Electroanalysis of nirofurazone at silver particles and graphite powder composite electrode

Zoubir J.,Assabbane A.,Bakas I. 한국탄소학회 2022 Carbon Letters Vol.32 No.3

The main objective of the research was to deposit thin films of silver on a graphite carbon paste in a phosphate buffer medium using an electrochemical method. To construct a nitrofurazone detection sensor that is highly sensitive. Different manufacturing parameters, such as electrodeposition potential, pH effect, potential scan rate effect, and number of scan cycles, were examined in this section. The parameters were optimized to improve the deposited silver layers various electrocatalytic characteristics. The Nitrofurazone reduction process is diffusion controlled, as seen by the linear variation of Epc with log(v). The constructed Ag-NPs@CPE electrod has excellent electrical characteristics a large active surface area and low background with extremely high electrical conductivity, according to structural and electrochemical characterizations such as Scanning electron microscopy, X-ray diffraction (XRD) and cyclic voltammetry. The constructed sensor has a very remarkable analytical performance for nitrofurazone molecule identification, with a very low detection limit of about 10–8 M. The detection of nitrofurazone using our Ag-NPs@CPE sensors in real samples contaminated with the antibiotic nitrofurazone, such as tap water and urine. In the selected sample, the electroanalytical findings reveal a very satisfactory recovery rate of more than 94 percent.

One-shot synthesis of a nickel oxide/carbon composite electrocatalyst for a sensor capable of electrochemically detecting the antibiotic chloramphenicol in real samples

Zoubir Jallal,Radaa Chaimae,Bakas Idriss,Tamimi Malika,Qourzal Samir,Assabbane Ali 한국탄소학회 2023 Carbon Letters Vol.33 No.3

In this study platform, electrocatalytic detection of the antibiotic chloramphenicol (CAP) in phosphate buffer (pH 7) was easily achieved using a carbon paste electrode modified with NiO nanoparticles (note NiO-CPE). The peak reduction potential of chloramphenicol on the modified electrode is at (− 0.60 V/NiO-CPE vs. Ag/AgCl), its electrochemical behavior is completely irreversible, and controlled by adsorption phenomena. An excellent electrocatalytic activity has been demonstrated by the modified elaborated electrode towards the NO2 attracting group on the side chain of chloramphenicol. The structure and chemical composition of the NiO-CPE sensor were analyzed by SEM, and the X-ray diffraction results indicated that nickel oxide microcrystals were formed on the carbon sheets. The electrochemical characteristics of the NiO-CPE sensor were examined by cyclic voltammetry and electrochemical impedance spectroscopy in comparison with the unmodified carbon. Since the DPV technique allows plotting the linearity curve between the electrocatalytic current intensity of the Chloramphenicol peak and their concentration, the proposed sensor showed a remarkable detection limit of 1.08 × 10–8 mol/L M (S/N = 3) and a wide determination range from 100 to 0.1 µM for Chloramphenicol. The developed sensor was successfully applied in the detection of Chloramphenicol in real samples.

Further Results on Chebyshev and Steffensen Inequalities

Dahmani, Zoubir,Bounoua, Mohamed Doubbi Department of Mathematics 2018 Kyungpook mathematical journal Vol.58 No.1

By making use of the Riemann-Liouville fractional integrals, we establish further results on Chebyshev inequality. Other Steffensen integral results of the weighted Chebyshev functional are also proved. Some classical results of the paper:[ Steffensen's generalization of Chebyshev inequality. J. Math. Inequal., 9(1), (2015).] can be deduced as some special cases.

ON TRANSLATION SURFACES WITH ZERO GAUSSIAN CURVATURE IN LORENTZIAN SOL₃ SPACE

BELARBI, LAKEHAL,ZOUBIR, HANIFI The Korean Society for Computational and Applied M 2022 Journal of applied mathematics & informatics Vol.40 No.5-6

In this work we classified translation invariant surfaces with zero Gaussian curvature in the 3-dimensional Sol Lie group endowed with Lorentzian metric.

