Faculté des Sciences et de la Technologie

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Etude des défauts ponctuels dans les demi-Heusler à 18 électrons : méthodes de premiers principes
(2026) HADBI Mohammed; DEMMOUCHE Kamel
This thesis investigates 18-electron half-Heusler compounds TiIrSb, ZrIrSb, TaIrGe, and TaIrSn in terms of their structural, electronic, optical, and thermoelectric properties using first-principles calculations. Particular emphasis is placed on the TiIrSb compound, where the effect of substituting titanium (Ti) atoms with zirconium (Zr) atoms in the 2 × 2 × 1 supercell on its physical properties, including dynamical stability, is examined, in addition to studying the influence of point defects of vacancy and antisite types on its structural, electronic, and optical stability. The VASP package, based on DFT, is employed with the PBE-GGA exchange– correlation functional, together with the Meta-GGA-SCAN functional to improve the accuracy of the predictions, while the calculations are performed within the supercell approach to assess the thermodynamic stability through formation energies and the dynamical stability through phonon calculations. Moreover, the hybrid functional HSE06 is used to investigate the electronic properties of the four compounds TiIrSb, ZrIrSb, TaIrGe, and TaIrSn, aiming at a more accurate description of the band gap and electronic structure.
Effets des paramètres atmosphériques sur la décharge couronne dans différentes configurations des précipitateurs électrostatiques
(2026) HEBBAR Nihed; AISSOU Massinissa
The aim of this research project is to improve the performance of electrostatic precipitators (ESPs), devices widely used in industrial processes to treat particulate emissions. The main objective of this thesis is to study the influence of atmospheric conditions - mainly humidity and temperature - on the particle collection efficiency in different geometric configurations of electrostatic precipitators. Experiments have been carried out in the laboratory on model precipitators of the multipoint-two planes, and blade-planes types. Three types of particles of different sizes and densities were injected to evaluate the response of the devices under varying conditions. Analysis of the results revealed differentiated behaviours depending on the precipitator configuration and the atmospheric parameters applied. The results show that relative humidity has a strong influence on corona discharge formation and, consequently, on particle capture rates at. Temperature, on the other hand, affects air density and ion mobility, modifying the trajectories of charged particles, which has a direct impact on collection efficiency. Certain geometrical configurations proved more robust than others in the face of these environmental variations did.
Etude et conception d’un système de distillation membranaire intégré pour la purification de l’eau et la production d’énergie.
(2026) BOUSMAHA Mouad; NEHARI Driss
This study investigates the modeling, simulation, and performance analysis of a solar-assisted direct contact membrane distillation (DCMD) system for freshwater production in arid and semi-arid regions. A dynamic co-simulation approach, combining TRNSYS for solar thermal modeling and MATLAB for detailed DCMD module modeling, was developed and validated under real climate conditions in Ain Témouchent, Algeria. The system integrates flat-plate solar collectors (2 to 6 m2), a 300- liter hot water storage tank, an auxiliary heater, and 0.5 m2 of PVDF flat-sheet membrane modules. The DCMD module, modeled using heat and mass transfer equations, allows for co-current and counter-current operation. The simulation included two configurations: a basic system without heat recovery and an enhanced system with an economizer to recover residual heat from the membrane outlet. The simulation results demonstrate the high performance and potential of the proposed solar integrated DCMD system for freshwater production. Membrane water production reached up to 13.57 kg/m2·h, with an average daily yield of 54.28 liters during the standard 8-hour operation window. The solar fraction peaked at 71%, and the solar collector efficiency reached a maximum of 63% in July, indicating strong alignment with seasonal solar resource availability. The annual performance simulations indicated the best balance between energy efficiency, water productivity. The economizer successfully recovered thermal energy from the membrane outlet stream, preheating the incoming feed and significantly reducing thermal losses. This improved the overall thermal efficiency by reusing the membrane outlet heat, reducing system losses, increasing effective temperature at the feed inlet. and a daily water production increased from 54.28 liters/day to approximately 100 liters/day, despite a reduction in operating time from 8 hours to just 5 hours a clear indication of a more efficient desalination process. The TRNSYS-MATLAB co-simulation framework proved to be a powerful and flexible tool for modeling, design, and performance optimization of solar-thermal desalination systems.
