Browsing by Author "Lanez, T."

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Chemical Composition And Antioxidant Activity Of Apis Mellifera Bee Pollen From Northwest Algeria
(University of Eloued جامعة الوادي, 2012-07-01) Rebiai, A.; Lanez, T.
The aim of this study was to assess the nutritional compositionand antioxidant activity of bee pollen produced in the North western region of Algeria.The content of total phenolic compounds,flavonoids, and antioxidant activity using the molybdate ion reductionmethod were determined. The meancontents of phenolic compounds and total flavonoids were 30.46 ± 8.22 mgof GAE.g–1 pollen and 8.92 ± 5.5 mg of RE.g–1 pollen, respectively. Highantioxidant activities were found for the molybdate ion reductionmethod, with values that ranged from 71.95 to 101.5μg of GAE.g–1 pollen. The bee pollen ofBoufarikshowed high antioxidant activity probably due to the high contentof phenolic compounds present in pollen.
Comparative Study Of Honey Collected From Different Flora Of Algeria
(University of Eloued جامعة الوادي, 2014-01-01) Rebiai, A.; Lanez, T.
The aim of the present study was to evaluate the physical and chemical properties of five Algerian unifloral types of honey. Several physical parameters of honey, such as pH, moisture content, electrical conductivity, total dissolved solids, color intensity and total sugar content, were measured. The mean pH, moisture content, EC and water insoluble solids of Algerian honey were 4.41± 0.58, 15.3 ± 1.5%, 0.324± 0.116 mS/cm and 0.141± 0.065%, respectively. The mean color was 81 ± 72 mm Pfund. The majority of honey samples test results (moisture content, electric conductivity and acidity) levels were within the acceptable range of world honey standards.
Contribution To The Development Of A Simulation Software Performance And Sharing Ratio In Liquid-liquid Extraction
(University of Eloued جامعة الوادي, 2011-07-01) Hadj Seyd, A.; Lanez, T.
The present work is to develop software to predict the value yield and the distribution coefficient in the process of liquid-liquid extraction of components of a mixture, from mathematical models expressing these entities, based on equations equilibrium between liquid-liquid phases, and predict the conditions under which the extraction operation is favorable, unfavorable or impossible to realize, by studying the variation of the entities cited, based on the parameters influencing the extraction, which are: initial concentrations, rate of solvent and pH, in the case of a simple extraction (extraction of neutral products) or when it is reactive (extraction of complex acids or bases) for one or more components. The programming language used is "Delphi" which is a very powerful oriented object programming under Windows.
Corrosion Inhibition Of Carbon Steel Xc70 In H2so4 Solution By Ferrocenederivative3- (ferrocenylmethylamine) benzonitrile
(University of Eloued جامعة الوادي, 2012-07-01) Zaiz, T.; Lanez, T.
In this work, we studied the efficiency of corrosion inhibition of carbon steel XC70 in H2SO4 0.5 M aqueous solution using ferrocenyl derivativessynthesized in our laboratory, this compound is: 3-(ferrocenylmethylamine)benzonitrile. The inhibitory potential of this compound was determined by electrochemical techniques based on Tafel segments. The results show that the studied compound has an efficiency of inhibition which depends on its concentration.The adsorption of these compounds on the surface of the metal is a chemical adsorption. The inhibition of corrosion reached 84 % at a concentration of 50 ppm.
Determination Of Binding Parameters Of 2-(ferrocenylmethyl-amino)benzonitrile And 3-(ferrocenylmethylamino)benzo-nitrile With 1,1-diphenyl-2-picrylhydrazyl Free Radical
(University of Eloued جامعة الوادي, 2016-01-01) Lanez, T.; Henni, M.
Spectrophotometric techniques based assay were developed for the determination of binding parameters like binding constant and binding free energy of two potential antioxidants ferrocene derivatives: 2-(ferrocenylmethylamino)benzonitrile (2FMAB), 3-(ferrocenylmethyl-amino)benzonitrile (3FMAB), and a standard ascorbic acid (AA) with 1,1-diphenyl-2-picrylhydrazyl radicals (DPPH). Obtained resultants indicated that the adduct 3FMBA-DPPH shows highest binding constant and highest binding free energy (2.28×105 M-1) and (-30.59 KJmol-1) respectively. Binding free energy of 3FMAB-DPPH is almost three times greater than that of the adduct 2FMAB-DPPH (-10.47 KJmol-1) and also is greater than the adduct formed between the standard antioxidant ascorbic acid and 1,1-diphenyl-2-picrylhydrazyl radicals (AA-DPPH) (-19.29 KJmol-1).
Electrochemical Studies Of N'-ferrocenylmethyl-n'-phenylbenzohydrazide At Glassy Carbon Electrode In Different Medium
(University of Eloued جامعة الوادي, 2011-07-01) Khelef, A.; Neghmouche, N. S.; Lanez, T.
