Publications Internationales

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    Modeling and Optimization of the Compressive Strength of an Alkali-Activated Material Using a Mixed Full Factorial Design
    (2025) Arezki, Sarri; Oualit, Mehena; Cherfi, Abdelhamid
    The aim of the present work is to carry out a technical study on blast furnace slag based-alkali-activated binders, using design of experiments methodology. A four-factor, mixed-level (two and three) full factorial design was employed to evaluate and model the significance and interactions of 4 independent factors on the compressive strength: curing environment, activator type (Alkali silicate (AS) and Alkali hydroxide (AH)), activator content and curing time. The experimental compressive strength data were adequately fitted by empirical models with determination coefficients (R2) of 0.89 and 0.93 for AS and AH activators, respectively. The most significant effects of factors on the compressive strength are classed according to this order: Curing time > Activator to precursor mass ratio > Curing temperature for the AS case and Curing temperature > Activating solution concentration > curing time, for the AH case. The most favorable situation corresponding to maximum compressive strength is obtained with a minimum curing temperature of 20 °C, an activator-to-precursor mass ratio of 0.42, and a maximum curing duration of 28 days, for a desirability value of 0.95, in the case of the AS activator. When using the AH activator: a Desirability function-based optimization targeting a compressive strength above 50 MPa showed that this could be achieved beyond 16 days of curing, with a minimum concentration of the alkaline solution worth 5M (considering its corrosive nature), and a medium temperature representative of North African countries (≈ °C), for a desirability value of 0.35.
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    BiMnO3 thin films synthesized by sol-gel method: Efficient photocatalytic dye degradation and hydrogen production under sunlight and visible light
    (Elsevier, 2026) Allouane, Ouiza; Toubane, Mahdia; Tala-Ighil, Razika; Beldjoudi, Nadir; Ayouz, Katia; Chabira, Fares; Boudinar, Salem; Tazerout, Mohand; Douali, Redouane
    In this work, BiMnO3 (BMO) thin films with different thicknesses (3, 5, 7, and 9layers) were successfully fabricated on glass substrates via the dip-coating technique. These BMO thin films were characterized using various techniques. X-ray diffraction analysis reveals that the as-deposited films exhibit a monoclinic phas. The crystallite size varies from 17.79 to 9.09 nm, while the roughness increases from 13.97 to 54.70 nm as the film thickness increases. UV–Visible spectroscopy measurements indicate an increase in light absorption with increasing film thickness, rising from 0.53 for 3 layers to 0.74 for 9 layers. DFT calculations indicate a direct band gap of 1.97 eV, in good agreement with the 1.62–1.81 eV values obtained from the Tauc method. BMO thin films exhibit high photocurrent densities compared to literature values, reaching 11.1 mA/cm² under visible light. The photocatalytic degradation of methylene blue (MB) by the BMO thin films increased with thickness, reaching ∼94% after 180 min under sunlight. This work will promote the development of highly efficient BMO, highlighting its potential for environmental applications
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    EFFECT OF STEEL FIBERS ON THE RHEOLOGICAL AND MECHANICAL PROPERTIES OF SELF-COMPACTING CONCRETE WITH TUFF POWDER
    (Fundatia Serban Solacolu, 2026) Naadia, Tarek; Gueciouer, Djamila; Ghernouti, Youcef; Mansour, Mali̇Ka Sabri̇a
    This experimental study focuses on the development of a steel fiber-reinforced self-compacting concrete (SFSCC) incorporating tuff powder as a local mineral addition. Five mixes were evaluated to assess the influence of fiber dosage on both fresh and hardened properties. The incorporation of steel fibers leads to reduced workability and longer flow times but significantly enhances the stability of the mix by minimizing segregation risks. Mechanically, the addition of fibers results in a marked improvement in flexural strength, with gains exceeding 40% at the highest fiber content. Ductility is substantially increased, reflecting a better ability to absorb post-cracking energy. In contrast, compressive strength shows only a moderate increase, around 11%, confirming that the main contribution of fibers lies in flexural behavior and toughness. The porous texture and pozzolanic activity of the tuff promote strong fiber–matrix bonding, contributing to improved cohesion and crack control. Overall, the findings highlight the feasibility of producing a high-performance, ductile, and stable self-compacting concrete using local resources, offering a sustainable and efficient solution for modern construction needs. © (2025), (Fundatia Serban Solacolu). All rights reserved.