Etude Plasmonique et Photonique pour la Conception et l’Optimisation des capteurs en CPs a base de Matériaux photoniques multifonctionnels
(2026) OUARDI Mohamed Esseddik; TAYEBOUN Fatima
Over the last decades, a big number of scientific publications (articles, books, presentations, etc.) has been produced in photonic physics, most especially in the field of sensors, for the optimization of their accuracy and their miniaturization and make them cost-efficient. The aim of this work is to design SPR biosensors under the Kretschmann-Raether configuration. With simple and achievable structures. We have studied the effect of many materials such as black phosphorus, silicon dioxide, zinc monoxide, transition metal dichalcogenides (TMDC), rhodium, gallium arsenide and magnesium fluoride on the SPR-based sensor’s response. In comparison with other works in the same field, simulations show that the proposed biosensors deliver excellent performances. With sensitivities going from 238 to 499 deg/RIU for various applications in the medical, environment and agri-food fields. Results were provided using the transfer matrix method (TMM).
Etude sur les paliers de Turbocompresseur cavitants à haute vitesse avec prise en compte de l’effet élastohydrodynamique en régime instationnaire
(2026) SAID Abdelmadjid; BOUNIF Abdelhamid
This study focuses on the analysis of the dynamic behavior of crankshaft and turbocharger bearings, critical components in engines and rotating machines, whose performance directly impacts the efficiency, reliability and overall system performance. The study explores in detail the effects of cavitation and surface deformations on these bearings, particularly those of the connecting rod (big end and small end) and the turbocharger. For turbocharger bearings, a dynamic computational model has been developed to determine key parameters such as the pressure field, minimum lubricant film thickness, leakage flow and friction torques. The minimum lubricant film thickness is a key indicator to assess the risk of friction and wear. The study also highlights the challenges of high-speed elastohydrodynamic lubrication, taking into account the interaction between the Reynolds equation and bearing surface deformations. These calculations are performed using the Booker mobility method and the Winkler deformation model, in an iterative numerical approach. Concerning connecting rod bearings, the analysis focuses on the rupture and reformulation of the fluid film in the contact zone, particularly in the inactive cavitation zone. The operating parameters are studied for finite length bearings and compared to those obtained with the simplified assumption of short bearings. This comparison shows that the assumption of short bearings significantly reduces the calculation time while providing results similar to those of more complex models. In summary, this thesis proposes an advanced numerical approach to simulate the hydrodynamic and elastohydrodynamic lubrication conditions in connecting rod and turbocharger bearings, using a calculation program implemented in FORTRAN. The results obtained contribute to a better understanding of the physical phenomena involved and to the optimization of the performances of these critical components.
Étude numérique et expérimentale de la résistance thermique de contact aux interfaces LAITON-SAPHIR
(2025) BOUHADJELA Fatiha; Bensaad Borassia
The thesis topic relied to the theme of mechanics and thermal interaction of solid-solid contact. It focuses on the analysis of the mechanical phenomena involved in metal interfaces and their effect on heat transfers through the very thin heterogeneous layer known as the transition layer which extends on both sides of the theoretical plane of contact. For a long time, this theme raised an interest and there are numerous articles dedicated to the characterization of interfaces as well as to the modeling of thermal resistance of contact. It, should also be noted that in all industrial sectors, including the automobile, aeronautics and the material shaping industry, the knowledge requirements and the mastery of mechanical and thermal phenomena at metal interactions are becoming increasingly important. In practice, the analysis of heat transfer phenomena at this level uses the concept of thermal contact resistance (TCR). This resistance is related to the actual contact pressure and geometric parameters characterizing the surfaces of the solids at the interface. Thus the mechanical deformation of the surfaces involved in contact and the evolution of their mechanical properties during loading have a decisive effect on the heat transfers in this area. This work completes the study of B. Bensaad’s thesis on sapphire-brass thermal contact resistance with an experimental approach. The objective of the study is to develop a mixed approach (numerical/semi- empirical) which consists of using semi-empirical model sempirical using as input variables quantities determined by numerical simulations by finite elements which allow the TCR to be calculated taking into account the phenomena involved in the contact: roughness of the contact surfaces, pressure, temperatures, etc. The numerical model will be validated using the results obtained by B. Bensaad study.
