Basically Nexus/STC is an attempt to recreate sci-hub but in a decentralized manner. Everything is mirrored on IPFS which in my opinion is not that great but it gets the job done. Sci-hub has been frozen since 2021 so new papers are not available. As time progresses, sci-hub becomes less and less useful.

Scientific articles are crowd sourced instead of scraped. If the article isn't on there it can be requested. They also mirror libgen databases.

Also it's named Standard Template Construct as a Warhammer reference.

Here is a link on how to use it.