Å®ÉúСÊÓƵ

Air travellers may soon be asked to walk through a drug and
explosive-sniffing tunnel before boarding their plane. Ion Track Instruments of
Massachusetts say they can pick up telltale signs of contraband just from air
flowing over someone’s body (EP 992 782). The company takes Teflon-coated woven
glass fibre and rubs it with an abrasive, which makes tiny cuts in the Teflon
and breaks some of the fibres free. The glass fibre then acts as a filter at the
end of a tunnel, trapping traces of cocaine or plastics explosive in the
fractured weave. When you heat the fabric to 200 °C any traces of drugs will
evaporate and be picked up by a spectrometer.