The National Science Library of the Chinese Academy of Sciences adopted an open access mandate this February.
Here's an excerpt from the library's home page that describes it:
NSLC functions as the key library nationally for collecting information resources and providing information services in natural sciences, inter-disciplinary fields, and high tech fields, for the researchers and students of CAS and for the researchers around the country. It also conducts services such as information analysis, digital library system development, scientific publication (with its 14 journals), and promotion of sciences. It also operates the Archives of CAS.
NSLC has a staff over 470, building areas more than 80,000m2 [square meters], and a collection about 11.5 million items
Read more about it at "Open Access Mandate in the National Science Library (NSL), Chinese Academy of Science (CAS)" and "Open Access Practice in National Science Library, Chinese Academy of Science."