The oxidative electrochemistry of N'-Ferrocenylmethyl-N'-Phenylbenzohydrazide FcX was studied in acetonitrile with tetrabutylammonium hexafluorophosphate as the supporting electrolyte and aqueous ethanol using the electrochemical technique. This study using cyclic (CV) and rotating disk electrode (RDE) voltammetry showed that the FcX/FcX+ redox couple is reversible in this electrolytes. The effects of changing the scan rate on the electrochemical behavior of ferrocene have been examined. A comparison of the electrochemical behavior of ferrocene and N'-Ferrocenylmethyl-N'-Phenylbenzohydrazid have been examined.
ELECTROCHEMISTRY CHARACTERIZATION OF FERROCENE/FERRICENIUM REDOX COUPLE AT GLASSYCARBON ELECTRODE
(University of Eloued جامعة الوادي, 2009-07-01) Neghmouche, N. S.; Khelef, A.; Lanez, T.
In the present work the oxidation of ferrocene, , to the ferrocenium cation, , was examined in the solvents dichloromethane, and aqueous ethanol using the technique of cyclic voltammetry. 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).Â The diffusion coefficients (D) have been calculated using the Randles-Sevcik equation. The effects of changing the scan rate on the electrochemical behavior of ferrocene have been examined.
Estimating Octanol/water Partition Coefficient For Selected Ferrocene Derivatives Using Xlogpv2.0 Approach
(University of Eloued جامعة الوادي, 2016-09-01) Ahmedi, R.; Lanez, T.
Octanol/water partition coefficients P of several substituted ferrocene were calculated on the basis of the adaptation of the existing XlogPv2.0 approach. The predicted of calculated partition coefficients values of logP for selected ferrocene derivatives was compared with known experimental values taken from literature.The shown Results confirmed that the calculated partition coefficients were in good accord with experimental values. The average of absolute error is 0.12, and the obtained correlation coefficient value R^2for the linear dependencies between experimental and calculated partitions coefficients is 0.977.
EVALUATE OF THE ANTIOXIDANT ACTIVITY OF POTATOES BY RADICAL SCAVENGING ACTIVITY USING O•2− AND DPPH
(University of Eloued جامعة الوادي, 2018-01-01) Benhaoua, K.; Lanez, T.
This work aimed to evaluate antioxidant capacity of four kinds of Solanum tuberosum L (potato), the total phenolic content of ethanolic extracts of whole roots shows values ranged from 19.21 to 08.88 mg AG/g of extract, the amount of total flavonoids content varied from 25.03 to 10.91mg rutin/g of extract. However, this phytochemical content of sample extracts had an effect on the capacity antioxidant which measured with scavenging radical activity, was carried out spectroscopy assay by using DPPH radical and cyclic voltammetry assay for superoxide anion radical (O•2−). The IC50 values ranged from 1.21 to 3.86 mg/ml and from 1.03 to 1.81 mg/ml for the inhibition of DPPH and superoxide anion radical respectively. Also, the diminution of the current peak of (O•2−) in absence and presence of sample extract was successfully investigated for the determination of interactions parameters as binding constant Kb, the ratio of binding constants, binding free energy and mode of interaction. For these results, there was a significant statistically (p<0.005). All the Solanum tuberosum L showed appreciable levels of antioxidant activities and can be promoted as a natural antioxidant preference in food.
Evaluation Of Antioxidant Activity And Polyphenolic Contents Of Two South Algerian Eggplants Cultivars
(University of Eloued جامعة الوادي, 2016-05-01) Djouadi, A.; Lanez, T.; Boubekri, C.
Polyphenolic compounds and antioxidant activity in eggplants (Solanum melongena L.) seem to depend on cultivar, maturity stage, environmental conditions and the part of the fruit. In this work, the polyphenolic content and antioxidant activity of pulp, whole fruit and peel from fresh dark-purple and white eggplant varieties cultivated in Southern Algeria were measured. Total phenolic content were determined by Folin-Ciocalteu test, and antioxidant activity measured using cyclic voltammetry. Correlations between antioxidant activity and total phenolic content were also examined. Within each cultivar, the total phenolic content and antioxidant activity were highest in the peels, followed by the whole fruit and the pulp. In the peel, whole fruit and pulp the dark-purple eggplant had the highest total phenolic contents and the highest total antioxidant activities.
Evaluation Of The Inhibitory Effectiveness Of Three Ferrocene Derivatives For Corrosion Of Steel Xc70 By Spectroscopy Of Electrochemical Impedance
(University of Eloued جامعة الوادي, 2011-07-01) Rahim, O.; Ben Chenna, A.; Zaiz, T.; Chaouch, K.; Lanez, T.
In this work, we studied the efficacy of corrosion inhibition of carbon steel X70 in HCl 1M solution using ferrocenyl compounds prepared in VPRS laboratory, these compounds are: N-(férrocenyl méthyl)-2-nitro aniline(Fc12), N-(férrocenyl méthyl)-3-nitro aniline(Fc13) and N-(férrocenyl méthyl)-4-nitro aniline(Fc14). The inhibitory potency of these compounds was determined by the electrochemical impedance spectroscopy (EIS). The overall results show that these compounds have varying percentages of inhibition. The adsorption of these compounds on the surface of the metal is a chemical adsorption. In HCl 1M, the compound Fc12 had the best ability of inhibition at a concentration of 70ppm (R = 91.24%).
