Radiation protection, environmental radioactivity, radioecology, and nuclear safety. Development of new methods/techniques/technology for the measurements and mitigation of radioactivity in 

the environment and workplaces. Accelerator mass spectrometry (AMS), gamma spectrometry, liquid scintillation spectrometry, alpha spectrometry and neutron activation analyses. Application of natural and anthropogenic

radionuclides for studying environment, such as soil erosion, sedimentation rate and transportation measurements, atmospheric mixing studies, submarine water discharge, etc.