Nouvelles stratégies de synthèse des composés polycycliques
(2026) Benzenine Djamila; Kibou Zahira
This thesis presents the development of eco-friendly synthetic methods for producing imidazo-heterocycles and 2-pyridones, utilizing techniques such as solvent-free synthesis, catalysis, microwave irradiation, and ultrasound. Following the successful synthesis of these compounds, their practical applications were investigated. The inhibitory effectiveness of selected imidazo- heterocyclic derivatives on mild steel corrosion was evaluated, highlighting their potential as corrosion inhibitors. Additionally, the biological activity of the synthesized imidazo[1,2-a]pyridines/pyrimidines was tested, revealing promising pharmacological properties. Molecular docking studies were performed to model the interactions of potent compounds with specific biological targets, providing insights into their therapeutic potential. This research advances the synthesis and application of heterocycles in industrial and biomedical contexts.
Etude phytochimique, activité anti-oxydante et antibacterienne des huiles essentielles de deux plantes médicinales : in vitro et in silico
(2025) SAIDI, Ainayat ellah; BOUZIDI, Nebia
Nepeta nepetella subsp. Amethystina (Poir.) Briq and Satureja candidissima Munby Brik are medicinal and aromatic plants belonging to the Lamiaceae family, traditionally used in Algerian medicine. This study aims to analyze the phytochemical composition, evaluate the antioxidant and antibacterial activities, and predict the mechanism of action of the essential oils extracted from the aerial parts of N. nepetella and S. candidissima, collected from the regions of Naâma and Ain Temouchent, respectively. Qualitative analysis using GC-MS of the obtained essential oils revealed chemical variability, with 57 compounds identified in N. nepetella essential oil and 54 in S. candidissima essential oil, representing 90.98% and 91.01% of the total composition, respectively. The major components of N. nepetella essential oil are 4aα,7α,7aβ-Nepetalactone (58.98%), 4aα,7α,7aα-Nepetalactone (10.23%), Spiro(5.6)dodecane (5.45%), and Camphor (4.98%). For S. candidissima, the major components include Pulegone (53.26%), (+)-Menthone (11.02%), Borneol (4.43%), 2-Cyclohexen-1-one, 3-methyl-6-(1-methylethylidene) (2.50%), and 3- Octanol (2.09%). Biologically, DPPH and FRAP tests demonstrated that Nepeta nepetella essential oil exhibits stronger antioxidant activity than Satureja candidissima. However, for total antioxidant capacity (CAT), Satureja candidissima showed greater effectiveness. Additionally, Satureja candidissima exhibited higher antibacterial activity against Escherichia coli, Bacillus cereus, Staphylococcus aureus, and Pseudomonas aeruginosa, whereas Nepeta nepetella was more effective against Bacillus licheniformis and Listeria monocytogenes. In silico molecular docking and ADMET studies were conducted to elucidate the underlying antibacterial mechanism and antioxidant potential. The recorded data indicated that the antibacterial activity of the essential oil compounds could be attributed to the inhibition of enoyl-[acyl-carrier-protein] reductase FabI [NADPH] (PDB ID: 4ALL). The most active compounds were minor components. Docking results also suggested that the essential oil components could exert their antioxidant activity in vitro by inhibiting xanthine oxidase (PDB ID: 3NRZ). Therefore, N. nepetella and S. candidissima could serve as novel natural sources of antioxidants and antiseptics, with potential applications in the food and pharmaceutical industries as alternatives to synthetic additives.
Conception, optimisation et réalisation de nouvelles antennes micro ruban intelligentes miniatures reconfigurables pour les réseaux mobiles
(2025) MOHAMMED BELHADJ, KHOULOUD; Ferouani, Souheyla
This thesis focuses on the design, optimization, and development of intelligent, miniature, and reconfigurable microstrip antennas tailored for modern wireless technologies such as 5G, Wi-Fi 6, and the Internet of Things (IoT). Two types of frequency-reconfigurable antennas were developed: a rectangular printed antenna, providing reliable coverage at 3.53 GHz and 5.0 GHz for 5G and Wi-Fi 6 applications, and a pentagonal patch antenna, covering a wide frequency range (2.438 GHz to 7.805 GHz) suitable for various applications, including Wi-Fi, LTE, radar, satellite, and IoT. The study also focused on Yagi antennas with reconfigurable radiation patterns using PIN diodes. The single-element Yagi antenna generates a radiation pattern in the ON mode and is inactive in the OFF mode. The two-element Yagi antenna, with three distinct modes (ON-ON, ON-OFF, OFF-ON), enables effective beam reconfiguration for WiMAX, and 5G technologies. The results demonstrate that these reconfigurable antennas optimize spectrum utilization while improving signal coverage and quality. They provide efficient and flexible solutions for modern telecommunications, contributing to more effective networks adapted to the evolving needs of a connected environment.
