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A novel and ultrasensitive non‑enzymatic electrochemical glucose sensor in real human blood samples based on facile one‑step electrochemical synthesis of nickel hydroxides nanoparticles onto a three‑dimensional Inconel 625 foam
(Journal of Applied Electrochemistry, 2023) Rafiaa Kihal; Hassina Fisli; Mohamed Lyamine Chelaghmia; Widad Drissi; Chahira Boukharouba; Sara Abdi; Mouna Nacef; Abed Mohamed Afoune; Maxime Pontié
In this contribution, a simple and novel non-enzymatic electrochemical sensor for the detection of glucose was successfully prepared by direct in situ growth of nickel hydroxide nanoparticles (Ni(OH)2NPs) onto a three-dimensional Inconel 625foam (IN625F) substrate through a facile electrochemical route, using cyclic voltammetry (CV) method in alkaline medium without addition of nickel salts. Then, surface characterization of modifed Ni(OH)2/IN625F electrodes was carried out through advanced technologies, such as scanning electron microscopy (SEM) and X-ray difraction (XRD). The electrochemical catalytic behavior of the fabricated electrodes was investigated using CV and amperometric methods. The results revealed that the novel modifed sensor, Ni(OH)2/IN625F, showed the highest sensitivity of 5685 μAmM−1 cm−2 over a wide linear concentration range from 1 to10 mM, with lowest detection limit (LOD) of 2 μM (S/N = 3), and short response time within<2 s. Therefore, the proposed non-enzymatic electrochemical sensor demonstrated high selectivity and stability, good reproducibility, and low cost. In addition, analysis of human blood samples was performed. Hence, the constructed glucose sensor, Ni(OH)2/IN625F, with suitable performance could be used as a promising material in real human blood samples.
An Associated and Nonassociated Flow Rule Comparison for AISI 439-430TI Forming: Modeling and Experimental Analysis
(2021-09-21) Chahaoui
The plastic anisotropy behavior of ferritic stainless steel (FSS) sheets was analyzed and modeled under associated and nonassociated flow rule approaches. Three orthotropic flow functions, known as quadratic Hill48 and nonquadratic (Yld2000-2d and BBC2005), were developed and employed under an associated and nonassociated flow rule hypothesis. For the NAFR based on the initial anisotropy, the mechanical behavior was described by the nonexponential model functions of Yld2000-2d and BBC2005 to predict the directional dependence of mechanical parameters. It provided a considerable advantage in terms of flexibility and good agreement with the experiment. According to the results, the polynomial fit functions of the transverse versus longitudinal true plastic strain curve were used to describe the designated properties corresponding to a selected level of strain. To describe the evolution of anisotropic hardening and potential plastic hardening, seven different loading conditions were considered. The proposed evolutionary non-AFR Yld2000-2d and BBC2005 criteria showed good accuracy in predicting the evolution of hardening yield and Lankford coefficients depending on the plastic deformation.
An Evolutionary Anisotropic Behavior for DC04 Sheet Using Hill48 Function under Non-Associated Flow Rule Hypothesis
(2022-10-28) Chahaoui
analyzed based on a quadratic Hill48 function and under the application of two plasticity approaches: associated and non-associated flow rule approaches (AFR and NAFR, respectively). The mechanical properties have been modeled, such as the uniaxial flow stresses () and the coefficient of anisotropy r() (or the Lankford parameter). In the identification of anisotropic parameters, the decoupling of the two tensors (strain and stress) under the assumption of non-associated plasticity gives better predictions compared with the experimental. With the purpose of introducing the evolutionary anisotropic path of plastically equivalent characteristics for the uniaxial flow stresses (), the isotropic hardening of mechanical strain hardening function is presented using the following empirical law based on Voce model. Therefore,
Application of Associated and Non-Associated Flow Metal Plasticity for F.S.S Sheet
(2021-01-11) Chahaoui
