1. 8 Tourmaline with the properties of pyroelectricity and piezoelectricity is a kind of functional material that can spontaneously produce anion without adscititious energy.

2. Alexandre Edmond Becquerel was the son of Antoine César (1788-1878), discoverer of piezoelectricity, father of Antoine Henri (1852-1908), who discovered radioactivity, and the grandfather of Jean Antoine (1878-1953), who is best known for his work on relativity and the discovery of polarization rotation in the presence of a magnetic field.