Publications Internationales

Permanent URI for this collectionhttps://dspace.univ-boumerdes.dz/handle/123456789/13

Browse

Subject: search.filters.subject.Potential

Search Results

Now showing 1 - 4 of 4
  • No Thumbnail Available
    Item
    Structural, morphological, and magnetic properties of electrodeposited coNi thin films on the FTO substrate
    (Springer, 2022) Boulegane, Ala; Guittoum, Abderrahim; Laggoun, Ali; Boudissa, Mokhtar; Hemmous, Messaoud
    CoNi films were elaborated by electrodeposition onto FTO substrates using a chloride bath with a metallic ion molar ratio [Co2+]/[Ni2+] equals 1/1. Three samples were elaborated for different potentials ranging from −1.6 to −1.5 V. The structure and the morphology of CoNi films were studied using X-ray diffraction (XRD), scanning electron microscopy (SEM), and atomic force microscopy (AFM). The chemical compositions are obtained using energy dispersive X-ray (EDX) and the magnetic properties were studied using a vibrating sample magnetometer (VSM). From X-ray diffraction, we have shown the presence of the FCC phase of CoNi binary alloy with a well-pronounced texture along the < 111 > , < 200 > , and < 220 > planes for all samples. We have found that the applied potential has an influence on crystallite sizes. Besides, a moderate change in the lattice parameter has been observed with increasing applied potential. The AFM images show that the applied potential changes the morphology and the surface roughness of CoNi films. In addition, the SEM images confirm the granular morphology of CoNi deposits and show a good relationship between voltage and grain size. The EDX spectrums confirm the deposition of the cobalt and the nickel on the FTO substrate and show the precedence deposition of Co compared with Ni. The extracted coercive field Hc and squareness from the hysteresis loops explained the good correlation between the magnetic and structural properties of CoNi thin films
  • No Thumbnail Available
    Item
    Wind flow simulation and characteristics prediction using WAsP software for energy planning over the region of Hassi R’mel
    (Taylor and Francis, 2021) Meziane, Fares; Chellali, Farouk; Mohammedi, Kamal; Nouicer, Ilyes; Kabouche, Nourdine
    In this study, we analyzed the wind potential of Hassi R’mel (Algeria) under the Wind Atlas Analysis and Application Program (WAsP) environment, using data measurements at a height of 10 m provided by the National Office of Meteorology (NOM) over the period of 14 years (2003–2017). The results are used as input for predicting wind characteristics (speed and direction) for four other sites covering the studied region where the measurement stations are not available. The pre-feasibility study of large-scale energy and hydrogen production focuses on four sites, namely Telghemt, Delaa, Bouzbier, and Bellil. Two different wind turbine models, Bonus B54 and Nordex N100 with a rated power of 1000 kW and 2500 kW, respectively, were selected. The study pointed out that the region of Hassi R’mel has an important wind potential with an annual mean wind speed of 6.73 m/sec and power density of 365 W/m2 at 10 m. The maximum of energy and hydrogen produced occurs for the site of Hassi R’mel with 12.41 GWh/yr, and 177.37 tons H2/yr, with minimal costs of 5.5 c$/kWh, and 18.42 $/kg H2 respectively using Nordex N100 wind turbine at 100 m. Similarly for the site of Bellil where the maximum of energy and hydrogen production of 5.395 GWh/yr, and 77.08 tons H2/yr were obtained with minimal costs of 5.06 c$/kWh, and 17.12 $/kg H2 respectively using Bonus B54 wind turbine at 60 m. Therefore, the high rate of carbon dioxide (CO2) emissions avoided by N100 was 5428.2 tons CO2/kWh for Hassi R’mel, and 2359.2 tons CO2/kWh for Bellil using the B54 wind turbine
  • No Thumbnail Available
    Item
  • No Thumbnail Available
    Item
    Verification of Levich law. determination of hydrogen currents accoring to temperature and polarization potential during calcareous deposition
    (2011) Ghemmit-Doulache, Naima; Khireddine, H.; Si Salah, D.
    The complexity of calcareous deposits processes in a marine environment results in simultaneous effects of the following parameters: temperature, polarization potential, interfacial pH, chemical composition, etc.. The comprehension of these processes implies studies in artificial seawater and a follow-up of the parameters by voltamperometry and chronoamperometry. Calcareous deposits electrochemically are very often used to follow up the evolution of scale deposition in desalination circuits. Again, the scale formation is brought about by electrochemical reduction of dissolved oxygen. The hydroxyl ions formed on the metallic surface engender a rise of interfacial pH which causes calcareous deposition (CaCO3 and Mg(OH)2). This reaction goes with reaction of hydrogen evolution which could disrupt the formed deposit. A study is carried out in a solution of seawater ASTM without calcium and without magnesium (so that the deposit will not be formed) on a titanium rotating disk electrode monitored between 300 and 1000 rpm. Study shows that Levich criterion is checked for the four values of selected potential on the diffusion plateau and a very cathodic polarization potential and a high temperature favors hydrogen current rate