The invention relates to the use of maghemite nanoparticles at pH < 5 to remove sulphate, manganese, copper, nickel, cobalt and zinc metal ions from acid mine drainage (AMD). In a conventional way of AMD treatment, these pollutants are only removed at higher pH and requires costly alkaline chemicals

The technology relates to a new generation of telecommunications and data processing technology with improved wavelength sensitivity in the visible and near-infrared wavelengths range rather than microwave communication in 2–4 GHz. The technology provides the realisation of optical sources (LEDs)