ANALYSE NUMERIQUE MULTI- ECHELLE DE LA DEFORMATION D'UN EMPILEMENT DE COUCHE MINCE DESTINE A DES APPLICATION MICRO ELECTRONIQUE
(2025) El Fatmi, Imad; BELHENINI, Soufyane
The manufacturing of microelectronic components is moving towards increased miniaturization and optimized performance to meet economic and strategic challenges. To achieve these objectives, manufacturers use thin films of various materials, typically deposited on silicon substrates. However, these manufacturing methods, carried out at different temperatures, cause warping due to differences in the coefficients of thermal expansion between the thin layers making up the stack. This warping can disrupt the manufacturing process, leading to issues such as defects during photolithography, difficulties in automated equipment detecting wafers, or even risks of breakage during handling. To avoid these complications, it is essential to predict the level and distribution of deformations within the stack. Numerical simulation is commonly used to study these problems, offering significant advantages for rapid industrial application. The work conducted within the framework of this thesis is based on three main points: 1. Numerically determine the warping of the Si/USG/Pt stack while respecting the steps of the manufacturing process. 2. Introduce and validate simplifications to facilitate numerical modeling, notably replacing the actual thermal loading with an equivalent loading and integrating homogenization techniques to obtain an equivalent model. 3. Numerically study the effect of trimming on reducing the warping of a thin-film stack. The numerical approaches undertaken in this work were validated by comparisons with experimental results. The results thus obtained highlight the importance of taking warping into account in layer stacks. The contribution to simplifying the numerical approach can be used by industry professionals to reduce the time allocated to developing new microelectronic solutions.
Study the effect of common contaminants on rat pancreatic cell physiology
(2025) BENCHIKH, Imen; ZIANI, Kaddour
The neonicotinoid insecticide acetamiprid has been linked to toxicity in various organs and organisms. However, its effects on the exocrine pancreas remain largely unexplored. This study aimed to investigate the toxic effects of acetamiprid on the exocrine pancreas through in-vivo and in-vitro investigations. We also explored the potential preventive effects of carnosine. In the in-vivo study, male Wistar rats were administered acetamiprid orally at two doses (21.7 and 43.4 mg/kg/day, respectively) with or without carnosine supplementation (200mg/kg/day) for 30 days. The body and pancreatic weight were measured, malonaldehyde, glucose, lipase, amylase levels, and histopathological examination were evaluated. In the in-vitro study, AR42J pancreatic cells were exposed to acetamiprid with or without carnosine, and the cell viability, MAPK signaling pathway, intracellular calcium levels, and trypsin secretion were investigated. Sub-acute acetamiprid exposure led to significant adverse effects, including decreased body weight and pancreatic somatic index, increased blood glucose, altered pancreatic enzyme levels (decreased amylase and increased lipase levels), and elevated malondialdehyde levels. Histological examination revealed damage to pancreatic tissue. While carnosine supplementation partially mitigated these adverse effects. Acetamiprid exposure altered AR42J pancreatic cell viability in a dose-dependent manner, while co-treatment with carnosine significantly improved cell survival, and activated the MAPK signaling pathway, which was attenuated by carnosine. While acetamiprid increased intracellular calcium levels, it did not significantly affect trypsin secretion. This study shows that acetamiprid harms the exocrine pancreas. However, carnosine supplementation may offer protection against these harmful effects.
