University of North Florida
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Stuart Chalk, Ph.D.
Department of Chemistry
University of North Florida
Phone: 1-904-620-1938
Fax: 1-904-620-3535
Email: schalk@unf.edu
Website: @unf

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Abaas Afkhami

Abbrev:
Afkhami, A.
Other Names:
Address:
Department of Chemistry, Faculty of Sciences, Bu-Ali Sina University, Hamadan, Iran
Phone:
+98 811 8272404
Fax:
+98 811 8272404

Citations 5

"Kinetic-spectrophotometric Determination Of Trace Amounts Of As(III) Based On Its Inhibitory Effect On The Redox Reaction Between Bromate And Hydrochloric Acid"
Talanta 2001 Volume 55, Issue 1 Pages 55-60
Abbas Afkhami, Tayyebeh Madrakian and Akbar Afshar Assl

Abstract: A simple, sensitive, rapid and reliable method has been developed for spectrophotometric determinations of As(III) in the presence of As(V) based on its inhibition effect on the redox reaction between bromate and hydrochloric acid. The decolorization of methyl orange by the reaction products was used to monitor the reaction spectrophotometrically at 525 nm. The method allows the determination of arsenic in the range of 6-1000 µg L-1. The relative standard deviation for 10 determinations of 40 µg L-1 of As(III) was 1.43% and the limit of detection, corresponding to a signal to noise ratio of three, was 3.4 µg L-1. The proposed method was applied to the determination of As(III) in water samples with satisfactory results. (C) 2001 Elsevier Science BN. All rights reserved.
Speciation

"Indirect Determination Of Sulfide By Cold Vapor Atomic Absorption Spectrometry"
Microchim. Acta 2005 Volume 150, Issue 1 Pages 43-46
Abbas Afkhami and Lida Khalafi

Abstract: A method for the determination of sulfide based on its interference with the determination of Hg by cold vapor atomic absorption spectrometry is described. The decrease in mercury absorbance at 253.7 nm is proportional to the concentration of sulfide over the range of 10^-320 ng mL-1. The limit of detection was found to be 7 ng mL-1 and the relative standard deviation (RSD) for the determination of different concentrations of sulfide was in the range of 1.8-2.2%. This method was applied to the determination of sulfide in whole human blood after gas-phase separation.

"Highly Selective Determination Of Trace Quantities Of Mercury In Water Samples After Preconcentration By The Cloud-point Extraction Method"
Int. J. Environ. Anal. Chem. 2006 Volume 86, Issue 15 Pages 1165-1173
Abbas Afkhami; Tayyebeh Madrakian; Hajar Siampour

Abstract: A cloud-point extraction method for pre-concentration of ultra-trace quantities of mercury ions as a prior step to its determination by spectrophotometry. The method is based on the cloud-point extraction of mercury in iodide media with Triton X-114. The pre-concentrated mercury was then determined spectrophotometrically by measuring the absorbance of the surfactant rich phase at 300 nm and also by cold-vapor atomic absorption spectrometry (CVAAS). Linearity was obeyed in the range of 0.40-40.0 ng mL-1 by CVAAS and in the range of 10.0-400.0 ng mL-1 by spectrophotometry. The detection limit is 3.0 ngmL-1 by spectrophotometry and 0.10 ng mL-1 by CVAAS. The interference effect of several anions and cations was also tested. The method was used to determine mercury in water samples. © 2006 Taylor & Francis.

"Spectrophotometric Determination Of Fluoxetine By Batch And Flow Injection Methods"
Chem. Pharm. Bull. 2006 Volume 54, Issue 12 Pages 1642-1646
Abbas Afkhami, Tayyebeh Madrakian and Lida Khalafi

Abstract: A rapid, simple, and accurate spectrophotometric method is presented for the determination of fluoxetine by batch and flow injection analysis methods. The method is based on fluoxetine competitive complexation reaction with phenolphthalein-?-cyclodextrin (PHP-?-CD) inclusion complex. The increase in the absorbance of the solution at 554 nm by the addition of fluoxetine was measured. The formation constant for fluoxetin-?-CD was calculated by non-linear least squares fitting. Fluoxetine can be determined in the range 7.0 x 10^-6-2.4 x 10^-4 mol L-1 and 5.0 x 10^-5-1.0 x 10^-2 mol L-1 by batch and flow methods, respectively. The limit of detection and limit of quantification were respectively 4.13 x 10^-6 mol L-1 and 1.38 x 10^-5 mol L-1 for batch and 2.46 x 10^-5 mol L-1 and 8.22 x 10^-5 mol L-1 for flow method. The sampling rate in flow injection analysis method was 80 ±5 samples h-1. The method was applied to the determination of fluoxetine in pharmaceutical formulations and after addition to human urine samples. © 2006 Pharmaceutical Society of Japan.

"Kinetic-spectophotometric Determination Of Hydrazine By The Inhibition Of The Bromate-hydrochloric Acid Reaction"
Anal. Chim. Acta 2000 Volume 419, Issue 1 Pages 101-106
Abaas Afkhami and Akbar Afshar-E-Asl

Abstract: A simple, sensitive, accurate and selective method for rapid determination of hydrazine is described which is based on its inhibition effect on the reaction between bromate and hydrochloric acid. The decolorisation of methyl orange by the reaction products was used to monitor the reaction spectrophotometrically at 525 nm. The method allows the determination of hydrazine in the range 3.0 x 10^-7-3.2 x 10^-5 M. The relative standard deviation for 10 determinations of 6.25 x 10^-6 M hydrazine is 1.2% and the detection limit of the method is 8.5 x 10^-8 M. The method is applied to the determination of hydrazine present in water.
Hydrazine Water Spring Spectrophotometry Kinetic Indirect