(JNTM) مجلة التكنولوجيا الجديدة والمواد

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1‐formyl‐3‐phenyl‐5‐aryl‐2‐pyrazoline Derivatives As Corrosion Inhibitors Of Steel In Acidic Medium
(Oum-El-Bouaghi University, 2018) Sid, Assia; Selatnia, Ilhem
Quantum chemical calculations and Molecular dynamic (MD) simulations were performed on two synthesized pyrazoline derivatives namely: 1‐Formyl‐3‐phenyl‐5‐(4‐methylphenyl)‐2‐pyrazoline (P1) and 1‐Formyl‐3‐phenyl‐ 5‐(4‐chlorophenyl) ‐2‐pyrazoline (P2) in order to study their reactivity and adsorption behavior towards steel corrosion. Quantum chemical parameters such as EHOMO, ELUMO, energy gap (ΔE), fraction of electron transfers (ΔN) and Fukui index have been studied. Moreover, Molecular dynamics simulation is performed to simulate the best adsorption configuration of the investigated inhibitors on Fe (1 1 0) surface. DFT results indicate that the active sites of the molecules were mainly located on the pyarazoline ring and on the carbonyl group. The binding strength of the studied inhibitor molecules on Fe surface follows the order P1>P2, which is in good agreement with the results of quantum chemical calculations.
A Comparative Study Of The Structural, Magnetic And Magnetocaloric Properties In Pr0.6la0.1m0.3mno3 Manganites (m = Ca, Ba And Mg)
(Oum-El-Bouaghi University, 2016) Zouari, S.; Hlil, E. K.; Kahn, M. L.; Ellouze, M.; Elhalouani, F.
The Comparaison of the structural, magnetic and magnetocaloric properties of Pr0.6 La0.1M0.3MnO3 (M = Ca, Ba and Mg) compounds have been studied using X-ray diffraction (XRD) and magnetic measurements. Our compounds have been prepared using the Sol-Gel method reaction at room temperature. Rietveld refi nements of the X-ray diffraction patterns reveal that our compounds are single phase and crystallize in the orthorhombic system with Pnma space group. Magnetization measurements versus temperature in a magnetic applied fi eld of 0.05T indicate that samples display a ferromagnetic (FM) - paramagnetic (PM) transition with increasing temperature. The Curie temperature TC is found to be 94 K, 39 K and 64 K for M = Ca, Ba and Mg, respectively. From the magnetization data as a function of magnetic applied fi eld, we have determined the associated magnetic entropy change, the maximum of the magnetic entropy ǀ ǀ and the relative cooling power (RCP) for Pr0.6 La0.1M0.3MnO3 (M = Ca, Ba and Mg) compounds. In the vicinity of TC and in a magnetic applied fi eld of 2 T, ǀ ǀ reached, the values of 0.87 J/kg K, 1.43 J/kg K and 0.79 J/kg K for M = Ca, Ba and Mg, respectively.
A Comprehensive Nonlinear Model For Gaas Mesfet Transistor
(Oum-El-Bouaghi University, 2013) Mellal, Saida; Azizi, Cherifa; Zaabat, Mourad; Ziar, Toufik; Kaddour, Chahrazed; Azizi, Mounir
An analytical two-dimensional (2D) model to accurately predict the channel potential and electric field distribution in sub-micron GaAs MESFET based on (2D) analytical solution of Poisson’s equation using superposition principle is presented. The results so obtained for current voltage characteristics, Transconductance and drain conductance, are presented and validated against both experimental I-V curves and various Models of the submicron MESFET GaAs. The model is then extended to predict the effects of parasitic resistances Rs and Rd, carriers mobility according to the electric fields and the edges effects on the performance. This model will allow more significant simulation of the component characteristics, with a precision improved for various conditions of Schottky barrier.
A New Drain Current I–v Model For Mesfet With Submicron Gate
(Oum-El-Bouaghi University, 2013) Azizi, Mounir; Azizi, Cherifa
In this work we present a new nonlinear approach for the calculation of the static characteristics of MESFET GaAs with submicron gate. First, we compare the results of the numerical simulations of the three main models for the MESFETs with submicron gate : Ahmed [1], Islam [2] and Memon [3] with experimental results. Then we propose a new approach that takes into account the surface states of the Schottky junction through a new mobility law for the determination of the output characteristics. The thermal effect is also represented in the mobility law. The comparison of our model with the three previous models referring to the experimental data shows that our approach gives the most accuracy result. Also, the proposed model can be used in the case of logic or analog circuits based on submicron GaAs MESFET.
