Chimie

Nombre total de résultats : 150
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Elaboration et caractérisation du revêtement anti corrosion par la voie sol-gel

 (2018)
Article de conférence

La méthode sol-gel est utilisée dans les revêtements anticorrosifs, les nanomatériaux, ...Elle se base principalement sur l'élaboration d’un nouveau matériau d’’une faible épaisseur qui peut améliorer Les propriétés physique, chimique, structurale et la résistance à la corrosion des matériaux. Des couches en SiO2 ont été déposé sur l'alliage d'aluminium et l'alliage de magnésium par la technique sol-gel ( Dip Coating).Le comportement électrochimique des alliages métalliques revêtus a été évalué un environnement marin de 3% de NaCl par spectroscopie électrochimique d'impédance (EIS) et par polarisation potentiodynamique.Les caractérisations microstructurales, morphologiques ainsi que la résistance à la corrosion des revêtements élaboré sont été effectué par, microscope électronique à balayage (MEB), la polarisation potentiodynamique et les techniques d’impédance électrochimiques(EIS), des mesures de dureté des revêtements a été effectuées par Nano indentation.Voir les détails

Mots clés : matériaux, corrosion, revêtement, sol gel

Simulation et modélisation des incertitudes

 (2018)
Article de conférence

Sensitivity analysis and uncertainty estimation are of major importance for the declaration of conformity of finished products. Models must be sought to analyze the test data. The main objective of this work is to establish reliable models to analyze our experimental data and validate them. So we have studied and used the Monte Carlo and Bootstrap simulation methods, we have been able to realize programs that calculate the uncertainty according to the ISO 8466 standard on X-ray fluorescence spectrometer samples from the URASM CRTI chemical analysis laboratory. Programs and interfaces are made with Matlab (GUI).Voir les détails

Mots clés : Simulation; uncertainties; Monte carlo; Bootstrap; calibration

Simulation et modélisation des incertitudes lors de l’étalonnage d’un spectromètre d’analyse chimique de fluorescence

 (2018)
Article de conférence

Sensitivity analysis and uncertainty estimation are of major importance for the declaration of conformity of finished products. Models must be sought to analyze the test data. The main objective of this work is to establish reliable models to analyze our experimental data and validate them. So we have studied and used the Monte Carlo and Bootstrap simulation methods, we have been able to realize programs that calculate the uncertainty according to the ISO 8466 standard on X-ray fluorescence spectrometer samples from the URASM CRTI chemical analysis laboratory. Programs and interfaces are made with Matlab (GUI).Voir les détails

Mots clés : Simulation; uncertainties; Monte carlo; Bootstrap; calibration

ANALYSE PHYSICO-CHIMIQUE DE LAITIER DE HAUT FOURNEAU PAR SPECTROSCOPIE INFRAROUGE (IR) ET DIFFRACTION DE RAYON X (DRX)

Ouahida Khireddine, Toufik CHOUCHANE, Amel Bendjama, Sana Chibani, Samira TLILI (2018)
Article de conférence

L’industrie sidérurgique génère une production fatale de matières secondaires constituées de produits de réactions résultant de son activité de production d’acier. Ces matières secondaires sont désignées communément par les coproduits sidérurgiques tels que : les laitiers de haut fourneau. Les principales propriétés physiques de laitier de haut fourneau (La densité et la surface spécifique). Les échantillons ont été caractérisés par différentes techniques d’analyses parmi nous citons : la diffraction des rayons X et la spectrométrie infrarouge à transformée de Fourrier. Les diffractogrammes obtenus sur les échantillons des laitiers caractérisent la phase vitreuse et quelques raies de faible intensité représentant les composés cristallisés. Lors de l’analyse des poudres par spectrométrie infrarouge IR, Le spectre a montré des bandes identifiées, telles que le les liaisons Al-O, Ca-O, et Si-O qui se caractérisent par les bandes de vibration à environs 634, 1793, 956 cm-1 plus la présence des carbonates caractérisés par la bande 879 cm-1.Voir les détails

Mots clés : Déchets sidérurgiques, Caractérisation chimique, DRX, IR, laitier

Synthesis and characterization of Nickel oxide (NiO) thin films

Bouhank .A, Serrar.H, Bellal .Y (2018)
Article de conférence

For the synthesis of Nickel oxide as thin films, with the spray pyrolysis technical as a chemical method of deposit, on ordinary glass substrates heated to a fixed temperature of 500 °C. we use Nickel nitrate hexahydrate (99.5 %, Aldrich) as source precursor, dissolved in distilled water. Nickel oxide is a p-type semiconductor, is an important material because of its large direct optical gap between 3.6 and 4.0 eV; and easy to deposit in thin layers by many techniques, such as sol-gel and spray pyrolysis. Diagrams of X-ray diffraction (XRD), to confirm the formation of the phase have characterized the structure of the films deposited by the pyrolysis spray technique. Where they showed that NiO are nanoparticle films and have preferred orientations according to (111) and grain sizes in the range of 15 to 48 nm. The surface morphology, absorption domain, molecular vibrations were characterized by scanning electron microscopy (SEM), UV-Visible Spectroscopy and Raman spectroscopy.Voir les détails

