Publications Scientifiques

Permanent URI for this communityhttps://dspace.univ-boumerdes.dz/handle/123456789/10

Browse

Has files: NoSubject: search.filters.subject.Characterization

Search Results

Now showing 1 - 4 of 4
  • No Thumbnail Available
    Item
    Synthesis, characterization and application of tetragonal BaTiO3-δ in adsorption and photocatalysis of congo red
    (Elsevier, 2023) Merrad, S.; Abbas, Moussa; Brahimi, R.; Bellal, B.; Trari, M.
    The synthesis by a simple approach of the deficient Barium Titanate BaTiO3-δ (BTO) crystallizing in a perovskite structure is reported along with the physicochemical properties. Thermal analysis (TG/DSC) was performed to elucidate the synthesis process. The X-ray diffraction (XRD), BET analysis, scanning electron microscopy (SEM-EDS) and electrochemistry were investigated. The catalyst revealed a single phase with a tetragonal symmetry obtained by treatment at 650 °C. The direct band gap (3.34 eV), obtained from diffuse reflectance spectroscopy (DRS), is assigned to the charge transfer O2-: 2p-Ti4+: 3d. The electrical characterization indicated a non-degenerate conductivity due to oxygen vacancies with an activation energy of 0.33 eV. The capacitance measurements indicated n-type behavior with a flat band potential (Efb) of − 0.43 V and a carrier concentration (ND) of 3.90 1018 cm−3. The photocatalytic process was elucidated by the electrical impedance spectroscopy (EIS). The performance of BTO was assessed by a combination of the adsorption of Congo Red (CR) followed by its degradation under UV light. The photodegradation kinetic was well fitted by a pseudo-first-order model with an abatement of 50% and 91% under UV and solar lights respectively. Different scavengers were used to evaluate the reaction mechanism and the radicals O2•- are the main reactive species of the CR oxidation. Four regeneration cycles demonstrated the catalyst stability. A degradation mechanism was established based on the scavengers effect
  • No Thumbnail Available
    Item
    Chemical characterization of asphaltenes deposits from Hassi Messaoud field
    (Elsevier, 2022) Behnous, Dounya; Bouhadda, Youcef; Moffatt, Brian; Zeraibi, Noureddine; Coutinho, João A.P.
    The precipitation and deposition of asphaltenes are complex phenomena that reduce the efficiency in oil production operations. In this study, spectroscopic and thermal methods were used for the characterization of asphaltene samples extracted from deposits belonging to different locations in the Hassi Messaoud field. Structural parameters and the chemical structure of the studied asphaltenes were determined using 13C solid nuclear magnetic resonance (NMR), X-ray diffraction and Raman spectroscopy. The thermal behavior of the asphaltenes studied was examined using differential scanning calorimetry. The results obtained suggest that island is the predominent architecture for the asphaltenes studied with an average of 7 to 8 fused rings and aliphatic length chain of about 3–4 carbons. The number of aromatic sheets in a stacked cluster (N) is between 7 and 8 sheets. The aromatic sheet diameter of the four samples ranges from 12.18 to 15.52 Å with an average interlayer distance between aromatic sheets of 3.52 Å and an average interchain layer distance of 4.48 Å
  • No Thumbnail Available
    Item
    Characterization of the interface of a Non-Ferrous dissimilar realized by rotary friction welding
    (Springer, 2021) Mebtouche, A.; Bezzazi, Boudjema; Ramou, N.; Aboudi, D.; Faci, Y.; Latef, M.
    The need for assembly between dissimilar materials often arises in complex industrial applications. It avoids problems inherent in conventional welding. Therefore, in this study the performance of welded joints developed using a rotary friction welding machine, between Cu/Al, are characterized. The interface of the welded assembly of dissimilar copper Cua1 and AA2014 aluminum, consists of several intermetallic compounds mainly CuAl2, CuAl and Cu9Al4. Dendrites have been revealed, this structure is known to be the result of solidification. While rotary friction welding is done at the solid state. In this work, we seek to know the phenomena that take place during the entire process and in the creation of the interface. This article presents the study of the Al/Cu interfacial structure of welded joints made by rotary friction in a modified cycle with two steps
  • No Thumbnail Available
    Item
    Seismic attributes in reservoir characterization: an overview(Review)
    (Springer link, 2021) Oumarou, Sanda; Djeddi, Mabrouk; Tabod Charles, Tabod; Jean, Marcel; Ngos III, Simon; Jean Marcel, Abate Essi; Kamguia, Joseph
    The present study focuses on a literature review using seismic attributes in the characterization of hydrocarbon reservoirs. This work consists of examining the contribution of seismic attributes in the characterization of reservoirs. With this, it is necessary to identify and list the attributes involved in analyzing the reservoirs and their degree of involvement in the characterization of the hydrocarbon accumulation zones. The approach used is to classify attributes according to their levels of intervention as the attributes that circumscribe hydrocarbon accumulation zones such as instantaneous frequencies. Thus, the attributes which make it possible to analyze the seismic facies must be enumerated to determine the type of hydrocarbons. The aim of this work is not only to review the literature on the use of seismic attributes in the characterization of reservoirs but also to expose the limitations of these attributes in the study of reservoirs to search for the most adapted attributes that have never been used in reservoir analysis. As a result, several seismic attributes used in reservoir characterization will be evaluated while demonstrating their strengths and limitations to consider either the combination of certain attributes or the experimentation of new attributes in deepening the knowledge on the study of reservoirs. This work will contribute to a more sophisticated study in this domain