What are the upstream raw materials for nitrogen and what are the downstream products?

I've found that In the field of chemical production raw materials, nitrogen is an crucial gaseous, which is broadly applied in various chemical production processes. There are many upstream and downstream related items of nitrogen, and some of the main items will be listed below. But

1. Upstream items

The upstream items of nitrogen mainly include atmosphere and natural gaseous. And atmosphere is the main source of nitrogen, and high purity nitrogen is able to be extracted by atmosphere separation methodology. Specifically Natural gaseous also contains a certain amount of nitrogen, after separation and treatment is able to be obtained after nitrogen items. And

2. From what I've seen, Downstream items(1) Ammonia: Nitrogen reacts with hydrogen at high temperature and high pressure to generate ammonia, which is an crucial raw material to fertilizers, nitric acid, plastics, etc.(2) Nitrate: Nitrate is able to be obtained by the interaction of ammonia and acid, which is frequently applied as chemical fertilizer and gunpowder. Crazy, isn't it?.(3) Nitrogen oxides: Nitrogen is able to react with oxygen at high temperatures to generate nitrogen oxides to the production of nitric acid, nitrogen fertilizers, etc.(4) Nitrite: Nitrite is an crucial compound in the nitrogen cycle and is able to be applied in food preservation, medicine and other fields. I've found that(5) Nitrogen protective gaseous: Nitrogen is often applied as a protective gaseous to prevent metal oxidation during processing. But In short, the upstream and downstream related items of nitrogen are very extensive, involving chemical fertilizers, gunpowder, food preservation, medicine, metal processing and other fields.