In the last decade, several phenomenological yield criteria for anisotropic material has been proposed to improve the modeling predictions about sheet metal-forming processes. In regard to this engineering application, two proprieties of models have been used. If the yield function and the plastic potential are not same (not equal), the normality rule is non associative flow rule (NAFR), otherwise, when the stresses yield has been completely coupled to the anisotropic strain rate ratio (plastic potential), is called the associated flow rule (AFR). The non-associated flow rule is largely adopted to predict a plastic behavior for metal forming, accurately about à strong mechanical anisotropy presents in sheet metal forming processes. However, various studies described the limits of the AFR concept in dealing with highly anisotropic materials. In this study, the quadratic Hill1948 yield criteria is considered to predict mechanical behavior under AFR and NAFR approach. Experiment and modeling predictions behaviour of normalized anisotropic coefficient r (θ) and σ (θ) evolved with θ in sheet plane. and the equibiaxial yield stress σb was assumed σb=1 but the rb-values was computed from Yld96 [15]
Constitutive Modelling of an Industrial Rolled Sheet for a DIN 1623 St14 (DC04) Steel
(2019-09-17) Chahaoui
The comprehension of the anisotropy impacts on mechanical properties of the rolled steel sheets was investigated using a non-quadratic anisotropic yield function. In this study, experimental and modelling determination of behavior of an industrial rolled sheets for a DIN 1623 St14 steel were carried out. The yield stresses and Lankford r-values in uniaxial were experimentally determined but the balanced biaxial tension stress states and rb were assumed. The parameters of the associated yield equation, derived from the three orthotropic yield functions proposed by Hill48 and Yld2000-2d, were determined. Predictions and the evolution of normalized yield stress and normalized Lankford parameters (plastic strain ratio) obtained by the presented investigative are considered. In order to describe the path of equivalent plastic behavior, the isotropic hardening function is described using the following various empirical standard formulae based on: Hollomon, Ludwick, Swift and Voce model.
Coupled effect of variable Winkler–Pasternak foundations on bending behavior of FG plates exposed to several types of loading
(Steel and Composite Structures Volume 44, Number 3, August10 2022 , pages 353-369 DOI: https://doi.org/10.12989/scs.2022.44.3.353, 2022-07-15) HIMEUR NABIL; Nabil Himeur, Belgacem Mamen, Soumia Benguediab, Abdelhakim Bouhadra, Abderrahmane Menasria, Benattou Bouchouicha, Fouad Bourada, Mohamed Benguediab and Abdelouahed Tounsi
Abstract This study attempts to shed light on the coupled impact of types of loading, thickness stretching, and types of variation of Winkler–Pasternak foundations on the flexural behavior of simply- supported FG plates according to the new quasi– 3D high order shear deformation theory, including integral terms. A new function sheep is used in the present work. In particular, both Winkler and Pasternak layers are non-uniform and vary along the plate length direction. In addition, the interaction between the loading type and the variation of Winkler–Pasternak foundation parameters is considered and involved in the governing equilibrium equations. Using the virtual displacement principle and Navier's solution technique, the numerical results of non dimensional stresses and displacements are computed. Finally, the non-dimensional formulas' results are validated with the existing literature, and excellent agreement is detected between the results. More importantly, several complementary parametric studies with the effect of various geometric and material factors are examined. The present analytical model is suitable for investigating the bending of simply-supported FGM plates for special technical engineering applications.
Effect of Broken Glass Particle on Stress Transfer of Nylon Matrix Composite
(2023-10-30) Khelifa MANSOURI
Some of the material demands in the advanced industries cannot be fulfilled by monolithic materials. Therefore, composite materials have been developed. The combination of desired properties of thermoplastics and glass particles (high strength and high modulus) is the aim of composites production Particles are becoming increasingly popular reinforcing elements in products made by injection molding. Particles reinforcement allows the polymer to be processed employing the same methods as those used for unreinforced polymers. The loads are not directly applied to the reinforcements, but they are applied to the matrix and some of the loads applied are transferred to the particles. The development of micromechanics equations for the particulate composites follows along the same lines as those for the short fiber reinforced composites. Particles are used to increase the strength or other properties of inexpensive materials during reinforcement with other matrix materials. The objective of this study is to analyse the particle breaking effect in composite made of nylon 66 (PA) matrix reinforced with glass particles, in which the particles diameters of 19.61, 26.15, 39.22 and 78.45 m were used. A volume fraction of 20 % was assumed in each model.
