It's definitely not 1:1 and for a while, every degree you gain results in less particles and barely any NOx. But to get rid of the remaining particles, you need to reach higher temperatures and then NOx emissions is going to increase.
So there is a “sweet spot”, which is what's targeted by car engine manufacturers since air pollution norms have been enacted, but we can agree that the result is not “clean”, it's just “the least bad you can do”.
So there is a “sweet spot”, which is what's targeted by car engine manufacturers since air pollution norms have been enacted, but we can agree that the result is not “clean”, it's just “the least bad you can do”.