Prediction Of Octanol/water Partition Coefficient Of Selected Ferrocene Derivatives Using Rekker Method
(University of Eloued جامعة الوادي, 2011-07-01) Ahmedi, R.; Lanez, T.
In this work we present a theoretical approach for the determination of octanol/water partition coefficient of selected ferrocenes bearing different substituents, the calculation is based on the adaptation of the Rekker method. Our prediction of obtained theoretical partition coefficients values of logP for all studied substituted ferrocene was confirmed by comparison with known experimental values obtained mainly from literature. The results obtained show that calculated partition coefficients are in good agreement with experimental values. For estimation of the octanol/water partition coefficients of the selected compounds, the average absolute error of log P is 0.13, and The correlation coefficient is R2 = 0.966.
Square Wave Voltammetric Determination Of Lead In Commercial Kohl Using A Glassy Carbon Electrode
(University of Eloued جامعة الوادي, 2011-07-01) Saha, M. A.; Alia, M.; Rebiai, A.; Lanez, T.
A simple sensitive square wave voltammetric method for the determination of lead contamination of several kohl samples purchased from Algeria retail stores was developed using glassy carbon electrode. The peak current response of 5 standards aqueous solution of lead in NaNO3 as supporting electrolyte was observed showing a linear calibration curve in the concentration range of 4×10-3 – 2.5×10-4 mol/l of lead. Over this concentration range, the equation obtained from the linear calibration graph for lead is Y = 0.00068 + 0.0093x with a correlation coefficient of r2 = 0.987. Following this step, the potential of an aqueous solution of 12 kohl samples containing 2 M nitric acid solution as supporting electrolyte is then swept in the same range of potential (-400 to -700 mV). The amount of lead is then deduced using the linear calibration graph for lead. The results showed up to 52.14% of lead present in kohl, this concentration was over the safe limits of lead set by the world health organization standards. However; only five commercial samples of ko
Study Of Antioxidant Capacity Of Different Parts Of Two South Algerian Eggplant Cultivars
(University of Eloued جامعة الوادي, 2012-07-01) Boubekri, C.; Rebiai, A.; Lanez, T.
In this study the antioxidant capacity of ethanolic EE and water WE extracts fromdifferent parts (calyx, peel, and pulp) of eggplant (Solanum melongena L) were evaluated using cyclic voltammetry.The antioxidant capacity of different parts of eggplant was measured using ascorbic acid equivalent antioxidant capacity assays. The peel extracts of both dark purple and white samples showed the highest antioxidant capacity (66.78and 75.62 mg/g) followed by pulp (16.54 and 30.56 mg/g), and calyx (14.82 and 21.27 mg/g). These results indicate that antioxidant capacity of eggplant varied by parts and solvents.
Synthesis, Crystal Structures, Hydrogen Bonding Graph-sets And Theoretical Studies Of Nickel (+ii) Co-ordinations With Pyridine-2,6-dicarboxamide Oxime
(University of Eloued جامعة الوادي, 2017-01-01) Hamdaoui, A.; Messai, A.; Benyza, N.; Lanez, T.; Sayin, K.
The pyridine-2,6-dicarboxamide oxime, C7H9N5O2, was Synthesis and characterises with 1H NMR and FTIR spectroscopy . The reaction of this ligand with nickel (II) perchlorate yielded green crystals of formula [Ni(C7H9N5O2)2]2+,2[ClO4]-, which crystallized in the monoclinic space group C2/c with a = 14.915(2), b = 0.895(2), c = 8.205(1) Å, β = 114.69(1), and Z = 4. The complex consists of discrete cations (+II) and one perchlorate anion, the cations existing in a slightly distorted octahedral complex with bonding through the heterocyclic and oxime nitrogen atoms. The structure is held together through N-H…O, O-H…O and C-H...O hydrogen bonds occurring between the coordinated oxime molecules and the perchlorate counter-ion. Computational investigations of nickel(II) complex are done by using M062X method with 6-31+G(d)(LANL2DZ) basis set in vacuo.
Synthesis, Quantum Chemical Computations And X-ray Crystallographic Studies Of A New Complex Based Of Manganese (+ii)
(University of Eloued جامعة الوادي, 2017-05-01) Benyza, N.; Messai, A.; Hamdaoui, A.; Lanez, T.; Sayin, K.
The ligand oxime, C7H9N5O2, was Synthesis and characterises with different characterization methods such as 1H NMR and FTIR spectroscopy. The complexation of this ligand with manganese (II) perchlorate yielded pink crystals of formula [Mn (C7H9N5O2)2]2+, 2[ClO4]-, which crystallized in the monoclinic space group P21/n with a = 12.824(3), b=13.799(2), c=15.441(4)Å, β = 100.17(2), and Z = 4. The complex consists of cations (+II) and two perchlorate anions, the cations part existing in a slightly distorted octahedral complex. Computational investigations of manganese (II) complex are done by using the DFTmethod with B3LYP functional in conjunction with the 6-31G(d,p) and lanl2dz basis sets in the gas phase imposing the C1 and C2v symmetries.