The voltammetric characteristics of bismuth (III)-oxinate in chloroform at the mercury electrode were investigated and a quasi-reversible behavior for Bi(III) oxinate reduction was confirmed Preceded by the extraction of Bi(III) oxinate in chloroform, differential pulse POLAROGRAPHY, was developed in the extracts for determination of the trace-bismuth. The linear range of the calibration graph and the detection limit respectively were: 1x10-6 -5 x 10-5 M and 4.7x10-7 M of Bi(III). Suitability and accuracy of the proposed method for determination of trace-bismuth was established by the analysis of a metallic aluminum sample.

The voltammetric characteristics of Mo (VI) oxinate at the mercury electrode, in the presence of tri-butylammonium perchlorate (tri-BAP) and piperidinium perchlorate (PP) + piperidine (P) as two different types supporting electrolytes, have been studied in chloroform. With the both supporting electrolytes a two electron irreversible process for the reduction of Mo (VI) oxinate was observed. Preceded by a solvent extraction of Mo (VI) oxinate in chloroform, the DP method was used for the determination of molybdenum. In the presence of 0.2 M tri-BAP as supporting electrolyte, the calibration graph was linear over the range 0.5 to 50 (M. and the detection limit was 0.16 (M about 10 times lower than the case of PP + P. The proposed method using Mo (VI) oxinate-tri-BAP system has been successfully applied for the determination of molybdenum in steel.

Electrosynthesis of epoxystyrene was carried out in “CH3CN + H2O + Styrene” medium at the presence of bromide ions as catalyst, on Pt electrode. Purification and identification of product was performed by gas chromatography (GC) and spectroscopic methods. Also, DC, AC and DP polarographic behavior of epoxystyrene was studied. The influence of different factors on the yield of indirect preparation of epoxystyrene was also investigated.

The complexation reactions between T1(I) and Pb(II)ions and 1,2-dihydroxyethane, 1,2-diaminoethane, diethanolamine, triethanolamine, hexamethyleneteramine, and 1,2,3- trihydroxypropane were studied in 90% ethanol solution at 25°C using an AC polarographic technique. The stoichiometry and the stability of the complexes were determined by Lingane method. The stability of the resulting complexes was found to vary in the following order: 1,2,3-trihydroxypropane, 1,2-dihydroxyethane, hexamethylenetetramine, 1,2-diaminoethane, triethanolamine and diethanol amine. The last complex was the most stable one. The influence of binding sites, nature of solvent and metal ions and entropy and enthalpy effects on stability of complexes are discussed.

Background: Lead and cadmium can enter the human body through consuming the liver of animals such as sheep, which may accumulate and cause adverse effects. The levels of lead and cadmium in the liver samples of slaughtered sheep in Zanjan and Sanandaj were investigated in the summer of 2014. Methods: 96 Samples were collected from both cities. Lead and cadmium levels were measured by anodic stripping voltammetry (ASV) after digestion with nitric acid and hydrogen peroxide in 3 steps by a 400-watt microwave digester. Lead and cadmium concentrations were determined in μ g/L using standard solutions of lead and cadmium as standard addition in their specific potential,-0. 42 and-0. 58 V for lead and cadmium, respectively. Results: Mean values of cadmium in the livers of sheep in Zanjan and Sanandaj were 0. 42 ± 0. 13 and 0. 35 ± 0. 13 mg/kg, respectively, which had no significant difference (P < 0. 05). On the other hand, mean concentrations of lead in the livers of sheep in Zanjan and Sanandaj sheep were equal to 3. 69 ± 1. 43 and 2. 36 ± 0. 18 mg/kg, respectively, which had a significant difference (P < 0. 05). Conclusion: The concentrations of lead and cadmium in the livers of sheep were higher than WHO standards. However, only the lead levels were higher than the maximum residue levels (MRLs) standard lists. The obtained results can be due to the activities of lead industries and factories in both cities, which may increase pollution levels in the water, air, and animal feed.

A highly selective rapid and economical differential pulse polarographic method has been developed for the determination of trace amounts of cadmium and lead present together in various standard allays and biological samples after adsorption of their 1-(2-pyridylazo)-2-naphthol complexes on microcrystalline naphthalene. Cadmium and lend complexes are equantitatively adsorbed on microcrystalline naphthalene in the pH range of 8.2-11.0 for cadmium and 8.4-11.5 for lead After filtration, the solid mass is shaken in 10 mt of 1 M hydrochloric acid and these metals are determined simultaneously by differential pulse POLAROGRAPHY (DPP). Detection limits are: 0.07 mu g/mL for Cd and 0.1 mu g/mL for Pb (signal to noise ratio=2). While linearity is maintained in the concentration range 0.1-150 mu g/mL for Cd and 0.1-300 mu g/mL for Pb with a correlation coefficient of 0.9996 and relative standard deviations of 0.98 and 1.1% respectively Various parameters such as the effect of pH, volume of aqueous phase and interference of a number of metal ions on the determination of cadmium and lead have been studied in detail to optimize the conditions for their simultaneous (based upon the difference in their E-p values) determination in complex materials.

This study was carried out to investigate heavy metals concentration in the sediments ofLifeh and Busaf coastal waters. Four stations in the Khore-Mussa western coasts were sampled seasonally from winter 2006 to autumn 2007. Concentration of Hg was measured using Voltammeter and other metals were analyzed using POLAROGRAPHY method.The mean concentrations were 68.8 for Zn, 23.5 for Pb, 21.8 for Cu, 12.8 for Co, 2.14 for Cd, 73.6 for Ni and 0.19 for Hg in mg/kg. According to the concentration results we ranked theheavy metals as: Ni > Zn > Pb > Cu > Co > Cd > Hg. Based on Muller geochemical index (Igeo), sediment quality for Pb and Hg is in class II (moderately polluted) and for other metals is in class 0 (unpolluted). The similarity between stations and different parameters were demonstrated using PCA and Clustering analyses.Although significant differences were not observed between the studied stations, but PCA analysis of heavy metals concentrations showed some similarity and differences between them. These similarities might be linked to geochemical characters of sediments and the nature of water currents in the study area.

The electrochemical behaviour of nifedipine (I), nitrendipine(II) and their photodegradation products has been studied by employing electrochemical techniques tit chloroform and in 1:4 mixture of chloroform-isopropanol using piperidinium perchlorate (PPC) as supporting electrolyte. It has been shown that I and II undergo in a 4e, 4H(+) irreversible reduction reaction, while the reduction product, phenylhydroxylamine, is oxidized in a 2e, 2H(+) reversible process to an unstable nitrosophenyl compound. Photodegradation of I and II by sunlight produces a nitrosophenyl derivative which is reversibly reduced to the corresponding unstable phenyl-hydroxylamine. No significant change is observed in electrochemical properties of drugs by passing from chloroform to chloroform-isopropanol mixture. The possibility of analysis of I and II by dp POLAROGRAPHY is also verified.