A Review in machining-induced residual stress
(Oum-El-Bouaghi University, 2022) Soori, Mohsen; Arezoo, Behrooz
Due to friction, chip forming, and the induced heat in the cutting area, produced parts by using machining operations have residual stress. Residual stresses caused by machining processes have a major effect on the fatigue life of machined components, which can shorten their service life. In order to increase the performance of machined parts in real-world applications, such as fatigue life, corrosion resistance, and component distortion, residual stress should be investigated and minimized. As a result, predicting and controlling residual stresses caused by machining operations is important in terms of quality enhancement of machined parts. This paper reviews the recent achievements in the machining-induced residual stress in order to be analyzed and decreased. Different methods of the residual stress measurement Destructive Methods, Semi-Destructive Methods and Non-Destructive Test (NDT) Methods are reviewed and compared in order to be developed. In order to minimize residual stress in machined parts, the study examines the effects of machining process parameters, high-speed machining conditions, coolant, cutting tool wear, edges, and radius on residual stress. Analytical and semi-analytical modeling, numerical and FEM simulation techniques of residual stress are reviewed to include advanced methods of residual stress modeling methodology to predict residual stress in machined components. Residual stress in various alloys such as AL alloys, biomedical implant materials, hard to cut materials such as nickel-based alloys, Titanium Based Alloys, Inconel Based Alloys, and stainless-steel alloys is investigated in order to provide efficient residual stress minimization methods in machined components. It has been realized that evaluating and analyzing recent advances in published papers will contribute to develop the research field.
A simple synthesis of CuO NPs for photocatalytic applications and theirs structural and optical properties
(Oum-El-Bouaghi University, 2021) Roguai, Sabrina; Djelloul, Abdelkader
In this study, the copper nanoparticles were synthesized by simple co-precipitation method which were obtained by heating at 80°C for photocatalytic application. The microstructural characterization of the nanopowder obtained was performed using X-ray diffraction (XRD), SEM, EDS, and Infrared Spectroscopy (IR). The optical properties of nanoparticles were studied by UV-Visible spectroscopy. XRD studies demonstrated that the formation of CuO monoclinic phase and the average grain size of CuO crystallite were found to be 30 nm. The FTIR spectral analysis showed the characteristics peaks of Cu-O bond. The EDAX result indicated that there were no other elemental impurities present in the prepared CuO nanoparticles. SEM images indicate the morphology as a three-dimensional flower-like structure was successfully prepared for subsequent degradation of methylene blue (MB). With regard to the optical proprieties, the value of the bandgap energy equals 1.34 eV.
A Study Of C(v) Characteristics Of Capacitors Containing High-k Oxides And High Mobility Carriers Semi-conductors
(Oum-El-Bouaghi University, 2015) Merzougui, Amina; Latreche, Saida; Bouchekouf, Seloua
In this work, we proceeded to the analysis of C(V) characteristics of MOS capacitors (Metal-oxide-semi-conductor) with metal gates. Within the framework of the search for new materials, we have studied C(V) characteristics of structures containing high permittivity oxide (high-k)- the HfO2 in our case- to replace the ultra-thin conventional oxide layer (SiO2 ) which reaches its physical and technological limits (less than 1 nm thickness). In these same structures, the stacking of grid is deposited on a substrate with high mobility carriers (electrons and holes). In fact: The germanium (Ge) and III-V materials [1]. The obtained results were largely compared with others simulated and experimental ones.
