Meet Arie Jan Haagen-Smit

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Arie Jan Haagen-Smit was a Dutch-American atmospheric chemist who made significant contributions to our understanding of air pollution and its impact on human health and the environment. 

He is considered a pioneer in the field of air chemistry and his work has had a lasting impact on air quality research and policy.

Here are three of Haagen-Smit's most notable contributions to science:

Haagen-Smit identified the role of photochemical reactions in the formation of smog. He discovered that sunlight can trigger chemical reactions between pollutants, leading to the formation of harmful air pollutants such as ozone and nitrogen oxides. 

This discovery was critical to our understanding of air pollution and led to the development of policies and technologies to reduce smog.

Haagen-Smit developed the first instrumentation for measuring the concentration of volatile organic compounds (VOCs) in the atmosphere. 

This technology allowed scientists to quantify the amount of VOCs emitted by different sources, such as cars and factories, and to study their impact on air quality.