Research area: experimental BiophysicsTeaching: PHY6780, Research Methods in Biomedical Physics; PHY5750, Biological Physics; PHY2130, General Physics

• Study the relaxational dynamics in protein and other biomolecules by Quasielastic Neutron Scattering (QENS). The experiments are performed on BASIS (backscattering spectrometer) at the Spallation Neutron Source (SNS), Oak Ridge National Laboratory (ORNL). This is the first experimental evidence of a logarithmic-like decay in the relaxational dynamics of protein molecules. • Study the diffusion processes in water on oxide surfaces by QENS experiments performed on BASIS and CNCS (Cold Neutron Chopper Spectrometer) at SNS, ORNL. This study first distinguished three different dynamic processes in the surface confined water. • Study the dynamics of protein molecules in LiCl solutions by QENS experiments on BASIS, SNS. This is the first study of protein dynamics in water based solution below dynamic transition temperature.

• Studied the low-temperature high-pressure dynamic behavior of bio-molecules and their hydration water. The experiments were performed at the NIST Center for Neutron Research (NCNR). This study discovered a counter- intuitive phenomenon in the temperature and pressure dependence of the dynamic behavior of protein and its hydration water.• Studied the dynamics of water confined in nanoporous materials such as double-wall carbon nanotube (DWNT), mesoporous carbon CMK-1 and porous silica material MCM-41-S. These studies provide a possible way of quantitatively determining the water interaction with different surfaces and geometries.• Studied the phonon behavior in protein molecules by Inelastic X-ray Scattering (IXS). The experiments were performed at Advanced Photon Source (APS), Argonne National Laboratory (ANL). This study discovered a phonon-like low energy excitation in protein molecules.

• Designed the electron beam transportation of Peking University Free Electron Laser (PKU-FEL). Performed simulation of the electromagnetic fields in the beam transport system of PKU-FEL.• Studied the CdS buffer layer for CuInSe2 (CIS) solar cell. Spectrum analysis on CdS thin films grown by chemical bath deposition.