Protoplanetary disk

Four scenarios in a gas-grain dark cloud model show that this reaction, the destruction of benzene with carbon, dominates benzene loss, and this best reproduces observed cyclopentadiene and benzene derivatives when the hydrogen loss channels stay minor.

Number three, Ammonium Salt Formation and Abundance in Protoplanetary Disks by Raoud et al.

on the Archive.

Nitrogen appears strongly depleted in comets, and one explanation is that it hides in less volatile ammonium salts, as Rosetta results in 67P and some recent ice detections in disks seem to suggest.