"Ambient PM2. 5, O3, and NO2 exposures and associations with mortality over 16 years of follow-up in the Canadian Census Health and Environment Cohort (CanCHEC)".

Apr 16, 2025 · OpenAI o3 and o4-mini are the most intelligent models we have ever released, and they’re also often more efficient than their predecessors, OpenAI o1 and o3‑mini.

Jun 6, 2025 · Ozone (O3) is a highly reactive gas composed of three oxygen atoms. It is both a natural and a man-made product that occurs in the Earth's upper atmosphere (the …

Jun 9, 2025 · It may be hard to imagine that pollution could be invisible, but ozone is. The most widespread pollutant in the U.S. is also one of the most dangerous.

Jan 28, 2025 · Ozone (O₃) – Definition, Structure, Preparation, Uses, Benefits, Side Effects Ozone is a special kind of gas. This bond forms what scientists call a covalent compound, …

Dec 12, 2025 · ozone layer A view of the Earth's ozonosphere, or ozone layer, from space. This region of the upper atmosphere contains relatively high concentrations of ozone molecules …

Ozone (O3) is a gas that can form and react under the action of light and that is present in two layers of the atmosphere: the stratosphere and the troposphere.