Ultrasonic detector

{
  "id": "MLC-T-CHM-013678",
  "term": "Ultrasonic detector",
  "field": "Chemistry",
  "definition": "A device that measures the concentration of a substance by detecting changes in the speed of sound through a medium. In gas chromatography, it measures the time it takes for an ultrasonic sound wave to travel across the column effluent. The presence of analyte molecules alters the gas density and thus the sound velocity relative to the pure carrier gas.",
  "subject": "Chemistry and the Environment",
  "see_also": [
    "thermal conductivity"
  ],
  "references": [
    "PAC, 1990, 62, 2167. 'Glossary of atmospheric chemistry terms (Recommendations 1990)' on page 2192 (https://doi.org/10.1351/pac199062112167)"
  ],
  "url": "https://mlchart.com/terminology/chemistry/ultrasonic-detector/"
}