Electrochemical degradation of Orange G in K₂SO₄ and KCl medium

Hanene Hamous,Aicha Khenifi,Zohra Bouberka,Zoubir Derriche 대한환경공학회 2020 Environmental Engineering Research Vol.25 No.4

In this work, a detailed study on the electrochemical degradation of an azo dye, Orange G is performed using a platinum electrode. Indeed, the influence of the dye concentration (50-150 mg/L), the pH of the medium and the density of the electric current is studied on the rate of discoloration, the rate of mineralization, the efficiency of the electric current and the energy consumption. The UV-visible spectra of OG plotted against the degradation time show the decrease of the intensity of the characteristic dye peaks. In an environment rich in chlorides, all peaks disappear after 15 min of degradation. However, the peaks at wavelengths of 200 and 290 nm appeared after one hour of treatment. In K₂SO₄, the eliminated percentages are respectively 46, 54 and 61% for wavelengths of 245, 330 and 480 nm. This suggests that the degradation mechanisms in K₂SO₄ and KCl environments are not the same. In the middle rich in chlorides, the eliminated percentage of OG did not seem to be affected by the concentrations increase. These results confirm the hypothesis that electrochemical oxidation process is very favorable for concentrated pollutants discharge.

Validation of a New Design of Tellurium Dioxide-Irradiated Target

Aziz Fllaoui,Younes Ghamad,Brahim Zoubir,Zinel Abidine Ayaz,Aissam El Morabiti,Hafid Amayoud,El Mahjoub Chakir 한국원자력학회 2016 Nuclear Engineering and Technology Vol.48 No.5

Production of iodine-131 by neutron activation of tellurium in tellurium dioxide (TeO2) material requires a target that meets the safety requirements. In a radiopharmaceutical production unit, a new lid for a can was designed, which permits tight sealing of the target by using tungsten inert gas welding. The leakage rate of all prepared targets was assessed using a helium mass spectrometer. The accepted leakage rate is ≤ 10−4 mbr.L/s, according to the approved safety report related to iodine-131 production in the TRIGA Mark II research reactor (TRIGA: Training, Research, Isotopes, General Atomics). To confirm the resistance of the new design to the irradiation conditions in the TRIGA Mark II research reactor's central thimble, a study of heat effect on the sealed targets for 7 hours in an oven was conducted and the leakage rates were evaluated. The results show that the tightness of the targets is ensured up to 600°C with the appearance of deformations on lids beyond 450°C. The study of heat transfer through the target was conducted by adopting a one-dimensional approximation, under consideration of the three transfer modes—convection, conduction, and radiation. The quantities of heat generated by gamma and neutron heating were calculated by a validated computational model for the neutronic simulation of the TRIGA Mark II research reactor using the Monte Carlo N-Particle transport code. Using the heat transfer equations according to the three modes of heat transfer, the thermal study of I-131 production by irradiation of the target in the central thimble showed that the temperatures of materials do not exceed the corresponding melting points. To validate this new design, several targets have been irradiated in the central thimble according to a preplanned irradiation program, going from 4 hours of irradiation at a power level of 0.5 MW up to 35 hours (7 h/d for 5 days a week) at 1.5 MW. The results show that the irradiated targets are tight because no iodine-131 was released in the atmosphere of the reactor building and in the reactor cooling water of the primary circuit.

SOLVABILITY FOR A CLASS OF FDES WITH SOME (e₁, e₂, θ)-NONLOCAL ANTI PERIODIC CONDITIONS AND ANOTHER CLASS OF KDV BURGER EQUATION TYPE

Iqbal Jebril,Yazid GOUARI,Mahdi RAKAH,Zoubir Dahmani 경남대학교 기초과학연구소 2023 Nonlinear Functional Analysis and Applications Vol.28 No.4

In this paper, we work two different problems. First, we investigate a new class of fractional differential equations involving Caputo sequential derivative with some $(e_1,e_2, \theta )-$periodic conditions. The existence and uniqueness of solutions are proven. The stability of solutions is also discussed. The second part includes studying traveling wave solutions of a conformable fractional Korteweg-de Vries-Burger (KdV Burger) equation through the Tanh method. Graphs of some of the waves are plotted and discussed, and a conclusion follows.