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Waste rock materials are becoming widely used in road pavement and building constructions in many countries. In this work, experimental laboratory tests were carried out on the waste rock produced from the extraction of the phosphate in the Kef-Essenoun mine, to study the performance of road pavement foundations built with these types of material. Two types of waste, namely phosphatic limestone (type 1) and limestone (type 2), were initially tested to determine the most suitable one to be used in pavement structures. The characterization tests showed that the presence of carbonate-fluorapatite and carbonate-fluorapatite, and calcite, dolomite, and quartz are predominant in phosphatic limestone and limestone, respectively. The Los Angeles Abrasion (LA) and Micro-Deval (MD) values range from 59.9% to 90.4% and 42.05% to 86.31% for phosphatic limestone and from 43.64% to 95.88% and 38.25% to 75% for limestone. The CBR values of type 1 and type 2 waste were found to be 10.5% and 18.7% respectively. The results show that these materials, classified as B42ts and B42s respectively, could be used cautiously in capping layers and pavement backfilling materials. Furthermore, they must be treated with a hydraulic binder such as cement in order to improve their physical and mechanical properties.

Environmental problems on a global scale have become more prominent with the population growth. For the removal of organic contaminants, the solar energy and environmentally friendly photocatalysis are needed to substitute the fossil fuels. In this contribution, we report the synthesis, characterization and photocatalytic capability of CuAl2O4 nanoparticles. The spinel was elaborated by nitrate route and characterized physically and electrochemically for their correlations and application in photocatalysis through the degradation of Basic Red 46 (BR 46), a hazardous dye under visible illumination. The effects of several operational factors like the pH, catalyst dose and initial dye BR 46 concentration were optimized. The results revealed that the photocatalytic performance reached 93% at pH 10, 1 g/L of catalyst dose at a concentration of 10 mg/L of BR 46 within 120 min of irradiation. The quasi-total mineralization was confirmed by the total organic carbon (TOC) and dissolved organic carbon (DOC). Additionally, the prepared photocatalyst possesses a good cyclability with no significant change after five successive photocatalytic cycles. Furthermore, the radical scavenger tests revealed that the specie O2·− and the holes h+ have the significant effects on the removal of BR 46. Based on the latest results, a photocatalytic mechanism was proposed.

The spinel MgFe2O4 synthesized by sol gel method, was characterized by physical and electrochemical methods. The thermal analysis (TG) gives an optimal synthesis temperature of 650 °C where the X-ray diffraction pattern exhibits a single phase crystallizing in a cubic symmetry (Space Group: Fd $$\stackrel{-}{3}$$ m) with spherical crystallites (~ 0.45 µm). The morphology observed through the SEM image shows elliptical and spherical grains of ~ 0.8 µm. The spinel possesses a direct optical transition (2.16 eV) due to electrons transfer Fe3+: d−d transition, coming from the crystal field splitting in agreement with the red color. The low electrons mobility is assigned to a narrow conduction band of Fe3+: 3d parentage with activation energy (0.14 eV) in conformity with a conduction mechanism by small polaron hopping. The semi-logarithmic plot confirms the chemical stability of oxide. Unlike other spinels, the capacitance plot exhibits n type conduction confirmed by chrono-amperometry with a flat band potential (Efb) of 0.27 V. The electrochemical impedance spectroscopy displays a semi-circle attributed to the bulk behavior. As application, the photodegradation of methylene blue (10 mg L− 1) was successfully on the spinel suspension; 87% are eliminated after 2 h of exposure to sunlight irradiation.

This chapter aims to address the marketing information system MIS and its role in the face of marketing crises, especially in light of the ongoing changes and what needs him to current information about the surrounding environment. The study concluded that the marketing information system MIS plays an active role in the management of the marketing crisis by properly exploiting the huge amount provided by big data of classified data, and stored according to a database that helps to speed the flow to allow for the response of these crises and predict.

