化工工序合并
chemical industrial stages combination
焦化工业
coking and chemical industry
coking industry
北京石油化工工程公司环保所
Beijing Petrochemical Engineering Company EPI
大庆石油化工工程公司
daqing petrochemical engineering co
高分子化工工艺
high polymerized chemical techmological chain
广东工业大学轻工化工学院
Faculty of Light Industry and Chemical Engineering
Guangdong University of Technology
化工工人
Chemical plant workers
trace element
Employees of chemical factory
Chemical industry workers
化工化纤工艺管道
chemical industry and chemical fiber pipeline