The Chinese phrase Four Great Ancient Capitals of China (中国四大古都 pinyin zhong1 guo2 si4 da4 gu3 du1) refers to Nanjing, Beijing, Xi'an, and Luoyang.
... photophosphorylation, is a two-stage process involving two different chlorophyll photosystems. First, a photon is absorbed by the chlorophyll core of photosystem ...