In this paper, an experimental facility is implemented with the aim of improving the performance of internal combustion engines working at low ambient temperatures. Pollutant emissions and fuel consumption are one of the major issues that automotive engineers have to face. Cold engine start and warming up analysis have become important topics for researches. In this work, an exhaust heat recovery system for a diesel engine has been proposed as a solution to cold operation negative effects. The energy obtained from the exhaust gases was used to increase the intake air temperature. The experiments were carried out in transient load conditions at three different levels of ambient temperature (up to -7ºC). Exhaust heat recovery was combined with different strategies of exhaust gas recirculation. Intake air heating results with the heat recovery system show a reduction of 65% in unburned hydrocarbons, 40% in carbon monoxide and 10% in fuel use compared to standard air-air intercooler., This research has been partially financed by the Ministerio de Economia y Competitividad of Spain, through project IPT-370000-2010-022 'Investigacion y desarrollo de tecnologias de EGR adaptadas a las nuevas arquitecturas y requerimientos de refrigeracion en motores diesel sobrealimentados para automocion (HIREFIRE)'. The authors gratefully appreciate this support. Authors want to acknowledge the "Apoyo para la investigacion y Desarrollo (PAID)" grant for doctoral studies (FPI S2 2015 1062).

Polyethersulfone (PES) was successfully sulfonated by sulfuric acid and used for membrane synthesis. Silica nanoparticles were functionalized by amine and thiol groups and then introduced in a sulfonated polyethersulfone membrane (SPES) matrix. The effect of silica and functionalized silica particles on ion exchange of lead ion (Pb2+) and cadmium ion (Cd2+) was studied. X-ray diffraction (XRD), attenuated total reflectance-Fourier transform infrared spectroscopy (ATR-FTIR) and scanning electron microscopy-Energy dispersive X-ray spectroscopy (SEM-EDX) analysis were used to confirm the successful functionalization of silica particles and the effective incorporation of silica and the functionalized silica particles in the membranes matrix. The dialysis process during 8 h,using the SPES-SiO2-(CH2)3-NH2 membrane, leads to a significant elimination rate of Pb2+and Cd2+ ions estimated at 43.2% and 31.6%, respectively. whereas a selective separation of Pb2+ from feed (Pb2+/Cd2+) solution was observed at 2 h of dialysis. On the other hand, the SPES-SiO2-(CH2)3-SH membrane adsorbs more Cd2+ than Pb2+ ions, which represents another outcome for Pb2+/ Cd2+ separation.

This investigation is consecrated to the influence of the shape and curvature radius of the made of steel electrodes on the maximal values of the applied electric field, enabling thus to establish a relation between the minimum approach distance and the shape of the tools used in the pertinent high voltage working area. The obtained results are of a great importance for accurately dimensioning the safety Minimum Approach Distances (MAD) for future live works that can be performed with non normalized tools.

The purpose of this article is to develop an integral derived from the double transfer and excitation theory. The reduced form of this integral, so obtained, can serve in the computation of the transition amplitude which is from numerical point of view difficult to implement. This amplitude is of great interest in the resonant and non resonant transfer and excitation (RTE and NTE) processes.

This paper deals with the generalized integral quadratic method (called GIQ) to the system of Volterra integral equations. The linear treatment of the system as well as the nonlinear treatment have been developed. The numerical examples are also presented.

This paper presents a numerical survey on electric field distribution in electrode arrangements commonly met while executing a live working on overhead lines. This numerical investigation is achieved using a software package based on charge simulating method. Particularly, the influence of the curvature of the bodies under stress on the maximal value of the electric field and the predominance between the axial and the radial components of the electric field are shown. This knowledge is of a great importance for accurately dimensioning the safety minimum approach distances (MAD) for future works to be performed with nonnormalised tools. First, a rod-plane-wall configuration is addressed and satisfactory results are obtained. This allows bringing up into general use of charge simulating program (CSP) to determine the safe MAD for complex configurations. A method that consists in use of the numerical techniques to adapt the empirical methods for the evaluation of the MAD, when tools of nonconventional dimensions are used, is then developed.