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5 International Letters of Chemistry, Physics and Astronomy

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Calculation of electrochemical parameters starting from the polarization curves of ferrocene at glassy carbon electrode

100%

Neghmouche N. S. , Lanez T.

tom Vol. 4

37-45

This work is a contribution to the calculation of electrochemical parameters from the polarization curves of ferrocene. The parameters are: The anodic (Epa) and the cathodic (Epc) peak potentials, as well as the corresponding anodic (ipa) and cathodic (ipc) peak currents, were obtained at different scan rates (0.05, 0.10, 0.30, 0.50 V.s-1). The half-wave potentials (E1/2) of the couple in the investigated solvents have been evaluated. The diffusion coefficients (D) have been calculated using the Randles-Sevcik equation.

Electrochemical properties of N'-ferrocenylmethyl-N'-phenylbenzohydrazide in aqueous and organic mediums

100%

Nacer S. N. , Lanez T.

tom Vol. 5

76-85

We carried out a detailed study of the kinetics of oxidation of N'-ferrocenylmethyl-N'-phenylbenzohydrazide (FcX) to ferrocenium ion (FcX+) in aqueous and organic mediums. This study using cyclic (CV) and rotating disk electrode (RDE) voltammetry showed that the FcX/FcX+ redox couple is reversible. The N'-ferrocenylmethyl-N'-phenylbenzohydrazide and ferrocenium ion diffusion coefficients (D) were calculated from these results. In addition, the electron transfer rate constant and the exchange current density for the oxidation of ferrocene were determined. A comparison of the kinetic data obtained from the two electrochemical techniques appears to show that the data from the RDE experiments are more reliable because they are collected under strict mass transport control.

The Effect of Hydrazide group on the oxydation of ferrocene at two different electrodes using Rotating Disk Electrode (RDE) in organic medium

100%

Nacer S. N. , Lanez T.

tom Vol. 7, iss. 1

1--7

Through this work we adopted Rotating Disk Electrode (RDE) Voltammetry to study the kinetics of oxidation and the effect of hydrazide group on ferrocene in organic medium. Thus, two different electrodes (Pt and Ge) were used in order to determine this latter. According to the ferrocene taken as a witness the hydrazide group related to the ferrocene made oxidation more difficult. This ferrocenic derivative showed an electrochemical stability, a reversible electrochemical system and an electronic attractor effect of these substitutional ferrocene groups. Finally, we calculated some electrochemical parameters which were: the diffusion coefficients (D), the layer thickness in addition to the electron transfer rate.

A Facile Electrochemical Analysis to Determine Antioxidant Activity of Bee Pollen

100%

Rebiai A. , Lanez T.

2013

tom Vol. 9, iss. 1

31-38

The aim of this study was to determine the phenolic and flavonoid content, and antioxidant properties of tow samples of bee pollen harvested from Algeria. The content of total polyphenolic compounds, flavonoids, and antioxidant activity by the cyclic voltammetry method were determined. The contents of polyphenolic compounds was 22.68 mg/g for the pollen from Blida and 21,9 mg/g for Tipaza pollen. High antioxidant activities were found for the cyclic voltammetry method, with values that ranged from 22,3 to 27,63 mg of AAE•g–1 pollen. The bee pollen of Blida showed high antioxidant activity probably due to the high content of polyphenolic compounds present in pollen.

Electrochemical impedance spectroscopy as a mean of measuring film thickness of calcium sulfate precipitate on an XC70 carbon steel

80%

Lanez T. , Chaabia N. , Belaid A.

tom Vol. 13, iss. 1

54-61

In this paper we present the use of electrochemical impedance spectroscopy measurement as a tool to measure the thickness of calcium sulphate film formed on an XC70 carbon steel. The solution used is a mixture of sodium sulphate and calcium chloride solution at different concentrations. The film thickness of calcium sulphate is estimated, after an immersion time of 4 days. The results indicate reciprocal relationship between measured capacitance and thickness of calcium sulphate film.