Solvent Solvent A solvent (from the Latin "solvō", "loosen, untie, solve") is a substance that dissolves a solute (a chemically distinct liquid, solid or gas), resulting in a solution. A solvent is usually a liquid but can also be a solid, a gas, or a supercritical fluid. The quantity of solute that can dissolve in a specific volume of solvent varies with temperature. Common uses for organic solvents are in dry cleaning (e.g. tetrachloroethylene), as paint thinners (e.g. toluene, turpentine), as nail polish removers and glue solvents (acetone, methyl acetate, ethyl acetate), in spot removers (e.g. hexane, petrol ether), in detergents
Science of smells smells left by a criminal on a crime scene can be stocked in glassy jars for identification for purposes. The dog's olfaction, as criminalistics technology, developed thanks to works of a Hungarian doctor in 1970s in countries of Eastern Europe during Cold War, notably to identify dissidents. Science of smells The odorology or science of smells is a technology used mainly in criminology for judicial identification. The technology is based on the analysis of smells by dogs notably to merge the criminals or to identify the smell of objects (explosives, drugs). Olfaction of dogs is used for a long time