Di was trained as a radio astronomer and is now an expert in long wavelength spectroscopic observations, both from ground and space. He has a BS in nuclear physics from Peking University and a PhD in astrophysics from Cornell University. He has led and participated in more than 10 space or airborne observational programs including those on SWAS, Spitzer, Herschel, and SOFIA. He focuses on the evolution of interstellar medium, in particular, the transition from atoms to molecules. His related publications have been cited by an article on Annual Review of Astronomy as having developed a robust method for measuring cloud forming time scale and also by Nature as a science highlight. At SSI, Di will bring his roots in radio astronomy together with his experience in space missions. In particular, he will carry out various Herschel and SOFIA programs with emphasis on high resolution spectroscopy. In his spare time, Di enjoys tennis and Go chess.