hassan Ali Zamani. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved. Source


Mohadeszadeh M.,Islamic Azad University at Quchan
Journal of Cluster Science | Year: 2011

A supramolecular tungstoarsenate(V) containing UO2 2+ cations has been isolated by reaction of the ammonium salt of lacunary sandwich-type anion [As2W18(UO2)2O68]14- in aqueous solution of CeIV (pH 3. 5). The product prepared as NH4 + salt, (NH4)18[(NH4)12(UO2(H2O))6(UO2(μ2-H2O)6(α-AsW9O34)6]·74H2O (I), have been characterized by single crystal X-ray diffraction, elemental analysis, IR, and UV/vis spectroscopy. The anion consists on six lacunary α-AsW9O34 9- anions linked by twelve UO2 2+ cations which resembles a star (six-member). The single crystal structure of I reveals two types uranium atoms; six uranium atoms in the central of anion form two U3O3 trigonal bridging groups in which each uranium atom bounds to three oxygen atoms of one AsW9 and two bridging water ligands. The other uranium atoms form two equatorial bonds to one AsW9 and two equatorial bonds to two other AsW9 fragments. The UV/vis spectroscopy confirms the strong coordination of oxygen atoms of α-AsW9O34 9- anions to uranyl cations in the equatorial plane. © 2011 Springer Science+Business Media, LLC. Source


Zamani H.A.,Islamic Azad University at Quchan
E-Journal of Chemistry | Year: 2012

A new coated wire electrode (CWE) using 5-(methylsulfanyl)-3- phenyl-1H-1,2,4-triazole (MPT) as an ionophore has been developed as a neodymium ion-selective sensor. The sensor exhibits Nernstian response for the Nd 3+ ions in the concentration range of 1.0×10 -6-1.0×10 -2 M with detection limit of 3.7×10 -7 M. It displays a Nernstian slope of 20.2±0.2 mV/decade in the pH range of 2.7-8.1. The proposed sensor also exhibits a fast response time of ∼5 s. The sensor revealed high selectivity with respect to all common alkali, alkaline earth, transition and heavy metal ions, including members of the lanthanide family other than Nd 3+. The electrode was used as an indicator electrode in the potentiometric titration of Nd(III) ions with EDTA. The electrode was also employed for the determination of the Nd3+ ions concentration in water solution samples. Source

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