Mots clés : NiO, Raman, UV-Visible Spectroscopy, XDR

A Copper Oxide (CuO) Thin Films Deposited by Spray Pyrolysis Method

Y. Bellal, A. Bouhank, H. Serrar, T. Tüken, G. Sigircik (2018)
Article de conférence

A simple and low-cost procedure (spray pyrolysis) was used to elaborate copper oxide thin films on ordinary glass substrates. A copper nitrate was used and dissolved in two different solutions (Water, Methanol) S1 and S2 respectively in order to obtain an equal concentration;CS1, S2= 0.5M.The spray pyrolysis deposition made at fixed temperature T= 500°C and different volumes of S1 or S2 on the glass substrates. The X-ray diffraction (XRD), scanning electron microscopy (SEM) and UV-vis spectrophotometry were used to determinate the structural, morphological and optical properties of CuO thin films. The X-ray diffraction patterns confirm the presence of the polycrystalline phase of CuO as monoclinic crystal structure with preferential orientation along (110), (002), (111), (200) and (020). Their optical band gaps ranged from 3.95 to 4.02eV for thin films made with S1, and from 1.6 to 1.95eV for thin films made with S2 with a high absorbency in the visible region, which is in agreement with the values of the literature.Voir les détails

Mots clés : Copper oxide, Thin films, Spray pyrolysis, Band Gaps, XRD, SEM.

Elaboration and Characterization of Copper Oxide (CuO) Thin Films Deposited bythe Spray Pyrolysis Method

Y. Bellal, A. Bouhank, H. Serrar (2018)
Article de conférence

In this work, a copper oxide thin films were deposed by a simple and inexpensive technique (spraypyrolysis) on ordinary glass substrates at a fixed temperature T=500°C. and differentconcentration of precursor 15, 30 and 45 ml made with H2O like solvent.The structural, morphological and optical properties of thin films of CuO were studied by X-raydiffraction (XRD), scanning electron microscopy (SEM) and UV-vis spectrophotometry. The Xray diffraction patterns confirm the presence of the polycrystalline phase of CuO as monocliniccrystal structure with preferential orientation along (110), (002), (111) and (020). Their opticalband gaps ranged from 3.95 to 4.02eV with a high absorbency in the visible region.Voir les détails

Mots clés : Copper oxide, Thin films, Spray pyrolysis, Band Gaps, XRD, SEM

Chemical Synthesis and Characterization of nickel oxide as semiconductor thin film and doping agent of titanium dioxide

A.BOUHANK, H.Serrar, Y.BELLAL (2018)
Article de conférence

Nickel oxide (NiO) is a p-type semiconductor , is an important material because of its large direct optical gap between 3.6 and 4.0 eV , of its chemical stability and magnetic device , and easy to deposit in thin film by several chemical techniques. However, it used as a dopant of titanium dioxide.NiO thin films were deposited by spray pyrolysis on ordinary glass substrates heated to a fixed temperature of 500 °C, from a nickel nitrate hexahydrate as a precursor dissolved in distilled water.Titanium dioxide is doped with deferent percentage of NiO, this latter was elaborate with the sol-gel method.The both type of thin film, were characterized by several techniques, Such as X-ray diffraction, scanning electron microscopy, optical absorption, Atomic force microscopy , and Raman spectroscopy.Voir les détails

Mots clés : NiO, TiO2, Dip coating, semiconductor

Electrochimical oxidation of glucose by Ni-Fe nanoparticiles dispersed on polyaniline thin films

D. Lakhdari, A. Guittoum, O.Belgherbi, N. Benbrahim (2018)
Article de conférence

In this work we describe the electrodeposition of Ni–Fe nanostructures on polyanilyne (PAni) as templates. The conditions and parameters influence in the morphology and electrochemical activity of the electrodeposited Ni–Fe nanoparticles.The electrocatalytic properties of Ni–Fe/polyanilyne-modified electrode toward the glucose oxidation were analyzed via cyclic voltammetry and amperometry. The studies showed that Ni–Fe /PAni electrode displayed the highest electrocatalytic activity, attributed to the high density of Ni–Fe nanoparticles deposited on the polyanilyne vibreuse nanotubes support.Voir les détails

Mots clés : Ni–Fe nanoparticles, glucose, Polyanilne, cyclic voltammetry, Electrocatalytic Oxidation

A Copper Oxide (CuO) Thin Films Deposited by the Spray Pyrolysis Method

BELLAL YOUCEF, BOUHANK Antar, SERRAR Hacene (2018)
Article de conférence

A simple and low-cost procedure (spray pyrolysis) were used to elaborate copper oxide thin films on substrates in ordinary glass. a copper nitrate was used and dissolved in two different solutions (Water, Methanol) S1 and S2 respectively in order to obtain an equal concentration;CS1, S2= 0.5M.The spray pyrolysis deposition made at fixed temperature T= 500°C and different volumes of S1 or S2 on the glass substrates. The X-ray diffraction (XRD), scanning electron microscopy (SEM) and UV-vis spectrophotometry were used to determinate the structural, morphological and optical properties of CuO thin films. The X-ray diffraction patterns confirm the presence of the polycrystalline phase of CuO as monoclinic crystal structure with preferential orientation along (110), (002), (111), (200) and (020). Their optical band gaps ranged from 3.95 to 4.02eV for thin films made with S1, and from 1.6 to 1.95eV for thin films made with S2 with a high absorbency in the visible region, which is in agreement with the values of the literature.Voir les détails

Mots clés : Copper oxide, Thin films, Spray pyrolysis, Band Gaps, XRD.