The most dangerous and deadly things may not be what we see, but what we don’t. In the air there are potentially undetected hazardous chemicals. Jeffrey Hopwood, an electrical engineer at Plasma Science and Engineering at Northeastern University in Boston, invented a portable microplasma device to detect deadly toxins in the air. It use a spectrometerto measure the unique set of colors or wavelengths emitted by dangerous chemicals.Depending on the colour researchers can determine the type and amount of contamination.For example,sulphurdiooxide is released from burning coal and causes acid rain. The device would give ff a blue-green colour,indicating sulphur.
The microplasma device converts samples taken from the air into very small plasmas and then measures the unique set of light colours(wavelenghts) that are subsequently emitted by the electrically charged atoms and molecules. A cell -phone chip supplies the radiowave energy need to create the microplasma.Instead of beaming those radio waves to the outside world,that energy is concentrated inside the unit,in a microscopic gap about one-halfthe width of a human hair within a thin ring of gold. All that energy in that small causes the collected gases in the gap to become what scientists call ‘ionised’ the electrons are stripped from the gas atoms. The device watches the light emission from the plasma to determine if there are any contaminants in the air.It can do this because everychemical element has a distinct qualities in the form of what kind of light it will emit under those circumstances.