hello, i can help you as i am working as a research assistant , first SEM used in gunshot residue analysis , trace comparison and other applications i will explain it in research . second HPLC-MS ranging in uses from toxicology to environmental analysis , third x-ray used in determining the cutting agents used in illegal drugs . i will provide the search with examples from case studies , i wait your message to discuss about all points in search , thank you for your time .