Publications Internationales
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Item Study of the Insecticidal Potential of Diatomaceous Earth from Sig (Algeria) on the Dermestes haemorrhoidalis - A Pest of Stored Food Product(2021) Djadi, Amina; Bouzid, Mohammed; Bezzazi, B.The insecticidal activity of the Diatomaceous Earth (DE) of Sig was assessed against the Dermestes haemorrhoidalis, which is the main pest affecting wheat stored in Blida, a central region of Algeria and one of the four cereal regions managed by the Algerian Inter-branch Cereals Office (AICO). The formulation was tested at two different doses: 500 and 1000 ppm against adults of the species. The bioassays were carried out in 1-litre glass jars containing soft wheat with an average moisture content of 60% mixed with diatomaceous earth and maintained at 27°C and 70% of humidity. The effectiveness of the treatment was assessed by recording adult mortality after 2, 7 and 14 days. Sig’s diatomite showed significant insecticidal activity against Dermestes haemorrhoidalis after only two days of treatment with both doses 500 and 1000 ppm. After 14 days, average mortality was more than 95% even at 500 ppm. Furthermore, electron microscopy of the diatomite particle from Sig (Algeria) reveals the architecture of the frustule. It shows a porous and brittle siliceous shell made largely of diatomite “skeletons”. This research work allowed getting insights into the mechanism of action of diatomite on the Dermestes haemorrhoidalis. On the other hand, the identification of diatomite of Sig was performed by X-ray diffraction and infrared.Item Study and Physicochemical Characterization of the Diesel Particles Inducing Bronchopulmonary Obstructions and Inflammation(Technoscience Publications, 2021) Bouzid, Mohammed; Djadi, A.; Bezzazi, B.Micro-Visiography reveals that diesel soot particles are soluble in the physiological pulmonary liquid. It also shows that these substances stick to bronchial capillary walls. Electronic microscopy reveals structures of non-homogeneous morphology with spherical, fibrous and platelet-like structures. Analysis of the surfaces of the aggregates by Energy-dispersive X-ray microanalysis (EDX) shows the composition of chemical charges. Besides, X-ray diffraction and thermogravimetric study show the existence of two phases: Organic and crystalline, with a rubber elastomer aspect. Infrared and UV-Visible spectroscopic analysis confirmed the existence of reactive chemical groupsItem Elaboration et caractérisation mécanique d’un matériau composite hybride(2006) Hachemane, B.; Mir, A.; Bezzazi, B.Item Quasi-static mechanical characterization and fatigue of a composite laminates(2014) Belkacemi, C.; Bezzazi, B.This present work focuses on the quasi- static mechanical characterization and or fatigue of a composite materials (laminate) jute/polyester manufactured under vacuum and with stacking sequences of 0/ 90. The obtained results of tensile tests on the laminate, showed a similar behavior on two levels: a linear portion up to 20 MPa and a nonlinear portion to rupture at 47 MPa σ max , followed by elongation of 2.08 % with a break elongation up to 2.50 %. Also, it was noted that increasing the temperature of the samples (5-6 ° C ) when the fatigue test remains in ISO 13003 , which requires a temperature increase of less than 10 ° C. the results of fatigue test showed also that with a loading of 50% of the maximum load reached more than one million cycle, the more load is increasing the cycle numbers of decreasesItem Experimental study of sandwich multilayer reinforced by glass fibre and agglomerated cork(2014) Hami, Brahim; Irekti, Amar; Aribi, C.; Bezzazi, B.; Mir, A.This paper presents an experimental study which is determined the mechanical properties of a composite material sandwich multilayer developed in the laboratory of mechanics of materials and composites, Materials Research Unit, process and en¬vironment. This type of sandwich is composed of four layers laminated based on an epoxy resin reinforced by woven glass fibres and mast between which three plates of agglomerated cork with stacked alternately laminated layers. Specimens for bending tests three and four points were prepared from the multilayer sandwich panels. A first series of static three-point bending tests shows a clear difference in the fracture behaviour for materials, laminate and cork. These materials have undergone a large plastic deformation without rupture achieve full sandwich, with the onset of delamination between layers laminated material and cork. In order to determine the bending stiffness modules D, the shear modulus and flexural N and the shear modulus of the soul Ga, we conducted a second test campaign four points bending. As a result, we can develop a variety of white cork produced in Algeria in order to use it in the construction and automotive industriesItem Study of the green composite Jute/Epoxy(2014) Mir, A.; Aribi, C.; Bezzazi, B.Work presented is interested in the characterization of the quasistatic mechanical properties and in fatigue of a composite laminated in jute/epoxy. The natural fibers offer promising prospects thanks to their interesting specific properties, because of their low density, but also with their bio-deterioration. Several scientific studies highlighted the good mechanical resistance of the vegetable fiber composites reinforced, even after several recycling. Because of the environmental standards that become increasingly severe, one attends the emergence of eco-materials at the base of natural fibers such as flax, bamboo, hemp, sisal, jute. The fatigue tests on elementary vegetable fibers show an increase of about 60% of the rigidity of elementary fibers of hemp subjected to cyclic loadings. In this study, the test-tubes manufactured by the method infusion have sequences of stacking