Analysis Of Impurities Of Nd-fe-b Magnet By Nuclear Method And Recovery By Precipitation Chemical Of Nd And Pr Rare Earths
(Oum-El-Bouaghi University, 2017) Cheraitia, Kamel; Lounis, Azzeddine; Mehenni, Mohamed
Abstract The products of the new information and communication technologies (NTIC), whose life often not exceed three years, became consumables to the computer image and other waste that contains neodymium and praseodymium (rare earths). In this field of analysis of impurities, treatment and recycling of waste, we propose the recovery of elements such as neodymium and praseodymium, from the super-magnet Nd-Fe-B, Our study provides a simple process and inexpensive. The implementation scheme of our project consists in a first step in developing a plan of experience that has been made specifically to perform the optimization of operating conditions of the precipitation process. This experimental design was inspired by a statistical technique advanced design of experiments known factorial design. The flow sheet processing of recovery begins by embrittlement in liquid nitrogen (-196C) followed by dissolution in an acidic solution and precipitation of Nd as neodymium oxalate. For characterization we used the following techniques: The neutron radiography, the neutron activation analysis(NAA), the scanning electron microscope coupled with EDX and XRD. The counting of γ spectrum shows that the purity of the precipitate is higher than 99%. Then, the thermal decomposition transforms this powder to neodymium oxide. After the reduction we obtain pure neodymium
Antibacterial Effects And Fastness Properties Of Dyed Silk Fabric With Curcumin In Presence Of Organic And Bio Mordants
(Oum-El-Bouaghi University, 2017) Azarmi, Reyhaneh; Ashjaran, Ali; Azad, Islamic
Curcumin, a common natural dye used for fabric and food colorations, was used as an antimicrobial finish due to its bactericidal properties on dyed textiles. In this work, silk fabrics were treated with curcumin and mordant with inorganic salt such as ferric sulfate, aluminum sulfate, potassium dichromate and copper sulfate and biological mordant such as chitosan. The strength color and color fastness to rubbing and washing of the dyed silk fabrics in presense of organic and bio mordants were evaluated. Also antibacterial properties of treated silk fabrics against two kinds of bacteria: staphylococcus aurous and Escherichia coli were investigated. All mordant fabrics have good color strength compered to unmordant onces. The treated silk samples with chitosan in 0.6% concentrations were found to have good antibacterial potential.
Artificial Aging Effect On Precipitation And Age-hardening In An Al-zn-mg-cu Alloy
(Oum-El-Bouaghi University, 2019) Boumaza, Leila; Hadjadj, Lakhdar; Belamri, Zahira; Azizi, Assia; Benmelit, Rabia; Hamana, Djamel
In the present work, the influence of heat treatment on the mechanical properties and precipitation of the different phases in Al-Zn-Mg-Cu alloy was studied. The precipitation sequence and the mechanism of structural hardening have been followed using the differential scanning calorimetry (DSC), the microhardness measurements, the X-ray diffraction (XRD) and the scanning electron microscopy (SEM). Five calorimetric effects have been recorded and correspond to the different phases precipitating in this system of alloys and which are: the GPI zones and / or VRC (or GPII), the intermediate η' phase and the equilibrium η phase with a suspicion concerning the existence of T and S phases. Microhardness measurements of the aged state at 226 °C confirm the existence of two types of phases: the metastable η’ phase and the equilibrium η phase (MgZn2). The appearance of the first precipitates was followed by SEM. The fine precipitates become larger (holdings at 243 and 266 °C) and the equilibrium η phase continues to grow inside and on the grain boundaries to become a large spherical and/or lamellar precipitate. The X-ray diffraction confirmed that only the equilibrium η phase was observed in this type of alloy.
Aspenplus Based Simulation For Waste Heat Recovery In Cement Industries
(Oum-El-Bouaghi University, 2019) Redjeb, Youcef; Djerrafi-kaabeche, Khatima; Saouli, Ouacil
Cement manufacturing is a highly energy intensive process, which resulting a large loss of energy at the level of the different plants, in other way the loss of energy in the form of heat is very significantly at the level of the cooler. This work focus on direct waste heat recovery, where tertiary air was recovered to the preheater, for this study a process model of the preheater, the kiln, and the cooler is developed, using Aspen Plus simulation software, and the model is verified against measured data from industry. This paper presents the influence of the recovery of the waste heat and the natural gas feed on the clinker production and the energy consumption. Results show that the recovery of the tertiary air make the clinker production rise by about 30% and the energy consumption reduced by about 20%. The variation of the flow input value of the natural gas resulted in a positive relationship between natural gas flow and clinker production, and an inverse relationship between the natural gas feed and energy consumption. In the other hand the increase of the natural gas flow resulting an augmentation in the clinker production, and the reverse results for the consumption of energy.
Assessing Vulnerability Of Groundwater With God Model: A Case Study In Oran Sebkha Basin - Algeria
(Oum-El-Bouaghi University, 2017) Boualla, Nabila; Benziane, A.
The vulnerability of groundwater is a relative, non-measurable and dimensionless property, which is based on the concept that some land areas are more vulnerable to groundwater contamination than others. Most groundwater vulnerability modeling has been based on current hydrogeology and land use conditions. However, groundwater vulnerability is strongly dependent on factors such as depth to water, recharge and land use conditions that may change in response to future changes in climate and/or socio-economic conditions. The evaluation of the aquifer vulnerability is one of the tools supporting decision making related to aquifer protection. This study is a help approach to protect and prevent pollution of the Oran Sebkha basin. It discusses the creation of a groundwater vulnerability map. This area of the aquifer is essentially occupied by agricultural areas characterized by an important use of chemical fertilizers, which are in addition to the discharge of industrial zones. The water resources are becoming increasingly scarce, over-exploited, poorly distributed and most especially polluted. Information on the hydraulic confinement, overlying strata in terms of their lithological character and depth to groundwater table that is affect and control groundwater contamination were incorporated into the GOD model, to produce groundwater vulnerability maps. The final map shows interesting results and stresses the need for the GIS to test and improve on the groundwater contamination risk assessment method. It was found that the studied water is characterized by a low to very high degree of vulnerability. A moderate vulnerability in area covering 71.5% of the extension of the shallow aquifer.
