Finding new ways to get the measure of pollution

One of the world's leading authorities in mass spectrometry is manufacturing equipment to assess dangerous emissions. Guo Ying, Quan Xiaoshu and Zhou Qiang report for Xinhua.

Zhou Zhen and his team are busy "observing the invisible" in a lab. When an air sample passes through their mass spectrometer, the instrument's screen displays an analysis of its PM 2.5 content, the fine particulate matter found in polluted air.

Zhou has focused on the research and use of mass spectrometers for more than 20 years.