... , LPG, Mixed Gas, High Purity Gas (Ar,He,O2,N2,CO2)3. Food Additives & Pesticide Residue (organophosphorus, organochlorine,amino acid methyl ... , acetaldehyde)5. Dissolved Gas (hydrogen, methane, ethane, ethylene, acetylene, carbon monoxide, carbon dioxide)6. Petrochemical Testing and Fine Chemicals (crude oil, gasoline, essence ...