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This work aims to propose an implicit algorithm for solving the magnetoelastic wave propagation in a magnetostrictive actuator. This algorithm is built by combining meshless methods with the Newmark implicit time scheme. The mathematical formulation of vibrations of the actuator is performed by modeling the experimental actuator device by a monodimensional magnetostrictive cylindrical rod attached to an elastic spring, subjected to an axial magnetic field. The formulation of the problem is carried out using the rod model. The study is carried out taking into account mechanical and magnetic effects described by a linear model of strain-stress magnetoelastic relations, whose coefficients depend on the square of the magnetic field, elastic, magnetostrictive, and magnetoelastic characteristics of the elastomagnetic material of which the rod is made. The dynamic equation which describes the magnetoelastic wave propagation in the actuator is obtained by applying the Lagrangian formalism based on the least action principle. The wave propagation is governed by a spatio-temporal partial differential equation whose coefficients are a function of on elastic, magnetostrictive, and magnetic characteristics and implicitly depends on time. The resolution of the dynamic equation is made by adopting two numerical approaches developed by combining the mesh-free collocation methods, the Moving Least Squares (MLS), and the Radial Point Interpolation Method (RPIM) with the Newmark implicit scheme temporal integration. By performing the spatial discretization of the displacement, we obtain a system of linear second-order ordinary differential equations (ODEs), then transform it into a system of first-order ordinary differential equations after integrating Newmark’s implicit time scheme. A comparison of results computed by the proposed numerical approaches RPIM and MLS with experimental data available in the literature is presented. The stability and the solutions qualities of two meshless methods, RPIM and MLS, are also studied. The influence of magnetical and mechanical parameters as well as the coupling coefficients on the performance of the magnetostrictive actuator is also made.

Currently, the geotextile industry is dominated by petroleum-based products, and the market share of bio-based geotextiles is still very low. With climatic and more generally environmental issues, combined with the scarcity of petroleum resources, the use of bio-based products appears to be an avenue of choice to explore. Through this study, we intend to raise the environmental benefits of a natural geotextile woven from fibers extracted from the leaves of the dwarf palm plant, an abundant renewable resource in Morocco and Mediterranean basin. We used the life cycle assessment analysis from cradle to factory gate following the requirements of ISO 14040 and ISO 14044 standards. Our main objective is to provide an environmental profile for this natural geotextile to encourage its use in soil protection and to stimulate therefore the local economy. The LCA analysis results showed that the transportation phase is the main contributor to almost every environmental impact category. We also noticed that no environmental impact was identified for the raw material supply phase which is characterized by a traditional harvest of raw palm leaves from the palm plant that grows spontaneously in eco-friendly environment. A comparison with two examples of petroleum-based geotextiles available in the market shows that palm-fiber-based geotextile presented the lower impacts in all the categories, except for eutrophication and ozone layer depletion potentials, its carbon footprint is relatively low and can save an average of 0.84 Kg CO2 eq. per surface unit (1 m2), nevertheless, its water consumption exceeds that recorded for synthetic geotextiles. Finally, palm-fiber geotextile can compete with the synthetic ones used in soil erosion, it is designed from renewable resource, naturally biodegradable, requires little energy for its production, and contribute to the reduction of greenhouse gas emissions.

$BaWO_{4}$, $Ce_{2/3}\square_{1/3}WO_{4}$ and $La_{2/3}\square_{1/3}WO_{4}$ polycrystalline ceramics were synthesized by conventional solid-state reaction route. The effect of cation-deficiency on the crystallographic structure, microstructure and thermal properties of these scheelite-type compounds were investigated. X-ray diffraction was used to identify the single-phase scheelite structure of the studied ceramics. Scanning Electron Microscopy technique has revealed a homogenous and dense microstructure with a few micro-cracks. The thermal conductivity of $BaWO_{4}$ scheelite decreases from $1.3\pm0.2$ to $1.0\pm0.1 W m^{-1} K^{-1}$ in the range 373 K - 673 K. The cation-deficient scheelites $Ce_{2/3}\square_{1/3}WO_{4}$ and $La_{2/3}\square_{1/3}WO_{4}$ ceramics display an ultra-low thermal conductivity of $0.3\pm0.04 W m^{-1} K^{-1}$ and $0.2\pm0.03 W m^{-1} K^{-1}$ at 673 K, respectively. These materials exhibit among the lowest known values of thermal conductivity in crystalline oxides, in this temperature range. Therefore, they appear as very attractive for thermal barrier coating and thermoelectric applications., 18 pages, 4 figures

Morocco lives to the rhythm of social transformation and spatial depth, produced several new determinants of pathogenesis and epidemiological factors and multi-dimensional and mixed by dirt fields. If these factors relate to what is natural and economic, social and demographic and environmental, the results of these transformations are to deepen regional variations to health Moroccans and inequality before the death and disease. It is certain that health, which is a human development indicator affecting the quality of human life in the middle of the Moroccan environmental, represent a vital aspect of most aspects of social vulnerability expression of the reality of the situation. In this regard, this paper presents a study of the geographical variations of the regional health status in Morocco, and dealing with the diagnosis and analysis of a number of indicators, including the index display health treatments and measuring health status through three indicators are: "Morbidity" or disease, mortality, and disability. The study also envisages, highlighting the role of geo-social, cognitive notable as one of the fields in the humanities, in addressing the issue of human health, which has been standing close to a monopoly on medical science and epidemiology. From the results of the study to monitor the regional disparities of diseases and patients and structures medical and paramedical existence of views and cities known levels of concentration strong, Such as Casablanca, Rabat, and the other suffering from an acute shortage and shortfall in all fields of health services.

This study examines the three-dimensional heat transfer and flow characteristics of nanofluids in a parabolic trough solar collector under turbulent flow conditions, whereas a non-uniform focused heat flux was applied to the absorption pipe. CuO/water, Al2O3/water, TiO2/water, and SiO2/water are studied numerically. The dynamic and thermal fields are determined by the Reynolds number varying between 50000 ≤ Re ≤ 250000, while the volume concentration of nanofluids is the following: 3% CuO, 6% Al2O3, 4.82% SiO2 and 3.15% TiO2, the nanoparticle size of 30 nm by means of Finite Element Method (FEM). Effects of various parameters such as volume fraction of nanoparticles (φ), various Reynolds numbers and type of nanoparticle on thermo-hydraulic performance of the parabolic solar collector are studied. The average Nusselt number, heat transfer coefficient, average friction factor, pressure drop, temperature and velocity distribution are illustrated using four different types of nanofluids and four different volume fractions of nanoparticles with various Reynolds numbers. According to the final results, both TiO2 and CuO nanofluids have better performance in terms of thermal and hydraulic efficiency and evaluation economic performance compared with other nanofluids studied.

In this work, we treated wastewater from the detergent manufacturing industry on natural carriers and by-products from a coal-fired thermal power plant. The filtration was carried out by infiltration- percolation using a vertical cylindrical column manufactured in our laboratory. The main parameters analyzed before and after treatment are: suspended matter (SM), chemical oxygen demand (COD), biochemical oxygen demand (BOD5) and pH. This treatment system achieved a reduction of 89% COD, 73% BOD5, 54% SS and (66-99%) heavy metals. The COD/BOD5 rejection ratio before treatment, which was greater than 4.24, has become less than 1.73. Thus, impedance measurements of the wastewater before and after treatment were carried out. The results of the electrical parameters deduced from the impedance spectra show a good correlation with the parameters obtained by the classical methods.