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The k0-method of neutron activation analysis (k0-NAA) was used in order to determine the concentration of major and trace elements in sediment samples collected from different sites in the Gharb plain along the Sebou River (Morocco). Samples have been analyzed using neutrons of the Moroccan Triga Mark II research reactor. Two types of irradiation (short and long) have been carried out using the Pneumatic Tube System (PTS) and the Rotary Specimen Rack (RSR). Acquisition and Fitting of spectra have been carried out by Maestro software and k0-IAEA program respectively. Pollution indicators (enrichment factor (EF), geoaccumulation index (Igeo), contamination factor (CF) and pollution load index (PLI)) were calculated to assess the pollution status of the sediments. Results of pollution indices showed no contamination all around the catchment area except for the stations (MS1 and MS2) located downstream the Sebou river. Principal component analysis (PCA) was carried out with the Pearson coefficient in order to determine possible relationships between major and trace elements. The comparison with other subsequent studies on Sebou river gives an idea about the temporal evolution of heavy metal contamination at national scale.

Two series of Zelliges belonging to the Filalia and Bou-Inaniya Medersas (14th-century) in Meknes city have been studied in order to describe precisely the colour of the glazes and to identify the chromogen agents responsible for these colours. The glaze colours are physically studied by the determination of their chromatic coordinates using chromametry method. These coordinates are represented in the conventional Yxy and L*a*b* spaces. Furthermore the chromogen ions, responsible for the different colour shades, are identified by optical absorption spectrometry (OAS) and by electron paramagnetic resonance (EPR) methods. These ions are the classical ones: copper (Cu$^{2+})$for the green, cobalt (Co$^{2+})$for the blue, iron (Fe$^{3+})$for the honey colour and iron (Fe$^{3+})$in association with manganese (Mn$^{3+})$for the black.

Ground and excited state self associations are observed in solution at room temperature in the case of the 9-oxa-2,3,4‘-methoxybenzobicyclo[4.3.0]non-1(6)-ene-7,8-dione molecule. Depending on the solute concentration, the ground state associated forms are attributed to a dimer involving interaction between only two solute molecules, or to an aggregate of higher order. The theoretical simulation, using the analytical atom−atom pair potential described below, predicts several energy minima of the dimer. The two most stable dimer's structures are those involving a face-to-face slipped structure with head-to-tail orientation. An excimer emission is also observed subsequently to the excitation by either the absorption monomer bands or by the absorption band of the van der Waals dimer. The two adjacent molecules forming the excimer species are readily in approximately parallel planes.