title: The nitrogen fix.
mesh_terms: D000641:Ammonia / Q000138:chemical synthesis*; D002384:Catalysis; D005308:Fertilizers / Q000266:history / Q000600:supply & distribution; D049672:History, 19th Century; D049673:History, 20th Century; D049674:History, 21st Century; D006859:Hydrogen / Q000737:chemistry; D007501:Iron / Q000737:chemistry*; D009584:Nitrogen / Q000737:chemistry; D009586:Nitrogen Fixation; D009613:Nobel Prize
chemical_list: D005308:Fertilizers; D000641:Ammonia; D006859:Hydrogen; D007501:Iron; D009584:Nitrogen