Effect of Reinforcing Particle Shape on the Behavior of Composites Materials
(JOURNAL OF NANO- AND ELECTRONIC PHYSICS, 2021-12-20) Khelifa MANSOURI
In this paper, the effect of particle shape on the mechanic behavior of glass particle reinforced composites is evaluated. Small particles adhere strongly to the polymer, which leads to a strong reinforcing effect. When the total contact surface increases, more loads are transferred to the reinforcing particles. In our previous studies, it has been shown that addition of circular particles with decreasing diameter does not affect the composite. The objective of this research is to investigate the mechanical behavior of thermoplastic matrix composite nylon 66, reinforced with glass particles, under unidirectional tensile loading using finite element analysis. Numerical results are presented for a variety of particle shapes, including circular, triangular, square, rhombic, pentagonal and hexagonal. The results show that Von Mises stresses consistently increased as the shape of the reinforcing particles changed from triangular to square, rhombic, pentagonal, hexagonal and circular in this order.
Experimental Study and Modelling of the Ferritic Steel Anisotropic Behavior under Associated and Non-Associated Flow Rule
(2021-01-05) Chahaoui
In the present study, two different yield criteria were investigated to model and compare the yield thresholds functions for the plastic behavior of rolled sheets. These two different yield criteria as described via Hill48 yield quadratic and F. Barlat Yld2000-2d non-quadratic criterion. For this purpose, an experimental device of simple tensile test and the studied material are described. The experimental results in terms of Yield stress and Anisotropic coefficient are estimated from the Associated Flow Rule (AFR) and Non-Associated Flow Rule (NAFR). However, it is found that the criterion of Yld2000-2d is the most appropriate model in comparison with the experimental results.
Influence of the carburization time on the structural and mechanical properties of XC20 steel
(2021-08-21) Chahaoui
This study focuses on the effect of carburization time on the structural and mechanical properties of low carbon XC20 mild steel (C. Wt.%<0.25). The XC20 steel was carburized with activated carbon with a carbon potential Cp1=1.1%, at 910 °Cat different carburization times of 2, 4 and 6 h. The results obtained show that XC20 steel (non-carburized) has a ferrite-pearlitic structure with a hardness and a Young’s modulus of the order of (150 HV, 26KN/mm2). After carburization, the structure of the carburized layer is transformed in martensite (Fe γ) in which cementite (Fe3C) is imbricated. The depth of the carburized layer and the amount of carbon on the surface gradually increase with increasing carburization time. In addition, the carburized XC20 steel becomes hard and brittle where the hardness and Young’s modulus have been increased for a high holding time until reaching maximum values (845 HV, 48KNmm−2) after 6 h of carburization . However, the toughness of XC20 steel has been reduced from 163 to 40 J cm−2.
Iron (III)-Selective Sensor Based on Modified Glassy Carbon Electrode
(2018) MECHERI NACIRA
The aim of this work is intended to make a comparison between the effects of the presence of potassium ferricyanide (K3[Fe(CN)6]) / potassium ferrocyanide K4[Fe(CN)6]) and the absence of any redox couple for iron (III) determination in aqueous solution using modified Glassy Carbon Electrode. Benzo-18-crown-6 is employed as ionophores for preparing PVC-based membrane sensors selective to iron (III), plasticized with Di-n-octyl phthalate, Tetrabutylammonium tetraphenylborate was used as additive. The measurements performed and characterized by square wave voltammetry methods. Agents were optimized for iron (III) stripping analysis and optimal condition was frequency of 20 Hz, step potential of 6 mV, amplitude of 40 mV, the modified glassy carbon electrode immersed in standard solutions of Fe(III) at PH 2.0 .The measurements are performed in 0.1M NaNO3 and 0.1 M HCl (pH 7). The square wave voltammograms showed a sharp peak around positive potentials + 0.260 V that was used for construction of the calibration curve in a work range from 10-10 until 10-6 mol L-1 of iron, exhibiting a linear correlation coefficient of 0.99, a detection limit of 10-10 mol L-1 and sensibility of 9. /mol L-1, especially, those obtained by the presence of redox couple better than the absence of external redox.
