Potentially Exposed during Chemical and Biological Tests. Such series are useful for determining necessary solvents needed for chromatography of chemical compounds. These include mechanical, chemical, and biological methods. Physical, chemical and biological tests can be conducted. Mutagens may be of physical, chemical or biological origin. Petroleum classification according to chemical composition. Several barriers protect organisms from infection, including mechanical, chemical, and biological barriers. Component degradation of a substance occurs by chemical or physical processes, e.g. hydrolysis. It revealed some of the secret German efforts in chemical and biological warfare. Assaying is analysis of the chemical composition of metals. Plutonium is a synthetic element with complicated physical, chemical and metallurgical properties. It is a common industrial chemical. Some images contain indications of chemical composition. She has PhDs in petroleum exploration and chemical engineering. It involves a change of chemical composition.