1) “Thermal solar collector with tapered tubes for application with traditional heat transfer fluids and inseminated with particles and nanofluids” - WO 2011138752 (A1)
Inventors: Gianpiero Colangelo, Ernani Favale, Arturo de Risi, Domenico Laforgia. (PCT/IB2011/051988 - 05/05/2011 International Bureau of the World
Intellectual Property Organization)

2) “Nanofluids for thermodynamic solar system”
Inventors: Domenico Laforgia, Gianpiero Colangelo, Milanese Marco, Arturo de Risi. (11425185185.3 – 2301 – 08/11/2011 European Patent Office)