Assessment Of Surface Water Quality In The Beni Haroun Dam Algeria Using X-ray Fluorescence Spectrometry After Preconcentration
(Oum-El-Bouaghi University, 2020) Aouati, Mohamed Khelil; Laidoudi, Mouloud; Cheurfi, Wassila; Baghriche, Abdelfeteh; Bougherara, Hassina; Kebabi, Brahim
X-ray fluorescence spectrometry after preconcentration of the water of Beni Haroun dam (BHD), Mila, Algeria. Has carried out with two different methods which yielded the contents as following Na, Mg, Al, Si, P, S, Cl, K, Ca, Ti, V, Cr, Mn, Fe, Ni, Cu, Zn, Ga, As, Se, Br, Rb, Sr, Y, Zr, Mo, Cd, Ba and Pb. The first method is preconcentration at evaporation temperature (PET), this method based on the recovery of limestone, and it is simple and cheaper. Whereas the second preconcentration method is based on the absorption of cations on Amberlite XAD -7 resin (AXAD-7R). The effect of certain parameters such as pH, temperature, conductivity, Nitrate dosage, chemical oxygen demand (COD) and limit of detection has been studied. The detection limits were reached for Na, Mg, Al, Si, P, S, Cl, K, Ca, Ti, Mn, Fe, Zn, As, Br, Sr, Zr, In and Ba, during the four seasons of the year 2018. In this Water, the X-ray diffraction analysis showed the existence of the following phases: Calcium Carbonate Hydrate: CaCO3 H2O, Sodium Chloride NaCl and silicon dioxide SiO2. The principal component analysis (PCA) has been studied. The matrix of correlation between trace element and the PCA indicates that they come from similar sources. This explains the anthropogenic contributions of agricultural pollution by runoff water, discharges of domestic water and soil erosion. Regular monitoring of heavy metals in Beni Haroun dam water has recommended avoiding any risk of excessive accumulation.
Biodegradable poly(lactic acid)/kaolin clay nanocomposites prepared by melt mixture
(Oum-El-Bouaghi University, 2022) Zenasni, M. A.; Meroufel, B.; Georgeb, B.
Biodegradable polymer nanocomposites of poly (lactic acid) (PLA) and several organically modified kaolin, namely, Kaolin raw (K08), kaolin APTES (KS) and kaolin CTAB (KC) were prepared by melt compounding using a Brabender mono-screw extruder. An exfoliated morphology was observed using both X-ray diffraction analysis (XRD) and scanning electron microscopy (SEM) for the combination of PLA with kaolin raw, with kaolin CTAB (the kaolin modified with a quaternary ammonium salt) and with kaolin APTES (the kaolin modified with 3-aminopropyltriethoxysilane). Further studies were carried out to compare the properties of the nanocomposites with those of the neat PLA. Thermal stability of the nanocomposites was studied using thermogravimetric analysis (TGA).
Breves Generator Of Pulses At Different Flow Rates (40 Ghz, 80 Ghz And 160 Ghz)
(Oum-El-Bouaghi University, 2017) Hamouda, Amar; Saouchi, Kaddour
Abstract This work presents the realization by simulation a breves generator of pulse has different flow rates (40 GHz, 80 GHz, 160 GHz). In a first step, we have realized the source of short pulse train at 40 GHz by the non-linear compression of a sinusoidal flapping through a process of mixtures four multi-wave, using the Mach-Zehnder modulator and optic isolator simple. In a second step, the pulse train obtained is then fiberized to reduce the duty ratio of 1/5 to 1/16. In a third step the train obtained encoded then multiplexed to a throughput of 80 Gbit/s. In the last step, we present the re-coding and re-multiplexing again, in order to obtain a rate of 160 Gbit/s, in order to perform simulation a brief pulse generator, simple, easy implementation, is not expensive, in three outputs of different rates, stable and without jigs.