of 0/90° and ± 45° for the shearing and tensile tests. The quasistatic tests reveal a variability of the mechanical properties of about 8%. The tensile fatigue tests were carried out for levels of constraints equivalent to half of the ultimate values of the composite. Once the fatigue tests carried out for well-defined values of cycles, a series of static tests of traction type highlights the influence of the number of cycles on the quasi-static mechanical behavior of the laminate jute/epoxyItem Study of mechanical and thermomechanical properties of jute/epoxy composite laminate(2010) Mir, A.; Zitoune, R.; Collombet, F.; Bezzazi, B.This article presents the development and the characterization of composite material (laminate) containing natural jute fiber reinforcement. Thermal characterization of jute fiber reinforcement shows the influence of the temperature on the mechanical behavior of fiber. At 180 C the jute fabric loses 50% of its mechanical characteristics. The laminate obtained by a process known as infusion is polymerized at a temperature lower than that which affects the mechanical properties of dry fabric. The digital image correlation carried out on laminated jute/epoxy (warp and weft direction) under tensile test shows the presence of a considerable gradient of deformation. This gradient is explained by the variability related to the local voluminal change of jute fibers of one place to the other and the nature of the weaving of the jute fiber. The three-point bending tests show a significant dispersion of rupture stress. The thermomechanical tests carried out on samples in the two principal directions, show that the thermal coefficient of expansion in warp direction is 48% larger compared to the weft direction. The thermogravimetric test shows that this laminate absorbs up to 4% water mass after 8 h in a climatic chamber with 70% moisture contentItem Study of mechanical and hygrothermal properties of agglomerated cork(2012) Mir, A.; Bezzazi, B.; Zitoune, R.; Collombet, F.The mode of development of sandwich panels with cork core by the method infusion cannot prevent the resin from penetrating inside cork. This study characterizes white cork agglomerated before and after the development of sandwich panels to see the influence of the resin on the mechanical and hygrothermic characteristics of cork. Two types of cork are considered, they are characterized by their density of 270 kg/m3 (C270) and of 190 kg/m3 (C190). One notes that the modulus of rigidity of C270 cork is 20% larger than that of C190.The presence of resin increases also the module of shearing 47% for C270, 64% for C190. The hygrothermic analysis out of drying oven at 100°C shows a fall of significant mass in the first 7 hours. The analysis thermogravimetry at 220°C, the fall of significant mass is recorded in the first 5 minutesItem Sandwich composites impact and indentation behaviour study(Elsevier, 2013) Hachemane, B.; Zitoune, R.; Bezzazi, B.; Bouvet, C.In order to better exploit the natural cork available in Algeria, an experimental characterisation of a jute/epoxy–cork sandwich material to impact and indentation was undertaken. The aim of this work is to evaluate the impact energy and cork density influence over the sandwich plate damage behaviours by instrumented static and dynamic tests. The results show that the onset damage force, the maximum force and the damage size are influenced by the cork density and the impact energy. The sandwich material, with the heavy agglomerated cork having a density of 310 kg/m3 is characterised by a weaker energy dissipation capacity, by about 3.72% for impact test and 3.29% for indentation one, than the sandwich with lighter cork (160 kg/m3). This difference is an infusion process consequence. The infiltrated resin into the agglomerated cork pores changes the material local rigidity. Also, under impact loading the sandwich laminates dissipate 11% more energy than with the quasi-static indentation testItem Rheological study of composite materials based on thermosetting matrix and fillers mineral(2013) Irekti, Amar; Bezzazi, B.In the development of composites materials, the matrix acts as a binder of different reinforcements can distribute the stress, provide good resistance to chemical structure and the desired shape to the final product. But there are still some drawbacks that arise in the physicochemical and mechanical properties of thermosetting matrices. Our job is to synthesize composite materials with news formulations of thermosetting matrices (Granitex products) by the incorporation of 40% of local mineral fillers. The latter give the matrix properties which it does not have, first, to reduce the cost of composite materials, and secondly, to improve implementation by increasing the viscosity and reducing the withdrawal to its minimum value. Rheological testing of mixtures prepared is made on the cone-plate viscometer, or the sample undergoes a shear in the conical space between the plane and the cone. The geometry of the cone - package ensures constant velocity gradient throughout the volume. The rheograms obtained, represents the evolution of the shear stress as a function of shear rate of resin mixtures containing 35% of mineral filler (pozzolan). The mineral filler increases significantly in rheological parameters, whatever the nature of the mineral filler. Compared to the control without charges, an increase of 60% of the shear stress and that of plastic viscosity were recorded for the epoxy resin. The software Rheowine viscometer, enabled us to model and identified the rheological behavior of these mixed with resin. The results obtained in this modeling, confirmed that the resin mixtures have shear-thinning rheological behavior and their behavior follows the model of the Ostwald of Waele
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