Having worked in Chinese academia, I can tell you that especially at the lower-level universities or institutes where the authors are pressured to produce papers, a common approach is to do your own research following exactly a published English-language paper (so, the data is yours but the experimental design / research questions are not) but the paper is cut-paste with your numbers substituted for the originals. The rationale is, it’s valid science (i.e., the experiments and data are correct) so who cares if we follow a template? The original must be good…. but this is a deeper issue in current Chinese culture in general, called by the brilliant author Yu Hua’s ‘Chinese in Ten Words’ “copycat” culture (山寨) — an insatiable desire to copy an original because it’s presumed to be excellent. Think Elvis impersonators.There are so many things about Chinese academic science that I do not understand. If I had any money, I would commission an article that would explain the overall funding structure of Chinese academic chemistry, the various institutions that are relevant (SIOC, I'm looking at you) and the various influential players. Surely the collaboration between the ACS and the Chinese Chemical Society would result in better understanding, yes? How does China's internal politics play into this? What kind of tenure pressures are there? What sort of financial pressures or cultural explanations are there?
None of those factors excuse plagiarism (whether of words or experimental design), of course -- but it would go a long way into explaining why things like this happen.