Capacitance–frequency (c-v–f) And Conductance–frequency (g-v–f) Characteristics Of Au/n-gan Freestanding Schottky Structure
(Oum-El-Bouaghi University, 2018) Mazari, Halima; Ameur, K.; Khelifi, R.; Mansouri, S.; Benseddik, N.; Benamara, Z.; Boumesjed, A.; Benyahya, N.; Marie, P.; Ruterana, P.; Monnet, I.; Bluet, J. M.; Bechare, R.
In this paper, we have studied Au/n-GaN freestanding Schottky structures. The growth technique of GaN used is the HVPE (Hybrid Vapor Phase Epitaxy) method. The frequency dependent capacitance–voltage (C–V–f) and conductance–voltage (G–V–f) characteristics of Au/n-GaN freestanding/Ag Schottky diodes has been investigated in the frequency range of 100 Hz–1MHz at room temperature. The higher values of C and G at low frequencies were attributed to the native oxide layer thickness and surface states. From the C–f and G–f characteristics, the energy distribution of surface states (Nss) and their relaxation time (s) have been determined in the energy range of (Ec-0.648) eV– (Ec-1.35) eV taking into account the forward bias I–V data. The values of Nss and ss change from 6.18×1013 eV-1 cm-2 to 9.37×1012 eV-1 cm-2 and 6.3×10-4 s to 3.6×10-7 s, respectively.
Changes Of Thermal Conductivity,optical Conductivity, And Electric Conductivity Of Porous Silicon With Porosity
(Oum-El-Bouaghi University, 2013) Alfeel, Faten; Awad, Fowzi; Qamar, Fadi
Porous silicon (PS) was prepared by electrochemical etching method. Mirage effect in transverse photothermal deflection PTD ( skimming configuration) was used to determine thermal conductivity the experimental results of PS thermal conductivity was compared with theoretical results they were almost the same. Optical extinction coefficient and absorption coefficient were calculated from transmittance T and reflectance R curve which measured with UV-Vis-NIR Spectrophotometer, and they were used to calculate the optical conductivity and electric conductivity from the Shankar and Joseph equations, and optical conductivity and electric conductivity were studied with porosity in porous silicon.
Channel Drop Filter Based On Coupled Cavity In Photonic Crystals
(Oum-El-Bouaghi University, 2014) Bendjelloul, Rahima; Bouchematand, Touraya; Bouchemat, Mohamed
In this paper, a five channel drop filter has been designed in a two dimensional photonic crystal with high dielectric rods in air. Each channel consists of a photonic crystal coupled cavity waveguide with double cavities combined with a line defect waveguide. Desired wavelengths are selected by setting different radii of the two point defects in the photonic crystal coupled cavity waveguides. Defect rods placed at the same channel have an identical radius. The performance of the designed filter has been numerically calculated using the finite difference time domain method. In the designed structure, higher efficiencies in all channels have been achieved.
Characterization Of Bioactive Compounds In South-western Algeria Propolis Samples
(Oum-El-Bouaghi University, 2017) Berroukche, Abdelkrim; Terras, M.; Slimani, M.; Denai, I.
The prepared hydro-alcoholic extract of propolis samples, which are harvested in Rebahia (Saida, Algeria), were analyzed by gas chromatography-mass spectrometry to provide 50 volatile bioactive compounds. The major compounds had been found, to know: Terpenoids (spathulenol 2.01 %, 1-dotrontanol 1.25 and trans-2-hexen-1-ol 1.03 %), Polyphenols (carvacrol 0.71 % and thymol 0.49 %) Hydrocarbons (1,4-diethyl cyclohexane 8.22 % and 1-docecane 12.13 %) and organic acids (9,12-octadecadienoic acid 1.27 %).
Characterization Of Biosourced Materials Cement- Date Palm Fibers
(Oum-El-Bouaghi University, 2020) Bellel, Nadjoua; Boufendi, Toufik
The objective of this work is the use of biosourced materials in wall coverings to improve thermal insulation. This study may contribute to the development of sustainable building and effective renovation. The natural fibers used in this work as reinforcement are the fibers of the date palm clusters collected from Biskra (Algeria). The used matrix is cement (Portland cement pozzolan CEM II / A-P 42.5 N) supplied by the cement company of Hamma Bouziane, Constantine, Algeria. Samples prepared with four different weight fractions (0, 1, 3 and 5%) of DPF are tested after grinding. The characterization of these samples was performed by Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). FTIR and XRD analysis show that the addition of fibers does not affect the chemical composition of the matrix. The DSC and TGA results show that the addition of date palm fibers has an impact on the thermal properties of the matrix. According to the obtained results, composites containing date palm fibers have in practice excellent properties that can compete with building materials.

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