Mechanical Behavior of Particle Reinforced Thermoplastic Matrix Composites Using Finite Element Modeling
(JOURNAL OF NANO- AND ELECTRONIC PHYSICS, 2020-10-25) Khelifa MANSOURI
Particles are becoming increasingly popular reinforcing elements in products made by injection molding. Particles reinforcement allows the thermoplastic to be processed employing the same methods as those used for unreinforced thermoplastic. Ultrafine particles, whose diameters are comparable to the crystalline regions in the polymer, have a prominent reinforcing effect on the elastic properties of the polymer. Small particles adhere strongly to the polymer, which leads to a strong reinforcing effect. In particle reinforced thermoplastic matrix composites, loads are not directly applied to the particles but are applied to the matrix, and some of the applied loads are transferred to the particles. The process of transfer of load between particles and matrix depends on the strength of the interface. In this work, multiparticle composite model was analyzed under tensile load. The purpose of this work is to analyze the influence of particle diameter (the diameters of 19.61, 26.15, 39.22 and 78.45 m were used) on the Von Mises stress of glass particle reinforced thermoplastic nylon 66 matrix composite using finite element analysis (FEA). The second objective is to analyze the effect of particle packing (square, hexagonal and random arrangement) on nanocomposite behavior.
Modelling Mechanical Properties of AISI 439-430Ti Ferritic Stainless Steel Sheet
(2019-05-14) Chahaoui
The comprehension of the anisotropy impacts on mechanical properties of the rolled steel sheets was investigated using a nonquadratic anisotropic yield function. In this study, experimental and modelling determination regarding the behaviour of an industrial rolled sheet for a ferritic stainless low-carbon steel were carried out. The parameters of the associated yield equation, derived from the three orthotropic yield functions proposed by Hill48, Yld96 and Yld2000-2d, were determined. Predictions and the evolution of normalized yield stress and normalized Lankford parameters (plastic strain ratio) obtained by the presented investigative are considered. The forecasts given by the YLD2000-2d criterion are consistent with that of the experience. In order to describe the path of strain behavior, the isotropic hardening function is described using the following four empirical standard formulae based on: Hollomon, Ludwick, Swift and Voce law. More accurately, the anisotropy coefficients of three yield functions are represented as a function of the longitudinal equivalent plastic strain.
New modified selective platinum electrode based on poly (ethylene glycol) for Iron (III) detection in real water
(MECHERI NACIRA, 2017-11-04) Nacira Mecheri, Messaoud Benounis, Houcine Barhoumi,
Purpose – This work aims to determine iron (III) in real water by using a new amperometric sensor on the basis of polyethylene glycol (PEG) to test and characterize a new modified selective platinum electrode. Design/methodology/approach – In this review, the authors focus on testing and characterizing several polymeric membranes by using cyclic voltammetry and square-wave voltammetry (SWV) methods to differentiate the nature of plasticizers (2-Nitrophenyl octyl ether [NPOE], Di-n-octyl phthalate, Bis (2-ethylhexyl) sebacate, PEG. The authors have evaluated the possibility of using crown ether and three zeolite ionophore (faujasite [FAU], Chabazite and ZSM-5) matrixes as novel materials for the selective determination of iron (III) using SWV for the best membranes. Findings – The results demonstrated that the modified platinum electrode presents linear dependence of amperometric signal with a wide linear range of 10 9 to 10 4 mol.L 1 for iron determination, revealing a detection limit of 10 10 mol.L 1 and amperometric sensibility of 58.58 mA/mol. L 1 . The slope of the membrane plasticized with PEG calibration curve is six times higher than that of the other membranes. It was noticed that when the crown ether and the three zeolite ionophores were used, as a new detective material for iron with the membrane plasticized with PEG, the expected results were highly proven. The modified platinum electrode showed high selectivity to iron (III) when the heavy metal ions such as Ni (II), Al (III), Zn (III), Cd (II), Gd (II) and Cu (II) were present. Originality/value – The utility of the method and the efficiency of the best membrane sensor have been accurately tested by the determination of iron in real water samples of Hassi Messaoud, south of Algeria.
The influence of fiber arrangement on the mechanical properties of short fiber reinforced thermoplastic matrix composite
(Revue des Composites et des Matériaux Avancés, 2017) Khelifa MANSOURI
Short fibers are becoming increasingly popular reinforcing elements in products made by extrusion or injection molding. Short-fiber reinforcement allows the polymer to be processed employing the same methods as those used for unreinforced polymers. In short fiber composites, loads are not directly applied on the fibers but are applied to the matrix and transferred to the fibers through the fiber ends. Thermoplastics reinforced with short fibers are increasingly used in many industrial applications due to their attractive mechanical properties, rapid processing and relatively low manufacturing cost. However, the concentration and the orientation of the fibers vary from one point to the other. In this work, multi fiber composite model was analyzed under tensile load. The purpose of this work is to analyze the influence of fiber arrangement on the Von Mises stress of glass fiber reinforced thermoplastic nylon66 matrix composite using finite element analysis (FEA).
