1. Senior scientist, Institute of Chemical Analysis, Northeastern University, 341 Mugar Bldg. 360 Huntington Ave. Boston, MA 02115, US.
2. Visiting Chinese scholar, Analytical Chemistry Institute, Chinese Academy of Sciences, Beijing, CN.
3. Graduate student, Forensic Chemistry, Department of Criminal Justice, Northeastern University, Boston, MA, US.
4. Analytical research chemist, Pfizer Central Research, Pfizer & Co., Inc., Groton, CT, US.
5. Associate director, Analytical Research Department, Pfizer Central Research, Pfizer & Co., Inc., Groton, CT, US.