Etude et conception des nano-antennes optiques micro-rubans
(2024) MOULFI, BOUCHRA
Etude comparative des propriétés structurales, électroniques, optiques et thermoélectriques des alliages à base de bismuth et à base de lanthanides
(2024) ADDOU, Oussama; TOUIA, Amina
The present work is a study of physical properties (structural, electronic, optical, and thermoelectric...etc.), alloys based on bismuth, and lanthanides. This will allow us to define the problem of phase stability as well as the problem of the role of electrons in this stability using the method of augmented and linearized plane waves at total potential (FP-LAPW) implemented in the Wien2k code. Materials based on bismuth and lanthanides have been intensively studied because of their numerous technological applications, especially in the fields of spintronics, optoelectronics and thermoelectric (renewable energy sources).
Contribution à l’étude des transferts dans des mortiers à base de kaolinite: de la perméabilité à la microstructure
(2024) BENAMAR, Souheyla; Houmadi, Youcéf
From an ecological and economic point of view, the present research aims to contribute to the valorization of calcined clays as supplementary cementitious materials (SCMs) in the composition of cementitious mortars. So, the objective of this study is to evaluate the influence of three SCMs which are: metakaolin (MK), calcined sediments (VC) and brick powder (PB) (added by substitution of cement with different dosages, ranging from 10 to 30%) on the physic-mechanical and durability properties of the tested mortars. In addition to a mechanical characterization of the mortars studied, a major interest is given to the evaluation of some transfer parameters in these modified mortars, such as open porosity, capillary absorption, water permeability, water vapor transmission permeability and carbonation (measured in accelerated and natural conditions). The impact of the carbonation of the material on the transfer properties was also investigated in this experimental study. The results obtained showed that the substitution of cement by 25% MK, 20% VC and 15% PB allowed obtaining the best mechanical strengths of the mortars. The MK-based mortar always showed the best performances, both in terms of physic-mechanics and durability, compared to the other mortars (based on VC and PB). Compared with the control mortar, the MK, VC and PB-based mortars ensured better durability performances. These three SCMs used decreased the porosity and permeability of the cementitious material, mainly because of their fineness and because of the Portlandite consumption by the pozzolanic reactions produced by the incorporation of these SCMs in the mortar. In contrast, this behavior can be contradictory in carbonated mortars: transfer properties in the mortar, such as porosity, can be higher in mortars based on MK, VC, or PB than in the reference mortar (without SCM). Consequently, the resistance to carbonation is also influenced in the opposite way. A phenomenon directly attributable to the microcracking effect influenced by shrinkage due to carbonation. The effect of carbonation on the transfer properties therefore depends on the initial mineralogical composition of the material. In order to simulate the carbonation depth of the different mortars studied, a model based on Artificial Neural Networks (ANN) was developed to predict the depth of carbonation of materials based on MK, VC and PB. The prediction model was developed using the experimental results of carbonation measured in accelerated and natural conditions. The model's development took into account parameters related to the characteristics of the mixture (cement content, SCMs content, mortar age) and parameters related to environmental conditions (CO2 concentration, relative humidity, temperature and exposure time to CO2). The learning, validation and testing performance of the developed ANN model showed very good correlations, exceeding 90%, between the experimental values and the values predicted by the model.
Synthèse et activité biologique de nano-composite à base des nanoparticules d’argent
(2024) TAIEB AMARA, Yousra; BOUSSLEM, Smain
This contribution reports a simple and environmentally friendly method for synthesizing silver nanoparticles (AgNPs) using aqueous leaf extract of Mentha aquatica. The impacts of various operational parameters such as leaf extract dosage, solution pH, temperature, and contact time on the formation of AgNPs were examined in detail. Data revealed that 5% v/v Mentha aquatica leaf extract, a pH of 9.0, a temperature of 18°C, and an incubation time of 60 minutes yielded optimal nanoparticle synthesis. The resulting AgNPs were analyzed using UV-Vis spectroscopy, FT-IR, and X-ray diffraction (XRD). TEM images showed that the AgNPs were predominantly spherical, with an average particle size of 25 nm. Furthermore, the DPPH (2,2-diphenyl-1-picrylhydrazyl) assay was used to study the antimicrobial properties against Gram-positive and Gram-negative pathogens and the catalytic activity of the synthesized silver nanoparticles. The results demonstrated that the nanoparticles exhibited promising antioxidant and antibacterial activities. Additionally, significant catalytic activity in the degradation of methylene blue (MB) was observed, with a maximum degradation capacity of up to 98% at a catalyst dose of 2 mg. Therefore, a simple and easy-to-implement green approach for the synthesis of silver nanoparticles with high degradation capacity is presented. Hexagonal mesoporous silica MCM-41 is one of the commonly used hosts for incorporating silver nanoparticles, providing pore channels suitable for confining ultrafine metal nanostructures within its channels. Ag nanoparticles were confined inside the pore channels of MCM-41 by an in situ biological reduction method. XRD and FTIR were used to characterize the MCM41-AgNPs composites. These MCM41-AgNPs catalysts showed excellent catalytic activity for dye removal compared to its absence in the reaction medium, with the plasmon band position between 650 and 675 nm.
