There is a good literature mutual aid network, Xiaomi Resource Network (of course, it is different from medical and chemical literature and can help you, super fast, don't get me wrong).
Completely free once and for all, free for life, come on.
Specific methods of obtaining documents,
1 Apply for membership first.
Address: Xiaomi Resource Network (I know I can't see the URL in Baidu search)
Just post the documents you want to the document retrieval mutual assistance area for help! It's that simple. There are many experts here, mainly college students, who can download any document you want in 5 minutes. Faster than you can find yourself. ..
Available literature databases include
Domestic: cnki Weibo Wanfang cnki (China Wang Zhi China Periodical Network), Superstar Books Reading Exhibition Books.
Abroad: major database documents such as ScienceDirect, ProQuest, Science, ACS, RSC, Ebsco, Springer, Blackwell, ieee, nature, etc.
In addition, Xiaomi Resource Network also provides long-term free account passwords such as VIP, Superstar and Wanfang cnki (China Knowledge Network China Journal Network) for everyone to use.