Visitors participate in an experiment at a lab of the Institute of Physics in the Chinese Academy of Sciences (CAS) in Beijing, capital of China, May 19, 2018. The 14th CAS "Public Science Day" kicked off on Saturday. (Xinhua/Jin Liwang)

Visitors watch video on superconductivity at a lab of the Institute of Physics in the Chinese Academy of Sciences (CAS) in Beijing, capital of China, May 19, 2018. The 14th CAS "Public Science Day" kicked off on Saturday. (Xinhua/Jin Liwang)

Visitors view a lid painted with equation at the Institute of Physics in the Chinese Academy of Sciences (CAS) in Beijing, capital of China, May 19, 2018. The 14th CAS "Public Science Day" kicked off on Saturday. (Xinhua/Jin Liwang)

Visitors watch a robot dog at the Institute of Computing Technology in the Chinese Academy of Sciences (CAS) in Beijing, capital of China, May 19, 2018. The 14th CAS "Public Science Day" kicked off on Saturday. (Xinhua/Jin Liwang)

A volunteer introduces a calculator to visitors at the Institute of Computing Technology in the Chinese Academy of Sciences (CAS) in Beijing, capital of China, May 19, 2018. The 14th CAS "Public Science Day" kicked off on Saturday. (Xinhua/Jin Liwang)