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Abstract The work is focusing on air pollution impacts on historical limestone buildings located in urban areas in Morocco. Black crusts sampled on the façades of two ancient limestone monuments, dating back to the 12th and 20th centuries edified in the cities of Salé and Casablanca, have been analyzed by means of ATR-FTIR and synchronous fluorescence spectroscopies. Infrared analyses revealed degradation products, mainly gypsum due to calcite sulphation under wetness and SO 2 rich oil fired soot, and oxalates due to ancient biological weathering. Synchronous fluorescence permitted the identification of the most hazardous PAHs along with other non-identified fluorescent organics; this technique appeared efficient and suitable for the analysis of fluorescent pollutants entrapped in black crusts. Such results keeping track of air pollution causing disfigurement of architectural heritage must alarm both cultural heritage and environmental decision makers. Highlights • Air pollution impact on historical limestone buildings, in Moroccan urban areas, has been focused. • Black crusts deposits were explored by means of synchronous fluorescence and ATR-FTIR spectroscopies. • Hazardous PAHs and calcite degradation products were detected in black crusts from exposed façades. • A constant wavelength synchronous fluorescence spectra database of fifteen hazardous PAHs was elaborated. [ABSTRACT FROM AUTHOR]

Two Moroccan antic wool carpets “zarbia(s)” registered at the Oudayas museum of Rabat, belonging to two main dyeing and weaving schools, Taznakht and Chiadma, have been expertized by means of UV-vis diffuse reflectance, 3D-fluorescence and Raman spectroscopies. All original dyeing materials were identified. Madder roots were used for red shades, Reseda luteola or Rhamuns carthacus plants for bright yellows, Lawsonia inermis for orange-yellows, Indigofera tinctoria for blues and the synthetic Malachite green for a particular bright green shade. Combined-dyes based recipes were also revealed by 3D-fluorescence; some green shades were identified as Indigo and flavonoids combined-dyes recipes and some reddish yellow shades identified as Madder and flavonoids combined-dyes ones. The study permitted also a spectrometric characterization of the most popular dyes used in ancient wool dyeing handcraft in Morocco; 3D-fluorescence seems a reliable tool to fingerprint emitting dyes on their wool substrate. Efficiencies of the optical spectrometric techniques adopted were compared. [ABSTRACT FROM AUTHOR]

The catalytic dehydrogenation of isopropanol is an important area of the catalytic process to produce fine chemicals and has important applications in heat pumps, fuel cells, and acetone production. Thereby, the catalytic liquid-phase dehydrogenation of isopropanol has gained attention over the last decades and has used a large variety of homogeneous and heterogeneous catalysts. In this paper, nickel nitride (Ni3N) nanoparticles, having a cubic structure, were successfully synthesized in simple and efficient methods either from nickel oxide or from nickel complex. The morphological and structural analyses of the obtained nanoparticles were performed by using powder X-ray diffraction (XRD) and scanning electron microscopy with energy-dispersive X-ray spectroscopy (SEM/EDX). At room temperature and under atmospheric pressure, the dehydrogenation test of isopropanol, using nickel nitride as a catalyst, revealed very high activity and better Hydrogen production. • New Nickel nitride was used for the dehydrogenation of isopropanol. • Preparation methods are simple, effective, and less expensive. • Morphological and structural analyses of the new materials have been performed. • Catalytic dehydrogenation test of isopropanol has shown very good results. [ABSTRACT FROM AUTHOR]