Comparison Between the Influences of Phosphatidylcholine and Triton X-100 on the Protein Secondary Structures and Oxygen-evolving Activity of Photosystem ¢ò Study on the Binding State of Calcium in Photosystem ⅡOxygen-Evolution Complex 去锰PSⅡ颗粒放氧活性光活化的部分生化特性研究