Préparation et caractérisation des nanomatériaux, application en synthèse organique
(2024) YADI, Hind; Bailiche, zohra
In recent years, the remarkable catalytic properties of gold, a precious metal, have attracted considerable interest. The dispersion of the gold, as well as the structure and interaction between the gold nanoparticles and the supports, and the type of support used, are well-established factors that influence the catalytic and adsorption properties. One of the main challenges facing supported gold catalysts is the agglomeration of the gold particles, which leads to deactivation of the catalyst. The porosity of the support material plays a crucial role in controlling the agglomeration of the metal particles. Mesoporous materials, in particular SBA-15 mesoporous silicas, are receiving particular attention due to their high specific surface area, large pore size, thick silica walls for thermal and hydrothermal stability and high surface hydroxyl density, as well as their exceptional performance as highly efficient catalysts. However, the use of mesoporous silicas as acid supports poses a problem for gold deposition. The negatively charged surface of the silica hinders the adsorption of gold precursor anions. It therefore becomes imperative to modify the surface properties of mesoporous silicas by incorporating functional groups on the channel walls.Generally, functional organic groups containing polar moieties are introduced into mesoporous silicas to stabilise nanoparticles and inhibit their aggregation. In addition, the creation of solid heterogeneous catalysts containing organic functionalities is considered to be a convincing solution. In this context, the first part of this thesis was devoted to the design of a heterogeneous catalyst based on gold nanoparticles dispersed on amine-modified SBA-15 mesoporous silica (Au/SBA-15-NH2).The catalyst was characterised by various techniques: powder XRD, N2 adsorption/desorption, FT-IR spectroscopy. The results show that the SBA- 15 silica has a stable, ordered structure even after organo-functionalisation with aminopropylsilane, and that the gold nanoparticles are located in the pores of the SBA-15 with average sizes of 1-8 nm. In the second part, the reactivity of the catalyst was examined in a four-component coupling process for the synthesis of β-acetamido ketones, which are versatile mediators in that their skeletons exist in a number of pharmaceutical and biological substances. Thus, the chosen methodology offers many advantages, including high yields, a simple procedure and fast reaction times. The approach of the third part is to evaluate the effectiveness of the mesoporous silica support SBA-15 functionalized with organic binders containing amines, to inhibit copper corrosion in various acidic environments. The results show that the support is an excellent inhibitor for protecting copper against corrosion, particularly in a 0.5M sulphuric acid environment. Finally, the biological activity of the materials synthesised was studied.
Etude et conception des composants optiques à base de fibres à cristaux photoniques.
(2024) HARRAT, ASSIA AHLEM; DEBBAL, Mohammed
This thesis explores the applications of photonic crystal fibers (PCFs) in optical telecommunications. The focus is on optimizing the chromatic dispersion of PCFs to enhance their performance in data transmission. Extensive research is conducted on optical components based on PCFs, with significant advancements in the design of multiplexers/demultiplexers and power splitters. The Beam Propagation Method (BPM) is employed to model the structures, confirming the effectiveness of the proposed solutions. The results are supported by detailed simulations and rigorous analyses, thus strengthening the position of PCFs as a promising solution for modern optical telecommunication networks. The contributions of the thesis are recognized through publications in reputable journals and presentations at national and international conferences. Looking ahead, ongoing optimization of existing structures and the design of new, more complex components offer exciting opportunities to expand the use of PCFs in advanced optical systems.