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    Enhancing the Reliability of Fault Diagnosis in Lithium-Ion Batteries Using a Hybrid Model-Based and Machine Learning Approach
    (Institute of Electrical and Electronics Engineers, 2026) Maaradji, Taha Mohamed Abdelatif; Alem, Said; Gravante, Emanuele; D'Arpino, Matilde; Rizzoni, Giorgio
    Lithium-ion batteries (LIB) are essential for electric vehicles (EV) and renewable energy storage, and their safe, reliable, and efficient operation is critical. As their use grows, robust fault diagnosis becomes key to maintaining availability and performance. A major challenge is that many battery faults exhibit similar patterns, making it difficult to distinguish and isolate specific fault types. This paper presents a hybrid approach that combines model-based methods with data-driven techniques to improve the safety and reliability of LIB systems. The proposed diagnostic architecture uses structural analysis (SA) to identify analytical redundancy for fault detection and isolation (FDI), while Extended Kalman Filter (EKF) algorithms generate residuals that capture inconsistencies between model predictions and measurements. These residuals are processed into statistical features and passed to a machine learning (ML) classifier for accurate fault detection and classification. In this series-hybrid structure, using SA–EKF residuals as classifier inputs significantly improves diagnostic performance compared to ML-only features, and among the tested classifiers, Residual-based RF achieves the highest accuracy. The method achieves 98.73% accuracy in distinguishing fault types, demonstrating high sensitivity across all faults and robustness to varying noise levels. Overall, the proposed hybrid methodology enhances fault diagnosis effectiveness and supports the safe operation of LIB systems, contributing to the transition toward clean and sustainable energy solutions
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    Effect of lithium chloride on hemolymph components, hypopharyngeal glands, ovarian development, and oxidative stress in honey bee (Apis mellifera L.) workers under controlled conditions
    (Taylor& Francis, 2026) Ghaffar, Intissar; Cherrered, Nawel; Khedidji, Hassiba; Chahbar, Nora; Cresta, Eleonora; Lazzari, Filippo
    One hundred and fifty newly emerged worker bees were transferred into Pain-type cages. The experiment included five replicates per batch: five cages for the control, five for bees treated with 10 mM lithium chloride (LiCl), and five for bees treated with 25 mM LiCl. Pollen paste and syrup consumption were measured at 7 and 14 d. Worker bees were sampled at 0, 7, and 14 d for hemolymph extraction (to measure protein, lipid, and sugar content) and for dissection of hypopharyngeal glands (HPGs) and ovaries. Oxidative stress marker levels were also quantified. The results revealed that LiCl treatment did not significantly affect food consumption (pollen paste and syrup). Protein, sugar, and lipid levels in the hemolymph increased with age (p < 0.001) without any effect from LiCl. HPGs development was significantly reduced by 25 mM LiCl at 7 d (p = 0.003) and by both concentrations at 14 d (p < 0.001). Ovarian development was significantly inhibited by 25 mM LiCl at 7 d (p < 0.001) and 14 d (p = 0.016), whereas 10 mM had no significant effect. Malondialdehyde (MDA) levels and antioxidant capacity were not affected by LiCl but varied with age. These results suggest that a high dose of LiCl (25 mM) disrupts HPG and ovarian development in honey bees without inducing measurable oxidative stress.
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    Photocatalytic degradation of recalcitrant dyes using green synthesized Sr2Fe2O5 nanoparticles: feedforward neural network-based optimization of operating parameters
    (Elsevier, 2026) Ihadadene, Rachida; Nasrallah, Noureddine; Abdellaoui, Karima; Kebir, Mohammed; Bourou, Anis; Hadjadj-Aoul, Fatima Zohra
    This study reports the green synthesis of Sr2Fe2O5 nanoparticles (NPs) using Prunus domestica residue extract as a reducing and stabilizing agent. The synthesized NPs were evaluated as photocatalysts for the degradation of the recalcitrant dye thionine (Th) under natural sunlight irradiation. Structural and morphological analyses confirmed the formation of the brownmillerite phase with spherical nanoparticles of approximately 30.13 nm. The band gap energy (2.38 eV) indicates effective visible-light activation. To enhance the understanding and control of the process, a feedforward neural network was developed to model and optimize the key operating parameters. Under the optimized conditions, a degradation efficiency of 93.37% was achieved within 60 min at a catalyst dose of 0.25 g/L. In addition, a significant reduction in chemical oxygen demand (90.36%) was observed, indicating advanced oxidation of the dye. The treated solution exhibited reduced phytotoxicity, as confirmed by germination tests. These findings highlight the potential of Sr2Fe2O5 NPs as sustainable photocatalysts for wastewater treatment.