Three-dimensional transient CFD modeling of multiple finned aluminum foam heat sinks in a horizontal channel
(2023-07-28) Boulahrouz Salim, Saoudi Abdenour, Chahaoui Oualid , Hadi M. Marwani, Rokkaya Sami, N.I. Aljuraide, Raed H. Althomali, Mohammed M. Rahman , Meser M. Ali i, M.A. El Bouz j
Finned metal foam heat sinks are well-known because of their excellent performance in cooling of powered electronics. In this study, three-dimensional transient numerical simulations of finned aluminum foam heat sinks in a forced convection of air were carried out using commercial COMSOL. The geometry under consideration consists of an array of finned aluminum foam heat sinks mounted on heater blocks and placed on a plate in a horizontal channel. Heat sink aluminum foam regions were considered as porous media with a local nonequilibrium thermal model to evaluate thermal characteristics, while the Forchheimer-Brinkman extended Darcy model is considered for the flow analysis. Our main concern in the present study is to evaluate the transient thermal–hydraulic behavior and the cooling performance under constant flux heat sources while varying the Reynolds number and variable morphological parameters of the aluminum foam, i.e., porosity (ε) varied from 0.85 to 0.95. The thermal performance ratio and the average Nusselt number of the finned aluminum foam heat sinks are 23.14% and 30%, respectively, larger than the finned aluminum heat sinks. As the Reynolds number increases, the thermal characteristics are enhanced, and the pressure drop is increased. An increase in porosity causes a reduction in heat transfer rate and an elevation of pressure drop.
Three-dimensional transient CFD modeling of multiple finned aluminum foam heat sinks in a horizontal channel
(2023-07-28) Chahaoui
Finned metal foam heat sinks are well-known because of their excellent performance in cooling of powered electronics. In this study, three-dimensional transient numerical simulations of finned aluminum foam heat sinks in a forced convection of air were carried out using commercial COMSOL. The geometry under consideration consists of an array of finned aluminum foam heat sinks mounted on heater blocks and placed on a plate in a horizontal channel. Heat sink aluminum foam regions were considered as porous media with a local nonequilibrium thermal model to evaluate thermal characteristics, while the Forchheimer-Brinkman extended Darcy model is considered for the flow analysis. Our main concern in the present study is to evaluate the transient thermal–hydraulic behavior and the cooling performance under constant flux heat sources while varying the Reynolds number and variable morphological parameters of the aluminum foam, i.e., porosity (ε) varied from 0.85 to 0.95. The thermal performance ratio and the average Nusselt number of the finned aluminum foam heat sinks are 23.14% and 30%, respectively, larger than the finned aluminum heat sinks. As the Reynolds number increases, the thermal characteristics are enhanced, and the pressure drop is increased. An increase in porosity causes a reduction in heat transfer rate and an elevation of pressure drop.
Vickers Hardness Test of Steel Pipes Welded by High Frequency Induction
(JOURNAL OF NANO- AND ELECTRONIC PHYSICS, 2022-02-28) Khelifa MANSOURI
The rapid development of design technology and strong market competition have prompted us to look into the field of production of steel pipes with a process that perfectly meets industrial requirements, which is high frequency (HF) induction welding, which is the most common welding process to produce steel pipes. This process is currently better known for the manufacture of pipes of different diameters at the Tube Gaz unit in Tebessa (Algeria). Among the various known destructive tests, the Vickers hardness test is used to control the pipe. This test will allow us to determine the evolution of hardness in the longitudinal and transverse directions of the welded joint. The objective of our study is based on the characterization of the processes controlling the mechanical behavior of steel pipes (type S235) with a thickness of 2.2 mm and an outside diameter of 70.70 mm, welded by HF induction. The analysis shows the existence of very diverse microstructures in the studied welded joint.
محضر اجتماع المجلس العلمي للكلية
(2022-07-21)
محضر اجتماع المجلس العلمي للكلية
(2022-07-12)

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