Synthèse des molécules à activités biologique et thérapeutique par des catalyseurs nanostructurés
(2024) DRICI, Mohammed el amine; Berrichi, Amina
Propargylamines and pyrroles are very interesting intermediates molecules; they exhibit biological and therapeutic activity. They are well known as neurodegenerative drugs. These molecules exhibit different biological activities such as anti-inflammatory, anti-HIV and others. The synthesis method of these molecules involves the use of metallic and non-metallic catalysts. The synthesis methods described in the bibliography have shown that metal phosphate catalysts have not been used in the synthesis of propargylamines and pyrroles. In our thesis, we prepared nanostructured FePO4 and FeCuP2 catalysts via one-pot hydrothermal method. The prepared catalysts were characterized by different methods such as UV-Vis, IR, SEM, EDX, Raman, and TEM. The characterization results confirmed the nanoscale structure of the prepared catalysts. The catalysts FePO4 and FeCuP2 were used in the synthesis of propargylamines by the A3 coupling of an aldehyde, an alkyne and an amine, and by the AHA coupling of an amine, an alkyne and diiodomethane. Both catalysts exhibit good activity and stability with propargylamine yields ranging between 50-100%. For the synthesis of pyrroles, the FeCuP2 catalyst showed good activity in the four components reaction of aldehyde, amine, nitroalkane and ethyl acetoacetate. Thus, a reaction mechanism was proposed in the presence of these nanostructures. The synthesized propargylamines and pyrroles have good biological activity, they demonstarted an anti inflammatory and anti-oxidants activity. Propargylamines have therapeutic activity against Alzheimer's disease; this study is carried out theoretically by molecular docking.
Conception de Capteur à Base des Fibres Optiques.
(2024) MIRED, ILHEM; DEBBAL, Mohammed
This research explores the potential of photonic crystal fibers (PCF) for the design of high- sensitivity sensors, addressing the growing demand for effective detection solutions across various fields, such as high flexibility in guiding light and strong interaction between the fiber core and the external environment. The thesis focuses on the numerical modeling of PCFs, allowing for the identification of key geometric parameters that influence their optical properties and, consequently, the sensitivity of the sensors. The numerical technique used to simulate light propagation is the Beam Propagation Method (BPM). This method is useful for modeling the evolution of electromagnetic fields in non- homogeneous optical guiding devices, which is essential for designing sensitive and efficient optical sensors. The contributions of this thesis open up new promising perspectives for the development of PCF-based sensors, offering innovative solutions for various applications, particularly in health, environmental, and industrial fields. The study proposes future research directions, including the integration of nanomaterials into PCF structures, the development of multiparameter sensors, and the optimization of fabrication techniques. The results of the thesis highlight the potential of PCFs for creating high-sensitivity, optimally performing sensors, thus contributing to the advancement of detection and monitoring technologies.
Contribution à l’étude du comportement thermo-électromécanique des connecteurs de puissance
(2024) HADDA, Kada; BELOUFA, Mohammed El Amine
Electrical connectors play a crucial role in modern electrical systems, ensuring the connection and transmission of powerful electrical currents between various components. In satellites, they link solar panels to batteries and other subsystems. In launchers, they connect the power supply stages. In airplanes, drones and hybrid or electric automobiles, they link batteries and electric motors. Résumé 170 The increasing power in modern electrical systemes poses new challenges to connectors. High currents generate significant heat due to the Joule effect, which can damage contact surfaces by softening or melting them. Additionally, the separation of connectors, whether intentional or unintentional, can create intense electrical arcs, accelerating erosion, corrosion, and material transfer between contact surfaces, irreversibly affecting connector performance. This research aims to experimentally analyze the impact of electrical arcs on the performance of electrical connectors. The main objective is to identify the most erosion and degradation-resistant materials and contact geometries caused by electrical arcs. An experimental test bench has been developed to simulate contact opening under controlled conditions, faithfully reproducing real-world usage conditions. This bench allows for the application of precise electrical currents and the measurement of physical properties of generated arcs, such as arc’s duration and length, arc’s energy and power.... SEM analysis and MHD numerical calculation using Fluent software enabled us to analyze and understand the arc phenomenon and compare the numerical results with the experimental results. This research makes a significant contribution to understanding the degradation mechanisms of electrical connectors under the influence of electrical arcs. The results obtained will help optimize the design and material selection of connectors to improve their reliability and durability in the demanding environments.

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