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    Heat transfer enhancement in confined slot jets using water-based Cu core–shell and double-shell nanofluids under forced convection conditions
    (Elsevier, 2026) Benmouhoub, Dahbia; Iachachene, Farida; Dalkilic, Ahmet Selim
    eat transfer from confined slot jets is important in several thermal engineering applications, including electronics cooling and turbine blade temperature control. This study presents a numerical investigation of a confined slot jet impinging on a heated wall under forced convection using core–shell nanofluids. The objective is to evaluate the influence of nanoparticle architecture on heat transfer performance. Several configurations are considered, including Cu@Ag, Cu@Au, Cu@Au@Ag, and Cu@Ag@Au. The flow and heat transfer are modeled by solving the Reynolds-Averaged Navier–Stokes equations with the Reynolds Stress Model (RSM) and enhanced wall treatment for Reynolds numbers between 10,000 and 25,000 and nanoparticle volume fractions up to 5%. The numerical approach is validated against data available in the literature. The performance of various core–shell nanofluids was evaluated in terms of heat transfer enhancement efficiency relative to the conventional Cu-water nanofluid. Among them, Cu@Au nanofluids demonstrated the highest improvement, ranging from 32.87% to 43.06%, ranking first. The results also indicate that heat transfer enhancement shows only a weak dependence on Reynolds numbers. These findings suggest that significant heat transfer enhancement is possible with low nanoparticle concentrations, providing practical advantages by minimizing stability and agglomeration issues.
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    Enhancement of the oxidative stability of soybean/sunflower oils and margarine enriched with tomato peel powder
    (Akademiai Kiado ZRt., 2026) Zidani S.; Hennia A.; Djeziri M.; Alileche K.
    This study evaluated the direct use of tomato peel powder to enrich margarine, sunflower oil, soybean oil, and a 1:1 (w/w) sunflower–soybean oil mixture. Dried tomato peels were ground and physicochemically characterised, showing low moisture content (3.11 ± 0.04%), acidic pH (4.10 ± 0.03), and high levels of carotenoids, including lycopene (94.16 ± 1.50 mg/100 g) and β-carotene (19.50 ± 0.75 mg/100 g). Antioxidant activity, determined using the 1,1-diphenyl-2-picrylhydrazyl assay, showed a half maximal effective concentration of 54.46 ± 1.81 mg antioxidant per gram of radical, compared to 120.15 ± 3.18 mg antioxidant per gram for vitamin E, and 67.05 ± 1.92 mg antioxidant per gram for butylated hydroxytoluene. Margarine and oil samples containing 0.25–3.0% tomato peel powder were prepared, and oxidative stability was evaluated over 45 days at 35 °C using peroxide value, conjugated dienes, malondialdehyde content, and induction time. Tomato peel powder significantly reduced lipid oxidation and increased induction times. Oxidative stability improved in margarine (14.81 ± 0.40 h vs. 13.12 ± 0.20 h) and soybean oil (17.67 ± 0.20 h vs. 13.12 ± 0.20 h), extending shelf life. These findings highlight tomato peel powder as an effective natural stabiliser for lipid-based products without solvent extraction
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    Behavioral impact of adolescent social isolation stress: A multidimensional assessment in male NMRI mice
    (Springer, 2026) Belblidia, Hassina; Aroune, Djamila
    Rearing in social isolation (SI) during adolescence compromises brain development and behavior. Most studies have used post-weaning SI that encompasses the entire adolescence period to investigate the consequences of adverse early-life experiences. However, adolescence comprises heterogeneous developmental phases, characterized by differences in the timing of maturation of brain regions and the endocrine system, during which exposure to adverse environments may exert distinct effects on behavioral outcomes. Here, we assessed the immediate effects on a broad range of emotional and cognitive behaviors of a 3-week SI period during mid to late adolescence in male NMRI mice. We employed z-score standardization across behavioral domains, followed by principal component analysis (PCA), to enhance the accuracy of the behavioral phenotyping and to identify domain-specific behavioral vulnerabilities to stress. Our findings indicate that mid to late SI increased locomotor activity and induced anxiety- and depressive-like behaviors, without impairing the cognitive domain. PCA further revealed a significant separation between socially isolated and group-housed animals, with hyperactivity and depressive-like behavior emerging as the main contributors to this differentiation. These results demonstrate that even less extreme forms of SI, when applied from mid to late adolescence, can substantially alter emotional responses. This study highlights the vulnerability of this developmental window and supports the use of the NMRI mouse strain as a relevant model for investigating variability in stress-related behavioral responses